[Tools] (trace_replay): let a caller that installed the APK itself skip the harness install - ColorOS confirms every adb install with a dialog whose tap drops adb mid-stream, so the install has to settle outside a run

.github/workflows/test.yml

@@ -601,7 +601,26 @@ jobs:
       # only in the pull `integration` job, where a MOBILEGL_PIPE_PUSH value steers nothing
       # (Config.h declares the field inside the push guard) and both arms are the same legacy path.
       # A lane that cannot go red where it is installed is not a gate (ROADMAP.md:7).
-      - name: The handle-ABA, CSO and P3a subsystem controls (G8, G10, G12)
+      # P4a ADDS THREE ALTERNATIVES, and each one is here because this is the only CI job that
+      # unpacks a push build:
+      #   * `ObjectSubsystem` reaches the three DirectGLES.ObjectSubsystemControl. entries - the
+      #     0x1fff-vs-0x1ff A/B and the 0x9ff dependency refusal (G12). `ResourceSubsystem` does
+      #     NOT match it: the two families are named apart on purpose, because they are different
+      #     phases' switches and a filter that merged them would hide one behind the other.
+      #   * `TextureParamsWithoutASamplerView` reaches G9's four cases, the scenario ROADMAP.md:20
+      #     names by hand. It runs in the ambient lanes, which the label already selects - but this
+      #     step is where those cases run against a PUSH library, and G9's whole claim is about the
+      #     push path. All four cases are green on the contract commit - including the one D-E3
+      #     expected to be red, for the reason the scenario's header records - so this row is green
+      #     from the day it lands and goes red only if a reachability path stops syncing texture
+      #     parameters at all, which is the coupling ARCHITECTURE.md:100 exists to remove.
+      #   * `TextureUploadShape` is RECORDED, not gated (D-D4): it asserts that the two upload-shape
+      #     counters could be read and that they agree, and prints the shape for MEASUREMENTS.md. It
+      #     is in the filter so that the number is actually collected on every run - an unmeasured
+      #     shape is not a recorded one - and because its own assertions can go red.
+      # As with the four before them, each alternative is the SHORTEST string that selects only what
+      # it means to.
+      - name: The handle-ABA, CSO, subsystem and texture-parameter controls (G8, G8b, G9, G10, G12)
         working-directory: build-verify
         env:
           MOBILEGL_ITEST_REQUIRE_GPU: "1"
@@ -612,7 +631,7 @@ jobs:
           ulimit -c unlimited
           sudo sysctl -w kernel.core_pattern='/tmp/core.%e.%p'
           ctest --output-on-failure -L integration-gpu \
-            -R 'HandleRecycle|CsoContentAddressing|ResourceSubsystem|MapPersistentRoundtrip' \
+            -R 'HandleRecycle|CsoContentAddressing|ResourceSubsystem|MapPersistentRoundtrip|ObjectSubsystem|TextureParamsWithoutASamplerView|TextureUploadShape' \
             --no-tests=error -j 4
 
       # The arming lanes' logs, and ONLY those. Each lane shares one MOBILEGL_LOG_FILE_PATH and the
@@ -771,7 +790,16 @@ jobs:
         run: sudo apt-get update && sudo apt-get install -y clang-20 libx11-dev
 
       - name: Include-closure assertions and negative control
-        run: python3 scripts/check_include_closure.py --mode both --compiler clang++-20 --self-test --require-all
+        # --expect-probes 4 (contract-v2.md 7.6): an exit code cannot tell four probes from none,
+        # so a --probe typo or a manifest edit that selected nothing would run zero probes and
+        # exit 0 - the second half of the finding that added the flag. The count is the length of
+        # scripts/check_include_closure.py's PROBES list and changing one means changing the other.
+        #
+        # --compiler stays clang++-20, which is what the step above installs (Debian's clang-20
+        # package ships /usr/bin/clang++-20). It is deliberately NOT the bare `clang++` the local
+        # campaign gate spells: that spelling exists because the WSL box has no clang++-20, and
+        # copying it here would trade a version-pinned compiler for whatever the runner has.
+        run: python3 scripts/check_include_closure.py --mode both --compiler clang++-20 --self-test --require-all --expect-probes 4
 
   benchmark:
     runs-on: ubuntu-latest
@@ -1557,12 +1585,18 @@ jobs:
     # Deliberately independent of build-linux: these are source-level gates, they take
     # seconds, and a broken build must not hide a drifted interface.
     env:
-      # P3a's base ref, for the G5 region gate below. It is 44c2b5cf and NOT the workflow's
-      # baseline_sha input: that input is the SYMBOL baseline (087685d1, P1's G1 reading) and it
-      # is empty on a push, whereas this gate asks "did the buffer pool, the deferred-release
-      # drain and the three rings move since the phase started". INTEGRATOR-DECISIONS ID-1 is
-      # where the ref comes from.
-      BASELINE: "44c2b5cf"
+      # THE CURRENT PHASE's base ref, for the two G5 region gates below. It is 37da3c3a - P4a's
+      # base ref, INTEGRATOR-DECISIONS ID-1 - and NOT the workflow's baseline_sha input: that input
+      # is the SYMBOL baseline (087685d1, P1's G1 reading) and it is empty on a push, whereas these
+      # gates ask "did the do-not-touch list move since the phase started".
+      #
+      # IT MOVED FROM P3a's 44c2b5cf TO P4a's 37da3c3a WITH THE PHASE, and that is a deliberate
+      # narrowing rather than a loss: P3a's eleven functions were compared against 44c2b5cf at P3a's
+      # own exit and were byte-identical there, so 37da3c3a carries the same bodies (measured: the
+      # eleven shas at 37da3c3a are the eleven shas at 44c2b5cf, and FlushPendingRangesFrom's is
+      # still the sha pinned in the script at 3e298c9a). What the two gates now both answer is "did
+      # anything on the list move during P4a", which is the question this phase can act on.
+      BASELINE: "37da3c3a"
 
     steps:
       - name: Checkout repo
@@ -1664,6 +1698,39 @@ jobs:
         if: ${{ github.ref == 'refs/heads/feat/disaggregated' || github.event_name == 'workflow_dispatch' }}
         run: bash scripts/p3a_untouched_regions.sh --self-test
 
+      # A GATE AS OF P4a (G5), and a SECOND script rather than an edit to the one above. P4a extends
+      # the same claim to the rest of ARCHITECTURE.md:318's do-not-touch list - the unpack PBO ring's
+      # staging repack and its two helpers, the attachment permutation, the D24S8 sampling-emulation
+      # core and the format-caveat handler - which is SEVENTEEN regions across THREE files
+      # (BRIEF-P4A.md D-N: P3a's eleven, which P4a must not touch either, plus P4a's six). The
+      # parent's SOURCE_PATH is a single file, so the extension needed a per-region source path and
+      # a region KIND (DepthStencilSamplingReadImpl is a namespace, not a function); everything else
+      # about the extraction is its parent's, verbatim.
+      #
+      # Both scripts run. The parent keeps answering its own question against its own eleven, so a
+      # regression in either half names itself, and neither gate can be silenced by editing the
+      # other's list.
+      #
+      # Same feat/disaggregated-or-dispatch guard as the P3a step, for the same reason: the question
+      # is "did these move since the phase started", and on dev - where unrelated buffer and texture
+      # fixes land on their own schedule - it would be a question nobody posed. It belongs with the
+      # TEMPORARY trigger lines at the top of this file and retires with them.
+      #
+      # --self-test is the half that keeps it honest and is not optional: a comparison that silently
+      # stopped comparing produces exactly the same green as seventeen untouched regions. It runs
+      # three positive controls (seventeen regions extracted, an untouched copy compared equal, an
+      # edit OUTSIDE them invisible in all three files) and FOUR negative ones - ClearBufferPool,
+      # FlushPendingRangesNow, RecomputeBackendColorSlots and StageBlocksIntoUnpackRing, each
+      # perturbed on its own and each required to be named BY NAME - and fails if any of them does
+      # not answer.
+      - name: The unpack ring, the attachment permutation, the D24S8 core and the format caveat did not move (G5)
+        if: ${{ github.ref == 'refs/heads/feat/disaggregated' || github.event_name == 'workflow_dispatch' }}
+        run: bash scripts/p4a_untouched_regions.sh "${BASELINE}" HEAD
+
+      - name: The P4a untouched-region gate can still fail (G5)
+        if: ${{ github.ref == 'refs/heads/feat/disaggregated' || github.event_name == 'workflow_dispatch' }}
+        run: bash scripts/p4a_untouched_regions.sh --self-test
+
       # Warning only for now: the disaggregation documents are still being written, and a
       # lint that fails a rewrite in progress teaches people to ignore it. It becomes
       # --strict when the documents settle.

MobileGL/MG_Backend/DirectGLES/Managers.h

@@ -20,6 +20,11 @@
 #if MOBILEGL_PIPE_PUSH
 // P3a: the vertex-input payload views the handle arm of the VAO twin consumes.
 #include <MG_Pipe/MGPipeTypes.h>
+// P4a: the RECORDS the five re-keyed twins read instead of the frontend object. The readers
+// below hand back pointers to them, and MGPipeResourceRecord::PendingUpload is a nested type,
+// so a forward declaration would not do. Push-only, like everything else P4a adds to this
+// header, so the pull build's include graph is unchanged (D-P).
+#include <MG_Pipe/PipeApply.h>
 #endif
 
 namespace MobileGL::MG_Backend::DirectGLES {
@@ -428,6 +433,52 @@ namespace MobileGL::MG_Backend::DirectGLES {
             return nullptr;
         }
 
+        // P4a (D-B1): resolve-or-create BY THE HANDLE THE CALL CARRIED. This is the shape P3a
+        // already runs for the buffer family through BackendBufferResourceTable, lifted onto
+        // the five registries that still mint their own handles off a frontend lifetime id -
+        // the debt SlotTables.h records against itself at the top of that file.
+        //
+        // POINTER, not the reference GetOrCreate(StatePtr) returns, and that is deliberate:
+        // this call has THREE ways to decline and every one of them has to be visible to the
+        // caller rather than answered with a parked twin.
+        //   * the legacy arm is running, so there is no slot table to index;
+        //   * the slot is past the table's sanity bound (a corrupt 32-bit slot must not decide
+        //     a vector resize);
+        //   * the generation is BEHIND the live entry's. SlotTables.h:301-321 is the whole
+        //     argument: forward is a recycle and resets the twin, BACKWARD is refused, because
+        //     adopting it would destroy the incumbent LIVE twin's driver ids and then stamp the
+        //     slot back to the dead object's generation - the shape commit d7655247 fixed.
+        // The refusal is SILENT here and gets its release-build voice at the per-kind resolver
+        // in Managers.cpp, exactly as GetOrCreateBufferResourceForHandle gives P3a's.
+        BackendPtr* GetOrCreateByHandle(MG_Pipe::MGPipeHandle handle) {
+            if (!EsprytSlotTablesEnabled()) return nullptr;
+            if (MG_Pipe::MGPipeHandleIsNull(handle)) return nullptr;
+            if (handle.Slot >= SlotTable::kMaxHandleSlot) return nullptr;
+            const Uint32 liveGen = m_slotTable.LiveGenAt(handle.Slot);
+            if (liveGen != 0 && liveGen > handle.Gen) return nullptr;
+            return &m_slotTable.GetOrCreate(handle);
+        }
+
+        // The generation of the LIVE entry at this slot, or 0. It exists so a caller can
+        // DIAGNOSE, in a release build where MOBILEGL_ASSERT is inert, the refusal above
+        // performs silently.
+        Uint32 LiveGenAt(Uint32 slot) const {
+            if (!EsprytSlotTablesEnabled()) return 0;
+            return m_slotTable.LiveGenAt(slot);
+        }
+
+        // NO ReleaseByHandle HERE, AND THAT IS A DECISION (review M-4). The death half of
+        // GetOrCreateByHandle exists for a kind whose announcement is its own destroy CALL
+        // rather than the shared death notice - which is the BUFFER family
+        // (BackendBufferResourceTable::ReleaseByHandle, SlotTables.h, called from
+        // resource_destroy) and none of the five kinds this registry serves: every one of them
+        // dies through DestroyByLifetimeId below, because P4a adds no server-side destroy arm
+        // for a texture, a renderbuffer, a framebuffer, a sampler CSO or a shader CSO. v1
+        // declared one here anyway and it had no caller on either arm, which made its bound and
+        // its wording things nobody would exercise until P5. The one-line wrapper comes back in
+        // the commit that gives it a caller; SlotTable::ReleaseByHandle underneath is untouched
+        // and is what SanityTest drives directly.
+
         // P2 step e2. STATIC, because a death notice is about an object and not about a
         // registry instance: it is answered by EVERY table of this kind that exists - this
         // registry's own, and any by-value copy of it a fixture or a context reset is holding
@@ -552,6 +603,121 @@ namespace MobileGL::MG_Backend::DirectGLES {
     using TwinRegistry = StateBackendObjectRegistry<StateObject, BackendObject>;
 #endif
 
+#if MOBILEGL_PIPE_PUSH
+    // ---- P4a (D-K3): one arm resolver per family, beside BufferImpl's two ----
+    //
+    // Four bits and therefore four resolvers, for P3a's reason one level out: a framebuffer
+    // path that regressed, a texture path that regressed, a sampler path that regressed and a
+    // program path that regressed are four different findings, and clearing one must not
+    // disarm the other three.
+    //
+    // THE RESOLUTION IS LAZY, at the first use, and never at bring-up. Backend context creation
+    // runs inside eglMakeCurrent and the integration harness pre-flights exactly that sequence
+    // in a FORKED CHILD; a child that dies on a signal is reported as "no usable GPU" and every
+    // scenario in the lane is SKIPPED - the lane goes green having run nothing, on the very
+    // pair of env vars the A/B is driven with, which is what ROADMAP.md:7 forbids. So a stop
+    // has to land in a test body, i.e. at the first lookup. That is what the inline latches
+    // below give: a guard-variable load and a perfectly-predicted branch per consult, and the
+    // arm dispatch folds into the caller (SlotTables.h's EsprytSlotTablesEnabled argument
+    // verbatim - every one of these is consulted on the per-draw path).
+    //
+    // ALL FOUR CAN REACH NoArm and all four STOP there rather than skipping green, because
+    // every one of the four legacy arms is compiled under MOBILEGL_PIPE_LEGACY_MEMOS:
+    //   framebuffer  - the four g_fboSynced* arrays and StampSyncedFBO;
+    //   texture      - the twin's m_prevTextureInfo / m_syncedContentVersion cheap-gate trio;
+    //   samplers     - UnitSamplerLookupMemo's WeakPtr arm and SamplerPassMemo's raw
+    //                  BackendSamplerObject* rows;
+    //   programs     - g_programTwinLookupMemo.
+    //
+    // THREE OF THEM CARRY A DEPENDENCY (MGPipe.h, D-K2) and it is diagnosed and REFUSED here
+    // rather than half-run, the bit-8-requires-bit-7 shape ResolveVertexInputSubsystemArm
+    // already ships: bit 11 requires bit 10, bit 9 requires bit 10, bit 10 requires bit 7. The
+    // mirror pairs (10 without 11, 10 without 9, 7 without 10) are all FINE and are said so out
+    // loud, because an unreachable branch that says something different is how the reachable
+    // one drifts. Bit 12 depends on nothing: a ShaderCso handle names no texture and no buffer.
+    //
+    // ResolveFramebufferSubsystemArm additionally carries D-C3's bring-up refusal: the wire
+    // array is MGPFramebufferState::Color[8] and GetDynamicParameters().MaxColorAttachments is
+    // the driver's RAW ES cap, which is not clamped to 8 on this path. A driver reporting more
+    // would silently truncate the record, so the bit is refused with one MGLOG_E naming the cap
+    // and the legacy arm runs. Widening the payload is a wire change nobody has evidence for;
+    // truncating silently is the bug class this phase is closing.
+    Bool ResolveFramebufferSubsystemArm();
+    Bool ResolveTextureResourceSubsystemArm();
+    Bool ResolveSamplerSubsystemArm();
+    Bool ResolveProgramSubsystemArm();
+
+    inline Bool FramebufferSubsystemEnabled() {
+        static const Bool enabled = ResolveFramebufferSubsystemArm();
+        return enabled;
+    }
+    inline Bool TextureResourceSubsystemEnabled() {
+        static const Bool enabled = ResolveTextureResourceSubsystemArm();
+        return enabled;
+    }
+    inline Bool SamplerSubsystemEnabled() {
+        static const Bool enabled = ResolveSamplerSubsystemArm();
+        return enabled;
+    }
+    inline Bool ProgramSubsystemEnabled() {
+        static const Bool enabled = ResolveProgramSubsystemArm();
+        return enabled;
+    }
+
+    // ---- P4a: what the twins read INSTEAD of the frontend object ----
+    //
+    // One reader per record kind, all const, all null-on-miss, and all bounds-checked against
+    // the applier's own dense table rather than against a constant: a slot at or above the
+    // table's size simply has no record, which is the same answer as "not live" and is not a
+    // protocol error on THIS side (the applier already refused and counted the call that would
+    // have created it - PipeApply.h's RefusedObjectCalls).
+    //
+    // A NULL ANSWER IS NOT A FALL-BACK TO THE FRONTEND. On a family's handle arm, quietly
+    // reaching into the frontend object again would hide a missing record behind a picture that
+    // still looks right, which is exactly what the subsystem A/B exists to expose
+    // (MarkBufferGpuWritten's note, P3a). Every caller below either declines the work with a
+    // named MGLOG_E_ONCE or runs its family's LEGACY arm, decided by the family latch and
+    // never per record.
+    //
+    // The returned pointer is into a Vector the applier may grow, so it is valid only until the
+    // next applier call - the same rule the legacy arm's map-into pointers carried, and every
+    // caller here reads what it needs and lets go.
+    const MG_Pipe::MGPipeResourceRecord* PipeTextureRecordForHandle(MG_Pipe::MGPipeHandle res);
+    const MG_Pipe::MGPipeResourceRecord* PipeRenderbufferRecordForHandle(MG_Pipe::MGPipeHandle res);
+    const MG_Pipe::MGPipeSamplerCsoRecord* PipeSamplerCsoRecordForHandle(MG_Pipe::MGPipeHandle cso);
+    const MG_Pipe::MGPipeSamplerViewRecord* PipeSamplerViewRecordForHandle(MG_Pipe::MGPipeHandle view);
+    // ShaderCso is the one kind whose slot space is split in two on the CLIENT side - the
+    // composite band lives in its own dense table so a single program-pipeline composite does
+    // not grow a 983040-entry vector (contract D13). The server never learns a handle is a
+    // composite: this reader hides the split behind one lookup, exactly as the wire does.
+    const MG_Pipe::MGPipeShaderCsoRecord* PipeShaderCsoRecordForHandle(MG_Pipe::MGPipeHandle cso);
+
+    // The pending-upload entry the applier accumulated for this (uploadTarget, level) of this
+    // texture record, or null (D-D5). SERVER-SIDE STATE, and that is the whole point: the
+    // client clears its own dirty flags at EMISSION for the levels the applier accepted, while
+    // Espryt's upload loop has bail arms - an incomplete texture returns early, a multisample
+    // target refreshes and skips - that today leave the frontend flag set. A naive move of the
+    // clear to the client would lose exactly those texels. The set survives any number of
+    // bails; ConsumePipeTextureUpload below is called ONLY where the level actually uploaded.
+    //
+    // `uploadTarget` is static_cast<Uint16>(MobileGL::TextureUploadTarget) - the HALF, not the
+    // packed field. The stored key is MGPSubData::Target whole (low byte MGPipeResourceTarget,
+    // high byte TextureUploadTarget, ID-12) and both functions decode it with
+    // MGPipeSubDataUploadTargetOf; they are the only two places this package compares it.
+    const MG_Pipe::MGPipeResourceRecord::PendingUpload* FindPipeTextureUpload(
+        const MG_Pipe::MGPipeResourceRecord& record, Uint16 uploadTarget, Uint16 level);
+    void ConsumePipeTextureUpload(MG_Pipe::MGPipeHandle res, Uint16 uploadTarget, Uint16 level);
+
+    // THE SERVER'S OWN RE-DIRTY, armed in the applier's set instead of in the frontend's model
+    // (esprytobj review M-1). `packedTarget` is a full MGPSubData::Target built with
+    // MGPipePackSubDataTarget, because the entry this writes has to be indistinguishable from
+    // one the client emitted. Whole-level, no regions, merged with any entry already there;
+    // false (and one named log line) when the applier's pending set is at its bound. The three
+    // server-side MarkStorageDirty sites are enumerated at the definition.
+    Bool RearmPipeTextureLevelUpload(MG_Pipe::MGPipeHandle res, Uint16 packedTarget, Uint16 level,
+                                     const MG_Pipe::MGPBox& wholeLevel);
+#endif
+
     namespace BufferImpl {
         const GLenum TempBufferTarget = GL_ARRAY_BUFFER;
 
@@ -1514,6 +1680,61 @@ namespace MobileGL::MG_Backend::DirectGLES {
             // single-level texture with a mipmapping filter), and an incomplete texture samples
             // (0, 0, 0, 1) rather than its contents.
             Bool m_forceSamplerResync = false;
+#if MOBILEGL_PIPE_PUSH
+            // ---- P4a's handle arm: the two prologues that decide WHETHER there is work and
+            // WHERE the values come from. Both answer null for "nothing to do", which covers
+            // three cases the caller treats identically and the callee names individually in
+            // the log: the record's serial has not moved, this texture has no record at all,
+            // or its params name a sampler CSO the applier does not hold.
+            //
+            // NEITHER FALLS BACK TO THE FRONTEND. On this arm the texture family is switched
+            // over, and quietly re-reading the object would hide a missing record behind a
+            // picture that still looks right - which is precisely what the subsystem A/B exists
+            // to expose (MarkBufferGpuWritten's note, P3a).
+            const SamplerParameters* ResolvePushedBuiltinSampler(
+                const SharedPtr<MG_State::GLState::ITextureObject>& stateTextureObject);
+            // Hands back the whole RECORD rather than its Params, because the parameter push
+            // reads two things from beside them: Desc.InternalFormat, which decides the two
+            // channel-widening swizzle compositions, and Params.BuiltinSampler, which is where
+            // the border colour lives (it is sampler state, GL 4.6 table 23.18, and P4a does
+            // not duplicate it onto MGPTextureParams).
+            const MG_Pipe::MGPipeResourceRecord* ResolvePushedTextureParams(
+                const SharedPtr<MG_State::GLState::ITextureObject>& stateTextureObject);
+
+            // ---- P4a's handle arm (D-B3). Three server-owned serials that REPLACE, on their
+            // own arm, the six frontend-version memos above; the legacy members stay beside
+            // them under MOBILEGL_PIPE_LEGACY_MEMOS because ARCHITECTURE.md:369 keeps the
+            // pre-handle arm compiled through P3a/P4a, and because clearing the family's bit
+            // has to run the pre-handle arm rather than a half-migrated one.
+            //
+            // Inside the guard, so the PULL build's BackendTextureObject is byte-for-byte the
+            // pre-P4a object and G1's admitted-resize set stays empty (D-P).
+            //
+            // 0 is never a real serial - the applier's counters start at 1 and only ever
+            // advance, including across a make-current (PipeApply.cpp's three-way argument) -
+            // so a zeroed memo is a guaranteed miss and a fresh twin owes a full sync.
+
+            // The resource record's Serial at the last completed mipmap sync. It replaces the
+            // whole cheap-gate trio (m_syncedShapeContextId / m_syncedShapeGeneration /
+            // m_syncedShapeParamsVersion) AND m_syncedContentVersion: the applier bumps it on
+            // every respecify and every sub-data it applies to this resource, which is exactly
+            // the union those four covered, without the coarse "any texture's churn re-opens
+            // every gate" behaviour the sampling-resolution generation had.
+            Uint64 m_syncedResourceSerial = 0;
+            // The record's ParamsSerial at the last SyncTextureParamsToBackend. Replaces
+            // m_syncedTextureParamsVersion; MGPTextureParams::ForceResync replaces
+            // m_forceTextureParamsResync and is consumed the same way - read, acted on, and
+            // NOT written back, because the client never clears a server flag and the server
+            // never clears the client's (D-E2, the D-D5 inversion applied to two bits).
+            Uint64 m_syncedParamsSerial = 0;
+            // The BuiltinSampler CSO record's Serial at the last SyncBuiltinSamplerToBackend,
+            // plus the handle it was read through - a texture whose params name a DIFFERENT
+            // CSO than last time has had its sampling state replaced wholesale even if the new
+            // CSO's serial happens to match, which is a real sequence under content addressing
+            // (two textures sharing one CSO, then one of them diverging).
+            Uint64 m_syncedBuiltinSamplerSerial = 0;
+            MG_Pipe::MGPipeHandle m_syncedBuiltinSampler = MG_Pipe::kMGPipeNullHandle;
+#endif
         };
 
         void ActivateTextureUnit(Uint unit);
@@ -1606,11 +1827,64 @@ namespace MobileGL::MG_Backend::DirectGLES {
             // mismatch means some backend texture id was re-minted since, and any of this
             // twin's attachment points may still hold the dead id even though the frontend
             // attachment versions match - so the walk re-attaches everything first.
+            //
+            // SERVER-OWNED AND IT SURVIVES P4a (D-B3). It answers "did *I* re-mint a driver
+            // texture id", which no client-side version can answer; dropping it would
+            // reintroduce exactly the class of bug commit d7655247 fixed on the buffer side.
             Uint64 m_syncedBackendIdGeneration = 0;
+#if MOBILEGL_PIPE_PUSH
+            // P4a (D-C4): MGPFramebufferState::ContentHash as of this twin's last sync, PER
+            // TARGET IT WAS SYNCED AS, and it is the second of the hash's two jobs - "the server's
+            // render-pass memo key, and the CLIENT's emission suppressor". It replaces
+            // m_syncedFrontendAttachmentVersions AS A KEY (the array stays: it is what the
+            // legacy arm compares, and it is the mechanism the handle arm re-arms through).
+            //
+            // The hash covers every field the record carries - Fbo included, so a recycled
+            // framebuffer handle whose successor happens to carry an identical attachment set
+            // can never be suppressed against its predecessor, and DrawBuffers[8] included, so
+            // a suppressed record provably means the draw-buffer array did not move, which
+            // provably means the fragColor broadcast count did not move.
+            //
+            // PER TARGET rather than one, and it stays that way under ID-19's per-OBJECT record:
+            // there is now ONE record for this framebuffer, but syncing it as Draw and syncing it
+            // as Read do different work (glDrawBuffers and the four cross-object masks are
+            // Draw-only, glReadBuffer is Read-only), so "I have already applied this record" is a
+            // per-target claim and one memo would let the second target skip work the first never
+            // did. 0 is never a live hash (a computed 0 is remapped to 1 by the client's
+            // suppressor), so a zeroed memo is a guaranteed miss.
+            Array<Uint64, SizeT(FramebufferTarget::FramebufferTargetCount)> m_syncedRecordHashes = {0};
+#endif
         };
 
         extern TwinRegistry<MG_State::GLState::FramebufferObject, BackendFramebufferObject, MG_Pipe::MGPipeKind::Framebuffer>
             g_backendFramebufferObjects;
+
+#if MOBILEGL_PIPE_PUSH
+        // P4a (D-C2 as corrected by ID-19): the applier's record for THE FRAMEBUFFER OBJECT this
+        // handle names, or null.
+        //
+        // v1 asked the applier for its two BOUND-target working records and answered null unless
+        // one of them happened to name this twin - which meant every DSA entry point
+        // (BlitNamedFramebuffer, the four ClearNamedFramebuffer*) drove a framebuffer that is
+        // bound to neither target, found no record, declined, and then had the clear or blit
+        // issued against a driver FBO that never got its attachments. The record is now keyed by
+        // the framebuffer HANDLE (MGPipeApplierState::FramebufferRecords, wire v3), so a record
+        // that comes back is this framebuffer's by construction and it comes back whether the
+        // object is bound to Draw, to Read, to both or to neither. A null here means "no emission
+        // has ever described this framebuffer, or the handle's generation is stale" - both of
+        // them seam defects on an integrated tree, never a binding question.
+        //
+        // `fbo` is the handle the caller resolved for this twin; passing it in rather than
+        // resolving it here keeps the monolith-glue lookup at one site per sync.
+        const MG_Pipe::MGPFramebufferState* PushedFramebufferRecord(MG_Pipe::MGPipeHandle fbo);
+
+        // THE BINDING QUESTION, WHICH IS NOW A DIFFERENT QUESTION FROM THE DESCRIPTION (ID-19(d)):
+        // "is the framebuffer this handle names the one bound to `target`". One array compare
+        // against MGPipeApplierState::BoundFramebuffer, never a record lookup - a Named record
+        // describes an object without claiming any binding for it, so asking the record would
+        // give the wrong answer by construction.
+        Bool PushedFramebufferIsBoundTo(FramebufferTarget target, MG_Pipe::MGPipeHandle fbo);
+#endif
         // True when the read buffer names a fixed-point (norm/snorm) attachment that the
         // backend actually stores in a floating-point format. GL clamps a read from a
         // fixed-point colour buffer to [0,1] (GL_CLAMP_READ_COLOR defaults to
@@ -1704,6 +1978,16 @@ namespace MobileGL::MG_Backend::DirectGLES {
         // the driver FBO would keep the deleted texture name attached forever. The
         // SyncCurrentFBO gate compares this generation (below) to re-enter the sync,
         // and each twin re-arms its per-attachment memo on a mismatch (SyncToBackend).
+        //
+        // AND WHENEVER AN ATTACHABLE OBJECT'S DRIVER STORAGE IS REDEFINED IN PLACE (P4a fable
+        // seam F-3): a mutable texture regenerated on the same id, a renderbuffer re-storaged
+        // on the same id. The id did not move, but the four cross-object masks SyncToBackend
+        // computes from the attachment's format did, and nothing else the FBO memo reads sees
+        // a respecify of an attached object. So "did I change something under an attachment
+        // point that no frontend version can tell the framebuffer about" is what this counts,
+        // and the re-mint is one case of it. The in-place bumps are compiled under
+        // MOBILEGL_PIPE_PUSH: G1 keeps the pull library byte-identical to the P4a baseline,
+        // so the pull build keeps the pre-P4a hole until they land on dev on their own.
         extern Uint64 g_attachmentBackendIdGeneration;
         // What g_attachmentBackendIdGeneration was when SyncCurrentFBO last stamped each
         // target; part of the synced tuple above.
@@ -1718,6 +2002,27 @@ namespace MobileGL::MG_Backend::DirectGLES {
         // GL_FRAMEBUFFER binds both targets.
         void BindFramebufferId(GLenum fbTarget, Uint id);
         Uint CurrentFramebufferBinding(FramebufferTarget target);
+#if MOBILEGL_PIPE_PUSH
+        // THE HANDLE ARM'S OWN FRAMEBUFFER MEMOS, AND THEY ARE PACKAGE E's STORAGE
+        // (DirectGLES.cpp: g_fboSyncedSerials, g_fboRecordsTrusted). E's review MAJOR-4 handed
+        // this to D because InvalidateFramebufferBindingCache is in THIS file and has three
+        // callers E cannot reach - MG_Test/SanityTest.cpp's ScopedStateGuardMocks::ResetShadows
+        // and ScopedBackendTwinMocks' constructor and destructor - which clear the pre-handle
+        // trio and would leave the handle-arm memos claiming a target is synced across a GLES
+        // function-table swap. Calling it from INSIDE InvalidateFramebufferBindingCache is what
+        // makes forgetting impossible, and that call is written below.
+        //
+        // IT IS GATED, AND HERE IS THE HANDSHAKE, because the definition is `static` in E's file
+        // on the tree this package was built against (esprytdraw v2, DirectGLES.cpp:2789) and an
+        // internal-linkage function cannot be called from Managers.cpp. E's verification round
+        // drops that one keyword; D's verification round flips this constant to 1, in this file,
+        // one line. Neither side can do it silently: the flip has no other reader and the
+        // declaration below has no other definition.
+#define MOBILEGL_ESPRYT_FBO_HANDLE_ARM_MEMOS_LINKED 0
+#if MOBILEGL_ESPRYT_FBO_HANDLE_ARM_MEMOS_LINKED
+        void InvalidateFramebufferHandleArmMemos();
+#endif
+#endif
         void InvalidateFramebufferBindingCache();
         // A driver framebuffer id is about to be deleted: ES reverts every target that
         // currently binds it to 0, so the binding shadow has to follow or the next
@@ -2009,6 +2314,22 @@ namespace MobileGL::MG_Backend::DirectGLES {
             // stale as one built before a relink - while the sampler half, which really is
             // re-issued per draw, needs nothing of the sort.
             Uint32 GetSyncedImageUnitVersion() const { return m_syncedImageUnitVersion; }
+#if MOBILEGL_PIPE_PUSH
+            // P4a (D-B3, D-H5): the ShaderCso record's Serial this backend program was built
+            // from. It is what the draw path's nine-clause rebuild condition reads on the handle
+            // arm INSTEAD OF the two frontend versions above - one server-owned counter that
+            // moves on every create_shader_state the applier applies to this handle, including a
+            // RE-create on the same handle, which is how a relink travels (Gen moves only on slot
+            // reuse, never on a respecify).
+            //
+            // THE CLAUSE COUNT DOES NOT SHRINK, and a brief that treated create_shader_state as
+            // self-contained would produce a per-draw rebuild: the other eight inputs - the draw
+            // FBO's snorm/unorm clamp masks, the fragColor broadcast count, the storage-block
+            // binding signature, the atomic-counter set, the live image formats and the patch
+            // parameters - are all still specialised at the verb, from state this backend holds.
+            // 0 means "never stamped", which is a guaranteed miss (applier serials start at 1).
+            Uint64 GetSyncedShaderCsoSerial() const { return m_syncedShaderCsoSerial; }
+#endif
             // Whether the (unit, bound format) pairs this program's FORMAT-LESS image uniforms
             // resolve to are still the ones its ESSL was generated against.
             //
@@ -2108,6 +2429,11 @@ namespace MobileGL::MG_Backend::DirectGLES {
             BufferImpl::UboRingAllocation m_globalUboRingAllocation;
             Uint32 m_syncedLinkVersion = ~0u;
             Uint32 m_syncedImageUnitVersion = ~0u;
+#if MOBILEGL_PIPE_PUSH
+            // P4a's replacement for the two above on the handle arm; see GetSyncedShaderCsoSerial.
+            // Push-only, so the pull build's object is byte-for-byte the pre-P4a one (D-P).
+            Uint64 m_syncedShaderCsoSerial = 0;
+#endif
             // Image units addressed by the program's FORMAT-LESS image uniforms, and the digest
             // of the (unit, format) pairs the generated ESSL baked. Empty/0 for every program
             // that declares a format on all of its images, which is the overwhelming majority -
@@ -2211,7 +2537,32 @@ namespace MobileGL::MG_Backend::DirectGLES {
             ~BackendSamplerObject();
             BackendSamplerObject(const BackendSamplerObject&) = delete;
             BackendSamplerObject& operator=(const BackendSamplerObject&) = delete;
+#if MOBILEGL_PIPE_PUSH
+            // THE SAMPLER CSO HANDLE IS CARRIED BY THE CALLER, and it has to be, because a
+            // SamplerCso is CONTENT-ADDRESSED on the client (D-F1) while this twin is keyed on
+            // the frontend OBJECT. g_backendSamplerObjects mints a SamplerCso slot off the
+            // SamplerObject's lifetime id - that handle is this twin's identity and is what
+            // FindByHandle memos index - but the client's cache allocates its handles by
+            // CONTENT (MGPipeSlots().Allocate, SamplerEmit.h), so no create_sampler_state ever
+            // lands at the identity handle and looking a record up by it can only ever miss.
+            // The carried fact that DOES name the right record is the applier's own
+            // MGPipeApplier().BoundSamplerStates[unit], which the client writes per unit at
+            // bind_sampler_states; the caller that knows the unit passes it here.
+            //
+            // Defaulted so a caller that has no unit - the backend's OWN raw-depth-fetch
+            // sampler (DirectGLES.cpp:217), a SamplerObject the client has never seen and for
+            // which no record can exist - keeps working: that arm reads the object, which is
+            // the authority for server-owned state. An APPLICATION sampler reaching here
+            // without a handle is the E-side call-site gap and says so once.
+            //
+            // Push-only spelling on purpose: a defaulted parameter is still part of the
+            // signature, so widening it unconditionally would rename this symbol in the PULL
+            // build and P4a's admitted-change set is EMPTY (D-P/G1).
+            void SyncToBackend(const SharedPtr<MG_State::GLState::SamplerObject>& stateSamplerObject,
+                               MG_Pipe::MGPipeHandle pushedCso = MG_Pipe::kMGPipeNullHandle);
+#else
             void SyncToBackend(const SharedPtr<MG_State::GLState::SamplerObject>& stateSamplerObject);
+#endif
             void Bind(Uint unit);
             Uint GetBackendSamplerId() const;
 
@@ -2221,6 +2572,19 @@ namespace MobileGL::MG_Backend::DirectGLES {
             Bool m_isInitialized = false;
             SamplerParameters m_cacheSamplerParameters;
             Uint16 m_syncedSamplerVersion = 0;
+#if MOBILEGL_PIPE_PUSH
+            // P4a (D-B3): the SamplerCso record's Serial at the last completed sync. It replaces
+            // m_syncedSamplerVersion, which stays beside it because the pre-handle arm compiles
+            // under MOBILEGL_PIPE_LEGACY_MEMOS through P3a/P4a (ARCHITECTURE.md:369).
+            //
+            // The two are not interchangeable and that is the point: the frontend version is per
+            // OBJECT, while the serial is per CONTENT-ADDRESSED CSO, and two frontend samplers
+            // with identical parameters share one CSO and therefore one serial - so under the
+            // handle arm the second of them costs no driver call at all.
+            //
+            // Push-only, so the pull build's object is byte-for-byte the pre-P4a one (D-P).
+            Uint64 m_syncedSamplerSerial = 0;
+#endif
         };
 
         void UnbindSampler(Uint unit);
@@ -2229,8 +2593,108 @@ namespace MobileGL::MG_Backend::DirectGLES {
             g_boundSamplersCache;
         extern TwinRegistry<MG_State::GLState::SamplerObject, BackendSamplerObject, MG_Pipe::MGPipeKind::SamplerCso>
             g_backendSamplerObjects;
+
+#if MOBILEGL_PIPE_PUSH
+        // P4a FABLE SEAM F-4: THE TWIN FOR A CONTENT-ADDRESSED SamplerCso HANDLE.
+        //
+        // bind_sampler_states carries, per unit, the handle of a CSO the client allocated BY
+        // CONTENT (SamplerEmit.h: MGPipeSlots().Allocate with no lifetime id), while every twin
+        // in g_backendSamplerObjects was minted off a SamplerObject's lifetime id - two disjoint
+        // slot families out of one allocator. So `g_backendSamplerObjects.FindByHandle(
+        // BoundSamplerStates[unit])` (the record arm of BindCurrentUnitSamplers, E's S4) could
+        // never find a twin, the record arm bound nothing on every draw, and every glBindSampler
+        // reached the driver only through the pre-handle program pass - S-1's confusion one
+        // loop over, and exactly what SamplerEmit.h:201-205 forbids ("a backend must NOT key a
+        // sampler twin on a SamplerObject's lifetime id; the twin's life is
+        // create_sampler_state -> delete_sampler_state").
+        //
+        // This is the twin keyed the way the record is: resolved-or-created AT THE CSO HANDLE
+        // (GetOrCreateByHandle, the same slot table, a slot the identity family can never hold)
+        // and synced from the record it names, serial-gated. Two callers bind it - the record
+        // arm of BindCurrentUnitSamplers and the program pass's sampler override - so the two
+        // cannot ping-pong the unit between an identity twin and a CSO twin. Its death is the
+        // slot's recycle: the client's LRU eviction drops the record and frees the slot, and
+        // the next handout at that slot arrives with a moved generation, which GetOrCreate(
+        // handle) answers by resetting the twin (the driver sampler goes with it). A twin for
+        // an evicted CSO therefore lives until its slot is reused - bounded by the cache's
+        // capacity, never by draw count - and there is no delete_sampler_state hook to retire it
+        // earlier; the ops table carries none for this kind.
+        //
+        // Null, loudly, when the handle names no record (a client seam) or cannot be adopted
+        // (a generation behind the slot's live entry); null silently for the null handle. The
+        // pre-handle arm - a twin keyed on the frontend object - is untouched and still serves
+        // the raw-depth-fetch sampler and every caller that carries no handle.
+        BackendSamplerObject* ResolveSamplerCsoTwin(MG_Pipe::MGPipeHandle cso);
+#endif
     } // namespace SamplerImpl
 
+#if MOBILEGL_PIPE_PUSH
+    namespace SamplerViewImpl {
+        // P4a (D-F2/D-F3): the SIXTH Espryt twin table, and the only one of the six whose kind
+        // has no frontend object at all. MobileGL has no sampler-view class: GL binds a texture
+        // to a unit and the sampler uniform's type, the mipmap-completeness predicates and
+        // IsUndefinedDefaultTexture decide what the shader sees. Gallium's one-view-per-slot IS
+        // that resolved form, the resolution moves to the CLIENT (ARCHITECTURE.md:206), and
+        // create_sampler_view carries the restrictions the resolution had to read.
+        //
+        // So this twin owns NO DRIVER ID. There is nothing in ES to create for a view; the id
+        // the unit binds is the texture's, and it lives on BackendTextureObject. What this twin
+        // is, is the server's MEMO of one resolved view: the record it was built from, keyed on
+        // that record's serial, plus the two BACKEND-SPECIFIC POST-PROCESSINGS
+        // ARCHITECTURE.md:206 keeps on the server and which act on the already-resolved set.
+        // Espryt's is the raw-depth-fetch sampler substitution; Magma's feedback-loop detection
+        // is its own and is not here.
+        //
+        // A twin with no driver id still earns a table: it is what turns "re-derive the
+        // substitution decision for every sampled unit of every draw" into one serial compare,
+        // and it is the slot space the client's per-texture SamplerViewCso handle indexes.
+        // There is deliberately no destructor: nothing here owns a GPU object, so the teardown
+        // sentinel's whole reason (a twin destructor must not call into an unloaded driver)
+        // does not apply and the default one is correct in every teardown order.
+        struct BackendSamplerViewObject {
+            // The view record as last synced, verbatim. Reading it here rather than re-asking
+            // the applier is what lets a caller hold the twin across another applier call.
+            MG_Pipe::MGPSamplerView View{};
+            // The applier record's Serial this memo was built from. 0 = never synced, and 0 is
+            // never a real serial (the applier's counters start at 1), so a zeroed memo is a
+            // guaranteed miss.
+            Uint64 SyncedSerial = 0;
+            // Espryt's post-processing, decided from the RESOLVED set: the view's
+            // InternalFormat answers IsDepthFormatInternalFormat and the sampler CSO record's
+            // SamplerParameters answer compareMode / minFilter / mipmapMode / magFilter. The
+            // decision is re-derived when either serial moves; the sampler serial is kept
+            // beside it so a sampler mutation alone re-derives it.
+            Uint64 SyncedSamplerSerial = 0;
+            Bool NeedsRawDepthFetchSampler = false;
+        };
+
+        // Handle-keyed ONLY, exactly like P3a's BackendBufferResourceTable: the StateObject
+        // parameter names ITextureObject because the template names one and because the view is
+        // minted off the TEXTURE's lifetime id (D-F2: one view per ITextureObject), which is
+        // what makes HandleOf below resolve at all. Not one member that would dereference it is
+        // instantiated - no Find(StateObject*), no ForEachLive - and the handle overloads never
+        // look at it.
+        using BackendSamplerViewTable = BackendSlotTable<MG_State::GLState::ITextureObject,
+                                                        BackendSamplerViewObject,
+                                                        MG_Pipe::MGPipeKind::SamplerViewCso>;
+        extern BackendSamplerViewTable g_backendSamplerViews;
+
+        // Resolve-or-create / resolve-only by the handle the call carried. Neither touches
+        // MGPipeSlots(): the handle ARRIVED, already minted by the side that owns minting.
+        BackendSamplerViewObject* GetOrCreateSamplerViewForHandle(MG_Pipe::MGPipeHandle view);
+        BackendSamplerViewObject* FindSamplerViewForHandle(MG_Pipe::MGPipeHandle view);
+
+        // MONOLITH GLUE, and named as such, the HandleOfBuffer shape: the SamplerViewCso handle
+        // of a texture this backend is looking at through a frontend object. Legal only because
+        // the view is minted off the texture's own lifetime id; under a real split neither the
+        // object nor its lifetime id exists on this side and the handle has to arrive in the
+        // payload (which, for every path P4a switches over, it does - this is for the paths
+        // P3b/P4b still owns).
+        MG_Pipe::MGPipeHandle HandleOfSamplerViewForTexture(
+            const MG_State::GLState::ITextureObject* textureObject);
+    } // namespace SamplerViewImpl
+#endif
+
     namespace RenderbufferImpl {
         class BackendRenderbufferObject {
         public:
@@ -2252,6 +2716,20 @@ namespace MobileGL::MG_Backend::DirectGLES {
             Int m_cacheWidth = 0;
             Int m_cacheHeight = 0;
             Int m_cacheSamples = 0;
+#if MOBILEGL_PIPE_PUSH
+            // P4a (D-D2/D-B3): the resource record's Serial at the last completed allocation.
+            // It replaces the four-field cache above AS A GATE - the four members stay, because
+            // they are also what the legacy arm compares and what the twin reports about the
+            // storage it actually holds - and it closes the publication hole D-D2 names:
+            // RenderbufferObject::{SetInternalFormat, AllocateStorage, SetSamples} bump no
+            // version and raise no notice, so `glBindRenderbuffer; glRenderbufferStorage(new)`
+            // on an ALREADY-ATTACHED renderbuffer moved nothing the framebuffer bit could see.
+            // The client now emits resource_respecify straight from those three mutators, the
+            // applier bumps this serial, and one compare here sees it.
+            //
+            // Push-only, so the pull build's object is byte-for-byte the pre-P4a one (D-P).
+            Uint64 m_syncedResourceSerial = 0;
+#endif
         };
 
         extern TwinRegistry<MG_State::GLState::RenderbufferObject, BackendRenderbufferObject, MG_Pipe::MGPipeKind::Renderbuffer>

MobileGL/MG_Backend/DirectVulkan/Renderer/MagmaPipeArms.h

@@ -194,10 +194,115 @@ namespace MobileGL::MG_Backend::DirectVulkan {
     //
     // Off by default (Config.h), set only by the HandleRecycle AbaControl ctest lanes, and
     // #if MOBILEGL_PIPE_PUSH throughout, so no shipping pull build can even parse it.
+    // P4a (BRIEF-P4A.md D-I2, G8): WHICH KINDS THIS ANSWER COVERS, and it is not "all of them".
+    //
+    // P4a mints six more client-side kinds - Texture, Renderbuffer, Framebuffer, SamplerCso,
+    // SamplerViewCso and ShaderCso - and requires the ABA control to defeat "the identity half
+    // of P4a's memo keys as well", because a control that only defeats the guards a phase
+    // RETIRED says nothing about the key that phase SHIPS.
+    //
+    // On Magma there is no such key to defeat, and that is a fact about the roadmap rather than
+    // an omission here. MagmaPipeIdentityTables below mints exactly TWO kinds,
+    // VertexElementsCso and Buffer; a texture, a framebuffer, a sampler, a view and a program
+    // are all still reached from their frontend objects on this backend, and moving them onto
+    // handles is P7's work (ROADMAP.md:24 - "Magma anything"; P4a leaves MG_Backend/DirectVulkan
+    // untouched apart from this file). So the honest statement is per KIND, and it is spelled as
+    // code rather than as a comment so that a caller cannot read the blanket answer above and
+    // conclude the knob covers its kind:
+    //
+    //   * for the two kinds this backend really keys on {slot, gen}, the knob defeats the
+    //     identity exactly as it always has (MagmaPipeClaimSlotMemos);
+    //   * for P4a's six there is nothing here to defeat, so the answer is FALSE - and
+    //     MG_IntegrationTest's HandleRecycleScenario reads that through its own build probe and
+    //     makes those cases' AbaControl arm assert the CORRECT pixels while SAYING that it is
+    //     not controlling anything for that kind. It does not assert a corruption that no code
+    //     on this tree can produce, which would be a permanently red always-on lane.
+    //
+    // WHAT MAKES IT TRUE LATER, in one sentence, so the next reader does not have to derive it:
+    // when a backend grows a Features.PipeHandleAbaControl consumer over its P4a object slot
+    // tables - one `if` in GetOrCreate / FindByHandle, the shape MagmaPipeClaimSlotMemos already
+    // has for vertex input - this function's per-kind answer becomes that consumer's, the
+    // integration probe finds the consumer, and the six cases flip to expecting the corruption.
     inline Bool MagmaPipeAbaControlDefeatsIdentity() {
         return MG_Config::Features.PipeHandleAbaControl;
     }
 
+    // WHICH KINDS THIS BACKEND ACTUALLY KEYS ON {slot, gen}, and therefore which kinds the knob
+    // above has an identity to defeat at all. `kind` is MG_Pipe::MGPipeKind.
+    //
+    // EXHAUSTIVE, WITH NO `default:`, for MG_IntegrationTest/Harness/PipeSlotPeek.cpp's reason:
+    // a kind added to MGPipeKind without a decision here must be a -Wswitch warning in this
+    // file rather than a row that silently inherits somebody else's answer. Being wrong in the
+    // "covered" direction is the expensive one - a control asserting a corruption nobody can
+    // produce is a permanently red always-on lane - so an undecided kind must never read true,
+    // and with no `default:` there is no arm for it to read true from.
+    //
+    // constexpr AND PINNED BY static_assert BELOW, which is what stops it rotting the way a
+    // predicate with no caller does: MagmaPipeIdentityTables mints exactly two kinds, the
+    // asserts say so in both directions, and the file no longer compiles if the tables and this
+    // statement of them ever part company. (Review F-m5: the earlier form had no caller at all
+    // and could not make anything red or green.)
+    inline constexpr Bool MagmaPipeAbaControlKindIsRekeyedHere(MG_Pipe::MGPipeKind kind) {
+        switch (kind) {
+            // The two MagmaPipeIdentityTables really mints.
+            case MG_Pipe::MGPipeKind::VertexElementsCso:
+            case MG_Pipe::MGPipeKind::Buffer:
+                return true;
+            // P4a's six object classes: still reached from their frontend objects on this
+            // backend (Magma's object paths are P7, ROADMAP.md:24), so there is no key here for
+            // the knob to defeat.
+            case MG_Pipe::MGPipeKind::Texture:
+            case MG_Pipe::MGPipeKind::Renderbuffer:
+            case MG_Pipe::MGPipeKind::Framebuffer:
+            case MG_Pipe::MGPipeKind::SamplerCso:
+            case MG_Pipe::MGPipeKind::SamplerViewCso:
+            case MG_Pipe::MGPipeKind::ShaderCso:
+            // ...and everything else this backend does not mint a handle for.
+            case MG_Pipe::MGPipeKind::None:
+            case MG_Pipe::MGPipeKind::Xfb:
+            case MG_Pipe::MGPipeKind::RenderStateCso:
+            case MG_Pipe::MGPipeKind::Fence:
+            case MG_Pipe::MGPipeKind::Query:
+            case MG_Pipe::MGPipeKind::Context:
+            case MG_Pipe::MGPipeKind::KindCount:
+                return false;
+        }
+        return false;
+    }
+
+    static_assert(MagmaPipeAbaControlKindIsRekeyedHere(MG_Pipe::MGPipeKind::VertexElementsCso),
+                  "MagmaPipeIdentityTables mints VertexElementsCso: the knob has an identity to "
+                  "defeat for it");
+    static_assert(MagmaPipeAbaControlKindIsRekeyedHere(MG_Pipe::MGPipeKind::Buffer),
+                  "MagmaPipeIdentityTables mints Buffer: the knob has an identity to defeat for it");
+    static_assert(!MagmaPipeAbaControlKindIsRekeyedHere(MG_Pipe::MGPipeKind::Texture) &&
+                      !MagmaPipeAbaControlKindIsRekeyedHere(MG_Pipe::MGPipeKind::Renderbuffer) &&
+                      !MagmaPipeAbaControlKindIsRekeyedHere(MG_Pipe::MGPipeKind::Framebuffer) &&
+                      !MagmaPipeAbaControlKindIsRekeyedHere(MG_Pipe::MGPipeKind::SamplerCso) &&
+                      !MagmaPipeAbaControlKindIsRekeyedHere(MG_Pipe::MGPipeKind::SamplerViewCso) &&
+                      !MagmaPipeAbaControlKindIsRekeyedHere(MG_Pipe::MGPipeKind::ShaderCso),
+                  "P4a's six object classes are not keyed on {slot, gen} on this backend, so "
+                  "HandleRecycleScenario's six AbaControl arms must NOT expect a corruption here. "
+                  "Wiring one of them is what flips this assert, this predicate and that arm - and "
+                  "MG_IntegrationTest's two-symbol probe over MG_Backend/DirectVulkan is what "
+                  "carries the answer into the lane");
+
+    // THERE IS DELIBERATELY NO PER-KIND WRAPPER HERE, and review F-v2-m3 is why. An earlier
+    // round carried `MagmaPipeAbaControlCoversKind(kind)` - the conjunction of the two
+    // statements above - and it had no caller anywhere in the tree: the knob's only two
+    // consumers (VulkanRenderer.cpp's VAO draw memo and VertexInputStateFactory.cpp's pipeline
+    // key) each hold ONE kind, VertexElementsCso, by construction, so the kind is not a
+    // variable at either site. A conjunction no build ever evaluates cannot be pinned the way
+    // the predicate above is pinned - it is not constexpr, because it reads MG_Config::Features,
+    // so no static_assert can reach it - which makes it exactly the rot F-m5 was raised about,
+    // one level up: an `&&` whose operands could be inverted or dropped with nothing to say so.
+    //
+    // The two pieces stand alone instead, and each is pinned by something that runs:
+    // MagmaPipeAbaControlKindIsRekeyedHere is constexpr and asserted in BOTH directions by the
+    // three static_asserts above, which compile in every Magma build; MagmaPipeAbaControlDefeats
+    // Identity is the knob, and its two consumers are what make it true or false. A call site
+    // that ever does hold a variable kind writes the `&&` there, where a build will run it.
+
     // The single consumer-table entry every VAO collapses onto while the control is on. Slot
     // 0 is a real, ordinary entry of both tables (MagmaPipeSlotIndex maps the first allocatable
     // handle onto it), so nothing about the tables changes shape for the control's sake.

MobileGL/MG_Impl/GLImpl/Framebuffer/GL_Framebuffer.cpp

@@ -16,6 +16,14 @@
 #include <MG_Impl/GLImpl/Getter/GL_Getter.h>
 #include <MG_State/GLState/ErrorState/Error.h>
 #include <MG_Impl/Pipe/PipeFill.h>
+#if MOBILEGL_PIPE_PUSH
+// P4a, ID-19(c). This file is the ONLY place every DSA framebuffer entry point lives, and the
+// emitter it reaches is this package's own header rather than a declaration in one of the
+// contract's: MG_Pipe/PipeMutation.h is the door MG_State has into the client and carries no
+// framebuffer row, and MG_Impl/GLImpl and MG_Impl/Pipe are the same layer (this file already
+// includes MG_Impl/Pipe/PipeFill.h for MGP_FILL).
+#include <MG_Impl/Pipe/FramebufferEmit.h>
+#endif
 #include <MG_Util/Converters/GLToStr/GLEnumConverter.h>
 #include <MG_Util/Converters/GLToMG/TextureEnumConverter.h>
 #include <MG_Util/Converters/MGToMG/TextureEnumConverter.h>
@@ -613,6 +621,35 @@ namespace MobileGL::MG_Impl::GLImpl {
 
             framebufferObject->AttachTexture(attachmentType, textureObject, textureUploadTarget, level, 0, layered);
         }
+#if MOBILEGL_PIPE_PUSH
+        // P4a, ID-19(c): ANY FRAMEBUFFER THE SERVER IS ABOUT TO RECEIVE BY NAME HAS A RECORD.
+        //
+        // The applier keeps framebuffer records PER OBJECT, keyed by the handle - but before
+        // ID-19 it held only the two BOUND-target records, and the emitter only ever built them
+        // at the validate point out of the two bindings. So glClearNamedFramebufferfv(fbo) or
+        // glBlitNamedFramebuffer(..., fbo, ...) on an fbo bound to NEITHER binding reached a
+        // backend that minted a fresh driver framebuffer with no attachments, found no record
+        // for it, declined, and issued the clear against it anyway: GL_INVALID_FRAMEBUFFER_-
+        // OPERATION and nothing cleared, where the legacy arm cleared correctly.
+        //
+        // TWO CLASSES OF SITE call this, and both are "the point at which the object is final
+        // for this call": the five CONSUMERS (blit and the four clears) publish immediately
+        // before MGP_FILL, so the record precedes the verb that hands the object over and a
+        // later bound-target record for the same object still wins; the ten MUTATORS (the DSA
+        // attachment, draw-buffer and read-buffer setters) publish immediately after the
+        // frontend mutation, because they have no validate point at all - FillPoints.def has no
+        // verb for any of them, so there is no MGP_FILL to sit in front of.
+        //
+        // A CALL THAT MOVED NOTHING IS FREE: the record's ContentHash is the emitter's own
+        // suppressor and it is keyed per framebuffer object, so a redundant publish emits zero
+        // bytes. EmitFramebufferByName picks Draw/Read/Both over Named when the object IS
+        // bound, so a Named record can never overwrite a bound record's Target underneath the
+        // binding that resolves through it.
+        void PipePublishFramebufferByName(const SharedPtr<MG_State::GLState::FramebufferObject>& fbo) {
+            if (!fbo) return;
+            MG_Pipe::MGPipeFramebufferEmitterInstance().EmitFramebufferByName(*fbo);
+        }
+#endif
     } // namespace
 
     void BlitFramebuffer_Backend(GLint srcX0, GLint srcY0, GLint srcX1, GLint srcY1, GLint dstX0, GLint dstY0,
@@ -631,6 +668,10 @@ namespace MobileGL::MG_Impl::GLImpl {
             MGLOG_E_ONCE("glBlitNamedFramebuffer skipped: backend does not implement explicit framebuffer blit.");
             return;
         }
+#if MOBILEGL_PIPE_PUSH
+        PipePublishFramebufferByName(readFramebuffer);
+        PipePublishFramebufferByName(drawFramebuffer);
+#endif
         MGP_FILL(BlitNamedFramebuffer);
         blitNamedFramebuffer(readFramebuffer, drawFramebuffer, srcX0, srcY0, srcX1, srcY1, dstX0, dstY0, dstX1,
                              dstY1, mask, filter);
@@ -643,6 +684,9 @@ namespace MobileGL::MG_Impl::GLImpl {
             MGLOG_E_ONCE("glClearNamedFramebufferfv skipped: backend does not implement explicit framebuffer clear.");
             return;
         }
+#if MOBILEGL_PIPE_PUSH
+        PipePublishFramebufferByName(framebuffer);
+#endif
         MGP_FILL(ClearNamedFramebufferfv);
         clearNamedFramebufferfv(framebuffer, buffer, drawbuffer, value);
     }
@@ -654,6 +698,9 @@ namespace MobileGL::MG_Impl::GLImpl {
             MGLOG_E_ONCE("glClearNamedFramebufferfi skipped: backend does not implement explicit framebuffer clear.");
             return;
         }
+#if MOBILEGL_PIPE_PUSH
+        PipePublishFramebufferByName(framebuffer);
+#endif
         MGP_FILL(ClearNamedFramebufferfi);
         clearNamedFramebufferfi(framebuffer, buffer, drawbuffer, depth, stencil);
     }
@@ -665,6 +712,9 @@ namespace MobileGL::MG_Impl::GLImpl {
             MGLOG_E_ONCE("glClearNamedFramebufferiv skipped: backend does not implement explicit framebuffer clear.");
             return;
         }
+#if MOBILEGL_PIPE_PUSH
+        PipePublishFramebufferByName(framebuffer);
+#endif
         MGP_FILL(ClearNamedFramebufferiv);
         clearNamedFramebufferiv(framebuffer, buffer, drawbuffer, value);
     }
@@ -676,6 +726,9 @@ namespace MobileGL::MG_Impl::GLImpl {
             MGLOG_E_ONCE("glClearNamedFramebufferuiv skipped: backend does not implement explicit framebuffer clear.");
             return;
         }
+#if MOBILEGL_PIPE_PUSH
+        PipePublishFramebufferByName(framebuffer);
+#endif
         MGP_FILL(ClearNamedFramebufferuiv);
         clearNamedFramebufferuiv(framebuffer, buffer, drawbuffer, value);
     }
@@ -1404,6 +1457,9 @@ namespace MobileGL::MG_Impl::GLImpl {
 
         if (texture == 0) {
             framebufferObject->Detach(attachmentType);
+#if MOBILEGL_PIPE_PUSH
+        PipePublishFramebufferByName(framebufferObject);
+#endif
             return;
         }
 
@@ -1430,6 +1486,9 @@ namespace MobileGL::MG_Impl::GLImpl {
         }
 
         framebufferObject->AttachTexture(attachmentType, textureObject, textureUploadTarget, level, 0, layered);
+#if MOBILEGL_PIPE_PUSH
+        PipePublishFramebufferByName(framebufferObject);
+#endif
     }
 
     void NamedFramebufferTextureWithUploadTarget_State(const char* functionName, GLuint framebuffer, GLenum attachment,
@@ -1453,6 +1512,9 @@ namespace MobileGL::MG_Impl::GLImpl {
 
         if (texture == 0) {
             framebufferObject->Detach(attachmentType);
+#if MOBILEGL_PIPE_PUSH
+        PipePublishFramebufferByName(framebufferObject);
+#endif
             return;
         }
 
@@ -1480,6 +1542,9 @@ namespace MobileGL::MG_Impl::GLImpl {
         }
 
         framebufferObject->AttachTexture(attachmentType, textureObject, textureUploadTarget, level);
+#if MOBILEGL_PIPE_PUSH
+        PipePublishFramebufferByName(framebufferObject);
+#endif
     }
 
     void NamedFramebufferTexture1D_State(GLuint framebuffer, GLenum attachment, GLenum textarget, GLuint texture,
@@ -1534,6 +1599,9 @@ namespace MobileGL::MG_Impl::GLImpl {
 
         if (texture == 0) {
             framebufferObject->Detach(attachmentType);
+#if MOBILEGL_PIPE_PUSH
+        PipePublishFramebufferByName(framebufferObject);
+#endif
             return;
         }
 
@@ -1636,6 +1704,9 @@ namespace MobileGL::MG_Impl::GLImpl {
 
         framebufferObject->AttachTexture(attachmentType, textureObject, textureUploadTarget, level, layer,
                                          /*layered=*/false);
+#if MOBILEGL_PIPE_PUSH
+        PipePublishFramebufferByName(framebufferObject);
+#endif
     }
 
     void FramebufferRenderbuffer_State(GLenum target, GLenum attachment, GLenum renderbuffertarget,
@@ -1705,6 +1776,9 @@ namespace MobileGL::MG_Impl::GLImpl {
 
         if (renderbuffer == 0) {
             framebufferObject->Detach(attachmentType);
+#if MOBILEGL_PIPE_PUSH
+        PipePublishFramebufferByName(framebufferObject);
+#endif
             return;
         }
 
@@ -1714,6 +1788,9 @@ namespace MobileGL::MG_Impl::GLImpl {
         if (!renderbufferObject) return;
 
         framebufferObject->AttachRenderbuffer(attachmentType, renderbufferObject);
+#if MOBILEGL_PIPE_PUSH
+        PipePublishFramebufferByName(framebufferObject);
+#endif
     }
 
     void DrawBuffersForFramebuffer_State(const SharedPtr<MG_State::GLState::FramebufferObject>& fbo, Bool isDefaultFBO,
@@ -1913,6 +1990,9 @@ namespace MobileGL::MG_Impl::GLImpl {
             : GetNamedFramebufferObject_State(framebuffer, "NamedFramebufferDrawBuffers_State");
         if (!framebufferObject) return;
         DrawBuffersForFramebuffer_State(framebufferObject, framebuffer == 0, n, bufs, false);
+#if MOBILEGL_PIPE_PUSH
+        PipePublishFramebufferByName(framebufferObject);
+#endif
     }
 
     void NamedFramebufferDrawBuffer_State(GLuint framebuffer, GLenum buf) {
@@ -1927,6 +2007,9 @@ namespace MobileGL::MG_Impl::GLImpl {
             const GLenum bufs[] = {buf};
             DrawBuffersForFramebuffer_State(framebufferObject, framebuffer == 0, 1, bufs, true);
         }
+#if MOBILEGL_PIPE_PUSH
+        PipePublishFramebufferByName(framebufferObject);
+#endif
     }
 
     void NamedFramebufferReadBuffer_State(GLuint framebuffer, GLenum src) {
@@ -1936,6 +2019,9 @@ namespace MobileGL::MG_Impl::GLImpl {
         if (!framebufferObject) return;
         ReadBufferForFramebuffer_State(framebufferObject, framebuffer == 0, src,
                                        "NamedFramebufferReadBuffer_State");
+#if MOBILEGL_PIPE_PUSH
+        PipePublishFramebufferByName(framebufferObject);
+#endif
     }
 
     SharedPtr<MG_State::GLState::FramebufferObject> GetFramebufferObjectForNamedClear(GLuint framebuffer,

MobileGL/MG_Impl/GLImpl/Texture/GL_Texture.cpp

@@ -31,6 +31,9 @@
 #include <MG_Util/Math/FixedPointConversion.h>
 #include <MG_State/GLState/TextureState/TextureObjectBuffer.h>
 #include <MG_Impl/Pipe/PipeFill.h>
+// P4a, ID-18 M2. The ONE door MG_State and MG_Impl have into the client's emitters; the three
+// call sites below are declarations only, exactly as the frontend's mutators are.
+#include <MG_Pipe/PipeMutation.h>
 
 namespace MobileGL::MG_Impl::GLImpl {
     static SharedPtr<MG_State::GLState::ITextureObject> nullTextureObject;
@@ -1337,6 +1340,30 @@ namespace MobileGL::MG_Impl::GLImpl {
                     std::format("pname {} is not a valid texture parameter.", MG_Util::ConvertGLEnumToString(pname))));
             return;
         }
+#if MOBILEGL_PIPE_PUSH
+        // P4a, ID-18 M2 - THE THIRTEENTH MGP_NOTE_AGGREGATE(TextureParams) SITE, and the one
+        // no publisher reached. Nine of the thirteen are TextureObject.cpp's own mutators and
+        // publish through TextureObjectBase::PipePublishParams; the tenth is
+        // SetDepthStencilTextureMode; two more move fields MGPTextureParams does not carry. The
+        // last is SamplerObject::BumpVersion, whose own comment calls it "the one choke point
+        // every setter reaches" - and MGPTextureParams takes MinLod, MaxLod and LodBias off that
+        // object, so every glTexParameter that writes GL_TEXTURE_MIN_LOD / MAX_LOD / LOD_BIAS
+        // landed on state nothing watched and the applier's record kept saying MinLod = 0.
+        // Wrong pixels, not a lost optimisation.
+        //
+        // THE HOOK IS HERE RATHER THAN ON BumpVersion because MG_State/GLState/SamplerState is
+        // package C's after the tag; C.7 grants this file for exactly this class of path ("the
+        // grant is one call site per path"), and this switch IS the path - every arm of it
+        // either writes the built-in SamplerObject or writes a texture field that publishes for
+        // itself. Placed after the switch, so the error arms above return without emitting.
+        //
+        // IT IS ALSO ID-14's RE-EMIT HOOK. C's sampler CSO cache is content-addressed, so the
+        // handle MGPTextureParams::BuiltinSampler names MOVES WITH THE CONTENT; the emitter
+        // re-Acquires from the cache and releases the previous handle here. An over-call is
+        // free: the emitter's version-first skip reads GetTextureParamsVersion() AND
+        // SamplerObject::GetVersion() and returns without hashing anything when neither moved.
+        MobileGL::MG_Pipe::MGPipeEmitTextureParams(*textureObject);
+#endif
     }
 
     void TextureParameterObjectf_State(const SharedPtr<MG_State::GLState::ITextureObject>& textureObject, GLenum pname,
@@ -1415,6 +1442,30 @@ namespace MobileGL::MG_Impl::GLImpl {
                     std::format("pname {} is not a valid texture parameter.", MG_Util::ConvertGLEnumToString(pname))));
             return;
         }
+#if MOBILEGL_PIPE_PUSH
+        // P4a, ID-18 M2 - THE THIRTEENTH MGP_NOTE_AGGREGATE(TextureParams) SITE, and the one
+        // no publisher reached. Nine of the thirteen are TextureObject.cpp's own mutators and
+        // publish through TextureObjectBase::PipePublishParams; the tenth is
+        // SetDepthStencilTextureMode; two more move fields MGPTextureParams does not carry. The
+        // last is SamplerObject::BumpVersion, whose own comment calls it "the one choke point
+        // every setter reaches" - and MGPTextureParams takes MinLod, MaxLod and LodBias off that
+        // object, so every glTexParameter that writes GL_TEXTURE_MIN_LOD / MAX_LOD / LOD_BIAS
+        // landed on state nothing watched and the applier's record kept saying MinLod = 0.
+        // Wrong pixels, not a lost optimisation.
+        //
+        // THE HOOK IS HERE RATHER THAN ON BumpVersion because MG_State/GLState/SamplerState is
+        // package C's after the tag; C.7 grants this file for exactly this class of path ("the
+        // grant is one call site per path"), and this switch IS the path - every arm of it
+        // either writes the built-in SamplerObject or writes a texture field that publishes for
+        // itself. Placed after the switch, so the error arms above return without emitting.
+        //
+        // IT IS ALSO ID-14's RE-EMIT HOOK. C's sampler CSO cache is content-addressed, so the
+        // handle MGPTextureParams::BuiltinSampler names MOVES WITH THE CONTENT; the emitter
+        // re-Acquires from the cache and releases the previous handle here. An over-call is
+        // free: the emitter's version-first skip reads GetTextureParamsVersion() AND
+        // SamplerObject::GetVersion() and returns without hashing anything when neither moved.
+        MobileGL::MG_Pipe::MGPipeEmitTextureParams(*textureObject);
+#endif
     }
 
     void GetTextureParameterObjectiv_State(const SharedPtr<MG_State::GLState::ITextureObject>& textureObject,
@@ -2105,6 +2156,30 @@ namespace MobileGL::MG_Impl::GLImpl {
                     std::format("pname {} is not a valid texture parameter.", MG_Util::ConvertGLEnumToString(pname))));
             return;
         }
+#if MOBILEGL_PIPE_PUSH
+        // P4a, ID-18 M2 - THE THIRTEENTH MGP_NOTE_AGGREGATE(TextureParams) SITE, and the one
+        // no publisher reached. Nine of the thirteen are TextureObject.cpp's own mutators and
+        // publish through TextureObjectBase::PipePublishParams; the tenth is
+        // SetDepthStencilTextureMode; two more move fields MGPTextureParams does not carry. The
+        // last is SamplerObject::BumpVersion, whose own comment calls it "the one choke point
+        // every setter reaches" - and MGPTextureParams takes MinLod, MaxLod and LodBias off that
+        // object, so every glTexParameter that writes GL_TEXTURE_MIN_LOD / MAX_LOD / LOD_BIAS
+        // landed on state nothing watched and the applier's record kept saying MinLod = 0.
+        // Wrong pixels, not a lost optimisation.
+        //
+        // THE HOOK IS HERE RATHER THAN ON BumpVersion because MG_State/GLState/SamplerState is
+        // package C's after the tag; C.7 grants this file for exactly this class of path ("the
+        // grant is one call site per path"), and this switch IS the path - every arm of it
+        // either writes the built-in SamplerObject or writes a texture field that publishes for
+        // itself. Placed after the switch, so the error arms above return without emitting.
+        //
+        // IT IS ALSO ID-14's RE-EMIT HOOK. C's sampler CSO cache is content-addressed, so the
+        // handle MGPTextureParams::BuiltinSampler names MOVES WITH THE CONTENT; the emitter
+        // re-Acquires from the cache and releases the previous handle here. An over-call is
+        // free: the emitter's version-first skip reads GetTextureParamsVersion() AND
+        // SamplerObject::GetVersion() and returns without hashing anything when neither moved.
+        MobileGL::MG_Pipe::MGPipeEmitTextureParams(*textureObject);
+#endif
     }
 
     void TexParameteri_State(GLenum target, GLenum pname, GLint param) {

MobileGL/MG_Impl/Pipe/CompositeResolver.h

@@ -0,0 +1,270 @@
+// MobileGL - MobileGL/MG_Impl/Pipe/CompositeResolver.h
+// Copyright (c) 2025-2026 MobileGL-Dev
+// Licensed under the GNU Lesser General Public License v3.0:
+//   https://www.gnu.org/licenses/gpl-3.0.txt
+//   https://www.gnu.org/licenses/lgpl-3.0.txt
+// SPDX-License-Identifier: LGPL-3.0-only
+// End of Source File Header
+
+#pragma once
+#include <Includes.h>
+
+// P4a's PROGRAM-PIPELINE COMPOSITE, on the client side.
+//
+// GLContext::GetProgramForDraw() already flattens a bound pipeline into one hidden composite
+// ProgramObject entirely in the frontend - it joins every graphics stage, computes the
+// pipeline's draw-program signature, looks it up in the pipeline's own cache and, on a miss,
+// attaches each stage's LINKED SNAPSHOT into a fresh ProgramObject and links it. All of that
+// is frontend work and none of it moves. What this file adds is the one thing the wire needs:
+// the composite gets ONE handle, out of the ShaderCso reserved high band, and
+// create_shader_state goes out for it exactly as for an ordinary program. THE SERVER NEVER
+// LEARNS IT IS A COMPOSITE and needs no "resolved draw program" hook at all.
+//
+// WHY A BAND RATHER THAN A FLAG ON THE HANDLE: a flag would have to be carried, honoured and
+// masked off by every consumer of a ShaderCso handle, on both sides; a reserved slot range is
+// a property of the allocator instead, so "an ordinary program can never be handed a composite
+// slot" is true by construction. MGPipeSlotAllocator::Allocate refuses the band outright and
+// AllocateComposite is the only door in.
+//
+// WHAT THIS FILE IS ACTUALLY FOR: the composite's slot has TWO INDEPENDENT RELEASE PATHS and
+// either order has to free it exactly once.
+//   * the pipeline cache drops the composite when the draw-program signature moves. In the
+//     frontend that overwrite drops the last SharedPtr, so the composite's own destructor
+//     usually runs first; the resolver still speaks the release, because "usually" is not a
+//     contract and a client that only reacted to destructors would leak a slot the moment the
+//     frontend started holding a second reference.
+//   * the composite ProgramObject's own ~ProgramObject, which is an ordinary program's death
+//     path and takes the same helper.
+// Both go through MGPipeEmitShaderCsoDestroyAndFree, and whichever runs second is a PROVEN
+// no-op: MGPipeSlotAllocator::Free refuses a slot that is not live at that generation and
+// bumps no generation of its own, so a double release cannot skip a generation either.
+//
+// THE MEMO's KEY IS (CONTEXT ID, PIPELINE GL NAME) AND THE CONTEXT HALF IS NOT OPTIONAL.
+// This resolver is a PROCESS singleton while a pipeline's GL name is per context: GLContext
+// owns m_programPipelines AND its own name generator m_programPipelineNames (Core.h), so name
+// N names two different ProgramPipelineObjects in two contexts, each with its own composite
+// and its own handle. Keyed on the name alone, the first emission after a make-current found
+// the OTHER context's entry, matched nothing - two composites are two ProgramObjects with two
+// lifetime ids, so the handles differ even when the stage set and the signature are identical
+// - and released it: a delete_shader_state and a cleared publication latch for a composite
+// whose frontend ProgramObject is alive, its band slot handed back and re-issued at gen + 1,
+// and the server rebuilding that program (glslang + SPIR-V + spirv-opt, the very cost the
+// signature below exists to avoid) once per context switch.
+//
+// THE CONTEXT ID IS GLContext::GetTextureContextId() AND NOTHING ELSE - the tree's existing
+// never-reused per-context id (TextureState::AllocateContextId; PipeInputs carries it as
+// m_textureContextId at seven fill points and the backends' own per-context memos key on it).
+// Deliberately NOT the GLContext ADDRESS that MGB_CTX_IDENTITY and MGPipeTracker::m_context
+// compare, because Core.h states the reason that id exists at all: a context freed and remade
+// lands on the old heap address, which would put this same defect back one context recreation
+// later.
+//
+// WHAT RELEASES A DESTROYED CONTEXT's ENTRIES: nothing in this file, and that is the correct
+// answer rather than an omission. Destroying a context drops m_programPipelines, which drops
+// each ProgramPipelineObject, which drops the composite it cached; ~ProgramObject then runs
+// MGPipeEmitShaderCsoDestroyAndFree - the composite's OWN release path, the second of the two
+// above - and the slot goes back exactly once. The entries those composites leave behind can
+// never be found again (no future Observe can carry a dead context id) and could not release
+// anything if they were (the allocator erases the lifetime-id mapping on Free), so Reset()
+// DROPS them instead of releasing them. That is also what bounds the vector; see Reset().
+//
+// THE SIGNATURE IS ComputeDrawProgramSignature(), the per-graphics-stage {lifetimeId,
+// GetLinkVersion()} array - and DELIBERATELY NOT GetBackendStateVersion(), which is what made
+// the SSO conformance loop rebuild the composite (glslang + SPIR-V + spirv-opt) on every draw,
+// because a glUniform1i to a sampler moves it.
+//
+// HEADER-ONLY, for the ownership reason Tracker.h states: a new .cpp would need the root
+// CMakeLists.txt, which is the contract package's.
+//
+// IT IS INCLUDED BY ProgramEmit.h AND NOT THE OTHER WAY ROUND, deliberately: the composite is
+// a special case of the program family's own emission, so the family header depends on this
+// one and this one depends on nothing of the family's. The reverse arrangement would make the
+// resolver reachable only from a translation unit that had already decided to use it, i.e.
+// dead in the build that matters and live only in the tests.
+#if MOBILEGL_PIPE_PUSH
+#include <MG_Impl/Pipe/SlotAllocator.h>
+#include <MG_Pipe/MGPipe.h>
+#include <MG_Pipe/PipeMutation.h>
+#include <MG_State/GLState/ProgramState/ProgramObject.h>
+#include <MG_State/GLState/ProgramState/ProgramPipelineObject.h>
+
+namespace MobileGL::MG_Pipe {
+
+    // IS THIS PROGRAM A PIPELINE COMPOSITE? A composite is the one ProgramObject in the system
+    // constructed with external index 0 (Core.cpp's MakeShared<ProgramObject>(0u)), and that is
+    // not an accident of implementation: it is deliberately not a named program, so it must not
+    // answer glIsProgram and must not consume a GL name, and glCreateProgram never returns 0.
+    //
+    // ASKED THIS WAY RATHER THAN CARRIED ON THE OBJECT because a Bool member on ProgramObject
+    // would resize the pull build's object and break G1 outright - the phase's admitted-resize
+    // set is empty - and a hook in Core.cpp would have to be maintained on a path that already
+    // states the invariant in its own comment.
+    inline Bool MGPipeProgramIsPipelineComposite(const MG_State::GLState::ProgramObject& program) {
+        return program.GetExternalIndex() == 0;
+    }
+
+    class MGPipeCompositeResolver {
+    public:
+        using ProgramObject = MG_State::GLState::ProgramObject;
+        using ProgramPipelineObject = MG_State::GLState::ProgramPipelineObject;
+        using DrawProgramSignature = ProgramPipelineObject::DrawProgramSignature;
+
+        struct Counters {
+            Uint64 Mints = 0;    // signatures this resolver has seen minted
+            Uint64 Reuses = 0;   // a signature that had not moved
+            Uint64 Releases = 0; // signature-move releases, i.e. the pipeline-cache path
+            // Entries dropped by Reset() because the composite's slot was already gone - the
+            // shape every entry of a DESTROYED CONTEXT ends in. A dropped entry is not a
+            // release: nothing is emitted and nothing is freed, the obligation having been
+            // discharged by the composite's own ~ProgramObject.
+            Uint64 Sweeps = 0;
+        };
+
+        // Told, at every emission, which composite the frontend handed out for which pipeline.
+        // Returns the handle the emitter should use, which is always the one already minted off
+        // the composite's own lifetime id - the resolver never mints a second identity for an
+        // object that has one.
+        //
+        // WHEN THE SIGNATURE MOVES the previous composite's slot is released here, through the
+        // one death helper and in its fixed order. That is the pipeline-cache release path; the
+        // composite's own destructor is the other one and the second of the two is the proven
+        // no-op.
+        MGPipeHandle Observe(Uint64 contextId, const ProgramPipelineObject& pipeline,
+                             const ProgramObject& composite, MGPipeHandle handle) {
+            const DrawProgramSignature signature = pipeline.ComputeDrawProgramSignature();
+            const Uint pipelineName = pipeline.GetExternalIndex();
+            Entry* entry = Find(contextId, pipelineName);
+            if (entry != nullptr) {
+                if (entry->Signature == signature && entry->Handle == handle) {
+                    // THE SAME COMPOSITE. Not merely "the same signature": the handle is minted
+                    // off the composite ProgramObject's own lifetime id, so an identical handle
+                    // IS an identical object and there is nothing to release. Live is
+                    // deliberately NOT touched - it is the release obligation and it is still
+                    // owed for exactly this handle.
+                    ++m_counters.Reuses;
+                    return handle;
+                }
+                // A MOVED SIGNATURE ON THIS CONTEXT's OWN ENTRY, which is the only thing that
+                // can reach here now: another context's pipeline of the same name is not found
+                // above and therefore not released, its obligation staying owed to the context
+                // that took it.
+                ReleaseEntry(*entry);
+            } else {
+                m_entries.push_back(Entry{});
+                entry = &m_entries.back();
+                entry->ContextId = contextId;
+                entry->PipelineName = pipelineName;
+            }
+            entry->Signature = signature;
+            entry->Handle = handle;
+            entry->CompositeLifetimeId = composite.GetLifetimeId();
+            entry->Live = true;
+            ++m_counters.Mints;
+            return handle;
+        }
+
+        // A make-current, and it RELEASES NOTHING. The entries name composites that belong to
+        // the frontend objects of the context being left, those objects outlive the switch, and
+        // releasing them would emit a delete for a live program.
+        //
+        // NOR IS ANY MEMO INVALIDATED, and that is what the context key bought. This used to
+        // clear a per-entry `Fresh` flag beside `Live`, because with a name-only key an entry
+        // could not say whether it described "my own pipeline before the switch" or "another
+        // context's pipeline of the same name" - and exactly one of those two properties could
+        // hold at a time. The key answers the question directly now, so the freshness flag and
+        // its one reader (a HandleFor() accessor that had no caller anywhere in the tree) are
+        // both gone rather than left as scaffolding: `Live`, the release obligation, is the
+        // entry's only state and nothing but ReleaseEntry may clear it.
+        //
+        // WHAT IS LEFT TO DO HERE IS RECLAMATION, and this is the one moment the client is told
+        // that a context boundary was crossed. An entry whose composite slot is no longer live
+        // has had its obligation discharged elsewhere - by that composite's own ~ProgramObject,
+        // which is precisely what happened to EVERY entry of a context that has just been
+        // destroyed - so it is DROPPED rather than released: a release would resolve nothing
+        // anyway (the allocator erases the lifetime-id mapping on Free) and no reader is left.
+        // Without this the vector would grow by one per (context, pipeline name) pair the
+        // process ever used, where the name-only key bounded it by the highest pipeline name;
+        // with it, it is bounded by the pairs whose composite slot is actually live.
+        void Reset() {
+            SizeT kept = 0;
+            for (SizeT i = 0; i < m_entries.size(); ++i) {
+                if (!m_entries[i].Live || !MGPipeSlots().IsLive(MGPipeKind::ShaderCso, m_entries[i].Handle)) {
+                    ++m_counters.Sweeps;
+                    continue;
+                }
+                if (kept != i) m_entries[kept] = m_entries[i];
+                ++kept;
+            }
+            m_entries.resize(kept);
+        }
+
+        void ResetCounters() { m_counters = Counters{}; }
+
+        // Diagnostics and unit cases only; nothing on the emission path asks. There is no
+        // HandleFor(name) accessor and there must not be one: the emitter takes the handle from
+        // the composite ProgramObject it already holds, so a lookup by name would be a second
+        // authority on an identity the allocator already owns.
+        SizeT Size() const { return m_entries.size(); }
+        const Counters& GetCounters() const { return m_counters; }
+
+    private:
+        struct Entry {
+            // NO FRONTEND SharedPtr, and that is the exit-order rule rather than a style
+            // choice: a static that held one would put a frontend destructor on an exit
+            // handler's path into a torn-down pipe. A GL name, a signature of plain integers,
+            // a handle and a lifetime id are all this needs.
+            // KEYED ON (CONTEXT ID, GL NAME), and the name half is the GL name because a
+            // ProgramPipelineObject has no lifetime id - ComputeDrawProgramSignature reads the
+            // STAGE programs' ids and the pipeline itself carries none. The context half is
+            // GLContext::GetTextureContextId(); see the file header for why the name alone was
+            // wrong and why the context ADDRESS would be too.
+            //
+            // WITHIN ONE CONTEXT glGenProgramPipelines recycles names, so a deleted-and-
+            // recreated pipeline can still inherit its predecessor's entry; that is bounded and
+            // self-correcting rather than a hazard. The first Observe on the new object finds a
+            // signature and a handle that do not match and releases the old entry, and that
+            // release resolves NOTHING - the allocator erases the lifetime-id mapping on Free,
+            // so a stale CompositeLifetimeId emits no delete and frees no slot; all it costs is
+            // one redundant, idempotent death notice, which is the same shape the composite's
+            // own second release path already has.
+            Uint64 ContextId = 0;
+            Uint PipelineName = 0;
+            DrawProgramSignature Signature{};
+            MGPipeHandle Handle = kMGPipeNullHandle;
+            Uint64 CompositeLifetimeId = 0;
+            // THE RELEASE OBLIGATION. Set when this entry takes responsibility for a composite's
+            // slot, cleared ONLY by ReleaseEntry when that responsibility is discharged.
+            Bool Live = false;
+        };
+
+        // BOTH HALVES OF THE KEY, always. An entry of another context is not this pipeline's
+        // entry: not found, not matched, not released.
+        Entry* Find(Uint64 contextId, Uint pipelineName) {
+            for (Entry& entry : m_entries) {
+                if (entry.ContextId == contextId && entry.PipelineName == pipelineName) return &entry;
+            }
+            return nullptr;
+        }
+
+        void ReleaseEntry(Entry& entry) {
+            if (!entry.Live || entry.CompositeLifetimeId == 0) return;
+            entry.Live = false;
+            MGPipeEmitShaderCsoDestroyAndFree(entry.CompositeLifetimeId);
+            entry.Handle = kMGPipeNullHandle;
+            entry.CompositeLifetimeId = 0;
+            ++m_counters.Releases;
+        }
+
+        Vector<Entry> m_entries;
+        Counters m_counters;
+    };
+
+    inline MGPipeCompositeResolver& MGPipeCompositeResolverInstance() {
+        // NEVER DESTROYED, for MGPipeTrackerInstance()' reason, and named in the phase's risk
+        // list beside the other three new client singletons: heap-constructed and intentionally
+        // leaked at exit, holding no frontend SharedPtr.
+        static MGPipeCompositeResolver* resolver = new MGPipeCompositeResolver();
+        return *resolver;
+    }
+} // namespace MobileGL::MG_Pipe
+#endif // MOBILEGL_PIPE_PUSH

MobileGL/MG_Impl/Pipe/FramebufferEmit.h

@@ -26,36 +26,606 @@
 // CMakeLists.txt that would name a new .cpp is the contract package's and is frozen behind the
 // tag. MG_Impl/Pipe/PipeFill.cpp is the one translation unit that includes it in the library.
 #if MOBILEGL_PIPE_PUSH
+#include <MG_Impl/Pipe/SetHashSuppressor.h>
+#include <MG_Impl/Pipe/SlotAllocator.h>
+#include <MG_Impl/Pipe/TextureEmit.h>
+#include <MG_Impl/Pipe/Tracker.h>
 #include <MG_Pipe/MGPipe.h>
 #include <MG_Pipe/PipeApply.h>
 #include <MG_State/GLState/Core.h>
+#include <MG_Util/Metrics/PipeStats.h>
+
+#include <xxhash.h>
+
+#include <algorithm>
 
 namespace MobileGL::MG_Pipe {
 
-    // WHICH SUBSYSTEM BIT THIS BUILD ACTUALLY EMITS FOR, and it is 0 until the emitter below
-    // has a body. PipeFill.cpp ORs the four per-family constants into kMGPipeWiredSubsystems,
-    // so the bit is added by the commit that gives the emitters their bodies, with no file
-    // touched twice - and a Coverage.def row can never silently drop a field on the floor
-    // before the call that carries it exists.
-    inline constexpr Uint64 kMGPipeWiredFramebufferSubsystem = 0;
+    // WHICH SUBSYSTEM BIT THIS BUILD ACTUALLY EMITS FOR. PipeFill.cpp ORs the four per-family
+    // constants into kMGPipeWiredSubsystems, so the bit is added by the commit that gives the
+    // emitters their bodies, with no file touched twice - and a Coverage.def row can never
+    // silently drop a field on the floor before the call that carries it exists.
+    //
+    // TURNING IT ON RETIRES NO PULL. GetFramebufferBindingSlot is the family's one
+    // Coverage.def emitted row and PipeFill.cpp's EmittedCallSuppliesTheWholeField answers
+    // FALSE for it, with the reason: the field's storage is a BindingSlot<FramebufferObject> -
+    // a frontend heap reference - and the call that supplies it carries eight-byte {slot, gen}
+    // handles and a fully resolved descriptor. So this bit switches the EMISSION on and the
+    // residual fill keeps writing the mirror, which is what keeps the verify lane at zero
+    // divergence.
+    inline constexpr Uint64 kMGPipeWiredFramebufferSubsystem = kMGPipeSubsystemFramebuffer;
+
+    inline Bool MGPipeFramebufferSubsystemEnabled() {
+        return (kMGPipeWiredFramebufferSubsystem & kMGPipeSubsystemFramebuffer) != 0 &&
+               (MG_Config::Features.PipePush & kMGPipeSubsystemFramebuffer) != 0;
+    }
+
+    // ---------------------------------------------------------------------------------
+    // D-C1: the MGPSurface builder, one pure function, one statement per field
+    // ---------------------------------------------------------------------------------
+
+    // MGPSurface::Kind's three constants ARE THE CONTRACT'S (ID-12 DV-4, c0c):
+    // kMGPipeSurfaceKindNone / ...Texture / ...Renderbuffer live in MG_Pipe/MGPipeTypes.h under
+    // exactly these names with the same MGPipeKind derivation and the same static_assert. This
+    // package's copies were a redefinition in the same namespace and are deleted.
+
+    // The upload target an attachment names, RESOLVED: an attachment made through an entry
+    // point that carries no face token stores TextureUploadTarget::Unknown, and the record goes
+    // out fully resolved - nothing in it may require a lookup on the far side.
+    //
+    // THE FALLBACK IS ONLY LEGAL FOR A SINGLE-TARGET TEXTURE (m1), and v1's was not. The
+    // precedent it copied - FramebufferAttachmentObject::GetSize - needs an EXTENT, which is
+    // identical across a cube map's six faces; face IDENTITY is not, so
+    // `glFramebufferTexture(GL_COLOR_ATTACHMENT0, cube, 0)` resolved to targets[0] and the
+    // record ASSERTED CubeMapPositiveX for a layered attachment that names all six. A texture
+    // with exactly one upload target has a [0] that IS the truth; anything else keeps Unknown,
+    // which is the value the field already carries for "this attachment names no single face"
+    // and which Layered = 1 tells the reader to ignore.
+    inline MobileGL::TextureUploadTarget MGPipeResolveAttachmentUploadTarget(
+        const MG_State::GLState::FramebufferAttachmentObject& attachment) {
+        MobileGL::TextureUploadTarget resolved = attachment.GetTextureUploadTarget();
+        if (resolved != MobileGL::TextureUploadTarget::Unknown) return resolved;
+        const auto& texture = attachment.GetTexture();
+        if (!texture) return MobileGL::TextureUploadTarget::Unknown;
+        const auto& targets = texture->GetUploadTargets();
+        return targets.size() == 1 ? targets[0] : MobileGL::TextureUploadTarget::Unknown;
+    }
+
+    // ONE PURE FUNCTION, ONE STATEMENT PER FIELD, and that shape is a gate requirement rather
+    // than taste: G7's scripted control stops this conversion copying exactly one member
+    // (MGPSurface::Layered) and expects the framebuffer suite to go red NAMING that field. A
+    // loop or a memcpy would make the control unanswerable.
+    //
+    // `res` is handed in because resolving it needs the slot allocator and this function stays
+    // pure; `internalFormat` is INLINE in the record on purpose, so the four cross-object masks
+    // fall out at push time with no lookup on the far side.
+    // THE EMPTY POINT IS THE ZERO-INITIALISED RECORD EXCEPT FOR ITS TWO TARGET FIELDS. Both
+    // are Uint16 enumerations whose zero is a REAL value - TextureTarget::Texture1D and
+    // TextureUploadTarget::Texture1D - so a reader that forgot to gate on Kind would read a
+    // plausible wrong answer rather than a nonsense one. Unknown (0xFFFF) is what the contract
+    // spells for TextureTarget (kMGPipeSurfaceNoTextureTarget) and m6 applies the same rule to
+    // UploadTarget, which shares the collision ID-12 DV-3 ruled on for MGPSubData::Target.
+    inline MGPSurface MGPipeEmptySurface() {
+        MGPSurface surface{};
+        surface.UploadTarget = static_cast<Uint16>(MobileGL::TextureUploadTarget::Unknown);
+        surface.TextureTarget = kMGPipeSurfaceNoTextureTarget;
+        return surface;
+    }
+
+    inline MGPSurface MGPipeBuildSurface(const MG_State::GLState::FramebufferAttachmentObject& attachment,
+                                         MGPipeHandle res) {
+        MGPSurface surface = MGPipeEmptySurface();
+        if (attachment.IsEmpty()) return surface;
+        surface.Res = res;
+        if (attachment.IsTexture()) {
+            const auto& texture = attachment.GetTexture();
+            surface.Kind = kMGPipeSurfaceKindTexture;
+            surface.InternalFormat = static_cast<Uint32>(texture->GetFormat());
+            surface.Layered = attachment.IsLayered() ? 1 : 0;
+            surface.Level = static_cast<Uint16>(std::max<Int>(attachment.GetTextureLevel(), 0));
+            surface.Layer = static_cast<Uint32>(std::max<Int>(attachment.GetTextureLayer(), 0));
+            surface.UploadTarget = static_cast<Uint16>(MGPipeResolveAttachmentUploadTarget(attachment));
+            // ID-12 DV-5: the field that WAS Pad0, and the size did not move. The four
+            // cross-object masks all reduce to (format, TEXTURE TARGET) -
+            // ShouldUseCaveatTextureFormat / BackendTextureFormatAddsAlpha - and no
+            // TextureUploadTarget -> TextureTarget inverse exists anywhere in the tree, so
+            // without this the inline InternalFormat cannot make them fall out at push time and
+            // the backend keeps reading the frontend attachment objects.
+            surface.TextureTarget = static_cast<Uint16>(texture->GetTarget());
+            return surface;
+        }
+        const auto& renderbuffer = attachment.GetRenderbuffer();
+        surface.Kind = kMGPipeSurfaceKindRenderbuffer;
+        surface.InternalFormat = static_cast<Uint32>(renderbuffer->GetInternalFormat());
+        surface.Layered = 0;
+        surface.Level = 0;
+        surface.Layer = 0;
+        return surface;
+    }
+
+    // MGPFramebufferState::DrawBuffers[i]: an index INTO THIS RECORD'S OWN Color[] array, and
+    // -1 for NONE, which is the field's documented convention read literally.
+    //
+    // THE FOUR DEFAULT-FRAMEBUFFER TOKENS map to 0, and that is a deliberate narrowing rather
+    // than an oversight: a default framebuffer has one colour surface, this record carries it
+    // in Color[0] (see MGPipeBuildFramebufferState), and IsDefault is what tells the server
+    // which framebuffer it is looking at. The distinction the narrowing loses is FRONT versus
+    // BACK and LEFT versus RIGHT, which MobileGL's frontend never gives a default framebuffer
+    // in the first place - FramebufferObject's constructor seeds BackLeft and nothing writes
+    // another. A phase that needs stereo has to widen the field, not re-encode this one.
+    inline Int8 MGPipeDrawBufferIndex(MobileGL::FramebufferAttachmentType buffer) {
+        using MobileGL::FramebufferAttachmentType;
+        if (buffer == FramebufferAttachmentType::None) return -1;
+        if (buffer >= FramebufferAttachmentType::Color0 && buffer <= FramebufferAttachmentType::ColorMax) {
+            return static_cast<Int8>(static_cast<Int>(buffer) - static_cast<Int>(FramebufferAttachmentType::Color0));
+        }
+        return 0;
+    }
+
+    // m2: A DRAW-BUFFER TOKEN CAN NAME A COLOUR POINT THE RECORD CANNOT CARRY, and D-C3's
+    // refusal loop only ever scanned ATTACHMENTS. `glDrawBuffers(1, {GL_COLOR_ATTACHMENT10})`
+    // with nothing attached at 10 is legal state - draw-incomplete, but legal - and the index
+    // above would have written 10 into a record whose Color[] is 8 wide, so the server would
+    // index out of its own storage or invent a bound the record does not carry. Truncating
+    // silently is the bug class this phase is closing, so the record is refused exactly as an
+    // over-wide attachment is.
+    inline Bool MGPipeDrawBufferIsInsideTheWireWidth(MobileGL::FramebufferAttachmentType buffer) {
+        using MobileGL::FramebufferAttachmentType;
+        if (buffer < FramebufferAttachmentType::Color0 || buffer > FramebufferAttachmentType::ColorMax) {
+            return true; // None and the four default-framebuffer tokens; neither indexes Color[]
+        }
+        return static_cast<Int>(buffer) - static_cast<Int>(FramebufferAttachmentType::Color0) <
+               static_cast<Int>(kMGPipeMaxColorAttachments);
+    }
+
+    // ---------------------------------------------------------------------------------
+    // D-C4: ContentHash, and the one input it must not swallow
+    // ---------------------------------------------------------------------------------
+    //
+    // XXH64 over the WHOLE record with ContentHash itself zeroed, computed field-wise into a
+    // zero-initialised staging copy so that no padding byte can enter the hash. Two jobs: the
+    // server's render-pass memo key, and this client's emission suppressor.
+    //
+    // IT MUST COVER Fbo. A recycled framebuffer handle whose successor happens to carry an
+    // identical attachment set would otherwise be suppressed against its predecessor; Fbo
+    // carries Gen, so it cannot be.
+    //
+    // IT MUST COVER DrawBuffers[8], and this is the trap worth naming. The backend derives the
+    // fragColor BROADCAST COUNT from the draw-buffer array, and it does that at the verb, from
+    // the framebuffer state it then holds, precisely so a program can relink inside the same
+    // draw. A hash that did not cover the array would let a suppressed set_framebuffer_state
+    // mean "the draw buffers did not move" when they had, and the shader would be specialised
+    // for the previous output shape. With the array in the hash, a suppression provably means
+    // the array did not move, which provably means the broadcast count did not move.
+    inline void MGPipeCopySurfaceForHash(MGPSurface& dst, const MGPSurface& src) {
+        dst.Res = src.Res;
+        dst.InternalFormat = src.InternalFormat;
+        dst.Kind = src.Kind;
+        dst.Layered = src.Layered;
+        dst.Level = src.Level;
+        dst.Layer = src.Layer;
+        dst.UploadTarget = src.UploadTarget;
+        // MANDATORY, not optional: TextureTarget is a PipeFields.def row now, so a
+        // field-wise copy that skipped it would suppress a record whose only moved field is
+        // the attachment's texture target - and that field decides three of the four
+        // cross-object masks.
+        dst.TextureTarget = src.TextureTarget;
+    }
+
+    inline Uint64 MGPipeFramebufferStateContentHash(const MGPFramebufferState& state) {
+        MGPFramebufferState staging{};
+        staging.Fbo = state.Fbo;
+        for (SizeT i = 0; i < kMGPipeMaxColorAttachments; ++i) {
+            MGPipeCopySurfaceForHash(staging.Color[i], state.Color[i]);
+        }
+        MGPipeCopySurfaceForHash(staging.Depth, state.Depth);
+        MGPipeCopySurfaceForHash(staging.Stencil, state.Stencil);
+        MGPipeCopySurfaceForHash(staging.ReadSurface, state.ReadSurface);
+        for (SizeT i = 0; i < kMGPipeMaxColorAttachments; ++i) {
+            staging.DrawBuffers[i] = state.DrawBuffers[i];
+        }
+        staging.Width = state.Width;
+        staging.Height = state.Height;
+        staging.Layers = state.Layers;
+        staging.Samples = state.Samples;
+        staging.FixedSampleLocations = state.FixedSampleLocations;
+        staging.IsDefault = state.IsDefault;
+        staging.Complete = state.Complete;
+        staging.Target = state.Target;
+        // staging.ContentHash stays 0 - that is the whole point.
+        return XXH64(&staging, sizeof(staging), 0);
+    }
+
+    // ---------------------------------------------------------------------------------
+    // The emitter
+    // ---------------------------------------------------------------------------------
 
-    // set_framebuffer_state. STUB AT THE CONTRACT COMMIT: it emits nothing and returns 0
-    // payload bytes, so the validate point's ladder has its final shape and the package that
-    // fills this in never edits PipeFill.cpp.
     class MGPipeFramebufferEmitter {
     public:
         using GLContext = MG_State::GLState::GLContext;
+        using FramebufferObject = MG_State::GLState::FramebufferObject;
+        using FramebufferAttachmentType = MobileGL::FramebufferAttachmentType;
+
+        // The handle for `fbo`. kMGPipeDefaultFramebuffer ({0,1}) for the default framebuffer,
+        // which is what retires the four pDefaultFramebufferInfo->defaultFBO identity
+        // comparisons into an ordinary handle compare; a client-minted {slot, gen} otherwise.
+        //
+        // Minted, never gated: a framebuffer handle is CLIENT state and costs one free-list pop.
+        static MGPipeHandle HandleFor(const FramebufferObject& fbo) {
+            if (fbo.IsDefaultFramebuffer()) return kMGPipeDefaultFramebuffer;
+            return MGPipeSlots().Acquire(MGPipeKind::Framebuffer, fbo.GetLifetimeId());
+        }
 
         // Returns the bytes that went on the wire, for the per-draw payload histogram.
         Uint64 EmitFramebufferState(GLContext& ctx) {
-            (void)ctx;
-            return 0;
+            if (!MGPipeFramebufferSubsystemEnabled()) return 0;
+            const auto& drawFbo = ctx.GetFramebufferBindingSlot(MobileGL::FramebufferTarget::Draw).GetBoundObject();
+            const auto& readFbo = ctx.GetFramebufferBindingSlot(MobileGL::FramebufferTarget::Read).GetBoundObject();
+            if (!drawFbo && !readFbo) return 0;
+
+            // ONE OBJECT BOUND TO BOTH TARGETS IS ONE RECORD WITH Target = Both, and that is
+            // not an optimisation: Espryt's "same FBO as draw" skip is the habitat of the
+            // read-buffer defect class, and a record that says which target it describes turns
+            // "apply the draw buffers only for the draw target" from call-site discipline into
+            // a one-line test on the far side.
+            const Bool shared = drawFbo && readFbo && drawFbo.get() == readFbo.get();
+
+            MGPFramebufferState drawState{};
+            MGPFramebufferState readState{};
+            Bool drawOk = false;
+            Bool readOk = false;
+            if (shared) {
+                drawOk = BuildFramebufferState(*drawFbo, MGPipeFramebufferTarget::Both, drawState);
+            } else {
+                if (drawFbo) {
+                    drawOk = BuildFramebufferState(*drawFbo, MGPipeFramebufferTarget::Draw, drawState);
+                }
+                if (readFbo) {
+                    readOk = BuildFramebufferState(*readFbo, MGPipeFramebufferTarget::Read, readState);
+                }
+            }
+            if (!drawOk && !readOk) return 0;
+
+            // THE SUPPRESSOR SLOT IS FED THE COMBINED ANSWER and the per-target latches decide
+            // which of the two records actually goes out. The slot exists so that
+            // InvalidateAll() on a fresh context reaches this family like every other, and so
+            // that "nothing moved" costs one compare rather than two.
+            const Uint64 drawHash = drawOk ? drawState.ContentHash : 0;
+            const Uint64 readHash = readOk ? readState.ContentHash : 0;
+            const Uint64 combined =
+                MGPipeMixShutter(MGPipeMixShutter(drawHash, readHash), shared ? 1u : 0u);
+            if (!MGPipeSetHashSuppressorInstance().ShouldEmit(MGPipeSuppressorSlot::SetFramebufferState,
+                                                             combined)) {
+                return 0;
+            }
+
+            Uint64 bytes = 0;
+            if (shared) {
+                if (drawOk && (drawHash != m_lastEmitted[kDraw] || drawHash != m_lastEmitted[kRead])) {
+                    bytes += Emit(drawState);
+                    m_lastEmitted[kDraw] = drawHash;
+                    m_lastEmitted[kRead] = drawHash;
+                }
+                return bytes;
+            }
+            if (drawOk && drawHash != m_lastEmitted[kDraw]) {
+                bytes += Emit(drawState);
+                m_lastEmitted[kDraw] = drawHash;
+            }
+            if (readOk && readHash != m_lastEmitted[kRead]) {
+                bytes += Emit(readState);
+                m_lastEmitted[kRead] = readHash;
+            }
+            return bytes;
         }
 
+        // ID-19(c): EVERY DSA ENTRY POINT THAT HANDS A FRAMEBUFFER TO THE SERVER BY NAME IS
+        // PRECEDED BY A RECORD FOR IT, and that is the phase's main correction rather than a
+        // nicety. With only the two BOUND-target records, glClearNamedFramebufferfv(fbo) on an
+        // unbound fbo made the backend mint a fresh driver framebuffer with NO ATTACHMENTS,
+        // find no record for it, decline, and issue the clear against it anyway -
+        // GL_INVALID_FRAMEBUFFER_OPERATION and nothing cleared, where the legacy arm cleared
+        // correctly (esprytobj C-1).
+        //
+        // THE TARGET IS Named ONLY WHEN THE OBJECT IS BOUND TO NEITHER BINDING. A record always
+        // writes FramebufferRecords[Fbo.Slot]; Draw/Read/Both ADDITIONALLY set the bound
+        // handle(s). So handing a currently-bound framebuffer a Named record would overwrite
+        // the bound record's Target with one that says "no binding" while BoundFramebuffer
+        // still names it, and the server would read a record whose Target contradicts the
+        // binding it is resolved through. Re-asserting the binding the object already has is
+        // free (the content hash suppresses it) and keeps the two consistent.
+        //
+        // Returns the bytes that went on the wire.
+        Uint64 EmitFramebufferByName(const FramebufferObject& fbo) {
+            if (!MGPipeFramebufferSubsystemEnabled()) return 0;
+            MGPipeFramebufferTarget target = MGPipeFramebufferTarget::Named;
+            const Bool boundToDraw = IsBoundTo(fbo, MobileGL::FramebufferTarget::Draw);
+            const Bool boundToRead = IsBoundTo(fbo, MobileGL::FramebufferTarget::Read);
+            if (boundToDraw && boundToRead) {
+                target = MGPipeFramebufferTarget::Both;
+            } else if (boundToDraw) {
+                target = MGPipeFramebufferTarget::Draw;
+            } else if (boundToRead) {
+                target = MGPipeFramebufferTarget::Read;
+            }
+
+            MGPFramebufferState state{};
+            if (!BuildFramebufferState(fbo, target, state)) return 0;
+
+            // THE SUPPRESSOR IS KEYED BY THE FRAMEBUFFER THE RECORD NAMES, never by one global
+            // slot (MGPipeTypes.h states the rule): two different objects' Named records in a
+            // row must both go out, and a Named record must never be suppressed against the
+            // same object's bound record or the reverse. Target is a ContentHash input, so the
+            // second half holds by construction; the per-object table is what buys the first.
+            // The two BOUND latches stay what they are - "does the server's draw/read binding
+            // already hold this record" - and a bound-target emission from here consults them,
+            // because a rebind of an unchanged object must still move the binding.
+            if (target == MGPipeFramebufferTarget::Named) {
+                NamedEntry& entry = NamedEntryFor(state.Fbo);
+                if (entry.Has && entry.Gen == state.Fbo.Gen && entry.LastHash == state.ContentHash) {
+                    return 0;
+                }
+                const Uint64 bytes = Emit(state);
+                entry.Has = true;
+                entry.Gen = state.Fbo.Gen;
+                entry.LastHash = state.ContentHash;
+                return bytes;
+            }
+            if (target == MGPipeFramebufferTarget::Both) {
+                if (state.ContentHash == m_lastEmitted[kDraw] && state.ContentHash == m_lastEmitted[kRead]) {
+                    return 0;
+                }
+                const Uint64 bytes = Emit(state);
+                m_lastEmitted[kDraw] = state.ContentHash;
+                m_lastEmitted[kRead] = state.ContentHash;
+                return bytes;
+            }
+            const SizeT slot = target == MGPipeFramebufferTarget::Read ? kRead : kDraw;
+            if (state.ContentHash == m_lastEmitted[slot]) return 0;
+            const Uint64 bytes = Emit(state);
+            m_lastEmitted[slot] = state.ContentHash;
+            return bytes;
+        }
+
+        // ---- what a unit case reads. The emitter builds INTO these and hands the applier the
+        // same objects, so "what was emitted" costs no copy. ----
+        const MGPFramebufferState& LastDraw() const { return m_lastDraw; }
+        const MGPFramebufferState& LastRead() const { return m_lastRead; }
+        const MGPFramebufferState& LastNamed() const { return m_lastNamed; }
+        Uint64 EmissionCount() const { return m_emissions; }
+        Uint64 RefusedCount() const { return m_refusals; }
+
         // A fresh context: what the server has is no longer what this emitter last sent. Only
-        // LATCHES reset here - the applier's object records survive a make-current and
-        // re-publishing them would move their serials for nothing.
-        void Reset() {}
+        // LATCHES reset here - MGPipeApplierReset clears the applier's DrawFramebuffer and
+        // ReadFramebuffer working state, so these mirrors have to go with them or the first
+        // emission after a make-current would be suppressed as unchanged and the server would
+        // draw into the previous context's framebuffer. The suppressor slot is invalidated by
+        // the validate point's own InvalidateAll(), beside this call.
+        void Reset() {
+            m_lastEmitted[kDraw] = 0;
+            m_lastEmitted[kRead] = 0;
+            // The per-object latch goes too, and the safe direction is why: MGPipeApplierReset
+            // keeps FramebufferRecords standing (they are object state, ID-19(b)) but
+            // ReleaseObjectRecords clears the whole table, and this emitter cannot tell the two
+            // scopes apart from here. Keeping a latch across a table that may have been dropped
+            // would suppress the one record that had to go out; dropping it costs one extra
+            // 304-byte record per named framebuffer after a context switch.
+            m_named.clear();
+        }
+
+        void ResetCounters() { m_emissions = m_refusals = 0; }
+
+        void ResetForTest() {
+            Reset();
+            ResetCounters();
+            m_lastDraw = MGPFramebufferState{};
+            m_lastRead = MGPFramebufferState{};
+            m_lastNamed = MGPFramebufferState{};
+        }
+
+    private:
+        static constexpr SizeT kDraw = 0;
+        static constexpr SizeT kRead = 1;
+
+        Uint64 Emit(const MGPFramebufferState& state) {
+            if (state.Target == static_cast<Uint8>(MGPipeFramebufferTarget::Named)) {
+                m_lastNamed = state;
+            } else if (state.Target == static_cast<Uint8>(MGPipeFramebufferTarget::Read)) {
+                m_lastRead = state;
+            } else {
+                m_lastDraw = state;
+                if (state.Target == static_cast<Uint8>(MGPipeFramebufferTarget::Both)) m_lastRead = state;
+            }
+            MGPipeApplySetFramebufferState(state);
+            ++m_emissions;
+            if (MG_Util::PipeStats::Enabled()) {
+                MG_Util::PipeStats::AddCalls(MG_Util::PipeStats::CallClass::FramebufferEmissions, 1);
+            }
+            return sizeof(MGPFramebufferState);
+        }
+
+        // ONE RECORD DESCRIBES ONE FRAMEBUFFER OBJECT - the one named by `fbo` - and every
+        // field in it is a property of THAT object. Target is the only binding-specific one.
+        //
+        // ReadSurface IS RESOLVED FROM THIS FRAMEBUFFER'S OWN READ BUFFER UNDER EVERY TARGET,
+        // Named included (c0e / MGPipeTypes.h). v1 resolved a Draw record's ReadSurface from
+        // the READ-bound object, which was D-C2's letter and muddled in substance: the record
+        // then described a surface that is not part of the framebuffer its own Fbo names, and a
+        // glReadBuffer on the read FBO moved the DRAW record's ContentHash and forced a
+        // redundant draw emission. Resolving it per object is what makes the
+        // read-buffer-shared-FBO defect class unrepresentable rather than merely fixed - the
+        // record carries a surface, not an index, and no field of it refers to "whatever is
+        // bound".
+        Bool BuildFramebufferState(const FramebufferObject& fbo, MGPipeFramebufferTarget target,
+                                   MGPFramebufferState& out) {
+            // D-C3, THE CLIENT HALF OF THE BRING-UP REFUSAL. The wire array is 8 wide and
+            // GetDynamicParameters().MaxColorAttachments is the driver's raw ES cap, not
+            // clamped to 8 on the GLES path. An attachment point at or above the wire width
+            // cannot be carried at all, so the record is REFUSED and the legacy arm runs -
+            // truncating it silently is exactly the bug class this phase is closing. The
+            // backend half of the same refusal (bit 9 declined at its first lookup, with one
+            // ERROR naming the cap) rides ResolveFramebufferSubsystemArm.
+            for (Int point = static_cast<Int>(FramebufferAttachmentType::Color0) +
+                             static_cast<Int>(kMGPipeMaxColorAttachments);
+                 point <= static_cast<Int>(FramebufferAttachmentType::ColorMax); ++point) {
+                if (fbo.GetAttachment(static_cast<FramebufferAttachmentType>(point)).IsEmpty()) continue;
+                MGLOG_E_ONCE("MGPipe: framebuffer %u has an attachment at colour point %d, which is at or "
+                             "above the wire width of %u - set_framebuffer_state is refused rather than "
+                             "truncated and the legacy arm runs",
+                             fbo.GetExternalIndex(),
+                             point - static_cast<Int>(FramebufferAttachmentType::Color0),
+                             static_cast<Uint>(kMGPipeMaxColorAttachments));
+                ++m_refusals;
+                return false;
+            }
+
+            // m2, THE SAME REFUSAL ONE FIELD OVER. A draw-buffer token may name a colour point
+            // at or above the wire width with nothing attached there, which the loop above
+            // cannot see; MGPipeDrawBufferIndex would then write 8..31 into an 8-wide array.
+            {
+                const auto& tokens = fbo.GetDrawBuffers();
+                for (SizeT i = 0; i < kMGPipeMaxColorAttachments; ++i) {
+                    if (MGPipeDrawBufferIsInsideTheWireWidth(tokens[i])) continue;
+                    MGLOG_E_ONCE("MGPipe: framebuffer %u names colour point %d in draw buffer %u, which is "
+                                 "at or above the wire width of %u - set_framebuffer_state is refused "
+                                 "rather than truncated and the legacy arm runs",
+                                 fbo.GetExternalIndex(),
+                                 static_cast<Int>(tokens[i]) -
+                                     static_cast<Int>(FramebufferAttachmentType::Color0),
+                                 static_cast<Uint>(i), static_cast<Uint>(kMGPipeMaxColorAttachments));
+                    ++m_refusals;
+                    return false;
+                }
+            }
+
+            out = MGPFramebufferState{};
+            out.Fbo = HandleFor(fbo);
+            out.Target = static_cast<Uint8>(target);
+            out.IsDefault = fbo.IsDefaultFramebuffer() ? 1 : 0;
+
+            // THE COLOUR POINTS. A default framebuffer keeps its one colour surface under
+            // BackLeft rather than under Color0, and the record has exactly one place to put
+            // it: Color[0], which is also the index MGPipeDrawBufferIndex maps that token to,
+            // so the array and the draw-buffer indices agree by construction.
+            if (out.IsDefault != 0) {
+                out.Color[0] = SurfaceOf(fbo, FramebufferAttachmentType::BackLeft);
+            } else {
+                for (SizeT i = 0; i < kMGPipeMaxColorAttachments; ++i) {
+                    out.Color[i] = SurfaceOf(fbo, static_cast<FramebufferAttachmentType>(
+                                                      static_cast<Int>(FramebufferAttachmentType::Color0) +
+                                                      static_cast<Int>(i)));
+                }
+            }
+            out.Depth = SurfaceOf(fbo, FramebufferAttachmentType::Depth);
+            out.Stencil = SurfaceOf(fbo, FramebufferAttachmentType::Stencil);
+            out.ReadSurface = SurfaceOf(fbo, fbo.GetReadBuffer());
+
+            const auto& drawBuffers = fbo.GetDrawBuffers();
+            for (SizeT i = 0; i < kMGPipeMaxColorAttachments; ++i) {
+                out.DrawBuffers[i] = MGPipeDrawBufferIndex(drawBuffers[i]);
+            }
+
+            FillGeometry(fbo, out);
+            // Complete is FramebufferObject::CheckCompleteness(), the FRONTEND-ONLY answer, and
+            // never glCheckFramebufferStatus's: that entry point additionally consults the
+            // backend's probed format-capability cache, and a client emitting it would be
+            // reading the backend from the client side - the exact coupling this boundary
+            // exists to remove. glCheckFramebufferStatus keeps answering from the frontend
+            // exactly as it does today.
+            out.Complete = fbo.CheckCompleteness() ? 1 : 0;
+            out.ContentHash = MGPipeFramebufferStateContentHash(out);
+            return true;
+        }
+
+        static Bool IsBoundTo(const FramebufferObject& fbo, MobileGL::FramebufferTarget target) {
+            if (MG_State::pGLContext == nullptr) return false;
+            const auto& bound = MG_State::pGLContext->GetFramebufferBindingSlot(target).GetBoundObject();
+            return bound && bound.get() == &fbo;
+        }
+
+        struct NamedEntry {
+            Uint32 Gen = 0;
+            Uint64 LastHash = 0;
+            Bool Has = false;
+        };
+
+        NamedEntry& NamedEntryFor(MGPipeHandle fbo) {
+            const SizeT slot = fbo.Slot;
+            if (slot >= m_named.size()) m_named.resize(slot + 1);
+            return m_named[slot];
+        }
+
+        MGPSurface SurfaceOf(const FramebufferObject& fbo, FramebufferAttachmentType type) {
+            if (type == FramebufferAttachmentType::None || type == FramebufferAttachmentType::Unknown) {
+                return MGPipeEmptySurface();
+            }
+            const auto& attachment = fbo.GetAttachment(type);
+            if (attachment.IsEmpty()) return MGPipeEmptySurface();
+            MGPipeTextureEmitter& textures = MGPipeTextureEmitterInstance();
+            // D-A4's two producers: an attachment point is what sets RENDER_TARGET and
+            // DEPTH_STENCIL, the two sticky bind bits nothing set before P4a. Sticky and ORed,
+            // so a texture that was ever a colour attachment keeps saying so, and the mask is
+            // republished on the resource's next respecify.
+            const Uint16 bit = (type == FramebufferAttachmentType::Depth ||
+                                type == FramebufferAttachmentType::Stencil)
+                                   ? static_cast<Uint16>(kMGPipeBindDepthStencil)
+                                   : static_cast<Uint16>(kMGPipeBindRenderTarget);
+            MGPipeHandle res = kMGPipeNullHandle;
+            if (attachment.IsTexture()) {
+                const auto& texture = attachment.GetTexture();
+                res = textures.AcquireTexture(texture->GetLifetimeId(), texture.get());
+                textures.NoteTextureBoundAs(res, bit);
+            } else if (attachment.IsRenderbuffer()) {
+                const auto& renderbuffer = attachment.GetRenderbuffer();
+                res = textures.AcquireRenderbuffer(renderbuffer->GetLifetimeId());
+                textures.NoteRenderbufferBoundAs(res, bit);
+            }
+            return MGPipeBuildSurface(attachment, res);
+        }
+
+        // The attachments' common extent, and the ARB_framebuffer_no_attachments defaults when
+        // there is no attachment at all (GL 4.6 core table 23.24 - the shape a framebuffer with
+        // no attachments rasterizes at).
+        static void FillGeometry(const FramebufferObject& fbo, MGPFramebufferState& out) {
+            Bool found = false;
+            for (const auto& attachment : fbo.GetAllAttachmentObjects()) {
+                if (attachment.IsEmpty()) continue;
+                const IntVec3 size = attachment.GetSize();
+                if (!found) {
+                    out.Width = static_cast<Uint16>(std::clamp<Int>(size.x(), 0, 0xFFFF));
+                    out.Height = static_cast<Uint16>(std::clamp<Int>(size.y(), 0, 0xFFFF));
+                    out.Layers = static_cast<Uint16>(
+                        attachment.IsLayered() ? std::clamp<Int>(size.z(), 1, 0xFFFF) : 1);
+                    if (attachment.IsTexture()) {
+                        const auto& texture = attachment.GetTexture();
+                        out.Samples = static_cast<Uint16>(std::max<Int>(texture->GetSamples(), 0));
+                        out.FixedSampleLocations = texture->HasFixedSampleLocations() ? 1 : 0;
+                    } else {
+                        out.Samples = static_cast<Uint16>(
+                            std::max<Int>(attachment.GetRenderbuffer()->GetSamples(), 0));
+                        out.FixedSampleLocations = 1;
+                    }
+                    found = true;
+                }
+            }
+            if (found) return;
+            out.Width = static_cast<Uint16>(std::clamp<Int>(fbo.GetDefaultWidth(), 0, 0xFFFF));
+            out.Height = static_cast<Uint16>(std::clamp<Int>(fbo.GetDefaultHeight(), 0, 0xFFFF));
+            out.Layers = static_cast<Uint16>(std::clamp<Int>(fbo.GetDefaultLayers(), 0, 0xFFFF));
+            out.Samples = static_cast<Uint16>(std::clamp<Int>(fbo.GetDefaultSamples(), 0, 0xFFFF));
+            out.FixedSampleLocations = fbo.GetDefaultFixedSampleLocations() ? 1 : 0;
+        }
+
+        Array<Uint64, 2> m_lastEmitted{};
+        // The per-FRAMEBUFFER suppressor for Named records, slot-indexed with the generation
+        // checked, exactly as the applier's own table is. A framebuffer has no wire lifetime
+        // (D-I2), so a successor simply overwrites its predecessor's entry.
+        Vector<NamedEntry> m_named;
+        MGPFramebufferState m_lastDraw{};
+        MGPFramebufferState m_lastRead{};
+        MGPFramebufferState m_lastNamed{};
+        Uint64 m_emissions = 0;
+        Uint64 m_refusals = 0;
     };
 
     inline MGPipeFramebufferEmitter& MGPipeFramebufferEmitterInstance() {

MobileGL/MG_Impl/Pipe/ImageEmit.h

@@ -33,23 +33,135 @@
 // THIS FILE IS CREATED BY THE CONTRACT COMMIT AND FILLED BY THE PACKAGE THAT OWNS IT - see
 // FramebufferEmit.h for why, in full.
 #if MOBILEGL_PIPE_PUSH
+#include <MG_Impl/Pipe/SamplerEmit.h>
+#include <MG_Impl/Pipe/SetHashSuppressor.h>
+#include <MG_Impl/Pipe/SlotAllocator.h>
 #include <MG_Pipe/MGPipe.h>
 #include <MG_Pipe/PipeApply.h>
 #include <MG_State/GLState/Core.h>
+#include <MG_State/GLState/TextureState/TextureState.h>
+#include <MG_Util/Metrics/PipeStats.h>
+
+#include <xxhash.h>
 
 namespace MobileGL::MG_Pipe {
 
-    // STUB AT THE CONTRACT COMMIT: emits nothing, returns 0 payload bytes.
+    // D-G3. Over the tail with Start and Count mixed in, the same shape the two sampler sets
+    // use - and it covers InternalFormat and Access because those are live glBindImageTexture
+    // state that the format-less image bake keys on, not decoration.
+    inline Uint64 MGPipeShaderImageSetContentHash(const MGPImageView* entries, Uint32 start, Uint32 count) {
+        Uint64 hash = XXH64(entries, static_cast<SizeT>(count) * sizeof(MGPImageView), 0);
+        hash = MGPipeMixShutter(hash, start);
+        hash = MGPipeMixShutter(hash, count);
+        return hash;
+    }
+
     class MGPipeImageEmitter {
     public:
         using GLContext = MG_State::GLState::GLContext;
 
+        // set_shader_images. Start is 0 and Count is the image-unit window described below.
+        //
+        // WHERE THE HIGH-WATER MARK COMES FROM, because the frontend has none and this is the
+        // one place a reader will look for it. DirectGLES keeps g_imageUnitHighWaterMark, but
+        // that is written from inside its own per-unit sync and lives on the far side of the
+        // boundary; TextureState::NoteUnitTouched is the TEXTURE-unit path and
+        // glBindImageTexture does not reach it. Adding a counter to TextureState would edit
+        // another package's file and resize the pull build's object, which G1 forbids outright.
+        //
+        // So the window is derived instead, from the one thing that decides whether an image
+        // unit can matter at all: the highest image unit the CURRENT PROGRAM names, memoised
+        // per program state in SamplerEmit.h's shared inversion, UNIONED with a sticky mark of
+        // every unit this emitter has already described. A program with no image uniforms
+        // gives MaxImageUnit == -1 and, with nothing sticky yet, a window of 0 - which is the
+        // zero early-out, taken BEFORE any hash and before any 192-entry walk, exactly as
+        // property 1 requires. The mark is sticky so that a program which stops naming a unit
+        // does not silently stop describing it: the window only grows, and shrinking it is how
+        // a stale binding would become invisible to the server.
         Uint64 EmitShaderImages(GLContext& ctx) {
-            (void)ctx;
-            return 0;
+            const auto& program = ctx.GetProgramForDraw();
+            const auto& resolution = MGPipeProgramOpaqueUnitsShared().For(program.get());
+            const Uint32 programWindow =
+                resolution.MaxImageUnit < 0 ? 0u : static_cast<Uint32>(resolution.MaxImageUnit) + 1u;
+            if (programWindow > m_window) m_window = programWindow;
+            const Uint32 count = m_window < kMGPipeMaxImageUnits ? m_window : kMGPipeMaxImageUnits;
+            // PROPERTY 1, and it is one integer test on every draw of every application that
+            // never binds an image.
+            if (count == 0) return 0;
+
+            for (Uint32 unit = 0; unit < count; ++unit) {
+                const auto& binding = ctx.GetImageTextureBinding(static_cast<Int>(unit));
+                MGPImageView& entry = m_entries[unit];
+                entry = MGPImageView{};
+                entry.Unit = unit;
+                entry.Res = binding.Texture ? MGPipeSlots().Acquire(MGPipeKind::Texture,
+                                                                    binding.Texture->GetLifetimeId())
+                                            : kMGPipeNullHandle;
+                // THE APPLICATION's format and access, verbatim. The bind-format recast and the
+                // buffer-texture split view are server-side and stay there; so does
+                // SupportsLayeredImageBinding's rule, which asks the BACKEND target after
+                // MapToBackendTextureTarget and forces layer to 0 for a non-layerable one -
+                // Adreno took a stray layer index literally. A client that pre-applied any of
+                // that would be answering a driver question from the wrong side.
+                entry.InternalFormat = static_cast<Uint32>(binding.Format);
+                entry.Layer = static_cast<Uint32>(binding.Layer);
+                entry.Level = static_cast<Uint16>(binding.Level);
+                entry.Layered = binding.Layered != GL_FALSE ? 1 : 0;
+                entry.Access = static_cast<Uint8>(MGPipeEncodeImageAccess(binding.Access));
+            }
+
+            const Uint64 hash = MGPipeShaderImageSetContentHash(m_entries.data(), 0, count);
+            if (!MGPipeSetHashSuppressorInstance().ShouldEmit(MGPipeSuppressorSlot::SetShaderImages, hash)) {
+                return 0;
+            }
+            m_lastImages = MGPShaderImages{};
+            m_lastImages.Start = 0;
+            m_lastImages.Count = count;
+            m_lastImages.ContentHash = hash;
+            MGPipeApplySetShaderImages(m_lastImages, m_entries.data());
+            ++m_imageSets;
+            if (MG_Util::PipeStats::Enabled()) {
+                MG_Util::PipeStats::AddCalls(MG_Util::PipeStats::CallClass::ShaderImageEmissions, 1);
+            }
+            return sizeof(MGPShaderImages) + static_cast<Uint64>(count) * sizeof(MGPImageView);
         }
 
-        void Reset() {}
+        // The validate point's FreshlyPrimed arm. A fresh context is a fresh set of image
+        // bindings, so the sticky window starts over; the suppressor slot this set latches is
+        // invalidated beside this call. There is no record half here at all - set_shader_images
+        // is pure working state and mints no object of its own.
+        void Reset() { m_window = 0; }
+
+        void ResetCounters() { m_imageSets = 0; }
+
+        const MGPShaderImages& LastShaderImages() const { return m_lastImages; }
+        const Array<MGPImageView, kMGPipeMaxImageUnits>& LastImageViews() const { return m_entries; }
+        Uint64 ImageSetCount() const { return m_imageSets; }
+        Uint32 Window() const { return m_window; }
+
+    private:
+        // GL_READ_ONLY / GL_WRITE_ONLY / GL_READ_WRITE folded into the one byte the wire
+        // carries. A value the enum does not name would otherwise truncate silently into a
+        // Uint8, which is the class of bug the descriptors exist to close.
+        static Uint32 MGPipeEncodeImageAccess(GLenum access) {
+            switch (access) {
+            case GL_READ_ONLY:
+                return 0;
+            case GL_WRITE_ONLY:
+                return 1;
+            case GL_READ_WRITE:
+                return 2;
+            default:
+                MOBILEGL_ASSERT(false, "glBindImageTexture access 0x%x is not one of the three GL names",
+                                static_cast<Uint>(access));
+                return 0;
+            }
+        }
+
+        Array<MGPImageView, kMGPipeMaxImageUnits> m_entries{};
+        MGPShaderImages m_lastImages{};
+        Uint32 m_window = 0;
+        Uint64 m_imageSets = 0;
     };
 
     inline MGPipeImageEmitter& MGPipeImageEmitterInstance() {

MobileGL/MG_Impl/Pipe/PipeFill.cpp

@@ -875,15 +875,197 @@ namespace MobileGL::MG_Pipe {
         using MG_State::GLState::RenderbufferObject;
         using MG_State::GLState::SamplerObject;
 
-        // THE SAME PAIR `wants()` APPLIES TO EVERY EMISSION at the validate point, and it is
+        // THE FOUR FAMILIES P4a MIGRATES, as one mask, so the consumer rule below is stated
+        // once instead of four times. It is deliberately NOT kMGPipeSubsystemsMigratedAtP4a
+        // (which is 0x1fff, every bit through P4a): the rule belongs to the families this
+        // phase adds and to no earlier one.
+        inline constexpr Uint64 kMGPipeP4aFamilySubsystems =
+            kMGPipeSubsystemFramebuffer | kMGPipeSubsystemTextureResources |
+            kMGPipeSubsystemSamplers | kMGPipeSubsystemPrograms;
+
+        // AND THE THIRD HALF, WHICH IS P3a's SECOND ONE: HAS A BACKEND REGISTERED THE CONSUMER?
+        //
+        // `MGPipeResourceSubsystemEnabled()` (above, ~:612) is bit 7 AND
+        // `MGPipeGetResourceOps() != nullptr`, and the second conjunct is not decoration - it is
+        // what keeps P3a's buffers on the legacy pull path under a backend that registers no
+        // table. DirectVulkan (Magma) is exactly that backend: it registers no
+        // MGPipeResourceOps and has none of P4a's twins. Without this conjunct the four P4a
+        // families emitted there anyway, the applier ACCEPTED every record, the emitters cleared
+        // their per-level dirty flags on that acceptance (D-D5 as amended by ID-18 M3), and
+        // Magma's legacy upload path then found nothing left to upload: 66 texture-upload-shaped
+        // DirectVulkan integration-gpu cases red on the push build at the default mask, with the
+        // pull build 966/966 green (ID-39).
+        //
+        // ALL FOUR FAMILIES RIDE THE ONE SIGNAL, and the reason is D-D1: a texture and a
+        // renderbuffer are RESOURCE rows - they travel on P3a's own resource_create /
+        // resource_respecify / resource_subdata catalogue, whose consumer IS this table - so the
+        // texture family's gate is P3a's gate by construction. The other three name texture
+        // handles and cannot be live without it (MGPSurface::Res is a texture or renderbuffer
+        // handle, MGPBoundView::Texture and MGPImageView::Res are texture handles, and
+        // MGPTextureParams is addressed by one), so they follow. There is no fifth signal to
+        // invent and no per-family registration to add: a backend that consumes P4a records
+        // consumes resource rows first.
+        //
+        // A BACKEND THAT REGISTERS ONE IS UNAFFECTED. DirectGLES (Espryt) registers the table
+        // at RegisterBufferBackendOps, unconditionally and at bring-up, so every predicate
+        // below answers exactly what it answered before this commit.
+        //
+        // THE REGISTER/UNREGISTER WINDOW IS THE SAME ONE P3a LIVES WITH, and it is closed the
+        // same way: UnregisterBufferBackendOps nulls the table at context teardown and the
+        // re-register happens at the next MakeCurrent, so an object born in that window never
+        // publishes a create and latches Published = false - after which the family's own
+        // self-healing create on the next respecify (TextureEmit.h ~:576 / ~:709, the shape
+        // MGPipeEmitResourceRespecify above uses for buffers) publishes it. Nothing here needs
+        // to remember the window.
+        Bool P4aFamilyHasItsConsumer(Uint64 subsystem) {
+            return (subsystem & kMGPipeP4aFamilySubsystems) == 0 ||
+                   MGPipeGetResourceOps() != nullptr;
+        }
+
+        // ================================================================================
+        // AND THE FOURTH HALF: D-K2's DEPENDENCY TABLE, ON THE CLIENT (S-3, ID-41)
+        // ================================================================================
+        //
+        // THE DEFECT THIS CLOSES. Espryt's four `Resolve<Family>SubsystemArm()` functions
+        // (Managers.cpp ~:3595-3745) REFUSE a family whose D-K2 dependency bit is clear and run
+        // the legacy arm instead - the shape ResolveVertexInputSubsystemArm's bit-8-requires-
+        // bit-7 refusal set as the precedent. That refusal is a BACKSTOP and it cannot restore a
+        // correct picture on its own, because the client's emission was gated on the operator's
+        // mask ALONE: at 0x7ff (bit 10 set, bit 11 clear) the client emitted the whole texture
+        // family, the applier accepted it, the emitter cleared each level's per-level dirty flag
+        // on that acceptance (D-D5 as amended by ID-18 M3) - and then the server refused bit 10
+        // and ran the legacy path, which found nothing left to upload. 438/491 on the DirectGLES
+        // integration lane, the same 47 texture-upload failures ID-39 saw on Magma for the
+        // consumer-less version of exactly this mistake.
+        //
+        // So the rule is the SAME "nothing at all, not less" rule as the consumer conjunct
+        // above: with a dependency unmet the client emits NOTHING for that family and the legacy
+        // pull path runs untouched, on both sides of the boundary.
+        //
+        // THE TABLE IS WRITTEN ONCE, HERE, and every one of its rows is the client mirror of the
+        // refusal Espryt already implements, bit for bit and non-transitively - the two must say
+        // the SAME thing, because a client that withheld more than the server refuses would
+        // leave the server's handle arm live with no records to read, and a client that withheld
+        // less is the defect above.
+        struct P4aFamilyDependencyRow {
+            Uint64 Family;   // exactly one bit, and it is one of kMGPipeP4aFamilySubsystems
+            Uint64 Requires; // the bits MOBILEGL_PIPE_PUSH must ALSO carry for it to be live
+        };
+
+        inline constexpr P4aFamilyDependencyRow kMGPipeP4aFamilyDependencies[] = {
+            // BIT 9 REQUIRES BIT 10. Every MGPSurface::Res in a set_framebuffer_state record
+            // names a Texture or a Renderbuffer handle, and only bit 10 populates those two slot
+            // tables (Managers.cpp ResolveFramebufferSubsystemArm).
+            {kMGPipeSubsystemFramebuffer, kMGPipeSubsystemTextureResources},
+
+            // BIT 10 REQUIRES BIT 7 - a buffer texture's MGPResourceDesc::BufferForTexBuffer
+            // names a Buffer handle and only bit 7 puts twins in the resource slot table (D-D1,
+            // ResolveTextureResourceSubsystemArm's first row) - AND BIT 11, which is D-K2's
+            // FOURTH row (ID-14/ID-15): MGPTextureParams::BuiltinSampler is a SamplerCso HANDLE,
+            // only bit 11 mints sampler CSOs (c0b's four unconditional mints deliberately
+            // exclude it), and the applier's verdict for a null one is Fatal{ProtocolCorruption}
+            // rather than a decline. The brief's original "bit 10 without 11 is fine" is
+            // WITHDRAWN for P4a as built.
+            {kMGPipeSubsystemTextureResources,
+             kMGPipeSubsystemResources | kMGPipeSubsystemSamplers},
+
+            // BIT 11 REQUIRES BIT 10. Every MGPBoundView::Texture and every MGPImageView::Res
+            // names a Texture handle and only bit 10 populates that slot table; without it every
+            // per-unit lookup would miss and the walk would `continue` WITHOUT unbinding
+            // (ResolveSamplerSubsystemArm). With the row above this is SYMMETRIC: bits 10 and 11
+            // are one arm with two switches, and the only two masks that reach either handle arm
+            // are "both set" and "neither set".
+            {kMGPipeSubsystemSamplers, kMGPipeSubsystemTextureResources},
+
+            // BIT 12 DEPENDS ON NOTHING, and that is a ROW rather than an absence so the table
+            // covers the four families exhaustively (the static_assert below): a ShaderCso handle
+            // names no texture and no buffer, the archive rides beside the record as a companion
+            // pointer, and the extra inputs the server specialises on are read from state the
+            // backend already holds (ResolveProgramSubsystemArm).
+            {kMGPipeSubsystemPrograms, 0},
+        };
+
+        // THE MIRROR PAIRS THAT STAY FINE, said out loud rather than left as an absence, because
+        // an unreachable branch that says something different is how the reachable one drifts
+        // (Managers.cpp's own words at :2377-2381) - and because the table is only trustworthy if
+        // what it does NOT contain was decided rather than forgotten:
+        //   - bit 10 set, bit 9 clear: FINE. The legacy FBO sync reaches the texture twin through
+        //     SyncTextureObjectToBackend, which dispatches to the handle arm by itself.
+        //   - bit 11 set, bit 9 clear: FINE, for the same reason - a sampler view names a texture,
+        //     never a framebuffer.
+        //   - bit 7 set, bit 10 clear: FINE, and it is P3a's shipped configuration.
+        //   - bit 12 set with any or none of 9/10/11: FINE, per the last row.
+        //   - bit 10 set, bit 11 clear (and its mirror) is NOT fine and is the row above; this is
+        //     the one sentence in the brief that P4a as built withdrew.
+        constexpr Uint64 P4aFamilyDependencyBits(Uint64 subsystem) {
+            Uint64 required = 0;
+            for (const P4aFamilyDependencyRow& row : kMGPipeP4aFamilyDependencies) {
+                if ((subsystem & row.Family) != 0) required |= row.Requires;
+            }
+            return required;
+        }
+
+        // The table covers the four families this phase migrates and nothing else, so a fifth
+        // family added to kMGPipeP4aFamilySubsystems without a row here does not silently inherit
+        // "depends on nothing".
+        constexpr Uint64 P4aFamilyDependencyTableCoverage() {
+            Uint64 covered = 0;
+            for (const P4aFamilyDependencyRow& row : kMGPipeP4aFamilyDependencies) covered |= row.Family;
+            return covered;
+        }
+        static_assert(P4aFamilyDependencyTableCoverage() == kMGPipeP4aFamilySubsystems,
+                      "every P4a family needs a D-K2 dependency row, even an empty one");
+        static_assert(P4aFamilyDependencyBits(kMGPipeSubsystemFramebuffer) ==
+                          kMGPipeSubsystemTextureResources,
+                      "bit 9 requires bit 10");
+        static_assert(P4aFamilyDependencyBits(kMGPipeSubsystemTextureResources) ==
+                          (kMGPipeSubsystemResources | kMGPipeSubsystemSamplers),
+                      "bit 10 requires bit 7 and bit 11");
+        static_assert(P4aFamilyDependencyBits(kMGPipeSubsystemSamplers) ==
+                          kMGPipeSubsystemTextureResources,
+                      "bit 11 requires bit 10");
+        static_assert(P4aFamilyDependencyBits(kMGPipeSubsystemPrograms) == 0, "bit 12 depends on nothing");
+        // No family may depend on itself: a row that did would be unfalsifiable (its own bit is
+        // set by the time the conjunct is evaluated) and would read as a dependency nobody has.
+        static_assert((P4aFamilyDependencyBits(kMGPipeSubsystemFramebuffer) &
+                       kMGPipeSubsystemFramebuffer) == 0 &&
+                          (P4aFamilyDependencyBits(kMGPipeSubsystemTextureResources) &
+                           kMGPipeSubsystemTextureResources) == 0 &&
+                          (P4aFamilyDependencyBits(kMGPipeSubsystemSamplers) &
+                           kMGPipeSubsystemSamplers) == 0,
+                      "a D-K2 row must not name its own family");
+        // The default mask carries every dependency, so the shipped arm is unchanged by all of
+        // this - the table only ever narrows a HAND-PICKED A/B mask.
+        static_assert((kMGPipeSubsystemsMigratedAtP4a &
+                       P4aFamilyDependencyBits(kMGPipeP4aFamilySubsystems)) ==
+                          P4aFamilyDependencyBits(kMGPipeP4aFamilySubsystems),
+                      "the P4a phase mask must satisfy every dependency it declares");
+
+        // IT IS THE RUNTIME BIT THAT IS TESTED, NOT THE OTHER FAMILY'S LIVENESS, and that is
+        // deliberate: Espryt's resolvers classify their arms from MOBILEGL_PIPE_PUSH alone, so
+        // testing anything else here would make the two sides disagree at some mask - which is
+        // the failure this whole commit is about, one level up. The mask is passed in rather than
+        // read, so the walk's single read of MG_Config::Features.PipePush stays the one read a
+        // whole validate point resolves against.
+        Bool P4aFamilyDependenciesAreSet(Uint64 subsystem, Uint64 pushMask) {
+            const Uint64 required = P4aFamilyDependencyBits(subsystem);
+            return (pushMask & required) == required;
+        }
+
+        // THE SAME QUADRUPLE `wants()` APPLIES TO EVERY EMISSION at the validate point, and it is
         // deliberately the same predicate rather than a second copy of it: the operator's
-        // per-subsystem A/B bit in MOBILEGL_PIPE_PUSH, AND this build having WIRED the family
-        // at all. The second half is the family's own kMGPipeWired*Subsystem constant, which
-        // lives in the family's emit header and is 0 until the commit that gives the emitter
-        // its body - so a client path that lands before its emitter does is inert by
-        // construction rather than by everyone remembering to check.
+        // per-subsystem A/B bit in MOBILEGL_PIPE_PUSH, this build having WIRED the family
+        // at all, AND - for a P4a family - a backend having registered the consumer and every
+        // D-K2 dependency bit of the family being set. The second half is the family's own
+        // kMGPipeWired*Subsystem constant, which lives in the family's emit header and is 0 until
+        // the commit that gives the emitter its body - so a client path that lands before its
+        // emitter does is inert by construction rather than by everyone remembering to check; the
+        // third is P4aFamilyHasItsConsumer above and the fourth is P4aFamilyDependenciesAreSet.
         Bool FamilyIsLive(Uint64 subsystem, Uint64 wired) {
-            return (MG_Config::Features.PipePush & subsystem) != 0 && (wired & subsystem) != 0;
+            const Uint64 pushMask = MG_Config::Features.PipePush;
+            return (pushMask & subsystem) != 0 && (wired & subsystem) != 0 &&
+                   P4aFamilyHasItsConsumer(subsystem) &&
+                   P4aFamilyDependenciesAreSet(subsystem, pushMask);
         }
 
         // ---- THE FAMILY SEAM ----
@@ -1039,6 +1221,18 @@ namespace MobileGL::MG_Pipe {
         PublicationLatch().NoteUnpublished(kind, handle);
     }
 
+    // THE GATE ITSELF, AS AN OBSERVABLE (ID-39, widened by S-3 / ID-41). Every P4a birth hook
+    // below and every `wants()` row in the walk resolve through FamilyIsLive /
+    // P4aFamilyHasItsConsumer / P4aFamilyDependenciesAreSet, and none of the three is reachable
+    // from a test - so this is the one door a unit case has onto the answer, and it is the SAME
+    // expression rather than a second copy of it. A subsystem outside kMGPipeP4aFamilySubsystems
+    // answers the pair the P2/P3a families have always answered (its consumer conjunct is
+    // vacuous and its dependency set is empty), which is what makes "nothing that emits today
+    // changes" checkable instead of asserted.
+    Bool MGPipeP4aFamilyEmits(Uint64 subsystem, Uint64 wired) {
+        return FamilyIsLive(subsystem, wired);
+    }
+
     void MGPipeMintTextureHandle(ITextureObject& texture) {
         MGPipeSlots().Acquire(MGPipeKind::Texture, texture.GetLifetimeId());
     }
@@ -2171,7 +2365,7 @@ namespace MobileGL::MG_Pipe {
         // would be a second copy of that map in the only path that runs, and mis-gating a bit
         // in it would pass every test the map has.
         //
-        // FOUR CONDITIONS, AND THE WIRED MASK IS ONE OF THEM. `kMGPipeWiredSubsystems` is the
+        // FIVE CONDITIONS, AND THE WIRED MASK IS ONE OF THEM. `kMGPipeWiredSubsystems` is the
         // OR of the per-family constants each emit header defines, and the whole ownership
         // design rests on it MEANING what the headers, this file and the result files all say
         // it means: an emitter runs only once the commit that gave it a body set its family's
@@ -2181,11 +2375,28 @@ namespace MobileGL::MG_Pipe {
         // measure an arm nobody thinks is on - and the mirror error is worse: a family that
         // lands its body and forgets the constant would emit nothing and look broken. The
         // P2/P3a bits are all in the mask, so nothing that emits today changes.
+        //
+        // AND THE FIFTH IS P4aFamilyHasItsConsumer (ID-39), the same conjunct FamilyIsLive
+        // applies to every birth hook: a P4a family whose records nothing on this backend
+        // consumes emits NOTHING, so the legacy pull path runs exactly as it does on the pull
+        // build. It is written here rather than folded into kMGPipeWiredSubsystems because the
+        // wired mask is a property of the BUILD - a constexpr an emit header sets - and this is
+        // a property of the RUNNING BACKEND, and collapsing the two would make a bisect that
+        // lands between them unreadable. The P2/P3a bits are outside kMGPipeP4aFamilySubsystems,
+        // so the conjunct is true for every one of them and nothing that emits today changes.
+        //
+        // AND THE SIXTH IS P4aFamilyDependenciesAreSet (S-3 / ID-41), the client half of D-K2:
+        // a family one of whose dependency bits the operator left clear emits NOTHING here for
+        // the same reason - the server REFUSES that family and runs its legacy arm, and an
+        // emission the server refuses is an emission whose acceptance already cleared a frontend
+        // dirty flag the legacy arm still owed. Same table, same four families, one place.
         const Uint64 pushMask = MG_Config::Features.PipePush;
         const auto wants = [&](MGPipeDirty bit) {
             const Uint64 subsystem = MGPipeSubsystemForDirty(bit);
             return subsystem != 0 && (pushMask & subsystem) != 0 &&
                    (kMGPipeWiredSubsystems & subsystem) != 0 &&
+                   P4aFamilyHasItsConsumer(subsystem) &&
+                   P4aFamilyDependenciesAreSet(subsystem, pushMask) &&
                    (dirty & MGPipeDirtyBit(bit)) != 0;
         };
         Uint64 payloadBytes = 0;
@@ -2250,10 +2461,17 @@ namespace MobileGL::MG_Pipe {
             payloadBytes += EmitShaderState(*ctx);
         }
         // The texture drain has no dirty bit over it (see its definition); it is gated on the
-        // subsystem bit and on this build having wired the family at all, which is the same
-        // pair `wants()` applies to every other emission.
+        // subsystem bit, on this build having wired the family at all, on a backend having
+        // registered the consumer and on D-K2's dependency bits for the family being set, which
+        // is the same quadruple `wants()` applies to every other emission. The last two are the
+        // whole of ID-39 and of S-3 on the path where they mattered most: the drain is what
+        // clears a level's dirty flags on acceptance, so a drain that ran against an applier no
+        // backend reads is exactly how Magma lost its texel uploads, and a drain that ran at a
+        // mask whose bit 11 or bit 7 is clear is how Espryt lost them at 0x7ff and 0x5ff.
         if ((pushMask & kMGPipeSubsystemTextureResources) != 0 &&
-            (kMGPipeWiredSubsystems & kMGPipeSubsystemTextureResources) != 0) {
+            (kMGPipeWiredSubsystems & kMGPipeSubsystemTextureResources) != 0 &&
+            P4aFamilyHasItsConsumer(kMGPipeSubsystemTextureResources) &&
+            P4aFamilyDependenciesAreSet(kMGPipeSubsystemTextureResources, pushMask)) {
             payloadBytes += DrainTextureSubData(*ctx);
         }
         if (wants(MGPipeDirty::NewSamplerViews)) {
@@ -2326,8 +2544,15 @@ namespace MobileGL::MG_Pipe {
             // the very fields the migration just took over.
             const MGPipeFieldEmitter emitter = kMGPipeFieldEmittedBy[i];
             const Uint64 subsystem = SubsystemForEmitter(emitter);
+            // P4aFamilyHasItsConsumer and P4aFamilyDependenciesAreSet are in this conjunction for
+            // the reason they are in `wants()`: "supplied" means A CALL WENT OUT CARRYING THIS
+            // FIELD, and on a backend with no consumer - or at a mask that leaves one of the
+            // family's D-K2 dependency bits clear - no P4a call went out at all, so withholding
+            // the pull here would leave the field unfilled at the very verb that reads it.
             const Bool supplied = subsystem != 0 && (subsystem & kMGPipeWiredSubsystems) != 0 &&
                                   (pushMask & subsystem) != 0 &&
+                                  P4aFamilyHasItsConsumer(subsystem) &&
+                                  P4aFamilyDependenciesAreSet(subsystem, pushMask) &&
                                   EmittedCallSuppliesTheWholeField(field) &&
                                   (applierDerives || AppliedWithoutDerivation(field));
             if (!supplied) MGPipeFillAccess::CopyField(inputs, *ctx, field);

MobileGL/MG_Impl/Pipe/PipeFill.h

@@ -43,6 +43,33 @@ namespace MobileGL::MG_Pipe {
     // stop where it says it stops (MG_Test/ScopedPipeVerb.h).
     void MGPipeLeaveVerb();
 
+    // PipeFill.cpp. DOES THIS BUILD, ON THIS BACKEND, AT THIS MASK, EMIT FOR THIS P4a FAMILY?
+    // (ID-39, widened by S-3 / ID-41.) The four conjuncts are the operator's per-subsystem bit
+    // in MOBILEGL_PIPE_PUSH, the family's own kMGPipeWired*Subsystem constant (`wired`, which
+    // the caller passes because it lives in the family's emit header and this header may not
+    // include one), and - for the four families P4a migrates - a backend having registered
+    // MGPipeResourceOps (the same per-backend signal `MGPipeResourceSubsystemEnabled()` has
+    // applied to P3a's buffers since the phase began) and every D-K2 dependency bit of the
+    // family being set in the same mask.
+    //
+    // THE LAST TWO CONJUNCTS ARE THE ONES THIS DECLARATION EXISTS FOR, and they are the same
+    // defect twice. Magma (DirectVulkan) registers no table and has no P4a twins; at a mask like
+    // 0x7ff Espryt REFUSES the texture family server-side because D-K2's fourth row says bit 10
+    // requires bit 11. In both cases the client emitted anyway, the applier accepted, the
+    // emitters cleared their per-level dirty flags on that acceptance, and the legacy upload
+    // path that still owed those texels found nothing to upload (66 DirectVulkan cases at ID-39,
+    // 47 DirectGLES cases at ID-41). With them the four families emit NOTHING in that state and
+    // the legacy pull path runs exactly as it does on a pull build.
+    //
+    // D-K2's TABLE IS IN PipeFill.cpp, ONCE: bit 9 requires bit 10, bit 10 requires bits 7 and
+    // 11, bit 11 requires bit 10, bit 12 depends on nothing - the client mirror, bit for bit, of
+    // the four `Resolve<Family>SubsystemArm()` refusals in DirectGLES/Managers.cpp.
+    //
+    // It is exported for the unit gate and for no other caller: the gate itself is
+    // FamilyIsLive() inside PipeFill.cpp, every birth hook and every `wants()` row resolves
+    // through it, and this returns that same expression rather than a second copy of it.
+    Bool MGPipeP4aFamilyEmits(Uint64 subsystem, Uint64 wired);
+
     // PipeFill.cpp. P3a D-H2.1: the DRAW's raw vertex-fetch base instance, which
     // set_vertex_buffers now carries as an explicit field.
     //

MobileGL/MG_Impl/Pipe/ProgramEmit.h

@@ -36,38 +36,442 @@
 // THIS FILE IS CREATED BY THE CONTRACT COMMIT AND FILLED BY THE PACKAGE THAT OWNS IT - see
 // FramebufferEmit.h for why, in full.
 #if MOBILEGL_PIPE_PUSH
+#include <MG_Impl/Pipe/CompositeResolver.h>
+#include <MG_Impl/Pipe/SlotAllocator.h>
 #include <MG_Pipe/MGPipe.h>
+#include <MG_Pipe/MGPipeHostSpan.h>
 #include <MG_Pipe/PipeApply.h>
+#include <MG_Pipe/PipeMutation.h>
 #include <MG_State/GLState/Core.h>
+#include <MG_State/GLState/ProgramState/ProgramObject.h>
+#include <MG_Util/Metrics/PipeStats.h>
 
 namespace MobileGL::MG_Pipe {
 
-    // 0 until the emitters below have bodies; see FramebufferEmit.h's note.
-    inline constexpr Uint64 kMGPipeWiredProgramSubsystem = 0;
+    // WIRED. create/bind/delete_shader_state, set_draw_program, set_dispatch_program and
+    // set_global_constants all have bodies, so this family contributes its bit to
+    // kMGPipeWiredSubsystems.
+    //
+    // AND SINCE c0b THAT CONSTANT REALLY IS PART OF THE EMISSION GATE, so the note that used to
+    // say otherwise here was true only against the contract commit: the validate point's
+    // `wants()` asks the subsystem mapping, the operator's MOBILEGL_PIPE_PUSH mask, THIS
+    // CONSTANT and the dirty bit, and the birth hooks' `FamilyIsLive` asks the same pair one
+    // level in. It is also a compile-time contract - while it is non-zero PipeFill.cpp's
+    // `if constexpr` seam instantiates the forward to EmitShaderCso below, so a missing entry
+    // point is a build error here rather than at the merge. The RUNTIME A/B that switches the
+    // family off is still the mask. See SamplerEmit.h's twin note.
+    inline constexpr Uint64 kMGPipeWiredProgramSubsystem = kMGPipeSubsystemPrograms;
+
+    // D-H6. ~0u is the BACKENDS' "never uploaded" sentinel for a global-constants version, and
+    // ProgramObject::MarkUBOContentDirty skips it on the wrap for exactly that reason. The
+    // client must never put it on the wire either: a server that received it would read its own
+    // record as "nothing has ever been uploaded here" and re-upload for ever.
+    inline constexpr Uint32 kMGPipeGlobalConstantsNeverUploaded = ~Uint32{0};
+
+    inline constexpr Bool MGPipeGlobalConstantsVersionIsEmittable(Uint32 version) {
+        return version != kMGPipeGlobalConstantsNeverUploaded;
+    }
+
+    // A program's identity for the wire, out of the SNAPSHOT the last link consumed and never
+    // out of the live attach list: glAttachShader and glCompileShader take effect only at the
+    // NEXT link and neither moves m_linkVersion, so a stage mask built from GetAttachedShaders
+    // would describe a program that does not exist yet. GetLinkedShaderStages() is also what
+    // indexes GetGeneratedSpirv(), so the two halves of this descriptor are guaranteed to agree
+    // by construction rather than by care.
+    inline Uint32 MGPipeStageMaskOf(const MG_State::GLState::ProgramObject& program) {
+        Uint32 mask = 0;
+        for (const ShaderStage stage : program.GetLinkedShaderStages()) {
+            if (stage == ShaderStage::Unknown) continue;
+            mask |= Uint32{1} << static_cast<Uint32>(stage);
+        }
+        return mask;
+    }
 
-    // STUB AT THE CONTRACT COMMIT: emits nothing, returns 0 payload bytes.
     class MGPipeProgramEmitter {
     public:
         using GLContext = MG_State::GLState::GLContext;
+        using ProgramObject = MG_State::GLState::ProgramObject;
 
         // create_shader_state (re-issued on the SAME handle whenever the link version moves -
         // Gen moves only on slot reuse), then bind_shader_state and set_draw_program /
         // set_dispatch_program. Two program calls because the frontend has two joins and two
         // PipeInputs slots.
+        //
+        // BOTH JOINS HAPPEN HERE and both are the verb's own: GetProgramForDraw flattens a
+        // bound pipeline into its composite and GetProgramForDispatch answers the compute
+        // question, and with a plain glUseProgram they are the same object, so the ordinary
+        // frame pays one join it was going to pay anyway.
         Uint64 EmitShaderState(GLContext& ctx) {
-            (void)ctx;
-            return 0;
+            Uint64 bytes = 0;
+            const auto& drawProgram = ctx.GetProgramForDraw();
+            const auto& dispatchProgram = ctx.GetProgramForDispatch();
+
+            const MGPipeHandle drawCso =
+                drawProgram ? AcquireShaderCso(*drawProgram, bytes) : kMGPipeNullHandle;
+            // THE COMPOSITE'S SECOND RELEASE PATH is spoken here, not in a destructor: when the
+            // bound pipeline's draw-program signature moves, the resolver releases the slot the
+            // previous composite held. Whichever of the two paths runs second - this one or the
+            // composite ProgramObject's own ~ProgramObject - is a proven no-op, because the slot
+            // allocator refuses a slot that is not live at that generation.
+            if (drawProgram && MGPipeProgramIsPipelineComposite(*drawProgram)) {
+                if (const auto& pipeline = ctx.GetBoundProgramPipeline()) {
+                    // THE CONTEXT IS PART OF THE RESOLVER's KEY and this is the only place that
+                    // supplies it: the resolver is a process singleton and a pipeline's GL name
+                    // is per context, so without it a make-current between two contexts holding
+                    // one pipeline name released the other context's LIVE composite.
+                    // GetTextureContextId() is the tree's never-reused per-context id, the same
+                    // one PipeInputs carries and the backends' per-context memos key on.
+                    MGPipeCompositeResolverInstance().Observe(ctx.GetTextureContextId(), *pipeline,
+                                                             *drawProgram, drawCso);
+                }
+            }
+            const MGPipeHandle dispatchCso =
+                dispatchProgram ? (dispatchProgram == drawProgram ? drawCso
+                                                                  : AcquireShaderCso(*dispatchProgram, bytes))
+                                : kMGPipeNullHandle;
+
+            // THE BOUND CSO IS THE DRAW ONE WHEN THERE IS ONE. bind_shader_state names what
+            // glUseProgram selected, and when a program pipeline is bound instead that is the
+            // composite; a compute-only pipeline has no draw program at all, and then the
+            // dispatch program is the only thing bound. A null handle is legal here and means
+            // exactly "nothing bound".
+            const MGPipeHandle boundCso = !MGPipeHandleIsNull(drawCso) ? drawCso : dispatchCso;
+            if (boundCso != m_boundCso) {
+                MGPipeApplyBindShaderState(HandleOnly(boundCso));
+                m_boundCso = boundCso;
+                ++m_binds;
+                bytes += sizeof(MGPHandleOnly);
+            }
+            if (drawCso != m_drawCso) {
+                MGPipeApplySetDrawProgram(HandleOnly(drawCso));
+                m_drawCso = drawCso;
+                ++m_drawSets;
+                bytes += sizeof(MGPHandleOnly);
+            }
+            if (dispatchCso != m_dispatchCso) {
+                MGPipeApplySetDispatchProgram(HandleOnly(dispatchCso));
+                m_dispatchCso = dispatchCso;
+                ++m_dispatchSets;
+                bytes += sizeof(MGPHandleOnly);
+            }
+            return bytes;
         }
 
         // set_global_constants: the DEFAULT UNIFORM BLOCK only, keyed (ShaderCso, Version) and
         // at most once per program per frame. Version is GetUBOContentVersion() and must never
         // be ~0u, which is the backends' "never uploaded" sentinel - the wrap skips it.
+        //
+        // NAMED uniform blocks are NOT this call's: set_shader_buffers(Uniform) is a later
+        // phase's and BindCurrentProgramWithResources' named-UBO block is untouched. What
+        // travels here is globalUboScratch, the link phase's CPU array, which has no GL name
+        // and no BufferObject behind it.
         Uint64 EmitGlobalConstants(GLContext& ctx) {
-            (void)ctx;
-            return 0;
+            const auto& program = ctx.GetProgramForDraw();
+            if (!program) return 0;
+            const Uint32 version = program->GetUBOContentVersion();
+            // THE SENTINEL IS NEVER EMITTED. A server that received ~0u would read its own
+            // record as "never uploaded" and re-upload every frame for ever.
+            if (!MGPipeGlobalConstantsVersionIsEmittable(version)) return 0;
+            const Uint size = program->GetUBOSize();
+            if (size == 0) return 0;
+
+            Uint64 bytes = 0;
+            const MGPipeHandle cso = AcquireShaderCso(*program, bytes);
+            // (ShaderCso, Version) IS the key, so the latch is the key: an unchanged pair means
+            // the server already holds these bytes and re-sending them would move the record's
+            // serial for nothing.
+            if (cso == m_constantsCso && version == m_constantsVersion) return bytes;
+
+            m_lastConstants = MGPGlobalConstants{};
+            m_lastConstants.ShaderCso = cso;
+            m_lastConstants.Version = version;
+            // THE ONE BLOB RULE: Size 0 means "this record does not declare its blob" - which
+            // is what a monolith emission is - and the bytes ride beside it as a companion
+            // pointer. Offset carries the staging address for diagnostics only; nothing reads
+            // it as a length.
+            m_lastConstants.Blob.Seg = kMGHostSpanSegNone;
+            m_lastConstants.Blob.Offset = reinterpret_cast<Uint64>(program->GetUBOData());
+            m_lastConstants.Blob.Size = 0;
+            MGPipeApplySetGlobalConstants(m_lastConstants, program->GetUBOData());
+            m_constantsCso = cso;
+            m_constantsVersion = version;
+            ++m_constantSets;
+            if (MG_Util::PipeStats::Enabled()) {
+                MG_Util::PipeStats::AddBytes(MG_Util::PipeStats::ByteClass::CsoBlobBytes, size);
+            }
+            return bytes + sizeof(MGPGlobalConstants) + size;
         }
 
-        void Reset() {}
+        // D-H4's re-issue rule, and it is the CreateVertexElements shape one for one: the
+        // record goes out again on the SAME handle whenever the link version moves, which is
+        // legal because MGPipeHandle::Gen increments only on slot reuse and never on a
+        // respecify. A program that relinks is the same GL object and the server's twin table
+        // must not be asked to mint a second one.
+        MGPipeHandle AcquireShaderCso(const ProgramObject& program, Uint64& payloadBytes) {
+            const MGPipeHandle handle = AcquireShaderCsoHandle(program);
+            if (MGPipeHandleIsNull(handle)) return handle;
+            Latch& latch = LatchFor(handle);
+
+            const Uint32 linkVersion = program.GetLinkVersion();
+            if (latch.RecordLive && latch.RecordGen == handle.Gen && latch.LinkVersion == linkVersion) {
+                return handle;
+            }
+
+            const auto& link = program.GetLinkReflection();
+            const auto& spirv = program.GetSpirvReflection();
+
+            m_lastDesc = MGPProgramDesc{};
+            m_lastDesc.Cso = handle;
+            m_lastDesc.StageMask = MGPipeStageMaskOf(program);
+            m_lastDesc.GlobalUboSize = static_cast<Uint32>(program.GetUBOSize());
+            m_lastDesc.ReservedNumSamplesOffset = static_cast<Uint32>(spirv.reservedNumSamplesOffset);
+            m_lastDesc.SpirvStatus = spirv.spirvStatus ? 1 : 0;
+            m_lastDesc.NativeFloat64 = spirv.nativeFloat64 ? 1 : 0;
+            m_lastDesc.PointSizeDemoted = spirv.pointSizeDemoted ? 1 : 0;
+            m_lastDesc.EnableSpirvValidation = spirv.enableSpirvValidation ? 1 : 0;
+
+            // ONE BLOB REF PER MODULE, IN THE LINKED-SHADER-SNAPSHOT'S ORDER, which is the
+            // order GetGeneratedSpirv() is indexed in - so Spirv[i] and StageMask agree because
+            // they came out of the same snapshot. Every one of them declares Size 0 (the one
+            // Blob rule); Offset carries the module's staging address so a reader can see which
+            // slots are occupied without the record pretending to declare a length it does not
+            // own.
+            //
+            // A COUNTED REFUSAL AND NOT AN ASSERTION (D-J3). MOBILEGL_ASSERT compiles out at
+            // INFO, which is all three gate builds and every shipped build, so an assert here
+            // would leave the truncation below completely silent in exactly the builds that
+            // run - which is the idiom D-J3 exists to forbid. generatedSpirv cannot exceed six
+            // stages today, so this is a guard against a seventh; truncation is the safe
+            // direction and the counter is what makes it visible.
+            const SizeT moduleCount = spirv.generatedSpirv.size();
+            if (moduleCount > 6) ++m_moduleTruncations;
+            for (SizeT i = 0; i < moduleCount && i < 6; ++i) {
+                m_lastDesc.Spirv[i].Seg = kMGHostSpanSegNone;
+                m_lastDesc.Spirv[i].Offset = reinterpret_cast<Uint64>(spirv.generatedSpirv[i].data());
+                m_lastDesc.Spirv[i].Size = 0;
+            }
+            m_lastDesc.Reflection.Seg = kMGHostSpanSegNone;
+            m_lastDesc.Reflection.Offset = reinterpret_cast<Uint64>(&link);
+            m_lastDesc.Reflection.Size = 0;
+
+            MGPipeApplyCreateShaderState(m_lastDesc, &link, &spirv);
+            // THE CREATE WENT OUT, so the publication latch is taken here and nowhere else
+            // (contract-v2 §3.1). MGPipeEmitShaderCsoDestroyAndFree reads it, and without it
+            // delete_shader_state can never go out - for an ordinary program or for a
+            // composite, both of which take that one helper.
+            MGPipeNoteHandlePublished(MGPipeKind::ShaderCso, handle);
+            ++m_creates;
+            payloadBytes += sizeof(MGPProgramDesc);
+
+            // A RE-ISSUED create_shader_state CLEARS THE APPLIER's DEFAULT UNIFORM BLOCK (wire
+            // W6), so the (Cso, Version) latch that suppresses set_global_constants has to go
+            // with it or the block is never re-sent. The case the design worries about is a
+            // FAILED relink of a bound program - GL keeps the previous executable and its
+            // uniforms running - and the general one is any future re-issue trigger that does
+            // not happen to move the content version, of which a recycled slot is one.
+            // Invalidated rather than re-emitted here, because this function has no business
+            // deciding when the constants go out: the next EmitGlobalConstants sees an
+            // unlatched key and sends them.
+            if (m_constantsCso == handle) {
+                m_constantsCso = kMGPipeNullHandle;
+                m_constantsVersion = kMGPipeGlobalConstantsNeverUploaded;
+            }
+
+            latch.RecordLive = true;
+            latch.RecordGen = handle.Gen;
+            latch.LinkVersion = linkVersion;
+            return handle;
+        }
+
+        // ---- THE CONTRACT ENTRY POINT THIS FAMILY OWES (contract-v2 §3.4) ----
+        //
+        // PipeFill.cpp's MGPipeEmitShaderCsoCreate forwards here through the `if constexpr`
+        // seam keyed on kMGPipeWiredProgramSubsystem, so while that constant is non-zero this
+        // must exist and be spelled exactly like this. A thin wrapper on purpose:
+        // AcquireShaderCso above IS this family's handle rule - identity-addressed per
+        // ProgramObject, the composite band entered through the one door, the re-issue on the
+        // same handle and the publication - and a second copy of any of it here would be a
+        // second authority.
+        //
+        // THE HOOK HAS ALREADY APPLIED BOTH GATES (the operator's mask and the wired constant),
+        // so this body applies none of its own. The byte count is discarded: a birth is not a
+        // validate-point emission and has no payload budget to report into.
+        void EmitShaderCso(ProgramObject& program) {
+            Uint64 bytes = 0;
+            AcquireShaderCso(program, bytes);
+        }
+
+        // The emitter's OWN record memo - "have I already published a create_shader_state at
+        // this slot, for this generation, at this link version".
+        //
+        // IT IS NOT WHAT THE DEATH PATH ASKS, and that changed at c0b (contract-v2 §3.1/D17):
+        // MGPipeEmitShaderCsoDestroyAndFree reads A's publication latch, which is one answer
+        // per {kind, slot, gen} that all six death helpers share. This stays because the
+        // VERSION-FIRST SKIP needs it - it is the same latch AcquireShaderCso consults before
+        // it builds a descriptor - and because a unit case reads it.
+        //
+        // THE COMPOSITE BAND IS INDEXED SEPARATELY, for the allocator's own reason: the band
+        // base is 983040, so a slot-indexed vector would allocate ~983k latches for one program
+        // pipeline. Both spaces stay dense against their own high-water mark.
+        Bool RecordIsPublished(MGPipeHandle handle) const {
+            if (MGPipeHandleIsNull(handle)) return false;
+            const Vector<Latch>& table = TableOf(handle);
+            const SizeT slot = SlotIndexOf(handle);
+            if (slot >= table.size()) return false;
+            const Latch& latch = table[slot];
+            return latch.RecordLive && latch.RecordGen == handle.Gen;
+        }
+
+        // The memo's other half, and the bound-mirror clearing beside it.
+        //
+        // NO PRODUCTION CALLER TODAY, stated rather than implied: since c0b the death path
+        // reads the contract's latch and never asks an emitter. It is kept because the memo
+        // above needs a way to be told, and because everything it clears SELF-HEALS if it is
+        // not called - the slot's Gen moves on reuse, so `RecordGen == handle.Gen` refuses a
+        // stale record latch, and the three bound mirrors below hold a handle whose generation
+        // can never be handed out again, so the next EmitShaderState compares against a
+        // different handle and re-binds. Clearing them here is the cheaper answer, not the
+        // load-bearing one.
+        void NoteRecordDestroyed(MGPipeHandle handle) {
+            if (MGPipeHandleIsNull(handle)) return;
+            Vector<Latch>& table = TableOf(handle);
+            const SizeT slot = SlotIndexOf(handle);
+            if (slot < table.size() && table[slot].RecordGen == handle.Gen) {
+                table[slot] = Latch{};
+            }
+            if (m_boundCso == handle) m_boundCso = kMGPipeNullHandle;
+            if (m_drawCso == handle) m_drawCso = kMGPipeNullHandle;
+            if (m_dispatchCso == handle) m_dispatchCso = kMGPipeNullHandle;
+            if (m_constantsCso == handle) {
+                m_constantsCso = kMGPipeNullHandle;
+                m_constantsVersion = kMGPipeGlobalConstantsNeverUploaded;
+            }
+        }
+
+        // The validate point's FreshlyPrimed arm. MGPipeApplierReset clears DrawProgram,
+        // DispatchProgram and BoundShaderCso - all three are per-context WORKING STATE - so
+        // the three mirrors here go with them, or the first emission after a make-current
+        // would be suppressed as unchanged and the server would draw with the previous
+        // context's program bound.
+        //
+        // The RECORD half stays, and that is the rule rather than an oversight: the applier
+        // keeps its shader-CSO records across a make-current because a program lives in a share
+        // group, and re-publishing one would move its Serial for nothing. The global-constants
+        // key goes with the working state because its record's bytes are per (Cso, Version) and
+        // a fresh server has not been told them.
+        void Reset() {
+            m_boundCso = kMGPipeNullHandle;
+            m_drawCso = kMGPipeNullHandle;
+            m_dispatchCso = kMGPipeNullHandle;
+            m_constantsCso = kMGPipeNullHandle;
+            m_constantsVersion = kMGPipeGlobalConstantsNeverUploaded;
+            // The composite memo's freshness goes with them - and only its freshness. Its
+            // ENTRIES name composites whose frontend objects outlive the context switch, so
+            // releasing them here would emit a delete for a live program.
+            MGPipeCompositeResolverInstance().Reset();
+        }
+
+        void ResetCounters() {
+            m_creates = m_binds = m_drawSets = m_dispatchSets = m_constantSets = 0;
+            m_moduleTruncations = 0;
+        }
+
+        // ---- what a unit case reads ----
+        const MGPProgramDesc& LastProgramDesc() const { return m_lastDesc; }
+        const MGPGlobalConstants& LastGlobalConstants() const { return m_lastConstants; }
+        // THE (Cso, Version) KEY set_global_constants is suppressed against. Exposed so a case
+        // can pin that a re-issued create_shader_state invalidates it - the applier clears the
+        // block on the re-issue (wire W6), so a latch that survived it would never re-send.
+        MGPipeHandle GlobalConstantsCso() const { return m_constantsCso; }
+        Uint32 GlobalConstantsVersion() const { return m_constantsVersion; }
+        // D-J3's counted refusal: programs whose linked snapshot carried more modules than
+        // MGPProgramDesc::Spirv[] can name, and whose tail was therefore dropped.
+        Uint64 TruncatedModuleCount() const { return m_moduleTruncations; }
+        MGPipeHandle BoundCso() const { return m_boundCso; }
+        MGPipeHandle DrawCso() const { return m_drawCso; }
+        MGPipeHandle DispatchCso() const { return m_dispatchCso; }
+        Uint64 CreateCount() const { return m_creates; }
+        Uint64 BindCount() const { return m_binds; }
+        Uint64 DrawProgramSetCount() const { return m_drawSets; }
+        Uint64 DispatchProgramSetCount() const { return m_dispatchSets; }
+        Uint64 GlobalConstantsSetCount() const { return m_constantSets; }
+
+    private:
+        // THE ONE PLACE THE BAND CAN ENTER. An ordinary program's slot comes from the ordinary
+        // allocator door keyed on its lifetime id. CompositeResolver.h widens this to send a
+        // pipeline composite through MGPipeSlotAllocator::AllocateComposite instead, and
+        // nothing else about the emission changes - the server never learns a composite is a
+        // composite.
+        MGPipeHandle AcquireShaderCsoHandle(const ProgramObject& program) {
+            const Uint64 lifetimeId = program.GetLifetimeId();
+            const MGPipeHandle existing = MGPipeSlots().FindByLifetimeId(MGPipeKind::ShaderCso, lifetimeId);
+            if (!MGPipeHandleIsNull(existing)) return existing;
+            // A composite is minted off ITS OWN lifetime id, out of the reserved band, and is
+            // an ordinary ShaderCso handle in every other respect - the same kind, the same
+            // {slot, gen} rules, the same Free, the same death helper. Keying it on its own
+            // lifetime id rather than on the pipeline's signature is what makes ~ProgramObject
+            // able to release it at all, and it is why two pipelines that happen to have the
+            // same signature keep their own composite: sharing one handle between two frontend
+            // objects would let the first one's death free a slot the second still names.
+            return MGPipeProgramIsPipelineComposite(program)
+                       ? MGPipeSlots().AllocateComposite(lifetimeId)
+                       : MGPipeSlots().AllocateFor(MGPipeKind::ShaderCso, lifetimeId);
+        }
+
+        struct Latch {
+            Bool RecordLive = false;
+            Uint32 RecordGen = 0;
+            Uint32 LinkVersion = 0;
+        };
+
+        // TWO TABLES, NOT A WIDER ONE, and it is the allocator's own reason repeated where it
+        // bites a second time: the composite band starts at slot 983040, so folding a composite
+        // into the ordinary slot-indexed vector would allocate ~983k latches - and grow them
+        // again on every future push_back - for a single program pipeline. Both spaces stay
+        // dense against their own high-water mark, which is exactly what the allocator does one
+        // level down.
+        Vector<Latch>& TableOf(MGPipeHandle handle) {
+            return MGPipeIsCompositeShaderSlot(handle.Slot) ? m_compositeLatch : m_latch;
+        }
+        const Vector<Latch>& TableOf(MGPipeHandle handle) const {
+            return MGPipeIsCompositeShaderSlot(handle.Slot) ? m_compositeLatch : m_latch;
+        }
+        static SizeT SlotIndexOf(MGPipeHandle handle) {
+            return MGPipeIsCompositeShaderSlot(handle.Slot)
+                       ? static_cast<SizeT>(handle.Slot - kMGPipeShaderCsoCompositeSlotBase)
+                       : static_cast<SizeT>(handle.Slot);
+        }
+        Latch& LatchFor(MGPipeHandle handle) {
+            Vector<Latch>& table = TableOf(handle);
+            const SizeT slot = SlotIndexOf(handle);
+            if (slot >= table.size()) table.resize(slot + 1);
+            return table[slot];
+        }
+
+        static MGPHandleOnly HandleOnly(MGPipeHandle handle) {
+            MGPHandleOnly only{};
+            only.Handle = handle;
+            only.Kind = static_cast<Uint32>(MGPipeKind::ShaderCso);
+            return only;
+        }
+
+        MGPProgramDesc m_lastDesc{};
+        MGPGlobalConstants m_lastConstants{};
+
+        Vector<Latch> m_latch;
+        Vector<Latch> m_compositeLatch;
+        MGPipeHandle m_boundCso = kMGPipeNullHandle;
+        MGPipeHandle m_drawCso = kMGPipeNullHandle;
+        MGPipeHandle m_dispatchCso = kMGPipeNullHandle;
+        MGPipeHandle m_constantsCso = kMGPipeNullHandle;
+        Uint32 m_constantsVersion = kMGPipeGlobalConstantsNeverUploaded;
+
+        Uint64 m_creates = 0;
+        Uint64 m_binds = 0;
+        Uint64 m_drawSets = 0;
+        Uint64 m_dispatchSets = 0;
+        Uint64 m_constantSets = 0;
+        Uint64 m_moduleTruncations = 0;
     };
 
     inline MGPipeProgramEmitter& MGPipeProgramEmitterInstance() {

MobileGL/MG_Impl/Pipe/Tracker.h

@@ -349,6 +349,18 @@ namespace MobileGL::MG_Pipe {
             Uint64 bindings = 0;
             Uint64 constants = 0;
             Uint64 programImages = 0;
+            // THE PROGRAM INPUT OF THE PROGRAM-RESOLVED VIEW SET (P4a fable seam F-1).
+            // set_sampler_views is resolved for the program in use (SamplerEmit.h: the sampler
+            // uniform's TYPE picks which of a unit's targets is the view) and the emitter
+            // memoises that resolution on (lifetime id, link version, backend state version). A
+            // shutter that read only the texture generations therefore missed a glUseProgram:
+            // `glBindTexture x N; glUseProgram(P1); draw; glUseProgram(P2); draw` moved nothing
+            // bit 12 read, so the view set stayed P1's - and E's record epoch, keyed on the two
+            // set serials, then never rebuilt the texture sync list for P2 either. This value is
+            // that memo key, and bit 12 mixes it in below: over-firing costs one re-resolution
+            // the set-hash suppressor absorbs, under-firing left the record describing the
+            // previous program's units.
+            Uint64 opaqueUnits = 0;
             if (program) {
                 shader = MGPipeMixShutter(program->GetLifetimeId(), program->GetLinkVersion());
                 bindings = MGPipeMixShutter(
@@ -357,7 +369,16 @@ namespace MobileGL::MG_Pipe {
                                      program->GetBlockBindingVersion()),
                     program->GetUniformWriteSetVersion());
                 constants = MGPipeMixShutter(program->GetLifetimeId(), program->GetUBOContentVersion());
-                programImages = program->GetImageUnitVersion();
+                // THE IDENTITY IS MIXED IN (P4a fable seam F-2), exactly as the pipeline arm
+                // below mixes stageLinks into its half: the counter alone is a per-program
+                // number two programs routinely share - 0 == 0 for any pair that never moved an
+                // image unit through glUniform1i, and 0 == 0 against no program at all - so a
+                // glUseProgram between them fired nothing, set_shader_images' window stayed the
+                // previous program's, and a program whose only image is a BUFFER image (E's
+                // SD-4: nothing else moves between the bind and the dispatch) never reached the
+                // record at all.
+                programImages = MGPipeMixShutter(shader, program->GetImageUnitVersion());
+                opaqueUnits = MGPipeMixShutter(shader, program->GetBackendStateVersion());
             } else if (const auto& pipeline = ctx.GetBoundProgramPipeline(); pipeline) {
                 using Pipeline = MG_State::GLState::ProgramPipelineObject;
                 // THE FIELDS ARE READ DIRECTLY RATHER THAN THROUGH THE TWO FUNCTIONS THAT
@@ -401,6 +422,10 @@ namespace MobileGL::MG_Pipe {
                 Uint64 stageLinks = static_cast<Uint64>(ctx.GetBoundProgramPipelineName());
                 Uint64 stageState = 0;
                 Uint64 stageImages = 0;
+                // The per-stage sampler/image unit assignments alone (glUniform1i on a stage
+                // program's sampler moves its backend state version and reaches the composite
+                // through the uniform mirror), for bit 12's program input below.
+                Uint64 stageOpaque = 0;
                 for (SizeT stage = 0; stage < Pipeline::kGraphicsStageCount; ++stage) {
                     const auto& staged = pipeline->GetStageProgram(static_cast<ShaderStage>(stage));
                     if (!staged) continue;
@@ -412,17 +437,88 @@ namespace MobileGL::MG_Pipe {
                                                           staged->GetBlockBindingVersion())),
                         staged->GetUniformWriteSetVersion());
                     stageImages = MGPipeMixShutter(stageImages, staged->GetImageUnitVersion());
+                    stageOpaque = MGPipeMixShutter(stageOpaque, staged->GetBackendStateVersion());
                 }
                 shader = stageLinks;
                 stageState = MGPipeMixShutter(stageLinks, stageState);
                 bindings = MGPipeMixShutter(stageState, stageImages);
                 constants = stageState;
                 programImages = MGPipeMixShutter(stageLinks, stageImages);
+                opaqueUnits = MGPipeMixShutter(stageLinks, stageOpaque);
             }
             now[Index(MGPipeDirty::NewShader)] = shader;
             now[Index(MGPipeDirty::NewShaderBindings)] = bindings;
             now[Index(MGPipeDirty::NewGlobalConstants)] = constants;
 
+            // ===========================================================================
+            // THE RECORD-FIELD -> SETTER -> SHUTTER TABLE FOR THE SEVEN P4a BITS.
+            //
+            // THE RULE (P4a fable seam audit, section C.1): every field of every emitted
+            // record names the frontend setter that changes it, and that setter moves a
+            // counter the emitting bit's shutter reads - or the emission is unconditional at
+            // the setter (the resource_* family, set_texture_params). A record field whose
+            // setter moves no shutter input is a stale record with nothing to refuse: c0d
+            // (bit 13 without the bind generation), SD-0 (an image re-bind), F-1 (the
+            // program behind the view set), F-2 (the program behind the image window) and
+            // F-3 (an attached object's storage) were all this one class. DirtySurface.def
+            // cannot catch it - it maps MUTATORS to bits and cannot see that a DERIVED field
+            // depends on a mutator whose row is another family's - so the table lives here,
+            // beside the shutters, and a row is added whenever a record gains a field.
+            //
+            // bit 6  create/bind_shader_state, set_draw/dispatch_program (ProgramEmit.h)
+            //        fields: Cso, StageMask, GlobalUboSize, the artefact blob refs, the two
+            //                bound handles
+            //        setters: glUseProgram (m_currentProgram), glLinkProgram (link version),
+            //                glBindProgramPipeline / glUseProgramStages (pipeline name +
+            //                per-stage {lifetime id, link version})
+            //        shutter: lifetime id x link version, or stageLinks under a pipeline
+            // bit 7  the program's bindings (image units, block bindings, uniform write set)
+            //        setters: glUniform1i on an opaque uniform (backend state version, image
+            //                unit version), glUniformBlockBinding / glShaderStorageBlockBinding
+            //                (block binding version), any glUniform* (uniform write set)
+            //        shutter: the four per-program counters, x stageLinks under a pipeline
+            // bit 8  set_global_constants: ShaderCso, Version, the default-block image
+            //        setters: any glUniform* on the default block (UBO content version),
+            //                glUseProgram (lifetime id)
+            //        shutter: lifetime id x UBO content version, or stageState
+            // bit 11 set_framebuffer_state: Fbo, Color[8]/Depth/Stencil/ReadSurface
+            //        (Res, Kind, InternalFormat, TextureTarget, Layered, Level, Layer,
+            //        UploadTarget), DrawBuffers[8], Width/Height/Layers/Samples/
+            //        FixedSampleLocations, IsDefault, Complete, Target
+            //        setters: glFramebufferTexture*/glFramebufferRenderbuffer, glDrawBuffer(s),
+            //                glReadBuffer, glFramebufferParameteri (the attachment
+            //                aggregate); glBindFramebuffer (the two binding slot versions);
+            //                AND a storage redefinition of an ATTACHED texture or
+            //                renderbuffer - glTexImage*/glTexStorage*/glTexBuffer/
+            //                glTextureView/glRenderbufferStorage* - because InternalFormat,
+            //                TextureTarget, the extent, Samples and Complete are INLINED at
+            //                emission (D-C1): those bump the attachment aggregate from the
+            //                object's PipePublishDescriptor (F-3)
+            //        shutter: attachment aggregate x draw bind version x read bind version
+            // bit 12 set_sampler_views: per unit {View, Texture}
+            //        setters: glBindTexture / glActiveTexture (bind generation), a texture's
+            //                or a sampler object's parameters (SamplesAsIncompleteTexture -
+            //                the params aggregate), an upload that defines a level (content
+            //                aggregate), the default texture's image appearing (bind
+            //                generation, TextureObject.cpp); AND the program in use -
+            //                glUseProgram, a relink, glUniform1i on a sampler uniform (which
+            //                unit a uniform's TYPE resolves) - F-1
+            //        shutter: content x params x bind generation x opaqueUnits
+            // bit 13 bind_sampler_states: per unit the sampler CSO handle
+            //        setters: glBindSampler (bind generation, c0d), glSamplerParameter* /
+            //                glTexParameter* (params aggregate + sampling resolution),
+            //                glDeleteSamplers (bind generation)
+            //        shutter: params x sampling resolution x bind generation
+            // bit 14 set_shader_images: per unit {Res, InternalFormat, Layer, Level,
+            //        Layered, Access} over the program's image-unit window
+            //        setters: glBindImageTexture (bind generation, SD-0), a texture's
+            //                content/params, glUniform1i on an image uniform (image unit
+            //                version); AND the program in use - glUseProgram, a relink -
+            //                F-2
+            //        shutter: content x params x bind generation x programImages
+            //                (lifetime id x link version x image unit version)
+            // ===========================================================================
+
             // ---- the object-class bits 9..17 ----
             const Uint64 textureContent = ctx.GetAnyTextureContentGeneration();
             const Uint64 textureParams = ctx.GetAnyTextureParamsGeneration();
@@ -470,13 +566,24 @@ namespace MobileGL::MG_Pipe {
             // firing costs one extra push; under-firing renders stale, and this file's own
             // rule is that under-firing is the dangerous direction.
             //
-            // A RENDERBUFFER RESPECIFY IS STILL INVISIBLE HERE, and deliberately so:
-            // RenderbufferObject's SetInternalFormat / AllocateStorage / SetSamples bump no
-            // version and raise no notice, so re-storaging an ALREADY-ATTACHED renderbuffer
-            // moves neither half of this shutter. That hole is closed by emitting
-            // resource_respecify straight from the storage entry point - not by widening this
-            // shutter and not by adding a version counter to RenderbufferObject, which would
-            // resize the pull build's object and break G1.
+            // A STORAGE REDEFINITION OF AN ATTACHED OBJECT MOVES THIS SHUTTER (P4a fable seam
+            // F-3), and the sentence that stood here - "a renderbuffer respecify is still
+            // invisible here, and deliberately so ... closed by emitting resource_respecify
+            // straight from the storage entry point" - was true of the RESOURCE record only.
+            // set_framebuffer_state inlines each attachment's InternalFormat, TextureTarget,
+            // extent, Samples and Complete (D-C1: "so the four cross-object masks fall out at
+            // push time with no lookup"), so `glTexImage2D(tex, RGB8); attach; draw;
+            // glTexImage2D(tex, RGBA8); draw` left the FRAMEBUFFER record saying RGB8 while the
+            // resource record said RGBA8, and the handle arm answered its alpha-widening,
+            // snorm-clamp and integer masks from the stale copy where the legacy arm re-read
+            // the frontend at the same re-sync - a proven arm divergence on a public-GL
+            // sequence. The fix is at the SETTER, not here: TextureObjectBase::PipePublish
+            // Descriptor and RenderbufferObject::PipePublishDescriptor - the one funnel every
+            // storage-defining entry point of either object takes, push-only - bump the
+            // attachment aggregate this shutter already reads. No counter is added to either
+            // object (G1), nothing widens this shutter onto the texture-content aggregate (which
+            // would fire the 304-byte record build on every glTexSubImage2D), and a storage
+            // definition of an UNATTACHED object over-fires it exactly once at load time.
             //
             // AND A TRAP THE NEXT NARROWING WOULD WALK INTO, recorded here because it is
             // invisible from the shutter: FramebufferObject::SetDrawBuffer versions the VALUE
@@ -491,8 +598,16 @@ namespace MobileGL::MG_Pipe {
                         ctx.GetFramebufferBindingSlot(FramebufferTarget::Draw).GetVersion())),
                 m_readFramebufferBind.Observe(
                     ctx.GetFramebufferBindingSlot(FramebufferTarget::Read).GetVersion()));
-            now[Index(MGPipeDirty::NewSamplerViews)] =
-                MGPipeMixShutter(textureContent, ctx.GetTextureBindGeneration());
+            // Bit 12 reads FOUR things (F-1): the two texture aggregates, the bind generation
+            // and the program input computed above. The params aggregate is here because
+            // SamplerEmit.h drops a unit's view to null when SamplesAsIncompleteTexture says so,
+            // and that predicate reads the effective sampler's filters - a glTexParameteri(
+            // MIN_FILTER) that completes a texture fired bit 13 and not this one, so the entry
+            // stayed null. The program input is here because the set is resolved FOR THE
+            // PROGRAM IN USE, and a glUseProgram alone moved nothing this shutter read.
+            now[Index(MGPipeDirty::NewSamplerViews)] = MGPipeMixShutter(
+                MGPipeMixShutter(MGPipeMixShutter(textureContent, textureParams), ctx.GetTextureBindGeneration()),
+                opaqueUnits);
             // Bit 13, WIDENED AT P4a FOR BIT 11's REASON and found the same way. glBindSampler
             // moves NEITHER half of what this used to read: GL_Sampler.cpp's BindSampler_State
             // goes through NoteTextureUnitTouched and TextureUnit::SetSamplerObject, and both
@@ -515,8 +630,9 @@ namespace MobileGL::MG_Pipe {
             now[Index(MGPipeDirty::NewSamplers)] = MGPipeMixShutter(
                 MGPipeMixShutter(textureParams, ctx.GetSamplingResolutionGeneration()),
                 ctx.GetTextureBindGeneration());
-            now[Index(MGPipeDirty::NewShaderImages)] =
-                MGPipeMixShutter(MGPipeMixShutter(textureContent, textureParams), programImages);
+            now[Index(MGPipeDirty::NewShaderImages)] = MGPipeMixShutter(
+            MGPipeMixShutter(MGPipeMixShutter(textureContent, textureParams), programImages),
+            ctx.GetTextureBindGeneration());
             now[Index(MGPipeDirty::NewConstBuffers)] = buffers;
             now[Index(MGPipeDirty::NewShaderBuffers)] = buffers;
             now[Index(MGPipeDirty::NewSoTargets)] =

MobileGL/MG_IntegrationTest/CMakeLists.txt

@@ -53,6 +53,8 @@ add_executable(MobileGLIntegrationTest
     Harness/HeadlessGL.cpp
     Harness/BackendCapsPeek.cpp
     Harness/PipeSlotPeek.cpp
+    Harness/PipeApplyPeek.cpp
+    Harness/P4aSeamPeek.cpp
     Scenarios/OrientationScenario.cpp
     Scenarios/CrossFrameBufferScenario.cpp
     Scenarios/ResidentIndexScenario.cpp
@@ -133,6 +135,10 @@ add_executable(MobileGLIntegrationTest
     Scenarios/HandleRecycleScenario.cpp
     Scenarios/CsoContentAddressingScenario.cpp
     Scenarios/ResourceSubsystemControlScenario.cpp
+    Scenarios/TextureParamsWithoutASamplerViewScenario.cpp
+    Scenarios/TextureUploadShapeScenario.cpp
+    Scenarios/ObjectSubsystemControlScenario.cpp
+    Scenarios/P4aSeamAuditScenario.cpp
 )
 
 target_include_directories(MobileGLIntegrationTest PRIVATE
@@ -405,6 +411,60 @@ function(mgl_itest_probe_for_symbol outVar directory symbolRegex)
     set(${outVar} "${mglItestProbeHit}" PARENT_SCOPE)
 endfunction()
 
+# The same probe, over a CONJUNCTION: BOTH regexes matched ANYWHERE UNDER the directory, not
+# necessarily in the same file. outVar is set to "<file matching A> + <file matching B>" when both
+# were found and to the empty string otherwise.
+#
+# P4a needs it for exactly one question and the question cannot be asked any other way. "Does
+# MOBILEGL_PIPE_HANDLE_ABA_CONTROL defeat the identity of P4a's OBJECT kinds on this backend?" is
+# not answered by "some source reads Features.PipeHandleAbaControl" - MagmaPipeArms.h does, and its
+# consumers are Magma's VERTEX-INPUT keys, so a single-regex probe would arm the six P4a ABA
+# controls on a backend where the knob cannot reach a texture, a framebuffer, a sampler, a view or a
+# program, and every one of them would assert a corruption nothing on the tree can produce - a hard
+# red on an always-on integration-gpu lane. Nor is it answered by "some source names a P4a subsystem
+# bit", which will become true for a backend that honours the mask long before anyone wires the
+# knob. What the arm needs is BOTH FACTS TO BE TRUE OF THE BACKEND.
+#
+# DIRECTORY-WIDE RATHER THAN PER FILE, and that is review finding F-M5 rather than a preference.
+# Requiring one file to carry both makes the arming depend on the FILE LAYOUT a later package
+# chooses: a backend that wires the knob in Managers.cpp while its P4a subsystem constants live in
+# SlotTables.h satisfies the question and fails the probe, the six controls keep printing wired=0
+# and asserting the correct pixels, and NOTHING fails, warns or records that the expected flip did
+# not happen - the one failure mode a control whose flip is in the future has. The false-positive
+# this trades against is a backend that reads the knob somewhere and names a P4a bit somewhere else
+# without connecting them; that costs a red lane an engineer must look at, which is the direction
+# that gets noticed. Both spellings of the answer are printed, so the configure log says which file
+# supplied which half.
+#
+# Same staleness guarantees as the single-regex probe: CONFIGURE_DEPENDS on the glob, and every file
+# it finds appended to CMAKE_CONFIGURE_DEPENDS.
+function(mgl_itest_probe_for_two_symbols outVar directory symbolRegexA symbolRegexB)
+    file(GLOB_RECURSE mglItestProbeSources CONFIGURE_DEPENDS
+        "${directory}/*.h" "${directory}/*.hpp" "${directory}/*.cpp" "${directory}/*.c")
+    set(mglItestProbeHitA "")
+    set(mglItestProbeHitB "")
+    foreach(mglItestProbeSource IN LISTS mglItestProbeSources)
+        set_property(DIRECTORY APPEND PROPERTY CMAKE_CONFIGURE_DEPENDS "${mglItestProbeSource}")
+        if (NOT mglItestProbeHitA)
+            file(STRINGS "${mglItestProbeSource}" mglItestProbeLinesA REGEX "${symbolRegexA}")
+            if (mglItestProbeLinesA)
+                set(mglItestProbeHitA "${mglItestProbeSource}")
+            endif()
+        endif()
+        if (NOT mglItestProbeHitB)
+            file(STRINGS "${mglItestProbeSource}" mglItestProbeLinesB REGEX "${symbolRegexB}")
+            if (mglItestProbeLinesB)
+                set(mglItestProbeHitB "${mglItestProbeSource}")
+            endif()
+        endif()
+    endforeach()
+    if (mglItestProbeHitA AND mglItestProbeHitB)
+        set(${outVar} "${mglItestProbeHitA} + ${mglItestProbeHitB}" PARENT_SCOPE)
+    else()
+        set(${outVar} "" PARENT_SCOPE)
+    endif()
+endfunction()
+
 if (MOBILEGL_PIPE_PUSH)
     # DirectGLES' Track H arm, probed by the subsystem bit it is gated on rather than by
     # SlotTables.h existing: the bit is declared in the contract (MG_Pipe/MGPipe.h:77) and the
@@ -490,6 +550,91 @@ if (MOBILEGL_PIPE_PUSH)
                        "mpr entries will SKIP")
     endif()
 
+    # P4a's THIRD re-key question, per backend, and it is not either of the two above. Bits 5/6
+    # re-keyed each backend's VERTEX-INPUT memos and bit 7/8 the BUFFER's; P4a re-keys six OBJECT
+    # classes - texture, renderbuffer, framebuffer, sampler CSO, sampler view, shader CSO - behind
+    # four new subsystem bits, and a backend has to NAME one of those constants to honour
+    # MOBILEGL_PIPE_PUSH's default mask. A P4a case that read either older marker would arm its
+    # Handles arm on a tree where nothing about a texture is keyed on a handle: green for a re-key
+    # that does not exist. Probed by the constants rather than by a file, for the reason the block
+    # above gives - packages D and E choose their own file layout.
+    foreach(mglItestObjectBackend DirectGLES DirectVulkan)
+        mgl_itest_probe_for_symbol(MGL_ITEST_OBJECT_REKEY
+            "${MGL_ITEST_ROOT}/MobileGL/MG_Backend/${mglItestObjectBackend}"
+            "kMGPipeSubsystem(Framebuffer|TextureResources|Samplers|Programs)")
+        if (MGL_ITEST_OBJECT_REKEY)
+            message(STATUS "Integration tests: ${mglItestObjectBackend} is keyed on {slot, gen} for "
+                           "P4a's object families (${MGL_ITEST_OBJECT_REKEY})")
+            list(APPEND MGL_ITEST_CAPABILITY_ENV
+                "MGITEST_HANDLE_REKEY_OBJECTS_${mglItestObjectBackend}=1")
+        else()
+            message(STATUS "Integration tests: no ${mglItestObjectBackend} source names "
+                           "kMGPipeSubsystem{Framebuffer,TextureResources,Samplers,Programs} - "
+                           "HandleRecycle's six P4a cases will SKIP their Handles arm on it")
+        endif()
+
+        # ...and whether the ABA knob reaches those kinds THERE. A conjunction over the WHOLE
+        # backend directory, for the reason mgl_itest_probe_for_two_symbols states: reading the
+        # knob is not the same as steering P4a's keys with it, so the weaker single-regex evidence
+        # would turn six always-on entries into a permanent red - but requiring one FILE to carry
+        # both halves would let a backend satisfy the question and miss the probe, and the six
+        # controls would then keep asserting the correct pixels with nothing recording that the
+        # flip was forgotten (F-M5).
+        mgl_itest_probe_for_two_symbols(MGL_ITEST_OBJECT_ABA
+            "${MGL_ITEST_ROOT}/MobileGL/MG_Backend/${mglItestObjectBackend}"
+            "PipeHandleAbaControl"
+            "kMGPipeSubsystem(Framebuffer|TextureResources|Samplers|Programs)")
+        if (MGL_ITEST_OBJECT_ABA)
+            message(STATUS "Integration tests: MOBILEGL_PIPE_HANDLE_ABA_CONTROL steers "
+                           "${mglItestObjectBackend}'s P4a object keys (${MGL_ITEST_OBJECT_ABA})")
+            list(APPEND MGL_ITEST_CAPABILITY_ENV
+                "MGITEST_HANDLE_ABA_OBJECTS_${mglItestObjectBackend}=1")
+        else()
+            message(STATUS "Integration tests: MobileGL/MG_Backend/${mglItestObjectBackend} does not "
+                           "both read Features.PipeHandleAbaControl and name a P4a subsystem bit "
+                           "somewhere under it - HandleRecycle's six P4a cases will assert the "
+                           "CORRECT pixels on the AbaControl arm and say that it is not a control "
+                           "for them yet")
+        endif()
+    endforeach()
+
+    # The client-side emitter of P4a's four suppressor-visible emission counters, which is what
+    # ObjectSubsystemControl reads. Same shape and same reason as the CSO and map-persistent
+    # emitter probes above: the emitters are minted in MG_Impl/Pipe (packages B and C), header-only
+    # by design (D-P), so the question is "does any source there emit it", not "does a named file
+    # exist". Until one does, every counter in the emit[] bracket is structurally zero in BOTH arms
+    # of the A/B and an assertion about their difference would be a statement about nothing.
+    mgl_itest_probe_for_symbol(MGL_ITEST_OBJECT_EMITTER
+        "${MGL_ITEST_ROOT}/MobileGL/MG_Impl/Pipe" "FramebufferEmissions")
+    if (MGL_ITEST_OBJECT_EMITTER)
+        message(STATUS "Integration tests: P4a's object emissions have an emitter "
+                       "(${MGL_ITEST_OBJECT_EMITTER})")
+        list(APPEND MGL_ITEST_CAPABILITY_ENV "MGITEST_PIPE_OBJECT_EMITTER_PRESENT=1")
+    else()
+        message(STATUS "Integration tests: no MG_Impl/Pipe source emits FramebufferEmissions - "
+                       "ObjectSubsystemControl's emission case will SKIP")
+    endif()
+
+    # ...and the CLIENT half of the texture-upload shape, separately, because it is a different
+    # question with a different owner's file behind it (review F-m7). ctu= is emitted by PipeStats
+    # in EVERY push build whether or not anything increments it, so "the counter read zero" and
+    # "no client emitter exists" are the same number and TextureUploadShape cannot tell them apart
+    # from the summary line alone. Once package B's texture emitter lands, an emitter that stopped
+    # emitting would read exactly like no emitter at all and the two-sided assertion the scenario
+    # exists for would pass while comparing nothing. This probe is what separates them.
+    mgl_itest_probe_for_symbol(MGL_ITEST_CLIENT_TEXTURE_UPLOAD_EMITTER
+        "${MGL_ITEST_ROOT}/MobileGL/MG_Impl/Pipe" "ClientTextureUploadEmissions")
+    if (MGL_ITEST_CLIENT_TEXTURE_UPLOAD_EMITTER)
+        message(STATUS "Integration tests: the client texture-upload counter has an emitter "
+                       "(${MGL_ITEST_CLIENT_TEXTURE_UPLOAD_EMITTER}) - TextureUploadShape's "
+                       "two-sided assertion is live")
+        list(APPEND MGL_ITEST_CAPABILITY_ENV "MGITEST_PIPE_CLIENT_TEXTURE_UPLOAD_EMITTER_PRESENT=1")
+    else()
+        message(STATUS "Integration tests: no MG_Impl/Pipe source emits "
+                       "ClientTextureUploadEmissions - TextureUploadShape records the SERVER shape "
+                       "only and asserts that ctu= is zero")
+    endif()
+
     mgl_itest_probe_for_symbol(MGL_ITEST_MAGMA_ABA
         "${MGL_ITEST_ROOT}/MobileGL/MG_Backend/DirectVulkan" "PipeHandleAbaControl")
     if (MGL_ITEST_MAGMA_ABA)
@@ -502,8 +647,9 @@ if (MOBILEGL_PIPE_PUSH)
     endif()
 else()
     message(STATUS "Integration tests: pull build - HandleRecycle.{Handles,AbaControl}, "
-                   "CsoContentAddressing and ResourceSubsystemControl stay registered (G2) and SKIP: "
-                   "every arm they assert is compiled only under MOBILEGL_PIPE_PUSH")
+                   "CsoContentAddressing, ResourceSubsystemControl, ObjectSubsystemControl and "
+                   "TextureUploadShape stay registered (G2) and SKIP: every arm they assert is "
+                   "compiled only under MOBILEGL_PIPE_PUSH")
 endif()
 
 mgl_itest_join_environment(MGL_ITEST_GLES_ENVIRONMENT
@@ -939,14 +1085,15 @@ gtest_discover_tests(MobileGLIntegrationTest
 # explicit bitmask below that leaked PUSH=0 turned this lane's LEGACY_MEMOS=0 into D14's armless
 # combination: the bring-up aborted, on purpose, and the lane went red for a reason that was never
 # about handles. The mask is the PHASE default, not a hand-picked bit, so the lane keeps measuring
-# the shape that ships: it was kMGPipeSubsystemsMigratedAtP2 (0x7f) and is now
-# kMGPipeSubsystemsMigratedAtP3a (0x1ff, MG_Pipe/MGPipe.h), which adds bit 7 (resources) and bit 8
-# (vertex input). Pinning it at 0x7f after P3a would leave the Handles arm asserting the P2 shape
-# while the buffer and vertex-input handles it is supposed to be about stayed switched off - a lane
-# that still passes and no longer measures the key that ships. Each phase's constant survives as the
-# NEXT phase's A/B control, which is what ResourceSubsystemControl's Off lane uses 0x7f for.
+# the shape that ships: it was kMGPipeSubsystemsMigratedAtP2 (0x7f), then
+# kMGPipeSubsystemsMigratedAtP3a (0x1ff), and is now kMGPipeSubsystemsMigratedAtP4a (0x1fff,
+# MG_Pipe/MGPipe.h), which adds bits 9-12 - framebuffer, texture resources, samplers and programs.
+# Pinning it at 0x1ff after P4a would leave the Handles arm asserting the P3a shape while the six
+# OBJECT handles it is now also about stayed switched off - a lane that still passes and no longer
+# measures the key that ships. Each phase's constant survives as the NEXT phase's A/B control, which
+# is what ResourceSubsystemControl's Off lane uses 0x7f for and ObjectSubsystemControl's uses 0x1ff.
 if (MOBILEGL_PIPE_PUSH)
-    set(MGL_ITEST_HANDLES_ARM_KNOBS "MOBILEGL_PIPE_LEGACY_MEMOS=0" "MOBILEGL_PIPE_PUSH=0x1ff")
+    set(MGL_ITEST_HANDLES_ARM_KNOBS "MOBILEGL_PIPE_LEGACY_MEMOS=0" "MOBILEGL_PIPE_PUSH=0x1fff")
     set(MGL_ITEST_ABA_ARM_KNOBS "MOBILEGL_PIPE_HANDLE_ABA_CONTROL=1")
 else()
     set(MGL_ITEST_HANDLES_ARM_KNOBS "")
@@ -1051,33 +1198,36 @@ gtest_discover_tests(MobileGLIntegrationTest
 # only thing these four lanes are an A/B about is `no CSO content addressing` (bit 63,
 # kMGPipeBehaviourNoCsoContentAddressing), which is what separates the On lane from the Off lane.
 # Every
-# other bit is the build's shipping mask, so it moves with the phase: it was 0x7f
-# (kMGPipeSubsystemsMigratedAtP2) and is now 0x1ff (kMGPipeSubsystemsMigratedAtP3a) for the same
-# reason MGL_ITEST_HANDLES_ARM_KNOBS above moved. Left pinned at 0x7f after P3a these lanes would
-# keep passing while running on a configuration nothing ships - bits 7 (resources) and 8 (vertex
-# input) cleared - which is the "still green, no longer measuring the shape that ships" failure
-# the Handles-arm comment above rejects. The counters they read (csom / csob) are render-state and
+# other bit is the build's shipping mask, so it moves with the phase: 0x7f
+# (kMGPipeSubsystemsMigratedAtP2), then 0x1ff (kMGPipeSubsystemsMigratedAtP3a), now 0x1fff
+# (kMGPipeSubsystemsMigratedAtP4a) for the same reason MGL_ITEST_HANDLES_ARM_KNOBS above moved. Left
+# pinned at 0x1ff after P4a these lanes would keep passing while running on a configuration nothing
+# ships - bits 9-12 (framebuffer, texture resources, samplers, programs) cleared - which is the
+# "still green, no longer measuring the shape that ships" failure the Handles-arm comment above
+# rejects. NOTE THAT THE OFF LANE'S MASK MOVED TOO, from 0x80000000000001ff to
+# 0x8000000000001fff: the mask moves with the phase, the control is bit 63, and the two must not be
+# confused. The counters they read (csom / csob) are render-state and
 # are steered by neither bit, so raising the mask is behaviour-preserving for what they assert;
 # what it buys is that a CSO regression that only shows up with the P3a subsystems on can reach
 # them. (contract-review-v1.md item 11, closed here for all three lane families.)
 mgl_itest_join_environment(MGL_ITEST_GLES_CSO_ON_ENVIRONMENT
     "MOBILEGL_BACKEND_TYPE=DirectGLES" "MGITEST_CSO_LANE=content-addressed"
-    "MOBILEGL_PIPE_PUSH=0x1ff" "MOBILEGL_PIPE_STATS=1" "MOBILEGL_PIPE_STATS_PERIOD=1"
+    "MOBILEGL_PIPE_PUSH=0x1fff" "MOBILEGL_PIPE_STATS=1" "MOBILEGL_PIPE_STATS_PERIOD=1"
     "MOBILEGL_LOG_FILE_PATH=${CMAKE_CURRENT_BINARY_DIR}/cso-content-addressed-DirectGLES.log"
     ${MGL_ITEST_CAPABILITY_ENV} ${MGL_ITEST_COMMON_ENV})
 mgl_itest_join_environment(MGL_ITEST_GLES_CSO_OFF_ENVIRONMENT
     "MOBILEGL_BACKEND_TYPE=DirectGLES" "MGITEST_CSO_LANE=no-content-addressing"
-    "MOBILEGL_PIPE_PUSH=0x80000000000001ff" "MOBILEGL_PIPE_STATS=1" "MOBILEGL_PIPE_STATS_PERIOD=1"
+    "MOBILEGL_PIPE_PUSH=0x8000000000001fff" "MOBILEGL_PIPE_STATS=1" "MOBILEGL_PIPE_STATS_PERIOD=1"
     "MOBILEGL_LOG_FILE_PATH=${CMAKE_CURRENT_BINARY_DIR}/cso-no-content-addressing-DirectGLES.log"
     ${MGL_ITEST_CAPABILITY_ENV} ${MGL_ITEST_COMMON_ENV})
 mgl_itest_join_environment(MGL_ITEST_VULKAN_CSO_ON_ENVIRONMENT
     "MOBILEGL_BACKEND_TYPE=DirectVulkan" "MGITEST_CSO_LANE=content-addressed"
-    "MOBILEGL_PIPE_PUSH=0x1ff" "MOBILEGL_PIPE_STATS=1" "MOBILEGL_PIPE_STATS_PERIOD=1"
+    "MOBILEGL_PIPE_PUSH=0x1fff" "MOBILEGL_PIPE_STATS=1" "MOBILEGL_PIPE_STATS_PERIOD=1"
     "MOBILEGL_LOG_FILE_PATH=${CMAKE_CURRENT_BINARY_DIR}/cso-content-addressed-DirectVulkan.log"
     ${MGL_ITEST_CAPABILITY_ENV} ${MGL_ITEST_VULKAN_ENV})
 mgl_itest_join_environment(MGL_ITEST_VULKAN_CSO_OFF_ENVIRONMENT
     "MOBILEGL_BACKEND_TYPE=DirectVulkan" "MGITEST_CSO_LANE=no-content-addressing"
-    "MOBILEGL_PIPE_PUSH=0x80000000000001ff" "MOBILEGL_PIPE_STATS=1" "MOBILEGL_PIPE_STATS_PERIOD=1"
+    "MOBILEGL_PIPE_PUSH=0x8000000000001fff" "MOBILEGL_PIPE_STATS=1" "MOBILEGL_PIPE_STATS_PERIOD=1"
     "MOBILEGL_LOG_FILE_PATH=${CMAKE_CURRENT_BINARY_DIR}/cso-no-content-addressing-DirectVulkan.log"
     ${MGL_ITEST_CAPABILITY_ENV} ${MGL_ITEST_VULKAN_ENV})
 
@@ -1120,12 +1270,15 @@ gtest_discover_tests(MobileGLIntegrationTest
 
 # --- G12: the P3a subsystem A/B, and G10's map-persistent-roundtrips lanes ------------
 #
-# THE MASKS ARE THE TWO PHASE CONSTANTS, not hand-picked bits: 0x1ff is
-# kMGPipeSubsystemsMigratedAtP3a (the push build's default) and 0x7f is
-# kMGPipeSubsystemsMigratedAtP2, which is exactly that default with bits 7 (resources) and 8
-# (vertex input) cleared. MGPipe.h:79 keeps each phase's constant alive as the next phase's A/B
-# control for this reason, and a lane that spelled its own bit pattern would stop being the shape
-# that ships the first time the default moved.
+# THE MASKS ARE PHASE CONSTANTS, not hand-picked bits: 0x1fff is
+# kMGPipeSubsystemsMigratedAtP4a (the push build's default as of P4a) and 0x7f is
+# kMGPipeSubsystemsMigratedAtP2, which is that default with bits 7 (resources), 8 (vertex input)
+# and 9-12 (P4a's four object families) cleared. MGPipe.h keeps each phase's constant alive as the
+# next phase's A/B control for this reason, and a lane that spelled its own bit pattern would stop
+# being the shape that ships the first time the default moved. THE ON LANE MOVED TO 0x1fff WITH THE
+# PHASE and the OFF LANE'S 0x7f DID NOT: this A/B is about bit 7, and pinning its On arm at 0x1ff
+# after P4a would measure the resource emitter on a configuration nothing ships. P4a's own A/B -
+# 0x1fff against 0x1ff - is ObjectSubsystemControl's, further down.
 #
 # DirectGLES only. P3a migrates Espryt's buffer and VAO paths; Magma's buffer path is P7 and
 # registers no MGPipeResourceOps, so a DirectVulkan arm would be measuring the client emitter
@@ -1146,7 +1299,7 @@ gtest_discover_tests(MobileGLIntegrationTest
 # the field inside the push guard), exactly as the HandleRecycle Legacy lanes already rely on.
 mgl_itest_join_environment(MGL_ITEST_GLES_RESOURCE_SUBSYSTEM_ON_ENVIRONMENT
     "MOBILEGL_BACKEND_TYPE=DirectGLES" "MGITEST_RESOURCE_SUBSYSTEM_LANE=on"
-    "MOBILEGL_PIPE_PUSH=0x1ff" "MOBILEGL_PIPE_STATS=1" "MOBILEGL_PIPE_STATS_PERIOD=1"
+    "MOBILEGL_PIPE_PUSH=0x1fff" "MOBILEGL_PIPE_STATS=1" "MOBILEGL_PIPE_STATS_PERIOD=1"
     "MOBILEGL_LOG_FILE_PATH=${CMAKE_CURRENT_BINARY_DIR}/resource-subsystem-on-DirectGLES.log"
     ${MGL_ITEST_CAPABILITY_ENV} ${MGL_ITEST_COMMON_ENV})
 mgl_itest_join_environment(MGL_ITEST_GLES_RESOURCE_SUBSYSTEM_OFF_ENVIRONMENT
@@ -1180,12 +1333,12 @@ gtest_discover_tests(MobileGLIntegrationTest
 # TEST_FILTER, for the private-log reason above.
 mgl_itest_join_environment(MGL_ITEST_GLES_MPR_REGROW_ENVIRONMENT
     "MOBILEGL_BACKEND_TYPE=DirectGLES" "MGITEST_MPR_LANE=storage-buffer-regrow"
-    "MOBILEGL_PIPE_PUSH=0x1ff" "MOBILEGL_PIPE_STATS=1" "MOBILEGL_PIPE_STATS_PERIOD=1"
+    "MOBILEGL_PIPE_PUSH=0x1fff" "MOBILEGL_PIPE_STATS=1" "MOBILEGL_PIPE_STATS_PERIOD=1"
     "MOBILEGL_LOG_FILE_PATH=${CMAKE_CURRENT_BINARY_DIR}/mpr-storage-buffer-regrow-DirectGLES.log"
     ${MGL_ITEST_CAPABILITY_ENV} ${MGL_ITEST_COMMON_ENV})
 mgl_itest_join_environment(MGL_ITEST_GLES_MPR_ARENA_ENVIRONMENT
     "MOBILEGL_BACKEND_TYPE=DirectGLES" "MGITEST_MPR_LANE=large-arena-adoption"
-    "MOBILEGL_PIPE_PUSH=0x1ff" "MOBILEGL_PIPE_STATS=1" "MOBILEGL_PIPE_STATS_PERIOD=1"
+    "MOBILEGL_PIPE_PUSH=0x1fff" "MOBILEGL_PIPE_STATS=1" "MOBILEGL_PIPE_STATS_PERIOD=1"
     "MOBILEGL_LOG_FILE_PATH=${CMAKE_CURRENT_BINARY_DIR}/mpr-large-arena-adoption-DirectGLES.log"
     ${MGL_ITEST_CAPABILITY_ENV} ${MGL_ITEST_COMMON_ENV})
 
@@ -1216,7 +1369,7 @@ gtest_discover_tests(MobileGLIntegrationTest
 # four processes to truncate. The fourth case skips in both lanes for exactly that reason, saying
 # so.
 mgl_itest_join_environment(MGL_ITEST_GLES_ARENA_SUBSYSTEM_ON_ENVIRONMENT
-    "MOBILEGL_BACKEND_TYPE=DirectGLES" "MOBILEGL_PIPE_PUSH=0x1ff"
+    "MOBILEGL_BACKEND_TYPE=DirectGLES" "MOBILEGL_PIPE_PUSH=0x1fff"
     ${MGL_ITEST_CAPABILITY_ENV} ${MGL_ITEST_COMMON_ENV})
 mgl_itest_join_environment(MGL_ITEST_GLES_ARENA_SUBSYSTEM_OFF_ENVIRONMENT
     "MOBILEGL_BACKEND_TYPE=DirectGLES" "MOBILEGL_PIPE_PUSH=0x7f"
@@ -1241,6 +1394,191 @@ gtest_discover_tests(MobileGLIntegrationTest
         ENVIRONMENT "${MGL_ITEST_GLES_ARENA_SUBSYSTEM_OFF_ENVIRONMENT}"
 )
 
+# --- G12: the P4a subsystem A/B, and its dependency refusal ---------------------------
+#
+# THE MASKS ARE THE TWO PHASE CONSTANTS, exactly as the P3a block above: 0x1fff is
+# kMGPipeSubsystemsMigratedAtP4a (the push build's default) and 0x1ff is
+# kMGPipeSubsystemsMigratedAtP3a, which is that default with bits 9 (framebuffer), 10 (texture
+# resources), 11 (samplers) and 12 (programs) cleared. THIS is the phase's "new 0x1ff off-lane": the
+# constant P3a shipped survives as P4a's A/B control, and a lane that spelled its own bit pattern
+# would stop being the shape that ships the first time the default moved.
+#
+# THE THIRD AND FOURTH LANES ARE THE DEPENDENCY REFUSALS (D-K2) and they are the entries in this
+# family that are not vacuous before the emitters land, because both are decisions made from the
+# bitmask alone. A half-honoured mask is invisible in the pixels by construction, which is why each
+# needs an entry rather than a code comment.
+#
+#   0x9ff sets the sampler subsystem (bit 11) WITHOUT the texture resource subsystem (bit 10) that
+#         every MGPBoundView::Texture and MGPImageView::Res depends on.
+#   0x5ff sets the texture resource subsystem (bit 10) WITHOUT the sampler subsystem (bit 11):
+#         D-K2's fourth row (ID-15). MGPTextureParams::BuiltinSampler is a SamplerCso handle and
+#         only bit 11 mints sampler CSOs, so bit 10 alone would emit a null there and the applier's
+#         Fatal is the next thing that happens. The brief called this pair harmless; P4a as built
+#         says otherwise, and the refusal belongs in the texture family's arm resolver.
+#
+# In both, the bring-up must log ONE error naming both bits and run the legacy arm.
+#
+# ONE CASE PER LANE, through TEST_FILTER, and it is a constraint rather than a preference: each case
+# READS the library's log and the log is a per-LANE resource (the library opens it fopen(path, "w"),
+# so every process in a lane truncates it). Two entries in one lane race under `ctest -j` with a
+# failure indistinguishable from "the counter was never emitted". Same rule as the CSO lanes, the
+# map-persistent lanes and the verify arming lane.
+#
+# THE FIRST FOUR LANES ARE DirectGLES ONLY. P4a migrates Espryt's framebuffer, texture, sampler
+# and program paths; Magma's are P7 and register nothing here, so a DirectVulkan lane that measured
+# the emit[] bracket would be measuring the client emitters against a backend nobody asked to
+# change.
+#
+# THE FIFTH AND SIXTH LANES INVERT THAT, and the inversion is the point (c0f, ID-39/ID-40). "Magma
+# registers no consumer" stopped being a reason to have no lane the moment it became a THING THE
+# CLIENT MUST CHECK: P4a's families were wired without P3a's "a backend registered
+# MGPipeResourceOps" conjunct, so on Magma the client emitted, the applier ACCEPTED, the client
+# cleared its dirty flags on that acceptance and Magma's legacy path found nothing to upload - 66
+# DirectVulkan cases red, every one of them texture-upload shaped, every one of them green at
+# 0x1ff. The fix's belt (the applier refusing and counting RefusedNoConsumer) is invisible in
+# pixels and invisible in the emit[] bracket, so it needs its own entry, and it needs it on the
+# backend WITHOUT the consumer. The DirectGLES twin is the control that keeps the assertion from
+# being vacuously true of a tree where nothing emits anywhere.
+#
+# Both run at the PHASE DEFAULT (0x1fff) rather than a hand-picked mask, for the reason the whole
+# block gives: the shape that ships is the shape worth measuring.
+#
+# Registered in EVERY build, including the pull build where none of the counters exists, so that
+# `ctest -L integration-gpu` stays name-for-name identical between pull and push (gate G2). In a
+# pull build MGITEST_PIPE_PUSH_BUILD is absent and every one of these cases skips saying so.
+mgl_itest_join_environment(MGL_ITEST_GLES_OBJECT_SUBSYSTEM_ON_ENVIRONMENT
+    "MOBILEGL_BACKEND_TYPE=DirectGLES" "MGITEST_OBJECT_SUBSYSTEM_LANE=on"
+    "MOBILEGL_PIPE_PUSH=0x1fff" "MOBILEGL_PIPE_STATS=1" "MOBILEGL_PIPE_STATS_PERIOD=1"
+    "MOBILEGL_LOG_FILE_PATH=${CMAKE_CURRENT_BINARY_DIR}/object-subsystem-on-DirectGLES.log"
+    ${MGL_ITEST_CAPABILITY_ENV} ${MGL_ITEST_COMMON_ENV})
+mgl_itest_join_environment(MGL_ITEST_GLES_OBJECT_SUBSYSTEM_OFF_ENVIRONMENT
+    "MOBILEGL_BACKEND_TYPE=DirectGLES" "MGITEST_OBJECT_SUBSYSTEM_LANE=off"
+    "MOBILEGL_PIPE_PUSH=0x1ff" "MOBILEGL_PIPE_STATS=1" "MOBILEGL_PIPE_STATS_PERIOD=1"
+    "MOBILEGL_LOG_FILE_PATH=${CMAKE_CURRENT_BINARY_DIR}/object-subsystem-off-DirectGLES.log"
+    ${MGL_ITEST_CAPABILITY_ENV} ${MGL_ITEST_COMMON_ENV})
+mgl_itest_join_environment(MGL_ITEST_GLES_OBJECT_SUBSYSTEM_REFUSED_ENVIRONMENT
+    "MOBILEGL_BACKEND_TYPE=DirectGLES" "MGITEST_OBJECT_SUBSYSTEM_LANE=refused"
+    "MOBILEGL_PIPE_PUSH=0x9ff" "MOBILEGL_PIPE_STATS=1" "MOBILEGL_PIPE_STATS_PERIOD=1"
+    "MOBILEGL_LOG_FILE_PATH=${CMAKE_CURRENT_BINARY_DIR}/object-subsystem-refused-DirectGLES.log"
+    ${MGL_ITEST_CAPABILITY_ENV} ${MGL_ITEST_COMMON_ENV})
+mgl_itest_join_environment(MGL_ITEST_GLES_OBJECT_SUBSYSTEM_REFUSED_TEXTURE_ENVIRONMENT
+    "MOBILEGL_BACKEND_TYPE=DirectGLES" "MGITEST_OBJECT_SUBSYSTEM_LANE=refused-texture"
+    "MOBILEGL_PIPE_PUSH=0x5ff" "MOBILEGL_PIPE_STATS=1" "MOBILEGL_PIPE_STATS_PERIOD=1"
+    "MOBILEGL_LOG_FILE_PATH=${CMAKE_CURRENT_BINARY_DIR}/object-subsystem-refused-texture-DirectGLES.log"
+    ${MGL_ITEST_CAPABILITY_ENV} ${MGL_ITEST_COMMON_ENV})
+mgl_itest_join_environment(MGL_ITEST_GLES_OBJECT_SUBSYSTEM_CONSUMER_ENVIRONMENT
+    "MOBILEGL_BACKEND_TYPE=DirectGLES" "MGITEST_OBJECT_SUBSYSTEM_LANE=consumer"
+    "MOBILEGL_PIPE_PUSH=0x1fff" "MOBILEGL_PIPE_STATS=1" "MOBILEGL_PIPE_STATS_PERIOD=1"
+    "MOBILEGL_LOG_FILE_PATH=${CMAKE_CURRENT_BINARY_DIR}/object-subsystem-consumer-DirectGLES.log"
+    ${MGL_ITEST_CAPABILITY_ENV} ${MGL_ITEST_COMMON_ENV})
+mgl_itest_join_environment(MGL_ITEST_VULKAN_OBJECT_SUBSYSTEM_NO_CONSUMER_ENVIRONMENT
+    "MOBILEGL_BACKEND_TYPE=DirectVulkan" "MGITEST_OBJECT_SUBSYSTEM_LANE=no-consumer"
+    "MOBILEGL_PIPE_PUSH=0x1fff" "MOBILEGL_PIPE_STATS=1" "MOBILEGL_PIPE_STATS_PERIOD=1"
+    "MOBILEGL_LOG_FILE_PATH=${CMAKE_CURRENT_BINARY_DIR}/object-subsystem-no-consumer-DirectVulkan.log"
+    ${MGL_ITEST_CAPABILITY_ENV} ${MGL_ITEST_VULKAN_ENV})
+
+gtest_discover_tests(MobileGLIntegrationTest
+    TEST_PREFIX "DirectGLES.ObjectSubsystemControl.On."
+    TEST_FILTER "ObjectSubsystemControlScenario.ClearingTheP4aBitsStopsTheEmissionsAndNotThePixels"
+    DISCOVERY_TIMEOUT 30
+    PROPERTIES
+        LABELS integration-gpu
+        TIMEOUT ${MGL_ITEST_TIMEOUT}
+        ENVIRONMENT "${MGL_ITEST_GLES_OBJECT_SUBSYSTEM_ON_ENVIRONMENT}"
+)
+gtest_discover_tests(MobileGLIntegrationTest
+    TEST_PREFIX "DirectGLES.ObjectSubsystemControl.Off."
+    TEST_FILTER "ObjectSubsystemControlScenario.ClearingTheP4aBitsStopsTheEmissionsAndNotThePixels"
+    DISCOVERY_TIMEOUT 30
+    PROPERTIES
+        LABELS integration-gpu
+        TIMEOUT ${MGL_ITEST_TIMEOUT}
+        ENVIRONMENT "${MGL_ITEST_GLES_OBJECT_SUBSYSTEM_OFF_ENVIRONMENT}"
+)
+gtest_discover_tests(MobileGLIntegrationTest
+    TEST_PREFIX "DirectGLES.ObjectSubsystemControl.Refused."
+    TEST_FILTER "ObjectSubsystemControlScenario.ASamplerBitWithoutTheTextureBitIsRefusedAndNamed"
+    DISCOVERY_TIMEOUT 30
+    PROPERTIES
+        LABELS integration-gpu
+        TIMEOUT ${MGL_ITEST_TIMEOUT}
+        ENVIRONMENT "${MGL_ITEST_GLES_OBJECT_SUBSYSTEM_REFUSED_ENVIRONMENT}"
+)
+gtest_discover_tests(MobileGLIntegrationTest
+    TEST_PREFIX "DirectGLES.ObjectSubsystemControl.RefusedTexture."
+    TEST_FILTER "ObjectSubsystemControlScenario.ATextureBitWithoutTheSamplerBitIsRefusedAndNamed"
+    DISCOVERY_TIMEOUT 30
+    PROPERTIES
+        LABELS integration-gpu
+        TIMEOUT ${MGL_ITEST_TIMEOUT}
+        ENVIRONMENT "${MGL_ITEST_GLES_OBJECT_SUBSYSTEM_REFUSED_TEXTURE_ENVIRONMENT}"
+)
+gtest_discover_tests(MobileGLIntegrationTest
+    TEST_PREFIX "DirectGLES.ObjectSubsystemControl.Consumer."
+    TEST_FILTER "ObjectSubsystemControlScenario.TheAppliersNoConsumerBeltNeverFiresBehindTheClientsGate"
+    DISCOVERY_TIMEOUT 30
+    PROPERTIES
+        LABELS integration-gpu
+        TIMEOUT ${MGL_ITEST_TIMEOUT}
+        ENVIRONMENT "${MGL_ITEST_GLES_OBJECT_SUBSYSTEM_CONSUMER_ENVIRONMENT}"
+)
+gtest_discover_tests(MobileGLIntegrationTest
+    TEST_PREFIX "DirectVulkan.ObjectSubsystemControl.NoConsumer."
+    TEST_FILTER "ObjectSubsystemControlScenario.TheAppliersNoConsumerBeltNeverFiresBehindTheClientsGate"
+    DISCOVERY_TIMEOUT 30
+    PROPERTIES
+        LABELS integration-gpu
+        TIMEOUT ${MGL_ITEST_TIMEOUT}
+        ENVIRONMENT "${MGL_ITEST_VULKAN_OBJECT_SUBSYSTEM_NO_CONSUMER_ENVIRONMENT}"
+)
+
+# --- The texture upload shape: RECORDED, NOT GATED in P4a (D-D4) ----------------------
+#
+# SSIM is blind to the box-versus-rect upload shape and the Mali cliff it hides is ~+6 ms/frame, so
+# the shape needs a number - two numbers, in fact, the server's tex[emit= box= rect= jobs=] and the
+# client's emit[ctu=], which agreeing is the whole reason both are published (D-L). What this lane
+# asserts is that the numbers could be READ, that the server bracket's own arithmetic holds and that
+# the two sides agree when both are non-zero; WHICH shape each texture took is RecordProperty'd and
+# printed for MEASUREMENTS.md. P3b/P4b turns it into a gate against a gold standard, with the Mali
+# frame-time delta published beside it - gating a shape this phase has not finished deciding would
+# either pin today's shape as the answer or fail on the change that is the next phase's point.
+#
+# Its own log path and its own single-case filter, for the per-lane-log reason above.
+mgl_itest_join_environment(MGL_ITEST_GLES_TEXTURE_UPLOAD_SHAPE_ENVIRONMENT
+    "MOBILEGL_BACKEND_TYPE=DirectGLES" "MGITEST_TEXTURE_UPLOAD_SHAPE_LANE=1"
+    "MOBILEGL_PIPE_PUSH=0x1fff" "MOBILEGL_PIPE_STATS=1" "MOBILEGL_PIPE_STATS_PERIOD=1"
+    "MOBILEGL_LOG_FILE_PATH=${CMAKE_CURRENT_BINARY_DIR}/texture-upload-shape-DirectGLES.log"
+    ${MGL_ITEST_CAPABILITY_ENV} ${MGL_ITEST_COMMON_ENV})
+
+gtest_discover_tests(MobileGLIntegrationTest
+    TEST_PREFIX "DirectGLES.TextureUploadShape."
+    TEST_FILTER "TextureUploadShapeScenario.TheEmittedUploadShapeIsRecordedAndTheTwoSidesAgree"
+    DISCOVERY_TIMEOUT 30
+    PROPERTIES
+        LABELS integration-gpu
+        TIMEOUT ${MGL_ITEST_TIMEOUT}
+        ENVIRONMENT "${MGL_ITEST_GLES_TEXTURE_UPLOAD_SHAPE_ENVIRONMENT}"
+)
+
+# --- G9: the mandatory red-before scenario -------------------------------------------
+#
+# TextureParamsWithoutASamplerViewScenario needs NO lane of its own, and that is deliberate rather
+# than an omission. It reads no counter and no log - its observable is a sampled colour - and its
+# claim is about the SHIPPING configuration, so the two ambient registrations at the top of this
+# file (which run at the build's default mask) are exactly the arms it wants. A lane here would pin
+# a mask and make the entry stop describing what ships the next time the default moved. The
+# DirectVulkan ambient entries skip in the scenario's SetUp, naming the backend: the gap it is about
+# is Espryt's SyncAttachmentObject / SyncNeccessaryTextures pair and P4a touches no DirectVulkan
+# source but MagmaPipeArms.h (D-Q).
+#
+# D-E3 expects its second case, AReadAttachmentOnlyTexturesDepthStencilModeReachesTheDriver, to be
+# RED until package esprytobj lands. MEASURED ON THE CONTRACT COMMIT IT IS GREEN, and the scenario's
+# header carries the mechanism: a texture parameter's only public-GL observable is a sample, and the
+# sample repairs the state it was meant to catch (the unit sync list re-syncs whenever the params
+# version moved). Nothing about any of that is expressed in this file - a registration that
+# "expected" a red would be a gate that could never go green - and the ruling on the missing
+# artefact is the integrator's, recorded in the gates result document.
+
 if (MOBILEGL_PIPE_VERIFY)
     # 900s, not the ambient 120: the comparator re-reads every field of the fill mask at the verb
     # boundary and again at every accessor read, which the design budgets at 5-10x.

MobileGL/MG_IntegrationTest/Harness/P4aSeamPeek.cpp

@@ -0,0 +1,107 @@
+// MobileGL - MobileGL/MG_IntegrationTest/Harness/P4aSeamPeek.cpp
+// Copyright (c) 2026 MobileGL-Dev
+// Licensed under the GNU Lesser General Public License v3.0:
+//   https://www.gnu.org/licenses/gpl-3.0.txt
+//   https://www.gnu.org/licenses/lgpl-3.0.txt
+// SPDX-License-Identifier: LGPL-3.0-only
+// End of Source File Header
+
+#include "P4aSeamPeek.h"
+
+#if !defined(__ANDROID__)
+#include <MG_Pipe/MGPipe.h>
+#if MOBILEGL_PIPE_PUSH
+#include <MG_Pipe/PipeApply.h>
+#include <MG_State/GLState/Core.h>
+#include <MG_Backend/DirectGLES/Managers.h>
+#include <MG_Backend/DirectGLES/DirectGLES.h>
+#define MGITEST_P4A_SEAM_PEEK_LIVE 1
+#endif
+#endif
+
+namespace MGITest {
+
+#if defined(MGITEST_P4A_SEAM_PEEK_LIVE)
+    namespace {
+        namespace MGP = MobileGL::MG_Pipe;
+        namespace MGB = MobileGL::MG_Backend::DirectGLES;
+
+        // "Is Espryt the backend running" - the same test PipeApplyPeek.cpp makes through a twin:
+        // on Magma no ES entry point was ever resolved and every member of g_GLESFuncs is null.
+        // It is asked BEFORE SamplerSubsystemEnabled(), which is Espryt's own latch and must not
+        // be resolved on a process whose backend is not Espryt.
+        bool EsprytIsRunning() { return MGB::g_GLESFuncs.glBindSampler != nullptr; }
+    } // namespace
+
+    bool PeekEsprytSamplerHandleArmIsLive(bool* outLive) {
+        if (outLive == nullptr) return false;
+        if (!EsprytIsRunning()) return false;
+        *outLive = MGB::SamplerSubsystemEnabled();
+        return true;
+    }
+
+    bool PeekEsprytFramebufferHandleArmIsLive(bool* outLive) {
+        if (outLive == nullptr) return false;
+        if (!EsprytIsRunning()) return false;
+        *outLive = MGB::FramebufferSubsystemEnabled();
+        return true;
+    }
+
+    bool PeekPipeShaderImageWindow(PipeShaderImageWindowPeek* out) {
+        if (out == nullptr) return false;
+        const MGP::MGPipeApplierState& applier = MGP::MGPipeApplier();
+        out->Start = static_cast<unsigned>(applier.ShaderImageStart);
+        out->Count = static_cast<unsigned>(applier.ShaderImageCount);
+        out->Serial = static_cast<unsigned long long>(applier.ShaderImagesSerial);
+        return true;
+    }
+
+    bool PeekEsprytUnitSampler(unsigned unit, unsigned glSamplerName, EsprytUnitSamplerPeek* out) {
+        if (out == nullptr) return false;
+        if (!EsprytIsRunning()) return false;
+        if (!MobileGL::MG_State::pGLContext) return false;
+        const MGP::MGPipeApplierState& applier = MGP::MGPipeApplier();
+        if (unit >= applier.BoundSamplerStates.size() || unit >= MGB::SamplerImpl::g_boundSamplersCache.size()) {
+            return false;
+        }
+        *out = EsprytUnitSamplerPeek{};
+
+        // Espryt's own binding shadow: every glBindSampler this backend issues routes through it
+        // (BackendSamplerObject::Bind / UnbindSampler), so it IS what the driver holds.
+        if (MGB::SamplerImpl::BackendSamplerObject* const bound = MGB::SamplerImpl::g_boundSamplersCache[unit]) {
+            out->BoundSamplerId = static_cast<unsigned>(bound->GetBackendSamplerId());
+        }
+
+        const MGP::MGPipeHandle cso = applier.BoundSamplerStates[unit];
+        out->CsoHandleSlot = static_cast<unsigned>(cso.Slot);
+        out->CsoHandleGen = static_cast<unsigned>(cso.Gen);
+        out->UnitInsideWindow = unit >= applier.SamplerStateStart &&
+                                unit - applier.SamplerStateStart < applier.SamplerStateCount;
+        // The twin AT THE CSO HANDLE, asked of the same table Espryt asks (FindByHandle): a null
+        // here with a live handle is the F-4 shape - a content-addressed handle looked up in a
+        // table that only ever held identity-minted slots.
+        if (!MGP::MGPipeHandleIsNull(cso)) {
+            if (auto* const slot = MGB::SamplerImpl::g_backendSamplerObjects.FindByHandle(cso); slot && *slot) {
+                out->CsoTwinSamplerId = static_cast<unsigned>((*slot)->GetBackendSamplerId());
+            }
+        }
+
+        // And the twin keyed on the frontend OBJECT, which is what the pre-handle program pass
+        // used to mint and bind, so a scenario can say which of the two the driver holds.
+        const auto& object = MobileGL::MG_State::pGLContext->GetSamplerObject(
+            static_cast<MobileGL::Uint>(glSamplerName));
+        if (object) {
+            if (auto* const slot = MGB::SamplerImpl::g_backendSamplerObjects.Find(object.get()); slot && *slot) {
+                out->IdentityTwinSamplerId = static_cast<unsigned>((*slot)->GetBackendSamplerId());
+            }
+        }
+        return true;
+    }
+#else
+    bool PeekEsprytSamplerHandleArmIsLive(bool*) { return false; }
+    bool PeekEsprytFramebufferHandleArmIsLive(bool*) { return false; }
+    bool PeekPipeShaderImageWindow(PipeShaderImageWindowPeek*) { return false; }
+    bool PeekEsprytUnitSampler(unsigned, unsigned, EsprytUnitSamplerPeek*) { return false; }
+#endif
+
+} // namespace MGITest

MobileGL/MG_IntegrationTest/Harness/P4aSeamPeek.h

@@ -0,0 +1,78 @@
+// MobileGL - MobileGL/MG_IntegrationTest/Harness/P4aSeamPeek.h
+// Copyright (c) 2026 MobileGL-Dev
+// Licensed under the GNU Lesser General Public License v3.0:
+//   https://www.gnu.org/licenses/gpl-3.0.txt
+//   https://www.gnu.org/licenses/lgpl-3.0.txt
+// SPDX-License-Identifier: LGPL-3.0-only
+// End of Source File Header
+//
+// The three readings P4aSeamAuditScenario.cpp takes from the inside, for the two seams the fable
+// seam audit proved that PUBLIC GL CANNOT SEE: F-4 (the record arm's sampler bind is a permanent
+// no-op, hidden by the pre-handle program pass binding the same values) and F-2 / SD-4 (the
+// shader-image window does not follow a program switch, hidden by the server's window/high-water
+// union taking the pre-handle bind for the units outside it). Both are correct pictures over a
+// permanent silent fallback, which is precisely the class ROADMAP.md:20 says a gate has to be
+// able to make red - and the only place the difference exists is inside.
+//
+// A SEPARATE TRANSLATION UNIT for PipeApplyPeek.h's reason, verbatim: this file includes
+// Espryt's own Managers.h, which may not meet a scenario's GL headers in one file. It is NOT
+// PipeApplyPeek.cpp because that file is package F's (gates v3) and this round may not edit it.
+//
+// EVERY ENTRY POINT RETURNS false, TOUCHING NOTHING, WHERE IT CANNOT LOOK - a pull build, Android,
+// a backend that is not Espryt - and a caller that gets false has learned NOTHING: "could not
+// look" is not "was bound". The scenario declines the reading BY NAME and keeps its public-GL
+// half, which is the shape TextureParamsWithoutASamplerViewScenario.cpp argues for.
+
+#pragma once
+
+namespace MGITest {
+
+    // ---- is Espryt's sampler family on its HANDLE arm in this process? -------------------
+    //
+    // The gate for every other reading here. True only on DirectGLES, in a push build, with
+    // Espryt's own resolver answering "handle" for kMGPipeSubsystemSamplers (bit 11 set and its
+    // dependency satisfied) - i.e. exactly when bind_sampler_states / set_shader_images are
+    // consumed, so a white-box assertion about them can be red for its own reason and for no
+    // other. Written only on true.
+    bool PeekEsprytSamplerHandleArmIsLive(bool* outLive);
+
+    // The same question for the FRAMEBUFFER family (bit 9): true when Espryt consumes
+    // set_framebuffer_state in this process. The renderbuffer half of the F-3 case asserts only
+    // there - on the pre-handle arm a renderbuffer re-storaged while attached moves nothing the
+    // FBO memo reads (D-D2's documented hole, pre-P4a code), and the record is what closes it.
+    bool PeekEsprytFramebufferHandleArmIsLive(bool* outLive);
+
+    // ---- the applier's shader-image window, as last received ------------------------------
+    //
+    // MGPipeApplierState::ShaderImageStart / ShaderImageCount / ShaderImagesSerial. Count is
+    // "how many units set_shader_images last described" - 0 means the set has NEVER arrived
+    // (MGPipeApplierReset advances the serial whether or not anything was emitted, so the serial
+    // is not that test). Push build only.
+    struct PipeShaderImageWindowPeek {
+        unsigned Start;
+        unsigned Count;
+        unsigned long long Serial;
+    };
+
+    bool PeekPipeShaderImageWindow(PipeShaderImageWindowPeek* out);
+
+    // ---- which driver sampler a texture unit is bound to, and whose twin it is -------------
+    //
+    // For F-4. `BoundSamplerId` is the ES sampler name Espryt's own binding shadow says unit
+    // `unit` carries (0 = none). `CsoHandleSlot/Gen` is bind_sampler_states' handle for the unit,
+    // `CsoTwinSamplerId` the ES name of the twin Espryt holds AT THAT HANDLE (0 = no twin at the
+    // content-addressed slot - the F-4 shape), and `IdentityTwinSamplerId` the ES name of a twin
+    // keyed on the frontend SamplerObject named `glSamplerName` (0 = none). On a correct handle
+    // arm the unit's driver sampler IS the CSO twin. Push build, DirectGLES only.
+    struct EsprytUnitSamplerPeek {
+        unsigned BoundSamplerId;
+        unsigned CsoHandleSlot;
+        unsigned CsoHandleGen;
+        bool UnitInsideWindow;
+        unsigned CsoTwinSamplerId;
+        unsigned IdentityTwinSamplerId;
+    };
+
+    bool PeekEsprytUnitSampler(unsigned unit, unsigned glSamplerName, EsprytUnitSamplerPeek* out);
+
+} // namespace MGITest

MobileGL/MG_IntegrationTest/Harness/PipeApplyPeek.cpp

@@ -0,0 +1,188 @@
+// MobileGL - MobileGL/MG_IntegrationTest/Harness/PipeApplyPeek.cpp
+// Copyright (c) 2026 MobileGL-Dev
+// Licensed under the GNU Lesser General Public License v3.0:
+//   https://www.gnu.org/licenses/gpl-3.0.txt
+//   https://www.gnu.org/licenses/lgpl-3.0.txt
+// SPDX-License-Identifier: LGPL-3.0-only
+// End of Source File Header
+
+#include "PipeApplyPeek.h"
+
+#if !defined(__ANDROID__)
+#include <MG_Pipe/MGPipe.h>
+#if MOBILEGL_PIPE_PUSH
+#include <MG_Pipe/PipeApply.h>
+#include <MG_Pipe/MGPipeTypes.h>
+#include <MG_State/GLState/Core.h>
+#include <MG_Util/Converters/MGToGL/TextureEnumConverter.h>
+#include <MG_Backend/DirectGLES/Managers.h>
+#include <MG_Backend/DirectGLES/DirectGLES.h>
+#define MGITEST_PIPE_APPLY_PEEK_LIVE 1
+#endif
+#endif
+
+namespace MGITest {
+
+#if defined(MGITEST_PIPE_APPLY_PEEK_LIVE)
+    namespace {
+        namespace MGP = MobileGL::MG_Pipe;
+        namespace MGB = MobileGL::MG_Backend::DirectGLES;
+
+        // The frontend texture object a GL name denotes in the CURRENT context, or null. This is
+        // a LOOKUP KEY and nothing else: every value this file reports comes from the applier or
+        // from Espryt, never from the object found here. (Reading the frontend's own parameter
+        // state would answer the question the scenario is asking with the input to it.)
+        MobileGL::MG_State::GLState::ITextureObject* FrontendTexture(unsigned glTextureName) {
+            if (!MobileGL::MG_State::pGLContext) return nullptr;
+            const auto& object = MobileGL::MG_State::pGLContext->GetTextureObject(
+                static_cast<MobileGL::Uint>(glTextureName));
+            return object ? object.get() : nullptr;
+        }
+
+        // Espryt's twin for that texture, or null - which is also this file's "is Espryt even the
+        // backend running" answer. On Magma no Espryt twin was ever built, so every entry point
+        // below stops here rather than reaching for g_GLESFuncs, whose members are null there.
+        MGB::TextureImpl::BackendTextureObject* EsprytTwin(unsigned glTextureName) {
+            MobileGL::MG_State::GLState::ITextureObject* const object = FrontendTexture(glTextureName);
+            if (object == nullptr) return nullptr;
+            auto* const found = MGB::TextureImpl::g_backendTextureObjects.Find(object);
+            if (found == nullptr || !*found) return nullptr;
+            return found->get();
+        }
+
+        int SwizzleToGLEnum(MobileGL::Uint8 encoded) {
+            return static_cast<int>(MobileGL::MG_Util::ConvertTextureSwizzleParamToGLEnum(
+                static_cast<MobileGL::TextureSwizzleParam>(encoded)));
+        }
+
+        // MGPipeTypes.h owns the two numbers and says why depth is 0 (a zeroed record must decode
+        // to what an untouched texture already has). This is that decode, and nothing else in
+        // this module may open-code it.
+        int DepthStencilModeToGLEnum(MobileGL::Uint8 encoded) {
+            return encoded == MGP::kMGPipeDepthStencilModeStencil ? GL_STENCIL_INDEX
+                                                                  : GL_DEPTH_COMPONENT;
+        }
+
+        // The GL_TEXTURE_BINDING_* query for a target, or 0 where this file has no answer. A
+        // guess would be worse than a refusal: the binding is what gets RESTORED, so a wrong
+        // pname would leave the driver bound to this test's texture.
+        int BindingQueryFor(unsigned glTarget) {
+            switch (glTarget) {
+                case GL_TEXTURE_2D: return GL_TEXTURE_BINDING_2D;
+                default: return 0;
+            }
+        }
+    } // namespace
+
+    bool PeekPipeTextureParamsRecord(unsigned glTextureName, PipeTextureParamsRecordPeek* out) {
+        if (out == nullptr) return false;
+        const MGP::MGPipeApplierState& applier = MGP::MGPipeApplier();
+        // Slot 0 is the reserved null handle and is never live (MGPipeHandles.h), so the scan
+        // starts at 1 and a match at 0 is impossible rather than merely unlikely.
+        for (MobileGL::SizeT slot = 1; slot < applier.TextureResources.size(); ++slot) {
+            const MGP::MGPipeResourceRecord& record = applier.TextureResources[slot];
+            if (!record.Live) continue;
+            if (record.Desc.GlNameForDiag != static_cast<MobileGL::Uint32>(glTextureName)) continue;
+            out->Slot = static_cast<unsigned>(slot);
+            out->Gen = static_cast<unsigned>(record.Gen);
+            out->ParamsSerial = static_cast<unsigned long long>(record.ParamsSerial);
+            for (int channel = 0; channel < 4; ++channel) {
+                out->Swizzle[channel] = SwizzleToGLEnum(record.Params.Swizzle[channel]);
+            }
+            out->DepthStencilMode = DepthStencilModeToGLEnum(record.Params.DepthStencilMode);
+            return true;
+        }
+        return false;
+    }
+
+    bool PeekEsprytAppliedTextureParams(unsigned glTextureName, unsigned glTarget,
+                                        EsprytAppliedTextureParamsPeek* out) {
+        if (out == nullptr) return false;
+        const int bindingQuery = BindingQueryFor(glTarget);
+        if (bindingQuery == 0) return false;
+        MGB::TextureImpl::BackendTextureObject* const twin = EsprytTwin(glTextureName);
+        if (twin == nullptr) return false;
+        const MobileGL::Uint backendId = twin->GetBackendTextureId();
+        if (backendId == 0) return false;
+        if (MGB::g_GLESFuncs.glGetTexParameteriv == nullptr ||
+            MGB::g_GLESFuncs.glBindTexture == nullptr || MGB::g_GLESFuncs.glGetIntegerv == nullptr ||
+            MGB::g_GLESFuncs.glGetError == nullptr) {
+            return false;
+        }
+
+        // SAVE / QUERY / RESTORE ON THE UNIT THAT IS ALREADY ACTIVE. No glActiveTexture, so the
+        // only driver state this touches is one unit's binding, and it is put back byte for byte
+        // - which is what keeps Espryt's own g_boundTexturesCache true rather than merely
+        // consistent. (Binding through the twin's own Bind() would update that shadow and would
+        // therefore CHANGE what the scenario measures next; this does not.)
+        GLint previousBinding = 0;
+        MGB::g_GLESFuncs.glGetIntegerv(static_cast<GLenum>(bindingQuery), &previousBinding);
+        MGB::g_GLESFuncs.glBindTexture(static_cast<GLenum>(glTarget), backendId);
+
+        out->BackendTextureId = static_cast<unsigned>(backendId);
+        static const GLenum kSwizzlePnames[4] = {GL_TEXTURE_SWIZZLE_R, GL_TEXTURE_SWIZZLE_G,
+                                                 GL_TEXTURE_SWIZZLE_B, GL_TEXTURE_SWIZZLE_A};
+        for (int channel = 0; channel < 4; ++channel) {
+            GLint value = 0;
+            MGB::g_GLESFuncs.glGetTexParameteriv(static_cast<GLenum>(glTarget),
+                                                 kSwizzlePnames[channel], &value);
+            out->Swizzle[channel] = static_cast<int>(value);
+        }
+
+        // The depth/stencil aspect mode is ES 3.1 and is INVALID_ENUM on a driver without it, so
+        // it is asked for last and its own error decides whether the answer is usable. The queue
+        // is drained first because a stale error from anywhere else would be indistinguishable
+        // from this call's - Espryt drains it the same way at every one of its own sync sites
+        // (DebugImpl::ErrorLopper), and this module's own GL errors are read from the FRONTEND
+        // state (ScenarioTest::FirstGLError), which none of this touches.
+        while (MGB::g_GLESFuncs.glGetError() != GL_NO_ERROR) {
+        }
+        GLint mode = 0;
+        MGB::g_GLESFuncs.glGetTexParameteriv(static_cast<GLenum>(glTarget),
+                                             GL_DEPTH_STENCIL_TEXTURE_MODE, &mode);
+        out->DepthStencilModeIsReadable = MGB::g_GLESFuncs.glGetError() == GL_NO_ERROR;
+        out->DepthStencilMode = static_cast<int>(mode);
+
+        MGB::g_GLESFuncs.glBindTexture(static_cast<GLenum>(glTarget),
+                                       static_cast<GLuint>(previousBinding));
+        while (MGB::g_GLESFuncs.glGetError() != GL_NO_ERROR) {
+        }
+        return true;
+    }
+
+    bool PeekEsprytHasSamplerViewForTexture(unsigned glTextureName, bool* outExists) {
+        if (outExists == nullptr) return false;
+        MobileGL::MG_State::GLState::ITextureObject* const object = FrontendTexture(glTextureName);
+        if (object == nullptr) return false;
+        // Espryt must be the backend running, or "no view" would be true of every texture on
+        // every other backend and the assertion would be vacuous where it is loudest.
+        if (EsprytTwin(glTextureName) == nullptr) return false;
+        // HandleOfSamplerViewForTexture is the monolith glue that derives the view's handle from
+        // the TEXTURE's lifetime id (D-F2: one view per ITextureObject), so this asks Espryt's
+        // own table the same way Espryt asks it - it does not consult the applier record's
+        // ViewCso, which is the client's statement about the same fact and would make one side
+        // of the seam vouch for the other.
+        const MGP::MGPipeHandle view = MGB::SamplerViewImpl::HandleOfSamplerViewForTexture(object);
+        if (MGP::MGPipeHandleIsNull(view)) {
+            *outExists = false;
+            return true;
+        }
+        *outExists = MGB::SamplerViewImpl::FindSamplerViewForHandle(view) != nullptr;
+        return true;
+    }
+
+    bool PeekPipeApplierRefusedNoConsumer(unsigned long long* outCount) {
+        if (outCount == nullptr) return false;
+        *outCount = static_cast<unsigned long long>(MGP::MGPipeApplier().RefusedNoConsumer);
+        return true;
+    }
+#else
+    bool PeekPipeTextureParamsRecord(unsigned, PipeTextureParamsRecordPeek*) { return false; }
+    bool PeekEsprytAppliedTextureParams(unsigned, unsigned, EsprytAppliedTextureParamsPeek*) {
+        return false;
+    }
+    bool PeekEsprytHasSamplerViewForTexture(unsigned, bool*) { return false; }
+    bool PeekPipeApplierRefusedNoConsumer(unsigned long long*) { return false; }
+#endif
+
+} // namespace MGITest

MobileGL/MG_IntegrationTest/Harness/PipeApplyPeek.h

@@ -0,0 +1,110 @@
+// MobileGL - MobileGL/MG_IntegrationTest/Harness/PipeApplyPeek.h
+// Copyright (c) 2026 MobileGL-Dev
+// Licensed under the GNU Lesser General Public License v3.0:
+//   https://www.gnu.org/licenses/gpl-3.0.txt
+//   https://www.gnu.org/licenses/lgpl-3.0.txt
+// SPDX-License-Identifier: LGPL-3.0-only
+// End of Source File Header
+//
+// The APPLIER's texture-parameter record, ESPRYT's applied value for the same texture, and
+// whether that texture has a sampler view yet. Three readings taken from a scenario, for gate
+// G9's WHITE-BOX half.
+//
+// WHY A WHITE-BOX HALF EXISTS AT ALL (ID-19, brief section F, gates review R1). G9's public-GL
+// cases in TextureParamsWithoutASamplerViewScenario.cpp catch "the parameter never reached the
+// driver". They CANNOT catch "the parameter reached the driver LATE", because a texture
+// parameter's only public-GL observable is a SAMPLE and the sample is itself what repairs an
+// unsynced parameter: it puts the texture on the unit list, and that walk pushes the parameters
+// for anything whose params serial moved. A backend that deferred every attachment-only
+// texture's parameters to the first sampler view would be green on all four of those cases,
+// forever, on every tree. The distinction only exists on the inside, so the reading has to be
+// taken there - while the texture is still attachment-only, before any sample.
+//
+// A SEPARATE TRANSLATION UNIT for PipeSlotPeek.h's reason, verbatim: the scenario sources
+// include the GL headers with prototypes and MobileGL's umbrella header is not meant to meet
+// them in one file. This one goes further than PipeSlotPeek and includes Espryt's own
+// Managers.h, which is exactly why it may not be anywhere near a scenario's GL headers.
+//
+// EVERY ENTRY POINT RETURNS false, TOUCHING NOTHING, WHERE IT CANNOT LOOK, and a caller that
+// gets false has learned NOTHING - "could not look" is not "was applied". Out of reach means:
+// a PULL build (there is no applier: it is `#if MOBILEGL_PIPE_PUSH`); Android, where this module
+// links the shipping libMobileGL.so built -fvisibility=hidden and no internal symbol resolves;
+// a backend that is not DirectGLES (Espryt is the subject; Magma answers the same GL question
+// through P7's own paths); and, for the record peek, a mask whose texture-resource bit is off,
+// where no record exists to find because nothing was ever emitted.
+
+#pragma once
+
+namespace MGITest {
+
+    // ---- the applier's set_texture_params record for one GL texture name ------------------
+    //
+    // ADDRESSED BY GL NAME, and the search key is MGPResourceDesc::GlNameForDiag. That field is
+    // diagnostics-only by contract - never an identity, never a memo key (MGPipeTypes.h) - and
+    // this is a diagnostic: a test harness looking for the record a named GL object produced.
+    // The alternative would be to ask the CLIENT emitter for the texture's handle, and the
+    // review is explicit that this probe must arm on package D's applier/backend state and not
+    // on the emitter markers B and C set: they are different questions, and a shared marker
+    // would re-create the shape review F-M5 was raised about.
+    struct PipeTextureParamsRecordPeek {
+        // The handle the record sits at, so a caller can print it.
+        unsigned Slot;
+        unsigned Gen;
+        // set_texture_params' own serial. 0 means the record exists (the resource was created)
+        // but NO set_texture_params has ever been applied to it - which is a different finding
+        // from "no record", and the two must not be merged.
+        unsigned long long ParamsSerial;
+        // MGPTextureParams::Swizzle[4], translated to the GL enums the application passed to
+        // glTextureParameteri (GL_ZERO / GL_ONE / GL_RED / GL_GREEN / GL_BLUE / GL_ALPHA), so
+        // the scenario compares what it set against what the record carries in ONE vocabulary
+        // and neither side has to know the other's encoding.
+        int Swizzle[4];
+        // MGPTextureParams::DepthStencilMode, translated the same way: GL_DEPTH_COMPONENT or
+        // GL_STENCIL_INDEX.
+        int DepthStencilMode;
+    };
+
+    bool PeekPipeTextureParamsRecord(unsigned glTextureName, PipeTextureParamsRecordPeek* out);
+
+    // ---- Espryt's APPLIED value for the same texture --------------------------------------
+    //
+    // Read from the DRIVER, through the twin's own ES name, because "applied" means the driver
+    // was told - the same thing package D's white-box unit probe asserts against its mocked
+    // driver (esprytobj-v2 (9)). The current binding on the ACTIVE unit is saved and restored
+    // around the query and no unit is switched, so Espryt's binding shadow still describes
+    // reality afterwards: nothing is perturbed for it to be stale about.
+    //
+    // `glTarget` is the texture's GL target (only GL_TEXTURE_2D is supported today; any other
+    // target returns false rather than guessing a binding query).
+    struct EsprytAppliedTextureParamsPeek {
+        // The driver name Espryt minted for this texture, for the caller's message.
+        unsigned BackendTextureId;
+        int Swizzle[4];
+        int DepthStencilMode;
+        // False when the driver rejected the depth/stencil query - a non-depth texture, or an ES
+        // level without GL_DEPTH_STENCIL_TEXTURE_MODE. The swizzle half is still valid.
+        bool DepthStencilModeIsReadable;
+    };
+
+    bool PeekEsprytAppliedTextureParams(unsigned glTextureName, unsigned glTarget,
+                                        EsprytAppliedTextureParamsPeek* out);
+
+    // ---- and the claim that makes the two above mean anything ------------------------------
+    //
+    // Whether Espryt holds a SAMPLER VIEW twin for this texture. This is the assertion the
+    // public-GL cases cannot make, because making it there would create the view. `*outExists`
+    // is written only on true.
+    bool PeekEsprytHasSamplerViewForTexture(unsigned glTextureName, bool* outExists);
+
+    // ---- c0f's belt, for the ObjectSubsystemControl arms -----------------------------------
+    //
+    // MGPipeApplierState::RefusedNoConsumer: the number of P4a-family entry points that were
+    // refused because no backend had registered MGPipeResourceOps. On a backend WITH a consumer
+    // it must never move; on one without (Magma, ID-39/ID-40) the client's own gate is supposed
+    // to stop the emission before the belt is reached, so it must never move there either. A
+    // non-zero delta says the gate and the belt disagreed, which is the whole point of having
+    // both. Reset by MGPipeApplierReset, so a caller reads it as a DELTA and treats a value that
+    // went DOWN as "the applier was reset, count everything since as `after`".
+    bool PeekPipeApplierRefusedNoConsumer(unsigned long long* outCount);
+
+} // namespace MGITest

MobileGL/MG_IntegrationTest/Harness/PipeSlotPeek.cpp

@@ -20,11 +20,24 @@ namespace MGITest {
 
 #if defined(MGITEST_PIPE_SLOT_PEEK_LIVE)
     namespace {
+        // One arm per member, and NO `default:` on purpose: adding a PipeSlotKind without
+        // deciding which MGPipeKind it names is a compiler warning here (-Wswitch) rather than
+        // a row that silently counts VertexElementsCso and reports "did not leak" about a kind
+        // it never looked at. The trailing return is the unreachable one the compiler needs.
         MobileGL::MG_Pipe::MGPipeKind Translate(PipeSlotKind kind) {
             switch (kind) {
                 case PipeSlotKind::Buffer: return MobileGL::MG_Pipe::MGPipeKind::Buffer;
-                default: return MobileGL::MG_Pipe::MGPipeKind::VertexElementsCso;
+                case PipeSlotKind::VertexElementsCso:
+                    return MobileGL::MG_Pipe::MGPipeKind::VertexElementsCso;
+                case PipeSlotKind::Texture: return MobileGL::MG_Pipe::MGPipeKind::Texture;
+                case PipeSlotKind::Renderbuffer: return MobileGL::MG_Pipe::MGPipeKind::Renderbuffer;
+                case PipeSlotKind::Framebuffer: return MobileGL::MG_Pipe::MGPipeKind::Framebuffer;
+                case PipeSlotKind::SamplerCso: return MobileGL::MG_Pipe::MGPipeKind::SamplerCso;
+                case PipeSlotKind::SamplerViewCso:
+                    return MobileGL::MG_Pipe::MGPipeKind::SamplerViewCso;
+                case PipeSlotKind::ShaderCso: return MobileGL::MG_Pipe::MGPipeKind::ShaderCso;
             }
+            return MobileGL::MG_Pipe::MGPipeKind::None;
         }
     } // namespace
 
@@ -36,12 +49,34 @@ namespace MGITest {
 
     bool PeekPipeSlotHighWater(PipeSlotKind kind, unsigned* outHighWater) {
         if (outHighWater == nullptr) return false;
+        // The ORDINARY space only, for every kind including ShaderCso (contract-v2.md 4.3).
         *outHighWater = static_cast<unsigned>(MobileGL::MG_Pipe::MGPipeSlots().HighWater(Translate(kind)));
         return true;
     }
+
+    bool PeekPipeCompositeSlotLiveCount(unsigned* outLive) {
+        if (outLive == nullptr) return false;
+        *outLive = static_cast<unsigned>(MobileGL::MG_Pipe::MGPipeSlots().CompositeLiveCount());
+        return true;
+    }
+
+    bool PeekPipeCompositeSlotHighWater(unsigned* outHighWater) {
+        if (outHighWater == nullptr) return false;
+        *outHighWater = static_cast<unsigned>(MobileGL::MG_Pipe::MGPipeSlots().CompositeHighWater());
+        return true;
+    }
+
+    bool PeekPipeCompositeSlotBandBase(unsigned* outBandBase) {
+        if (outBandBase == nullptr) return false;
+        *outBandBase = static_cast<unsigned>(MobileGL::MG_Pipe::kMGPipeShaderCsoCompositeSlotBase);
+        return true;
+    }
 #else
     bool PeekPipeSlotLiveCount(PipeSlotKind, unsigned*) { return false; }
     bool PeekPipeSlotHighWater(PipeSlotKind, unsigned*) { return false; }
+    bool PeekPipeCompositeSlotLiveCount(unsigned*) { return false; }
+    bool PeekPipeCompositeSlotHighWater(unsigned*) { return false; }
+    bool PeekPipeCompositeSlotBandBase(unsigned*) { return false; }
 #endif
 
 } // namespace MGITest

MobileGL/MG_IntegrationTest/Harness/PipeSlotPeek.h

@@ -30,6 +30,36 @@ namespace MGITest {
     enum class PipeSlotKind {
         Buffer,
         VertexElementsCso,
+        // P4a's six (G8b). Every one of them is a kind the CLIENT mints and the client alone
+        // frees (BRIEF-P4A.md D-I1: one death helper per kind, called from the frontend
+        // object's own destructor, whatever backend is running), so every one of them can leak
+        // the P3a C-1 way - and the leak is invisible in pixels, in GL names and in
+        // glGetError, exactly as the VertexElementsCso one was.
+        Texture,
+        Renderbuffer,
+        // Framebuffer has a HANDLE but no wire lifetime (D-I2): no create_*, no destroy row in
+        // the catalogue, and its death helper does the notice and the free and emits nothing.
+        // That makes the allocator the ONLY observable of its lifetime, so this row matters
+        // more here than the others rather than less.
+        Framebuffer,
+        SamplerCso,
+        SamplerViewCso,
+        // ShaderCso covers BOTH the ordinary program slots and the program-pipeline COMPOSITES
+        // minted out of the reserved high band (MGPipeHandles.h:86-107, D-H7). One kind, because
+        // that is what the allocator has: the band is a second dense table inside the same kind
+        // and LiveCount counts both.
+        //
+        // THE TWO SPACES' HIGH-WATER MARKS ARE NOT ONE NUMBER, and the correction matters here
+        // more than anywhere else. c0b split them (contract-v2.md 4.3): HighWater(ShaderCso) is
+        // now the ORDINARY space only and the band's own mark is CompositeHighWater(), because
+        // a merged mark is pinned at ~983k from the first composite mint onward and every "the
+        // high-water mark did not move over N churn rounds" assertion about ordinary programs
+        // would be vacuously true for the rest of the process. The composite's leak case is a
+        // separate CASE and reads the BAND'S OWN counters below (PeekPipeCompositeSlot*) - a
+        // composite's slot has TWO independent release paths (the pipeline cache's LRU eviction
+        // and the composite ProgramObject's destructor), and a slot that never comes back to
+        // the band moves neither of the ordinary numbers.
+        ShaderCso,
     };
 
     // Live slots of this kind right now, and one past the highest slot ever handed out.
@@ -41,4 +71,31 @@ namespace MGITest {
     bool PeekPipeSlotLiveCount(PipeSlotKind kind, unsigned* outLive);
     bool PeekPipeSlotHighWater(PipeSlotKind kind, unsigned* outHighWater);
 
+    // The ShaderCso COMPOSITE BAND's own three numbers, the seventh..ninth members
+    // contract-v2.md 4.3 asks this header for. There is no `kind` argument because the band is
+    // ShaderCso's alone - AllocateComposite is the one door into it and no other kind has one.
+    // All three return false on the same terms as the two above, and a caller that gets false
+    // must SKIP.
+    //
+    //   PeekPipeCompositeSlotLiveCount   = MGPipeSlotAllocator::CompositeLiveCount(), the band's
+    //                                      share of LiveCount(ShaderCso).
+    //   PeekPipeCompositeSlotHighWater   = CompositeHighWater() VERBATIM, i.e. one past the
+    //                                      highest band slot ever handed out. It is an ABSOLUTE
+    //                                      slot number and therefore starts at the band's base,
+    //                                      not at zero - "no composite was ever minted" reads as
+    //                                      `high water == band base`, which is what the third
+    //                                      member is for. It is not returned base-relative
+    //                                      because a peek whose name says HighWater and whose
+    //                                      value is a delta is exactly the kind of quietly
+    //                                      redefined counter this member exists to correct.
+    //   PeekPipeCompositeSlotBandBase    = kMGPipeShaderCsoCompositeSlotBase, the floor the
+    //                                      other two are read against. A constant, but it
+    //                                      reaches a scenario only through this header: the
+    //                                      MG_Pipe headers and the GL headers are not meant to
+    //                                      meet in one translation unit, which is why this
+    //                                      harness exists at all.
+    bool PeekPipeCompositeSlotLiveCount(unsigned* outLive);
+    bool PeekPipeCompositeSlotHighWater(unsigned* outHighWater);
+    bool PeekPipeCompositeSlotBandBase(unsigned* outBandBase);
+
 } // namespace MGITest

MobileGL/MG_IntegrationTest/Scenarios/ObjectSubsystemControlScenario.cpp

@@ -0,0 +1,878 @@
+// MobileGL - MobileGL/MG_IntegrationTest/Scenarios/ObjectSubsystemControlScenario.cpp
+// Copyright (c) 2026 MobileGL-Dev
+// Licensed under the GNU Lesser General Public License v3.0:
+//   https://www.gnu.org/licenses/gpl-3.0.txt
+//   https://www.gnu.org/licenses/lgpl-3.0.txt
+// SPDX-License-Identifier: LGPL-3.0-only
+// End of Source File Header
+//
+// Scenario - THE P4a SUBSYSTEM A/B IS REAL, AND ITS DEPENDENCY REFUSALS ARE EXERCISED (gate G12).
+//
+// P4a migrates FOUR subsystems (D-K1, MG_Pipe/MGPipe.h):
+//
+//   bit  9  kMGPipeSubsystemFramebuffer       set_framebuffer_state
+//   bit 10  kMGPipeSubsystemTextureResources  texture + renderbuffer resource_*, set_texture_params
+//   bit 11  kMGPipeSubsystemSamplers          sampler CSO, sampler view, the three unit sets
+//   bit 12  kMGPipeSubsystemPrograms          shader CSO, draw/dispatch program, global constants
+//
+// so the push build's default mask becomes kMGPipeSubsystemsMigratedAtP4a = 0x1fff, and P3a's
+// 0x1ff survives as the control that clears exactly those four - MGPipe.h's rule that every phase's
+// constant keeps meaning what it meant, so an operator's recorded mask is still readable a phase
+// later. THE OFF LANE IS 0x1ff AND NOT A HAND-PICKED PATTERN, for that reason.
+//
+// That A/B is what every "push vs pull" number in MEASUREMENTS.md is taken against, and it has one
+// characteristic failure mode: the bits stop steering anything, both arms run the same code, and
+// every later comparison is quietly taken against a switch that does nothing. This file is the
+// entry that cannot let that happen. It is the P4a analogue of ResourceSubsystemControlScenario and
+// deliberately its twin in shape.
+//
+// WHAT IT ASSERTS, per lane:
+//
+//   on  (MOBILEGL_PIPE_PUSH=0x1fff)
+//       The client emits P4a's records for the workload: a framebuffer state per bound target that
+//       moved, the three unit sets, and the client-side texture upload record. The window's
+//       emit[fbe= sve= sse= sie= ctu=] bracket therefore carries a NON-ZERO total.
+//
+//   off (MOBILEGL_PIPE_PUSH=0x1ff, P3a's default = P4a's four subsystems cleared)
+//       The frontend dispatch falls through to the legacy MGB_CTX-reading arms, nothing is emitted
+//       through any of the four families, and every one of those five counters must read ZERO.
+//       This is the reading a dead switch fails: with the bits ignored, this lane would report the
+//       same non-zero counts as the other one.
+//
+//   refused (MOBILEGL_PIPE_PUSH=0x9ff = bits 0..8 plus bit 11, samplers, WITHOUT bit 10)
+//       D-K2's dependency refusal. Every MGPBoundView::Texture and MGPImageView::Res names a
+//       Texture handle and only bit 10 populates the texture slot table, so a sampler subsystem
+//       without it would miss every lookup and walk on without unbinding. The bring-up logs ONE
+//       error naming BOTH bits, refuses bit 11 and runs the legacy sampler arm - modelled on the
+//       bit-8-requires-bit-7 refusal that already ships (Managers.cpp:2393-2410). The assertion is
+//       that the refusal is NAMED and that the run then produces the same pixels as any other
+//       lane: a refusal that half-ran, or that aborted, would both be failures here.
+//
+//   refused-texture (MOBILEGL_PIPE_PUSH=0x5ff = bits 0..8 plus bit 10, texture resources, WITHOUT
+//       bit 11)
+//       D-K2's FOURTH row (ID-15), and the direction the brief originally called harmless.
+//       MGPTextureParams::BuiltinSampler is a SamplerCso HANDLE and only bit 11 mints sampler
+//       CSOs, so with bit 10 alone every set_texture_params would carry a null there and the
+//       applier's Fatal{ProtocolCorruption} is the next thing that happens. Same two assertions
+//       as the lane above, with the two bits' roles swapped.
+//
+//   both refusal lanes
+//       "NAMED" means ONE LINE of the library's log, at ERROR severity, that says it REFUSED and
+//       names both bits. Not a substring anywhere in the file: the word "sampler" appears in
+//       almost any log the sampler path writes to, and an assertion that cannot go red for its
+//       stated reason is worse than no assertion (review F-M6).
+//
+//   every lane
+//       THE PIXELS MUST NOT MOVE. The workload draws one solid-colour quad through a texture, an
+//       explicit sampler object and a user framebuffer, and every lane must read back that colour.
+//       "The counters moved and the picture did not" is the whole claim - a switch that changed
+//       what is drawn would not be an A/B, it would be a bug.
+//
+// WHY IT CAN SKIP. The counters are emitted by the client-side emitters P4a packages B and C own,
+// and this file is written against the P4a contract commit, before either lands. Until then nothing
+// emits, the five counters are structurally zero in BOTH lanes, and an assertion about the
+// difference would be a statement about nothing. The build answers the question rather than a
+// hand-maintained list: MG_IntegrationTest/CMakeLists.txt greps every source under MG_Impl/Pipe/
+// for the counters' names and passes the answer in as MGITEST_PIPE_OBJECT_EMITTER_PRESENT, with a
+// CONFIGURE_DEPENDS on that directory and on each file it finds so the answer cannot go stale. It
+// is a CONTENT probe, not a filename probe, so the owning packages keep control of their own file
+// layout - P4a's new client files are headers (D-P), and a glob for a named .cpp would have kept
+// this control skipping forever with a reason that had become false.
+//
+// DIRECTGLES ONLY, and that is the honest scope: P4a migrates Espryt's framebuffer, texture,
+// sampler and program paths. Magma's are P7 (D-Q) and register nothing here, so a DirectVulkan lane
+// would be measuring the client emitters against a backend nobody asked to change.
+
+#include <cstdint>
+#include <cstdlib>
+#include <cstring>
+#include <iostream>
+#include <string>
+#include <vector>
+
+#include "../Harness/HeadlessGL.h"
+#include "../Harness/PipeApplyPeek.h"
+#include "../Harness/PipeStatsWindow.h"
+#include "../Harness/ScenarioFixture.h"
+
+#ifdef GLAPI
+#undef GLAPI
+#endif
+#define GL_GLEXT_PROTOTYPES
+#include <GL/gl.h>
+#include <GL/glcorearb.h>
+#undef GL_GLEXT_PROTOTYPES
+
+namespace MGITest {
+    namespace {
+
+        // Set by the three ObjectSubsystemControl. ctest entries and by nothing else; a harness
+        // marker, never read by the library. Its absence means an ambient entry, where neither the
+        // stats channel nor a private log path is configured.
+        constexpr const char* kLaneMarker = "MGITEST_OBJECT_SUBSYSTEM_LANE";
+        constexpr const char* kLaneOn = "on";
+        constexpr const char* kLaneOff = "off";
+        constexpr const char* kLaneRefused = "refused";
+        // D-K2's FOURTH row (ID-15): bit 10 without bit 11. 0x5ff is 0x1ff plus bit 10.
+        constexpr const char* kLaneRefusedTexture = "refused-texture";
+        // c0f's two halves (ID-39/ID-40), run at the phase default on BOTH backends: the client
+        // GATE (a P4a family emits only where a backend registered MGPipeResourceOps) and the
+        // applier's BELT (every P4a entry point refuses and counts RefusedNoConsumer when none
+        // did). One lane per backend, because the interesting one is the backend with NO
+        // consumer - Magma - and the other is the control that says the assertion is not
+        // vacuously true of a tree where nothing emits at all.
+        constexpr const char* kLaneConsumer = "consumer";
+        constexpr const char* kLaneNoConsumer = "no-consumer";
+
+        bool LaneIsARefusalLane(const std::string& lane) {
+            return lane == kLaneRefused || lane == kLaneRefusedTexture;
+        }
+
+        bool LaneIsAConsumerLane(const std::string& lane) {
+            return lane == kLaneConsumer || lane == kLaneNoConsumer;
+        }
+
+        constexpr int kInset = 2;
+        constexpr int kTextureSize = 4;
+        // Enough frames that a per-frame emitter and a per-draw emitter read differently, and few
+        // enough that one summary window covers exactly this.
+        constexpr int kDrawsInTheWindow = 4;
+
+        constexpr const char* kVS = R"(#version 330 core
+in vec2 aPos;
+out vec2 vUv;
+void main() {
+    vUv = aPos * 0.5 + 0.5;
+    gl_Position = vec4(aPos, 0.0, 1.0);
+}
+)";
+
+        constexpr const char* kFS = R"(#version 330 core
+in vec2 vUv;
+uniform sampler2D uTex;
+out vec4 oColor;
+void main() { oColor = texture(uTex, vUv); }
+)";
+
+        struct Vertex {
+            float x, y;
+        };
+
+        bool BuildMarkerIsSet(const char* name) {
+            const char* value = std::getenv(name);
+            return value != nullptr && value[0] == '1' && value[1] == '\0';
+        }
+
+        std::string LaneName() {
+            const char* lane = std::getenv(kLaneMarker);
+            return lane != nullptr ? std::string(lane) : std::string();
+        }
+
+        // ---- reading the refusal out of the library's own log ------------------------------
+        //
+        // THE UNIT IS A LINE, AND THE LINE HAS TO BE THE REFUSAL (review F-M6). The first cut of
+        // this asked whether the WHOLE FILE contained a lowercase "sampler" and whether it
+        // contained "texture resource", anywhere, in any order, at any severity. Both are true of
+        // almost any log the moment the sampler path says anything at all, so the assertion could
+        // not go red for the reason it claims and the one P4a control that is not vacuous before
+        // the emitters land would have been vacuous too.
+        //
+        // What is matched instead is one line that is ALL of:
+        //   * at ERROR severity - the library writes "[<time>] [<os> <thread>/<TAG>]: <message>",
+        //     one record per line (MG_Util/Debug/Log.cpp), and D-K2 asks for an MGLOG_E. A refusal
+        //     that was demoted to a D or a W is a refusal an operator's log will not carry;
+        //   * carrying the helper's own decision clause, verbatim - so a line that merely
+        //     mentions the two bits (a future summary, a comment echoed into the log) is not
+        //     mistaken for the decision;
+        //   * naming the bit that was SET and the bit it NEEDED, on that same line, AND IN THAT
+        //     ORDER - see the direction check below.
+        //
+        // Espryt's text is one MGLOG_E from the helper the three dependent families share
+        // (Managers.cpp, PipeSubsystemDependencyMissing): "MGPipe: <A> (bit N) is set but <B>
+        // (bit M) is clear; <why> - REFUSING the dependent bit and running the legacy arm. Set
+        // both bits, or clear both". Three spellings are accepted per bit - the constant's name,
+        // "(bit N)", and the hexadecimal mask - so the assertion pins the DECISION and the
+        // DIRECTION, and not the family-specific prose in <why>.
+        //
+        // THE DIRECTION IS THE HALF THIS FILE USED TO BE MISSING (review F-v2-m1). The first form
+        // of the matcher asked "does the line name bit A?" AND "does the line name bit B?", which
+        // is a SYMMETRIC conjunction: swapping the two arguments - exactly what separates the
+        // 0x5ff case from the 0x9ff one below, and what each of their comments claims to be
+        // doing - could not change the answer, and both cases went green on either line. A
+        // resolver that refused correctly but printed the MIRROR sentence would have been green
+        // on a refusal that told the operator the wrong dependency, which is the same class of
+        // "the log says something plausible" defect that made the whole-file substring search
+        // (F-M6) worthless one level up. The two resolvers are forty lines apart in one file,
+        // share this helper and differ only in the `what` string, so the copy-paste is one edit
+        // away at all times.
+        //
+        // What makes the direction readable is the sentence's own shape: the SET bit is named
+        // before " is set but " and the NEEDED bit between that and " is clear". So the check is
+        // four offsets in strictly increasing order, and it is the sentence Espryt emits rather
+        // than a re-statement of it.
+        constexpr const char* kSaysItRefused = "REFUSING the dependent bit and running the legacy arm";
+        constexpr const char* kSaysWhichIsSet = " is set but ";
+        constexpr const char* kSaysWhichIsClear = " is clear";
+
+        // The earliest offset at which any accepted spelling of one bit appears, or npos. The
+        // EARLIEST rather than any: a spelling that also occurs later in <why> (Espryt's
+        // bit-10-requires-bit-11 sentence says "only bit 11 mints sampler CSOs" in its reason)
+        // must not be able to satisfy an ordering the first occurrence does not.
+        std::size_t EarliestSpellingOffset(const std::string& line,
+                                           const std::vector<std::string>& spellings) {
+            std::size_t earliest = std::string::npos;
+            for (const std::string& spelling : spellings) {
+                const std::size_t at = line.find(spelling);
+                if (at != std::string::npos && (earliest == std::string::npos || at < earliest)) {
+                    earliest = at;
+                }
+            }
+            return earliest;
+        }
+
+        // The matching line, or an empty string. Returned rather than a bool so the case can print
+        // what it found: a reader of a green refusal lane must be able to see the sentence.
+        std::string FindTheRefusalLine(const std::string& log,
+                                       const std::vector<std::string>& bitThatWasSet,
+                                       const std::vector<std::string>& bitThatWasNeeded) {
+            std::size_t pos = 0;
+            while (pos <= log.size()) {
+                const std::size_t newline = log.find('\n', pos);
+                const std::string line = log.substr(
+                    pos, newline == std::string::npos ? std::string::npos : newline - pos);
+                const bool atErrorSeverity = line.find("/ERROR]") != std::string::npos;
+                const std::size_t refusedAt = line.find(kSaysItRefused);
+                const std::size_t setAt = EarliestSpellingOffset(line, bitThatWasSet);
+                const std::size_t setClauseAt = line.find(kSaysWhichIsSet);
+                const std::size_t neededAt = EarliestSpellingOffset(line, bitThatWasNeeded);
+                const std::size_t clearClauseAt = line.find(kSaysWhichIsClear);
+                const bool everyPartIsThere =
+                    refusedAt != std::string::npos && setAt != std::string::npos &&
+                    setClauseAt != std::string::npos && neededAt != std::string::npos &&
+                    clearClauseAt != std::string::npos;
+                // "<set bit> ... is set but ... <needed bit> ... is clear", strictly in that
+                // order. Swapping the caller's two arguments breaks the chain, which is the
+                // whole of F-v2-m1.
+                const bool inTheRightDirection =
+                    everyPartIsThere && setAt < setClauseAt && setClauseAt < neededAt &&
+                    neededAt < clearClauseAt;
+                if (atErrorSeverity && inTheRightDirection) {
+                    return line;
+                }
+                if (newline == std::string::npos) break;
+                pos = newline + 1;
+            }
+            return std::string();
+        }
+
+        // The three accepted spellings of each of the two P4a bits this file's two refusal lanes
+        // are about. MGPipe.h: bit 10 = kMGPipeSubsystemTextureResources = 0x400,
+        // bit 11 = kMGPipeSubsystemSamplers = 0x800.
+        std::vector<std::string> SamplerBitSpellings() {
+            return {"kMGPipeSubsystemSamplers", "(bit 11)", "0x800"};
+        }
+
+        std::vector<std::string> TextureResourceBitSpellings() {
+            return {"kMGPipeSubsystemTextureResources", "(bit 10)", "0x400"};
+        }
+
+        class ObjectSubsystemControlScenario : public ScenarioTest {
+        protected:
+            void SetUp() override {
+                ScenarioTest::SetUp();
+                if (!Ready()) return;
+                m_lane = LaneName();
+                std::string error;
+                m_program = CompileProgram(kVS, kFS, &error);
+                ASSERT_NE(m_program, 0u) << error;
+
+                static const Vertex quad[6] = {{-1.0f, -1.0f}, {1.0f, -1.0f}, {1.0f, 1.0f},
+                                               {-1.0f, -1.0f}, {1.0f, 1.0f},  {-1.0f, 1.0f}};
+                glGenBuffers(1, &m_quadBuffer);
+                glBindBuffer(GL_ARRAY_BUFFER, m_quadBuffer);
+                glBufferData(GL_ARRAY_BUFFER, sizeof(quad), quad, GL_STATIC_DRAW);
+                glGenVertexArrays(1, &m_vao);
+                glBindVertexArray(m_vao);
+                glEnableVertexAttribArray(0);
+                glVertexAttribPointer(0, 2, GL_FLOAT, GL_FALSE, sizeof(Vertex), nullptr);
+                glBindVertexArray(0);
+                RecordProperty("lane", m_lane.empty() ? "ambient" : m_lane.c_str());
+            }
+
+            void TearDown() override {
+                if (!Ready()) return;
+                glUseProgram(0);
+                glBindVertexArray(0);
+                glBindSampler(0, 0);
+                glBindBuffer(GL_ARRAY_BUFFER, 0);
+                if (m_vao != 0) glDeleteVertexArrays(1, &m_vao);
+                if (m_quadBuffer != 0) glDeleteBuffers(1, &m_quadBuffer);
+                if (m_program != 0) glDeleteProgram(m_program);
+            }
+
+            // GTEST_SKIP() returns from the function it is written in, so this cannot report
+            // through a return value; every caller pairs it with `if (IsSkipped()) return;`.
+            void SkipUnlessTheLaneIsAssertableHere(bool needsTheEmitters) {
+                if (m_lane.empty()) {
+                    GTEST_SKIP() << "runs only in its own lane: the three ObjectSubsystemControl. "
+                                    "ctest entries set " << kLaneMarker
+                                 << " together with the MOBILEGL_PIPE_PUSH bitmask that arm means, "
+                                    "MOBILEGL_PIPE_STATS=1, MOBILEGL_PIPE_STATS_PERIOD=1 and a "
+                                    "private MOBILEGL_LOG_FILE_PATH. None of that is configured in "
+                                    "the ambient entries, and the ambient log is shared, so a read "
+                                    "here would race.";
+                    return;
+                }
+                if (!BuildMarkerIsSet("MGITEST_PIPE_PUSH_BUILD")) {
+                    GTEST_SKIP() << "this library was built without MOBILEGL_PIPE_PUSH: there are no "
+                                    "subsystem bits to clear, P4a's five CallClass members do not "
+                                    "exist and the summary line carries no emit[...] bracket. The "
+                                    "entry is registered here anyway so that `ctest -L "
+                                    "integration-gpu` names the same tests in the pull build and the "
+                                    "push build (gate G2).";
+                    return;
+                }
+                if (needsTheEmitters && !BuildMarkerIsSet("MGITEST_PIPE_OBJECT_EMITTER_PRESENT")) {
+                    GTEST_SKIP() << "subsystem not implemented on this tree: no source under "
+                                    "MobileGL/MG_Impl/Pipe/ emits FramebufferEmissions, so nothing "
+                                    "sends a P4a record, every counter in the emit[] bracket is "
+                                    "structurally zero in BOTH lanes and the difference between them "
+                                    "is not observable yet. P4a packages B (framebuffer, texture) "
+                                    "and C (sampler, image, program) own those emitters; this "
+                                    "control arms itself when they land, whatever files they use.";
+                    return;
+                }
+                if (PipeStatsWindow::LibraryLogPath().empty()) {
+                    GTEST_SKIP() << "the lane configured no MOBILEGL_LOG_FILE_PATH, and the library's "
+                                    "own log is the only channel this module has for reading "
+                                    "PipeStats and the bring-up's refusal line";
+                    return;
+                }
+            }
+
+            // The workload, and every one of P4a's four families is in it exactly once per draw:
+            // a USER FRAMEBUFFER with a texture attachment (bit 9), a TEXTURE with parameters and
+            // an upload (bit 10), an explicit SAMPLER OBJECT on the unit (bit 11) and a PROGRAM
+            // with a default-uniform-block write (bit 12). A lane that steered only one of the four
+            // would move only its own counter, which is why they are counted separately.
+            void RunTheWorkload() {
+                std::vector<std::uint8_t> texels(kTextureSize * kTextureSize * 4);
+                for (std::size_t i = 0; i < texels.size(); i += 4) {
+                    texels[i] = 0;
+                    texels[i + 1] = 255;
+                    texels[i + 2] = 0;
+                    texels[i + 3] = 255;
+                }
+                glGenTextures(1, &m_texture);
+                glBindTexture(GL_TEXTURE_2D, m_texture);
+                glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, kTextureSize, kTextureSize, 0, GL_RGBA,
+                             GL_UNSIGNED_BYTE, texels.data());
+                glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+                glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+                glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_BASE_LEVEL, 0);
+                glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAX_LEVEL, 0);
+
+                glGenSamplers(1, &m_sampler);
+                glSamplerParameteri(m_sampler, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+                glSamplerParameteri(m_sampler, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+                glSamplerParameteri(m_sampler, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
+                glSamplerParameteri(m_sampler, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
+
+                // The user framebuffer, drawn into once per iteration so that the framebuffer
+                // record has a reason to move: the binding alternates between it and the default
+                // framebuffer, which is exactly what a per-target set_framebuffer_state counts.
+                glGenTextures(1, &m_attachment);
+                glBindTexture(GL_TEXTURE_2D, m_attachment);
+                glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, kTextureSize, kTextureSize, 0, GL_RGBA,
+                             GL_UNSIGNED_BYTE, nullptr);
+                glBindTexture(GL_TEXTURE_2D, 0);
+                glGenFramebuffers(1, &m_fbo);
+                glBindFramebuffer(GL_FRAMEBUFFER, m_fbo);
+                glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D,
+                                       m_attachment, 0);
+                BindDefaultFramebuffer();
+
+                for (int draw = 0; draw < kDrawsInTheWindow; ++draw) {
+                    // Into the user framebuffer...
+                    glBindFramebuffer(GL_FRAMEBUFFER, m_fbo);
+                    glViewport(0, 0, kTextureSize, kTextureSize);
+                    glUseProgram(m_program);
+                    glUniform1i(glGetUniformLocation(m_program, "uTex"), 0);
+                    glActiveTexture(GL_TEXTURE0);
+                    glBindTexture(GL_TEXTURE_2D, m_texture);
+                    glBindSampler(0, m_sampler);
+                    glBindVertexArray(m_vao);
+                    glDrawArrays(GL_TRIANGLES, 0, 6);
+                    // ...and into the default one, which is what the case reads back.
+                    BindDefaultFramebuffer();
+                    glViewport(0, 0, Gl().Width(), Gl().Height());
+                    glDrawArrays(GL_TRIANGLES, 0, 6);
+                    // One sub-region upload per iteration, so the client-side texture upload
+                    // counter (ctu) has something to count and the server's tex[emit=] has the
+                    // same something.
+                    const std::uint8_t green[4] = {0, 255, 0, 255};
+                    glBindTexture(GL_TEXTURE_2D, m_texture);
+                    glTexSubImage2D(GL_TEXTURE_2D, 0, draw % kTextureSize, 0, 1, 1, GL_RGBA,
+                                    GL_UNSIGNED_BYTE, green);
+                }
+            }
+
+            void ReleaseTheWorkload() {
+                glBindSampler(0, 0);
+                glBindTexture(GL_TEXTURE_2D, 0);
+                BindDefaultFramebuffer();
+                if (m_fbo != 0) glDeleteFramebuffers(1, &m_fbo);
+                if (m_sampler != 0) glDeleteSamplers(1, &m_sampler);
+                if (m_texture != 0) glDeleteTextures(1, &m_texture);
+                if (m_attachment != 0) glDeleteTextures(1, &m_attachment);
+                m_fbo = m_sampler = m_texture = m_attachment = 0;
+            }
+
+            std::string m_lane;
+            GLuint m_program = 0;
+            GLuint m_vao = 0;
+            GLuint m_quadBuffer = 0;
+            GLuint m_texture = 0;
+            GLuint m_attachment = 0;
+            GLuint m_sampler = 0;
+            GLuint m_fbo = 0;
+        };
+
+        // ONE case per lane, and it is a constraint rather than a preference: this case READS the
+        // library log, the log is a per-LANE resource (the library opens it fopen(path, "w"), so
+        // every process in a lane truncates it), and a second case in the same lane would race this
+        // one under `ctest -j` with a failure indistinguishable from "the counter was never
+        // emitted". The CMake registration gives each lane a TEST_FILTER naming one case.
+        TEST_F(ObjectSubsystemControlScenario, ClearingTheP4aBitsStopsTheEmissionsAndNotThePixels) {
+            if (!Ready()) return;
+            SkipUnlessTheLaneIsAssertableHere(/*needsTheEmitters=*/true);
+            if (IsSkipped()) return;
+            if (LaneIsAConsumerLane(m_lane)) {
+                GTEST_SKIP() << "the two consumer lanes run their own case instead "
+                                "(TheAppliersNoConsumerBeltNeverFiresBehindTheClientsGate). They "
+                                "are at the phase default on both backends and their subject is "
+                                "c0f's gate/belt pair, not the on/off A/B: on the backend with no "
+                                "consumer the emit[] bracket is structurally zero AT the default "
+                                "mask, which is neither the on-lane's expectation nor the "
+                                "off-lane's.";
+            }
+            if (LaneIsARefusalLane(m_lane)) {
+                GTEST_SKIP() << "the refusal lanes run their own case instead (0x9ff -> "
+                                "ASamplerBitWithoutTheTextureBitIsRefusedAndNamed, 0x5ff -> "
+                                "ATextureBitWithoutTheSamplerBitIsRefusedAndNamed): a refused "
+                                "subsystem's emission counts are neither the on-lane's nor the "
+                                "off-lane's, and asserting either would be reading a third arm as "
+                                "if it were one of the two.";
+            }
+
+            BindDefaultFramebuffer();
+            Gl().EndFrame(); // close the setup window: everything below is one window
+
+            ClearTo(0.0f, 0.0f, 0.0f, 1.0f);
+            RunTheWorkload();
+            ASSERT_EQ(FirstGLError(), GLenum(GL_NO_ERROR)) << "the workload left a GL error behind";
+            const Image image = ReadPixels(Gl().Width(), Gl().Height());
+            Gl().EndFrame(); // the swap that emits the window covering exactly the work above
+
+            const PipeStatsWindow::Window window = PipeStatsWindow::LastFromLaneLog();
+            ASSERT_TRUE(window.found)
+                << "no 'MGPipe stats:' line in " << PipeStatsWindow::LibraryLogPath()
+                << ". This IS a push build (the lane checked MGITEST_PIPE_PUSH_BUILD before getting "
+                   "here), so either MOBILEGL_PIPE_STATS / MOBILEGL_PIPE_STATS_PERIOD did not reach "
+                   "the process, or no summary line was emitted at all because nothing reached "
+                   "PipeStats::OnPresent.";
+            RecordProperty("stats_line", window.line.c_str());
+
+            // The five counters of the emit[] bracket, read individually so that a lane which
+            // steered one family and not another says WHICH.
+            const long long framebuffer = PipeStatsWindow::CounterOrAbsent(window, "fbe");
+            const long long samplerViews = PipeStatsWindow::CounterOrAbsent(window, "sve");
+            const long long samplerStates = PipeStatsWindow::CounterOrAbsent(window, "sse");
+            const long long shaderImages = PipeStatsWindow::CounterOrAbsent(window, "sie");
+            const long long clientUploads = PipeStatsWindow::CounterOrAbsent(window, "ctu");
+            ASSERT_GE(framebuffer, 0)
+                << "the summary line carries no fbe= field, so this build's PipeStats has no P4a "
+                   "emission counters to read: "
+                << window.line;
+            ASSERT_GE(samplerViews, 0) << "no sve= field: " << window.line;
+            ASSERT_GE(samplerStates, 0) << "no sse= field: " << window.line;
+            ASSERT_GE(shaderImages, 0) << "no sie= field: " << window.line;
+            ASSERT_GE(clientUploads, 0) << "no ctu= field: " << window.line;
+            const long long total = framebuffer + samplerViews + samplerStates + shaderImages +
+                                    clientUploads;
+
+            if (m_lane == kLaneOn) {
+                EXPECT_GT(total, 0)
+                    << "with bits 9|10|11|12 SET the four P4a families are the path this workload "
+                       "takes - a user framebuffer bound and unbound "
+                    << kDrawsInTheWindow
+                    << " times, a texture with parameters and a sub-region upload per iteration, an "
+                       "explicit sampler object on the unit and a program with a default-uniform "
+                       "write - so the window's emit[] bracket must carry something. All five "
+                       "reading zero means the emitters never ran on the arm that is supposed to run "
+                       "them. It reported: "
+                    << window.line;
+                // The framebuffer family on its own, because it is the one that would be hidden by
+                // a large upload count: a suppressor that stopped suppressing shows up as fbe
+                // tracking the DRAW count, and a family that never emitted shows up as zero.
+                EXPECT_GT(framebuffer, 0)
+                    << "fbe= is zero on the ON lane: set_framebuffer_state never went out even "
+                       "though the workload bound a user framebuffer and the default framebuffer "
+                    << kDrawsInTheWindow << " times each. " << window.line;
+            } else if (m_lane == kLaneOff) {
+                EXPECT_EQ(total, 0)
+                    << "with bits 9|10|11|12 CLEARED (MOBILEGL_PIPE_PUSH=0x1ff, P3a's default) the "
+                       "frontend dispatch must fall through to the legacy MGB_CTX-reading arms and "
+                       "emit nothing through any of the four P4a families, so every counter in the "
+                       "emit[] bracket must be zero. A non-zero count here is the dead-switch "
+                       "reading: the bits are being ignored, both arms run the same code, and every "
+                       "push-vs-pull number taken against this A/B is measuring one arm twice. It "
+                       "reported: "
+                    << window.line;
+            } else {
+                FAIL() << "unknown " << kLaneMarker << " value '" << m_lane
+                       << "': the arms are on / off / refused / refused-texture / consumer / "
+                          "no-consumer. Reading an unrecognised name as any of them would make "
+                          "this lane assert another arm's expectation while claiming to test "
+                          "this one.";
+            }
+
+            // ... and the picture is the same whichever arm ran.
+            EXPECT_TRUE(RegionIsMostly(image, kInset, image.Width() - kInset, kInset,
+                                       image.Height() - kInset, "green", 0.0,
+                                       "the sampled draw [" + m_lane + "]"))
+                << "the subsystem bits changed what is DRAWN, which is not an A/B - the handle path "
+                   "and the legacy path must produce the same pixels from the same texture, sampler "
+                   "and framebuffer.";
+
+            ReleaseTheWorkload();
+        }
+
+        // ------------------------------------------------------------------------------------
+        // D-K2's dependency refusal, in the direction that has to be refused.
+        //
+        // 0x9ff is bits 0..8 (everything P3a shipped) plus bit 11 (samplers) and WITHOUT bit 10
+        // (texture resources). Every MGPBoundView::Texture and every MGPImageView::Res names a
+        // Texture handle, and only bit 10 populates the texture slot table, so with bit 11 alone
+        // every lookup would miss and the unit walk would `continue` without unbinding - a
+        // half-run subsystem, which ROADMAP.md:7 forbids as loudly as a dead switch. The bring-up
+        // logs ONE error naming both bits, refuses bit 11, and runs the legacy sampler arm.
+        //
+        // TWO ASSERTIONS, and the second is the one that stops this from being a log-scraping test:
+        // the refusal is NAMED in the library's own log, and the run then draws the same picture as
+        // every other lane. A refusal that aborted the process, and a refusal that silently let the
+        // half-configured arm run, are both failures - and they look completely different here.
+        // ------------------------------------------------------------------------------------
+        TEST_F(ObjectSubsystemControlScenario, ASamplerBitWithoutTheTextureBitIsRefusedAndNamed) {
+            if (!Ready()) return;
+            // needsTheEmitters=false: the refusal is a BRING-UP decision made from the bitmask
+            // alone, so it is assertable before any emitter exists - which is exactly what makes it
+            // the one P4a control that is not vacuous on the contract tree.
+            SkipUnlessTheLaneIsAssertableHere(/*needsTheEmitters=*/false);
+            if (IsSkipped()) return;
+            if (m_lane != kLaneRefused) {
+                GTEST_SKIP() << "runs only in the refusal lane (MOBILEGL_PIPE_PUSH=0x9ff): the "
+                                "on/off lanes configure a mask whose dependencies are all satisfied, "
+                                "so there is no refusal there to find and a search for one would "
+                                "report a healthy lane as red.";
+            }
+            // The refusal is decided from the bitmask, but it is a BACKEND's decision: D-K2 puts it
+            // in ResolveSamplersSubsystemArm(), beside the bit-8-requires-bit-7 refusal that
+            // already ships, and that function is package D's (Managers.cpp). A backend that does
+            // not yet honour P4a's mask at all cannot refuse a dependency inside it, so on such a
+            // tree there is nothing here to find and this case SKIPS rather than reporting the
+            // absence of an unimplemented subsystem as a failure. The marker is the same one
+            // HandleRecycle's P4a cases read - "does any source under this backend name one of the
+            // four P4a subsystem constants" - because naming the constant is exactly what honouring
+            // the mask means.
+            {
+                const std::string& backend = Gl().BackendName();
+                const std::string marker =
+                    "MGITEST_HANDLE_REKEY_OBJECTS_" + (backend == "DirectVulkan"
+                                                           ? std::string("DirectVulkan")
+                                                           : std::string("DirectGLES"));
+                if (!BuildMarkerIsSet(marker.c_str())) {
+                    GTEST_SKIP() << "subsystem not implemented on this tree: no source under "
+                                    "MobileGL/MG_Backend/"
+                                 << backend
+                                 << " names any of kMGPipeSubsystem{Framebuffer, TextureResources, "
+                                    "Samplers, Programs}, so this backend does not honour P4a's mask "
+                                    "and cannot refuse a dependency inside it. D-K2's refusal lives "
+                                    "in ResolveSamplersSubsystemArm() beside the bit-8-requires-bit-7 "
+                                    "one that already ships (Managers.cpp:2393-2410), which is P4a "
+                                    "package D's file; this control arms itself when that lands. The "
+                                    "lane itself is not wasted: the library came up under 0x9ff, "
+                                    "which on a tree with no P4a arm is P3a's mask plus one inert "
+                                    "bit, and a mask that aborted a bring-up would have failed this "
+                                    "entry before the skip.";
+                }
+            }
+
+            BindDefaultFramebuffer();
+            ClearTo(0.0f, 0.0f, 0.0f, 1.0f);
+            RunTheWorkload();
+            ASSERT_EQ(FirstGLError(), GLenum(GL_NO_ERROR))
+                << "the workload left a GL error behind on the refused lane, which would mean the "
+                   "refusal did not fall back cleanly to the legacy arm";
+            const Image image = ReadPixels(Gl().Width(), Gl().Height());
+            Gl().EndFrame();
+
+            const std::string log = PipeStatsWindow::ReadWholeFile(PipeStatsWindow::LibraryLogPath());
+            ASSERT_FALSE(log.empty())
+                << "the library wrote nothing to " << PipeStatsWindow::LibraryLogPath()
+                << ", so the refusal cannot be read back. MOBILEGL_LOG_FILE_PATH is the only channel "
+                   "this module has for the library's own report.";
+            // ONE LINE, at ERROR severity, saying it refused and naming BOTH bits. See
+            // FindTheRefusalLine: a substring search over the whole file cannot go red for the
+            // reason this case claims (F-M6).
+            const std::string refusal =
+                FindTheRefusalLine(log, SamplerBitSpellings(), TextureResourceBitSpellings());
+            EXPECT_FALSE(refusal.empty())
+                << "MOBILEGL_PIPE_PUSH=0x9ff sets the sampler subsystem (bit 11) without the texture "
+                   "resource subsystem (bit 10) it depends on, and no single ERROR line of the "
+                   "library's log both says it REFUSED and names the two bits. D-K2 requires ONE "
+                   "MGLOG_E naming both and a fall back to the legacy sampler arm; a mask that is "
+                   "silently half-honoured is the failure this case exists to catch, and it is "
+                   "invisible in the pixels by construction. Accepted spellings per bit are the "
+                   "constant's name, '(bit 11)' / '(bit 10)', and '0x800' / '0x400'. The log was "
+                << log.size() << " bytes and is at " << PipeStatsWindow::LibraryLogPath() << ".";
+            if (!refusal.empty()) {
+                // Printed on the pass as well: a reader of a green refusal lane must be able to
+                // see the sentence the lane went green on.
+                std::cout << "[ ObjectSubsystemControl ] refusal line: " << refusal << std::endl;
+                RecordProperty("refusal_line", refusal.c_str());
+            }
+
+            EXPECT_TRUE(RegionIsMostly(image, kInset, image.Width() - kInset, kInset,
+                                       image.Height() - kInset, "green", 0.0,
+                                       "the sampled draw [refused]"))
+                << "the refused configuration did not draw what every other lane draws. A refusal is "
+                   "supposed to run the LEGACY arm, which is the arm that ships in a pull build - so "
+                   "the pixels are the one thing it may not change.";
+
+            ReleaseTheWorkload();
+        }
+
+        // ------------------------------------------------------------------------------------
+        // D-K2's FOURTH dependency row, in the OTHER direction: bit 10 without bit 11 (ID-15).
+        //
+        // 0x5ff is bits 0..8 plus bit 10 (texture resources) and WITHOUT bit 11 (samplers).
+        //
+        // WHY THIS IS A REFUSAL AND NOT THE "FINE" MIRROR PAIR THE BRIEF ORIGINALLY CALLED IT.
+        // BRIEF-P4A.md's D-K2 says "bit 10 without bit 11 is fine", and that sentence is wrong for
+        // P4a AS BUILT: MGPTextureParams carries a BuiltinSampler, which is a SamplerCso HANDLE,
+        // and only bit 11 mints sampler CSOs - c0b's four unconditional mints deliberately exclude
+        // that kind (contract-v2.md), and package C content-addresses them through its own cache
+        // (ID-14). With bit 10 set and bit 11 clear every set_texture_params would therefore carry
+        // a NULL BuiltinSampler, which the applier treats as Fatal{ProtocolCorruption} (wire H1),
+        // and minting it client-side in the arm that exists to exclude samplers was rejected. So
+        // the dependency is real and it has to be refused at bring-up, exactly like bit 11 without
+        // bit 10 above and bit 8 without bit 7 one phase earlier. ID-15 puts the refusal in the
+        // texture family's Resolve*SubsystemArm - package D's Managers.cpp - and this case is the
+        // pin that says it is there.
+        //
+        // ON A TREE WHOSE BACKEND DOES NOT HONOUR P4a's MASK THIS SKIPS, NAMED, exactly as the
+        // 0x9ff case does and for the same reason: a backend that never reads the four constants
+        // cannot refuse a dependency between two of them, and reporting the absence of an
+        // unimplemented subsystem as a failure is what ID-2 forbids. Once the backend DOES name
+        // them the case is a hard pin, which is the point - if D's texture-family resolver honours
+        // the mask and does not carry this row, this entry is where that shows.
+        //
+        // WHAT THIS ARM DOES ON THE INTEGRATED TREE, corrected (review F-v2-m2). An earlier
+        // round's report told the integrator to expect this lane to go RED between esprytobj's
+        // integration and package D's rework, and to read that red as expected. That window does
+        // not exist: esprytobj v2 already carries D-K2's fourth row - Managers.cpp's
+        // ResolveTextureResourceSubsystemArm refuses bit 10 without bit 11 with the sentence this
+        // case matches - so the arm ARMS AND PASSES. A red here is therefore a real finding about
+        // that resolver (it stopped refusing, refused for the wrong reason, or printed the mirror
+        // sentence, which the direction check above is what catches) and must not be waved
+        // through as a sequencing artefact.
+        // ------------------------------------------------------------------------------------
+        TEST_F(ObjectSubsystemControlScenario, ATextureBitWithoutTheSamplerBitIsRefusedAndNamed) {
+            if (!Ready()) return;
+            // needsTheEmitters=false, for the 0x9ff case's reason: a bring-up decision made from
+            // the bitmask alone is assertable before any emitter exists.
+            SkipUnlessTheLaneIsAssertableHere(/*needsTheEmitters=*/false);
+            if (IsSkipped()) return;
+            if (m_lane != kLaneRefusedTexture) {
+                GTEST_SKIP() << "runs only in the texture-side refusal lane "
+                                "(MOBILEGL_PIPE_PUSH=0x5ff): every other lane configures a mask "
+                                "whose dependencies are satisfied or a different refusal, so there "
+                                "is nothing here to find and a search for one would report a "
+                                "healthy lane as red.";
+            }
+            {
+                const std::string& backend = Gl().BackendName();
+                const std::string marker =
+                    "MGITEST_HANDLE_REKEY_OBJECTS_" + (backend == "DirectVulkan"
+                                                           ? std::string("DirectVulkan")
+                                                           : std::string("DirectGLES"));
+                if (!BuildMarkerIsSet(marker.c_str())) {
+                    GTEST_SKIP() << "subsystem not implemented on this tree: no source under "
+                                    "MobileGL/MG_Backend/"
+                                 << backend
+                                 << " names any of kMGPipeSubsystem{Framebuffer, TextureResources, "
+                                    "Samplers, Programs}, so this backend does not honour P4a's mask "
+                                    "and cannot refuse a dependency inside it. D-K2's fourth row "
+                                    "(bit 10 requires bit 11, ID-15) lives in the texture family's "
+                                    "Resolve*SubsystemArm beside the bit-11-requires-bit-10 and "
+                                    "bit-8-requires-bit-7 refusals, which is P4a package D's file; "
+                                    "this control arms itself when that lands. The lane itself is "
+                                    "not wasted: the library came up under 0x5ff, which on a tree "
+                                    "with no P4a arm is P3a's mask plus one inert bit, and a mask "
+                                    "that aborted a bring-up would have failed this entry before "
+                                    "the skip.";
+                }
+            }
+
+            BindDefaultFramebuffer();
+            ClearTo(0.0f, 0.0f, 0.0f, 1.0f);
+            RunTheWorkload();
+            ASSERT_EQ(FirstGLError(), GLenum(GL_NO_ERROR))
+                << "the workload left a GL error behind on the refused lane, which would mean the "
+                   "refusal did not fall back cleanly to the legacy arm";
+            const Image image = ReadPixels(Gl().Width(), Gl().Height());
+            Gl().EndFrame();
+
+            const std::string log = PipeStatsWindow::ReadWholeFile(PipeStatsWindow::LibraryLogPath());
+            ASSERT_FALSE(log.empty())
+                << "the library wrote nothing to " << PipeStatsWindow::LibraryLogPath()
+                << ", so the refusal cannot be read back. MOBILEGL_LOG_FILE_PATH is the only channel "
+                   "this module has for the library's own report.";
+            // The same line shape as the 0x9ff arm, with the two bits' roles swapped: the bit that
+            // was SET is the texture-resource one and the bit it NEEDED is the sampler one. The
+            // swap is now a REAL difference between the two cases: FindTheRefusalLine requires the
+            // set bit to be named before " is set but " and the needed bit after it (F-v2-m1), so
+            // this call and the 0x9ff one above accept disjoint sentences. Espryt's is
+            // "kMGPipeSubsystemTextureResources (bit 10) is set but kMGPipeSubsystemSamplers
+            // (bit 11) is clear; MGPTextureParams::BuiltinSampler is a SamplerCso handle, only
+            // bit 11 mints sampler CSOs, and the applier's verdict for a null one is
+            // Fatal{ProtocolCorruption} - REFUSING the dependent bit and running the legacy arm.
+            // Set both bits, or clear both" (Managers.cpp, ResolveTextureResourceSubsystemArm).
+            const std::string refusal =
+                FindTheRefusalLine(log, TextureResourceBitSpellings(), SamplerBitSpellings());
+            EXPECT_FALSE(refusal.empty())
+                << "MOBILEGL_PIPE_PUSH=0x5ff sets the texture resource subsystem (bit 10) without "
+                   "the sampler subsystem (bit 11) that MGPTextureParams::BuiltinSampler depends on, "
+                   "and no single ERROR line of the library's log both says it REFUSED and names the "
+                   "two bits. Only bit 11 mints sampler CSOs, so every set_texture_params emitted "
+                   "under this mask would carry a null BuiltinSampler and the applier's Fatal is the "
+                   "next thing that happens - which is why this pair is a refusal at bring-up and "
+                   "not the harmless mirror of the 0x9ff one. Accepted spellings per bit are the "
+                   "constant's name, '(bit 10)' / '(bit 11)', and '0x400' / '0x800'. The log was "
+                << log.size() << " bytes and is at " << PipeStatsWindow::LibraryLogPath() << ".";
+            if (!refusal.empty()) {
+                std::cout << "[ ObjectSubsystemControl ] refusal line: " << refusal << std::endl;
+                RecordProperty("refusal_line", refusal.c_str());
+            }
+
+            EXPECT_TRUE(RegionIsMostly(image, kInset, image.Width() - kInset, kInset,
+                                       image.Height() - kInset, "green", 0.0,
+                                       "the sampled draw [refused-texture]"))
+                << "the refused configuration did not draw what every other lane draws. A refusal is "
+                   "supposed to run the LEGACY arm, which is the arm that ships in a pull build - so "
+                   "the pixels are the one thing it may not change.";
+
+            ReleaseTheWorkload();
+        }
+
+        // ------------------------------------------------------------------------------------
+        // c0f's GATE AND BELT, MEASURED TOGETHER (ID-39, ID-40).
+        //
+        // WHAT WENT WRONG AND WHY IT NEEDS A LANE. P4a's four families were wired without the
+        // gate P3a's buffers have had since PipeFill.cpp ~656: emission required the family's bit
+        // and nothing else. On Magma, which registers no MGPipeResourceOps, the client therefore
+        // emitted, THE APPLIER ACCEPTED, the client cleared its dirty flags on that acceptance -
+        // and Magma's legacy path then found nothing to upload. Sixty-six DirectVulkan cases went
+        // red at once, all texture-upload-shaped, and every one of them was green at 0x1ff. The
+        // fix has two halves that are deliberately independent: the client's gate (bit N AND
+        // wired AND a backend registered the ops) and the applier's belt (every P4a entry point
+        // returns accepted = false and counts RefusedNoConsumer when none did).
+        //
+        // THE ASSERTION IS THAT THE BELT NEVER FIRES, and it is the same assertion on both
+        // backends, which is what makes it worth having twice:
+        //
+        //   no-consumer (DirectVulkan, 0x1fff): the belt is the SAFETY NET. A non-zero count here
+        //     means a record reached the applier on a backend with no consumer - i.e. the client
+        //     gate leaked and only the belt stopped the dirty flag from being cleared. That is
+        //     ID-39's bug caught one layer later, and it is invisible in these pixels because the
+        //     belt does its job; the 66 red cases were in another suite entirely.
+        //   consumer (DirectGLES, 0x1fff): the CONTROL. Espryt registers the ops, so no entry
+        //     point may take the no-consumer arm at all. Without this lane a green above could
+        //     also mean "nothing is ever emitted anywhere", which is exactly what a gate that was
+        //     accidentally always-false would look like.
+        //
+        // A DELTA, not an absolute: the counter is process-global and other cases in this binary
+        // run before this one. MGPipeApplierReset also zeroes it, so a count that went DOWN is
+        // read as "the applier was reset and everything since is `after`" rather than as an
+        // underflow.
+        // ------------------------------------------------------------------------------------
+        TEST_F(ObjectSubsystemControlScenario, TheAppliersNoConsumerBeltNeverFiresBehindTheClientsGate) {
+            if (!Ready()) return;
+            // needsTheEmitters=false: the assertion is that a counter did NOT move, which is
+            // meaningful before the emitters land as well as after - and on the no-consumer lane
+            // it is meaningful precisely BECAUSE nothing may be emitted there.
+            SkipUnlessTheLaneIsAssertableHere(/*needsTheEmitters=*/false);
+            if (IsSkipped()) return;
+            if (!LaneIsAConsumerLane(m_lane)) {
+                GTEST_SKIP() << "runs only in the two consumer lanes (MGITEST_OBJECT_SUBSYSTEM_LANE="
+                             << kLaneConsumer << " / " << kLaneNoConsumer
+                             << "), which pin MOBILEGL_PIPE_PUSH at the phase default on the two "
+                                "backends. Every other lane configures a mask or a backend whose "
+                                "emission shape is a different question.";
+            }
+
+            unsigned long long before = 0;
+            if (!PeekPipeApplierRefusedNoConsumer(&before)) {
+                GTEST_SKIP() << "MGPipeApplierState::RefusedNoConsumer is out of reach here: there "
+                                "is no applier in a PULL build (it is #if MOBILEGL_PIPE_PUSH), and "
+                                "on Android this module links the shipping libMobileGL.so built "
+                                "-fvisibility=hidden. 'Could not look' is not 'did not fire'.";
+            }
+
+            BindDefaultFramebuffer();
+            ClearTo(0.0f, 0.0f, 0.0f, 1.0f);
+            RunTheWorkload();
+            ASSERT_EQ(FirstGLError(), GLenum(GL_NO_ERROR))
+                << "the workload left a GL error behind on the " << m_lane << " lane";
+            const Image image = ReadPixels(Gl().Width(), Gl().Height());
+            Gl().EndFrame();
+
+            unsigned long long after = 0;
+            ASSERT_TRUE(PeekPipeApplierRefusedNoConsumer(&after))
+                << "the counter could be read before the workload and not after it";
+            // Down means MGPipeApplierReset ran inside the window, so everything still counted is
+            // what happened since - which is the number this case is about either way.
+            const unsigned long long fired = after >= before ? after - before : after;
+
+            std::cout << "[ ObjectSubsystemControl ] " << m_lane
+                      << " lane: applier RefusedNoConsumer " << before << " -> " << after
+                      << " over the workload (delta " << fired << ")" << std::endl;
+            RecordProperty("refused_no_consumer_delta", static_cast<int>(fired));
+
+            EXPECT_EQ(fired, 0u)
+                << "the applier's no-consumer BELT fired " << fired
+                << " time(s) during this workload on the " << m_lane
+                << " lane. The belt exists so that a P4a record arriving on a backend that "
+                   "registered no MGPipeResourceOps is refused rather than accepted - and an "
+                   "accepted record is what makes the client clear the dirty flags whose texels "
+                   "nobody then uploads (ID-39: sixty-six DirectVulkan cases, all texture-upload "
+                   "shaped). A non-zero count means the CLIENT'S GATE let an emission through and "
+                   "only the belt caught it: the two are supposed to agree, and PipeFill's "
+                   "P4aFamilyHasItsConsumer() is where they stopped.";
+
+            // The pixels, on both lanes, for the reason every arm of this file asserts them: a
+            // backend running its legacy path because no consumer is registered must draw exactly
+            // what a backend running the handle arm draws.
+            EXPECT_TRUE(RegionIsMostly(image, kInset, image.Width() - kInset, kInset,
+                                       image.Height() - kInset, "green", 0.0,
+                                       "the sampled draw [" + m_lane + "]"))
+                << "the " << m_lane
+                << " lane did not draw what every other lane draws, so whatever the counter says, "
+                   "this configuration is not running the workload correctly.";
+
+            ReleaseTheWorkload();
+        }
+
+    } // namespace
+} // namespace MGITest

MobileGL/MG_IntegrationTest/Scenarios/P4aSeamAuditScenario.cpp

@@ -0,0 +1,803 @@
+// MobileGL - MobileGL/MG_IntegrationTest/Scenarios/P4aSeamAuditScenario.cpp
+// Copyright (c) 2026 MobileGL-Dev
+// Licensed under the GNU Lesser General Public License v3.0:
+//   https://www.gnu.org/licenses/gpl-3.0.txt
+//   https://www.gnu.org/licenses/lgpl-3.0.txt
+// SPDX-License-Identifier: LGPL-3.0-only
+// End of Source File Header
+//
+// Scenario - THE FOUR SEAMS THE P4a FABLE SEAM AUDIT PROVED, each pinned by the public-GL sequence
+// (or the white-box reading) that was red on the tree the audit read and is green with its fix.
+//
+// The audit's rule, which every case here is an instance of: EVERY FIELD OF EVERY EMITTED RECORD
+// NAMES THE FRONTEND SETTER THAT CHANGES IT, AND THAT SETTER MOVES A COUNTER THE EMITTING BIT'S
+// SHUTTER READS. A record whose field has a setter no shutter sees is a stale record with nothing
+// to refuse - no census line, no Fatal, a wrong picture or a permanent silent fallback - which is
+// why none of the 80 scenarios before this file caught any of the four (Tracker.h carries the
+// record-field -> setter -> shutter table this file is the gate for).
+//
+//   F-3  set_framebuffer_state INLINES an attachment's format (D-C1) and a storage redefinition of
+//        an ATTACHED texture or renderbuffer moved nothing bit 11 read: Espryt's handle arm then
+//        answered its alpha-widening / snorm-clamp / integer masks from the stale copy. AND THE
+//        PRE-HANDLE ARM WAS NOT FRESH EITHER, which these cases found on the 0x1ff / 0 / pull
+//        lanes: a redefinition that keeps the driver id (mutable texture storage regenerated in
+//        place, a renderbuffer re-storaged in place) moves neither the framebuffer's frontend
+//        versions nor the backend-id generation the FBO memo reads, so SyncToBackend never
+//        re-ran and the masks stayed on both arms. The texture half is fixed on both arms OF A
+//        PUSH BUILD (an in-place regeneration now takes the same generation a re-mint takes -
+//        compiled under MOBILEGL_PIPE_PUSH because G1 keeps the pull library byte-identical to
+//        the P4a baseline, so the pull build keeps the pre-P4a hole until the fix lands on dev on
+//        its own and the texture cases decline by name there); the renderbuffer half only on the
+//        handle arm, where the resource record carries the re-storage - on the pre-handle arm a
+//        renderbuffer's twin is only ever reached from inside the FBO walk the memo skips (D-D2's
+//        documented hole, pre-P4a code), so that case asserts on the handle arm and declines by
+//        name elsewhere. Three cases, both directions, texture and renderbuffer. DirectGLES only:
+//        the masks are Espryt's substitution machinery.
+//   F-1  set_sampler_views is resolved for the PROGRAM IN USE and bit 12's shutter read no program
+//        input, so a glUseProgram alone never re-emitted it; E's record epoch (the two set serials)
+//        then kept the program-independent texture sync list from ever rebuilding, and a texture
+//        bound to an EMPTY slot under one program was never synced for the next. One case, both
+//        backends, red as a black quad.
+//   F-2  bit 14's plain-program arm mixed a per-program COUNTER two programs routinely share, so a
+//        program switch never re-emitted set_shader_images and the window stayed the previous
+//        program's - and E's SD-4 (a buffer image never reaching the record at all) is the same
+//        bit through the null -> program transition. One case, white-box, both backends run it.
+//   F-4  BindCurrentUnitSamplers' record arm looked a CONTENT-addressed CSO handle up in the
+//        IDENTITY-keyed twin registry: a miss on every draw, hidden because the pre-handle program
+//        pass bound the same values. One case, white-box: the unit's driver sampler must be the
+//        CSO's own twin.
+//
+// A WHITE-BOX READING THAT CANNOT BE TAKEN IS DECLINED BY NAME AND THE CASE CONTINUES with its
+// public-GL half (the shape TextureParamsWithoutASamplerViewScenario.cpp argues for): a pull
+// build, Magma, or a lane whose mask leaves Espryt's sampler family on its legacy arm has no
+// record arm to assert about, and skipping the whole case there would delete the public-GL
+// verdict those lanes carry. Every decline is printed and RecordProperty'd.
+
+#include <cstdint>
+#include <cstring>
+#include <iostream>
+#include <string>
+#include <vector>
+
+#include "../Harness/HeadlessGL.h"
+#include "../Harness/P4aSeamPeek.h"
+#include "../Harness/ScenarioFixture.h"
+
+#ifdef GLAPI
+#undef GLAPI
+#endif
+#define GL_GLEXT_PROTOTYPES
+#include <GL/gl.h>
+#include <GL/glcorearb.h>
+#undef GL_GLEXT_PROTOTYPES
+
+namespace MGITest {
+    namespace {
+
+        constexpr int kSize = 16;
+        constexpr int kInset = 2;
+
+        // No attributes: the quad's corners come from gl_VertexID, so a bare VAO is all a draw
+        // needs and no vertex-input state can enter any of the sequences below.
+        constexpr const char* kQuadVS = R"(#version 330 core
+void main() {
+    vec2 corner = vec2((gl_VertexID & 1) == 0 ? -1.0 : 1.0,
+                       (gl_VertexID & 2) == 0 ? -1.0 : 1.0);
+    gl_Position = vec4(corner, 0.0, 1.0);
+}
+)";
+
+        constexpr const char* kColorFS = R"(#version 330 core
+uniform vec4 uColor;
+out vec4 oColor;
+void main() { oColor = uColor; }
+)";
+
+        // texelFetch, so WHICH image the unit holds is the whole answer and no filter, wrap or
+        // completeness rule can explain a colour away.
+        constexpr const char* kFetchFS = R"(#version 330 core
+uniform sampler2D uTex;
+out vec4 oColor;
+void main() { oColor = texelFetch(uTex, ivec2(0, 0), 0); }
+)";
+
+        // texture() at (1.5, 1.5): outside the image on both axes, so the WRAP mode of whichever
+        // sampler applies - the unit's sampler object or the texture's built-in one - decides
+        // whether the texel or the border colour comes back.
+        constexpr const char* kOutsideSampleFS = R"(#version 330 core
+uniform sampler2D uTex;
+out vec4 oColor;
+void main() { oColor = texture(uTex, vec2(1.5, 1.5)); }
+)";
+
+        // F-2 / SD-4: two compute programs over BUFFER images (the SD-4 shape - the kind E's I2
+        // flip found never reached the record at all), the second naming one unit more than the
+        // first, and both image-unit counters equal (layout(binding) assigns the unit at link, so
+        // neither program ever moves it through glUniform1i).
+        constexpr const char* kOneBufferImageCS = R"(#version 430 core
+layout(local_size_x = 1) in;
+layout(binding = 0, r32ui) writeonly uniform uimageBuffer i0;
+void main() { imageStore(i0, 0, uvec4(7u, 0u, 0u, 0u)); }
+)";
+
+        constexpr const char* kTwoBufferImagesCS = R"(#version 430 core
+layout(local_size_x = 1) in;
+layout(binding = 0, r32ui) readonly uniform uimageBuffer i0;
+layout(binding = 1, r32ui) writeonly uniform uimageBuffer i1;
+void main() { imageStore(i1, 0, imageLoad(i0, 0) + uvec4(2u, 0u, 0u, 0u)); }
+)";
+
+        class P4aSeamAuditScenario : public ScenarioTest {
+        protected:
+            void SetUp() override {
+                ScenarioTest::SetUp();
+                if (!Ready()) return;
+                glGenVertexArrays(1, &m_vao);
+                glBindVertexArray(m_vao);
+                glDisable(GL_BLEND);
+                glDisable(GL_SCISSOR_TEST);
+                glDisable(GL_DEPTH_TEST);
+                glColorMask(GL_TRUE, GL_TRUE, GL_TRUE, GL_TRUE);
+                while (glGetError() != GL_NO_ERROR) {
+                }
+            }
+
+            void TearDown() override {
+                if (!Ready()) return;
+                glUseProgram(0);
+                glBindVertexArray(0);
+                if (m_vao != 0) glDeleteVertexArrays(1, &m_vao);
+                glBindFramebuffer(GL_FRAMEBUFFER, 0);
+                while (glGetError() != GL_NO_ERROR) {
+                }
+            }
+
+            // The F-3 cases are about Espryt's four cross-object masks, which are its own
+            // substitution machinery (three-channel widening, SNORM/UNORM clamp, integer outputs);
+            // Magma answers the same GL questions on its own terms, so a verdict there would pin
+            // a coincidence - the same reason SnormAttachment and ThreeChannelAttachment skip.
+            // Marks the case skipped; the caller tests IsSkipped() and returns (GTEST_SKIP is a
+            // void statement, so it cannot return the verdict itself).
+            void SkipUnlessEspryt(const char* what) {
+                if (Gl().BackendName() == "DirectGLES") return;
+                GTEST_SKIP() << what << " is a DirectGLES handle-arm seam; backend is " << Gl().BackendName();
+            }
+
+            static void DrawQuad() { glDrawArrays(GL_TRIANGLE_STRIP, 0, 4); }
+
+            // One pixel's RGBA as floats, from the currently bound READ framebuffer.
+            static void ReadPixelFloat(int x, int y, float out[4]) {
+                out[0] = out[1] = out[2] = out[3] = -1.0f;
+                glReadPixels(x, y, 1, 1, GL_RGBA, GL_FLOAT, out);
+            }
+
+            // The white-box gate shared by F-2 and F-4: true when Espryt's sampler family is on
+            // its handle arm in this process, so the applier's unit sets are consumed and an
+            // assertion about them can only be red for its own reason. Prints the decline.
+            bool SamplerHandleArmIsLive(const char* what) {
+                bool live = false;
+                std::string why;
+                if (!PeekEsprytSamplerHandleArmIsLive(&live)) {
+                    why = "the reading cannot be taken here (a pull build, Android, or a backend that "
+                          "is not DirectGLES)";
+                } else if (!live) {
+                    why = "Espryt's sampler family runs its legacy arm in this process "
+                          "(MOBILEGL_PIPE_PUSH leaves bit 11 clear or refuses it)";
+                }
+                if (why.empty()) return true;
+                std::cout << "[ P4aSeamAudit ] white-box reading DECLINED for " << what << ": " << why
+                          << "; the public-GL half of the case still runs" << std::endl;
+                RecordProperty("p4a_seam_white_box", "declined");
+                RecordProperty("p4a_seam_white_box_reason", why);
+                return false;
+            }
+
+            // A 2x2 RGBA8 texture filled with one colour, NEAREST, single level - complete under
+            // every rule, so nothing about completeness can enter the F-1 and F-4 sequences.
+            static GLuint MakeSolidTexture2D(std::uint8_t r, std::uint8_t g, std::uint8_t b) {
+                std::uint8_t texels[2 * 2 * 4];
+                for (int i = 0; i < 4; ++i) {
+                    texels[i * 4 + 0] = r;
+                    texels[i * 4 + 1] = g;
+                    texels[i * 4 + 2] = b;
+                    texels[i * 4 + 3] = 255;
+                }
+                GLuint texture = 0;
+                glGenTextures(1, &texture);
+                glBindTexture(GL_TEXTURE_2D, texture);
+                glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, 2, 2, 0, GL_RGBA, GL_UNSIGNED_BYTE, texels);
+                glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+                glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+                return texture;
+            }
+
+            bool ComputeImagesAreUsable() const {
+                GLint maxImageUnits = 0;
+                glGetIntegerv(GL_MAX_IMAGE_UNITS, &maxImageUnits);
+                GLint maxComputeImageUniforms = 0;
+                glGetIntegerv(GL_MAX_COMPUTE_IMAGE_UNIFORMS, &maxComputeImageUniforms);
+                GLint maxBufferSize = 0;
+                glGetIntegerv(GL_MAX_TEXTURE_BUFFER_SIZE, &maxBufferSize);
+                while (glGetError() != GL_NO_ERROR) {
+                }
+                return maxImageUnits >= 2 && maxComputeImageUniforms >= 2 && maxBufferSize >= 4;
+            }
+
+            static GLuint MakeComputeProgram(const char* source, std::string* outError) {
+                const GLuint shader = glCreateShader(GL_COMPUTE_SHADER);
+                glShaderSource(shader, 1, &source, nullptr);
+                glCompileShader(shader);
+                GLint compiled = GL_FALSE;
+                glGetShaderiv(shader, GL_COMPILE_STATUS, &compiled);
+                if (compiled == GL_FALSE) {
+                    char log[2048] = {};
+                    glGetShaderInfoLog(shader, sizeof(log) - 1, nullptr, log);
+                    *outError = std::string("compute shader did not compile: ") + log;
+                    glDeleteShader(shader);
+                    return 0;
+                }
+                const GLuint program = glCreateProgram();
+                glAttachShader(program, shader);
+                glLinkProgram(program);
+                glDeleteShader(shader);
+                GLint linked = GL_FALSE;
+                glGetProgramiv(program, GL_LINK_STATUS, &linked);
+                if (linked == GL_FALSE) {
+                    char log[2048] = {};
+                    glGetProgramInfoLog(program, sizeof(log) - 1, nullptr, log);
+                    *outError = std::string("compute program did not link: ") + log;
+                    glDeleteProgram(program);
+                    return 0;
+                }
+                return program;
+            }
+
+            // An R32UI buffer texture over a fresh 4-texel buffer, every texel `fill`.
+            static GLuint MakeBufferTexture(GLuint* outBuffer, GLuint fill) {
+                const GLuint texels[4] = {fill, fill, fill, fill};
+                glGenBuffers(1, outBuffer);
+                glBindBuffer(GL_TEXTURE_BUFFER, *outBuffer);
+                glBufferData(GL_TEXTURE_BUFFER, sizeof(texels), texels, GL_DYNAMIC_COPY);
+                GLuint texture = 0;
+                glGenTextures(1, &texture);
+                glBindTexture(GL_TEXTURE_BUFFER, texture);
+                glTexBuffer(GL_TEXTURE_BUFFER, GL_R32UI, *outBuffer);
+                return texture;
+            }
+
+            static GLuint ReadBufferTexel0(GLuint buffer) {
+                GLuint value = 0xFFFFFFFFu;
+                glBindBuffer(GL_TEXTURE_BUFFER, buffer);
+                glGetBufferSubData(GL_TEXTURE_BUFFER, 0, sizeof(value), &value);
+                return value;
+            }
+
+            GLuint m_vao = 0;
+        };
+
+        // -----------------------------------------------------------------------------------
+        // F-3: a storage redefinition WHILE ATTACHED reaches the framebuffer record
+        // -----------------------------------------------------------------------------------
+        //
+        // GL_SRGB8 is a format Espryt can only render into through its three-channel widening
+        // (llvmpipe reports INCOMPLETE_ATTACHMENT for it natively - ThreeChannelAttachmentScenario
+        // measured the table), so its draw buffer carries the alpha-widened mask: every draw has its
+        // alpha masked off so the stored alpha stays at the 1.0 a three-channel format implies.
+        // Redefine the same attached texture as GL_SRGB8_ALPHA8 and the application owns alpha
+        // again - the mask must clear. On the tree the audit read the record still said SRGB8, the
+        // handle arm kept masking, and the 0.25 this case draws never reached the storage; on the
+        // pre-handle arm the twin regenerated the (mutable) storage on the same driver id, nothing
+        // the FBO memo reads moved, and the masks stayed the same way.
+
+        TEST_F(P4aSeamAuditScenario, ATextureRespecifiedWhileAttachedReachesTheFramebufferRecord) {
+            if (!Ready()) return;
+            SkipUnlessEspryt("F-3");
+            if (IsSkipped()) return;
+
+            std::string error;
+            const GLuint program = CompileProgram(kQuadVS, kColorFS, &error);
+            ASSERT_NE(program, 0u) << error;
+            const GLint colorLocation = glGetUniformLocation(program, "uColor");
+            ASSERT_GE(colorLocation, 0);
+
+            GLuint texture = 0;
+            glGenTextures(1, &texture);
+            glBindTexture(GL_TEXTURE_2D, texture);
+            glTexImage2D(GL_TEXTURE_2D, 0, GL_SRGB8, kSize, kSize, 0, GL_RGB, GL_UNSIGNED_BYTE, nullptr);
+            glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+            glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+            ASSERT_EQ(FirstGLError(), 0u) << "the SRGB8 texture was refused";
+
+            GLuint fbo = 0;
+            glGenFramebuffers(1, &fbo);
+            glBindFramebuffer(GL_FRAMEBUFFER, fbo);
+            glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, texture, 0);
+            ASSERT_EQ(glCheckFramebufferStatus(GL_FRAMEBUFFER), static_cast<GLenum>(GL_FRAMEBUFFER_COMPLETE))
+                << "an SRGB8 colour attachment must be complete (natively or through the widening)";
+            glViewport(0, 0, kSize, kSize);
+            glUseProgram(program);
+            glUniform4f(colorLocation, 0.0f, 1.0f, 0.0f, 0.25f);
+
+            // Phase 1: the three-channel format. Whatever the draw writes, GL reports alpha 1.0.
+            glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
+            glClear(GL_COLOR_BUFFER_BIT);
+            DrawQuad();
+            float pixel[4];
+            glReadBuffer(GL_COLOR_ATTACHMENT0);
+            ReadPixelFloat(kSize / 2, kSize / 2, pixel);
+            EXPECT_NEAR(pixel[3], 1.0f, 0.02f) << "a three-channel attachment reports alpha 1.0";
+
+            // Phase 2: THE RESPECIFY, while attached, with no re-attach and no rebind of the FBO.
+            // The only thing that moves between the two draws is the texture's storage.
+            glBindTexture(GL_TEXTURE_2D, texture);
+            glTexImage2D(GL_TEXTURE_2D, 0, GL_SRGB8_ALPHA8, kSize, kSize, 0, GL_RGBA, GL_UNSIGNED_BYTE, nullptr);
+            ASSERT_EQ(FirstGLError(), 0u) << "the respecify to SRGB8_ALPHA8 was refused";
+            ASSERT_EQ(glCheckFramebufferStatus(GL_FRAMEBUFFER), static_cast<GLenum>(GL_FRAMEBUFFER_COMPLETE));
+
+            glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
+            glClear(GL_COLOR_BUFFER_BIT);
+            DrawQuad();
+            ReadPixelFloat(kSize / 2, kSize / 2, pixel);
+            EXPECT_NEAR(pixel[1], 1.0f, 0.05f) << "the draw did not land at all";
+            // PUSH BUILDS ONLY, EVERY ARM OF THEM. The pre-handle half of the fix (an in-place
+            // regeneration takes the backend-id generation a re-mint takes) is Espryt code the
+            // pull build would share, and G1 keeps the pull library byte-identical to the P4a
+            // baseline - so it is compiled under MOBILEGL_PIPE_PUSH and the pull build keeps the
+            // pre-P4a hole until the same lines land on dev on their own. The peek returns true
+            // exactly where it could look, which for a case that already skipped off Espryt means
+            // "a push build"; what it writes (is the handle arm live) does not matter here.
+            bool framebufferArmLive = false;
+            if (PeekEsprytFramebufferHandleArmIsLive(&framebufferArmLive)) {
+                EXPECT_NEAR(pixel[3], 0.25f, 0.02f)
+                    << "the draw's alpha never reached a four-channel attachment: the framebuffer record "
+                       "(handle arm) or the FBO twin's memo (pre-handle arm) still describes the "
+                       "three-channel storage the texture was attached with, so alpha stayed masked off (F-3)";
+            } else {
+                std::cout << "[ P4aSeamAudit ] texture respecify verdict DECLINED on the pull build (the "
+                             "in-place regeneration bump is push-only by G1); alpha read "
+                          << pixel[3] << std::endl;
+                RecordProperty("p4a_seam_white_box", "declined");
+                RecordProperty("p4a_seam_white_box_reason", "texture respecify: pull build (G1)");
+            }
+
+            glBindFramebuffer(GL_FRAMEBUFFER, 0);
+            glDeleteFramebuffers(1, &fbo);
+            glDeleteTextures(1, &texture);
+            glDeleteProgram(program);
+            EXPECT_EQ(FirstGLError(), 0u) << GLErrorName(FirstGLError());
+        }
+
+        // The renderbuffer twin. A renderbuffer's three storage setters bump no version at all:
+        // D-D2 closed the RESOURCE record by emitting from the entry point and left the framebuffer
+        // record - and with it the masks - describing the storage it was attached with.
+        TEST_F(P4aSeamAuditScenario, ARenderbufferRestoragedWhileAttachedReachesTheFramebufferRecord) {
+            if (!Ready()) return;
+            SkipUnlessEspryt("F-3");
+            if (IsSkipped()) return;
+
+            std::string error;
+            const GLuint program = CompileProgram(kQuadVS, kColorFS, &error);
+            ASSERT_NE(program, 0u) << error;
+            const GLint colorLocation = glGetUniformLocation(program, "uColor");
+            ASSERT_GE(colorLocation, 0);
+
+            GLuint renderbuffer = 0;
+            glGenRenderbuffers(1, &renderbuffer);
+            glBindRenderbuffer(GL_RENDERBUFFER, renderbuffer);
+            glRenderbufferStorage(GL_RENDERBUFFER, GL_SRGB8, kSize, kSize);
+            ASSERT_EQ(FirstGLError(), 0u) << "the SRGB8 renderbuffer was refused";
+
+            GLuint fbo = 0;
+            glGenFramebuffers(1, &fbo);
+            glBindFramebuffer(GL_FRAMEBUFFER, fbo);
+            glFramebufferRenderbuffer(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_RENDERBUFFER, renderbuffer);
+            ASSERT_EQ(glCheckFramebufferStatus(GL_FRAMEBUFFER), static_cast<GLenum>(GL_FRAMEBUFFER_COMPLETE))
+                << "an SRGB8 renderbuffer attachment must be complete (natively or through the widening)";
+            glViewport(0, 0, kSize, kSize);
+            glUseProgram(program);
+            glUniform4f(colorLocation, 0.0f, 1.0f, 0.0f, 0.25f);
+
+            glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
+            glClear(GL_COLOR_BUFFER_BIT);
+            DrawQuad();
+            float pixel[4];
+            glReadBuffer(GL_COLOR_ATTACHMENT0);
+            ReadPixelFloat(kSize / 2, kSize / 2, pixel);
+            EXPECT_NEAR(pixel[3], 1.0f, 0.02f) << "a three-channel attachment reports alpha 1.0";
+
+            // THE RE-STORAGE, while attached.
+            glBindRenderbuffer(GL_RENDERBUFFER, renderbuffer);
+            glRenderbufferStorage(GL_RENDERBUFFER, GL_SRGB8_ALPHA8, kSize, kSize);
+            ASSERT_EQ(FirstGLError(), 0u) << "the re-storage to SRGB8_ALPHA8 was refused";
+            ASSERT_EQ(glCheckFramebufferStatus(GL_FRAMEBUFFER), static_cast<GLenum>(GL_FRAMEBUFFER_COMPLETE));
+
+            glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
+            glClear(GL_COLOR_BUFFER_BIT);
+            DrawQuad();
+            ReadPixelFloat(kSize / 2, kSize / 2, pixel);
+            EXPECT_NEAR(pixel[1], 1.0f, 0.05f) << "the draw did not land at all";
+            // THE HANDLE ARM ONLY. On the pre-handle arm a renderbuffer's twin is reached only from
+            // inside the FBO walk, and nothing that walk's memo reads moves on glRenderbufferStorage
+            // - the frontend setters bump no version (D-D2), no framebuffer version sees them, and
+            // the twin that would bump the backend generation is exactly what the memo skips. That
+            // is pre-P4a code and D-D2's documented hole; the resource record is what closes it,
+            // so the verdict is taken where the record is consumed and declined by name elsewhere
+            // (measured: alpha 1.0 on the pull build and at 0x1ff / 0, the mask of the storage the
+            // renderbuffer was attached with).
+            bool framebufferArmLive = false;
+            if (PeekEsprytFramebufferHandleArmIsLive(&framebufferArmLive) && framebufferArmLive) {
+                EXPECT_NEAR(pixel[3], 0.25f, 0.02f)
+                    << "the draw's alpha never reached the four-channel renderbuffer: the framebuffer "
+                       "record still describes the storage it was attached with (F-3)";
+            } else {
+                std::cout << "[ P4aSeamAudit ] renderbuffer re-storage verdict DECLINED on the pre-handle arm "
+                             "(D-D2's documented hole: no frontend version and no backend generation moves on a "
+                             "renderbuffer re-storage until the FBO walk the memo skips); alpha read "
+                          << pixel[3] << std::endl;
+                RecordProperty("p4a_seam_white_box", "declined");
+                RecordProperty("p4a_seam_white_box_reason", "renderbuffer re-storage: pre-handle arm (D-D2)");
+            }
+
+            glBindFramebuffer(GL_FRAMEBUFFER, 0);
+            glDeleteFramebuffers(1, &fbo);
+            glDeleteRenderbuffers(1, &renderbuffer);
+            glDeleteProgram(program);
+            EXPECT_EQ(FirstGLError(), 0u) << GLErrorName(FirstGLError());
+        }
+
+        // The mirror direction, four channels -> three, and it needs the driver to READ the stored
+        // alpha because the readback fixup (which consults the frontend) would hide it: after the
+        // respecify to SRGB8 the widening discipline has to hold - the clear puts 1.0 into the
+        // carrier's alpha and the draw is masked away from it - so a GL_DST_ALPHA blend of white sees
+        // 1.0. On a stale record the draw wrote its 0.25 into the carrier and the blend saw that.
+        TEST_F(P4aSeamAuditScenario, ATextureRespecifiedToThreeChannelsWhileAttachedReachesTheFramebufferRecord) {
+            if (!Ready()) return;
+            SkipUnlessEspryt("F-3");
+            if (IsSkipped()) return;
+
+            std::string error;
+            const GLuint program = CompileProgram(kQuadVS, kColorFS, &error);
+            ASSERT_NE(program, 0u) << error;
+            const GLint colorLocation = glGetUniformLocation(program, "uColor");
+            ASSERT_GE(colorLocation, 0);
+
+            GLuint texture = 0;
+            glGenTextures(1, &texture);
+            glBindTexture(GL_TEXTURE_2D, texture);
+            glTexImage2D(GL_TEXTURE_2D, 0, GL_SRGB8_ALPHA8, kSize, kSize, 0, GL_RGBA, GL_UNSIGNED_BYTE, nullptr);
+            glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+            glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+            ASSERT_EQ(FirstGLError(), 0u) << "the SRGB8_ALPHA8 texture was refused";
+
+            GLuint fbo = 0;
+            glGenFramebuffers(1, &fbo);
+            glBindFramebuffer(GL_FRAMEBUFFER, fbo);
+            glFramebufferTexture2D(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, texture, 0);
+            ASSERT_EQ(glCheckFramebufferStatus(GL_FRAMEBUFFER), static_cast<GLenum>(GL_FRAMEBUFFER_COMPLETE));
+            glViewport(0, 0, kSize, kSize);
+            glUseProgram(program);
+
+            // Phase 1: four channels, the application owns alpha.
+            glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
+            glClear(GL_COLOR_BUFFER_BIT);
+            glUniform4f(colorLocation, 0.0f, 1.0f, 0.0f, 0.25f);
+            DrawQuad();
+            float pixel[4];
+            glReadBuffer(GL_COLOR_ATTACHMENT0);
+            ReadPixelFloat(kSize / 2, kSize / 2, pixel);
+            EXPECT_NEAR(pixel[3], 0.25f, 0.02f) << "a four-channel attachment stores the draw's alpha";
+
+            // Phase 2: THE RESPECIFY to three channels, while attached.
+            glBindTexture(GL_TEXTURE_2D, texture);
+            glTexImage2D(GL_TEXTURE_2D, 0, GL_SRGB8, kSize, kSize, 0, GL_RGB, GL_UNSIGNED_BYTE, nullptr);
+            ASSERT_EQ(FirstGLError(), 0u) << "the respecify to SRGB8 was refused";
+            ASSERT_EQ(glCheckFramebufferStatus(GL_FRAMEBUFFER), static_cast<GLenum>(GL_FRAMEBUFFER_COMPLETE));
+
+            glDisable(GL_BLEND);
+            glClearColor(0.0f, 0.0f, 0.0f, 0.0f);
+            glClear(GL_COLOR_BUFFER_BIT);
+            glUniform4f(colorLocation, 0.0f, 1.0f, 0.0f, 0.25f);
+            DrawQuad();
+            // dst = stored alpha; src factor GL_DST_ALPHA, dst factor GL_ZERO, source white =>
+            // the colour becomes (storedAlpha, storedAlpha, storedAlpha) - ThreeChannelAttachment's
+            // own probe, which nothing on the readback path can doctor.
+            glEnable(GL_BLEND);
+            glBlendFunc(GL_DST_ALPHA, GL_ZERO);
+            glUniform4f(colorLocation, 1.0f, 1.0f, 1.0f, 1.0f);
+            DrawQuad();
+            glDisable(GL_BLEND);
+            ReadPixelFloat(kSize / 2, kSize / 2, pixel);
+            // PUSH BUILDS ONLY, EVERY ARM OF THEM (the mirror). The pre-handle half of the fix (an in-place
+            // regeneration takes the backend-id generation a re-mint takes) is Espryt code the
+            // pull build would share, and G1 keeps the pull library byte-identical to the P4a
+            // baseline - so it is compiled under MOBILEGL_PIPE_PUSH and the pull build keeps the
+            // pre-P4a hole until the same lines land on dev on their own. The peek returns true
+            // exactly where it could look, which for a case that already skipped off Espryt means
+            // "a push build"; what it writes (is the handle arm live) does not matter here.
+            bool framebufferArmLive = false;
+            if (PeekEsprytFramebufferHandleArmIsLive(&framebufferArmLive)) {
+                EXPECT_NEAR(pixel[0], 1.0f, 0.05f)
+                    << "GL_DST_ALPHA read the stored alpha of a three-channel attachment and it was not "
+                       "1.0: the framebuffer record (handle arm) or the FBO twin's memo (pre-handle arm) "
+                       "still describes the four-channel storage the texture was attached with, so the "
+                       "draw was let write alpha (F-3, mirror)";
+            } else {
+                std::cout << "[ P4aSeamAudit ] three-channel respecify verdict DECLINED on the pull build (the "
+                             "in-place regeneration bump is push-only by G1); red read "
+                          << pixel[0] << std::endl;
+                RecordProperty("p4a_seam_white_box", "declined");
+                RecordProperty("p4a_seam_white_box_reason", "three-channel respecify: pull build (G1)");
+            }
+
+            glBindFramebuffer(GL_FRAMEBUFFER, 0);
+            glDeleteFramebuffers(1, &fbo);
+            glDeleteTextures(1, &texture);
+            glDeleteProgram(program);
+            EXPECT_EQ(FirstGLError(), 0u) << GLErrorName(FirstGLError());
+        }
+
+        // -----------------------------------------------------------------------------------
+        // F-1 / F-1b: a program switch re-resolves the view set, and the texture sync list with it
+        // -----------------------------------------------------------------------------------
+        //
+        // The sequence the audit named, and every step of it is ordinary: two programs sampling two
+        // different units, a texture bound to a unit's EMPTY 2D slot - the unit was already touched
+        // through another target, so the high-water mark does not move - while a program that does
+        // not sample it is in use, then the switch to the one that does. Nothing between the two
+        // draws touches a parameter, a level or a populated slot, which is exactly what leaves the
+        // record epoch - and the program-independent texture sync list keyed on it - unmoved on
+        // the tree the audit read: the second program sampled an unbound unit and drew black.
+        TEST_F(P4aSeamAuditScenario, ATextureBoundToAnEmptySlotUnderOneProgramIsSampledByTheNext) {
+            if (!Ready()) return;
+
+            std::string error;
+            const GLuint first = CompileProgram(kQuadVS, kFetchFS, &error);
+            ASSERT_NE(first, 0u) << error;
+            const GLuint second = CompileProgram(kQuadVS, kFetchFS, &error);
+            ASSERT_NE(second, 0u) << error;
+            glUseProgram(first);
+            glUniform1i(glGetUniformLocation(first, "uTex"), 0);
+            glUseProgram(second);
+            glUniform1i(glGetUniformLocation(second, "uTex"), 1);
+            glUseProgram(0);
+
+            // Every texture exists, complete, with its parameters set, BEFORE the first draw: a
+            // parameter or a level defined between the two draws would move the sampling-resolution
+            // generation and rescue the list by accident.
+            const GLuint red = MakeSolidTexture2D(255, 0, 0);
+            const GLuint green = MakeSolidTexture2D(0, 255, 0);
+            GLuint touch3D = 0;
+            glGenTextures(1, &touch3D);
+            glBindTexture(GL_TEXTURE_3D, touch3D);
+            const std::uint8_t blue[2 * 2 * 2 * 4] = {0, 0, 255, 255, 0, 0, 255, 255, 0, 0, 255, 255, 0, 0, 255, 255,
+                                                     0, 0, 255, 255, 0, 0, 255, 255, 0, 0, 255, 255, 0, 0, 255, 255};
+            glTexImage3D(GL_TEXTURE_3D, 0, GL_RGBA8, 2, 2, 2, 0, GL_RGBA, GL_UNSIGNED_BYTE, blue);
+            glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+            glTexParameteri(GL_TEXTURE_3D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+            glBindTexture(GL_TEXTURE_3D, 0);
+            glBindTexture(GL_TEXTURE_2D, 0);
+            ASSERT_EQ(FirstGLError(), 0u) << "texture setup left a GL error behind";
+
+            ColorFbo target = MakeColorFbo(kSize, kSize);
+            ASSERT_NE(target.fbo, 0u);
+            BindFbo(target);
+            glBindVertexArray(m_vao);
+
+            // Unit 1 is TOUCHED through its 3D slot; its 2D slot stays empty. Unit 0 holds red.
+            // The first program is in use BEFORE the first verb (the clear), so the very first
+            // view set that goes out is already resolved for it - measured: with no program in
+            // use at the clear the first set is [null, null], and the bind below then re-resolves
+            // to [red, null], a DIFFERENT set that moves the serial and rescues the case by
+            // accident.
+            glActiveTexture(GL_TEXTURE1);
+            glBindTexture(GL_TEXTURE_3D, touch3D);
+            glActiveTexture(GL_TEXTURE0);
+            glBindTexture(GL_TEXTURE_2D, red);
+            glUseProgram(first);
+            ClearTo(0.0f, 0.0f, 1.0f, 1.0f);
+            DrawQuad();
+
+            // THE BIND ONTO THE EMPTY SLOT, under a program that does not sample unit 1, and a
+            // draw with THAT program so the bind's own re-resolution of the view set happens under
+            // it (the bind generation fires bit 12 at the next verb; a switch inside the same verb
+            // gap would let that fire resolve under the second program by accident) ...
+            glActiveTexture(GL_TEXTURE1);
+            glBindTexture(GL_TEXTURE_2D, green);
+            glActiveTexture(GL_TEXTURE0);
+            DrawQuad();
+            // ... and THE SWITCH to the one that does sample it. No other state moves.
+            glUseProgram(second);
+            DrawQuad();
+            EXPECT_EQ(FirstGLError(), 0u) << "the two draws left a GL error behind";
+
+            const Image image = ReadPixels(kSize, kSize);
+            ASSERT_FALSE(image.Empty());
+            EXPECT_TRUE(RegionIsMostly(image, kInset, kSize - 1 - kInset, kInset, kSize - 1 - kInset, "green", 0.0,
+                                       "the draw after the program switch"))
+                << "black means the second program sampled an unbound unit: the texture bound to the "
+                   "empty slot was never synced because the view set - and E's record epoch with it - "
+                   "did not move on the program switch (F-1 / F-1b); red means the first program's "
+                   "set was still in force";
+
+            glActiveTexture(GL_TEXTURE1);
+            glBindTexture(GL_TEXTURE_2D, 0);
+            glBindTexture(GL_TEXTURE_3D, 0);
+            glActiveTexture(GL_TEXTURE0);
+            glBindTexture(GL_TEXTURE_2D, 0);
+            glUseProgram(0);
+            DestroyColorFbo(target);
+            glDeleteTextures(1, &red);
+            glDeleteTextures(1, &green);
+            glDeleteTextures(1, &touch3D);
+            glDeleteProgram(first);
+            glDeleteProgram(second);
+            EXPECT_EQ(FirstGLError(), 0u) << GLErrorName(FirstGLError());
+        }
+
+        // -----------------------------------------------------------------------------------
+        // F-2 / SD-4: the image window follows the program, through buffer images
+        // -----------------------------------------------------------------------------------
+        //
+        // Public-GL half: both dispatches store what they should (every arm passes this - the
+        // server's window/high-water union takes the pre-handle bind for a unit the record does
+        // not cover, which is exactly why the seam was silent). White-box half, on Espryt's handle
+        // arm: after the first dispatch set_shader_images must have arrived with a window of ONE
+        // unit (SD-4: on the tree the audit read a buffer image never reached the record at all -
+        // the null -> program transition moved nothing bit 14 read), and after the switch to the
+        // program naming two units the window must be TWO (F-2: the two programs' image-unit
+        // counters are equal, so the switch alone moved nothing either).
+        TEST_F(P4aSeamAuditScenario, AProgramSwitchWithEqualImageUnitCountersMovesTheImageWindow) {
+            if (!Ready()) return;
+            if (!ComputeImagesAreUsable()) GTEST_SKIP() << "no compute image units / buffer textures on this host";
+
+            std::string error;
+            const GLuint one = MakeComputeProgram(kOneBufferImageCS, &error);
+            ASSERT_NE(one, 0u) << error;
+            const GLuint two = MakeComputeProgram(kTwoBufferImagesCS, &error);
+            ASSERT_NE(two, 0u) << error;
+
+            GLuint buffer0 = 0;
+            GLuint buffer1 = 0;
+            const GLuint image0 = MakeBufferTexture(&buffer0, 0u);
+            const GLuint image1 = MakeBufferTexture(&buffer1, 0u);
+            ASSERT_EQ(FirstGLError(), 0u) << "buffer texture setup left a GL error behind";
+
+            // Both units bound BEFORE any dispatch, so the bind generation does not move between
+            // the two dispatches and the only thing that changes is the program in use.
+            glBindImageTexture(0, image0, 0, GL_FALSE, 0, GL_READ_WRITE, GL_R32UI);
+            glBindImageTexture(1, image1, 0, GL_FALSE, 0, GL_READ_WRITE, GL_R32UI);
+            ASSERT_EQ(FirstGLError(), 0u) << "binding the buffer images left a GL error behind";
+
+            const bool whiteBox = SamplerHandleArmIsLive("F-2 / SD-4");
+
+            glUseProgram(one);
+            glDispatchCompute(1, 1, 1);
+            glMemoryBarrier(GL_ALL_BARRIER_BITS);
+            EXPECT_EQ(FirstGLError(), 0u) << "the first dispatch leaked a GL error";
+            if (whiteBox) {
+                PipeShaderImageWindowPeek window{};
+                ASSERT_TRUE(PeekPipeShaderImageWindow(&window));
+                EXPECT_EQ(window.Start, 0u);
+                EXPECT_EQ(window.Count, 1u)
+                    << "set_shader_images never arrived for a program whose only image is a BUFFER "
+                       "image (SD-4): the null -> program transition moved nothing bit 14 read";
+            }
+
+            glUseProgram(two);
+            glDispatchCompute(1, 1, 1);
+            glMemoryBarrier(GL_ALL_BARRIER_BITS);
+            EXPECT_EQ(FirstGLError(), 0u) << "the second dispatch leaked a GL error";
+            if (whiteBox) {
+                PipeShaderImageWindowPeek window{};
+                ASSERT_TRUE(PeekPipeShaderImageWindow(&window));
+                EXPECT_EQ(window.Start, 0u);
+                EXPECT_EQ(window.Count, 2u)
+                    << "the image window did not follow the program switch: two programs with equal "
+                       "image-unit counters, and bit 14 mixed only the counter (F-2)";
+            }
+
+            EXPECT_EQ(ReadBufferTexel0(buffer0), 7u) << "the first program's store did not land";
+            EXPECT_EQ(ReadBufferTexel0(buffer1), 9u) << "the second program's store did not land";
+
+            glBindImageTexture(0, 0, 0, GL_FALSE, 0, GL_READ_ONLY, GL_R32UI);
+            glBindImageTexture(1, 0, 0, GL_FALSE, 0, GL_READ_ONLY, GL_R32UI);
+            glBindBuffer(GL_TEXTURE_BUFFER, 0);
+            glBindTexture(GL_TEXTURE_BUFFER, 0);
+            glUseProgram(0);
+            glDeleteProgram(one);
+            glDeleteProgram(two);
+            glDeleteTextures(1, &image0);
+            glDeleteTextures(1, &image1);
+            glDeleteBuffers(1, &buffer0);
+            glDeleteBuffers(1, &buffer1);
+            EXPECT_EQ(FirstGLError(), 0u) << GLErrorName(FirstGLError());
+        }
+
+        // -----------------------------------------------------------------------------------
+        // F-4: the unit's driver sampler is the CSO's own twin on the handle arm
+        // -----------------------------------------------------------------------------------
+        //
+        // Public-GL half: a glBindSampler'd object whose wrap differs from the texture's built-in
+        // sampler wins (GL 4.6 core 8.10) - every arm passes this, because the pre-handle program
+        // pass bound the object through its identity twin. White-box half, on Espryt's handle arm:
+        // the sampler the unit carries on the driver must be the twin Espryt holds AT THE CSO
+        // HANDLE bind_sampler_states named for the unit. On the tree the audit read that twin did
+        // not exist - the handle is content-addressed, the registry's twins were minted off
+        // lifetime ids - so the record arm bound nothing on every draw.
+        TEST_F(P4aSeamAuditScenario, ABoundSamplerObjectIsDrivenThroughItsCsoTwinOnTheHandleArm) {
+            if (!Ready()) return;
+
+            std::string error;
+            const GLuint program = CompileProgram(kQuadVS, kOutsideSampleFS, &error);
+            ASSERT_NE(program, 0u) << error;
+
+            // The texture's built-in sampler REPEATS, so (1.5, 1.5) reads the red texel through it;
+            // the sampler object CLAMPS TO A WHITE BORDER, so the same coordinate reads white
+            // through it. White is a Vulkan palette border colour, so Magma needs no extension.
+            const GLuint red = MakeSolidTexture2D(255, 0, 0);
+            glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
+            glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
+            GLuint sampler = 0;
+            glGenSamplers(1, &sampler);
+            glSamplerParameteri(sampler, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+            glSamplerParameteri(sampler, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+            glSamplerParameteri(sampler, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_BORDER);
+            glSamplerParameteri(sampler, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_BORDER);
+            const GLfloat white[4] = {1.0f, 1.0f, 1.0f, 1.0f};
+            glSamplerParameterfv(sampler, GL_TEXTURE_BORDER_COLOR, white);
+            ASSERT_EQ(FirstGLError(), 0u) << "sampler setup left a GL error behind";
+
+            ColorFbo target = MakeColorFbo(kSize, kSize);
+            ASSERT_NE(target.fbo, 0u);
+            BindFbo(target);
+            glBindVertexArray(m_vao);
+            glActiveTexture(GL_TEXTURE0);
+            glBindTexture(GL_TEXTURE_2D, red);
+            glBindSampler(0, sampler);
+            glUseProgram(program);
+            glUniform1i(glGetUniformLocation(program, "uTex"), 0);
+            ClearTo(0.0f, 0.0f, 1.0f, 1.0f);
+            DrawQuad();
+            EXPECT_EQ(FirstGLError(), 0u) << "the draw left a GL error behind";
+
+            const Image image = ReadPixels(kSize, kSize);
+            ASSERT_FALSE(image.Empty());
+            EXPECT_TRUE(RegionIsMostly(image, kInset, kSize - 1 - kInset, kInset, kSize - 1 - kInset, "white", 0.0,
+                                       "the draw through the bound sampler object"))
+                << "red means the texture's own REPEAT sampler applied instead of the bound object's "
+                   "CLAMP_TO_BORDER";
+
+            if (SamplerHandleArmIsLive("F-4")) {
+                EsprytUnitSamplerPeek peek{};
+                ASSERT_TRUE(PeekEsprytUnitSampler(0, sampler, &peek));
+                std::cout << "[ P4aSeamAudit ] white-box: unit 0 driver sampler " << peek.BoundSamplerId
+                          << ", bind_sampler_states handle {" << peek.CsoHandleSlot << ", " << peek.CsoHandleGen
+                          << "} inside window " << (peek.UnitInsideWindow ? "yes" : "no") << ", CSO twin "
+                          << peek.CsoTwinSamplerId << ", identity twin " << peek.IdentityTwinSamplerId << std::endl;
+                EXPECT_TRUE(peek.UnitInsideWindow) << "bind_sampler_states did not describe unit 0";
+                EXPECT_NE(peek.CsoHandleSlot, 0u) << "bind_sampler_states names no CSO for a unit that carries "
+                                                     "a sampler object";
+                EXPECT_NE(peek.CsoTwinSamplerId, 0u)
+                    << "Espryt holds no twin at the CSO handle bind_sampler_states named: the record arm's "
+                       "lookup went to the identity-keyed registry with a content-addressed handle and "
+                       "could never hit (F-4)";
+                EXPECT_EQ(peek.BoundSamplerId, peek.CsoTwinSamplerId)
+                    << "the driver sampler on unit 0 is not the CSO's twin, so it was put there by the "
+                       "pre-handle program pass and not by the record arm (F-4)";
+                EXPECT_EQ(peek.IdentityTwinSamplerId, 0u)
+                    << "an identity-keyed twin was minted for the sampler object on the handle arm: the "
+                       "pre-handle pass is still the one doing the binding";
+            }
+
+            glBindSampler(0, 0);
+            glBindTexture(GL_TEXTURE_2D, 0);
+            glUseProgram(0);
+            DestroyColorFbo(target);
+            glDeleteSamplers(1, &sampler);
+            glDeleteTextures(1, &red);
+            glDeleteProgram(program);
+            EXPECT_EQ(FirstGLError(), 0u) << GLErrorName(FirstGLError());
+        }
+
+    } // namespace
+} // namespace MGITest

MobileGL/MG_IntegrationTest/Scenarios/TextureParamsWithoutASamplerViewScenario.cpp

@@ -0,0 +1,775 @@
+// MobileGL - MobileGL/MG_IntegrationTest/Scenarios/TextureParamsWithoutASamplerViewScenario.cpp
+// Copyright (c) 2026 MobileGL-Dev
+// Licensed under the GNU Lesser General Public License v3.0:
+//   https://www.gnu.org/licenses/gpl-3.0.txt
+//   https://www.gnu.org/licenses/lgpl-3.0.txt
+// SPDX-License-Identifier: LGPL-3.0-only
+// End of Source File Header
+//
+// Scenario - A TEXTURE'S PARAMETERS TAKE EFFECT EVEN WHEN IT HAS NO SAMPLER VIEW (gate G9), the
+// one scenario ROADMAP.md:20 names by hand and requires to be RED before P4a lands.
+//
+// THE DESIGN STATEMENT IT TESTS, ARCHITECTURE.md:100 (D10), verbatim: "SetTextureParams 按资源寻址、
+// 与 sampler view 分开（D10）：只作 FBO attachment / image 单元 / glCopyImageSubData 端点的纹理没有
+// sampler view，但 Espryt 对 attachment 也同步纹理参数，且 RequireImageBindableStorage 需要在前端参数
+// 版本不动时强制重同步." A texture that is only an attachment, only an image-unit binding or only a
+// copy endpoint has NO sampler view at all - so a design that carried texture parameters on the
+// view would silently drop them for exactly those textures. P4a addresses set_texture_params by
+// RESOURCE, independently of any binding, which is what makes the record exist for every texture
+// the moment its parameters move.
+//
+// THE FOUR CASES, and BRIEF-P4A.md D-E3 is where their expected verdicts come from:
+//
+//   AnAttachmentOnlyTexturesSwizzleReachesTheDriver                        green today, green after
+//   AReadAttachmentOnlyTexturesDepthStencilModeReachesTheDriver            D-E3 says RED today
+//   AnImageUnitOnlyTexturesSwizzleSurvivesARequireImageBindableStorageRemint green today, green after
+//   ACopyImageEndpointOnlyTexturesParamsReachTheDriver                     green today, green after
+//
+// [MEASURED, AND IT DOES NOT MATCH D-E3] All four are GREEN on the P4a contract commit (08192d72),
+// on llvmpipe, in the push build. The second one is green FOR A REASON THAT IS ITSELF THE FINDING,
+// and it is written here rather than in a review comment because the next person to try to make it
+// red needs to know why they cannot:
+//
+//   A texture parameter's only public-GL observable is a SAMPLE - nothing about an attachment, an
+//   image binding or a copy endpoint reads a swizzle or an aspect mode - and a sample puts the
+//   texture on SyncNeccessaryTextures' UNIT list. That walk calls SyncTextureParamsToBackend for
+//   every entry whose IsDrawSyncClean is false (DirectGLES.cpp:1896-1898), and IsDrawSyncClean is
+//   false whenever the frontend's parameter version has moved since the last sync
+//   (Managers.h:1399-1416, `m_syncedTextureParamsVersion != paramsVersion`). So the very act of
+//   observing the parameter repairs the state the observation was meant to catch: the gap between
+//   "the parameter moved on a read-attachment-only texture" and "the driver was told" is REAL, and
+//   it is closed by the next sampler binding, which is also the only thing that can see it.
+//
+// What that means for the gate, stated plainly so nobody reads a green here as evidence of
+// anything it is not:
+//
+//   * the four cases are a REGRESSION NET around D10, not the evidence for the change. They pin
+//     the design statement: a texture's parameters take effect however the texture is reached, and
+//     in particular they would go RED if any of the four reachability paths were ever made to
+//     depend on the texture having a sampler VIEW - which is exactly the coupling P4a's
+//     resource-addressed set_texture_params removes and the thing a later phase could reintroduce;
+//   * the "落地前必须红" artefact ROADMAP.md:20 asks for is NOT produced by the public-GL half
+//     of this file, and no public-GL integration scenario on a monolith tree can produce it.
+//     Producing it needs an observation of the DRIVER's texture object taken while the texture is
+//     still read-attachment-only. ID-19 rules that G9 is therefore a WHITE-BOX assertion, and this
+//     file now carries the SCENARIO half of it (the unit half is package D's,
+//     MG_Test/SanityTest.cpp's DirectGLESTextureSync.AnAttachmentOnlyTexturesParametersReachThe
+//     DriverWithNoSamplerView).
+//
+// THE WHITE-BOX HALF, and what it adds to the four cases below. Each case, at the point where its
+// texture is reachable ONLY its own way and BEFORE the observing sample, takes three readings
+// through MG_IntegrationTest/Harness/PipeApplyPeek.h and asserts all three:
+//
+//   (a) the APPLIER holds a set_texture_params record for this texture, at a non-zero ParamsSerial,
+//       carrying the field the case moved;
+//   (b) ESPRYT's applied value for the same texture - read back from the DRIVER, through the twin's
+//       own ES name - is that value ALREADY, not after the first sampler view;
+//   (c) Espryt holds NO SAMPLER VIEW for this texture yet, which is what turns (b) from "applied"
+//       into "applied WITHOUT one" and is the whole claim D10 makes.
+//
+// (c) is the assertion the public-GL half structurally cannot make: making it there would create
+// the view. (b) is the half that goes red on a backend that DEFERS - a tree where the parameter
+// push is gated on a sampler view existing is green on all four public-GL cases forever, because
+// the sample that observes the parameter is also what mints the view and repairs the state.
+//
+// WHAT THE THREE READINGS DO **NOT** COVER, so the next reader does not over-trust them
+// (esprytobj re-review N-9, carried here by request). D's unit probe drives
+// SyncTextureParamsToBackend directly, so the only deferral shape IT can see is one INSIDE that
+// function. These three run through the real per-frame paths and therefore also see a deferral
+// introduced ABOVE it - in SyncNeccessaryTextures, in the attachment walk, or in E's per-unit walk.
+// Between them the two halves cover both, and neither covers both alone.
+//
+// A READING THAT CANNOT BE TAKEN IS DECLINED BY NAME AND THE CASE CONTINUES - it is not a
+// GTEST_SKIP, and that is a deliberate departure from the shape the review sketched. These four
+// cases are dual-purpose: they are also the END-TO-END regression net around D10, and that net is
+// the ONLY thing measuring D10 on exactly the arms where the peek cannot look (the pull build,
+// which has no applier at all; the 0x1ff and 0 lanes, where the texture family is switched off;
+// Magma, which has no Espryt twin). Skipping the case there would delete the one verdict those
+// lanes carry in order to report the absence of a second one. The decline is printed, recorded as
+// a test property and named, so a lane that silently stopped taking the reading is visible in the
+// log rather than in a count.
+//
+// WHY THE SECOND ONE IS THE RED, mechanically (scout-espryt-framebuffer.md 2.6, re-opened at the
+// base ref). Today a texture's parameters ride on the UNIT BINDING and on the DRAW attachment set:
+//
+//   bound to a sampler unit <= the high-water mark  SyncNeccessaryTextures' unit list   -> synced
+//   attachment of the DRAW framebuffer              SyncNeccessaryTextures' FBO list    -> synced
+//   attachment of the READ framebuffer ONLY         SyncCurrentFBO -> SyncToBackend ->
+//                                                   SyncAttachmentObject, which calls
+//                                                   SyncMipmapsToBackend at Managers.cpp:7161
+//                                                   and NOTHING ELSE                    -> NOT synced
+//   bound to an image unit                          SyncImageTextureBinding ->
+//                                                   SyncTextureObjectToBackend, and
+//                                                   RequireImageBindableStorage additionally
+//                                                   forces m_forceTextureParamsResync    -> synced
+//   a glCopyImageSubData endpoint                   MakeGLESCopyImageEndpoint ->
+//                                                   SyncTextureObjectToBackend           -> synced
+//
+// SyncNeccessaryTextures' attachment list reads GetFramebufferBindingSlotChecked(Draw) only
+// (DirectGLES.cpp:1944), so a texture that is exclusively a READ attachment gets its STORAGE synced
+// and its PARAMETERS never. P4a closes that gap deliberately (D-E3): the record is addressed by
+// resource, and Espryt's SyncAttachmentObject applies parameters for ANY attachment, draw or read.
+// It is a behaviour change and it is the deliverable, not a drive-by dev fix (ROADMAP.md:98).
+//
+// HOW EACH CASE OBSERVES "REACHED THE DRIVER", and why the observation is always a LATER SAMPLE.
+// A texture parameter is by definition a sampling parameter: nothing about an attachment, an image
+// binding or a copy endpoint reads a swizzle or a depth/stencil aspect mode, so the only thing that
+// can see one is a sample. Each case therefore does the same three things -
+//
+//   1. put the texture through ONE of the five reachability paths above, and only that one,
+//   2. move a parameter while it is reachable ONLY that way (through the DSA entry points
+//      glTextureParameteri / glTextureSubImage2D, so no step of the setup ever binds the texture to
+//      a sampler unit - a bind would put it on the unit list and answer the question by accident),
+//   3. sample it once, at the end, and read the colour back.
+//
+// - and the difference between them is step 1 alone. A case that is red says: the parameter set
+// while the texture was reachable only that way did not survive to the sample.
+//
+// DIRECTGLES ONLY. The gap is Espryt's - it is a statement about SyncAttachmentObject and
+// SyncNeccessaryTextures - and P4a does not touch MG_Backend/DirectVulkan (D-Q). Magma answers the
+// same GL question through an entirely different path, so a red or a green there would be evidence
+// about P7's work rather than about this gate; the cases SKIP on any other backend, naming that.
+
+#include <cstdint>
+#include <cstdlib>
+#include <iostream>
+#include <string>
+#include <vector>
+
+#include "../Harness/HeadlessGL.h"
+#include "../Harness/PipeApplyPeek.h"
+#include "../Harness/ScenarioFixture.h"
+
+#ifdef GLAPI
+#undef GLAPI
+#endif
+#define GL_GLEXT_PROTOTYPES
+#include <GL/gl.h>
+#include <GL/glcorearb.h>
+#undef GL_GLEXT_PROTOTYPES
+
+namespace MGITest {
+    namespace {
+
+        constexpr int kInset = 2;
+        constexpr int kTextureSize = 4;
+
+        constexpr const char* kQuadVS = R"(#version 330 core
+in vec2 aPos;
+out vec2 vUv;
+void main() {
+    vUv = aPos * 0.5 + 0.5;
+    gl_Position = vec4(aPos, 0.0, 1.0);
+}
+)";
+
+        // Samples texel (0,0) with an explicit fetch: no filtering, no derivatives, no wrap - so
+        // the colour that comes back is the texel as the driver's swizzle presents it and nothing
+        // else can move it.
+        constexpr const char* kFetchFS = R"(#version 330 core
+uniform sampler2D uTex;
+out vec4 oColor;
+void main() { oColor = texelFetch(uTex, ivec2(0, 0), 0); }
+)";
+
+        // The stencil aspect of a packed depth/stencil texture is an UNSIGNED INTEGER texture, so
+        // it needs a usampler2D. The case that uses it turns "the stencil value is what was
+        // cleared" into a colour, because a colour is the only thing this harness can read back.
+        constexpr const char* kStencilFetchFS = R"(#version 330 core
+uniform usampler2D uTex;
+uniform uint uExpected;
+out vec4 oColor;
+void main() {
+    uint value = texelFetch(uTex, ivec2(0, 0), 0).r;
+    oColor = (value == uExpected) ? vec4(0.0, 1.0, 0.0, 1.0) : vec4(1.0, 0.0, 0.0, 1.0);
+}
+)";
+
+        struct Vertex {
+            float x, y;
+        };
+
+        class TextureParamsWithoutASamplerViewScenario : public ScenarioTest {
+        protected:
+            void SetUp() override {
+                ScenarioTest::SetUp();
+                if (!Ready()) return;
+                if (Gl().BackendName() != "DirectGLES") {
+                    GTEST_SKIP() << "DirectGLES only: this scenario is about Espryt's own reachability "
+                                    "table - SyncNeccessaryTextures' attachment list walks the DRAW "
+                                    "slot only (DirectGLES.cpp:1944) and SyncAttachmentObject syncs "
+                                    "storage and not parameters (Managers.cpp:7161). "
+                                 << Gl().BackendName()
+                                 << " answers the same GL question through a different path, so a "
+                                    "verdict here would be evidence about that backend rather than "
+                                    "about this gate (P4a touches no DirectVulkan source but "
+                                    "MagmaPipeArms.h, D-Q).";
+                }
+                std::string error;
+                m_fetchProgram = CompileProgram(kQuadVS, kFetchFS, &error);
+                ASSERT_NE(m_fetchProgram, 0u) << error;
+
+                static const Vertex quad[6] = {{-1.0f, -1.0f}, {1.0f, -1.0f}, {1.0f, 1.0f},
+                                               {-1.0f, -1.0f}, {1.0f, 1.0f},  {-1.0f, 1.0f}};
+                glGenBuffers(1, &m_quadBuffer);
+                glBindBuffer(GL_ARRAY_BUFFER, m_quadBuffer);
+                glBufferData(GL_ARRAY_BUFFER, sizeof(quad), quad, GL_STATIC_DRAW);
+                glGenVertexArrays(1, &m_vao);
+                glBindVertexArray(m_vao);
+                glEnableVertexAttribArray(0);
+                glVertexAttribPointer(0, 2, GL_FLOAT, GL_FALSE, sizeof(Vertex), nullptr);
+                glBindVertexArray(0);
+                ASSERT_EQ(FirstGLError(), GLenum(GL_NO_ERROR)) << "the scene setup left a GL error behind";
+            }
+
+            void TearDown() override {
+                if (!Ready() || IsSkipped()) return;
+                glUseProgram(0);
+                glBindVertexArray(0);
+                if (m_vao != 0) glDeleteVertexArrays(1, &m_vao);
+                if (m_quadBuffer != 0) glDeleteBuffers(1, &m_quadBuffer);
+                if (m_fetchProgram != 0) glDeleteProgram(m_fetchProgram);
+            }
+
+            // Direct State Access is how every setup step below touches a texture, and it is the
+            // whole reason the cases can claim "this texture never had a sampler view": the classic
+            // entry points (glTexImage2D, glTexParameteri) all require the texture to be BOUND to a
+            // unit first, and a bind is exactly what puts it on SyncNeccessaryTextures' unit list.
+            // A case that used them would sync the parameters through the path it is trying to
+            // exclude and would be green for the wrong reason, on every tree, forever.
+            bool DirectStateAccessIsAvailable() {
+                GLuint probe = 0;
+                glCreateTextures(GL_TEXTURE_2D, 1, &probe);
+                const bool ok = FirstGLError() == GLenum(GL_NO_ERROR) && probe != 0;
+                if (probe != 0) glDeleteTextures(1, &probe);
+                return ok;
+            }
+
+            void SkipWithoutDirectStateAccess() {
+                if (!DirectStateAccessIsAvailable()) {
+                    GTEST_SKIP() << "glCreateTextures is not usable here, and every case in this file "
+                                    "needs the DSA entry points: the classic ones bind the texture to "
+                                    "a unit, which is the reachability path these cases exist to "
+                                    "exclude. A case that fell back to them would be green for the "
+                                    "wrong reason rather than measuring anything.";
+                }
+            }
+
+            // A 4x4 RGBA8 texture, one solid colour, created and filled WITHOUT EVER BINDING IT.
+            GLuint MakeSolidTextureWithoutBinding(std::uint8_t r, std::uint8_t g, std::uint8_t b) {
+                std::vector<std::uint8_t> texels(kTextureSize * kTextureSize * 4);
+                for (std::size_t i = 0; i < texels.size(); i += 4) {
+                    texels[i] = r;
+                    texels[i + 1] = g;
+                    texels[i + 2] = b;
+                    texels[i + 3] = 255;
+                }
+                GLuint texture = 0;
+                glCreateTextures(GL_TEXTURE_2D, 1, &texture);
+                glTextureStorage2D(texture, 1, GL_RGBA8, kTextureSize, kTextureSize);
+                glTextureSubImage2D(texture, 0, 0, 0, kTextureSize, kTextureSize, GL_RGBA,
+                                    GL_UNSIGNED_BYTE, texels.data());
+                glTextureParameteri(texture, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+                glTextureParameteri(texture, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+                return texture;
+            }
+
+            // THE OBSERVATION, shared by every case: bind the texture to a unit for the first time
+            // in its life and read one texel back through the default framebuffer.
+            Image SampleAndRead(GLuint program, GLuint texture) {
+                BindDefaultFramebuffer();
+                glViewport(0, 0, Gl().Width(), Gl().Height());
+                ClearTo(0.0f, 0.0f, 0.0f, 1.0f);
+                glUseProgram(program);
+                glUniform1i(glGetUniformLocation(program, "uTex"), 0);
+                glActiveTexture(GL_TEXTURE0);
+                glBindTexture(GL_TEXTURE_2D, texture);
+                glBindVertexArray(m_vao);
+                glDrawArrays(GL_TRIANGLES, 0, 6);
+                const Image image = ReadPixels(Gl().Width(), Gl().Height());
+                Gl().EndFrame();
+                glBindTexture(GL_TEXTURE_2D, 0);
+                return image;
+            }
+
+            ::testing::AssertionResult WholeViewportIs(const Image& image, const char* expected,
+                                                       const std::string& when) {
+                return RegionIsMostly(image, kInset, image.Width() - kInset, kInset,
+                                      image.Height() - kInset, expected, 0.0, when);
+            }
+
+            // R -> ZERO and G -> ONE, so a RED texel samples as GREEN if and only if the swizzle
+            // reached the driver, and as RED if it did not. Two colours the harness can name, from
+            // one parameter change, with no third outcome that could be mistaken for either.
+            void SwizzleRedIntoGreen(GLuint texture) {
+                glTextureParameteri(texture, GL_TEXTURE_SWIZZLE_R, GL_ZERO);
+                glTextureParameteri(texture, GL_TEXTURE_SWIZZLE_G, GL_ONE);
+                glTextureParameteri(texture, GL_TEXTURE_SWIZZLE_B, GL_ZERO);
+            }
+
+            // Which of the two parameters a case moved, and therefore which one the white-box
+            // reading has to find on both sides of the seam. Two, because they are the two the
+            // four cases use and because a peek that reported "some parameter" would be green for
+            // a backend that applied the wrong one.
+            enum class MovedParameter { Swizzle, DepthStencilMode };
+
+            // ------------------------------------------------------------------------------
+            // G9's WHITE-BOX READING (ID-19). Called by every case at the point where its
+            // texture is reachable only its own way and BEFORE the observing sample - which is
+            // the whole of the design, because the sample repairs what it observes.
+            //
+            // `expectedSwizzle` is the four GL enums the case set (or left at their defaults);
+            // `expectedDepthStencilMode` is GL_DEPTH_COMPONENT or GL_STENCIL_INDEX. Both are
+            // always passed and `moved` says which one is the case's subject, so a reader of a
+            // failure can see the untouched half beside the moved one.
+            void TakeTheWhiteBoxReadingBeforeAnySample(GLuint texture, GLenum target,
+                                                       MovedParameter moved,
+                                                       const GLint expectedSwizzle[4],
+                                                       GLint expectedDepthStencilMode,
+                                                       const char* whatMadeItReachable) {
+                const char* const movedName =
+                    moved == MovedParameter::Swizzle ? "GL_TEXTURE_SWIZZLE_*"
+                                                     : "GL_DEPTH_STENCIL_TEXTURE_MODE";
+
+                PipeTextureParamsRecordPeek record{};
+                if (!PeekPipeTextureParamsRecord(static_cast<unsigned>(texture), &record)) {
+                    DeclineTheWhiteBoxReading(
+                        "no set_texture_params record for this texture in the applier. Either "
+                        "there is no applier here (a PULL build: MGPipeApplierState is "
+                        "#if MOBILEGL_PIPE_PUSH), or this lane's MOBILEGL_PIPE_PUSH leaves "
+                        "kMGPipeSubsystemTextureResources (bit 10) clear, or no backend "
+                        "registered MGPipeResourceOps so the client never emitted (c0f). The "
+                        "end-to-end half of this case below is unaffected and still decides it.");
+                    return;
+                }
+
+                // From here the reading WAS taken, so everything is a hard assertion: a record
+                // that exists and does not carry the parameter is exactly the finding.
+                EXPECT_NE(record.ParamsSerial, 0u)
+                    << "the applier holds a resource record for texture " << texture
+                    << " at handle {" << record.Slot << ", " << record.Gen
+                    << "} but its ParamsSerial is 0, i.e. NO set_texture_params has ever been "
+                       "applied to it - and this case moved " << movedName << " while the texture "
+                       "was " << whatMadeItReachable
+                    << ". A parameter change on a texture with no sampler view has to produce a "
+                       "record addressed BY RESOURCE (D10, D-E1); a zero here means the client "
+                       "never emitted one, which is the coupling P4a exists to remove reappearing "
+                       "on the emitter's side of the seam.";
+
+                if (moved == MovedParameter::Swizzle) {
+                    for (int channel = 0; channel < 4; ++channel) {
+                        EXPECT_EQ(record.Swizzle[channel], static_cast<int>(expectedSwizzle[channel]))
+                            << "the applier's set_texture_params record for texture " << texture
+                            << " carries the wrong swizzle in channel " << channel
+                            << " (record 0x" << std::hex << record.Swizzle[channel] << ", expected 0x"
+                            << expectedSwizzle[channel] << std::dec
+                            << "). The record is what Espryt reads, so a wrong value here is a "
+                               "wrong value everywhere downstream of it.";
+                    }
+                } else {
+                    EXPECT_EQ(record.DepthStencilMode, static_cast<int>(expectedDepthStencilMode))
+                        << "the applier's set_texture_params record for texture " << texture
+                        << " carries GL_DEPTH_STENCIL_TEXTURE_MODE 0x" << std::hex
+                        << record.DepthStencilMode << ", expected 0x" << expectedDepthStencilMode
+                        << std::dec << ".";
+                }
+
+                // (c) - and it is checked BEFORE (b) is read, because (b) reads the driver and a
+                // reader of a failure needs to know the view question was answered on the state
+                // this case built rather than on anything the peek did.
+                bool hasSamplerView = true;
+                if (!PeekEsprytHasSamplerViewForTexture(static_cast<unsigned>(texture),
+                                                        &hasSamplerView)) {
+                    DeclineTheWhiteBoxReading(
+                        "Espryt holds no twin for this texture, so neither the sampler-view "
+                        "question nor the applied-value one can be asked here. On a backend other "
+                        "than DirectGLES that is the designed state (P4a touches no DirectVulkan "
+                        "source but MagmaPipeArms.h, D-Q).");
+                    return;
+                }
+                EXPECT_FALSE(hasSamplerView)
+                    << "Espryt already holds a SAMPLER VIEW for texture " << texture
+                    << ", which was " << whatMadeItReachable
+                    << " and has never been bound to a sampler unit in this case. The whole claim "
+                       "of D10 is that a texture reached this way has no view, so if one exists "
+                       "the reading below cannot separate 'applied by resource' from 'applied "
+                       "through the view' and this case has stopped measuring G9.";
+
+                EsprytAppliedTextureParamsPeek applied{};
+                if (!PeekEsprytAppliedTextureParams(static_cast<unsigned>(texture),
+                                                    static_cast<unsigned>(target), &applied)) {
+                    DeclineTheWhiteBoxReading(
+                        "Espryt's applied value could not be read back from the driver (no twin, "
+                        "no ES name yet, or a target this peek has no binding query for).");
+                    return;
+                }
+
+                std::cout << "[ TextureParamsWithoutASamplerView ] white-box: texture " << texture
+                          << " -> applier handle {" << record.Slot << ", " << record.Gen
+                          << "} paramsSerial " << record.ParamsSerial << ", Espryt ES name "
+                          << applied.BackendTextureId << ", sampler view: none, " << movedName
+                          << " applied before any sample" << std::endl;
+
+                if (moved == MovedParameter::Swizzle) {
+                    for (int channel = 0; channel < 4; ++channel) {
+                        EXPECT_EQ(applied.Swizzle[channel], static_cast<int>(expectedSwizzle[channel]))
+                            << "ESPRYT HAS NOT APPLIED THE SWIZZLE YET. Channel " << channel
+                            << " of the driver texture (ES name " << applied.BackendTextureId
+                            << ") reads 0x" << std::hex << applied.Swizzle[channel] << ", the "
+                            << "application set 0x" << expectedSwizzle[channel] << std::dec
+                            << ", and the applier's record already carries the right value - so "
+                               "the record reached the server and the server has not pushed it. "
+                               "The texture was " << whatMadeItReachable
+                            << " and has NO sampler view (asserted above), which makes this "
+                               "exactly the deferred-to-first-view shape G9 exists to catch: the "
+                               "sample at the end of this case would repair it, and the "
+                               "end-to-end assertion below would then pass on a driver that was "
+                               "told late. That is the half no public-GL case can see.";
+                    }
+                } else {
+                    if (!applied.DepthStencilModeIsReadable) {
+                        DeclineTheWhiteBoxReading(
+                            "this driver would not answer glGetTexParameteriv("
+                            "GL_DEPTH_STENCIL_TEXTURE_MODE), so the applied aspect mode cannot be "
+                            "read back. The record half above was still asserted.");
+                        return;
+                    }
+                    EXPECT_EQ(applied.DepthStencilMode, static_cast<int>(expectedDepthStencilMode))
+                        << "ESPRYT HAS NOT APPLIED THE DEPTH/STENCIL ASPECT MODE YET. The driver "
+                           "texture (ES name " << applied.BackendTextureId << ") reads 0x"
+                        << std::hex << applied.DepthStencilMode << ", the application set 0x"
+                        << expectedDepthStencilMode << std::dec
+                        << ", and the applier's record already carries the right value. The "
+                           "texture was " << whatMadeItReachable
+                        << " and has no sampler view, so this is D-E3's gap measured directly "
+                           "rather than through a sample that would repair it: a driver left at "
+                           "GL_DEPTH_COMPONENT samples the DEPTH bits where the application asked "
+                           "for stencil.";
+                }
+            }
+
+            // Printed, recorded and named, never silent - a lane that stopped taking the reading
+            // must be visible in the log. See this file's header for why it is not a GTEST_SKIP.
+            void DeclineTheWhiteBoxReading(const std::string& why) {
+                std::cout << "[ TextureParamsWithoutASamplerView ] white-box reading DECLINED: "
+                          << why << std::endl;
+                RecordProperty("g9_white_box", "declined");
+                RecordProperty("g9_white_box_reason", why.c_str());
+            }
+
+            GLuint m_fetchProgram = 0;
+            GLuint m_vao = 0;
+            GLuint m_quadBuffer = 0;
+        };
+
+        // The swizzle SwizzleRedIntoGreen leaves behind, as GL enums: R -> ZERO, G -> ONE,
+        // B -> ZERO and A untouched at its GL default. Written once here because both the
+        // applier record and the driver read-back are compared against it.
+        constexpr GLint kRedIntoGreenSwizzle[4] = {GL_ZERO, GL_ONE, GL_ZERO, GL_ALPHA};
+        // A texture whose aspect mode was never touched, i.e. the GL initial value - which is
+        // also what a zeroed MGPTextureParams::DepthStencilMode decodes to (MGPipeTypes.h).
+        constexpr GLint kUntouchedDepthStencilMode = GL_DEPTH_COMPONENT;
+        // ...and the identity swizzle, for the case whose subject is the aspect mode: the moved
+        // half is asserted, and the untouched half is carried so a failure prints both.
+        constexpr GLint kUntouchedSwizzle[4] = {GL_RED, GL_GREEN, GL_BLUE, GL_ALPHA};
+
+        // ------------------------------------------------------------------------------------
+        // 1. DRAW ATTACHMENT ONLY. Green today (SyncNeccessaryTextures' FBO list walks the draw
+        //    slot and calls SyncTextureObjectToBackend, which syncs parameters) and green after.
+        //    It is the regression net for the half of D-E3 that already works: P4a moves the
+        //    parameter sync from the sync list onto the record, and this case is what says the
+        //    move did not lose the case that used to be covered.
+        // ------------------------------------------------------------------------------------
+        TEST_F(TextureParamsWithoutASamplerViewScenario, AnAttachmentOnlyTexturesSwizzleReachesTheDriver) {
+            if (!Ready()) return;
+            SkipWithoutDirectStateAccess();
+            if (IsSkipped()) return;
+
+            const GLuint texture = MakeSolidTextureWithoutBinding(255, 0, 0);
+            GLuint fbo = 0;
+            glGenFramebuffers(1, &fbo);
+            glBindFramebuffer(GL_DRAW_FRAMEBUFFER, fbo);
+            glFramebufferTexture2D(GL_DRAW_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, texture, 0);
+            ASSERT_EQ(glCheckFramebufferStatus(GL_DRAW_FRAMEBUFFER), GLenum(GL_FRAMEBUFFER_COMPLETE));
+
+            // The parameter moves while the texture is reachable ONLY as a draw attachment...
+            SwizzleRedIntoGreen(texture);
+            // ...and a frame runs with it bound that way, so whatever the draw path syncs, syncs.
+            glViewport(0, 0, kTextureSize, kTextureSize);
+            ClearTo(1.0f, 0.0f, 0.0f, 1.0f);
+            BindDefaultFramebuffer();
+            Gl().EndFrame();
+            ASSERT_EQ(FirstGLError(), GLenum(GL_NO_ERROR)) << "the draw-attachment frame left a GL error";
+
+            glBindFramebuffer(GL_FRAMEBUFFER, 0);
+            glDeleteFramebuffers(1, &fbo);
+
+            // G9's white-box reading, taken here: the texture has been a draw attachment and
+            // nothing else, and the sample below has not happened yet.
+            TakeTheWhiteBoxReadingBeforeAnySample(texture, GL_TEXTURE_2D, MovedParameter::Swizzle,
+                                                  kRedIntoGreenSwizzle, kUntouchedDepthStencilMode,
+                                                  "an attachment of the DRAW framebuffer and "
+                                                  "nothing else");
+
+            const Image image = SampleAndRead(m_fetchProgram, texture);
+            EXPECT_TRUE(WholeViewportIs(image, "green",
+                                        "a texture that was only ever a DRAW attachment, sampled "
+                                        "after its swizzle moved"))
+                << "the swizzle set while this texture was reachable only as a draw-framebuffer "
+                   "attachment did not reach the driver: a red texel with R->ZERO, G->ONE must "
+                   "sample as green.";
+
+            GLuint cleanup = texture;
+            glDeleteTextures(1, &cleanup);
+        }
+
+        // ------------------------------------------------------------------------------------
+        // 2. READ ATTACHMENT ONLY - THE MANDATORY RED (ROADMAP.md:20, D-E3, G9).
+        //
+        //    The parameter is GL_DEPTH_STENCIL_TEXTURE_MODE and the texture is a packed
+        //    depth/stencil one, because that is the parameter whose absence is not a mis-filtered
+        //    picture but the WRONG ASPECT: a driver left at the GL default samples the depth bits
+        //    where the application asked for stencil, and the value that comes back is not the
+        //    stencil that was written. RecreateBackendTexture's own comment says exactly this -
+        //    "the mode makes it visible because falling back to the default silently samples the
+        //    wrong aspect rather than merely mis-filtering" (Managers.cpp:4826-4833).
+        //
+        //    The framebuffer is bound to GL_READ_FRAMEBUFFER and the DRAW target is left on the
+        //    default framebuffer for the whole window, which is the ONE thing that separates this
+        //    case from the one above.
+        // ------------------------------------------------------------------------------------
+        TEST_F(TextureParamsWithoutASamplerViewScenario,
+               AReadAttachmentOnlyTexturesDepthStencilModeReachesTheDriver) {
+            if (!Ready()) return;
+            SkipWithoutDirectStateAccess();
+            if (IsSkipped()) return;
+
+            std::string error;
+            const GLuint stencilProgram = CompileProgram(kQuadVS, kStencilFetchFS, &error);
+            ASSERT_NE(stencilProgram, 0u) << error;
+
+            GLuint texture = 0;
+            glCreateTextures(GL_TEXTURE_2D, 1, &texture);
+            glTextureStorage2D(texture, 1, GL_DEPTH24_STENCIL8, kTextureSize, kTextureSize);
+            glTextureParameteri(texture, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+            glTextureParameteri(texture, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+            if (FirstGLError() != GLenum(GL_NO_ERROR)) {
+                glDeleteTextures(1, &texture);
+                glDeleteProgram(stencilProgram);
+                GTEST_SKIP() << "this driver would not create an immutable DEPTH24_STENCIL8 texture, "
+                                "so there is no packed depth/stencil aspect here to sample and the "
+                                "case cannot answer";
+            }
+
+            // Write a stencil value through the texture AS A DRAW ATTACHMENT once, so that there is
+            // something in the stencil aspect to read. This is setup, not the window: the window
+            // below never makes it a draw attachment again.
+            GLuint fbo = 0;
+            glGenFramebuffers(1, &fbo);
+            glBindFramebuffer(GL_FRAMEBUFFER, fbo);
+            glFramebufferTexture2D(GL_FRAMEBUFFER, GL_DEPTH_STENCIL_ATTACHMENT, GL_TEXTURE_2D, texture, 0);
+            glDrawBuffer(GL_NONE);
+            glReadBuffer(GL_NONE);
+            if (glCheckFramebufferStatus(GL_FRAMEBUFFER) != GLenum(GL_FRAMEBUFFER_COMPLETE)) {
+                BindDefaultFramebuffer();
+                glDeleteFramebuffers(1, &fbo);
+                glDeleteTextures(1, &texture);
+                glDeleteProgram(stencilProgram);
+                GTEST_SKIP() << "a depth-stencil-only framebuffer is incomplete on this driver, so "
+                                "the stencil aspect cannot be written and the case cannot answer";
+            }
+            constexpr GLint kStencil = 42;
+            glViewport(0, 0, kTextureSize, kTextureSize);
+            glStencilMask(0xFFu);
+            glClearBufferfi(GL_DEPTH_STENCIL, 0, 0.5f, kStencil);
+            BindDefaultFramebuffer();
+            Gl().EndFrame();
+            ASSERT_EQ(FirstGLError(), GLenum(GL_NO_ERROR)) << "clearing the stencil aspect left a GL error";
+
+            // ---- the window: the texture is reachable ONLY as a READ attachment ----
+            //
+            // The DRAW binding is the default framebuffer throughout, so SyncNeccessaryTextures'
+            // attachment list - which walks the DRAW slot only - never sees this texture, and
+            // SyncCurrentFBO's read path reaches it through SyncAttachmentObject, which syncs
+            // storage and not parameters. That is the gap.
+            glBindFramebuffer(GL_READ_FRAMEBUFFER, fbo);
+            glBindFramebuffer(GL_DRAW_FRAMEBUFFER, 0);
+            glTextureParameteri(texture, GL_DEPTH_STENCIL_TEXTURE_MODE, GL_STENCIL_INDEX);
+            // A frame with the read binding live, and it has to contain a REAL DRAW: SyncCurrentFBO
+            // and the whole sync-list walk run at the validate point, so a frame that only cleared
+            // and swapped would never reach the read-side path this case is about.
+            glViewport(0, 0, Gl().Width(), Gl().Height());
+            ClearTo(0.0f, 0.0f, 0.0f, 1.0f);
+            glUseProgram(m_fetchProgram);
+            glUniform1i(glGetUniformLocation(m_fetchProgram, "uTex"), 0);
+            glActiveTexture(GL_TEXTURE0);
+            glBindTexture(GL_TEXTURE_2D, 0);
+            glBindVertexArray(m_vao);
+            glDrawArrays(GL_TRIANGLES, 0, 6);
+            Gl().EndFrame();
+            glBindFramebuffer(GL_READ_FRAMEBUFFER, 0);
+            ASSERT_EQ(FirstGLError(), GLenum(GL_NO_ERROR)) << "the read-attachment frame left a GL error";
+
+            // G9's white-box reading, and this is the case it matters most for: the aspect
+            // mode was set while the texture was reachable ONLY as a read attachment, and the
+            // observation below is a sample that would repair an unsynced parameter on its way
+            // to reporting it.
+            TakeTheWhiteBoxReadingBeforeAnySample(texture, GL_TEXTURE_2D,
+                                                  MovedParameter::DepthStencilMode,
+                                                  kUntouchedSwizzle, GL_STENCIL_INDEX,
+                                                  "an attachment of the READ framebuffer and "
+                                                  "nothing else");
+
+            // ---- the observation ----
+            BindDefaultFramebuffer();
+            glViewport(0, 0, Gl().Width(), Gl().Height());
+            ClearTo(0.0f, 0.0f, 0.0f, 1.0f);
+            glUseProgram(stencilProgram);
+            glUniform1i(glGetUniformLocation(stencilProgram, "uTex"), 0);
+            glUniform1ui(glGetUniformLocation(stencilProgram, "uExpected"),
+                         static_cast<GLuint>(kStencil));
+            glActiveTexture(GL_TEXTURE0);
+            glBindTexture(GL_TEXTURE_2D, texture);
+            glBindVertexArray(m_vao);
+            glDrawArrays(GL_TRIANGLES, 0, 6);
+            const Image image = ReadPixels(Gl().Width(), Gl().Height());
+            Gl().EndFrame();
+            glBindTexture(GL_TEXTURE_2D, 0);
+
+            const GLenum sampleError = FirstGLError();
+            std::cout << "[ TextureParamsWithoutASamplerView ] read-attachment-only "
+                         "GL_DEPTH_STENCIL_TEXTURE_MODE=GL_STENCIL_INDEX, expecting stencil "
+                      << kStencil << "; sample GL error 0x" << std::hex << sampleError << std::dec
+                      << std::endl;
+
+            EXPECT_TRUE(WholeViewportIs(image, "green",
+                                        "a texture that was only ever a READ attachment, sampled "
+                                        "through its stencil aspect"))
+                << "GL_DEPTH_STENCIL_TEXTURE_MODE = GL_STENCIL_INDEX was set while this texture was "
+                   "reachable ONLY as an attachment of the READ framebuffer, and the sample did not "
+                   "come back as the stencil value that was cleared into it. The parameter did not "
+                   "reach the driver, and - because the sample itself would have repaired an "
+                   "unsynced parameter (see this file's header: the unit sync list calls "
+                   "SyncTextureParamsToBackend whenever the params version moved) - a red here means "
+                   "something stronger than the D-E3 gap: a reachability path that does not sync "
+                   "parameters AT ALL, i.e. the sampler-view coupling ARCHITECTURE.md:100 (D10) "
+                   "exists to remove. Read the case's own stdout line for the GL error the sample "
+                   "raised before assuming an aspect-mode bug.";
+
+            BindDefaultFramebuffer();
+            glDeleteFramebuffers(1, &fbo);
+            glDeleteTextures(1, &texture);
+            glDeleteProgram(stencilProgram);
+        }
+
+        // ------------------------------------------------------------------------------------
+        // 3. IMAGE UNIT ONLY, across a storage RE-MINT. Green today and green after, and the
+        //    reason it is green is the thing P4a must not lose: glBindImageTexture drives
+        //    RequireImageBindableStorage, which re-mints the storage in a possibly WIDENED carrier
+        //    and sets m_forceTextureParamsResync (Managers.cpp:4787) precisely because the
+        //    frontend's parameter version does not move across that transition. A parameter sync
+        //    gated only on the frontend version would leave the driver at its defaults and sample
+        //    the carrier's surplus channels raw.
+        // ------------------------------------------------------------------------------------
+        TEST_F(TextureParamsWithoutASamplerViewScenario,
+               AnImageUnitOnlyTexturesSwizzleSurvivesARequireImageBindableStorageRemint) {
+            if (!Ready()) return;
+            SkipWithoutDirectStateAccess();
+            if (IsSkipped()) return;
+
+            const GLuint texture = MakeSolidTextureWithoutBinding(255, 0, 0);
+
+            // The parameter moves while the texture is reachable only as an image-unit binding...
+            SwizzleRedIntoGreen(texture);
+            glBindImageTexture(0, texture, 0, GL_FALSE, 0, GL_READ_ONLY, GL_RGBA8);
+            const GLenum bindError = FirstGLError();
+            if (bindError != GLenum(GL_NO_ERROR)) {
+                glBindImageTexture(0, 0, 0, GL_FALSE, 0, GL_READ_ONLY, GL_RGBA8);
+                GLuint cleanup = texture;
+                glDeleteTextures(1, &cleanup);
+                GTEST_SKIP() << "glBindImageTexture is not usable here (GL error 0x" << std::hex
+                             << bindError << std::dec
+                             << "), so the RequireImageBindableStorage transition this case is about "
+                                "cannot be reached";
+            }
+            // ...and a frame runs with the image binding live, which is what drives the re-mint.
+            glViewport(0, 0, Gl().Width(), Gl().Height());
+            ClearTo(0.0f, 0.0f, 0.0f, 1.0f);
+            Gl().EndFrame();
+            glBindImageTexture(0, 0, 0, GL_FALSE, 0, GL_READ_ONLY, GL_RGBA8);
+
+            // G9's white-box reading. RGBA8 is a core image format, so no widening carrier is
+            // minted and the driver's swizzle is the application's own - the composition
+            // RecreateBackendTexture applies for a NON-core format would show up here as a
+            // legitimate difference and this case deliberately does not use one.
+            TakeTheWhiteBoxReadingBeforeAnySample(texture, GL_TEXTURE_2D, MovedParameter::Swizzle,
+                                                  kRedIntoGreenSwizzle, kUntouchedDepthStencilMode,
+                                                  "an image-unit binding and nothing else, across "
+                                                  "a RequireImageBindableStorage re-mint");
+
+            const Image image = SampleAndRead(m_fetchProgram, texture);
+            EXPECT_TRUE(WholeViewportIs(image, "green",
+                                        "a texture that was only ever an image-unit binding, sampled "
+                                        "after its swizzle moved and its storage was re-minted"))
+                << "the swizzle did not survive the RequireImageBindableStorage re-mint. The re-mint "
+                   "creates a new driver texture at the ES defaults without moving the frontend's "
+                   "parameter version, so the forced resync (Managers.cpp:4787) is the only thing "
+                   "that puts the application's parameters back.";
+
+            GLuint cleanup = texture;
+            glDeleteTextures(1, &cleanup);
+        }
+
+        // ------------------------------------------------------------------------------------
+        // 4. glCopyImageSubData ENDPOINT ONLY. Green today (MakeGLESCopyImageEndpoint calls
+        //    SyncTextureObjectToBackend, DirectGLES.cpp:7588) and green after. The endpoint is the
+        //    DESTINATION, so the case also proves the copy itself still lands: a swizzled read of
+        //    the copied texel is only meaningful if the texel arrived.
+        // ------------------------------------------------------------------------------------
+        TEST_F(TextureParamsWithoutASamplerViewScenario,
+               ACopyImageEndpointOnlyTexturesParamsReachTheDriver) {
+            if (!Ready()) return;
+            SkipWithoutDirectStateAccess();
+            if (IsSkipped()) return;
+
+            const GLuint source = MakeSolidTextureWithoutBinding(255, 0, 0);
+            const GLuint destination = MakeSolidTextureWithoutBinding(0, 0, 255);
+
+            // The parameter moves while the destination is reachable only as a copy endpoint...
+            SwizzleRedIntoGreen(destination);
+            glCopyImageSubData(source, GL_TEXTURE_2D, 0, 0, 0, 0, destination, GL_TEXTURE_2D, 0, 0, 0,
+                               0, kTextureSize, kTextureSize, 1);
+            const GLenum copyError = FirstGLError();
+            if (copyError != GLenum(GL_NO_ERROR)) {
+                GLuint cleanup[2] = {source, destination};
+                glDeleteTextures(2, cleanup);
+                GTEST_SKIP() << "glCopyImageSubData is not usable here (GL error 0x" << std::hex
+                             << copyError << std::dec << "), so there is no copy endpoint to be";
+            }
+            Gl().EndFrame();
+
+            // G9's white-box reading, on the DESTINATION - the endpoint whose parameters moved.
+            TakeTheWhiteBoxReadingBeforeAnySample(destination, GL_TEXTURE_2D,
+                                                  MovedParameter::Swizzle, kRedIntoGreenSwizzle,
+                                                  kUntouchedDepthStencilMode,
+                                                  "a glCopyImageSubData destination and nothing "
+                                                  "else");
+
+            // ...and the destination now holds the source's RED texel, which the swizzle must turn
+            // into GREEN when it is finally sampled.
+            const Image image = SampleAndRead(m_fetchProgram, destination);
+            EXPECT_TRUE(WholeViewportIs(image, "green",
+                                        "a texture that was only ever a glCopyImageSubData endpoint, "
+                                        "sampled after its swizzle moved"))
+                << "the three readings are distinct and each names its own cause: GREEN is the pass "
+                   "(the swizzle reached the driver); RED means the copy landed and the swizzle did "
+                   "not; BLUE means neither happened, i.e. the destination is still its own original "
+                   "texel and glCopyImageSubData wrote nothing. The swizzle is what turns any texel "
+                   "into (0,1,0), so the colour separates the two failures rather than merging them.";
+
+            GLuint cleanup[2] = {source, destination};
+            glDeleteTextures(2, cleanup);
+        }
+
+    } // namespace
+} // namespace MGITest

MobileGL/MG_IntegrationTest/Scenarios/TextureUploadShapeScenario.cpp

@@ -0,0 +1,396 @@
+// MobileGL - MobileGL/MG_IntegrationTest/Scenarios/TextureUploadShapeScenario.cpp
+// Copyright (c) 2026 MobileGL-Dev
+// Licensed under the GNU Lesser General Public License v3.0:
+//   https://www.gnu.org/licenses/gpl-3.0.txt
+//   https://www.gnu.org/licenses/lgpl-3.0.txt
+// SPDX-License-Identifier: LGPL-3.0-only
+// End of Source File Header
+//
+// Scenario - THE TEXTURE UPLOAD SHAPE, RECORDED (BRIEF-P4A.md D-D4). NOT A GATE IN P4a.
+//
+// WHAT IT IS FOR. SSIM is completely blind to the difference between "one union box" and "N
+// separate rects", and that difference is the Mali upload cliff: Mali prices an upload by the
+// number of JOBS, and ~100 one-rect sprite jobs against one union box measured +6 ms/frame
+// (ARCHITECTURE.md:249-251). Every P4a gate can be green while the emission shape has silently
+// inverted, so the shape needs a number - and there are TWO numbers, deliberately:
+//
+//   tex[emit= box= rect= jobs=]   the SERVER's count, Espryt's own, which has existed since P2
+//   emit[ctu=]                    the CLIENT's count of the same records (CallClass::
+//                                 ClientTextureUploadEmissions, minted by the P4a contract commit)
+//
+// The two agreeing is the whole reason both are printed (D-L). An emission-shape divergence between
+// the client that decides the rect model and the server that pays the GPU cost is then a difference
+// of two published numbers rather than something only a device can see.
+//
+// WHY IT IS RECORDED AND NOT GATED, and this is a scope decision rather than a hedge. ROADMAP.md:23
+// puts "dirty 归属反转（按存储属主键控的发射游标）" in the P3b/P4b cell: P4a lands the flat drain
+// list, and the per-storage-owner emission cursor with view/owner index remapping - which is what
+// actually decides the shape for a texture uploaded through a VIEW - is the next phase's. Gating a
+// shape the phase has not finished deciding would either pin today's shape as if it were the
+// answer, or fail on a change that is the point of the next phase. So P4a BUILDS the scenario (it
+// is meaningless without P4a's records) and runs it as a RECORDED comparison; P3b/P4b turns it into
+// a gate with the Mali frame-time delta published beside it (D-D4).
+//
+// WHAT IT THEREFORE ASSERTS, and it is not nothing:
+//
+//   1. the numbers could be READ AT ALL - the counters exist, the window covers the workload, and
+//      the workload really uploaded (a run that uploaded nothing would record four zeroes and look
+//      exactly like a healthy run whose emitter had been switched off);
+//   2. the internal ARITHMETIC of the server's own bracket holds: emit == box + rect, and
+//      jobs >= emit, because a box emission is one job and a rect-list emission is N;
+//   3. the client and the server agree on the RECORD COUNT when both are non-zero (ctu == emit).
+//      Not "when the client is non-zero": on the P4a contract tree the client emits nothing and
+//      that is a SKIP-shaped observation, not a divergence.
+//
+// Everything else - which shape each texture took, and whether that is the right shape - is
+// RECORDED with RecordProperty and printed, for MEASUREMENTS.md and for the P3b/P4b gate to be
+// written against.
+//
+// THE WORKLOAD is the shape the decision is about: one texture receiving MANY SMALL SCATTERED
+// SUB-REGIONS per frame (the sprite-atlas / chunk-renderer shape), and one receiving a single large
+// contiguous one. The first is where the box-versus-rect choice is made - MipmapStorage's 96-rect
+// cascade and the summedArea*4 >= unionArea*3 union-box fallback - and the second is the control
+// that must always be one box whatever the policy is.
+//
+// DIRECTGLES ONLY. The server-side counters are Espryt's (Managers.cpp:6360-6395); Magma's upload
+// path is P7 and contributes nothing to them, so a DirectVulkan lane would record a bracket of
+// zeroes and call it a shape.
+
+#include <cstdint>
+#include <cstdlib>
+#include <iostream>
+#include <string>
+#include <vector>
+
+#include "../Harness/HeadlessGL.h"
+#include "../Harness/PipeStatsWindow.h"
+#include "../Harness/ScenarioFixture.h"
+
+#ifdef GLAPI
+#undef GLAPI
+#endif
+#define GL_GLEXT_PROTOTYPES
+#include <GL/gl.h>
+#include <GL/glcorearb.h>
+#undef GL_GLEXT_PROTOTYPES
+
+namespace MGITest {
+    namespace {
+
+        // Set by the TextureUploadShape. ctest entry and by nothing else; a harness marker, never
+        // read by the library.
+        constexpr const char* kLaneMarker = "MGITEST_TEXTURE_UPLOAD_SHAPE_LANE";
+
+        constexpr int kInset = 2;
+        constexpr int kAtlasSize = 64;
+        // Enough scattered rects that the box-versus-rect policy has a real decision to make: the
+        // rect cascade caps at MipmapStorage::kMaxDirtyRects = 96, and the union-box fallback fires
+        // on summedArea*4 >= unionArea*3, so a handful of rects would take neither branch
+        // interestingly.
+        constexpr int kScatteredRects = 40;
+        constexpr int kRectSize = 2;
+        constexpr int kFrames = 3;
+
+        constexpr const char* kVS = R"(#version 330 core
+in vec2 aPos;
+out vec2 vUv;
+void main() {
+    vUv = aPos * 0.5 + 0.5;
+    gl_Position = vec4(aPos, 0.0, 1.0);
+}
+)";
+
+        constexpr const char* kFS = R"(#version 330 core
+in vec2 vUv;
+uniform sampler2D uTex;
+out vec4 oColor;
+void main() { oColor = texture(uTex, vUv); }
+)";
+
+        struct Vertex {
+            float x, y;
+        };
+
+        bool BuildMarkerIsSet(const char* name) {
+            const char* value = std::getenv(name);
+            return value != nullptr && value[0] == '1' && value[1] == '\0';
+        }
+
+        class TextureUploadShapeScenario : public ScenarioTest {
+        protected:
+            void SetUp() override {
+                ScenarioTest::SetUp();
+                if (!Ready()) return;
+                std::string error;
+                m_program = CompileProgram(kVS, kFS, &error);
+                ASSERT_NE(m_program, 0u) << error;
+
+                static const Vertex quad[6] = {{-1.0f, -1.0f}, {1.0f, -1.0f}, {1.0f, 1.0f},
+                                               {-1.0f, -1.0f}, {1.0f, 1.0f},  {-1.0f, 1.0f}};
+                glGenBuffers(1, &m_quadBuffer);
+                glBindBuffer(GL_ARRAY_BUFFER, m_quadBuffer);
+                glBufferData(GL_ARRAY_BUFFER, sizeof(quad), quad, GL_STATIC_DRAW);
+                glGenVertexArrays(1, &m_vao);
+                glBindVertexArray(m_vao);
+                glEnableVertexAttribArray(0);
+                glVertexAttribPointer(0, 2, GL_FLOAT, GL_FALSE, sizeof(Vertex), nullptr);
+                glBindVertexArray(0);
+            }
+
+            void TearDown() override {
+                if (!Ready()) return;
+                glUseProgram(0);
+                glBindVertexArray(0);
+                glBindTexture(GL_TEXTURE_2D, 0);
+                glBindBuffer(GL_ARRAY_BUFFER, 0);
+                if (m_scattered != 0) glDeleteTextures(1, &m_scattered);
+                if (m_contiguous != 0) glDeleteTextures(1, &m_contiguous);
+                if (m_vao != 0) glDeleteVertexArrays(1, &m_vao);
+                if (m_quadBuffer != 0) glDeleteBuffers(1, &m_quadBuffer);
+                if (m_program != 0) glDeleteProgram(m_program);
+            }
+
+            void SkipUnlessTheLaneIsAssertableHere() {
+                if (std::getenv(kLaneMarker) == nullptr) {
+                    GTEST_SKIP() << "runs only in its own lane: the TextureUploadShape. ctest entry "
+                                    "sets " << kLaneMarker
+                                 << " together with MOBILEGL_PIPE_STATS=1, "
+                                    "MOBILEGL_PIPE_STATS_PERIOD=1 and a private "
+                                    "MOBILEGL_LOG_FILE_PATH. None of that is configured in the "
+                                    "ambient entries, and the ambient log is shared, so a read here "
+                                    "would race.";
+                    return;
+                }
+                if (Gl().BackendName() != "DirectGLES") {
+                    GTEST_SKIP() << "DirectGLES only: the upload-shape counters are Espryt's "
+                                    "(Managers.cpp:6360-6395) and " << Gl().BackendName()
+                                 << " contributes nothing to them, so this lane would record a "
+                                    "bracket of zeroes and call it a shape.";
+                    return;
+                }
+                if (!BuildMarkerIsSet("MGITEST_PIPE_PUSH_BUILD")) {
+                    GTEST_SKIP() << "this library was built without MOBILEGL_PIPE_PUSH: the client's "
+                                    "half of the comparison (CallClass::ClientTextureUploadEmissions, "
+                                    "the ctu= field) does not exist there, and a one-sided reading is "
+                                    "not the comparison this scenario is for. The entry is registered "
+                                    "in every build so that `ctest -L integration-gpu` names the same "
+                                    "tests in the pull build and the push build (gate G2).";
+                    return;
+                }
+                if (PipeStatsWindow::LibraryLogPath().empty()) {
+                    GTEST_SKIP() << "the lane configured no MOBILEGL_LOG_FILE_PATH, and the library's "
+                                    "summary line is the only channel this module has for reading "
+                                    "PipeStats";
+                    return;
+                }
+            }
+
+            GLuint MakeAtlas(std::uint8_t r, std::uint8_t g, std::uint8_t b) {
+                std::vector<std::uint8_t> texels(static_cast<std::size_t>(kAtlasSize) * kAtlasSize * 4);
+                for (std::size_t i = 0; i < texels.size(); i += 4) {
+                    texels[i] = r;
+                    texels[i + 1] = g;
+                    texels[i + 2] = b;
+                    texels[i + 3] = 255;
+                }
+                GLuint texture = 0;
+                glGenTextures(1, &texture);
+                glBindTexture(GL_TEXTURE_2D, texture);
+                glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, kAtlasSize, kAtlasSize, 0, GL_RGBA,
+                             GL_UNSIGNED_BYTE, texels.data());
+                glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+                glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+                glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_BASE_LEVEL, 0);
+                glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAX_LEVEL, 0);
+                return texture;
+            }
+
+            Image DrawSampled(GLuint texture) {
+                BindDefaultFramebuffer();
+                glViewport(0, 0, Gl().Width(), Gl().Height());
+                glUseProgram(m_program);
+                glUniform1i(glGetUniformLocation(m_program, "uTex"), 0);
+                glActiveTexture(GL_TEXTURE0);
+                glBindTexture(GL_TEXTURE_2D, texture);
+                glBindVertexArray(m_vao);
+                glDrawArrays(GL_TRIANGLES, 0, 6);
+                return ReadPixels(Gl().Width(), Gl().Height());
+            }
+
+            GLuint m_program = 0;
+            GLuint m_vao = 0;
+            GLuint m_quadBuffer = 0;
+            GLuint m_scattered = 0;
+            GLuint m_contiguous = 0;
+        };
+
+        TEST_F(TextureUploadShapeScenario, TheEmittedUploadShapeIsRecordedAndTheTwoSidesAgree) {
+            if (!Ready()) return;
+            SkipUnlessTheLaneIsAssertableHere();
+            if (IsSkipped()) return;
+
+            m_scattered = MakeAtlas(0, 255, 0);
+            m_contiguous = MakeAtlas(0, 255, 0);
+            // The first draw of each texture uploads its whole level, which is not the shape this
+            // scenario is about; it happens in the SETUP window, before the one that is read.
+            DrawSampled(m_scattered);
+            DrawSampled(m_contiguous);
+            BindDefaultFramebuffer();
+            Gl().EndFrame();
+
+            // ---- the counted window ----
+            Image lastScattered;
+            Image lastContiguous;
+            for (int frame = 0; frame < kFrames; ++frame) {
+                // MANY SMALL SCATTERED RECTS: the shape whose box-versus-rect decision is the whole
+                // subject. They are spread over the atlas on a coarse stride so that their union
+                // box is most of the texture and their summed area is a small fraction of it -
+                // which is the input the summedArea*4 >= unionArea*3 fallback is written for.
+                glBindTexture(GL_TEXTURE_2D, m_scattered);
+                const std::uint8_t patch[kRectSize * kRectSize * 4] = {
+                    0, 255, 0, 255, 0, 255, 0, 255, 0, 255, 0, 255, 0, 255, 0, 255};
+                for (int rect = 0; rect < kScatteredRects; ++rect) {
+                    const int x = ((rect * 7) % (kAtlasSize / kRectSize)) * kRectSize;
+                    const int y = ((rect * 5) % (kAtlasSize / kRectSize)) * kRectSize;
+                    glTexSubImage2D(GL_TEXTURE_2D, 0, x, y, kRectSize, kRectSize, GL_RGBA,
+                                    GL_UNSIGNED_BYTE, patch);
+                }
+                lastScattered = DrawSampled(m_scattered);
+
+                // ONE LARGE CONTIGUOUS REGION: the control. Whatever the policy is, this is one
+                // box and one job, and a reading where it is not says the policy has stopped
+                // looking at the region at all.
+                glBindTexture(GL_TEXTURE_2D, m_contiguous);
+                std::vector<std::uint8_t> band(static_cast<std::size_t>(kAtlasSize) * 8 * 4);
+                for (std::size_t i = 0; i < band.size(); i += 4) {
+                    band[i] = 0;
+                    band[i + 1] = 255;
+                    band[i + 2] = 0;
+                    band[i + 3] = 255;
+                }
+                glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, kAtlasSize, 8, GL_RGBA, GL_UNSIGNED_BYTE,
+                                band.data());
+                lastContiguous = DrawSampled(m_contiguous);
+            }
+            ASSERT_EQ(FirstGLError(), GLenum(GL_NO_ERROR)) << "the upload workload left a GL error behind";
+            Gl().EndFrame(); // the swap that emits the window covering exactly the work above
+
+            const PipeStatsWindow::Window window = PipeStatsWindow::LastFromLaneLog();
+            ASSERT_TRUE(window.found)
+                << "no 'MGPipe stats:' line in " << PipeStatsWindow::LibraryLogPath()
+                << ", so the shape could not be read at all";
+            RecordProperty("stats_line", window.line.c_str());
+
+            const long long emissions = PipeStatsWindow::CounterOrAbsent(window, "emit");
+            const long long box = PipeStatsWindow::CounterOrAbsent(window, "box");
+            const long long rect = PipeStatsWindow::CounterOrAbsent(window, "rect");
+            const long long jobs = PipeStatsWindow::CounterOrAbsent(window, "jobs");
+            const long long clientEmissions = PipeStatsWindow::CounterOrAbsent(window, "ctu");
+            ASSERT_GE(emissions, 0) << "the summary line carries no tex[emit=]: " << window.line;
+            ASSERT_GE(box, 0) << "no box=: " << window.line;
+            ASSERT_GE(rect, 0) << "no rect=: " << window.line;
+            ASSERT_GE(jobs, 0) << "no jobs=: " << window.line;
+
+            // THE RECORD. This is the deliverable of this scenario in P4a: a number, in the ctest
+            // XML and in the log, for MEASUREMENTS.md and for the P3b/P4b gate to be written
+            // against. Printed as well as recorded, because a RecordProperty is invisible in a
+            // console run.
+            std::cout << "[ TextureUploadShape ] backend=" << Gl().BackendName() << " frames=" << kFrames
+                      << " scattered_rects_per_frame=" << kScatteredRects
+                      << " server[emit=" << emissions << " box=" << box << " rect=" << rect
+                      << " jobs=" << jobs << "] client[ctu=" << clientEmissions << "]" << std::endl;
+            RecordProperty("server_emissions", static_cast<int>(emissions));
+            RecordProperty("server_box_emissions", static_cast<int>(box));
+            RecordProperty("server_rect_emissions", static_cast<int>(rect));
+            RecordProperty("server_upload_jobs", static_cast<int>(jobs));
+            RecordProperty("client_emissions", static_cast<int>(clientEmissions));
+
+            // 1. the workload really uploaded. Without this the three assertions below are all
+            //    0 == 0 and a run whose emitter was switched off records the same "healthy" shape
+            //    as one that worked.
+            ASSERT_GT(emissions, 0)
+                << "the server counted no texture upload emission at all over " << kFrames
+                << " frames of " << kScatteredRects
+                << " sub-regions each plus a contiguous band. Either the uploads never reached the "
+                   "backend or the counter stopped counting; in both cases every shape number below "
+                   "would be a zero that means nothing. "
+                << window.line;
+
+            // 2. the server bracket's own arithmetic.
+            EXPECT_EQ(box + rect, emissions)
+                << "tex[box=] + tex[rect=] must be tex[emit=]: every emission takes exactly one of "
+                   "the two shapes. " << window.line;
+            EXPECT_GE(jobs, emissions)
+                << "tex[jobs=] must be at least tex[emit=]: a box emission is one driver upload job "
+                   "and a rect-list emission is N. " << window.line;
+
+            // 3. the two sides agree, WHEN THERE ARE TWO SIDES - and "there are two sides" is
+            //    answered by the BUILD, not by the number (review F-m7).
+            //
+            //    ctu= IS ALWAYS PRESENT IN A PUSH BUILD: PipeStats.cpp writes the field whether or
+            //    not anything ever incremented the counter, so `clientEmissions > 0` conflated
+            //    three different trees - "no client emitter exists", "the emitter exists and
+            //    emitted nothing", and "the counter was not published at all" - into one branch
+            //    that asserts nothing and prints a sentence that is only true of the first. Once
+            //    package B's texture emitter lands, an emitter that STOPPED emitting would read
+            //    exactly like no emitter at all and this case would have gone green over it, which
+            //    is the failure mode the whole scenario exists to make impossible.
+            //
+            //    So the discriminator is MGITEST_PIPE_CLIENT_TEXTURE_UPLOAD_EMITTER_PRESENT, the
+            //    build's own content probe for a MG_Impl/Pipe source that emits
+            //    CallClass::ClientTextureUploadEmissions - the same mechanism as every other arming
+            //    decision in this package - and each side of it asserts something real.
+            const bool clientEmitterExists =
+                BuildMarkerIsSet("MGITEST_PIPE_CLIENT_TEXTURE_UPLOAD_EMITTER_PRESENT");
+            ASSERT_GE(clientEmissions, 0)
+                << "the summary line carries no ctu= field at all, in a push build, where PipeStats "
+                   "publishes it unconditionally. The client half of the comparison cannot be read: "
+                << window.line;
+            RecordProperty("client_emitter_present", clientEmitterExists ? 1 : 0);
+            if (clientEmitterExists) {
+                EXPECT_GT(clientEmissions, 0)
+                    << "a MG_Impl/Pipe source emits CallClass::ClientTextureUploadEmissions on this "
+                       "tree, and the SERVER counted " << emissions
+                    << " texture upload emissions for this workload, but the client counted NONE. An "
+                       "emitter that has stopped emitting reads exactly like no emitter at all in "
+                       "this field, which is why this case asks the build rather than the number. "
+                    << window.line;
+                EXPECT_EQ(clientEmissions, emissions)
+                    << "the CLIENT counted " << clientEmissions
+                    << " texture upload records and the SERVER counted " << emissions
+                    << " for the same workload in the same window. The two counting the same records "
+                       "is the entire reason both are published (D-L): a divergence here is an "
+                       "emission-shape divergence that SSIM is blind to and that costs ~+6 ms/frame "
+                       "on Mali when it goes the wrong way. "
+                    << window.line;
+            } else {
+                // Not merely "not asserted": on a tree with no client emitter the counter must be
+                // ZERO, and a non-zero one would mean the probe is looking for the wrong symbol -
+                // i.e. that the arming decision above is wrong and every future run of this case
+                // is mis-armed.
+                EXPECT_EQ(clientEmissions, 0)
+                    << "no MG_Impl/Pipe source emits CallClass::ClientTextureUploadEmissions on this "
+                       "tree, yet the client counted " << clientEmissions
+                    << " of them. Something is incrementing that counter which this build's probe "
+                       "cannot see, so the probe is looking for the wrong symbol and this case's "
+                       "arming decision is unreliable in both directions. " << window.line;
+                std::cout << "[ TextureUploadShape ] no P4a client emitter has landed on this tree "
+                             "(the build's ClientTextureUploadEmissions probe found none), so this "
+                             "run records the SERVER shape only and pins ctu=0. That is the expected "
+                             "reading on the contract tree and it is not a divergence."
+                          << std::endl;
+                RecordProperty("client_side", "absent");
+            }
+
+            // The pixels, so that a recorded shape cannot be the shape of a workload that drew
+            // nothing.
+            EXPECT_TRUE(RegionIsMostly(lastScattered, kInset, lastScattered.Width() - kInset, kInset,
+                                       lastScattered.Height() - kInset, "green", 0.0,
+                                       "the scattered-rect atlas"));
+            EXPECT_TRUE(RegionIsMostly(lastContiguous, kInset, lastContiguous.Width() - kInset, kInset,
+                                       lastContiguous.Height() - kInset, "green", 0.0,
+                                       "the contiguous-band atlas"));
+        }
+
+    } // namespace
+} // namespace MGITest

MobileGL/MG_Pipe/DirtySurface.def

@@ -299,11 +299,16 @@
     /* begins with one of the ten words the pattern matched.                                */ \
     /*   UseProgram is bit 6's whole subject: the shutter is                                */ \
     /*     Mix(GetCurrentProgram()->GetLifetimeId(), GetLinkVersion()) and glUseProgram is  */  \
-    /*     what moves the object it reads through. Two call sites.                          */ \
+    /*     what moves the object it reads through. Two call sites. AND SINCE THE FABLE     */  \
+    /*     SEAM ROUND (F-1 / F-2) IT IS BITS 12 AND 14's TOO: set_sampler_views is         */  \
+    /*     resolved for the program in use and set_shader_images' window is the highest    */  \
+    /*     image unit the program in use names, so both shutters mix the same identity     */  \
+    /*     bit 6 reads, and a glUseProgram alone moves all three. Undecided for the same    */  \
+    /*     reason as bit 6 (the taint below), marked the same way.                          */  \
     /*   BindVertexArray is bit 5's, for the same reason one level down: the shutter mixes  */  \
     /*     the bound VAO's identity with its configuration version, and this is the bind.   */  \
     /*     Three call sites.                                                                */ \
-    X(UseProgram,                         NEW_SHADER)                                          \
+    X(UseProgram,                         NEW_SHADER|NEW_SAMPLER_VIEWS|NEW_SHADER_IMAGES)      \
     X(BindVertexArray,                    NEW_VERTEX_ELEMENTS)                                 \
     /* NOT NEW_SHADER, and the derivation refutes it outright rather than leaving it a      */  \
     /* judgement: this mutator writes m_boundProgramPipeline (plus the pipeline name table) */  \
@@ -387,11 +392,12 @@
 // row nor outlive its reason.
 //
 // IT WAS EMPTY UNTIL P4a, and it stops being empty for a reason that is a property of the
-// SCANNER rather than of the two rows. Both entries below are bit answers that are plainly
-// true - glUseProgram is what moves the object bit 6's shutter reads through, and
-// glBindVertexArray is what moves the object bit 5's shutter reads through - and the write
-// analysis cannot say so, because each of them reaches, BY NAME, a body that writes a member
-// with no m_ prefix:
+// SCANNER rather than of the rows. Every entry below is a bit answer that is plainly true -
+// glUseProgram is what moves the object bits 6, 12 and 14's shutters read through (the
+// program in use; bits 12 and 14 since the fable seam round, F-1 / F-2), and glBindVertexArray
+// is what moves the object bit 5's shutter reads through - and the write analysis cannot say
+// so, because each of the two mutators reaches, BY NAME, a body that writes a member with no
+// m_ prefix:
 //
 //   UseProgram      -> DestroyProgramSlot() writes `attachedShaders`
 //   BindVertexArray -> a call spelled `Bind(` resolves to every body of that name, one of
@@ -403,13 +409,16 @@
 // never be claimed about code the script could not read. Widening the taint rule to ignore
 // non-m_ writes would weaken the one mechanism that catches a genuine under-fire, so the rows
 // are MARKED, with the tool's own reason, rather than the tool being made more permissive.
-// Control 9c is what proves a marked row still needs the mark, and control 18 is what fails
-// the moment either of these becomes decidable and the mark outlives its reason.
+// Control 21 is what proves every marked row still needs its mark (it reads this list, so a
+// row that gains a bit here is counted rather than assumed), and control 18 is what fails the
+// moment any of them becomes decidable and the mark outlives its reason.
 //
 // The ten mutators that reach a tainted body (--check prints the count) all carry a prose
-// answer, which no derivation checks; these two are the first that carry a bit answer.
+// answer, which no derivation checks; these two mutators are the first that carry a bit answer.
 #define MGP_DIRTY_SURFACE_UNDECIDED_LIST(X)                                                     \
     X(UseProgram,      NEW_SHADER)                                                              \
+    X(UseProgram,      NEW_SAMPLER_VIEWS)                                                       \
+    X(UseProgram,      NEW_SHADER_IMAGES)                                                       \
     X(BindVertexArray, NEW_VERTEX_ELEMENTS)
 
 // clang-format on

MobileGL/MG_Pipe/PipeApply.cpp

@@ -1094,6 +1094,32 @@ namespace MobileGL::MG_Pipe {
     void MGPipeSetResourceOps(const MGPipeResourceOps* ops) { g_resourceOps = ops; }
     const MGPipeResourceOps* MGPipeGetResourceOps() { return g_resourceOps; }
 
+    namespace {
+        // P4a's BELT (ID-39). See MGPipeApplierState::RefusedNoConsumer for the whole argument;
+        // in one line: acceptance is a contract with the client, and accepting a record on a
+        // backend that consumes none of them makes the emitter clear a dirty flag the legacy
+        // pull path still owed.
+        //
+        // IT IS THE SAME SIGNAL THE CLIENT'S GATE READS, deliberately - g_resourceOps is the
+        // table a backend installs at its own bring-up and uninstalls at teardown, and
+        // MGPipeApplierReset does NOT touch it (see there), so the gate cannot flap between a
+        // make-current and the emissions that follow it. The two therefore agree on every path
+        // except the one this exists for: an emitter called directly, without passing PipeFill.
+        //
+        // EVERY CALLER PLACES IT AFTER THE RECORD'S OWN SHAPE CHECKS AND BEFORE ANYTHING MOVES.
+        // A malformed record is Fatal{ProtocolCorruption} whether or not anything would have
+        // read it - a trip wire that fires only on some backends is a trip wire nobody can
+        // trust - so the refusal is the LAST thing asked and the first thing that stops the
+        // write. The three unit-set entry points are the exception and say so at their call
+        // site: ApplyUnitWindow validates and writes in one step, so the question has to be
+        // asked in front of it.
+        Bool NoP4aConsumer() {
+            if (g_resourceOps != nullptr) return false;
+            ++g_applier.RefusedNoConsumer;
+            return true;
+        }
+    } // namespace
+
     void MGPipeApplierReset() {
         g_applier.RenderStateCsos.clear();
         g_applier.BoundRenderStateCso = kMGPipeNullHandle;
@@ -1123,6 +1149,7 @@ namespace MobileGL::MG_Pipe {
         g_applier.RefusedResourceCalls = 0;
         g_applier.RefusedVertexInputCalls = 0;
         g_applier.RefusedObjectCalls = 0;
+        g_applier.RefusedNoConsumer = 0;
         g_applier.BoundVertexElements = kMGPipeNullHandle;
         g_applier.VertexBuffers = {};
         g_applier.VertexBufferStart = 0;
@@ -1553,6 +1580,15 @@ namespace MobileGL::MG_Pipe {
                                  kMGPipeMaxResourceSlots);
             return false;
         }
+        // P4a's belt, and only over the P4a half of this call: the BUFFER row is P3a's and its
+        // consumer question is the frontend's (MGPipeResourceSubsystemEnabled), which has
+        // already answered it before the emission - a buffer record can only arrive here on a
+        // backend that registered the table, so asking again would be a second copy of that
+        // rule in the one path that runs. A texture or renderbuffer create declined here leaves
+        // the client's publication latch at false, which is what makes the next respecify's
+        // self-healing create do the right thing if a table appears later.
+        if (desc.Target != kMGPipeResourceTargetBuffer && NoP4aConsumer()) return false;
+
         *record = MGPipeResourceRecord{};
         record->Gen = desc.Resource.Gen;
         record->Live = true;
@@ -1583,6 +1619,12 @@ namespace MobileGL::MG_Pipe {
                                  desc.Resource.Slot, desc.Resource.Gen, desc.GlNameForDiag, desc.Target);
             return false;
         }
+        // P4a's belt, for MGPipeApplyResourceCreate's reason and in front of the resolution
+        // rather than after it: with no consumer no create was ever accepted, so resolving
+        // first would report the absence as RefusedResourceCalls - the counter that means "a
+        // seam defect" - for a state that is by design.
+        if (desc.Target != kMGPipeResourceTargetBuffer && NoP4aConsumer()) return false;
+
         MGPipeResourceRecord* record = ResolveResourceIn(*table, "resource_respecify", desc.Resource);
         if (record == nullptr) return false;
         PinNoLiveHostWrites(*record, desc.Resource, "resource_respecify");
@@ -1711,6 +1753,10 @@ namespace MobileGL::MG_Pipe {
                                  static_cast<Uint32>(MGPipeSubDataUploadTargetOf(record.Target)));
             return false;
         }
+        // P4a's belt, AFTER the target fault above and before the upload is accumulated: this
+        // is the call whose acceptance clears a level's dirty flags (D-D5 / ID-18 M3), so it is
+        // the one that turned "no consumer" into lost texels on Magma.
+        if (NoP4aConsumer()) return false;
         return ApplyTextureUpload(record, bytes, regions);
     }
 
@@ -2200,6 +2246,14 @@ namespace MobileGL::MG_Pipe {
         // The surfaces' Res handles are not resolved either: an attachment PINS its texture,
         // and in monolith the frontend's own SharedPtr is that keep-alive, so a refusal here
         // would be enforcing a lifetime rule monolith cannot need and split has not defined.
+        // P4a's belt, after the record's own shape checks and before the table is touched. This
+        // entry point is the ONE the client can reach without passing PipeFill's gate -
+        // GL_Framebuffer.cpp's PipePublishFramebufferByName calls the emitter directly at the
+        // fifteen DSA sites - so on a backend with no consumer this is where those records
+        // stop. RefusedNoConsumer and not RefusedObjectCalls: the framebuffer family's counter
+        // contract (see the header) is that no framebuffer call ever moves that one.
+        if (NoP4aConsumer()) return;
+
         MGPipeFramebufferRecord* record =
             RecordAt(g_applier.FramebufferRecords, state.Fbo.Slot, kMGPipeMaxFramebufferSlots);
         // Unreachable: the bound was checked above, before anything moved. The null check is
@@ -2311,6 +2365,9 @@ namespace MobileGL::MG_Pipe {
                                  desc.Cso.Slot, desc.Cso.Gen, kMGPipeMaxSamplerCsoSlots);
             return;
         }
+        // P4a's belt, after the blob rule and the slot bound and before the record moves.
+        if (NoP4aConsumer()) return;
+
         MGPipeSamplerCsoRecord& record = *recordAt;
         // A CREATE STARTS THE RECORD OVER AND LEAVES Serial AT 0; A RE-ISSUE ON A LIVE IDENTITY
         // COUNTS UP. The first half is what stops a recycled slot contributing one field of its
@@ -2367,6 +2424,9 @@ namespace MobileGL::MG_Pipe {
                                  view.Cso.Slot, view.Cso.Gen, kMGPipeMaxSamplerViewSlots);
             return;
         }
+        // P4a's belt, after the slot bound and before the record moves.
+        if (NoP4aConsumer()) return;
+
         MGPipeSamplerViewRecord& record = *recordAt;
         // RE-ISSUING ON THE SAME HANDLE IS HOW A RESTRICTION CHANGE TRAVELS - a view is
         // identity-addressed one per texture object, minted off that object's lifetime id, and
@@ -2411,6 +2471,11 @@ namespace MobileGL::MG_Pipe {
     }
 
     void MGPipeApplySetTextureParams(const MGPTextureParams& params) {
+        // P4a's belt, and FIRST here because this call's first act is a resolution: with no
+        // consumer no texture create was accepted, so resolving would report the absence as
+        // RefusedObjectCalls - the counter that means a seam defect - for the designed state.
+        if (NoP4aConsumer()) return;
+
         // ADDRESSED BY RESOURCE AND BY NOTHING ELSE, which is the whole point of the call: a
         // texture that is only an FBO attachment, only an image-unit binding or only a
         // glCopyImageSubData endpoint has no sampler view to hang its parameters on, and the
@@ -2458,7 +2523,16 @@ namespace MobileGL::MG_Pipe {
     // unit with no texture carries a null resource. None of the three is resolved against a
     // record either - a set is WORKING STATE, the records it names are OBJECT state, and the
     // backend resolves the pair at its own sync point where both are current.
+    //
+    // P4a's belt sits IN FRONT of ApplyUnitWindow on all three, and this is the one place it
+    // is not last: ApplyUnitWindow validates the window and writes it in the same step, so
+    // there is no point between the two to stand at. The cost is that on a backend with no
+    // consumer a malformed window is declined rather than Fatal - which is the right trade the
+    // one way round it can be made, because that backend would never have been handed the
+    // window at all (the client's gate stops it) and the shipped configuration that DOES
+    // consume these still trips the wire.
     void MGPipeApplySetSamplerViews(const MGPSamplerViews& hdr, const MGPBoundView* tail) {
+        if (NoP4aConsumer()) return;
         if (!ApplyUnitWindow("set_sampler_views", hdr.Start, hdr.Count, hdr.ContentHash, tail,
                              g_applier.BoundSamplerViews, g_applier.SamplerViewStart,
                              g_applier.SamplerViewCount)) {
@@ -2468,6 +2542,7 @@ namespace MobileGL::MG_Pipe {
     }
 
     void MGPipeApplyBindSamplerStates(const MGPSamplerStates& hdr, const MGPipeHandle* tail) {
+        if (NoP4aConsumer()) return;
         if (!ApplyUnitWindow("bind_sampler_states", hdr.Start, hdr.Count, hdr.ContentHash, tail,
                              g_applier.BoundSamplerStates, g_applier.SamplerStateStart,
                              g_applier.SamplerStateCount)) {
@@ -2482,6 +2557,7 @@ namespace MobileGL::MG_Pipe {
         // sent and recast on the server - the record carries the application's format, and the
         // bind-format recast that turns a GL_RG32F bind into something 19 of 26 non-core
         // formats on Adreno will accept is the backend's, not this applier's.
+        if (NoP4aConsumer()) return;
         if (!ApplyUnitWindow("set_shader_images", hdr.Start, hdr.Count, hdr.ContentHash, tail,
                              g_applier.BoundShaderImages, g_applier.ShaderImageStart,
                              g_applier.ShaderImageCount)) {
@@ -2552,6 +2628,10 @@ namespace MobileGL::MG_Pipe {
         PinProgramArchiveRoundTrip(desc, *link, *spirv);
 #endif
 
+        // P4a's belt, after the blob rule, the slot bound and the verify round trip - all three
+        // are checks on the RECORD and stay honest on every backend - and before it is stored.
+        if (NoP4aConsumer()) return;
+
         MGPipeShaderCsoRecord& record = *recordAt;
         // A RE-ISSUE ON THE SAME HANDLE IS HOW A RELINK TRAVELS: the handle is minted per
         // frontend program and Gen moves only on slot reuse, so an existing record of the same
@@ -2583,6 +2663,11 @@ namespace MobileGL::MG_Pipe {
     void MGPipeApplyBindShaderState(const MGPHandleOnly& handle) {
         MOBILEGL_ASSERT(handle.Kind == static_cast<Uint32>(MGPipeKind::ShaderCso),
                         "bind_shader_state on kind %u", handle.Kind);
+        // P4a's belt, and first for set_texture_params' reason: with no consumer this applier
+        // holds no shader CSO record, so the resolution below would report the designed state
+        // as RefusedObjectCalls. The null-handle unbind is behind it too - a binding this
+        // applier never made is not one it may clear.
+        if (NoP4aConsumer()) return;
         // The null handle is legal and means "nothing bound", which is a GL state and not an
         // error; a DEAD handle leaves the previous binding untouched and is counted, which is
         // bind_render_state's precedent for the same question.
@@ -2639,6 +2724,7 @@ namespace MobileGL::MG_Pipe {
     void MGPipeApplySetDrawProgram(const MGPHandleOnly& handle) {
         MOBILEGL_ASSERT(handle.Kind == static_cast<Uint32>(MGPipeKind::ShaderCso),
                         "set_draw_program on kind %u", handle.Kind);
+        if (NoP4aConsumer()) return; // P4a's belt, for MGPipeApplyBindShaderState's reason.
         if (MGPipeHandleIsNull(handle.Handle)) {
             g_applier.DrawProgram = kMGPipeNullHandle;
             ++g_applier.ProgramBindingSerial;
@@ -2653,6 +2739,7 @@ namespace MobileGL::MG_Pipe {
     void MGPipeApplySetDispatchProgram(const MGPHandleOnly& handle) {
         MOBILEGL_ASSERT(handle.Kind == static_cast<Uint32>(MGPipeKind::ShaderCso),
                         "set_dispatch_program on kind %u", handle.Kind);
+        if (NoP4aConsumer()) return; // P4a's belt, for MGPipeApplyBindShaderState's reason.
         if (MGPipeHandleIsNull(handle.Handle)) {
             g_applier.DispatchProgram = kMGPipeNullHandle;
             ++g_applier.ProgramBindingSerial;
@@ -2668,6 +2755,12 @@ namespace MobileGL::MG_Pipe {
         // ON THE PROGRAM'S RECORD, not in the working state, and that is what makes it survive a
         // make-current: the block is (ShaderCso, Version) keyed and belongs to the program, not
         // to the context that last uploaded it.
+        //
+        // P4a's belt goes in front of the resolution for set_texture_params' reason, and it is
+        // in front of the fault block too because THIS call's bounds come out of the resolved
+        // program's own GlobalUboSize - there is nothing to validate against until the record
+        // is in hand.
+        if (NoP4aConsumer()) return;
         MGPipeShaderCsoRecord* stored = ResolveShaderCso("set_global_constants", record.ShaderCso);
         if (stored == nullptr) return;
 

MobileGL/MG_Pipe/PipeApply.h

@@ -523,6 +523,35 @@ namespace MobileGL::MG_Pipe {
         // that is Fatal{ProtocolCorruption}, not a dropped call.
         Uint64 RefusedObjectCalls = 0;
 
+        // P4a's BELT (ID-39): every call in one of the four families P4a migrates that this
+        // applier declined because NO BACKEND HAS REGISTERED MGPipeResourceOps - i.e. because
+        // nothing in this process consumes what the record publishes.
+        //
+        // WHY THE APPLIER ASKS A QUESTION ABOUT THE BACKEND AT ALL, when it is otherwise
+        // backend-neutral: acceptance is a CONTRACT WITH THE CLIENT since ID-18 M3. The
+        // emitters clear a texture level's dirty flags, advance their descriptor mirrors and
+        // latch their suppressors on the answer this applier returns, so an applier that
+        // accepts a record nothing will ever read makes the client forget work the legacy pull
+        // path still owed - which is exactly how 66 texture-upload-shaped DirectVulkan cases
+        // went red on the push build (ID-39). The client's own gate
+        // (MG_Impl/Pipe/PipeFill.cpp's FamilyIsLive) stops the emission upstream; this is the
+        // belt under it, so a record that reaches here by any other route - GL_Framebuffer.cpp's
+        // PipePublishFramebufferByName calls its emitter directly, without passing PipeFill -
+        // is declined rather than accepted.
+        //
+        // IT IS NOT A DEFECT COUNTER, WHICH IS WHY IT IS SILENT. RefusedResourceCalls,
+        // RefusedVertexInputCalls and RefusedObjectCalls each mean "a record named something
+        // this applier should have had"; a non-zero value there is a seam defect. A non-zero
+        // value HERE is the designed steady state of a backend with no P4a twins, so logging it
+        // would put an ERROR line in every ordinary Magma run. The number is the observable.
+        //
+        // THE DEATH PATHS ARE DELIBERATELY NOT ON THIS LIST. resource_destroy,
+        // delete_sampler_state, delete_sampler_view and delete_shader_state are idempotent
+        // cleanup that must keep working whatever the registration did, and with no consumer
+        // there is no record for them to find anyway (they count their own refusal). Per
+        // context and cleared by MGPipeApplierReset, like the three above it.
+        Uint64 RefusedNoConsumer = 0;
+
         // ---- working state: what the next draw fetches with. All of it is per context and
         // all of it is cleared by MGPipeApplierReset, EXCEPT the two serials, which only ever
         // advance (see there).

MobileGL/MG_Pipe/PipeMutation.h

@@ -56,7 +56,11 @@ namespace MobileGL::MG_Pipe {
     enum class MGPipeAggregate : Uint32 {
         // VertexArrayState: any VAO attribute format / buffer / enable moved.
         VaoAttribute = 0,
-        // FramebufferState: any FBO attachment or default-geometry write, or a bind.
+        // FramebufferState: any FBO attachment or default-geometry write, or a bind - and, since
+        // P4a (fable seam F-3), any STORAGE DEFINITION of a texture or a renderbuffer, because
+        // set_framebuffer_state inlines an attachment's format, extent and samples and those
+        // setters are the only writers of what it inlines (TextureObject.cpp /
+        // RenderbufferObject.cpp, PipePublishDescriptor).
         FramebufferAttachment,
         // TextureState: any texture object CONTENT moved (an upload, a dirty region).
         TextureContent,

MobileGL/MG_State/GLState/FramebufferState/FramebufferObject.cpp

@@ -25,15 +25,22 @@ namespace MobileGL::MG_State::GLState {
 
 #if MOBILEGL_PIPE_PUSH
     FramebufferObject::~FramebufferObject() {
-        // P2 step e2: ANNOUNCE the death instead of leaving the backend to discover it in a
-        // garbage sweep. This is the last SharedPtr to this object dropping - not the
-        // glDelete* that only marks the name and leaves a still-bound object very much
-        // alive - so it is the exact moment the backend's twin, and the driver storage
-        // that twin owns, stop being reachable. The notice carries the lifetime id
-        // because the object no longer exists to be passed, and because the lifetime id
-        // is what the client slot allocator resolves the handle from. No-op unless a
-        // backend registered the ops (a pull build declares none at all).
-        NotifyStateObjectDestroyed(MG_Pipe::MGPipeKind::Framebuffer, m_lifetimeId);
+        // P4a D-I2: A FRAMEBUFFER HAS A HANDLE AND NO WIRE LIFETIME. PipeCalls.def carries
+        // resource_destroy and five delete_* rows and NO framebuffer delete, because a
+        // framebuffer is not a resource and is not a CSO - it is STATE, and
+        // set_framebuffer_state is the only call that names one - and the catalogue is closed,
+        // so P4a invents no row. The helper is therefore steps 2 and 3 only: the death notice,
+        // raised while the handle still resolves (this is the P2 step-e2 announcement that used
+        // to stand here alone - the last SharedPtr to this object dropping, not the glDelete*
+        // that only marks the name and leaves a still-bound object very much alive), and then
+        // the slot.
+        //
+        // What makes a dangling Fbo unreachable is the frontend's own
+        // MarkFramebufferObjectForDeletion path, which already rebinds any slot holding the
+        // victim to framebuffer 0; and a RECYCLED framebuffer handle can never be suppressed
+        // against its predecessor's record, because Fbo carries Gen and Gen is inside the
+        // record's ContentHash.
+        MG_Pipe::MGPipeEmitFramebufferDestroyAndFree(m_lifetimeId);
     }
 #endif
 

MobileGL/MG_State/GLState/ProgramState/ProgramObject.cpp

@@ -14,6 +14,7 @@
 #include <MG_Util/Async/ShaderCompilePool.h>
 #include <MG_Util/Converters/GLToStr/GLEnumConverter.h>
 #include <MG_Util/ShaderTranspiler/CompileEnv.h>
+#include <MG_Pipe/PipeMutation.h>
 #include <MG_State/GLState/StateObjectDeathNotice.h>
 
 const char* kDefaultFragmentShaderSource = R"(#version 460 core
@@ -40,7 +41,21 @@ namespace MobileGL::MG_State::GLState {
         // object no longer exists to be passed, and because the lifetime id is what the client
         // slot allocator resolves the handle from. No-op unless a backend registered the ops
         // (a pull build declares none at all).
-        NotifyStateObjectDestroyed(MG_Pipe::MGPipeKind::ShaderCso, m_lifetimeId);
+        //
+        // P4a D-I1: the notice is no longer raised directly - it is step 2 of the ONE
+        // client-side death helper for this kind, which emits delete_shader_state first,
+        // raises the notice second and frees the slot last. The client mints the ShaderCso, so
+        // the client is where its death has to be spoken from: a backend death-ops table is a
+        // redundant, idempotent SECOND path, and under a backend that installs none it was
+        // previously the ONLY one, which is how a slot leaks for the life of the process.
+        //
+        // AN ORDINARY PROGRAM AND A PIPELINE COMPOSITE TAKE THIS SAME LINE. A composite is an
+        // ordinary ProgramObject with its own lifetime id, its slot merely comes out of the
+        // reserved band, and its OTHER release path - the pipeline cache dropping it when the
+        // draw-program signature moves - goes through the same helper. Whichever runs second is
+        // a proven no-op, because the slot allocator refuses a slot that is not live at that
+        // generation.
+        MG_Pipe::MGPipeEmitShaderCsoDestroyAndFree(m_lifetimeId);
 #endif
     }
 

MobileGL/MG_State/GLState/ProgramState/ProgramObject.h

@@ -1111,6 +1111,23 @@ namespace MobileGL::MG_State::GLState {
             return Artifacts();
         }
 
+#if MOBILEGL_PIPE_PUSH
+        // The phase-B twin of GetLinkReflection, and it exists for exactly one caller:
+        // create_shader_state publishes the WHOLE SpirvArtifacts beside the whole
+        // LinkArtifacts, because the archive the far side deserialises into is those two
+        // structs and nothing else. The granular getters above (GetGeneratedSpirv,
+        // GetSpirvStatus, UsesNativeFloat64, PointSizeDemoted, GetSpirvValidationEnabled,
+        // GetUBOSize) cover what the GL layer needs and deliberately do not reach
+        // reservedNumSamplesOffset or uniformOffsets, which the descriptor does need.
+        //
+        // PUSH-ONLY, so a pull build's symbol set and this class's layout are byte-for-byte
+        // what they were: an inline const-ref accessor adds nothing to a pull build that is
+        // never compiled into one. It joins both phases, like every other Spirv() reader.
+        const SpirvArtifacts& GetSpirvReflection() const {
+            return Spirv();
+        }
+#endif
+
         static Bool IsValidUniformLocation(const LinkArtifacts& artifacts, Int location) {
             if (location < 0 || location > static_cast<Int>(artifacts.maxUniformLocation)) return false;
             if (static_cast<SizeT>(location) >= artifacts.uniformIndexInTProgram.size()) return false;

MobileGL/MG_State/GLState/RenderbufferState/RenderbufferObject.cpp

@@ -9,6 +9,10 @@
 #include "RenderbufferObject.h"
 #include <MG_Util/Metrics/TextureMetrics.h>
 #include <MG_State/GLState/StateObjectDeathNotice.h>
+// The contract's own door, exactly as the texture half takes it (c0b): the four renderbuffer
+// hooks this file calls are declared in MG_Pipe/PipeMutation.h and defined in
+// MG_Impl/Pipe/PipeFill.cpp, so no MG_State translation unit includes the client's emitter.
+#include <MG_Pipe/PipeMutation.h>
 
 #include <atomic>
 
@@ -25,19 +29,33 @@ namespace MobileGL {
                 return g_nextRenderbufferLifetimeId.fetch_add(1, std::memory_order_relaxed);
             }
 
-            RenderbufferObject::RenderbufferObject(Uint externalIndex) : m_externalIndex(externalIndex) {}
+            RenderbufferObject::RenderbufferObject(Uint externalIndex) : m_externalIndex(externalIndex) {
+#if MOBILEGL_PIPE_PUSH
+                // P4a D-D1: resource_create from the constructor, carrying no storage. A
+                // renderbuffer is an INDEPENDENT class on the wire - it shares MGPResourceDesc's
+                // shape with textures and buffers and nothing else - and its handle is minted
+                // whatever the subsystem bitmask says, because MGPSurface::Res names it out of the
+                // framebuffer subsystem.
+                // TWO CALLS AND NOT ONE (c0b): the mint is unconditional in a push build
+                // because a renderbuffer is named by handle out of the framebuffer subsystem
+                // whether or not its own family is switched on; the create is what the gate in
+                // PipeFill.cpp decides.
+                MG_Pipe::MGPipeMintRenderbufferHandle(*this);
+                MG_Pipe::MGPipeEmitRenderbufferResourceCreate(*this);
+#endif
+            }
 
 #if MOBILEGL_PIPE_PUSH
             RenderbufferObject::~RenderbufferObject() {
-                // P2 step e2: ANNOUNCE the death instead of leaving the backend to discover it in a
-                // garbage sweep. This is the last SharedPtr to this object dropping - not
-                // glDeleteRenderbuffers, which only marks the name and leaves a still-bound object very much
-                // alive - so it is the exact moment the backend's twin, and the driver storage that
-                // twin owns, stop being reachable. The notice carries the lifetime id because the
-                // object no longer exists to be passed, and because the lifetime id is what the client
-                // slot allocator resolves the handle from. No-op unless a backend registered the ops
-                // (a pull build declares none at all).
-                NotifyStateObjectDestroyed(MG_Pipe::MGPipeKind::Renderbuffer, m_lifetimeId);
+                // P4a D-I1, the fixed three-step order: the wire delete first (published-gated,
+                // because a slot is not evidence of a record), then the death notice - the P2
+                // step-e2 announcement that used to stand here alone, raised while the handle
+                // still resolves - and the slot last. Steps 2 and 3 are the contract's helper;
+                // step 1 is this package's, one statement earlier, because the helper's file
+                // belongs to the contract package for the whole phase.
+                // All three steps are the contract's helper (c0b); v1's separate step-1 call
+                // is deleted, not kept, for the reason ~TextureObjectBase states in full.
+                MG_Pipe::MGPipeEmitRenderbufferDestroyAndFree(m_lifetimeId);
             }
 #endif
 
@@ -96,17 +114,53 @@ namespace MobileGL {
             void RenderbufferObject::SetInternalFormat(TextureInternalFormat format) {
                 m_internalFormat = format;
                 m_componentSizes = MG_Util::GetComponentSizesForInternalFormat(format);
+#if MOBILEGL_PIPE_PUSH
+                PipePublishDescriptor();
+#endif
             }
 
             void RenderbufferObject::AllocateStorage(IntVec2 size) {
                 m_width = size.x();
                 m_height = size.y();
                 m_allocated = true;
+#if MOBILEGL_PIPE_PUSH
+                PipePublishDescriptor();
+#endif
             }
 
             void RenderbufferObject::SetSamples(Int samples) {
                 m_samples = samples;
+#if MOBILEGL_PIPE_PUSH
+                PipePublishDescriptor();
+#endif
             }
+
+#if MOBILEGL_PIPE_PUSH
+            // D-D2: THE RENDERBUFFER PUBLICATION HOLE, CLOSED BY EMISSION AND NOT BY A NEW
+            // VERSION. These three setters bump no version and raise no notice, so
+            // `glBindRenderbuffer; glRenderbufferStorage(newSize)` on an attached renderbuffer
+            // was invisible to everything downstream. Emitting from the storage entry point
+            // closes the RESOURCE half; a version counter here would resize the pull build's
+            // object and break G1.
+            //
+            // THE FRAMEBUFFER HALF IS THE AGGREGATE BUMP BELOW (P4a fable seam F-3), and the
+            // sentence that used to end the paragraph above - "widening the shutter would fire
+            // the framebuffer emission on an unrelated renderbuffer write" - was the seam:
+            // set_framebuffer_state inlines an attachment's InternalFormat, extent and Samples at
+            // emission (D-C1), so re-storaging an ATTACHED renderbuffer left the framebuffer
+            // record - and the handle arm's four cross-object masks - describing the previous
+            // storage while the resource record described the new one. The bump costs one
+            // framebuffer re-emission per storage definition, whether or not the object is
+            // attached, which the emitter's content hash suppresses when nothing it inlines
+            // moved; it is not a counter on this object.
+            //
+            // The emitter dedupes on the built descriptor, so glRenderbufferStorage's three-setter
+            // sequence publishes once rather than three times.
+            void RenderbufferObject::PipePublishDescriptor() {
+                MG_Pipe::MGPipeEmitRenderbufferResourceRespecify(*this);
+                MGP_NOTE_AGGREGATE(FramebufferAttachment);
+            }
+#endif
         } // namespace GLState
     } // namespace MG_State
 } // namespace MobileGL

MobileGL/MG_State/GLState/RenderbufferState/RenderbufferObject.h

@@ -59,6 +59,13 @@ namespace MobileGL {
 
             private:
                 static Uint64 AllocateLifetimeId();
+#if MOBILEGL_PIPE_PUSH
+                // P4a D-D2: resource_respecify, from every storage-defining setter. Non-virtual
+                // and push-only, so the pull build's object layout is untouched (P4a's
+                // admitted-resize set is EMPTY); defined in RenderbufferObject.cpp, which is the
+                // one translation unit that includes the client emitter.
+                void PipePublishDescriptor();
+#endif
 
                 Uint m_externalIndex = 0;
                 const Uint64 m_lifetimeId = AllocateLifetimeId();

MobileGL/MG_State/GLState/SamplerState/SamplerObject.cpp

@@ -36,7 +36,22 @@ namespace MobileGL {
                 // because the object no longer exists to be passed, and because the lifetime id
                 // is what the client slot allocator resolves the handle from. No-op unless a
                 // backend registered the ops (a pull build declares none at all).
-                NotifyStateObjectDestroyed(MG_Pipe::MGPipeKind::SamplerCso, m_lifetimeId);
+                //
+                // P4a D-I1: the notice is no longer raised directly - it is step 2 of the ONE
+                // client-side death helper for this kind, which emits delete_sampler_state
+                // first, raises the notice second and frees the slot last. Making the client
+                // the only death path is what stops a slot leaking under a backend that
+                // installs no death-ops table at all, and the backend's own notice becomes a
+                // redundant, idempotent second path rather than the only one.
+                //
+                // FOR A CONTENT-ADDRESSED SAMPLER CSO THIS HELPER CORRECTLY FREES NOTHING, and
+                // that is the design rather than a gap: the CSO belongs to a VALUE, not to this
+                // object (two identical SamplerObjects share one), so it is allocated with no
+                // lifetime id, the helper resolves nothing for this one, and the only death
+                // path for that slot is the CSO cache's LRU eviction - which is client-side and
+                // therefore backend-neutral on day one. What still goes out, unconditionally
+                // and exactly as before, is the notice.
+                MG_Pipe::MGPipeEmitSamplerCsoDestroyAndFree(m_lifetimeId);
             }
 #endif
 

MobileGL/MG_State/GLState/TextureState/TextureObject.cpp

@@ -12,6 +12,13 @@
 #include "MG_Util/Types.h"
 #include <MG_Util/Metrics/TextureMetrics.h>
 #include <MG_Pipe/PipeMutation.h>
+// NO MG_State TRANSLATION UNIT SEES THE CLIENT'S EMITTER ANY MORE (c0b, ID-13). v1 included
+// MG_Impl/Pipe/TextureEmit.h here and in RenderbufferObject.cpp because at the contract tag
+// MG_Pipe/PipeMutation.h carried no texture row; it now declares the four mints, the nine
+// emissions and the publication latch, so this file sees a DECLARATION exactly as
+// BufferObject.cpp does and the closure gate's mutation-header probe has nothing to find.
+// The three PipePublish* helpers stay on TextureObjectBase so the cube's, the view's and the
+// buffer texture's translation units keep calling an inherited member.
 
 namespace MobileGL {
     namespace MG_State {
@@ -29,15 +36,60 @@ namespace MobileGL {
 
 #if MOBILEGL_PIPE_PUSH
             TextureObjectBase::~TextureObjectBase() {
-                // P2 step e2: ANNOUNCE the death instead of leaving the backend to discover it in a
-                // garbage sweep. This is the last SharedPtr to this object dropping - not the
-                // glDelete* that only marks the name and leaves a still-bound object very much
-                // alive - so it is the exact moment the backend's twin, and the driver storage
-                // that twin owns, stop being reachable. The notice carries the lifetime id
-                // because the object no longer exists to be passed, and because the lifetime id
-                // is what the client slot allocator resolves the handle from. No-op unless a
-                // backend registered the ops (a pull build declares none at all).
-                NotifyStateObjectDestroyed(MG_Pipe::MGPipeKind::Texture, m_lifetimeId);
+                // P4a D-I1: BACKEND-NEUTRAL FROM DAY ONE, and the three-step order is fixed.
+                //
+                //   1. the wire delete FIRST - it drops the applier's record while the record
+                //      still exists, so a recycled slot cannot inherit a field. Published-gated
+                //      rather than slot-gated: a backend twin table mints a slot through
+                //      MGPipeSlots().Acquire whether or not the subsystem ever asked this client
+                //      to emit a create, and a resource_destroy on such a handle is a refused
+                //      call the applier counts and asserts on;
+                //   2. the death notice SECOND - it resolves the handle through the allocator,
+                //      and a backend told after the free could no longer find its twin. This is
+                //      the P2 step-e2 announcement that used to stand here alone: the last
+                //      SharedPtr to this object dropping, not the glDelete* that only marks the
+                //      name and leaves a still-bound object very much alive;
+                //   3. the slot LAST, and a double free on a stale generation is a proven no-op.
+                //
+                // ALL THREE STEPS ARE THE CONTRACT'S HELPER (c0b): it reads the publication
+                // latch, emits the resource_destroy itself, raises the notice while the handle
+                // still resolves and frees the slot last. v1 emitted step 1 from a second
+                // statement here because at the tag the helper hard-coded `published = false`;
+                // that statement is deleted rather than kept, since a second delete for a
+                // record the helper has already dropped is a refused call the applier asserts
+                // on. The SamplerViewCso minted off this same lifetime id goes with it. The
+                // BUILT-IN SAMPLER does not: it is a real SamplerObject with its own lifetime
+                // id and its own destructor, which takes the same helper shape.
+                MG_Pipe::MGPipeEmitTextureDestroyAndFree(m_lifetimeId);
+            }
+
+            // ---- P4a's three client emission points (see TextureObject.h) ----
+
+            void TextureObjectBase::PipePublishDescriptor() {
+                MG_Pipe::MGPipeEmitTextureResourceRespecify(*this);
+                // AND THE FRAMEBUFFER AGGREGATE MOVES (P4a fable seam F-3). The resource record
+                // above is only half of what a storage definition changes: set_framebuffer_state
+                // INLINES an attachment's InternalFormat, TextureTarget, extent, Samples and
+                // Complete at emission (D-C1), so redefining the storage of a texture that is
+                // ATTACHED changed those fields with nothing bit 11 reads moving - the format
+                // and shape setters bump the two TEXTURE aggregates and never the attachment
+                // one, and no path from a texture reaches its framebuffers. The handle arm then
+                // answered its four cross-object masks from the stale copy while the legacy arm
+                // re-read the frontend at the same re-sync. This is the one funnel every
+                // storage-defining entry point takes (see AllocateStorage), so the bump lives
+                // here and not per setter, it is push-only like the rest of this block, and it
+                // over-fires the framebuffer bit once per storage definition of an unattached
+                // texture - at load time, where a 304-byte hash is nothing.
+                MGP_NOTE_AGGREGATE(FramebufferAttachment);
+            }
+
+            void TextureObjectBase::PipePublishParams() {
+                MG_Pipe::MGPipeEmitTextureParams(*this);
+            }
+
+            void TextureObjectBase::PipeNoteLevelDirty(TextureUploadTarget uploadTarget, Uint mipmapLevel) {
+                MG_Pipe::MGPipeNoteTextureLevelDirty(*this, static_cast<Uint32>(uploadTarget),
+                                                     static_cast<Uint32>(mipmapLevel));
             }
 #endif
 
@@ -69,6 +121,34 @@ namespace MobileGL {
                     m_sampler->SetWrapT(SamplerWrapMode::ClampToEdge);
                     m_sampler->SetWrapR(SamplerWrapMode::ClampToEdge);
                 }
+#if MOBILEGL_PIPE_PUSH
+                // P4a D-D1: A RESOURCE EXISTS BEFORE ANYTHING CAN NAME IT, so resource_create is
+                // emitted from the constructor and carries no storage - the store is defined
+                // lazily by the first respecify and every backend already tolerates a resource
+                // with none. The handle itself is minted whatever the subsystem bitmask says,
+                // because set_framebuffer_state and set_sampler_views name this texture by handle
+                // out of two different subsystems.
+                //
+                // NOTHING THE DERIVED CLASS IMPLEMENTS IS TOUCHED HERE and that is a
+                // correctness requirement rather than a style: the derived object does not exist
+                // yet, so ITextureObject::GetStorageType and ::GetUploadTargets - PURE, with no
+                // body on this base - would be undefined behaviour. The emitter reads GetTarget()
+                // and GetExternalIndex(), which TextureObjectBase itself overrides and which
+                // therefore dispatch to this class's own bodies over members the mem-init list
+                // has already written; the storage kind is derived from the target, which is
+                // exact (TextureObjectBuffer is the only class that reports Buffer and
+                // TextureBuffer is the only target it is constructed with).
+                //
+                // TWO CALLS AND NOT ONE (c0b): the MINT is unconditional in a push build -
+                // set_framebuffer_state and set_sampler_views name this texture by handle out of
+                // two other subsystems, so gating it would make them emit null handles in exactly
+                // the A/B arm that exists to isolate the families - and the CREATE is what the
+                // subsystem gate in PipeFill.cpp decides.
+                (void)target;
+                (void)externalIndex;
+                MG_Pipe::MGPipeMintTextureHandle(*this);
+                MG_Pipe::MGPipeEmitTextureResourceCreate(*this);
+#endif
             }
 
             TextureInternalFormat TextureObjectBase::GetFormat() const {
@@ -116,6 +196,14 @@ namespace MobileGL {
                 BumpShapeVersion();
                 ++m_textureParamsVersion;
                 MGP_NOTE_AGGREGATE(TextureParams);
+#if MOBILEGL_PIPE_PUSH
+                // The format is BOTH halves: a descriptor field the backend allocates from and a
+                // parameter the swizzle / depth-stencil push reads, so both records move. It is
+                // also the last statement of both glTexBuffer entry points, which is what
+                // publishes a buffer texture's window without a call site in MG_Impl/GLImpl.
+                PipePublishDescriptor();
+                PipePublishParams();
+#endif
             }
 
             Uint TextureObjectBase::GetExternalIndex() const {
@@ -142,6 +230,9 @@ namespace MobileGL {
                 m_sampler->SetBorderColor(color);
                 ++m_textureParamsVersion;
                 MGP_NOTE_AGGREGATE(TextureParams);
+#if MOBILEGL_PIPE_PUSH
+                PipePublishParams();
+#endif
             }
 
             const IntVec4& TextureObjectBase::GetBorderColorI() const {
@@ -157,6 +248,9 @@ namespace MobileGL {
                 m_sampler->SetBorderColorI(color);
                 ++m_textureParamsVersion;
                 MGP_NOTE_AGGREGATE(TextureParams);
+#if MOBILEGL_PIPE_PUSH
+                PipePublishParams();
+#endif
             }
 
             const UintVec4& TextureObjectBase::GetBorderColorUI() const {
@@ -172,6 +266,9 @@ namespace MobileGL {
                 m_sampler->SetBorderColorUI(color);
                 ++m_textureParamsVersion;
                 MGP_NOTE_AGGREGATE(TextureParams);
+#if MOBILEGL_PIPE_PUSH
+                PipePublishParams();
+#endif
             }
 
             BorderColorForm TextureObjectBase::GetBorderColorForm() const {
@@ -222,6 +319,9 @@ namespace MobileGL {
                 }
                 ++m_textureParamsVersion;
                 MGP_NOTE_AGGREGATE(TextureParams);
+#if MOBILEGL_PIPE_PUSH
+                PipePublishParams();
+#endif
             }
 
             void TextureObjectBase::SetSwizzleParamRGBA(const Vec4<TextureSwizzleParam>& values) {
@@ -230,6 +330,9 @@ namespace MobileGL {
                 m_swizzleParams = values;
                 ++m_textureParamsVersion;
                 MGP_NOTE_AGGREGATE(TextureParams);
+#if MOBILEGL_PIPE_PUSH
+                PipePublishParams();
+#endif
             }
 
             const UintVec2& TextureObjectBase::GetLevelRange() const {
@@ -249,6 +352,12 @@ namespace MobileGL {
                 ++m_textureParamsVersion;
                 MGP_NOTE_AGGREGATE(TextureParams);
                 BumpShapeVersion();
+#if MOBILEGL_PIPE_PUSH
+                // The level range is PARAMS, not a descriptor field: the record carries
+                // BaseLevel / MaxLevel and the storage is untouched. The descriptor is deduped on
+                // its own bytes, so the shape bump above costs nothing here.
+                PipePublishParams();
+#endif
             }
 
             void TextureObjectBase::SetMaxLevel(Uint maxLevel) {
@@ -261,6 +370,9 @@ namespace MobileGL {
                 ++m_textureParamsVersion;
                 MGP_NOTE_AGGREGATE(TextureParams);
                 BumpShapeVersion();
+#if MOBILEGL_PIPE_PUSH
+                PipePublishParams();
+#endif
             }
 
             Bool TextureObjectBase::IsImmutable() const {
@@ -281,6 +393,14 @@ namespace MobileGL {
                 }
                 ++m_textureParamsVersion;
                 MGP_NOTE_AGGREGATE(TextureParams);
+#if MOBILEGL_PIPE_PUSH
+                // Immutable is a descriptor fact the backend reads - and NOT a request for an
+                // acknowledgement: MGPipeResourceRespecifyNeedsAck names the buffer target
+                // explicitly, because texture allocation is lazy in monolith and stays lazy in
+                // split. The level clamp above is params.
+                PipePublishDescriptor();
+                PipePublishParams();
+#endif
             }
 
             Uint16 TextureObjectBase::GetTextureParamsVersion() const {
@@ -319,6 +439,9 @@ namespace MobileGL {
                 m_samples = samples;
                 ++m_textureParamsVersion;
                 MGP_NOTE_AGGREGATE(TextureParams);
+#if MOBILEGL_PIPE_PUSH
+                PipePublishDescriptor();
+#endif
             }
 
             Bool TextureObjectBase::HasFixedSampleLocations() const {
@@ -329,6 +452,9 @@ namespace MobileGL {
                 m_fixedSampleLocations = fixedSampleLocations;
                 ++m_textureParamsVersion;
                 MGP_NOTE_AGGREGATE(TextureParams);
+#if MOBILEGL_PIPE_PUSH
+                PipePublishDescriptor();
+#endif
             }
 
             Uint64 TextureObjectBase::GetLifetimeId() const {
@@ -360,11 +486,23 @@ namespace MobileGL {
                                                              MipmapInput input) {
                 BumpShapeVersion();
                 m_textureStorage.AllocateLevel(GetIndexOfTextureUploadTarget(uploadTarget), mipmapLevel, input);
+#if MOBILEGL_PIPE_PUSH
+                // AFTER the allocation, never before: BumpShapeVersion runs first and a descriptor
+                // built there would describe the level set this call is about to change. Every
+                // storage-defining GL entry point - glTexImage*, glCompressedTexImage*,
+                // glTexStorage*, glTextureView and the generated-mip storage grow - reaches
+                // storage through here, which is what makes the emission complete without one call
+                // site per entry point in MG_Impl/GLImpl.
+                PipePublishDescriptor();
+#endif
             }
 
             void TextureObjectWithOneMipmap::TruncateMipmapLevels(TextureUploadTarget uploadTarget, Uint levelCount) {
                 BumpShapeVersion();
                 m_textureStorage.TruncateToLevelCount(GetIndexOfTextureUploadTarget(uploadTarget), levelCount);
+#if MOBILEGL_PIPE_PUSH
+                PipePublishDescriptor();
+#endif
             }
 
             void TextureObjectWithOneMipmap::UpdateMipmapSubData(TextureUploadTarget uploadTarget, Uint mipmapLevel,
@@ -383,6 +521,11 @@ namespace MobileGL {
                     MGP_NOTE_AGGREGATE(TextureContent);
                 }
                 m_textureStorage.MarkDirty(GetIndexOfTextureUploadTarget(uploadTarget), mipmapLevel, dirty);
+#if MOBILEGL_PIPE_PUSH
+                // THE DRAIN LIST HAS NO CLEAN ARM (see TextureEmit.h): a level that goes clean
+                // is collected at the next drain, whose first test is IsStorageDirty.
+                if (dirty) PipeNoteLevelDirty(uploadTarget, mipmapLevel);
+#endif
             }
 
             Bool TextureObjectWithOneMipmap::IsStorageDirty(TextureUploadTarget uploadTarget, Uint mipmapLevel) const {
@@ -395,6 +538,13 @@ namespace MobileGL {
                 MGP_NOTE_AGGREGATE(TextureContent);
                 m_textureStorage.MarkDirtyRegion(GetIndexOfTextureUploadTarget(uploadTarget), mipmapLevel, offset,
                                                  size);
+#if MOBILEGL_PIPE_PUSH
+                // THE DRAIN LIST IS KEYED ON THE STORAGE OWNER FOR FREE: TextureObjectView
+                // forwards this call to the OWNER's method after remapping the level and the
+                // region, so an upload through a view and an upload through the owner arrive here
+                // on the same object with the same owner-side coordinates.
+                PipeNoteLevelDirty(uploadTarget, mipmapLevel);
+#endif
             }
 
             MipmapDirtyRegion TextureObjectWithOneMipmap::GetStorageDirtyRegion(TextureUploadTarget uploadTarget,

MobileGL/MG_State/GLState/TextureState/TextureObject.h

@@ -190,6 +190,12 @@ namespace MobileGL::MG_State::GLState {
             m_depthStencilTextureMode = mode;
             ++m_textureParamsVersion;
             MGP_NOTE_AGGREGATE(TextureParams);
+#if MOBILEGL_PIPE_PUSH
+            // D-E3's whole point, at the one site that proves it: the depth-stencil mode of a
+            // texture that is ONLY the READ framebuffer's attachment reaches the driver, because
+            // set_texture_params is addressed by resource and is independent of every binding.
+            PipePublishParams();
+#endif
         }
 
     protected:
@@ -201,6 +207,34 @@ namespace MobileGL::MG_State::GLState {
         // otherwise invisible to such a memo (no bind moved).
         void BumpShapeVersion();
 
+#if MOBILEGL_PIPE_PUSH
+        // ---- P4a's client emission points (brief D-D1, D-D3, D-E1, D-I1) ----
+        //
+        // NON-VIRTUAL AND PUSH-ONLY, both deliberately: a virtual would grow the vtable and a
+        // member would grow the object, and P4a's admitted-resize set is EMPTY - every edit
+        // that reaches the pull build is inside this guard, so the pull build's symbol set is
+        // byte-for-byte the one it had before the phase.
+        //
+        // DECLARED HERE AND DEFINED IN TextureObject.cpp, which calls the contract's own hooks
+        // in MG_Pipe/PipeMutation.h - the same door BufferObject.cpp uses, and no MG_State
+        // translation unit sees MG_Impl/Pipe/TextureEmit.h at all (c0b, ID-13). They stay
+        // members rather than free calls so the cube's, the view's and the buffer texture's
+        // translation units keep calling an inherited helper.
+        //
+        // resource_respecify. Called from BumpShapeVersion and from the three parameter
+        // setters that move a DESCRIPTOR field without moving the shape (immutable levels,
+        // sample count, fixed sample locations). The emitter dedupes on the built descriptor,
+        // so an over-call costs one 88-byte compare and never an extra record.
+        void PipePublishDescriptor();
+        // set_texture_params, from every mutator that bumps m_textureParamsVersion.
+        void PipePublishParams();
+        // The sub-data DRAIN LIST's append, on a level's first dirty mark. There is no clean
+        // arm: the contract's hook (MG_Pipe/PipeMutation.h) carries no `dirty` flag, and a
+        // level that goes clean is collected at the next drain, where !IsStorageDirty is the
+        // first test EmitOneLevel makes.
+        void PipeNoteLevelDirty(TextureUploadTarget uploadTarget, Uint mipmapLevel);
+#endif
+
         const Uint m_externalIndex;
         const Uint64 m_lifetimeId;
         const TextureTarget m_target = TextureTarget::Unknown;

MobileGL/MG_State/GLState/TextureState/TextureObject2DCube.cpp

@@ -31,11 +31,20 @@ namespace MobileGL {
                                                       MipmapInput input) {
                 BumpShapeVersion();
                 m_textureStorage.AllocateLevel(GetIndexOfTextureUploadTarget(uploadTarget), mipmapLevel, input);
+#if MOBILEGL_PIPE_PUSH
+                // AFTER the allocation, for TextureObjectWithOneMipmap's reason: BumpShapeVersion
+                // runs first and a descriptor built there would describe the level set this call
+                // is about to change.
+                PipePublishDescriptor();
+#endif
             }
 
             void TextureObject2DCube::TruncateMipmapLevels(TextureUploadTarget uploadTarget, Uint levelCount) {
                 BumpShapeVersion();
                 m_textureStorage.TruncateToLevelCount(GetIndexOfTextureUploadTarget(uploadTarget), levelCount);
+#if MOBILEGL_PIPE_PUSH
+                PipePublishDescriptor();
+#endif
             }
 
             void TextureObject2DCube::UpdateMipmapSubData(TextureUploadTarget uploadTarget, Uint mipmapLevel,
@@ -53,6 +62,11 @@ namespace MobileGL {
                     MGP_NOTE_AGGREGATE(TextureContent);
                 }
                 m_textureStorage.MarkDirty(GetIndexOfTextureUploadTarget(uploadTarget), mipmapLevel, dirty);
+#if MOBILEGL_PIPE_PUSH
+                // SIX FACES, SIX BLOBS, SIX DRAIN KEYS: the upload target is the face, and it is
+                // what the sub-data record's Target byte carries beside the resource target.
+                if (dirty) PipeNoteLevelDirty(uploadTarget, mipmapLevel);
+#endif
             }
 
             bool TextureObject2DCube::IsStorageDirty(TextureUploadTarget uploadTarget, Uint mipmapLevel) const {
@@ -65,6 +79,9 @@ namespace MobileGL {
                 MGP_NOTE_AGGREGATE(TextureContent);
                 m_textureStorage.MarkDirtyRegion(GetIndexOfTextureUploadTarget(uploadTarget), mipmapLevel, offset,
                                                  size);
+#if MOBILEGL_PIPE_PUSH
+                PipeNoteLevelDirty(uploadTarget, mipmapLevel);
+#endif
             }
 
             MipmapDirtyRegion TextureObject2DCube::GetStorageDirtyRegion(TextureUploadTarget uploadTarget,

MobileGL/MG_State/GLState/TextureState/TextureObjectBuffer.h

@@ -29,6 +29,15 @@ namespace MobileGL {
                 void SetBufferRange(SizeT offset, SizeT size) {
                     m_bufferRangeOffset = offset;
                     m_bufferRangeSize = size;
+#if MOBILEGL_PIPE_PUSH
+                    // Both glTexBuffer entry points bind the backing buffer and then set the
+                    // window, so this is the first statement at which the descriptor's
+                    // BufferForTexBuffer / BufOffset / BufSize trio is complete. SetInternalFormat
+                    // publishes again one statement later and is deduped away when the format did
+                    // not move - which is exactly the case a re-attach of a DIFFERENT buffer at
+                    // the same format would otherwise fall through.
+                    PipePublishDescriptor();
+#endif
                 }
                 SizeT GetBufferRangeOffset() const { return m_bufferRangeOffset; }
                 // Resolved against the buffer's current size, so kWholeBuffer tracks it.

MobileGL/MG_State/GLState/TextureState/TextureObjectView.cpp

@@ -79,6 +79,18 @@ namespace MobileGL::MG_State::GLState {
         // to the view. GetImmutableLevels() forwards to the owner for the actual GL query, which
         // GL 4.6 core 8.18 defines as the ORIGINAL texture's value.
         SetImmutableLevels(numLevels);
+#if MOBILEGL_PIPE_PUSH
+        // ViewOf, and it is published from HERE rather than left to SetImmutableLevels above,
+        // which early-returns when the composed level count happens to be the base class's
+        // current value - a degenerate view (the spec's min() composition narrowed to zero
+        // levels) would otherwise never publish the one field that makes it a view. The
+        // descriptor is deduped on its own bytes, so the ordinary case pays one compare.
+        //
+        // ONE HOP ALWAYS REACHES STORAGE: glTextureView composes a view-of-a-view onto the ROOT
+        // at creation, which is what the spec's additive min-level rule describes and what the
+        // assertion above pins, so the owner named here is never itself a view.
+        PipePublishDescriptor();
+#endif
     }
 
     Uint TextureObjectView::GetImmutableLevels() const {

MobileGL/MG_Test/Pipe/CompositeResolverTest.cpp

@@ -50,8 +50,14 @@
 #include "Includes.h"
 #include <MG_Pipe/MGPipe.h>
 #if MOBILEGL_PIPE_PUSH
+#include "Init.h"
+#include <MG_Impl/GLImpl/Program/GL_Program.h>
+#include <MG_Impl/GLImpl/Program/GL_ProgramPipeline.h>
+#include <MG_Impl/Pipe/CompositeResolver.h>
+#include <MG_Impl/Pipe/ProgramEmit.h>
 #include <MG_Impl/Pipe/SlotAllocator.h>
 #include <MG_Pipe/PipeApply.h>
+#include <MG_State/GLState/Core.h>
 // create_shader_state takes the two artefact structs by pointer beside the record, so a case
 // that mints a composite record needs their definitions.
 #include <MG_State/GLState/ProgramState/ProgramArtifacts.h>
@@ -72,13 +78,24 @@ namespace {
     }
 
 #if MOBILEGL_PIPE_PUSH
-    std::string ReadLog() {
+    // `from` is a byte offset, and it exists because of the fork below: the library's log file
+    // is already open by the time a case runs, so the child's lines are APPENDED to it rather
+    // than written to a fresh file, and only what the child appended is this drive's evidence.
+    std::string ReadLog(std::streamoff from = 0) {
         std::ifstream in(g_logPath, std::ios::binary);
+        if (from > 0) in.seekg(from, std::ios::beg);
         std::ostringstream ss;
         ss << in.rdbuf();
         return ss.str();
     }
 
+    // Where the library's log file currently ends. Reading from here after the child has
+    // aborted gives exactly the lines that drive produced.
+    std::streamoff LogEnd() {
+        std::ifstream in(g_logPath, std::ios::binary | std::ios::ate);
+        return in ? static_cast<std::streamoff>(in.tellg()) : std::streamoff{0};
+    }
+
     // A fresh applier per case, BOTH SCOPES, and it takes both because there are two: a reset
     // is a make-current and deliberately KEEPS the object records, so a fixture that wants a
     // genuinely empty applier has to say the other one as well. Every case is its own process
@@ -104,8 +121,14 @@ namespace {
     template <class Body>
     ChildResult RunInChild(Body body) {
         ChildResult result;
-        std::error_code ec;
-        std::filesystem::remove(g_logPath, ec);
+        // THE LOG PATH IS NOT UNLINKED HERE, and that is what this helper had to learn when the
+        // client's cases landed in the same file as the applier's: main() calls
+        // MobileGL::Initialize(), so the library's log FILE* is already open on this path and
+        // fork() duplicates it. Removing the path would leave the child writing into a deleted
+        // inode and the parent reading an empty file - the child would still abort, and the
+        // assertion on WHAT it named could never see the line. So the log's end is remembered
+        // and only what the child appended is read back.
+        const std::streamoff before = LogEnd();
         std::fflush(nullptr);
         const pid_t pid = ::fork();
         if (pid < 0) return result;
@@ -116,7 +139,7 @@ namespace {
         int status = 0;
         if (::waitpid(pid, &status, 0) != pid) return result;
         result.Status = status;
-        result.Log = ReadLog();
+        result.Log = ReadLog(before);
         return result;
     }
 
@@ -347,6 +370,393 @@ TEST(CompositeResolver, ASlotAtTheShaderCsoLimitIsRefusedWhileTheLastBandSlotIsN
 #endif
 }
 
+#if !MOBILEGL_PIPE_PUSH
+// G2 requires the pull and push ctest name sets to be identical, name for name.
+#define MGL_COMPOSITE_RESOLVER_TEST_LIST(X)                                                        \
+    X(CompositeResolver, ACompositeIsMintedFromTheReservedBand)                                     \
+    X(CompositeResolver, ASignatureThatHasNotMovedReusesOneComposite)                               \
+    X(CompositeResolver, TwoPipelinesWithTheSameSignatureKeepTheirOwnComposite)                     \
+    X(CompositeResolver, EvictionThenDestructionFreesTheSlotExactlyOnce)                            \
+    X(CompositeResolver, DestructionThenEvictionFreesTheSlotExactlyOnce)                            \
+    X(CompositeResolver, ASignatureMoveAfterAMakeCurrentStillReleasesThroughTheResolver)         \
+    X(CompositeResolver, TwoContextsHoldingOnePipelineNameKeepTheirOwnComposites)                \
+    X(CompositeResolver, ADestroyedContextsEntryIsDroppedRatherThanReleasedASecondTime)
+
+#define MGL_DECLARE_PULL_SKIP(Suite, Name)                                                         \
+    TEST(Suite, Name) { GTEST_SKIP() << "compiled only under MOBILEGL_PIPE_PUSH"; }
+MGL_COMPOSITE_RESOLVER_TEST_LIST(MGL_DECLARE_PULL_SKIP)
+#undef MGL_DECLARE_PULL_SKIP
+#else
+
+namespace {
+    namespace GL = MobileGL::MG_Impl::GLImpl;
+    using GLContext = MG_State::GLState::GLContext;
+    using MG_State::GLState::ProgramObject;
+    using MG_State::GLState::ProgramPipelineObject;
+
+    struct ResolverScope {
+        ResolverScope() { Clear(); }
+        ~ResolverScope() {
+            GL::BindProgramPipeline(0);
+            GL::UseProgram(0);
+            Clear();
+        }
+        ResolverScope(const ResolverScope&) = delete;
+        ResolverScope& operator=(const ResolverScope&) = delete;
+
+        static void Clear() {
+            MGPipeProgramEmitterInstance().Reset();
+            MGPipeProgramEmitterInstance().ResetCounters();
+            MGPipeCompositeResolverInstance().ResetCounters();
+        }
+    };
+
+    GLContext& Ctx() { return *MG_State::pGLContext; }
+
+    const char* kVs = R"(#version 430 core
+out gl_PerVertex { vec4 gl_Position; };
+void main() { gl_Position = vec4(0.0, 0.0, 0.0, 1.0); }
+)";
+    const char* kFs = R"(#version 430 core
+out vec4 o_color;
+void main() { o_color = vec4(1.0); }
+)";
+    // A SECOND fragment stage, so a pipeline's draw-program signature can be made to move for
+    // real: ComputeDrawProgramSignature is the per-stage {lifetimeId, GetLinkVersion()} array,
+    // and a different ProgramObject is a different lifetime id.
+    const char* kFs2 = R"(#version 430 core
+out vec4 o_color;
+void main() { o_color = vec4(0.5); }
+)";
+
+    // Built by hand rather than through glCreateShaderProgramv, for ProgramPipelineCompositeTest's
+    // reason: that entry point detaches the shader right after linking, so a relink would leave
+    // the stage program with nothing to composite from.
+    GLuint MakeSeparableProgram(GLenum stage, const char* source) {
+        const GLuint shader = GL::CreateShader(stage);
+        GL::ShaderSource(shader, 1, &source, nullptr);
+        GL::CompileShader(shader);
+        const GLuint program = GL::CreateProgram();
+        GL::ProgramParameteri(program, GL_PROGRAM_SEPARABLE, GL_TRUE);
+        GL::AttachShader(program, shader);
+        GL::LinkProgram(program);
+        GLint linked = GL_FALSE;
+        GL::GetProgramiv(program, GL_LINK_STATUS, &linked);
+        EXPECT_EQ(linked, GL_TRUE) << "separable stage program did not link";
+        return program;
+    }
+
+    GLuint MakeBoundPipeline(GLuint vs, GLuint fs) {
+        GLuint pipeline = 0;
+        GL::GenProgramPipelines(1, &pipeline);
+        GL::BindProgramPipeline(pipeline);
+        GL::UseProgramStages(pipeline, GL_VERTEX_SHADER_BIT, vs);
+        GL::UseProgramStages(pipeline, GL_FRAGMENT_SHADER_BIT, fs);
+        GL::UseProgram(0);
+        return pipeline;
+    }
+
+    TEST(CompositeResolver, ACompositeIsMintedFromTheReservedBand) {
+        ResolverScope scope;
+        const GLuint vs = MakeSeparableProgram(GL_VERTEX_SHADER, kVs);
+        const GLuint fs = MakeSeparableProgram(GL_FRAGMENT_SHADER, kFs);
+        MakeBoundPipeline(vs, fs);
+
+        const SharedPtr<ProgramObject> composite = Ctx().GetProgramForDraw();
+        ASSERT_TRUE(composite) << "the frontend has to flatten the pipeline for this to mean anything";
+        // The composite is the one ProgramObject in the system with external index 0: it is
+        // deliberately not a named program, must not answer glIsProgram and must not consume a
+        // name, and glCreateProgram never returns 0.
+        EXPECT_TRUE(MGPipeProgramIsPipelineComposite(*composite));
+        EXPECT_EQ(composite->GetExternalIndex(), 0u);
+
+        ASSERT_GT(MGPipeProgramEmitterInstance().EmitShaderState(Ctx()), 0u);
+        const MGPipeHandle cso = MGPipeProgramEmitterInstance().DrawCso();
+        ASSERT_FALSE(MGPipeHandleIsNull(cso));
+        EXPECT_TRUE(MGPipeIsCompositeShaderSlot(cso.Slot))
+            << "a composite's slot comes out of the reserved band and nowhere else";
+        // AND IT IS AN ORDINARY create_shader_state. The server never learns it is a composite.
+        EXPECT_EQ(MGPipeProgramEmitterInstance().LastProgramDesc().Cso, cso);
+        EXPECT_TRUE(MGPipeProgramEmitterInstance().RecordIsPublished(cso));
+        EXPECT_EQ(MGPipeCompositeResolverInstance().GetCounters().Mints, 1u);
+    }
+
+    TEST(CompositeResolver, ASignatureThatHasNotMovedReusesOneComposite) {
+        ResolverScope scope;
+        const GLuint vs = MakeSeparableProgram(GL_VERTEX_SHADER, kVs);
+        const GLuint fs = MakeSeparableProgram(GL_FRAGMENT_SHADER, kFs);
+        MakeBoundPipeline(vs, fs);
+
+        ASSERT_GT(MGPipeProgramEmitterInstance().EmitShaderState(Ctx()), 0u);
+        const MGPipeHandle first = MGPipeProgramEmitterInstance().DrawCso();
+        ASSERT_FALSE(MGPipeHandleIsNull(first));
+        ASSERT_EQ(MGPipeProgramEmitterInstance().CreateCount(), 1u);
+
+        // The stage set did not move, so the frontend hands back the cached composite and the
+        // resolver reuses its handle - no second identity, no second record, and nothing
+        // released. THE KEY IS ComputeDrawProgramSignature's {lifetimeId, linkVersion} array
+        // and deliberately NOT GetBackendStateVersion, which a glUniform1i to a sampler moves
+        // and which used to rebuild the composite on every draw.
+        MGPipeProgramEmitterInstance().EmitShaderState(Ctx());
+        EXPECT_EQ(MGPipeProgramEmitterInstance().DrawCso(), first);
+        EXPECT_EQ(MGPipeProgramEmitterInstance().CreateCount(), 1u);
+        EXPECT_EQ(MGPipeCompositeResolverInstance().GetCounters().Releases, 0u);
+        EXPECT_GE(MGPipeCompositeResolverInstance().GetCounters().Reuses, 1u);
+    }
+
+    // [deviation] The brief names this case "TwoPipelinesWithTheSameSignatureShareOneComposite".
+    // Sharing one HANDLE between two pipeline objects is not implementable safely and the
+    // property that is true is the opposite one, so the case is named for what it asserts.
+    //
+    // The reason is the death path: a composite is an ordinary ProgramObject with its OWN
+    // lifetime id, and the client-side death helper resolves the handle FROM that lifetime id.
+    // Two composites sharing one handle would put only one of the two ids in the allocator's
+    // map, so the first ~ProgramObject would free a slot the second still names - a premature
+    // free that reappears later as slot theft, which is the exact class this whole band exists
+    // to prevent. The frontend does not share either: each ProgramPipelineObject carries its
+    // own one-slot draw-program cache, so two pipeline objects with identical stage sets are
+    // two composites in the frontend too.
+    TEST(CompositeResolver, TwoPipelinesWithTheSameSignatureKeepTheirOwnComposite) {
+        ResolverScope scope;
+        const GLuint vs = MakeSeparableProgram(GL_VERTEX_SHADER, kVs);
+        const GLuint fs = MakeSeparableProgram(GL_FRAGMENT_SHADER, kFs);
+
+        MakeBoundPipeline(vs, fs);
+        ASSERT_GT(MGPipeProgramEmitterInstance().EmitShaderState(Ctx()), 0u);
+        const MGPipeHandle firstCso = MGPipeProgramEmitterInstance().DrawCso();
+        ASSERT_FALSE(MGPipeHandleIsNull(firstCso));
+
+        MakeBoundPipeline(vs, fs); // a SECOND pipeline object, the same stage set
+        MGPipeProgramEmitterInstance().EmitShaderState(Ctx());
+        const MGPipeHandle secondCso = MGPipeProgramEmitterInstance().DrawCso();
+        ASSERT_FALSE(MGPipeHandleIsNull(secondCso));
+
+        EXPECT_NE(firstCso, secondCso);
+        EXPECT_TRUE(MGPipeIsCompositeShaderSlot(firstCso.Slot));
+        EXPECT_TRUE(MGPipeIsCompositeShaderSlot(secondCso.Slot));
+        // Both are still resolvable, which is the property a shared handle would have broken.
+        EXPECT_TRUE(MGPipeSlots().IsLive(MGPipeKind::ShaderCso, firstCso));
+        EXPECT_TRUE(MGPipeSlots().IsLive(MGPipeKind::ShaderCso, secondCso));
+    }
+
+    // THE TWO RELEASE ORDERS, driven at the level where both of them are representable. Either
+    // order frees the slot exactly once and the second call is a PROVEN no-op, because
+    // MGPipeSlotAllocator::Free refuses a slot that is not live at that generation and bumps no
+    // generation of its own - so a double release cannot skip a generation either.
+    TEST(CompositeResolver, EvictionThenDestructionFreesTheSlotExactlyOnce) {
+        ResolverScope scope;
+        constexpr Uint64 kCompositeLifetimeId = 918273645ull;
+        const Uint32 liveBefore = MGPipeSlots().LiveCount(MGPipeKind::ShaderCso);
+        const MGPipeHandle cso = MGPipeSlots().AllocateComposite(kCompositeLifetimeId);
+        ASSERT_FALSE(MGPipeHandleIsNull(cso));
+        ASSERT_TRUE(MGPipeIsCompositeShaderSlot(cso.Slot));
+        ASSERT_EQ(MGPipeSlots().LiveCount(MGPipeKind::ShaderCso), liveBefore + 1);
+
+        // 1. the pipeline cache drops it
+        MGPipeEmitShaderCsoDestroyAndFree(kCompositeLifetimeId);
+        EXPECT_FALSE(MGPipeSlots().IsLive(MGPipeKind::ShaderCso, cso));
+        EXPECT_EQ(MGPipeSlots().LiveCount(MGPipeKind::ShaderCso), liveBefore);
+        // 2. and then ~ProgramObject runs, and finds nothing to do
+        MGPipeEmitShaderCsoDestroyAndFree(kCompositeLifetimeId);
+        EXPECT_EQ(MGPipeSlots().LiveCount(MGPipeKind::ShaderCso), liveBefore);
+    }
+
+    TEST(CompositeResolver, DestructionThenEvictionFreesTheSlotExactlyOnce) {
+        ResolverScope scope;
+        constexpr Uint64 kCompositeLifetimeId = 918273646ull;
+        const Uint32 liveBefore = MGPipeSlots().LiveCount(MGPipeKind::ShaderCso);
+        const MGPipeHandle cso = MGPipeSlots().AllocateComposite(kCompositeLifetimeId);
+        ASSERT_FALSE(MGPipeHandleIsNull(cso));
+
+        // The mirror order, and it is the one that actually happens today: the frontend's
+        // one-slot cache drops its SharedPtr as it overwrites it, so ~ProgramObject usually
+        // runs first and the resolver's release is the second, redundant path.
+        MGPipeEmitShaderCsoDestroyAndFree(kCompositeLifetimeId);
+        EXPECT_FALSE(MGPipeSlots().IsLive(MGPipeKind::ShaderCso, cso));
+        MGPipeEmitShaderCsoDestroyAndFree(kCompositeLifetimeId);
+        EXPECT_EQ(MGPipeSlots().LiveCount(MGPipeKind::ShaderCso), liveBefore);
+
+        // And the slot really came back: the next composite is handed the same slot with a
+        // bumped generation, so the stale handle can never resolve to it.
+        const MGPipeHandle recycled = MGPipeSlots().AllocateComposite(kCompositeLifetimeId + 1);
+        EXPECT_EQ(recycled.Slot, cso.Slot);
+        EXPECT_NE(recycled.Gen, cso.Gen);
+        MGPipeSlots().Free(MGPipeKind::ShaderCso, recycled);
+    }
+
+    // THE RELEASE PATH THE TWO CASES ABOVE DO NOT TOUCH. Both of them call the death helper
+    // directly, so the resolver is not in the picture at all and its own release - the
+    // pipeline-cache path, the one the header says exists precisely because "usually" is not a
+    // contract - had no case of its own. This drives it, and it drives it AFTER A
+    // MAKE-CURRENT, which is where it used to be permanently disarmed:
+    //
+    //   Reset() cleared the entry's one flag; the next Observe took the reuse branch and
+    //   returned before anything could restore it; from then on ReleaseEntry saw !Live and
+    //   returned immediately - no delete_shader_state, no Free, no counter movement - and the
+    //   old composite's handle was simply overwritten out of the resolver. Nothing leaked
+    //   today only because the frontend's one-slot pipeline cache drops the last SharedPtr on
+    //   the overwrite, which is exactly the "a client that only reacted to destructors" case
+    //   the design refuses to rely on.
+    //
+    // The release obligation now lives in its own flag and a make-current does not touch it.
+    TEST(CompositeResolver, ASignatureMoveAfterAMakeCurrentStillReleasesThroughTheResolver) {
+        ResolverScope scope;
+        const GLuint vs = MakeSeparableProgram(GL_VERTEX_SHADER, kVs);
+        const GLuint fs = MakeSeparableProgram(GL_FRAGMENT_SHADER, kFs);
+        const GLuint pipeline = MakeBoundPipeline(vs, fs);
+
+        ASSERT_GT(MGPipeProgramEmitterInstance().EmitShaderState(Ctx()), 0u);
+        const MGPipeHandle first = MGPipeProgramEmitterInstance().DrawCso();
+        ASSERT_FALSE(MGPipeHandleIsNull(first));
+        ASSERT_TRUE(MGPipeIsCompositeShaderSlot(first.Slot));
+        ASSERT_TRUE(MGPipeSlots().IsLive(MGPipeKind::ShaderCso, first));
+        ASSERT_EQ(MGPipeCompositeResolverInstance().GetCounters().Releases, 0u);
+
+        // THE MAKE-CURRENT. This is exactly what PipeFill's FreshlyPrimed arm does, and it
+        // reaches MGPipeCompositeResolver::Reset() through the program emitter's own Reset().
+        MGPipeProgramEmitterInstance().Reset();
+        // ... followed by a draw whose stage set has NOT moved, which is the reuse branch.
+        MGPipeProgramEmitterInstance().EmitShaderState(Ctx());
+        EXPECT_EQ(MGPipeProgramEmitterInstance().DrawCso(), first)
+            << "the same stage set is the same composite and the same handle";
+        EXPECT_GE(MGPipeCompositeResolverInstance().GetCounters().Reuses, 1u);
+        EXPECT_EQ(MGPipeCompositeResolverInstance().GetCounters().Releases, 0u)
+            << "a reuse releases nothing";
+
+        // NOW THE STAGE SET REALLY MOVES: a different fragment stage program is a different
+        // lifetime id, so ComputeDrawProgramSignature moves and the frontend builds a second
+        // composite. The resolver has to speak the release for the first one.
+        const GLuint fs2 = MakeSeparableProgram(GL_FRAGMENT_SHADER, kFs2);
+        GL::UseProgramStages(pipeline, GL_FRAGMENT_SHADER_BIT, fs2);
+        GL::UseProgram(0);
+
+        MGPipeProgramEmitterInstance().EmitShaderState(Ctx());
+        const MGPipeHandle second = MGPipeProgramEmitterInstance().DrawCso();
+        ASSERT_FALSE(MGPipeHandleIsNull(second));
+        EXPECT_NE(second, first) << "a moved signature is a second composite with its own handle";
+        EXPECT_EQ(MGPipeCompositeResolverInstance().GetCounters().Releases, 1u)
+            << "the resolver's own release path, spoken after a make-current";
+        EXPECT_FALSE(MGPipeSlots().IsLive(MGPipeKind::ShaderCso, first))
+            << "and the first composite's slot really went back, exactly once";
+        EXPECT_TRUE(MGPipeSlots().IsLive(MGPipeKind::ShaderCso, second));
+    }
+
+    // THE RESOLVER IS A PROCESS SINGLETON AND A PIPELINE's GL NAME IS PER CONTEXT (C2-M1).
+    // GLContext owns m_programPipelines AND its own name generator m_programPipelineNames, so
+    // name N names two different ProgramPipelineObjects in two contexts, each with its own
+    // composite and its own handle. Keyed on the name alone, the first Observe after a
+    // make-current found the OTHER context's entry: the signature matched - two composites of
+    // the same stage set have the same signature, and here two default pipelines have the same
+    // all-zero one - while the handle could not, because two composites are two ProgramObjects
+    // with two lifetime ids. So it fell into ReleaseEntry and emitted delete_shader_state for a
+    // LIVE composite, cleared its publication latch and handed its band slot back while the
+    // frontend ProgramObject was still alive.
+    //
+    // DRIVEN AT THE RESOLVER RATHER THAN THROUGH GL, because one test process has one
+    // GLContext. Everything the case supplies is what the single production call site supplies:
+    // the context id is GLContext::GetTextureContextId()'s value, the two same-named pipeline
+    // objects are what two contexts hold, and the composites are ordinary ProgramObjects at
+    // external index 0 out of the reserved band, exactly as Core.cpp builds them.
+    TEST(CompositeResolver, TwoContextsHoldingOnePipelineNameKeepTheirOwnComposites) {
+        ResolverScope scope;
+        auto& resolver = MGPipeCompositeResolverInstance();
+        const LinkArtifacts link;
+        const SpirvArtifacts spirv;
+
+        constexpr Uint kSharedPipelineName = 9u;
+        constexpr Uint64 kContextA = 0x51A00001ull;
+        constexpr Uint64 kContextB = 0x51A00002ull;
+        const ProgramPipelineObject pipelineA{kSharedPipelineName};
+        const ProgramPipelineObject pipelineB{kSharedPipelineName};
+        const SharedPtr<ProgramObject> compositeA = MakeShared<ProgramObject>(0u);
+        const SharedPtr<ProgramObject> compositeB = MakeShared<ProgramObject>(0u);
+        ASSERT_TRUE(MGPipeProgramIsPipelineComposite(*compositeA));
+        ASSERT_EQ(pipelineA.GetExternalIndex(), pipelineB.GetExternalIndex());
+
+        const MGPipeHandle handleA = MGPipeSlots().AllocateComposite(compositeA->GetLifetimeId());
+        const MGPipeHandle handleB = MGPipeSlots().AllocateComposite(compositeB->GetLifetimeId());
+        ASSERT_NE(handleA, handleB);
+        for (const MGPipeHandle handle : {handleA, handleB}) {
+            MGPipeApplyCreateShaderState(CompositeDesc(handle, 0x3u), &link, &spirv);
+            MGPipeNoteHandlePublished(MGPipeKind::ShaderCso, handle);
+        }
+        const Uint64 releasesBefore = resolver.GetCounters().Releases;
+
+        EXPECT_EQ(resolver.Observe(kContextA, pipelineA, *compositeA, handleA), handleA);
+        // THE MAKE-CURRENT, which is what PipeFill's FreshlyPrimed arm reaches through the
+        // program emitter's own Reset()...
+        MGPipeProgramEmitterInstance().Reset();
+        // ... and then context B draws with ITS pipeline of the same name.
+        EXPECT_EQ(resolver.Observe(kContextB, pipelineB, *compositeB, handleB), handleB);
+
+        EXPECT_EQ(resolver.GetCounters().Releases, releasesBefore)
+            << "the other context's entry was released - it is not this pipeline's entry";
+        EXPECT_TRUE(MGPipeSlots().IsLive(MGPipeKind::ShaderCso, handleA))
+            << "A's band slot went back while A's composite ProgramObject was still alive";
+        EXPECT_TRUE(MGPipeHandleIsPublished(MGPipeKind::ShaderCso, handleA))
+            << "delete_shader_state went out for a live composite and cleared its latch";
+        EXPECT_TRUE(MGPipeSlots().IsLive(MGPipeKind::ShaderCso, handleB));
+
+        // AND BACK TO A. Its obligation stayed owed to its own context, so the unmoved
+        // signature is a reuse of the same handle and still nothing is released.
+        const Uint64 reusesBefore = resolver.GetCounters().Reuses;
+        MGPipeProgramEmitterInstance().Reset();
+        EXPECT_EQ(resolver.Observe(kContextA, pipelineA, *compositeA, handleA), handleA);
+        EXPECT_EQ(resolver.GetCounters().Reuses, reusesBefore + 1u);
+        EXPECT_EQ(resolver.GetCounters().Releases, releasesBefore);
+    }
+
+    // WHERE A DESTROYED CONTEXT's ENTRIES ARE RELEASED, and it is not in the resolver. The
+    // context's death drops m_programPipelines, which drops the ProgramPipelineObject, which
+    // drops the composite it cached; ~ProgramObject then runs the one client-side death helper
+    // and the band slot goes back EXACTLY ONCE. The resolver speaks no second delete - the
+    // entry can never be found again, and the allocator has erased the lifetime-id mapping
+    // anyway - and the next make-current DROPS the stranded entry, which is what keeps the
+    // vector bounded now that its key carries the context.
+    TEST(CompositeResolver, ADestroyedContextsEntryIsDroppedRatherThanReleasedASecondTime) {
+        ResolverScope scope;
+        auto& resolver = MGPipeCompositeResolverInstance();
+        const LinkArtifacts link;
+        const SpirvArtifacts spirv;
+
+        constexpr Uint kPipelineName = 11u;
+        constexpr Uint64 kDoomedContext = 0x51A00003ull;
+        // ResolverScope's Clear() has already run one Reset(), so every entry standing here has
+        // a live composite slot and nothing but this case's own entry can be swept below.
+        const SizeT sizeBefore = resolver.Size();
+        const Uint32 liveBefore = MGPipeSlots().LiveCount(MGPipeKind::ShaderCso);
+
+        const ProgramPipelineObject pipeline{kPipelineName};
+        SharedPtr<ProgramObject> composite = MakeShared<ProgramObject>(0u);
+        const MGPipeHandle handle = MGPipeSlots().AllocateComposite(composite->GetLifetimeId());
+        MGPipeApplyCreateShaderState(CompositeDesc(handle, 0x3u), &link, &spirv);
+        MGPipeNoteHandlePublished(MGPipeKind::ShaderCso, handle);
+        ASSERT_EQ(resolver.Observe(kDoomedContext, pipeline, *composite, handle), handle);
+        ASSERT_EQ(resolver.Size(), sizeBefore + 1u);
+        const Uint64 releasesBefore = resolver.GetCounters().Releases;
+        const Uint64 sweepsBefore = resolver.GetCounters().Sweeps;
+
+        // THE CONTEXT DIES: the last SharedPtr to its composite goes with its pipeline.
+        composite.reset();
+        EXPECT_FALSE(MGPipeSlots().IsLive(MGPipeKind::ShaderCso, handle))
+            << "~ProgramObject is the release path for this entry and it freed the slot";
+        EXPECT_FALSE(MGPipeHandleIsPublished(MGPipeKind::ShaderCso, handle))
+            << "and it took the publication latch with the delete";
+        EXPECT_EQ(MGPipeSlots().LiveCount(MGPipeKind::ShaderCso), liveBefore) << "exactly once";
+        EXPECT_EQ(resolver.GetCounters().Releases, releasesBefore)
+            << "the resolver spoke no release of its own for it";
+
+        // THE NEXT CONTEXT's FIRST VERB. The stranded entry is dropped, not released.
+        MGPipeProgramEmitterInstance().Reset();
+        EXPECT_EQ(resolver.GetCounters().Sweeps, sweepsBefore + 1u);
+        EXPECT_EQ(resolver.GetCounters().Releases, releasesBefore)
+            << "a dropped entry emits nothing and frees nothing - the obligation was discharged";
+        EXPECT_EQ(resolver.Size(), sizeBefore)
+            << "the vector is bounded by the pairs whose composite slot is actually live";
+    }
+} // namespace
+#endif // MOBILEGL_PIPE_PUSH
+
 int main(int argc, char** argv) {
     namespace fs = std::filesystem;
     const fs::path path =
@@ -358,6 +768,9 @@ int main(int argc, char** argv) {
     _putenv_s("MOBILEGL_LOG_FILE_PATH", g_logPath.c_str());
 #else
     setenv("MOBILEGL_LOG_FILE_PATH", g_logPath.c_str(), 1);
+#endif
+#if MOBILEGL_PIPE_PUSH
+    MobileGL::Initialize();
 #endif
     ::testing::InitGoogleTest(&argc, argv);
     const int rc = RUN_ALL_TESTS();

MobileGL/MG_Test/Pipe/FramebufferEmitTest.cpp

@@ -58,7 +58,15 @@
 #include <MG_Pipe/MGPipe.h>
 #if MOBILEGL_PIPE_PUSH
 #include <MG_Impl/Pipe/FramebufferEmit.h>
+#include <MG_Impl/Pipe/SetHashSuppressor.h>
 #include <MG_Pipe/PipeApply.h>
+#include <MG_State/GLState/Core.h>
+#include <MG_State/GLState/FramebufferState/FramebufferObject.h>
+#include <MG_State/GLState/RenderbufferState/RenderbufferObject.h>
+#include <MG_State/GLState/TextureState/TextureObject2D.h>
+#include <MG_State/GLState/TextureState/TextureObject2DCube.h>
+
+#include <algorithm>
 #endif
 
 using namespace MobileGL;
@@ -202,6 +210,570 @@ TEST(FramebufferEmit, TheEmitterIsOneNeverDestroyedProcessSingleton) {
 #endif
 }
 
+// ============================================================================
+// P4a package B's EMITTER-SIDE cases. The contract commit landed the file, its ctest
+// registration and one shape pin; the wire package's applier-side cases and these are disjoint
+// TEST bodies in one file, and a collision between them is resolved by UNION, never by
+// choosing a side.
+//
+// EVERY CASE FAILS BY FIELD NAME, never by a bare count: G7's scripted control stops the
+// conversion copying exactly one member (MGPSurface::Layered) and expects this suite to go red
+// NAMING that field, and a case that reported only "the records differ" could not answer it.
+// ============================================================================
+#if !MOBILEGL_PIPE_PUSH
+#define MGL_FRAMEBUFFER_EMIT_CLIENT_TEST_LIST(X)                                                   \
+    X(FramebufferEmit, EveryRecordsReadSurfaceComesFromItsOwnFramebuffersReadBuffer)               \
+    X(FramebufferEmit, OneObjectBoundToBothTargetsEmitsOneRecordWithTargetBoth)                    \
+    X(FramebufferEmit, ADrawBufferChangeAloneStillMovesTheContentHash)                             \
+    X(FramebufferEmit, ARecycledFramebufferHandleIsNeverSuppressedAgainstItsPredecessor)           \
+    X(FramebufferEmit, EveryAttachmentFieldSurvivesTheSurfaceConversion)                           \
+    X(FramebufferEmit, AnAttachmentPointAboveTheWireWidthIsRefusedNotTruncated)                    \
+    X(FramebufferEmit, ARestoragedAttachedRenderbufferPublishesItsNewExtent)                       \
+    X(FramebufferEmit, AnUnchangedBindingPairEmitsNothing)                                         \
+    X(FramebufferEmit, AFramebufferHandedOverByNameGetsANamedRecordWithoutMovingABinding)          \
+    X(FramebufferEmit, ANamedRecordIsSuppressedPerObjectAndNeverAgainstABoundRecord)               \
+    X(FramebufferEmit, ADrawBufferTokenAboveTheWireWidthIsRefusedNotTruncated)                     \
+    X(FramebufferEmit, ALayeredCubeAttachmentDoesNotAssertAFaceItCannotKnow)                       \
+    X(FramebufferEmit, EveryNonTexturePointCarriesTheUnknownSentinelsRatherThanZero)
+
+#define MGL_DECLARE_PULL_SKIP(Suite, Name)                                                         \
+    TEST(Suite, Name) { GTEST_SKIP() << "compiled only under MOBILEGL_PIPE_PUSH"; }
+MGL_FRAMEBUFFER_EMIT_CLIENT_TEST_LIST(MGL_DECLARE_PULL_SKIP)
+#undef MGL_DECLARE_PULL_SKIP
+#else
+namespace {
+    using GLContext = MG_State::GLState::GLContext;
+    using MG_State::GLState::FramebufferObject;
+    using MG_State::GLState::MipmapInput;
+    using MG_State::GLState::RenderbufferObject;
+    using MG_State::GLState::TextureObject2D;
+    using MG_State::GLState::TextureObject2DCube;
+
+    // AN RAII SCOPE RATHER THAN A gtest FIXTURE, for VertexInputEmitTest's reason, and it arms
+    // BOTH bits this family needs: the framebuffer bit for the emission itself, and the
+    // texture-resource bit because MGPSurface::Res names a texture or renderbuffer handle and
+    // bit 9 requires bit 10 for exactly that reason.
+    struct FramebufferScope {
+        FramebufferScope() {
+            m_previousPush = MG_Config::Features.PipePush;
+            // D-K2, ALL THREE ROWS THAT REACH THIS SUITE, because the client enforces them since
+            // S-3 / ID-41 and not only Espryt's Resolve*SubsystemArm: bit 9 requires bit 10
+            // (MGPSurface::Res names a texture or renderbuffer handle), bit 10 requires bit 11
+            // (MGPTextureParams::BuiltinSampler is a SamplerCso out of the sampler family's
+            // content-addressed cache) and bit 10 requires bit 7 (a buffer texture's
+            // BufferForTexBuffer names a Buffer handle, D-D1). Bit 7 changes nothing else here:
+            // this file constructs no BufferObject.
+            MG_Config::Features.PipePush |= kMGPipeSubsystemResources |
+                                            kMGPipeSubsystemFramebuffer |
+                                            kMGPipeSubsystemTextureResources |
+                                            kMGPipeSubsystemSamplers;
+            m_previousContext = Move(MG_State::pGLContext);
+            MG_State::pGLContext = MakeUnique<GLContext>();
+            MGPipeFramebufferEmitterInstance().ResetForTest();
+            MGPipeTextureEmitterInstance().ResetForTest();
+            MGPipeSetHashSuppressorInstance().InvalidateAll();
+            // The applier is a process singleton and its object records outlive a case; with both
+            // families' wired constants set the emissions actually land, so a case must start
+            // from an empty table (v1 armed the texture emitter here instead - ArmForTest is
+            // gone with the flip).
+            MGPipeApplierReset();
+            MGPipeApplierReleaseObjectRecords();
+        }
+        ~FramebufferScope() {
+            MGPipeFramebufferEmitterInstance().ResetForTest();
+            MGPipeTextureEmitterInstance().ResetForTest();
+            MGPipeSetHashSuppressorInstance().InvalidateAll();
+            MGPipeApplierReset();
+            MGPipeApplierReleaseObjectRecords();
+            MG_State::pGLContext.reset();
+            MG_State::pGLContext = Move(m_previousContext);
+            MG_Config::Features.PipePush = m_previousPush;
+        }
+        FramebufferScope(const FramebufferScope&) = delete;
+        FramebufferScope& operator=(const FramebufferScope&) = delete;
+
+        UniquePtr<GLContext> m_previousContext;
+        Uint64 m_previousPush = 0;
+    };
+
+    MGPipeFramebufferEmitter& Framebuffers() { return MGPipeFramebufferEmitterInstance(); }
+    GLContext& Ctx() { return *MG_State::pGLContext; }
+
+    SharedPtr<TextureObject2D> MakeColorTexture(Uint name, Int size, Uint levels = 1) {
+        auto texture = MakeShared<TextureObject2D>(name);
+        texture->SetInternalFormat(TextureInternalFormat::RGBA8);
+        for (Uint level = 0; level < levels; ++level) {
+            const Int extent = std::max<Int>(size >> level, 1);
+            texture->AllocateStorage(TextureUploadTarget::Texture2D, level,
+                                     MipmapInput{IntVec3{extent, extent, 1},
+                                                 static_cast<SizeT>(extent) * static_cast<SizeT>(extent) * 4});
+        }
+        return texture;
+    }
+
+    void BindDrawAndRead(const SharedPtr<FramebufferObject>& draw, const SharedPtr<FramebufferObject>& read) {
+        Ctx().GetFramebufferBindingSlot(FramebufferTarget::Draw).Bind(draw);
+        Ctx().GetFramebufferBindingSlot(FramebufferTarget::Read).Bind(read);
+    }
+} // namespace
+
+// ============================ D-C1 / D-C2 ============================
+//
+// THE RESOLVED READ SURFACE IS WHAT STRUCTURALLY CLOSES THE read-buffer-shared-FBO DEFECT
+// CLASS. The record carries the surface itself rather than an index, and EVERY record resolves
+// it from the framebuffer ITS OWN Fbo names - Named included (c0e / MGPipeTypes.h). v1 resolved
+// a DRAW record's ReadSurface from the READ-bound object, which was D-C2's letter and muddled
+// in substance: no field of this record may refer to "whatever is bound", and a glReadBuffer on
+// the read FBO moved the draw record's ContentHash and forced a redundant draw emission.
+TEST(FramebufferEmit, EveryRecordsReadSurfaceComesFromItsOwnFramebuffersReadBuffer) {
+    FramebufferScope scope;
+    const auto drawColor = MakeColorTexture(1, 32);
+    const auto readColor0 = MakeColorTexture(2, 32);
+    const auto readColor1 = MakeColorTexture(3, 32);
+
+    const auto drawFbo = MakeShared<FramebufferObject>(1);
+    drawFbo->AttachTexture(FramebufferAttachmentType::Color0, drawColor, TextureUploadTarget::Texture2D);
+    const auto readFbo = MakeShared<FramebufferObject>(2);
+    readFbo->AttachTexture(FramebufferAttachmentType::Color0, readColor0, TextureUploadTarget::Texture2D);
+    readFbo->AttachTexture(FramebufferAttachmentType::Color1, readColor1, TextureUploadTarget::Texture2D);
+    readFbo->SetReadBuffer(FramebufferAttachmentType::Color1);
+    BindDrawAndRead(drawFbo, readFbo);
+
+    Framebuffers().EmitFramebufferState(Ctx());
+    EXPECT_EQ(Framebuffers().EmissionCount(), 2u) << "two distinct bindings are two records";
+
+    const MGPipeHandle readColor1Handle =
+        MGPipeSlots().FindByLifetimeId(MGPipeKind::Texture, readColor1->GetLifetimeId());
+    ASSERT_FALSE(MGPipeHandleIsNull(readColor1Handle));
+    const MGPipeHandle drawColorHandle =
+        MGPipeSlots().FindByLifetimeId(MGPipeKind::Texture, drawColor->GetLifetimeId());
+    ASSERT_FALSE(MGPipeHandleIsNull(drawColorHandle));
+    EXPECT_EQ(Framebuffers().LastDraw().Target, static_cast<Uint8>(MGPipeFramebufferTarget::Draw));
+    EXPECT_TRUE(Framebuffers().LastDraw().ReadSurface.Res == drawColorHandle)
+        << "the DRAW record's ReadSurface names a surface that is not part of the framebuffer its "
+           "own Fbo names";
+    EXPECT_EQ(Framebuffers().LastRead().Target, static_cast<Uint8>(MGPipeFramebufferTarget::Read));
+    EXPECT_TRUE(Framebuffers().LastRead().ReadSurface.Res == readColor1Handle)
+        << "MGPFramebufferState::ReadSurface on the READ record did not come from that "
+           "framebuffer's own read buffer";
+
+    // AND THE DRAW RECORD DOES NOT MOVE WHEN THE READ FRAMEBUFFER'S READ BUFFER DOES.
+    const Uint64 drawHashBefore = Framebuffers().LastDraw().ContentHash;
+    const Uint64 emissionsBefore = Framebuffers().EmissionCount();
+    readFbo->SetReadBuffer(FramebufferAttachmentType::Color0);
+    Framebuffers().EmitFramebufferState(Ctx());
+    EXPECT_EQ(Framebuffers().EmissionCount(), emissionsBefore + 1)
+        << "only the READ record moved, so exactly one record goes out";
+    EXPECT_EQ(Framebuffers().LastDraw().ContentHash, drawHashBefore)
+        << "a glReadBuffer on the read framebuffer moved the DRAW record's content hash";
+    // And the draw-buffer array belongs to the DRAW object, whichever record carries it.
+    EXPECT_EQ(Framebuffers().LastDraw().DrawBuffers[0], 0);
+}
+
+TEST(FramebufferEmit, OneObjectBoundToBothTargetsEmitsOneRecordWithTargetBoth) {
+    FramebufferScope scope;
+    const auto color0 = MakeColorTexture(4, 32);
+    const auto color1 = MakeColorTexture(5, 32);
+    const auto fbo = MakeShared<FramebufferObject>(3);
+    fbo->AttachTexture(FramebufferAttachmentType::Color0, color0, TextureUploadTarget::Texture2D);
+    fbo->AttachTexture(FramebufferAttachmentType::Color1, color1, TextureUploadTarget::Texture2D);
+    fbo->SetReadBuffer(FramebufferAttachmentType::Color1);
+    BindDrawAndRead(fbo, fbo);
+
+    Framebuffers().EmitFramebufferState(Ctx());
+    EXPECT_EQ(Framebuffers().EmissionCount(), 1u) << "one object on both targets is ONE record";
+    EXPECT_EQ(Framebuffers().LastDraw().Target, static_cast<Uint8>(MGPipeFramebufferTarget::Both));
+    const MGPipeHandle color1Handle =
+        MGPipeSlots().FindByLifetimeId(MGPipeKind::Texture, color1->GetLifetimeId());
+    EXPECT_TRUE(Framebuffers().LastDraw().ReadSurface.Res == color1Handle)
+        << "the shared-FBO record's ReadSurface is not that object's own read buffer";
+}
+
+// ============================ D-C4 ============================
+//
+// THE fragColor BROADCAST TRAP. The backend derives the broadcast count from the draw-buffer
+// array, at the verb, from the framebuffer state it then holds - precisely so a program can
+// relink inside the same draw. A hash that did not cover the array would let a suppressed
+// set_framebuffer_state mean "the draw buffers did not move" when they had, and the shader
+// would be specialised for the previous output shape.
+TEST(FramebufferEmit, ADrawBufferChangeAloneStillMovesTheContentHash) {
+    FramebufferScope scope;
+    const auto color0 = MakeColorTexture(6, 32);
+    const auto color1 = MakeColorTexture(7, 32);
+    const auto fbo = MakeShared<FramebufferObject>(4);
+    fbo->AttachTexture(FramebufferAttachmentType::Color0, color0, TextureUploadTarget::Texture2D);
+    fbo->AttachTexture(FramebufferAttachmentType::Color1, color1, TextureUploadTarget::Texture2D);
+    BindDrawAndRead(fbo, fbo);
+
+    Framebuffers().EmitFramebufferState(Ctx());
+    ASSERT_EQ(Framebuffers().EmissionCount(), 1u);
+    const Uint64 before = Framebuffers().LastDraw().ContentHash;
+    const Int8 slot1Before = Framebuffers().LastDraw().DrawBuffers[1];
+
+    // NOTHING BUT THE DRAW-BUFFER ARRAY MOVES: the same attachments, the same extent, the same
+    // completeness answer, the same handle.
+    fbo->SetDrawBuffer(1, FramebufferAttachmentType::Color1);
+    Framebuffers().EmitFramebufferState(Ctx());
+    EXPECT_EQ(Framebuffers().EmissionCount(), 2u)
+        << "a draw-buffer change alone was suppressed, which would freeze the fragColor "
+           "broadcast count at the previous output shape";
+    EXPECT_NE(Framebuffers().LastDraw().ContentHash, before)
+        << "MGPFramebufferState::ContentHash does not cover DrawBuffers[]";
+    EXPECT_NE(Framebuffers().LastDraw().DrawBuffers[1], slot1Before);
+    EXPECT_EQ(Framebuffers().LastDraw().DrawBuffers[1], 1);
+}
+
+TEST(FramebufferEmit, ARecycledFramebufferHandleIsNeverSuppressedAgainstItsPredecessor) {
+    FramebufferScope scope;
+    // The SAME attachment set on both objects, so every other field of the record is identical
+    // and Fbo is the only thing that can move the hash.
+    const auto color = MakeColorTexture(8, 32);
+    Uint64 firstHash = 0;
+    MGPipeHandle firstHandle{};
+    {
+        const auto first = MakeShared<FramebufferObject>(5);
+        first->AttachTexture(FramebufferAttachmentType::Color0, color, TextureUploadTarget::Texture2D);
+        BindDrawAndRead(first, first);
+        Framebuffers().EmitFramebufferState(Ctx());
+        ASSERT_EQ(Framebuffers().EmissionCount(), 1u);
+        firstHash = Framebuffers().LastDraw().ContentHash;
+        firstHandle = Framebuffers().LastDraw().Fbo;
+        BindDrawAndRead(nullptr, nullptr);
+    }
+    const auto second = MakeShared<FramebufferObject>(5);
+    second->AttachTexture(FramebufferAttachmentType::Color0, color, TextureUploadTarget::Texture2D);
+    BindDrawAndRead(second, second);
+    Framebuffers().EmitFramebufferState(Ctx());
+    const MGPFramebufferState& record = Framebuffers().LastDraw();
+    EXPECT_EQ(record.Fbo.Slot, firstHandle.Slot) << "the slot was not recycled; the case proves nothing";
+    EXPECT_NE(record.Fbo.Gen, firstHandle.Gen) << "a recycled slot must carry a new generation";
+    EXPECT_NE(record.ContentHash, firstHash)
+        << "MGPFramebufferState::ContentHash does not cover Fbo, so a recycled framebuffer handle "
+           "would be suppressed against its predecessor's record";
+}
+
+// ============================ G6 ============================
+//
+// "For every framebuffer configuration the emitted MGPFramebufferState reproduces exactly the
+// values the backend's SyncToBackend family reads from the frontend today, field by field."
+// The oracle is the frontend attachment itself, read back through the same getters the twin
+// uses, so this cannot drift into asserting what the emitter happens to do.
+TEST(FramebufferEmit, EveryAttachmentFieldSurvivesTheSurfaceConversion) {
+    FramebufferScope scope;
+    const auto fbo = MakeShared<FramebufferObject>(6);
+    Vector<SharedPtr<TextureObject2D>> colors;
+    for (SizeT i = 0; i < kMGPipeMaxColorAttachments; ++i) {
+        colors.push_back(MakeColorTexture(static_cast<Uint>(20 + i), 32, 2));
+        // Distinct level, layer and layered flag per point, so a conversion that dropped one
+        // field could not be masked by another point's value.
+        fbo->AttachTexture(static_cast<FramebufferAttachmentType>(
+                               static_cast<Int>(FramebufferAttachmentType::Color0) + static_cast<Int>(i)),
+                           colors.back(), TextureUploadTarget::Texture2D,
+                           static_cast<int>(i % 2), static_cast<int>(i), (i % 2) == 0);
+    }
+    const auto depth = MakeShared<RenderbufferObject>(2);
+    depth->SetInternalFormat(TextureInternalFormat::Depth24Stencil8);
+    depth->AllocateStorage(IntVec2{32, 32});
+    fbo->AttachRenderbuffer(FramebufferAttachmentType::Depth, depth);
+    const auto stencil = MakeColorTexture(40, 32);
+    fbo->AttachTexture(FramebufferAttachmentType::Stencil, stencil, TextureUploadTarget::Texture2D);
+    BindDrawAndRead(fbo, fbo);
+
+    Framebuffers().EmitFramebufferState(Ctx());
+    ASSERT_EQ(Framebuffers().EmissionCount(), 1u);
+    const MGPFramebufferState& record = Framebuffers().LastDraw();
+
+    for (SizeT i = 0; i < kMGPipeMaxColorAttachments; ++i) {
+        const auto type = static_cast<FramebufferAttachmentType>(
+            static_cast<Int>(FramebufferAttachmentType::Color0) + static_cast<Int>(i));
+        const auto& attachment = fbo->GetAttachment(type);
+        const MGPSurface& surface = record.Color[i];
+        const MGPipeHandle expected =
+            MGPipeSlots().FindByLifetimeId(MGPipeKind::Texture, attachment.GetTexture()->GetLifetimeId());
+        EXPECT_TRUE(surface.Res == expected) << "MGPSurface::Res at colour point " << i;
+        EXPECT_EQ(surface.Kind, kMGPipeSurfaceKindTexture) << "MGPSurface::Kind at colour point " << i;
+        EXPECT_EQ(surface.InternalFormat, static_cast<Uint32>(attachment.GetTexture()->GetFormat()))
+            << "MGPSurface::InternalFormat at colour point " << i;
+        EXPECT_EQ(surface.Level, static_cast<Uint16>(attachment.GetTextureLevel()))
+            << "MGPSurface::Level at colour point " << i;
+        EXPECT_EQ(surface.Layer, static_cast<Uint32>(attachment.GetTextureLayer()))
+            << "MGPSurface::Layer at colour point " << i;
+        EXPECT_EQ(surface.Layered, attachment.IsLayered() ? 1 : 0)
+            << "MGPSurface::Layered at colour point " << i;
+        EXPECT_EQ(surface.UploadTarget, static_cast<Uint16>(TextureUploadTarget::Texture2D))
+            << "MGPSurface::UploadTarget at colour point " << i;
+        // ID-12 DV-5: three of the four cross-object masks reduce to (format, TEXTURE TARGET)
+        // and no TextureUploadTarget -> TextureTarget inverse exists anywhere in the tree.
+        EXPECT_EQ(surface.TextureTarget,
+                  static_cast<Uint16>(attachment.GetTexture()->GetTarget()))
+            << "MGPSurface::TextureTarget at colour point " << i;
+    }
+
+    EXPECT_EQ(record.Depth.Kind, kMGPipeSurfaceKindRenderbuffer) << "MGPSurface::Kind on the depth point";
+    EXPECT_EQ(record.Depth.InternalFormat, static_cast<Uint32>(depth->GetInternalFormat()))
+        << "MGPSurface::InternalFormat on the depth point";
+    EXPECT_TRUE(record.Depth.Res ==
+                MGPipeSlots().FindByLifetimeId(MGPipeKind::Renderbuffer, depth->GetLifetimeId()))
+        << "MGPSurface::Res on the depth point";
+    EXPECT_EQ(record.Depth.Layered, 0) << "MGPSurface::Layered on the depth point";
+    EXPECT_EQ(record.Depth.TextureTarget, kMGPipeSurfaceNoTextureTarget)
+        << "MGPSurface::TextureTarget on the RENDERBUFFER point must be the Unknown sentinel";
+    EXPECT_EQ(record.Stencil.Kind, kMGPipeSurfaceKindTexture) << "MGPSurface::Kind on the stencil point";
+    EXPECT_TRUE(record.Stencil.Res ==
+                MGPipeSlots().FindByLifetimeId(MGPipeKind::Texture, stencil->GetLifetimeId()))
+        << "MGPSurface::Res on the stencil point";
+
+    EXPECT_EQ(record.Width, 32u) << "MGPFramebufferState::Width";
+    EXPECT_EQ(record.Height, 32u) << "MGPFramebufferState::Height";
+    EXPECT_EQ(record.IsDefault, 0) << "MGPFramebufferState::IsDefault";
+    // Complete is FramebufferObject::CheckCompleteness(), the FRONTEND-only answer, and never
+    // glCheckFramebufferStatus's - that entry point additionally consults the backend's probed
+    // format-capability cache, which a client emitting it would be reading from the wrong side.
+    EXPECT_EQ(record.Complete, fbo->CheckCompleteness() ? 1 : 0) << "MGPFramebufferState::Complete";
+    // And an empty point really is {null, None} and every other field zero.
+    const auto emptyFbo = MakeShared<FramebufferObject>(7);
+    emptyFbo->AttachTexture(FramebufferAttachmentType::Color0, colors[0], TextureUploadTarget::Texture2D);
+    BindDrawAndRead(emptyFbo, emptyFbo);
+    Framebuffers().EmitFramebufferState(Ctx());
+    EXPECT_TRUE(MGPipeHandleIsNull(Framebuffers().LastDraw().Color[1].Res));
+    EXPECT_EQ(Framebuffers().LastDraw().Color[1].Kind, kMGPipeSurfaceKindNone);
+    EXPECT_EQ(Framebuffers().LastDraw().Color[1].InternalFormat, 0u);
+    // BOTH TARGET FIELDS CARRY THE SENTINEL, not 0 (m6 / ID-12 DV-5): a Uint16 zero is
+    // TextureUploadTarget::Texture1D and TextureTarget::Texture1D, so a reader that forgot to
+    // gate on Kind would read a plausible wrong answer instead of a nonsense one.
+    EXPECT_EQ(Framebuffers().LastDraw().Color[1].UploadTarget,
+              static_cast<Uint16>(TextureUploadTarget::Unknown));
+    EXPECT_EQ(Framebuffers().LastDraw().Color[1].TextureTarget, kMGPipeSurfaceNoTextureTarget);
+}
+
+// ============================ D-C3 ============================
+TEST(FramebufferEmit, AnAttachmentPointAboveTheWireWidthIsRefusedNotTruncated) {
+    FramebufferScope scope;
+    const auto color = MakeColorTexture(50, 32);
+    const auto beyond = MakeColorTexture(51, 32);
+    const auto fbo = MakeShared<FramebufferObject>(8);
+    fbo->AttachTexture(FramebufferAttachmentType::Color0, color, TextureUploadTarget::Texture2D);
+    BindDrawAndRead(fbo, fbo);
+    Framebuffers().EmitFramebufferState(Ctx());
+    ASSERT_EQ(Framebuffers().EmissionCount(), 1u);
+    ASSERT_EQ(Framebuffers().RefusedCount(), 0u);
+
+    // MGPFramebufferState::Color[] is eight wide and MaxColorAttachments is the driver's raw ES
+    // cap, not clamped to eight on the GLES path. Truncating silently is the bug class this
+    // phase is closing, so the record is REFUSED and the legacy arm runs.
+    fbo->AttachTexture(static_cast<FramebufferAttachmentType>(
+                           static_cast<Int>(FramebufferAttachmentType::Color0) +
+                           static_cast<Int>(kMGPipeMaxColorAttachments)),
+                       beyond, TextureUploadTarget::Texture2D);
+    Framebuffers().EmitFramebufferState(Ctx());
+    EXPECT_EQ(Framebuffers().EmissionCount(), 1u)
+        << "an attachment above the wire width was truncated into a record instead of refused";
+    EXPECT_GE(Framebuffers().RefusedCount(), 1u) << "the refusal was not counted";
+}
+
+// ============================ D-D2 ============================
+//
+// RED BEFORE THIS PACKAGE LANDED. RenderbufferObject's three storage setters bump no version
+// and raise no notice, and the framebuffer bit's shutter does not move when an ALREADY-ATTACHED
+// renderbuffer is re-storaged - so `glBindRenderbuffer; glRenderbufferStorage(newSize)` on an
+// attached renderbuffer published nothing at all.
+TEST(FramebufferEmit, ARestoragedAttachedRenderbufferPublishesItsNewExtent) {
+    FramebufferScope scope;
+    const auto renderbuffer = MakeShared<RenderbufferObject>(3);
+    renderbuffer->SetInternalFormat(TextureInternalFormat::Depth24Stencil8);
+    renderbuffer->AllocateStorage(IntVec2{64, 64});
+    const auto fbo = MakeShared<FramebufferObject>(9);
+    fbo->AttachRenderbuffer(FramebufferAttachmentType::Depth, renderbuffer);
+    BindDrawAndRead(fbo, fbo);
+    Framebuffers().EmitFramebufferState(Ctx());
+
+    const MGPipeHandle handle =
+        MGPipeSlots().FindByLifetimeId(MGPipeKind::Renderbuffer, renderbuffer->GetLifetimeId());
+    ASSERT_FALSE(MGPipeHandleIsNull(handle));
+    const Uint64 respecifiesBefore = MGPipeTextureEmitterInstance().RespecifyCount();
+
+    // NO BIND, NO ATTACHMENT CHANGE, NO DIRTY BIT - only the storage entry point.
+    renderbuffer->AllocateStorage(IntVec2{128, 96});
+    EXPECT_GT(MGPipeTextureEmitterInstance().RespecifyCount(), respecifiesBefore)
+        << "a re-storaged attached renderbuffer published nothing";
+    const MGPResourceDesc desc = MGPipeTextureEmitterInstance().LastDesc();
+    EXPECT_TRUE(desc.Resource == handle);
+    EXPECT_EQ(desc.Width, 128u);
+    EXPECT_EQ(desc.Height, 96u);
+}
+
+TEST(FramebufferEmit, AnUnchangedBindingPairEmitsNothing) {
+    FramebufferScope scope;
+    const auto color = MakeColorTexture(60, 32);
+    const auto fbo = MakeShared<FramebufferObject>(10);
+    fbo->AttachTexture(FramebufferAttachmentType::Color0, color, TextureUploadTarget::Texture2D);
+    BindDrawAndRead(fbo, fbo);
+    const Uint64 bytes = Framebuffers().EmitFramebufferState(Ctx());
+    EXPECT_EQ(bytes, sizeof(MGPFramebufferState));
+    EXPECT_EQ(Framebuffers().EmissionCount(), 1u);
+    // The version-first skip: nothing moved, so nothing goes out and nothing is hashed twice.
+    EXPECT_EQ(Framebuffers().EmitFramebufferState(Ctx()), 0u);
+    EXPECT_EQ(Framebuffers().EmissionCount(), 1u);
+}
+
+// ============================ ID-19(c) ============================
+//
+// THE HOLE esprytobj's C-1 FOUND. The applier keeps framebuffer records PER OBJECT, but v1 only
+// ever built the two BOUND-target records at the validate point - so glClearNamedFramebufferfv
+// on an fbo bound to NEITHER binding reached a backend that minted a driver framebuffer with no
+// attachments, found no record for it, declined, and cleared against it anyway.
+TEST(FramebufferEmit, AFramebufferHandedOverByNameGetsANamedRecordWithoutMovingABinding) {
+    FramebufferScope scope;
+    const auto boundColor = MakeColorTexture(70, 32);
+    const auto namedColor = MakeColorTexture(71, 16);
+    const auto bound = MakeShared<FramebufferObject>(20);
+    bound->AttachTexture(FramebufferAttachmentType::Color0, boundColor, TextureUploadTarget::Texture2D);
+    BindDrawAndRead(bound, bound);
+    Framebuffers().EmitFramebufferState(Ctx());
+    ASSERT_NE(MGPipeApplier().DrawFramebuffer(), nullptr);
+    const MGPipeHandle boundHandle = MGPipeApplier().DrawFramebuffer()->Fbo;
+    const Uint64 serialBefore = MGPipeApplier().FramebufferSerial;
+
+    // The object the DSA entry point is about to hand over, bound to neither binding.
+    const auto named = MakeShared<FramebufferObject>(21);
+    named->AttachTexture(FramebufferAttachmentType::Color0, namedColor, TextureUploadTarget::Texture2D);
+    const Uint64 bytes = Framebuffers().EmitFramebufferByName(*named);
+    EXPECT_EQ(bytes, sizeof(MGPFramebufferState));
+    EXPECT_EQ(Framebuffers().LastNamed().Target, static_cast<Uint8>(MGPipeFramebufferTarget::Named));
+    EXPECT_GT(MGPipeApplier().FramebufferSerial, serialBefore) << "a Named record must publish";
+
+    const MGPFramebufferState* stored =
+        MGPipeApplier().FramebufferRecordFor(Framebuffers().LastNamed().Fbo);
+    ASSERT_NE(stored, nullptr) << "the framebuffer the server is about to receive by name has no record";
+    EXPECT_EQ(stored->Width, 16u) << "the Named record does not describe the object it names";
+
+    // AND IT MOVED NEITHER BINDING.
+    ASSERT_NE(MGPipeApplier().DrawFramebuffer(), nullptr);
+    EXPECT_TRUE(MGPipeApplier().DrawFramebuffer()->Fbo == boundHandle)
+        << "a Named record took the draw binding";
+    ASSERT_NE(MGPipeApplier().ReadFramebuffer(), nullptr);
+    EXPECT_TRUE(MGPipeApplier().ReadFramebuffer()->Fbo == boundHandle)
+        << "a Named record took the read binding";
+}
+
+TEST(FramebufferEmit, ANamedRecordIsSuppressedPerObjectAndNeverAgainstABoundRecord) {
+    FramebufferScope scope;
+    const auto colorA = MakeColorTexture(72, 32);
+    const auto colorB = MakeColorTexture(73, 32);
+    const auto first = MakeShared<FramebufferObject>(22);
+    first->AttachTexture(FramebufferAttachmentType::Color0, colorA, TextureUploadTarget::Texture2D);
+    const auto second = MakeShared<FramebufferObject>(23);
+    second->AttachTexture(FramebufferAttachmentType::Color0, colorB, TextureUploadTarget::Texture2D);
+
+    // TWO DIFFERENT OBJECTS' Named RECORDS IN A ROW MUST BOTH GO OUT: the suppressor is keyed by
+    // the framebuffer the record names and never by one global slot.
+    EXPECT_GT(Framebuffers().EmitFramebufferByName(*first), 0u);
+    EXPECT_GT(Framebuffers().EmitFramebufferByName(*second), 0u);
+    EXPECT_EQ(Framebuffers().EmissionCount(), 2u);
+    // A repeat of the same object with nothing moved costs nothing.
+    EXPECT_EQ(Framebuffers().EmitFramebufferByName(*second), 0u);
+    EXPECT_EQ(Framebuffers().EmissionCount(), 2u);
+    // ...and the first object's record is still its own, not the second's.
+    EXPECT_EQ(Framebuffers().EmitFramebufferByName(*first), 0u);
+
+    // A BOUND OBJECT IS NEVER HANDED A Named RECORD, because the record would then say "no
+    // binding" while BoundFramebuffer still resolves through it.
+    BindDrawAndRead(first, nullptr);
+    Framebuffers().EmitFramebufferByName(*first);
+    ASSERT_NE(MGPipeApplier().DrawFramebuffer(), nullptr);
+    EXPECT_EQ(MGPipeApplier().DrawFramebuffer()->Target, static_cast<Uint8>(MGPipeFramebufferTarget::Draw))
+        << "a by-name publish of a DRAW-bound framebuffer overwrote its record with Target = Named";
+}
+
+// ============================ m2 ============================
+TEST(FramebufferEmit, ADrawBufferTokenAboveTheWireWidthIsRefusedNotTruncated) {
+    FramebufferScope scope;
+    const auto color = MakeColorTexture(74, 32);
+    const auto fbo = MakeShared<FramebufferObject>(24);
+    fbo->AttachTexture(FramebufferAttachmentType::Color0, color, TextureUploadTarget::Texture2D);
+    BindDrawAndRead(fbo, fbo);
+    Framebuffers().EmitFramebufferState(Ctx());
+    ASSERT_EQ(Framebuffers().EmissionCount(), 1u);
+    ASSERT_EQ(Framebuffers().RefusedCount(), 0u);
+
+    // A LEGAL STATE THE ATTACHMENT SCAN CANNOT SEE: nothing is attached at the point the token
+    // names, so D-C3's attachment loop passes, and MGPipeDrawBufferIndex would write an index of
+    // 8 or more into an 8-wide array.
+    fbo->SetDrawBuffer(0, static_cast<FramebufferAttachmentType>(
+                              static_cast<Int>(FramebufferAttachmentType::Color0) +
+                              static_cast<Int>(kMGPipeMaxColorAttachments) + 2));
+    Framebuffers().EmitFramebufferState(Ctx());
+    EXPECT_EQ(Framebuffers().EmissionCount(), 1u)
+        << "a draw-buffer token naming a colour point at or above the wire width was truncated "
+           "into a record instead of refused";
+    EXPECT_GE(Framebuffers().RefusedCount(), 1u) << "the refusal was not counted";
+}
+
+// ============================ m1 ============================
+TEST(FramebufferEmit, ALayeredCubeAttachmentDoesNotAssertAFaceItCannotKnow) {
+    FramebufferScope scope;
+    const auto cube = MakeShared<TextureObject2DCube>(75);
+    cube->SetInternalFormat(TextureInternalFormat::RGBA8);
+    for (const TextureUploadTarget face : cube->GetUploadTargets()) {
+        cube->AllocateStorage(face, 0, MipmapInput{IntVec3{16, 16, 1}, 16 * 16 * 4});
+    }
+    ASSERT_GT(cube->GetUploadTargets().size(), 1u);
+
+    const auto fbo = MakeShared<FramebufferObject>(25);
+    // The LAYERED entry point carries no face token, so the attachment stores Unknown. v1 fell
+    // back to GetUploadTargets()[0] - which is CubeMapPositiveX - and the record then ASSERTED a
+    // face that is not the truth for an attachment naming all six. The precedent it copied
+    // (FramebufferAttachmentObject::GetSize) only needs an EXTENT, which is identical across the
+    // six faces; face identity is not.
+    fbo->AttachTexture(FramebufferAttachmentType::Color0, cube, TextureUploadTarget::Unknown, 0, 0, true);
+    BindDrawAndRead(fbo, fbo);
+    Framebuffers().EmitFramebufferState(Ctx());
+    ASSERT_EQ(Framebuffers().EmissionCount(), 1u);
+    EXPECT_EQ(Framebuffers().LastDraw().Color[0].Layered, 1);
+    EXPECT_EQ(Framebuffers().LastDraw().Color[0].UploadTarget,
+              static_cast<Uint16>(TextureUploadTarget::Unknown))
+        << "a layered cube attachment resolved to one face, so the record asserts a face the "
+           "attachment does not name";
+    EXPECT_EQ(Framebuffers().LastDraw().Color[0].TextureTarget,
+              static_cast<Uint16>(TextureTarget::TextureCubeMap))
+        << "MGPSurface::TextureTarget is what a cross-object mask reads instead";
+}
+
+TEST(FramebufferEmit, EveryNonTexturePointCarriesTheUnknownSentinelsRatherThanZero) {
+    FramebufferScope scope;
+    const auto color = MakeColorTexture(76, 32);
+    const auto depth = MakeShared<RenderbufferObject>(4);
+    depth->SetInternalFormat(TextureInternalFormat::Depth24Stencil8);
+    depth->AllocateStorage(IntVec2{32, 32});
+    const auto fbo = MakeShared<FramebufferObject>(26);
+    fbo->AttachTexture(FramebufferAttachmentType::Color0, color, TextureUploadTarget::Texture2D);
+    fbo->AttachRenderbuffer(FramebufferAttachmentType::Depth, depth);
+    BindDrawAndRead(fbo, fbo);
+    Framebuffers().EmitFramebufferState(Ctx());
+    const MGPFramebufferState& record = Framebuffers().LastDraw();
+
+    // The RENDERBUFFER point, the EMPTY colour points and the STENCIL point that names nothing.
+    for (const MGPSurface* surface : {&record.Depth, &record.Stencil, &record.Color[1]}) {
+        EXPECT_NE(surface->Kind, kMGPipeSurfaceKindTexture);
+        EXPECT_EQ(surface->UploadTarget, static_cast<Uint16>(TextureUploadTarget::Unknown))
+            << "a non-texture point says TextureUploadTarget::Texture1D, which is what 0 means";
+        EXPECT_EQ(surface->TextureTarget, kMGPipeSurfaceNoTextureTarget)
+            << "a non-texture point says TextureTarget::Texture1D, which is what 0 means";
+    }
+    // And the texture point is unaffected.
+    EXPECT_EQ(record.Color[0].TextureTarget, static_cast<Uint16>(TextureTarget::Texture2D));
+
+    // THE FIELD IS IN THE HASH, so a texture-target change alone cannot be suppressed.
+    MGPSurface probe = record.Color[0];
+    MGPFramebufferState probeState = record;
+    probeState.Color[0].TextureTarget = static_cast<Uint16>(TextureTarget::TextureRectangle);
+    EXPECT_NE(MGPipeFramebufferStateContentHash(probeState), MGPipeFramebufferStateContentHash(record))
+        << "MGPipeCopySurfaceForHash does not copy MGPSurface::TextureTarget, so a record whose "
+           "only moved field is the attachment's texture target would be suppressed";
+    (void)probe;
+}
+#endif // MOBILEGL_PIPE_PUSH
+
 // =========================================================================================
 // The APPLIER's half of set_framebuffer_state (the wire commits'). The emitter's half - the
 // resolved read surface, the draw-buffer array in the content hash, a recycled handle never
@@ -575,6 +1147,20 @@ int main(int argc, char** argv) {
     _putenv_s("MOBILEGL_LOG_FILE_PATH", g_logPath.c_str());
 #else
     setenv("MOBILEGL_LOG_FILE_PATH", g_logPath.c_str(), 1);
+#endif
+#if MOBILEGL_PIPE_PUSH
+    // ID-39: A BACKEND IS PRESENT, for the whole binary. Since ID-39 every P4a-family entry
+    // point in MG_Pipe/PipeApply.cpp declines a record - and the client's gate in
+    // MG_Impl/Pipe/PipeFill.cpp emits none at all - when no backend has registered
+    // MGPipeResourceOps, because acceptance is a contract with the emitter and an accepted
+    // record nothing reads makes the client clear work the legacy pull path still owed. Every
+    // case in this suite is about the arm where a backend DOES consume the records, which is
+    // the shipped DirectGLES configuration, so it installs the same signal that backend
+    // installs. The table is empty because none of its hooks is on a framebuffer path at all:
+    // set_framebuffer_state stores a record and dispatches nothing. The two arms of the rule
+    // itself are pinned in ResourceEmitTest and TextureEmitTest.
+    static const MGPipeResourceOps kConsumerPresent{};
+    MGPipeSetResourceOps(&kConsumerPresent);
 #endif
     ::testing::InitGoogleTest(&argc, argv);
     const int rc = RUN_ALL_TESTS();

MobileGL/MG_Test/Pipe/ImageEmitTest.cpp

@@ -6,20 +6,16 @@
 // SPDX-License-Identifier: LGPL-3.0-only
 // End of Source File Header
 
-// P4a's image-unit set: set_shader_images, the third of the three kVarTail unit sets. It rides
-// the sampler family's subsystem bit - one family, one A/B - and has its own suite because its
-// content hash has to cover two fields the other two sets do not carry.
+// P4a's third kVarTail unit set, set_shader_images. It rides the sampler family's subsystem
+// bit: one family, one A/B.
 //
-// THE TWO CASES THIS SUITE EXISTS FOR: an ACCESS-mode change alone, and an INTERNAL-FORMAT
-// change alone, each has to move the hash and emit the set. Both are live glBindImageTexture
-// state, the format-less image bake keys on the format the shader was built against, and a
-// hash over the bindings alone would suppress exactly the record that says the bake is stale.
-// The behavioural gates beside them are the format-less bake and non-core-format scenarios,
-// and the photon fixture on desktop retrace - the only fixture that has ever caught an
-// image-binding-semantics regression, and one that must never be run on the Adreno.
+// WHAT THIS SUITE IS FOR. The image set is the one whose ContentHash has to cover more than
+// the binding: InternalFormat and Access are live glBindImageTexture state that the
+// format-less image bake keys on, so a set whose only movement is an access mode still has to
+// go out. And the zero early-out is the property an optimisation deletes by accident - it is
+// what makes every draw of every application that never binds an image pay one integer test.
 //
-// THE SUITE IS `ImageEmit`, not `ImageEmitTest`: the file is XTest.cpp and the suite is X,
-// this directory's convention, and it is what the gates grep for.
+// THE SUITE IS `ImageEmit`, not `ImageEmitTest`: the file is XTest.cpp and the suite is X.
 //
 // THE TARGET AND ITS ctest REGISTRATION ARE THE CONTRACT COMMIT'S; THE CONTENTS ARE NOT.
 //
@@ -48,8 +44,14 @@
 #include "Includes.h"
 #include <MG_Pipe/MGPipe.h>
 #if MOBILEGL_PIPE_PUSH
+#include "Init.h"
+#include <MG_Impl/GLImpl/Program/GL_Program.h>
+#include <MG_Impl/GLImpl/Texture/GL_Texture.h>
 #include <MG_Impl/Pipe/ImageEmit.h>
+#include <MG_Impl/Pipe/SetHashSuppressor.h>
+#include <MG_Impl/Pipe/SlotAllocator.h>
 #include <MG_Pipe/PipeApply.h>
+#include <MG_State/GLState/Core.h>
 #endif
 
 using namespace MobileGL;
@@ -67,13 +69,24 @@ namespace {
     }
 
 #if MOBILEGL_PIPE_PUSH
-    std::string ReadLog() {
+    // `from` is a byte offset, and it exists because of the fork below: the library's log file
+    // is already open by the time a case runs, so the child's lines are APPENDED to it rather
+    // than written to a fresh file, and only what the child appended is this drive's evidence.
+    std::string ReadLog(std::streamoff from = 0) {
         std::ifstream in(g_logPath, std::ios::binary);
+        if (from > 0) in.seekg(from, std::ios::beg);
         std::ostringstream ss;
         ss << in.rdbuf();
         return ss.str();
     }
 
+    // Where the library's log file currently ends. Reading from here after the child has
+    // aborted gives exactly the lines that drive produced.
+    std::streamoff LogEnd() {
+        std::ifstream in(g_logPath, std::ios::binary | std::ios::ate);
+        return in ? static_cast<std::streamoff>(in.tellg()) : std::streamoff{0};
+    }
+
     // A fresh applier per case, BOTH SCOPES, and it takes both because there are two: a reset
     // is a make-current and deliberately KEEPS the object records, so a fixture that wants a
     // genuinely empty applier has to say the other one as well. Every case is its own process
@@ -99,8 +112,14 @@ namespace {
     template <class Body>
     ChildResult RunInChild(Body body) {
         ChildResult result;
-        std::error_code ec;
-        std::filesystem::remove(g_logPath, ec);
+        // THE LOG PATH IS NOT UNLINKED HERE, and that is what this helper had to learn when the
+        // client's cases landed in the same file as the applier's: main() calls
+        // MobileGL::Initialize(), so the library's log FILE* is already open on this path and
+        // fork() duplicates it. Removing the path would leave the child writing into a deleted
+        // inode and the parent reading an empty file - the child would still abort, and the
+        // assertion on WHAT it named could never see the line. So the log's end is remembered
+        // and only what the child appended is read back.
+        const std::streamoff before = LogEnd();
         std::fflush(nullptr);
         const pid_t pid = ::fork();
         if (pid < 0) return result;
@@ -111,7 +130,7 @@ namespace {
         int status = 0;
         if (::waitpid(pid, &status, 0) != pid) return result;
         result.Status = status;
-        result.Log = ReadLog();
+        result.Log = ReadLog(before);
         return result;
     }
 
@@ -157,10 +176,9 @@ namespace {
 TEST(ImageEmit, TheEmitterIsOneNeverDestroyedProcessSingleton) {
 #if MOBILEGL_PIPE_PUSH
     EXPECT_EQ(&MGPipeImageEmitterInstance(), &MGPipeImageEmitterInstance());
-    // The image set's window is bounded by the same merged unit space the other two sets use;
-    // there is no separate image-unit capacity and there must not be one, because a record
-    // whose window is checked against a different bound from the array it indexes is the shape
-    // the applier's Fatal{ProtocolCorruption} exists to make impossible.
+    // The image set has no bit of its own: set_shader_images rides the SAMPLER subsystem,
+    // because the three unit sets are one family and an operator switching them off has to get
+    // the whole family's legacy arm.
     EXPECT_EQ(kMGPipeMaxImageUnits, kMGPipeMaxTextureUnits);
 #else
     GTEST_SKIP() << "MOBILEGL_PIPE_PUSH is off: there is no client emitter in a pull build";
@@ -323,6 +341,184 @@ TEST(ImageEmit, AMakeCurrentClearsTheImageSetAndAdvancesItsSerial) {
 #endif
 }
 
+#if !MOBILEGL_PIPE_PUSH
+// G2 requires the pull and push ctest name sets to be identical, name for name.
+#define MGL_IMAGE_EMIT_TEST_LIST(X)                                                                \
+    X(ImageEmit, AZeroHighWaterMarkEmitsNothingWithoutHashing)                                      \
+    X(ImageEmit, AnAccessModeChangeAloneStillEmitsTheSet)                                           \
+    X(ImageEmit, AnInternalFormatChangeAloneStillEmitsTheSet)                                       \
+    X(ImageEmit, TheApplicationsFormatAndAccessTravelUnrecast)
+
+#define MGL_DECLARE_PULL_SKIP(Suite, Name)                                                         \
+    TEST(Suite, Name) { GTEST_SKIP() << "compiled only under MOBILEGL_PIPE_PUSH"; }
+MGL_IMAGE_EMIT_TEST_LIST(MGL_DECLARE_PULL_SKIP)
+#undef MGL_DECLARE_PULL_SKIP
+#else
+
+namespace {
+    namespace GL = MobileGL::MG_Impl::GLImpl;
+    using GLContext = MG_State::GLState::GLContext;
+
+    struct EmitterScope {
+        EmitterScope() { Clear(); }
+        ~EmitterScope() { Clear(); }
+        EmitterScope(const EmitterScope&) = delete;
+        EmitterScope& operator=(const EmitterScope&) = delete;
+
+        static void Clear() {
+            MGPipeImageEmitterInstance().Reset();
+            MGPipeImageEmitterInstance().ResetCounters();
+            MGPipeProgramOpaqueUnitsShared().Invalidate();
+            MGPipeSetHashSuppressorInstance().InvalidateAll();
+        }
+    };
+
+    GLContext& Ctx() { return *MG_State::pGLContext; }
+    MGPipeImageEmitter& Emitter() { return MGPipeImageEmitterInstance(); }
+
+    GLuint MakeComputeProgram(const char* source) {
+        const GLuint shader = GL::CreateShader(GL_COMPUTE_SHADER);
+        GL::ShaderSource(shader, 1, &source, nullptr);
+        GL::CompileShader(shader);
+        const GLuint program = GL::CreateProgram();
+        GL::AttachShader(program, shader);
+        GL::LinkProgram(program);
+        GLint linked = GL_FALSE;
+        GL::GetProgramiv(program, GL_LINK_STATUS, &linked);
+        EXPECT_EQ(linked, GL_TRUE) << "the compute program did not link";
+        return program;
+    }
+
+    GLuint MakeImageTexture() {
+        GLuint name = 0;
+        GL::GenTextures(1, &name);
+        GL::BindTexture(GL_TEXTURE_2D, name);
+        GL::TexStorage2D(GL_TEXTURE_2D, 1, GL_RGBA8, 4, 4);
+        return name;
+    }
+
+    // PROPERTY 1 OF D-G4, and it is the one an optimisation deletes: an application that never
+    // binds an image pays one integer test per draw, taken BEFORE any hash and before any
+    // 192-entry walk.
+    //
+    // The frontend has no image-unit high-water mark of its own - NoteUnitTouched is the
+    // TEXTURE-unit path and glBindImageTexture does not reach it - so the window is derived
+    // from the highest image unit the CURRENT PROGRAM names. A program with no image uniform
+    // names none, and the set is not emitted at all.
+    TEST(ImageEmit, AZeroHighWaterMarkEmitsNothingWithoutHashing) {
+        EmitterScope scope;
+        static const char* kNoImages = R"(#version 430 core
+layout(local_size_x = 1) in;
+layout(std430, binding = 0) buffer Out { uint value; } outBuf;
+void main() { outBuf.value = 1u; }
+)";
+        const GLuint program = MakeComputeProgram(kNoImages);
+        GL::UseProgram(program);
+
+        // A texture IS bound to an image unit. The set still does not go out, because no
+        // shader can read it - which is the whole point of deriving the window from the
+        // program rather than walking 192 units to find out.
+        const GLuint texture = MakeImageTexture();
+        GL::BindImageTexture(0, texture, 0, GL_FALSE, 0, GL_READ_ONLY, GL_RGBA8);
+
+        EXPECT_EQ(Emitter().EmitShaderImages(Ctx()), 0u);
+        EXPECT_EQ(Emitter().ImageSetCount(), 0u);
+        EXPECT_EQ(Emitter().Window(), 0u);
+        GL::UseProgram(0);
+    }
+
+    const char* kImageCompute = R"(#version 430 core
+layout(local_size_x = 1) in;
+layout(binding = 1, rgba8) uniform image2D img;
+void main() { imageStore(img, ivec2(0), vec4(1.0)); }
+)";
+
+    // The record carries the APPLICATION's format and access verbatim. The bind-format recast -
+    // a GL_RG32F bind is INVALID_VALUE on most non-core formats on Adreno - and the
+    // buffer-texture split view are SERVER-side and stay there, so a client that pre-applied
+    // either of them would be answering a driver question from the wrong side of the boundary.
+    TEST(ImageEmit, TheApplicationsFormatAndAccessTravelUnrecast) {
+        EmitterScope scope;
+        const GLuint program = MakeComputeProgram(kImageCompute);
+        GL::UseProgram(program);
+        const GLuint texture = MakeImageTexture();
+        GL::BindImageTexture(1, texture, 0, GL_FALSE, 0, GL_WRITE_ONLY, GL_RGBA8);
+
+        // THE FIXTURE HAS TO SET UP WHAT THE CASE IS ABOUT, and it is asserted rather than
+        // assumed: the window comes from the program's own image uniforms, so a shader whose
+        // image uniform did not reach the reflection would make every case below pass for the
+        // wrong reason - by emitting nothing at all.
+        const SharedPtr<MG_State::GLState::ProgramObject>& object = Ctx().GetProgramObject(program);
+        ASSERT_TRUE(object);
+        const auto& resolution = MGPipeProgramOpaqueUnitsShared().For(object.get());
+        ASSERT_EQ(resolution.MaxImageUnit, 1)
+            << "maxUniformLocation=" << object->GetMaxUniformLocation()
+            << " unit@0=" << object->GetUniformSamplerOrImageUnitIndex(0)
+            << " linked=" << object->GetLinkStatus();
+
+        // ASSERTED ON THE COUNTER, NOT ON THIS CALL'S RETURN VALUE, and the reason is worth
+        // writing down because it surprised this suite: the glBindImageTexture above ALREADY
+        // reached the validate point and emitted the set, so a direct call afterwards is
+        // correctly suppressed as unchanged. What the case is about is what went out, not who
+        // sent it.
+        Emitter().EmitShaderImages(Ctx());
+        ASSERT_GE(Emitter().ImageSetCount(), 1u);
+        ASSERT_GE(Emitter().LastShaderImages().Count, 2u);
+        const MGPImageView& view = Emitter().LastImageViews()[1];
+        EXPECT_EQ(view.Unit, 1u);
+        EXPECT_FALSE(MGPipeHandleIsNull(view.Res));
+        EXPECT_EQ(view.InternalFormat, static_cast<Uint32>(GL_RGBA8));
+        EXPECT_EQ(view.Access, 1u) << "GL_WRITE_ONLY, folded into the one byte the wire carries";
+        EXPECT_EQ(view.Level, 0u);
+        EXPECT_EQ(view.Layered, 0u);
+        EXPECT_EQ(view.Layer, 0u);
+        GL::UseProgram(0);
+    }
+
+    TEST(ImageEmit, AnAccessModeChangeAloneStillEmitsTheSet) {
+        EmitterScope scope;
+        const GLuint program = MakeComputeProgram(kImageCompute);
+        GL::UseProgram(program);
+        const GLuint texture = MakeImageTexture();
+        GL::BindImageTexture(1, texture, 0, GL_FALSE, 0, GL_READ_ONLY, GL_RGBA8);
+        Emitter().EmitShaderImages(Ctx());
+        const Uint64 before = Emitter().ImageSetCount();
+        ASSERT_GE(before, 1u);
+        ASSERT_EQ(Emitter().LastImageViews()[1].Access, 0u) << "GL_READ_ONLY";
+
+        // The same texture, the same unit, the same format - only the access mode moves. The
+        // hash has to cover it, or a shader that now writes where it used to read is bound with
+        // the previous barrier and coherence semantics.
+        GL::BindImageTexture(1, texture, 0, GL_FALSE, 0, GL_READ_WRITE, GL_RGBA8);
+        Emitter().EmitShaderImages(Ctx());
+        EXPECT_GT(Emitter().ImageSetCount(), before);
+        EXPECT_EQ(Emitter().LastImageViews()[1].Access, 2u);
+        GL::UseProgram(0);
+    }
+
+    TEST(ImageEmit, AnInternalFormatChangeAloneStillEmitsTheSet) {
+        EmitterScope scope;
+        const GLuint program = MakeComputeProgram(kImageCompute);
+        GL::UseProgram(program);
+        const GLuint texture = MakeImageTexture();
+        GL::BindImageTexture(1, texture, 0, GL_FALSE, 0, GL_READ_ONLY, GL_RGBA8);
+        Emitter().EmitShaderImages(Ctx());
+        const Uint64 before = Emitter().ImageSetCount();
+        ASSERT_GE(before, 1u);
+        ASSERT_EQ(Emitter().LastImageViews()[1].InternalFormat, static_cast<Uint32>(GL_RGBA8));
+
+        // The format the shader was built against is live glBindImageTexture state, and the
+        // format-less image bake keys on it: a set suppressed because "the binding did not
+        // move" would leave the server baking against the previous format.
+        GL::BindImageTexture(1, texture, 0, GL_FALSE, 0, GL_READ_ONLY, GL_RGBA8UI);
+        Emitter().EmitShaderImages(Ctx());
+        EXPECT_GT(Emitter().ImageSetCount(), before);
+        EXPECT_EQ(Emitter().LastImageViews()[1].InternalFormat, static_cast<Uint32>(GL_RGBA8UI));
+        GL::UseProgram(0);
+    }
+} // namespace
+#endif // MOBILEGL_PIPE_PUSH
+
 int main(int argc, char** argv) {
     namespace fs = std::filesystem;
     const fs::path path =
@@ -334,6 +530,9 @@ int main(int argc, char** argv) {
     _putenv_s("MOBILEGL_LOG_FILE_PATH", g_logPath.c_str());
 #else
     setenv("MOBILEGL_LOG_FILE_PATH", g_logPath.c_str(), 1);
+#endif
+#if MOBILEGL_PIPE_PUSH
+    MobileGL::Initialize();
 #endif
     ::testing::InitGoogleTest(&argc, argv);
     const int rc = RUN_ALL_TESTS();

MobileGL/MG_Test/Pipe/ProgramEmitTest.cpp

@@ -6,20 +6,23 @@
 // SPDX-License-Identifier: LGPL-3.0-only
 // End of Source File Header
 
-// P4a's program family: create/bind/delete_shader_state, set_draw_program,
+// P4a's program family on the client: create/bind/delete_shader_state, set_draw_program,
 // set_dispatch_program and set_global_constants.
 //
-// THE ONE PIN THAT IS EASIEST TO LOSE AND WORST TO LOSE: set_global_constants' Version is
-// GetUBOContentVersion(), and ~0u is the BACKENDS' "never uploaded" sentinel - the wrap skips
-// it - so the client must never emit it. A record carrying the sentinel would tell a backend
-// that a block it has just been handed was never uploaded.
+// THE TWO PROPERTIES THIS SUITE EXISTS FOR, and both are invisible from the emitted bytes:
+//   * THE STAGE MASK COMES FROM THE LINKED SNAPSHOT, never from the live attach list.
+//     glAttachShader and glCompileShader take effect only at the NEXT link and neither moves
+//     the link version, so a descriptor built from the attach list describes a program that
+//     does not exist yet - and it would agree with nothing, because the SPIR-V array beside it
+//     is indexed by the snapshot.
+//   * THE EMITTER JOINS AND THE TRACKER DOES NOT. Bit 6's shutter reads GetCurrentProgram()
+//     deliberately and not GetProgramForDraw(), because the tracker must not force a compile
+//     just to answer "did the shader move"; the join belongs to the emitter, which makes the
+//     same call the verb is about to make anyway.
 //
-// THE SUITE IS `ProgramEmit`, not `ProgramEmitTest`: the file is XTest.cpp and the suite is X,
-// this directory's convention, and it is what the gates grep for.
+// THE SUITE IS `ProgramEmit`, not `ProgramEmitTest`: the file is XTest.cpp and the suite is X.
 //
-// THE TARGET AND ITS ctest REGISTRATION ARE THE CONTRACT COMMIT'S; THE CONTENTS ARE NOT: the
-// applier-side cases are the wire commits' and the emitter-side cases are the client
-// package's, and neither has to come back to MG_Test/Pipe/CMakeLists.txt to add one.
+// THE TARGET AND ITS ctest REGISTRATION ARE THE CONTRACT COMMIT'S; THE CONTENTS ARE NOT.
 //
 // IT HAS ITS OWN main() for ResourceEmitTest's reason. Every case is a visible SKIP in a pull
 // build rather than a vanishing test, so `ctest -N` stays name-for-name identical between the
@@ -46,12 +49,17 @@
 #include "Includes.h"
 #include <MG_Pipe/MGPipe.h>
 #if MOBILEGL_PIPE_PUSH
+#include "Init.h"
+#include <MG_Impl/GLImpl/Program/GL_Program.h>
 #include <MG_Impl/Pipe/ProgramEmit.h>
+#include <MG_Impl/Pipe/SlotAllocator.h>
+#include <MG_Impl/Pipe/Tracker.h>
 #include <MG_Pipe/PipeApply.h>
 // The applier takes the two artefact structs BY POINTER beside the record, so a case that
 // drives create_shader_state needs their definitions - the applier's own header deliberately
 // only forward-declares them.
 #include <MG_State/GLState/ProgramState/ProgramArtifacts.h>
+#include <MG_State/GLState/Core.h>
 #endif
 
 using namespace MobileGL;
@@ -69,13 +77,24 @@ namespace {
     }
 
 #if MOBILEGL_PIPE_PUSH
-    std::string ReadLog() {
+    // `from` is a byte offset, and it exists because of the fork below: the library's log file
+    // is already open by the time a case runs, so the child's lines are APPENDED to it rather
+    // than written to a fresh file, and only what the child appended is this drive's evidence.
+    std::string ReadLog(std::streamoff from = 0) {
         std::ifstream in(g_logPath, std::ios::binary);
+        if (from > 0) in.seekg(from, std::ios::beg);
         std::ostringstream ss;
         ss << in.rdbuf();
         return ss.str();
     }
 
+    // Where the library's log file currently ends. Reading from here after the child has
+    // aborted gives exactly the lines that drive produced.
+    std::streamoff LogEnd() {
+        std::ifstream in(g_logPath, std::ios::binary | std::ios::ate);
+        return in ? static_cast<std::streamoff>(in.tellg()) : std::streamoff{0};
+    }
+
     // A fresh applier per case, BOTH SCOPES, and it takes both because there are two: a reset
     // is a make-current and deliberately KEEPS the object records, so a fixture that wants a
     // genuinely empty applier has to say the other one as well. Every case is its own process
@@ -101,8 +120,14 @@ namespace {
     template <class Body>
     ChildResult RunInChild(Body body) {
         ChildResult result;
-        std::error_code ec;
-        std::filesystem::remove(g_logPath, ec);
+        // THE LOG PATH IS NOT UNLINKED HERE, and that is what this helper had to learn when the
+        // client's cases landed in the same file as the applier's: main() calls
+        // MobileGL::Initialize(), so the library's log FILE* is already open on this path and
+        // fork() duplicates it. Removing the path would leave the child writing into a deleted
+        // inode and the parent reading an empty file - the child would still abort, and the
+        // assertion on WHAT it named could never see the line. So the log's end is remembered
+        // and only what the child appended is read back.
+        const std::streamoff before = LogEnd();
         std::fflush(nullptr);
         const pid_t pid = ::fork();
         if (pid < 0) return result;
@@ -113,7 +138,7 @@ namespace {
         int status = 0;
         if (::waitpid(pid, &status, 0) != pid) return result;
         result.Status = status;
-        result.Log = ReadLog();
+        result.Log = ReadLog(before);
         return result;
     }
 
@@ -161,10 +186,6 @@ TEST(ProgramEmit, TheEmitterIsOneNeverDestroyedProcessSingleton) {
     EXPECT_EQ(&MGPipeProgramEmitterInstance(), &MGPipeProgramEmitterInstance());
     EXPECT_TRUE(kMGPipeWiredProgramSubsystem == 0 ||
                 kMGPipeWiredProgramSubsystem == kMGPipeSubsystemPrograms);
-    // The record the applier starts from carries the sentinel, not 0: a program that has never
-    // published a default-uniform-block image must not look like one that published version 0.
-    const MGPipeShaderCsoRecord fresh{};
-    EXPECT_EQ(fresh.GlobalConstantsVersion, ~Uint32{0});
 #else
     GTEST_SKIP() << "MOBILEGL_PIPE_PUSH is off: there is no client emitter in a pull build";
 #endif
@@ -471,6 +492,291 @@ TEST(ProgramEmit, TheProgramRecordSurvivesAMakeCurrentWhileTheThreeBindingsDoNot
 #endif
 }
 
+#if !MOBILEGL_PIPE_PUSH
+// G2 requires the pull and push ctest name sets to be identical, name for name.
+#define MGL_PROGRAM_EMIT_TEST_LIST(X)                                                              \
+    X(ProgramEmit, TheStageMaskComesFromTheLinkedSnapshotAndNotTheAttachList)                       \
+    X(ProgramEmit, TheNeverUploadedSentinelIsNeverEmitted)                                          \
+    X(ProgramEmit, TheEmitterJoinsAndTheTrackerDoesNot)                                             \
+    X(ProgramEmit, AReLinkReIssuesOnTheSameHandle)                                                  \
+    X(ProgramEmit, TheDrawAndDispatchProgramsAreTwoIndependentSlots)                                \
+    X(ProgramEmit, AnUnchangedProgramEmitsNothingAtAll)                                             \
+    X(ProgramEmit, AReIssuedCreateReSendsTheDefaultUniformBlock)
+
+#define MGL_DECLARE_PULL_SKIP(Suite, Name)                                                         \
+    TEST(Suite, Name) { GTEST_SKIP() << "compiled only under MOBILEGL_PIPE_PUSH"; }
+MGL_PROGRAM_EMIT_TEST_LIST(MGL_DECLARE_PULL_SKIP)
+#undef MGL_DECLARE_PULL_SKIP
+#else
+
+namespace {
+    namespace GL = MobileGL::MG_Impl::GLImpl;
+    using GLContext = MG_State::GLState::GLContext;
+    using MG_State::GLState::ProgramObject;
+
+    struct EmitterScope {
+        EmitterScope() { Clear(); }
+        ~EmitterScope() {
+            GL::UseProgram(0);
+            Clear();
+        }
+        EmitterScope(const EmitterScope&) = delete;
+        EmitterScope& operator=(const EmitterScope&) = delete;
+
+        static void Clear() {
+            MGPipeProgramEmitterInstance().Reset();
+            MGPipeProgramEmitterInstance().ResetCounters();
+        }
+    };
+
+    GLContext& Ctx() { return *MG_State::pGLContext; }
+    MGPipeProgramEmitter& Emitter() { return MGPipeProgramEmitterInstance(); }
+
+    const char* kVs = R"(#version 430 core
+uniform vec4 u_value;
+void main() { gl_Position = u_value; }
+)";
+    const char* kFs = R"(#version 430 core
+out vec4 o_color;
+void main() { o_color = vec4(1.0); }
+)";
+    const char* kGs = R"(#version 430 core
+layout(points) in;
+layout(points, max_vertices = 1) out;
+void main() { gl_Position = vec4(0.0); EmitVertex(); }
+)";
+
+    GLuint MakeShader(GLenum stage, const char* source) {
+        const GLuint shader = GL::CreateShader(stage);
+        GL::ShaderSource(shader, 1, &source, nullptr);
+        GL::CompileShader(shader);
+        return shader;
+    }
+
+    GLuint MakeVsFsProgram() {
+        const GLuint program = GL::CreateProgram();
+        GL::AttachShader(program, MakeShader(GL_VERTEX_SHADER, kVs));
+        GL::AttachShader(program, MakeShader(GL_FRAGMENT_SHADER, kFs));
+        GL::LinkProgram(program);
+        GLint linked = GL_FALSE;
+        GL::GetProgramiv(program, GL_LINK_STATUS, &linked);
+        EXPECT_EQ(linked, GL_TRUE) << "the vertex/fragment program did not link";
+        return program;
+    }
+
+    constexpr Uint32 StageBit(ShaderStage stage) { return Uint32{1} << static_cast<Uint32>(stage); }
+
+    // ProgramObject.h says it in as many words and this is the case that holds it: a stage mask
+    // built from the ATTACH list would describe a program that does not exist yet, because
+    // glAttachShader takes effect only at the next link and does not move the link version.
+    // The SPIR-V array beside the mask is indexed by the same snapshot, so the two halves of
+    // the descriptor agree by construction rather than by care.
+    TEST(ProgramEmit, TheStageMaskComesFromTheLinkedSnapshotAndNotTheAttachList) {
+        EmitterScope scope;
+        const GLuint name = MakeVsFsProgram();
+        const SharedPtr<ProgramObject>& program = Ctx().GetProgramObject(name);
+        ASSERT_TRUE(program);
+        const Uint32 linkedMask = MGPipeStageMaskOf(*program);
+        EXPECT_EQ(linkedMask, StageBit(ShaderStage::Vertex) | StageBit(ShaderStage::Fragment));
+
+        // A third stage is attached and NOT linked. The live attach list now has three
+        // shaders; the mask must not move.
+        GL::AttachShader(name, MakeShader(GL_GEOMETRY_SHADER, kGs));
+        EXPECT_EQ(program->GetAttachedShaders().size(), 3u) << "the attach really has to land";
+        EXPECT_EQ(MGPipeStageMaskOf(*program), linkedMask)
+            << "glAttachShader takes effect at the NEXT link and moves no link version";
+
+        GL::LinkProgram(name);
+        GLint linked = GL_FALSE;
+        GL::GetProgramiv(name, GL_LINK_STATUS, &linked);
+        if (linked == GL_TRUE) {
+            EXPECT_EQ(MGPipeStageMaskOf(*program), linkedMask | StageBit(ShaderStage::Geometry))
+                << "and after the relink the snapshot really does carry it";
+        }
+    }
+
+    // D-H6. ~0u is the backends' "never uploaded" sentinel and the frontend's own wrap skips
+    // it; the client must never put it on the wire either, or a server would read its own
+    // record as "nothing has ever been uploaded here" and re-upload for ever.
+    //
+    // PINNED AS A PREDICATE rather than by driving the counter to ~0u, and the reason is
+    // written down instead of hidden: reaching that value takes four billion
+    // MarkUBOContentDirty calls, which is not a test. The predicate is the thing
+    // EmitGlobalConstants consults, so pinning it pins the behaviour, and a deletion of the
+    // guard is a compile error here.
+    TEST(ProgramEmit, TheNeverUploadedSentinelIsNeverEmitted) {
+        EmitterScope scope;
+        EXPECT_EQ(kMGPipeGlobalConstantsNeverUploaded, ~Uint32{0});
+        EXPECT_FALSE(MGPipeGlobalConstantsVersionIsEmittable(kMGPipeGlobalConstantsNeverUploaded));
+        EXPECT_TRUE(MGPipeGlobalConstantsVersionIsEmittable(0u));
+        EXPECT_TRUE(MGPipeGlobalConstantsVersionIsEmittable(1u));
+        EXPECT_TRUE(MGPipeGlobalConstantsVersionIsEmittable(~Uint32{0} - 1u));
+
+        // And the live path never produces it either: whatever the frontend's counter is at,
+        // the record the emitter last built carries an emittable version.
+        const GLuint name = MakeVsFsProgram();
+        GL::UseProgram(name);
+        const SharedPtr<ProgramObject>& program = Ctx().GetProgramObject(name);
+        ASSERT_TRUE(program);
+        program->MarkUBOContentDirty();
+        if (Emitter().EmitGlobalConstants(Ctx()) > 0u) {
+            EXPECT_TRUE(MGPipeGlobalConstantsVersionIsEmittable(Emitter().LastGlobalConstants().Version));
+            EXPECT_EQ(Emitter().LastGlobalConstants().Version, program->GetUBOContentVersion());
+            EXPECT_EQ(Emitter().LastGlobalConstants().Blob.Size, 0u)
+                << "the one Blob rule: a monolith emission does not declare its blob";
+        }
+    }
+
+    // D-H4, and it is a statement about the TRACKER as much as about the emitter: Update() may
+    // not move a program's link completeness in either direction, because answering "did the
+    // shader move" from a version counter is what keeps a compile off the dirty walk. The
+    // emitter is where the join belongs, and it is the same GetProgramForDraw() the verb is
+    // about to make anyway.
+    TEST(ProgramEmit, TheEmitterJoinsAndTheTrackerDoesNot) {
+        EmitterScope scope;
+        const GLuint name = MakeVsFsProgram();
+        GL::UseProgram(name);
+        const SharedPtr<ProgramObject>& program = Ctx().GetProgramObject(name);
+        ASSERT_TRUE(program);
+
+        const Bool completeBefore = program->IsLinkComplete();
+        MGPipeTrackerInstance().Update(Ctx(), MGPipeVerbClass::kDraw);
+        EXPECT_EQ(program->IsLinkComplete(), completeBefore)
+            << "the dirty walk must not force a compile, in either direction";
+
+        Emitter().EmitShaderState(Ctx());
+        EXPECT_TRUE(program->IsLinkComplete()) << "the emitter joins, because the verb would";
+        MGPipeTrackerInstance().Reset();
+    }
+
+    TEST(ProgramEmit, AReLinkReIssuesOnTheSameHandle) {
+        EmitterScope scope;
+        const GLuint name = MakeVsFsProgram();
+        GL::UseProgram(name);
+        const SharedPtr<ProgramObject>& program = Ctx().GetProgramObject(name);
+        ASSERT_TRUE(program);
+
+        ASSERT_GT(Emitter().EmitShaderState(Ctx()), 0u);
+        ASSERT_EQ(Emitter().CreateCount(), 1u);
+        const MGPipeHandle cso = Emitter().LastProgramDesc().Cso;
+        EXPECT_FALSE(MGPipeHandleIsNull(cso));
+        EXPECT_EQ(Emitter().DrawCso(), cso);
+
+        // Nothing moved: no second record, no second bind.
+        Emitter().EmitShaderState(Ctx());
+        EXPECT_EQ(Emitter().CreateCount(), 1u);
+        EXPECT_EQ(Emitter().BindCount(), 1u);
+
+        const Uint32 linkVersionBefore = program->GetLinkVersion();
+        GL::LinkProgram(name);
+        ASSERT_NE(program->GetLinkVersion(), linkVersionBefore) << "the relink really has to move it";
+
+        Emitter().EmitShaderState(Ctx());
+        EXPECT_EQ(Emitter().CreateCount(), 2u);
+        // THE SAME HANDLE. Gen increments only on slot reuse and never on a respecify, so a
+        // relinked program is the same GL object and the server's twin table must not be asked
+        // to mint a second identity for it.
+        EXPECT_EQ(Emitter().LastProgramDesc().Cso, cso);
+        EXPECT_EQ(Emitter().BindCount(), 1u) << "and a re-issue on the bound handle is not a rebind";
+    }
+
+    // Two calls because the frontend has two joins and two PipeInputs slots. With a plain
+    // glUseProgram they name one object, and the record has to say so rather than leaving the
+    // server to guess which of the two a verb meant.
+    TEST(ProgramEmit, TheDrawAndDispatchProgramsAreTwoIndependentSlots) {
+        EmitterScope scope;
+        const GLuint name = MakeVsFsProgram();
+        GL::UseProgram(name);
+        ASSERT_GT(Emitter().EmitShaderState(Ctx()), 0u);
+        EXPECT_EQ(Emitter().DrawCso(), Emitter().DispatchCso());
+        EXPECT_EQ(Emitter().BoundCso(), Emitter().DrawCso());
+        EXPECT_EQ(Emitter().DrawProgramSetCount(), 1u);
+        EXPECT_EQ(Emitter().DispatchProgramSetCount(), 1u);
+
+        // A null handle is legal and means exactly "nothing bound".
+        GL::UseProgram(0);
+        Emitter().EmitShaderState(Ctx());
+        EXPECT_TRUE(MGPipeHandleIsNull(Emitter().DrawCso()));
+        EXPECT_TRUE(MGPipeHandleIsNull(Emitter().DispatchCso()));
+        EXPECT_TRUE(MGPipeHandleIsNull(Emitter().BoundCso()));
+        EXPECT_EQ(Emitter().DrawProgramSetCount(), 2u);
+    }
+
+    TEST(ProgramEmit, AnUnchangedProgramEmitsNothingAtAll) {
+        EmitterScope scope;
+        const GLuint name = MakeVsFsProgram();
+        GL::UseProgram(name);
+        ASSERT_GT(Emitter().EmitShaderState(Ctx()), 0u);
+        // The version-first skip: nothing hashed, nothing copied, nothing emitted, and the
+        // return value is the bytes that went on the wire - zero.
+        EXPECT_EQ(Emitter().EmitShaderState(Ctx()), 0u);
+        EXPECT_EQ(Emitter().CreateCount(), 1u);
+        EXPECT_EQ(Emitter().BindCount(), 1u);
+        EXPECT_EQ(Emitter().DrawProgramSetCount(), 1u);
+    }
+
+    // set_global_constants is suppressed against a (ShaderCso, Version) key, and A RE-ISSUED
+    // create_shader_state CLEARS THE APPLIER's DEFAULT UNIFORM BLOCK (wire's W6). So the key
+    // has to die with the re-issue, or the block is never re-sent and the server draws the
+    // program with a zeroed one while the client's scratch still holds the live values.
+    //
+    // WHICH HALF OF THIS CASE IS THE DISCRIMINATOR, said plainly. The second half - "the block
+    // goes out again after a relink" - is also true without the fix, because
+    // BumpLinkObservableVersions bumps the UBO content version alongside the link version, so
+    // the Version half of the key moves on its own for the one re-issue trigger that exists
+    // today. The FIRST half is the one that goes red when the invalidation is deleted, and it
+    // is the property the contract actually needs: after a re-issue the emitter must hold NO
+    // key at all, so no future re-issue trigger - a recycled slot, a re-issue driven by
+    // anything that does not happen to move the content version - can leave the applier's
+    // cleared block latched as "already sent".
+    TEST(ProgramEmit, AReIssuedCreateReSendsTheDefaultUniformBlock) {
+        EmitterScope scope;
+        const GLuint name = MakeVsFsProgram();
+        GL::UseProgram(name);
+        const SharedPtr<ProgramObject>& program = Ctx().GetProgramObject(name);
+        ASSERT_TRUE(program);
+
+        ASSERT_GT(Emitter().EmitShaderState(Ctx()), 0u);
+        ASSERT_EQ(Emitter().CreateCount(), 1u);
+        // Driven to the fixed point rather than assumed to settle in one call: the first
+        // EmitGlobalConstants reads GetUBOContentVersion() BEFORE GetUBOSize() joins phase B,
+        // and that join bumps the counter, so the first key is one behind by construction.
+        for (int i = 0; i < 8 && Emitter().EmitGlobalConstants(Ctx()) > 0u; ++i) {
+        }
+        const Uint64 setsBefore = Emitter().GlobalConstantsSetCount();
+        ASSERT_GT(setsBefore, 0u) << "this program declares a uniform, so a block must have gone out";
+        const MGPipeHandle cso = Emitter().GlobalConstantsCso();
+        ASSERT_FALSE(MGPipeHandleIsNull(cso));
+        EXPECT_EQ(cso, Emitter().DrawCso());
+        // The latch really is latched.
+        EXPECT_EQ(Emitter().EmitGlobalConstants(Ctx()), 0u);
+        EXPECT_EQ(Emitter().GlobalConstantsSetCount(), setsBefore);
+
+        // A RELINK, which is the one thing that makes AcquireShaderCso re-issue on the same
+        // handle. A failed relink is the case the design worries about - GL keeps a program
+        // that is active for a stage running on its previous executable - and this frontend
+        // additionally clears the phase-B scratch in Link()'s prologue, so the populated-block
+        // half of that scenario is not reachable here; the re-issue is, and it is what the
+        // applier reacts to.
+        const Uint32 linkVersionBefore = program->GetLinkVersion();
+        GL::LinkProgram(name);
+        ASSERT_NE(program->GetLinkVersion(), linkVersionBefore) << "the relink really has to move it";
+
+        Emitter().EmitShaderState(Ctx());
+        ASSERT_EQ(Emitter().CreateCount(), 2u) << "the create really has to be re-issued";
+        EXPECT_TRUE(MGPipeHandleIsNull(Emitter().GlobalConstantsCso()))
+            << "the applier cleared the record's default uniform block on the re-issue, so the "
+               "key that suppresses set_global_constants must not survive it";
+        EXPECT_EQ(Emitter().GlobalConstantsVersion(), kMGPipeGlobalConstantsNeverUploaded);
+
+        // And the block really is sent again.
+        for (int i = 0; i < 8 && Emitter().EmitGlobalConstants(Ctx()) > 0u; ++i) {
+        }
+        EXPECT_GT(Emitter().GlobalConstantsSetCount(), setsBefore);
+    }
+} // namespace
+#endif // MOBILEGL_PIPE_PUSH
+
 int main(int argc, char** argv) {
     namespace fs = std::filesystem;
     const fs::path path =
@@ -482,6 +788,9 @@ int main(int argc, char** argv) {
     _putenv_s("MOBILEGL_LOG_FILE_PATH", g_logPath.c_str());
 #else
     setenv("MOBILEGL_LOG_FILE_PATH", g_logPath.c_str(), 1);
+#endif
+#if MOBILEGL_PIPE_PUSH
+    MobileGL::Initialize();
 #endif
     ::testing::InitGoogleTest(&argc, argv);
     const int rc = RUN_ALL_TESTS();

MobileGL/MG_Test/Pipe/ResourceEmitTest.cpp

@@ -156,6 +156,27 @@ namespace {
         }
     };
 
+    // "A BACKEND IS PRESENT", which since ID-39 is a thing the applier ASKS: every P4a-family
+    // entry point declines a record - and counts RefusedNoConsumer - when no backend has
+    // registered MGPipeResourceOps, because acceptance is a contract with the emitter and an
+    // accepted record nothing will read makes the client clear a dirty flag the legacy pull
+    // path still owed. A case that wants the P4a half of this applier to behave as it does
+    // under DirectGLES scopes this on; the case that wants the OTHER arm simply does not.
+    //
+    // THE TABLE IS EMPTY AND THAT IS DELIBERATE. Its hooks are the BUFFER family's, and every
+    // non-buffer resource row is stored and returned rather than dispatched (see
+    // MGPipeApplyResourceCreate) - so what registering it changes here is the consumer question
+    // and nothing else. It nests: the previous table is restored, not nulled.
+    struct ScopedResourceOps {
+        ScopedResourceOps() : m_saved(MGPipeGetResourceOps()) {
+            static const MGPipeResourceOps kEmpty{};
+            MGPipeSetResourceOps(&kEmpty);
+        }
+        ~ScopedResourceOps() { MGPipeSetResourceOps(m_saved); }
+
+        const MGPipeResourceOps* m_saved;
+    };
+
     MGPResourceDesc BufferDesc(MGPipeHandle res, Uint32 width, Uint32 glName) {
         MGPResourceDesc desc{};
         desc.Resource = res;
@@ -1355,6 +1376,9 @@ namespace {
         GTEST_SKIP() << "MOBILEGL_PIPE_PUSH is off: there is no applier in this build";
 #else
         ApplierGuard guard;
+        // The texture and renderbuffer rows below are P4a's, and P4a's belt declines those on a
+        // backend that consumes none of them (ID-39) - so this case says which arm it is about.
+        ScopedResourceOps consumer;
         const MGPipeHandle shared{7, 3};
 
         MGPipeApplyResourceCreate(TargetedDesc(shared, MGPipeResourceTarget::Buffer, 0, 11));
@@ -1393,6 +1417,195 @@ namespace {
 #endif
     }
 
+    // ID-39: THE APPLIER'S HALF OF THE "NO CONSUMER" RULE, over every P4a-family entry point.
+    //
+    // WHY AN APPLIER ASKS A QUESTION ABOUT THE BACKEND AT ALL is written beside
+    // MGPipeApplierState::RefusedNoConsumer: acceptance became a CONTRACT WITH THE CLIENT at
+    // ID-18 M3 - the emitters clear a texture level's dirty flags, advance their descriptor
+    // mirrors and latch their suppressors on the answer these calls return - so an applier that
+    // accepts a record nothing in the process will ever read makes the client forget work the
+    // legacy pull path still owed. On DirectVulkan, which registers no MGPipeResourceOps and
+    // has none of P4a's twins, that put 66 texture-upload-shaped integration-gpu cases red on
+    // the push build while the pull build stayed 966/966 green.
+    //
+    // IT IS A BELT AND NOT THE GATE. The client's gate is FamilyIsLive in
+    // MG_Impl/Pipe/PipeFill.cpp (pinned by TextureEmit.WithNoBackendConsumerTheFamilyGateIsFalse
+    // AndNothingReachesTheApplier) and it stops the emission upstream. This is under it, and it
+    // is not redundant: GL_Framebuffer.cpp's PipePublishFramebufferByName reaches the
+    // framebuffer emitter DIRECTLY at the fifteen DSA sites, without passing through PipeFill,
+    // so set_framebuffer_state is a record that can arrive here on a backend with no consumer.
+    //
+    // THE DEATH PATHS ARE DELIBERATELY NOT IN THE LIST and the second half of the case says so:
+    // a destroy is idempotent cleanup that must keep working whatever the registration did.
+    TEST(ResourceEmit, EveryP4aFamilyEntryPointDeclinesWhenNoBackendRegisteredTheConsumer) {
+#if !MOBILEGL_PIPE_PUSH
+        GTEST_SKIP() << "MOBILEGL_PIPE_PUSH is off: there is no applier in this build";
+#else
+        ApplierGuard guard; // leaves the table UNREGISTERED, which is this half's whole point
+        ASSERT_EQ(MGPipeGetResourceOps(), nullptr);
+
+        const MGPipeHandle texture{7, 3};
+        const MGPipeHandle cso{9, 1};
+        const MGPipeHandle fbo{4, 2};
+
+        MGPTextureParams params{};
+        params.Res = texture;
+        params.BuiltinSampler = cso;
+
+        MGPSubData upload{};
+        upload.Res = texture;
+        upload.Target = MGPipePackSubDataTarget(static_cast<Uint32>(MGPipeResourceTarget::Tex2D), 0u);
+
+        MGPFramebufferState fboState{};
+        fboState.Fbo = fbo;
+        fboState.Target = static_cast<Uint8>(MGPipeFramebufferTarget::Draw);
+
+        MGPSamplerDesc samplerDesc{};
+        samplerDesc.Cso = cso;
+        const SamplerParameters samplerParams{};
+
+        MGPSamplerView view{};
+        view.Cso = cso;
+        view.Texture = texture;
+
+        const MGPSamplerViews viewSet{0, 1, 0};
+        const MGPBoundView viewTail[1]{};
+        const MGPSamplerStates stateSet{0, 1, 0};
+        const MGPipeHandle stateTail[1]{kMGPipeNullHandle};
+        const MGPShaderImages imageSet{0, 1, 0};
+        const MGPImageView imageTail[1]{};
+
+        MGPProgramDesc program{};
+        program.Cso = cso;
+        program.StageMask = 0x3u;
+        const MG_State::GLState::LinkArtifacts link;
+        const MG_State::GLState::SpirvArtifacts spirv;
+
+        MGPGlobalConstants constants{};
+        constants.ShaderCso = cso;
+
+        const MGPHandleOnly csoHandle{cso, static_cast<Uint32>(MGPipeKind::ShaderCso), 0};
+
+        // ---- with no consumer: every one of them declines, and NOTHING is stored ----
+        EXPECT_FALSE(MGPipeApplyResourceCreate(TargetedDesc(texture, MGPipeResourceTarget::Tex2D, 0, 22)));
+        EXPECT_FALSE(
+            MGPipeApplyResourceRespecify(TargetedDesc(texture, MGPipeResourceTarget::Tex2D, 64, 22), nullptr));
+        EXPECT_FALSE(MGPipeApplyResourceSubData(upload, nullptr));
+        MGPipeApplySetTextureParams(params);
+        MGPipeApplySetFramebufferState(fboState);
+        MGPipeApplyCreateSamplerState(samplerDesc, &samplerParams);
+        MGPipeApplyCreateSamplerView(view);
+        MGPipeApplySetSamplerViews(viewSet, viewTail);
+        MGPipeApplyBindSamplerStates(stateSet, stateTail);
+        MGPipeApplySetShaderImages(imageSet, imageTail);
+        MGPipeApplyCreateShaderState(program, &link, &spirv);
+        MGPipeApplyBindShaderState(csoHandle);
+        MGPipeApplySetDrawProgram(csoHandle);
+        MGPipeApplySetDispatchProgram(csoHandle);
+        MGPipeApplySetGlobalConstants(constants, nullptr);
+
+        // FIFTEEN CALLS, FIFTEEN REFUSALS, AND THE NUMBER IS THE ASSERTION: an entry point that
+        // is added to a P4a family later and forgets the belt makes this line fail rather than
+        // silently accepting a record on a backend that reads none.
+        EXPECT_EQ(MGPipeApplier().RefusedNoConsumer, 15u);
+        // AND NOT ONE OF THE OTHER THREE MOVED. The refusal is a configuration fact, not a seam
+        // defect, so it must not read as one to an operator grepping the counters.
+        EXPECT_EQ(MGPipeApplier().RefusedResourceCalls, 0u);
+        EXPECT_EQ(MGPipeApplier().RefusedObjectCalls, 0u);
+        EXPECT_EQ(MGPipeApplier().StaleFramebufferRecordLookups, 0u);
+
+        // NOTHING IS LIVE, which is the property, rather than "no table exists". The belt stands
+        // AFTER each entry point's own record-shape checks so that a malformed record is
+        // Fatal{ProtocolCorruption} on every backend and not only on the ones that consume - and
+        // the bound check for the four create-shaped calls IS RecordAt, which grows the table to
+        // the slot on its way to answering. So a refused create may leave a zeroed row behind
+        // and stores nothing in it. It costs nothing where it matters: on a backend with no
+        // consumer the client's gate emits none of these at all, and the one record that reaches
+        // this applier without passing that gate - set_framebuffer_state, published by name from
+        // GL_Framebuffer.cpp - is declined in front of its RecordAt.
+        const auto nothingLiveAt = [](const auto& table, SizeT slot) {
+            return table.size() <= slot || !table[slot].Live;
+        };
+        EXPECT_TRUE(nothingLiveAt(MGPipeApplier().TextureResources, 7));
+        EXPECT_TRUE(nothingLiveAt(MGPipeApplier().SamplerCsos, 9));
+        EXPECT_TRUE(nothingLiveAt(MGPipeApplier().SamplerViewCsos, 9));
+        EXPECT_TRUE(nothingLiveAt(MGPipeApplier().ShaderCsos, 9));
+        // set_framebuffer_state's table is the one that must not even be grown: it is declined
+        // in front of its RecordAt, because it is the one call a backend with no consumer can
+        // actually receive.
+        EXPECT_TRUE(MGPipeApplier().FramebufferRecords.empty());
+        EXPECT_EQ(MGPipeApplier().SamplerViewCount, 0u);
+        EXPECT_EQ(MGPipeApplier().SamplerStateCount, 0u);
+        EXPECT_EQ(MGPipeApplier().ShaderImageCount, 0u);
+        EXPECT_TRUE(MGPipeHandleIsNull(MGPipeApplier().BoundShaderCso));
+        EXPECT_TRUE(MGPipeHandleIsNull(MGPipeApplier().DrawProgram));
+        EXPECT_TRUE(MGPipeHandleIsNull(MGPipeApplier().DispatchProgram));
+        EXPECT_TRUE(MGPipeHandleIsNull(
+            MGPipeApplier().BoundFramebuffer[static_cast<SizeT>(MGPipeFramebufferTarget::Draw)]));
+
+        // ---- and with one, every one of them lands. Same records, same order ----
+        {
+            ScopedResourceOps consumer;
+            const Uint64 refusalsBefore = MGPipeApplier().RefusedNoConsumer;
+
+            EXPECT_TRUE(
+                MGPipeApplyResourceCreate(TargetedDesc(texture, MGPipeResourceTarget::Tex2D, 0, 22)));
+            EXPECT_TRUE(MGPipeApplyResourceRespecify(
+                TargetedDesc(texture, MGPipeResourceTarget::Tex2D, 64, 22), nullptr));
+            MGPipeApplySetTextureParams(params);
+            MGPipeApplySetFramebufferState(fboState);
+            MGPipeApplyCreateSamplerState(samplerDesc, &samplerParams);
+            MGPipeApplyCreateSamplerView(view);
+            MGPipeApplySetSamplerViews(viewSet, viewTail);
+            MGPipeApplyBindSamplerStates(stateSet, stateTail);
+            MGPipeApplySetShaderImages(imageSet, imageTail);
+            MGPipeApplyCreateShaderState(program, &link, &spirv);
+            MGPipeApplyBindShaderState(csoHandle);
+            MGPipeApplySetDrawProgram(csoHandle);
+            MGPipeApplySetDispatchProgram(csoHandle);
+            MGPipeApplySetGlobalConstants(constants, nullptr);
+
+            EXPECT_EQ(MGPipeApplier().RefusedNoConsumer, refusalsBefore);
+            ASSERT_GT(MGPipeApplier().TextureResources.size(), 7u);
+            EXPECT_TRUE(MGPipeApplier().TextureResources[7].Live);
+            EXPECT_EQ(MGPipeApplier().TextureResources[7].Desc.Width, 64u);
+            EXPECT_EQ(MGPipeApplier().TextureResources[7].Params.BuiltinSampler, cso);
+            ASSERT_GT(MGPipeApplier().FramebufferRecords.size(), 4u);
+            EXPECT_TRUE(MGPipeApplier().FramebufferRecords[4].Live);
+            EXPECT_EQ(MGPipeApplier().BoundFramebuffer[static_cast<SizeT>(MGPipeFramebufferTarget::Draw)],
+                      fbo);
+            ASSERT_GT(MGPipeApplier().SamplerCsos.size(), 9u);
+            EXPECT_TRUE(MGPipeApplier().SamplerCsos[9].Live);
+            ASSERT_GT(MGPipeApplier().SamplerViewCsos.size(), 9u);
+            EXPECT_TRUE(MGPipeApplier().SamplerViewCsos[9].Live);
+            ASSERT_GT(MGPipeApplier().ShaderCsos.size(), 9u);
+            EXPECT_TRUE(MGPipeApplier().ShaderCsos[9].Live);
+            EXPECT_EQ(MGPipeApplier().SamplerViewCount, 1u);
+            EXPECT_EQ(MGPipeApplier().SamplerStateCount, 1u);
+            EXPECT_EQ(MGPipeApplier().ShaderImageCount, 1u);
+            EXPECT_EQ(MGPipeApplier().BoundShaderCso, cso);
+            EXPECT_EQ(MGPipeApplier().DrawProgram, cso);
+            EXPECT_EQ(MGPipeApplier().DispatchProgram, cso);
+            // resource_subdata's ACCEPTED path wants a real destination box against real
+            // storage, which is a texture-emitter fixture and not this file's; it is proved end
+            // to end by TextureEmit.WithNoBackendConsumerTheFamilyGateIsFalseAndNothingReaches
+            // TheApplier's second half (SubDataCount 1, RefusedSubDataCount 0). Driving a
+            // half-built record through it here would trip the upload validator's own wire,
+            // which is a different rule and not this case's.
+
+            // AND THE DEATH PATHS ARE NOT BELTED, which is the other half of the ruling: they
+            // are idempotent cleanup and they run on whatever the registration is. Driven with
+            // the table registered here and asserted UNCOUNTED, so that a later commit which
+            // adds them to the belt has to change this line.
+            MGPipeApplyDeleteShaderState(csoHandle);
+            MGPipeApplyResourceDestroy(KindHandle(texture, MGPipeKind::Texture));
+            EXPECT_EQ(MGPipeApplier().RefusedNoConsumer, refusalsBefore);
+            EXPECT_FALSE(MGPipeApplier().ShaderCsos[9].Live);
+            EXPECT_FALSE(MGPipeApplier().TextureResources[7].Live);
+        }
+#endif
+    }
+
     // Neither branch may fall through to a table it was not named. A target or a kind outside
     // the catalogue would otherwise land in whichever table the code happened to reach first,
     // and destroy a live object of a kind the call was never about.

MobileGL/MG_Test/Pipe/SamplerEmitTest.cpp

@@ -53,8 +53,16 @@
 #include "Includes.h"
 #include <MG_Pipe/MGPipe.h>
 #if MOBILEGL_PIPE_PUSH
+#include <cstring>
+
+#include "Init.h"
+#include <MG_Impl/GLImpl/Program/GL_Program.h>
+#include <MG_Impl/GLImpl/Texture/GL_Texture.h>
 #include <MG_Impl/Pipe/SamplerEmit.h>
+#include <MG_Impl/Pipe/SetHashSuppressor.h>
+#include <MG_Impl/Pipe/SlotAllocator.h>
 #include <MG_Pipe/PipeApply.h>
+#include <MG_State/GLState/Core.h>
 #endif
 
 using namespace MobileGL;
@@ -72,13 +80,24 @@ namespace {
     }
 
 #if MOBILEGL_PIPE_PUSH
-    std::string ReadLog() {
+    // `from` is a byte offset, and it exists because of the fork below: the library's log file
+    // is already open by the time a case runs, so the child's lines are APPENDED to it rather
+    // than written to a fresh file, and only what the child appended is this drive's evidence.
+    std::string ReadLog(std::streamoff from = 0) {
         std::ifstream in(g_logPath, std::ios::binary);
+        if (from > 0) in.seekg(from, std::ios::beg);
         std::ostringstream ss;
         ss << in.rdbuf();
         return ss.str();
     }
 
+    // Where the library's log file currently ends. Reading from here after the child has
+    // aborted gives exactly the lines that drive produced.
+    std::streamoff LogEnd() {
+        std::ifstream in(g_logPath, std::ios::binary | std::ios::ate);
+        return in ? static_cast<std::streamoff>(in.tellg()) : std::streamoff{0};
+    }
+
     // A fresh applier per case, BOTH SCOPES, and it takes both because there are two: a reset
     // is a make-current and deliberately KEEPS the object records, so a fixture that wants a
     // genuinely empty applier has to say the other one as well. Every case is its own process
@@ -104,8 +123,14 @@ namespace {
     template <class Body>
     ChildResult RunInChild(Body body) {
         ChildResult result;
-        std::error_code ec;
-        std::filesystem::remove(g_logPath, ec);
+        // THE LOG PATH IS NOT UNLINKED HERE, and that is what this helper had to learn when the
+        // client's cases landed in the same file as the applier's: main() calls
+        // MobileGL::Initialize(), so the library's log FILE* is already open on this path and
+        // fork() duplicates it. Removing the path would leave the child writing into a deleted
+        // inode and the parent reading an empty file - the child would still abort, and the
+        // assertion on WHAT it named could never see the line. So the log's end is remembered
+        // and only what the child appended is read back.
+        const std::streamoff before = LogEnd();
         std::fflush(nullptr);
         const pid_t pid = ::fork();
         if (pid < 0) return result;
@@ -116,7 +141,7 @@ namespace {
         int status = 0;
         if (::waitpid(pid, &status, 0) != pid) return result;
         result.Status = status;
-        result.Log = ReadLog();
+        result.Log = ReadLog(before);
         return result;
     }
 
@@ -524,6 +549,548 @@ TEST(SamplerEmit, AMakeCurrentTakesTheUnitSetsAndLeavesTheCsoAndViewRecordsStand
 #endif
 }
 
+#if !MOBILEGL_PIPE_PUSH
+// G2 requires the pull and push ctest name sets to be identical, name for name, so every
+// push-only case is present here and SKIPS rather than being absent.
+#define MGL_SAMPLER_EMIT_TEST_LIST(X)                                                              \
+    X(SamplerEmit, EverySamplerParameterFieldSurvivesTheBlobConversion)                             \
+    X(SamplerEmit, PaddingCannotChangeTheHash)                                                      \
+    X(SamplerEmit, TwoIdenticalSamplersShareOneCso)                                                 \
+    X(SamplerEmit, ABorderColorFormChangeAloneMintsANewCso)                                         \
+    X(SamplerEmit, AHashCollisionDoesNotAliasTwoSamplerStates)                                      \
+    X(SamplerEmit, AViewIsReIssuedOnTheSameHandleWhenItsRestrictionsMove)                           \
+    X(SamplerEmit, AnUnchangedTextureReIssuesNothing)                                               \
+    X(SamplerEmit, OnlyTheProgramResolvedUnitsAreEmitted)                                           \
+    X(SamplerEmit, AnUnchangedSetEmitsNothing)                                                      \
+    X(SamplerEmit, ARedundantRebindOfTheSameSamplerEmitsNothing)                                    \
+    X(SamplerEmit, ABoundSamplerStateHoldsItsCsoUntilTheUnitMoves)                                  \
+    X(SamplerEmit, AReferencedCsoIsNeverTheLruVictim)                                               \
+    X(SamplerEmit, AFullyPinnedCacheMintsBeyondItsCapacityAndCountsIt)                              \
+    X(SamplerEmit, AReleaseThisCacheNeverHandedOutIsCountedRatherThanAbsorbed)
+
+#define MGL_DECLARE_PULL_SKIP(Suite, Name)                                                         \
+    TEST(Suite, Name) { GTEST_SKIP() << "compiled only under MOBILEGL_PIPE_PUSH"; }
+MGL_SAMPLER_EMIT_TEST_LIST(MGL_DECLARE_PULL_SKIP)
+#undef MGL_DECLARE_PULL_SKIP
+#else
+
+namespace {
+    using GLContext = MG_State::GLState::GLContext;
+    using MG_State::GLState::ITextureObject;
+    using MG_State::GLState::SamplerObject;
+
+    // AN RAII SCOPE RATHER THAN A gtest FIXTURE, for VertexInputEmitTest's reason: both gates
+    // grep `ctest -R 'SamplerEmit\.'`, a TEST_F files its cases under the FIXTURE's name, and
+    // gtest refuses to mix TEST and TEST_F under one suite name.
+    //
+    // UNLIKE VertexInputEmitTest's, this scope does NOT replace pGLContext: half these cases
+    // need a really linked program, so the process is initialised once in main() and the cases
+    // share that context, each using GL names of its own. What the scope does is put the
+    // emitter, its counters and the suppressor back to a known state.
+    struct EmitterScope {
+        EmitterScope() { Clear(); }
+        ~EmitterScope() { Clear(); }
+        EmitterScope(const EmitterScope&) = delete;
+        EmitterScope& operator=(const EmitterScope&) = delete;
+
+        static void Clear() {
+            MGPipeSamplerEmitterInstance().Reset();
+            MGPipeSamplerEmitterInstance().ResetCounters();
+            MGPipeSamplerCsoCacheInstance().ResetForTest();
+            MGPipeSamplerCsoCacheInstance().ResetCounters();
+            MGPipeSetHashSuppressorInstance().InvalidateAll();
+        }
+    };
+
+    GLContext& Ctx() { return *MG_State::pGLContext; }
+    MGPipeSamplerEmitter& Emitter() { return MGPipeSamplerEmitterInstance(); }
+    MGPipeSamplerCsoCache& Cache() { return MGPipeSamplerCsoCacheInstance(); }
+
+    // Every field of SamplerParameters set to a value that is not its default, so a conversion
+    // that dropped one is caught by the field's own EXPECT rather than by a count.
+    SamplerParameters DistinctParameters() {
+        SamplerParameters params{};
+        params.wrapS = SamplerWrapMode::ClampToBorder;
+        params.wrapT = SamplerWrapMode::MirroredRepeat;
+        params.wrapR = SamplerWrapMode::MirrorClampToEdge;
+        params.minFilter = SamplerFilterMode::Linear;
+        params.magFilter = SamplerFilterMode::Nearest;
+        params.mipmapMode = SamplerMipmapMode::Nearest;
+        params.minLod = -3.5f;
+        params.maxLod = 7.25f;
+        params.lodBias = 1.5f;
+        params.maxAnisotropy = 2.0f;
+        params.compareFunc = SamplerCompareFunc::Greater;
+        params.compareMode = SamplerCompareMode::CompareToTexture;
+        params.borderColor = {0.25f, 0.5f, 0.75f, 1.0f};
+        params.borderColorI = {-1, 2, -3, 4};
+        params.borderColorUI = {5u, 6u, 7u, 8u};
+        params.borderColorForm = BorderColorForm::Int;
+        return params;
+    }
+
+    // A 2D texture with a single level and a mipmap mode of None, so it is mipmap-complete for
+    // its filter and therefore actually reaches the emitted set. A texture that samples as
+    // incomplete is dropped to a null view on purpose, which is the resolution DirectGLES
+    // performs by leaving the native target unbound.
+    const SharedPtr<ITextureObject>& MakeCompleteTexture(GLuint& name, Int width) {
+        namespace GL = MobileGL::MG_Impl::GLImpl;
+        GL::GenTextures(1, &name);
+        GL::BindTexture(GL_TEXTURE_2D, name);
+        GL::TexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, width, width, 0, GL_RGBA, GL_UNSIGNED_BYTE, nullptr);
+        GL::TexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+        GL::TexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+        return Ctx().GetTextureObject(name);
+    }
+
+    void BindTextureToUnit(Uint32 unit, const SharedPtr<ITextureObject>& texture) {
+        Ctx().GetTextureUnitObject(static_cast<Int>(unit))
+            .GetBindingSlot(TextureTarget::Texture2D)
+            .Bind(texture);
+        Ctx().NoteTextureUnitTouched(static_cast<Int>(unit));
+    }
+
+    // ============================ D-F1: the CSO cache ============================
+
+    // G6 for this family: every one of SamplerParameters' sixteen members survives the
+    // canonical copy the cache hashes and confirms over. Each member is its own EXPECT naming
+    // that member, which is what G7's scripted control needs - it stops the conversion copying
+    // borderColorForm and expects this case to go red NAMING it.
+    TEST(SamplerEmit, EverySamplerParameterFieldSurvivesTheBlobConversion) {
+        EmitterScope scope;
+        const SamplerParameters source = DistinctParameters();
+        SamplerParameters canon;
+        MGPipeCanonicaliseSamplerParameters(source, canon);
+
+        EXPECT_EQ(canon.wrapS, source.wrapS);
+        EXPECT_EQ(canon.wrapT, source.wrapT);
+        EXPECT_EQ(canon.wrapR, source.wrapR);
+        EXPECT_EQ(canon.minFilter, source.minFilter);
+        EXPECT_EQ(canon.magFilter, source.magFilter);
+        EXPECT_EQ(canon.mipmapMode, source.mipmapMode);
+        EXPECT_EQ(canon.minLod, source.minLod);
+        EXPECT_EQ(canon.maxLod, source.maxLod);
+        EXPECT_EQ(canon.lodBias, source.lodBias);
+        EXPECT_EQ(canon.maxAnisotropy, source.maxAnisotropy);
+        EXPECT_EQ(canon.compareFunc, source.compareFunc);
+        EXPECT_EQ(canon.compareMode, source.compareMode);
+        EXPECT_EQ(canon.borderColor, source.borderColor);
+        EXPECT_EQ(canon.borderColorI, source.borderColorI);
+        EXPECT_EQ(canon.borderColorUI, source.borderColorUI);
+        EXPECT_EQ(canon.borderColorForm, source.borderColorForm)
+            << "borderColorForm decides which of glSamplerParameterIiv / fv applies, and the "
+               "three representations are always numerically populated, so the value alone "
+               "cannot say";
+    }
+
+    // THE PADDING TRAP. SamplerParameters is 100 bytes and its members occupy 97 of them, so
+    // bytes 97..99 are padding no writer ever touches. A cache that hashed the object's own
+    // bytes would read them, miss on every probe and mint a fresh CSO per call - a 256-entry
+    // cache with a hit rate of zero that nobody notices, because the pixels are right.
+    TEST(SamplerEmit, PaddingCannotChangeTheHash) {
+        EmitterScope scope;
+        SamplerParameters clean = DistinctParameters();
+        SamplerParameters dirty = clean;
+        auto* bytes = reinterpret_cast<Uint8*>(&dirty);
+        // Written THROUGH A BYTE POINTER, past the last member and inside the object, which is
+        // the only way to make the difference this case is about.
+        for (SizeT i = 97; i < sizeof(SamplerParameters); ++i) bytes[i] = static_cast<Uint8>(0xA5 + i);
+
+        SamplerParameters canonClean;
+        SamplerParameters canonDirty;
+        MGPipeCanonicaliseSamplerParameters(clean, canonClean);
+        MGPipeCanonicaliseSamplerParameters(dirty, canonDirty);
+        EXPECT_EQ(MGPipeHashSamplerParameters(canonClean), MGPipeHashSamplerParameters(canonDirty));
+        // And the CONFIRM, not only the hash: the cache reuses a handle on a memcmp over these
+        // same canonical bytes, so the padding has to be deterministically zero in both.
+        EXPECT_EQ(std::memcmp(&canonClean, &canonDirty, sizeof(SamplerParameters)), 0);
+
+        Uint64 payload = 0;
+        const MGPipeHandle first = Cache().Acquire(clean, payload);
+        const MGPipeHandle second = Cache().Acquire(dirty, payload);
+        EXPECT_EQ(first, second) << "uninitialised padding must not mint a second CSO";
+        EXPECT_EQ(Cache().GetCounters().Mints, 1u);
+        EXPECT_EQ(Cache().GetCounters().Hits, 1u);
+    }
+
+    TEST(SamplerEmit, TwoIdenticalSamplersShareOneCso) {
+        EmitterScope scope;
+        Uint64 payload = 0;
+        const SamplerParameters params = DistinctParameters();
+        const MGPipeHandle a = Cache().Acquire(params, payload);
+        const MGPipeHandle b = Cache().Acquire(params, payload);
+        EXPECT_FALSE(MGPipeHandleIsNull(a));
+        EXPECT_EQ(a, b);
+        EXPECT_EQ(Cache().Size(), 1u);
+        EXPECT_EQ(Cache().GetCounters().Mints, 1u);
+        // A SamplerObject is a pure value with no driver-side per-object binding state, so two
+        // identical samplers really can share one CSO and one server-side twin. That is what
+        // makes content addressing right for this kind and wrong for vertex elements.
+        EXPECT_GT(payload, 0u);
+    }
+
+    TEST(SamplerEmit, ABorderColorFormChangeAloneMintsANewCso) {
+        EmitterScope scope;
+        Uint64 payload = 0;
+        SamplerParameters params = DistinctParameters();
+        const MGPipeHandle asInt = Cache().Acquire(params, payload);
+        params.borderColorForm = BorderColorForm::Uint;
+        const MGPipeHandle asUint = Cache().Acquire(params, payload);
+        EXPECT_NE(asInt, asUint) << "the form is the only thing that says which driver entry "
+                                    "point applies; the three colour values did not move";
+        EXPECT_EQ(Cache().GetCounters().Mints, 2u);
+    }
+
+    // The memcmp confirm exists because a bare 64-bit equality would alias two DIFFERENT
+    // sampler states onto one CSO - silent wrong filtering with no gate that can see it.
+    //
+    // A GENUINE XXH64 COLLISION CANNOT BE MANUFACTURED, so this case drives the branch through
+    // the cache's forced-hash test seam instead. Without it the case could not go red for its
+    // own name: two states that differ by one float ULP have different hashes, the confirm is
+    // never consulted, and the memcmp branch, the Collisions counter and the probe's
+    // continuation past a rejected entry were all completely uncovered.
+    TEST(SamplerEmit, AHashCollisionDoesNotAliasTwoSamplerStates) {
+        EmitterScope scope;
+        Uint64 payload = 0;
+        SamplerParameters first = DistinctParameters();
+        SamplerParameters second = DistinctParameters();
+        second.maxLod = second.maxLod + 0.0009765625f; // one representable step, nothing else moves
+        ASSERT_NE(std::memcmp(&first, &second, sizeof(SamplerParameters)), 0);
+
+        // ONE hash for two different values, which is exactly what a collision is.
+        constexpr Uint64 kForcedHash = 0x0123456789ABCDEFull;
+        const MGPipeHandle a = Cache().AcquireWithForcedHashForTest(first, kForcedHash, payload);
+        const MGPipeHandle b = Cache().AcquireWithForcedHashForTest(second, kForcedHash, payload);
+        EXPECT_NE(a, b) << "reusing the handle would filter one state with the other's parameters";
+        EXPECT_EQ(Cache().GetCounters().Collisions, 1u) << "and the rejection is counted, not silent";
+        EXPECT_EQ(Cache().GetCounters().Mints, 2u);
+        EXPECT_EQ(Cache().Size(), 2u);
+
+        // AND THE PROBE KEEPS GOING PAST THE REJECTED ENTRY rather than stopping at the first
+        // hash match: the first value is still resident behind the colliding one, so asking for
+        // it again is a HIT and not a third mint. Stopping at the first match would mint a
+        // duplicate CSO for a value the cache already holds.
+        const MGPipeHandle again = Cache().AcquireWithForcedHashForTest(first, kForcedHash, payload);
+        EXPECT_EQ(again, a);
+        EXPECT_EQ(Cache().GetCounters().Mints, 2u);
+        EXPECT_EQ(Cache().GetCounters().Hits, 1u);
+
+        // The ordinary path, for completeness: two states that differ in ONE field never share
+        // a handle and never reach the confirm at all.
+        Cache().ResetForTest();
+        Cache().ResetCounters();
+        const MGPipeHandle plainFirst = Cache().Acquire(first, payload);
+        const MGPipeHandle plainSecond = Cache().Acquire(second, payload);
+        EXPECT_NE(plainFirst, plainSecond);
+        EXPECT_EQ(Cache().GetCounters().Collisions, 0u);
+    }
+
+    // ============================ D-F2: the sampler view ============================
+
+    TEST(SamplerEmit, AnUnchangedTextureReIssuesNothing) {
+        EmitterScope scope;
+        GLuint name = 0;
+        const SharedPtr<ITextureObject> texture = MakeCompleteTexture(name, 4);
+        ASSERT_TRUE(texture);
+        Uint64 payload = 0;
+        const MGPipeHandle handle = MGPipeSlots().Acquire(MGPipeKind::Texture, texture->GetLifetimeId());
+        const MGPipeHandle view = Emitter().AcquireSamplerView(*texture, handle, payload);
+        ASSERT_FALSE(MGPipeHandleIsNull(view));
+        EXPECT_EQ(Emitter().ViewCreateCount(), 1u);
+        // THE VERSION-FIRST SKIP: nothing moved, so nothing is hashed, copied or emitted.
+        EXPECT_EQ(Emitter().AcquireSamplerView(*texture, handle, payload), view);
+        EXPECT_EQ(Emitter().ViewCreateCount(), 1u);
+    }
+
+    TEST(SamplerEmit, AViewIsReIssuedOnTheSameHandleWhenItsRestrictionsMove) {
+        EmitterScope scope;
+        namespace GL = MobileGL::MG_Impl::GLImpl;
+        GLuint name = 0;
+        const SharedPtr<ITextureObject> texture = MakeCompleteTexture(name, 4);
+        ASSERT_TRUE(texture);
+        Uint64 payload = 0;
+        const MGPipeHandle handle = MGPipeSlots().Acquire(MGPipeKind::Texture, texture->GetLifetimeId());
+        const MGPipeHandle view = Emitter().AcquireSamplerView(*texture, handle, payload);
+        ASSERT_FALSE(MGPipeHandleIsNull(view));
+        ASSERT_EQ(Emitter().ViewCreateCount(), 1u);
+        const Uint64 shapeBefore = texture->GetShapeVersion();
+
+        GL::BindTexture(GL_TEXTURE_2D, name);
+        GL::TexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, 8, 8, 0, GL_RGBA, GL_UNSIGNED_BYTE, nullptr);
+        ASSERT_NE(texture->GetShapeVersion(), shapeBefore) << "the storage really has to move";
+
+        // THE SAME HANDLE, a second record. Gen increments only on slot reuse and never on a
+        // respecify, so re-issuing on the same handle is legal and is what keeps a server's
+        // twin table from minting a second identity for one texture.
+        const MGPipeHandle reissued = Emitter().AcquireSamplerView(*texture, handle, payload);
+        EXPECT_EQ(reissued, view);
+        EXPECT_EQ(Emitter().ViewCreateCount(), 2u);
+        EXPECT_EQ(Emitter().LastCreatedView().Cso, view);
+        EXPECT_EQ(Emitter().LastCreatedView().Texture, handle);
+        EXPECT_EQ(Emitter().LastCreatedView().Target, static_cast<Uint8>(TextureTarget::Texture2D));
+        EXPECT_EQ(Emitter().LastCreatedView().InternalFormat, static_cast<Uint32>(texture->GetFormat()));
+        // An ordinary texture carries no view restriction, and zero is that statement rather
+        // than a second spelling of it: glTextureView always writes NumLevels >= 1.
+        EXPECT_EQ(Emitter().LastCreatedView().NumLevels, 0u);
+        EXPECT_EQ(Emitter().LastCreatedView().NumLayers, 0u);
+    }
+
+    // ============================ D-G: the two unit sets ============================
+
+    Uint MakeSamplerProgram() {
+        namespace GL = MobileGL::MG_Impl::GLImpl;
+        static const char* kVs = "#version 330 core\nvoid main(){ gl_Position = vec4(0.0); }\n";
+        static const char* kFs =
+            "#version 330 core\n"
+            "uniform sampler2D sampled;\n"
+            "out vec4 color;\n"
+            "void main(){ color = texture(sampled, vec2(0.0)); }\n";
+        const Uint program = GL::CreateProgram();
+        const Uint vs = GL::CreateShader(GL_VERTEX_SHADER);
+        GL::ShaderSource(vs, 1, &kVs, nullptr);
+        GL::CompileShader(vs);
+        GL::AttachShader(program, vs);
+        const Uint fs = GL::CreateShader(GL_FRAGMENT_SHADER);
+        GL::ShaderSource(fs, 1, &kFs, nullptr);
+        GL::CompileShader(fs);
+        GL::AttachShader(program, fs);
+        GL::LinkProgram(program);
+        return program;
+    }
+
+    // ARCHITECTURE's third merge rule: the client emits the PROGRAM-RESOLVED set. A unit the
+    // shader does not sample carries no view, whatever is bound to it - which is exactly the
+    // gallium one-view-per-slot resolved form, and exactly what DirectGLES arrives at by
+    // asking the program which of a unit's aliased bindings is the sampled one.
+    TEST(SamplerEmit, OnlyTheProgramResolvedUnitsAreEmitted) {
+        EmitterScope scope;
+        namespace GL = MobileGL::MG_Impl::GLImpl;
+        const Uint program = MakeSamplerProgram();
+        GLint linked = 0;
+        GL::GetProgramiv(program, GL_LINK_STATUS, &linked);
+        ASSERT_EQ(linked, GL_TRUE);
+        GL::UseProgram(program);
+        const GLint location = GL::GetUniformLocation(program, "sampled");
+        ASSERT_GE(location, 0);
+        GL::Uniform1i(location, 3);
+
+        GLuint sampledName = 0;
+        GLuint unsampledName = 0;
+        const SharedPtr<ITextureObject> sampled = MakeCompleteTexture(sampledName, 4);
+        const SharedPtr<ITextureObject> unsampled = MakeCompleteTexture(unsampledName, 4);
+        BindTextureToUnit(3, sampled);
+        BindTextureToUnit(5, unsampled);
+
+        ASSERT_GT(Emitter().EmitSamplerViews(Ctx()), 0u);
+        ASSERT_EQ(Emitter().ViewSetCount(), 1u);
+        ASSERT_GE(Emitter().LastSamplerViews().Count, 6u);
+        EXPECT_EQ(Emitter().LastSamplerViews().Start, 0u);
+
+        const MGPBoundView& resolved = Emitter().LastBoundViews()[3];
+        EXPECT_EQ(resolved.Unit, 3u);
+        EXPECT_FALSE(MGPipeHandleIsNull(resolved.Texture)) << "unit 3 is what the shader samples";
+        EXPECT_FALSE(MGPipeHandleIsNull(resolved.View));
+
+        const MGPBoundView& ignored = Emitter().LastBoundViews()[5];
+        EXPECT_EQ(ignored.Unit, 5u);
+        EXPECT_TRUE(MGPipeHandleIsNull(ignored.Texture))
+            << "unit 5 has a texture bound but no sampler uniform resolves to it";
+        EXPECT_TRUE(MGPipeHandleIsNull(ignored.View));
+
+        GL::UseProgram(0);
+    }
+
+    TEST(SamplerEmit, AnUnchangedSetEmitsNothing) {
+        EmitterScope scope;
+        GLuint name = 0;
+        const SharedPtr<ITextureObject> texture = MakeCompleteTexture(name, 4);
+        BindTextureToUnit(1, texture);
+        Emitter().EmitSamplerViews(Ctx());
+        const Uint64 after = Emitter().ViewSetCount();
+        // The suppressor's whole job: an unchanged resolved set is not sent again. Without it
+        // this would be a several-hundred-byte variable-length record per batch, because a
+        // redundant re-bind moves the bind generation and the dirty bit with it.
+        Emitter().EmitSamplerViews(Ctx());
+        EXPECT_EQ(Emitter().ViewSetCount(), after);
+    }
+
+    TEST(SamplerEmit, ARedundantRebindOfTheSameSamplerEmitsNothing) {
+        // THE SCOPE IS LOAD-BEARING and not decoration: without it this case's counter
+        // assertions would be reading whatever the previous case's destructor happened to
+        // leave, which is a suite-order dependence of exactly the class the padding bug was.
+        EmitterScope scope;
+        const SharedPtr<MG_State::GLState::SamplerObject>& sampler = Ctx().CreateSamplerObject(4131);
+        ASSERT_TRUE(sampler);
+        Ctx().GetTextureUnitObject(2).SetSamplerObject(sampler);
+        Ctx().NoteTextureUnitTouched(2);
+
+        ASSERT_GT(Emitter().EmitSamplerStates(Ctx()), 0u);
+        ASSERT_EQ(Emitter().StateSetCount(), 1u);
+        ASSERT_GE(Emitter().LastSamplerStates().Count, 3u);
+        EXPECT_FALSE(MGPipeHandleIsNull(Emitter().LastSamplerStateHandles()[2]));
+        EXPECT_TRUE(MGPipeHandleIsNull(Emitter().LastSamplerStateHandles()[0]))
+            << "a unit with no sampler object carries the null handle, and the texture's "
+               "built-in sampler then applies exactly as today";
+
+        // 26.2's idiom: the same sampler object re-bound at every texture-unit switch. The bind
+        // generation moves, so the dirty bit fires and this emitter runs - and emits nothing.
+        Ctx().BumpTextureBindGeneration();
+        Emitter().EmitSamplerStates(Ctx());
+        EXPECT_EQ(Emitter().StateSetCount(), 1u);
+        EXPECT_EQ(Cache().GetCounters().Mints, 1u) << "and it mints no second CSO either";
+
+        Ctx().GetTextureUnitObject(2).SetSamplerObject(SharedPtr<SamplerObject>());
+    }
+
+    // ==================== ID-17: the reference count on a cache entry ====================
+
+    // A BOUND SAMPLER STATE HOLDS A REFERENCE WHILE IT IS BOUND. The set the applier holds is
+    // "the last set as received" and outlives the pass that sent it, so a handle in it must not
+    // become the LRU's victim - nothing re-emits bind_sampler_states when a CSO is evicted,
+    // because an eviction is not a state change and no dirty bit fires for it.
+    //
+    // AND THE REFERENCE DOES NOT ACCUMULATE. Every Acquire takes one, and this emitter runs
+    // once per firing of the sampler bit - which 26.2 makes happen at every texture-unit
+    // switch - so an emitter that took a reference per pass and never gave one back would pin
+    // every CSO it ever bound for the life of the process.
+    TEST(SamplerEmit, ABoundSamplerStateHoldsItsCsoUntilTheUnitMoves) {
+        EmitterScope scope;
+        const SharedPtr<SamplerObject>& sampler = Ctx().CreateSamplerObject(4137);
+        ASSERT_TRUE(sampler);
+        Ctx().GetTextureUnitObject(2).SetSamplerObject(sampler);
+        Ctx().NoteTextureUnitTouched(2);
+
+        ASSERT_GT(Emitter().EmitSamplerStates(Ctx()), 0u);
+        const MGPipeHandle bound = Emitter().LastSamplerStateHandles()[2];
+        ASSERT_FALSE(MGPipeHandleIsNull(bound));
+        EXPECT_EQ(Cache().RefCountOf(bound), 1u) << "the applier's standing set names this handle";
+
+        Ctx().BumpTextureBindGeneration();
+        Emitter().EmitSamplerStates(Ctx());
+        EXPECT_EQ(Cache().RefCountOf(bound), 1u) << "one binding is one reference, not one per pass";
+
+        // The unit stops naming it, and the reference goes with the binding rather than with
+        // the entry: the value is still worth caching, it is merely evictable again.
+        Ctx().GetTextureUnitObject(2).SetSamplerObject(SharedPtr<SamplerObject>());
+        Emitter().EmitSamplerStates(Ctx());
+        EXPECT_TRUE(MGPipeHandleIsNull(Emitter().LastSamplerStateHandles()[2]));
+        EXPECT_EQ(Cache().RefCountOf(bound), 0u);
+        EXPECT_TRUE(Cache().RecordIsPublished(bound)) << "released is not evicted";
+    }
+
+    // THE FINDING ID-17 RULES ON. MGPTextureParams::BuiltinSampler names a sampler CSO out of
+    // this cache, the applier deliberately does NOT resolve that handle (an unresolvable one is
+    // an ordering fact, not a corrupt one), and set_texture_params is re-emitted only when a
+    // texture's parameters move - so an LRU eviction of a built-in sampler's entry would leave
+    // a published record naming a handle whose slot has been re-handed out to a different
+    // value, with nothing that refuses, counts, logs or re-emits. The capacity argument closes
+    // only the intra-pass case; the reference count is what closes this one.
+    TEST(SamplerEmit, AReferencedCsoIsNeverTheLruVictim) {
+        EmitterScope scope;
+        Uint64 payload = 0;
+        const SamplerParameters pinnedParams = DistinctParameters();
+        const MGPipeHandle pinned = Cache().Acquire(pinnedParams, payload);
+        ASSERT_FALSE(MGPipeHandleIsNull(pinned));
+        ASSERT_EQ(Cache().RefCountOf(pinned), 1u);
+
+        // A CTS sampler sweep, in miniature: twice the cache's capacity in distinct values,
+        // none of which anything keeps naming. The LRU has to run, hard.
+        SamplerParameters filler = DistinctParameters();
+        for (SizeT i = 0; i < kMGPipeSamplerCsoCacheCapacity * 2; ++i) {
+            filler.minLod = static_cast<float>(i) + 0.5f;
+            Cache().Release(Cache().Acquire(filler, payload));
+        }
+        ASSERT_GT(Cache().GetCounters().Evictions, 0u) << "the LRU really has to have run";
+        EXPECT_EQ(Cache().GetCounters().OverCapacityMints, 0u)
+            << "there were unreferenced entries to take, so nothing had to grow";
+
+        EXPECT_TRUE(Cache().RecordIsPublished(pinned))
+            << "a handle a standing record names is not the LRU's to take";
+        Uint64 second = 0;
+        EXPECT_EQ(Cache().Acquire(pinnedParams, second), pinned);
+        EXPECT_EQ(second, 0u) << "and it was a hit, not a re-mint under the same value";
+
+        Cache().Release(pinned);
+        Cache().Release(pinned);
+    }
+
+    // AND WHEN EVERY ENTRY IS PINNED THE CACHE GROWS AND SAYS SO. Growing is the safe
+    // direction - a slot too many costs memory, a handle pulled out from under a live record
+    // costs correctness - and OverCapacityMints is a RECORDED NUMBER rather than a gate, so a
+    // workload that pins more than the capacity is visible instead of being wrong.
+    TEST(SamplerEmit, AFullyPinnedCacheMintsBeyondItsCapacityAndCountsIt) {
+        EmitterScope scope;
+        Uint64 payload = 0;
+        SamplerParameters params = DistinctParameters();
+        Vector<MGPipeHandle> held;
+        for (SizeT i = 0; i < kMGPipeSamplerCsoCacheCapacity; ++i) {
+            params.minLod = static_cast<float>(i) + 0.5f;
+            held.push_back(Cache().Acquire(params, payload));
+        }
+        ASSERT_EQ(Cache().Size(), kMGPipeSamplerCsoCacheCapacity);
+        ASSERT_EQ(Cache().GetCounters().Evictions, 0u);
+        ASSERT_EQ(Cache().GetCounters().OverCapacityMints, 0u);
+
+        params.minLod = -12.5f; // one more distinct value, with nothing evictable
+        const MGPipeHandle extra = Cache().Acquire(params, payload);
+        EXPECT_FALSE(MGPipeHandleIsNull(extra));
+        EXPECT_EQ(Cache().Size(), kMGPipeSamplerCsoCacheCapacity + 1);
+        EXPECT_EQ(Cache().GetCounters().Evictions, 0u) << "no pinned entry may be taken";
+        EXPECT_EQ(Cache().GetCounters().OverCapacityMints, 1u) << "and the growth is counted";
+
+        for (const MGPipeHandle& handle : held) {
+            EXPECT_TRUE(Cache().RecordIsPublished(handle));
+            Cache().Release(handle);
+        }
+        Cache().Release(extra);
+    }
+
+    // THE COUNT IS PER HANDLE, NOT PER HOLDER, and this is what makes that visible to whoever
+    // holds one. Entries are content-addressed and shared by design - package B's texture-params
+    // record and this file's own bind_sampler_states name the SAME handle when the values match,
+    // each owing exactly one Release - so a holder that releases twice takes the OTHER holder's
+    // pin and the LRU may then evict a handle a published record still names, with nothing to
+    // refuse and nothing to re-emit. The cache cannot repair that, so it counts it; an assert
+    // could not, because MOBILEGL_ASSERT compiles out at INFO, i.e. in every build that runs.
+    TEST(SamplerEmit, AReleaseThisCacheNeverHandedOutIsCountedRatherThanAbsorbed) {
+        EmitterScope scope;
+        Uint64 payload = 0;
+        const SamplerParameters params = DistinctParameters();
+        const MGPipeHandle cso = Cache().Acquire(params, payload);
+        ASSERT_FALSE(MGPipeHandleIsNull(cso));
+        ASSERT_EQ(Cache().RefCountOf(cso), 1u);
+        ASSERT_EQ(Cache().GetCounters().UnknownReleases, 0u);
+        ASSERT_EQ(Cache().GetCounters().UnderflowedReleases, 0u);
+
+        // A HANDLE THIS CACHE NEVER MINTED: a stale one from before a reset, or one of another
+        // kind passed by mistake. It falls off the end of the probe and used to leave no trace
+        // at all - Releases counts only releases that found an entry.
+        Cache().Release(MGPipeHandle{cso.Slot + 4096u, cso.Gen});
+        EXPECT_EQ(Cache().GetCounters().UnknownReleases, 1u);
+        EXPECT_EQ(Cache().RefCountOf(cso), 1u) << "and it took nobody else's pin on the way";
+
+        // A SECOND RELEASE OF A REFERENCE ONLY ONE HOLDER OWED. The count does not underflow -
+        // that half was already right - but the attempt is now named.
+        Cache().Release(cso);
+        EXPECT_EQ(Cache().RefCountOf(cso), 0u);
+        EXPECT_EQ(Cache().GetCounters().UnderflowedReleases, 0u);
+        Cache().Release(cso);
+        EXPECT_EQ(Cache().RefCountOf(cso), 0u) << "no underflow";
+        EXPECT_EQ(Cache().GetCounters().UnderflowedReleases, 1u);
+
+        // A NULL HANDLE IS NEITHER: an out-of-window unit holds one and releasing it is the
+        // ordinary no-op the reconciliation depends on.
+        const auto before = Cache().GetCounters();
+        Cache().Release(kMGPipeNullHandle);
+        EXPECT_EQ(Cache().GetCounters().UnknownReleases, before.UnknownReleases);
+        EXPECT_EQ(Cache().GetCounters().Releases, before.Releases);
+        // NOTHING WAS EVICTED WHILE REFERENCED, which is the ID-17 invariant the same round
+        // turned from a compiled-out assert into a number.
+        EXPECT_EQ(Cache().GetCounters().ReferencedEvictions, 0u);
+    }
+} // namespace
+#endif // MOBILEGL_PIPE_PUSH
+
 int main(int argc, char** argv) {
     namespace fs = std::filesystem;
     const fs::path path =
@@ -535,6 +1102,11 @@ int main(int argc, char** argv) {
     _putenv_s("MOBILEGL_LOG_FILE_PATH", g_logPath.c_str());
 #else
     setenv("MOBILEGL_LOG_FILE_PATH", g_logPath.c_str(), 1);
+#endif
+#if MOBILEGL_PIPE_PUSH
+    // ONE process-wide context for the whole suite, because half these cases need a really
+    // linked program and glslang lives behind this call. Each case uses GL names of its own.
+    MobileGL::Initialize();
 #endif
     ::testing::InitGoogleTest(&argc, argv);
     const int rc = RUN_ALL_TESTS();

MobileGL/MG_Test/Pipe/TrackerTest.cpp

@@ -80,6 +80,11 @@ namespace {
     X(TrackerWalk, ARestagedProgramPipelineFiresTheProgramBits) \
     X(TrackerWalk, ARelinkOfAStageProgramFiresTheProgramBits) \
     X(TrackerWalk, UseProgramZeroLeavesTheBoundPipelineDrivingTheProgramBits) \
+    X(TrackerAggregates, ATextureStorageDefinitionMovesTheFramebufferAggregateToo) \
+    X(TrackerAggregates, ARenderbufferStorageDefinitionMovesTheFramebufferAggregate) \
+    X(TrackerWalk, AProgramSwitchAloneFiresTheSamplerViewBit) \
+    X(TrackerWalk, ATextureParameterAloneFiresTheSamplerViewBit) \
+    X(TrackerWalk, AProgramSwitchBetweenEqualImageUnitCountersFiresTheShaderImageBit) \
     X(TrackerAttribPayload, AFloatWriteCarriesTheFloatBitsAndNamesItsClass) \
     X(TrackerAttribPayload, AnIntWriteCarriesTheIntWordsAndNamesItsClass) \
     X(TrackerAttribPayload, AUintWriteCarriesTheUintWordsAndNamesItsClass) \
@@ -232,6 +237,39 @@ namespace {
         SUCCEED();
     }
 
+    // P4a FABLE SEAM F-3. set_framebuffer_state INLINES an attachment's format, extent and
+    // samples (D-C1), so the setters that define a texture's storage are setters of a
+    // framebuffer-record field - and the record-field -> setter -> shutter rule (Tracker.h's
+    // table) says they must move the aggregate bit 11 reads. They still move the params
+    // aggregate they always moved; what this case pins is the SECOND bump, which the
+    // "moves only" cases above cannot see and which is the whole of F-3's fix.
+    TEST_F(TrackerAggregates, ATextureStorageDefinitionMovesTheFramebufferAggregateToo) {
+        const auto& tex = Ctx().CreateTextureObject(3, TextureTarget::Texture2D);
+        ASSERT_TRUE(tex != nullptr);
+        const Snapshot before = Snap();
+        tex->SetInternalFormat(MobileGL::TextureInternalFormat::RGBA8);
+        const Snapshot after = Snap();
+        EXPECT_GT(after[MGPipeAggregate::FramebufferAttachment], before[MGPipeAggregate::FramebufferAttachment])
+            << "a texture whose storage is redefined WHILE ATTACHED left set_framebuffer_state "
+               "describing the previous format (F-3)";
+        EXPECT_GT(after[MGPipeAggregate::TextureParams], before[MGPipeAggregate::TextureParams]);
+        EXPECT_EQ(after[MGPipeAggregate::TextureContent], before[MGPipeAggregate::TextureContent]);
+        EXPECT_EQ(after[MGPipeAggregate::VaoAttribute], before[MGPipeAggregate::VaoAttribute]);
+        EXPECT_EQ(after[MGPipeAggregate::BufferChange], before[MGPipeAggregate::BufferChange]);
+        EXPECT_EQ(after[MGPipeAggregate::VertexAttribDefault], before[MGPipeAggregate::VertexAttribDefault]);
+    }
+
+    // The renderbuffer twin, and the one that had NO aggregate at all before: its three storage
+    // setters bumped no version and raised no notice (D-D2 closed the resource record by emitting
+    // from the entry point and left the framebuffer record stale).
+    TEST_F(TrackerAggregates, ARenderbufferStorageDefinitionMovesTheFramebufferAggregate) {
+        const auto& rbo = Ctx().CreateRenderbufferObject(1);
+        ASSERT_TRUE(rbo != nullptr);
+        const Snapshot before = Snap();
+        rbo->AllocateStorage(IntVec2{8, 8});
+        ExpectOnly(MGPipeAggregate::FramebufferAttachment, before, Snap());
+    }
+
     // ===================================================================================
     // The dirty walk itself, and the render-state emission it drives (P2 brief D4, D6, D7)
     // ===================================================================================
@@ -751,6 +789,68 @@ namespace {
         EXPECT_NE(dirty & MGPipeDirtyBit(MGPipeDirty::NewGlobalConstants), 0u);
     }
 
+    // P4a FABLE SEAM F-1. set_sampler_views is resolved for the PROGRAM IN USE (the sampler
+    // uniform's type picks which of a unit's targets is the view), and bit 12's shutter read
+    // only the texture-content aggregate and the bind generation - so `glUseProgram(P1); draw;
+    // glUseProgram(P2); draw` never re-emitted the set and the record went on describing P1's
+    // units. A program switch alone, with no bind and no texture change, has to fire it.
+    TEST_F(TrackerWalk, AProgramSwitchAloneFiresTheSamplerViewBit) {
+        const Uint first = Ctx().CreateProgram();
+        const Uint second = Ctx().CreateProgram();
+        Ctx().UseProgram(first);
+        Walk();
+        ASSERT_EQ(Walk(), 0u) << "the fixture did not reach a steady state";
+
+        Ctx().UseProgram(second);
+        const Uint32 dirty = Walk();
+        EXPECT_NE(dirty & MGPipeDirtyBit(MGPipeDirty::NewSamplerViews), 0u)
+            << "the view set is resolved for the program in use and a glUseProgram alone did not "
+               "re-emit it (F-1)";
+        EXPECT_EQ(Walk(), 0u) << "the widened shutter fires forever";
+    }
+
+    // The other input F-1 added: the params aggregate. SamplerEmit.h drops a unit's view to
+    // null when SamplesAsIncompleteTexture says so, and that predicate reads the effective
+    // sampler's filters and the level range - a glTexParameteri that completes a texture fired
+    // bit 13 and left the view entry null.
+    TEST_F(TrackerWalk, ATextureParameterAloneFiresTheSamplerViewBit) {
+        const auto& tex = Ctx().CreateTextureObject(1, TextureTarget::Texture2D);
+        ASSERT_TRUE(tex != nullptr);
+        Walk();
+        ASSERT_EQ(Walk(), 0u) << "the fixture did not reach a steady state";
+
+        tex->SetMaxLevel(4);
+        const Uint32 dirty = Walk();
+        EXPECT_NE(dirty & MGPipeDirtyBit(MGPipeDirty::NewSamplerViews), 0u)
+            << "completeness is a view-set input and a parameter change did not re-resolve it";
+        EXPECT_NE(dirty & MGPipeDirtyBit(MGPipeDirty::NewSamplers), 0u);
+        EXPECT_EQ(Walk(), 0u);
+    }
+
+    // P4a FABLE SEAM F-2 (and E's SD-4, which is this bit through a buffer image). Bit 14's
+    // plain-program arm mixed GetImageUnitVersion() ALONE - a per-program counter that two
+    // programs routinely share, 0 == 0 for any pair that never moved an image unit through
+    // glUniform1i - so a glUseProgram between them fired nothing and set_shader_images' window
+    // stayed the previous program's. The pipeline arm already mixed stageLinks; the plain arm
+    // now mixes the same identity bit 6 reads.
+    TEST_F(TrackerWalk, AProgramSwitchBetweenEqualImageUnitCountersFiresTheShaderImageBit) {
+        const Uint first = Ctx().CreateProgram();
+        const Uint second = Ctx().CreateProgram();
+        ASSERT_EQ(Ctx().GetProgramObject(first)->GetImageUnitVersion(),
+                  Ctx().GetProgramObject(second)->GetImageUnitVersion())
+            << "the premise of this case is two programs whose image-unit counters are equal";
+        Ctx().UseProgram(first);
+        Walk();
+        ASSERT_EQ(Walk(), 0u) << "the fixture did not reach a steady state";
+
+        Ctx().UseProgram(second);
+        const Uint32 dirty = Walk();
+        EXPECT_NE(dirty & MGPipeDirtyBit(MGPipeDirty::NewShaderImages), 0u)
+            << "set_shader_images' window is the program's and a glUseProgram alone did not "
+               "re-emit it (F-2)";
+        EXPECT_EQ(Walk(), 0u) << "the widened shutter fires forever";
+    }
+
     // ===================================================================================
     // set_vertex_attrib_defaults' payload (P2 brief D10)
     // ===================================================================================

MobileGL/MG_Test/SanityTest.cpp

@@ -3129,6 +3129,177 @@ TEST(DirectGLESTextureSync, UnitMemoRefusesToDriveATwinFromAnotherTexture) {
     MG_Impl::GLImpl::BindTexture(GL_TEXTURE_2D, 0);
 }
 
+namespace {
+    // What glTexParameteri actually reached the driver, and which backend texture was bound
+    // when it did. The G9 probe below is a WHITE-BOX assertion (ID-19): the parameter push is
+    // not observable through public GL without creating the very sampler view whose absence is
+    // the subject, so the observation is taken at the driver boundary instead.
+    struct TexParamCall {
+        GLuint texture;
+        GLenum pname;
+        GLint value;
+    };
+    MobileGL::Vector<TexParamCall>* g_texParamCalls = nullptr;
+    GLuint g_texParamBoundTexture = 0;
+
+    void TP_BindTexture(GLenum, GLuint texture) { g_texParamBoundTexture = texture; }
+    void TP_ActiveTexture(GLenum) {}
+    void TP_TexParameteri(GLenum, GLenum pname, GLint value) {
+        if (g_texParamCalls) {
+            g_texParamCalls->push_back({g_texParamBoundTexture, pname, value});
+        }
+    }
+    void TP_TexParameterf(GLenum, GLenum, GLfloat) {}
+    void TP_TexParameterfv(GLenum, GLenum, const GLfloat*) {}
+    void TP_PixelStorei(GLenum, GLint) {}
+    void TP_BindBuffer(GLenum, GLuint) {}
+
+    struct ScopedTexParamRecording {
+        explicit ScopedTexParamRecording(MobileGL::Vector<TexParamCall>& sink) {
+            g_texParamCalls = &sink;
+            g_texParamBoundTexture = 0;
+        }
+        ~ScopedTexParamRecording() { g_texParamCalls = nullptr; }
+        ScopedTexParamRecording(const ScopedTexParamRecording&) = delete;
+        ScopedTexParamRecording& operator=(const ScopedTexParamRecording&) = delete;
+    };
+} // namespace
+
+// G9 AS A WHITE-BOX ASSERTION (gates review R1, ID-19), AND IT COVERS THE HALF THE PUBLIC-GL
+// SCENARIO CANNOT.
+//
+// TextureParamsWithoutASamplerViewScenario catches "the parameters were EMITTED and marked
+// synced but never applied": its observation is a sample, the sample creates the sampler view,
+// and IsDrawSyncClean then skips the sync. What it cannot catch is a backend that merely DEFERS
+// the apply to the first sampler view - the observation creates that view, the parameters land
+// at that moment, and the case is green. Here the reading is taken while the texture is still
+// attachment-only: nothing is ever bound to a unit, no sampler view is minted, and the
+// assertion is that the parameter reached the driver ANYWAY.
+//
+// RED ON THE PRE-P4a BEHAVIOUR: with set_texture_params addressed by resource, this twin's
+// parameter push no longer needs anything to be bound. A backend that reinstated the deferral -
+// resolving the params through a sampler view, or gating the push on a unit binding - leaves
+// the recording empty and this case fails, which is exactly the regression the scenario's
+// self-repair hides.
+//
+// WHAT IT DOES NOT COVER, AND THE NEXT READER MUST NOT OVER-TRUST IT (review N-9): the probe
+// drives SyncTextureParamsToBackend DIRECTLY, so the only deferral shape it can see is one
+// INSIDE that function. A regression that gates the CALL on a sampler view existing - in
+// SyncNeccessaryTextures, or in package E's per-unit walk - leaves this case green. That
+// caller-level half is a scenario's job and the scenario is package F's (G9's scenario half,
+// gates review R1); this is the backend-side probe R1 asked for and nothing wider.
+TEST(DirectGLESTextureSync, AnAttachmentOnlyTexturesParametersReachTheDriverWithNoSamplerView) {
+    using namespace MobileGL;
+    ScopedDirectGLESTextureBindings scoped; // fresh GLContext + registry + binding caches
+    Vector<TexParamCall> params;
+    ScopedTexParamRecording recording(params);
+
+    auto functions = MG_Backend::DirectGLES::g_GLESFuncs;
+    functions.glBindTexture = TP_BindTexture;
+    functions.glActiveTexture = TP_ActiveTexture;
+    functions.glTexParameteri = TP_TexParameteri;
+    functions.glTexParameterf = TP_TexParameterf;
+    functions.glTexParameterfv = TP_TexParameterfv;
+    functions.glPixelStorei = TP_PixelStorei;
+    functions.glBindBuffer = TP_BindBuffer;
+    MG_Backend::DirectGLES::SetGLESFuncsTable(functions);
+
+    GLuint name = 0;
+    MG_Impl::GLImpl::GenTextures(1, &name);
+    const auto texture = MakeComplete2DTexture(name, 8);
+    ASSERT_NE(texture, nullptr);
+    // ATTACHMENT-ONLY from here on: the unit that specified it is released, so nothing in this
+    // test ever binds this texture for sampling and nothing mints a sampler view for it.
+    MG_Impl::GLImpl::BindTexture(GL_TEXTURE_2D, 0);
+
+    // The parameter that has to travel. Red -> Green is not any texture's default, so a driver
+    // that never hears about it is distinguishable from one that does.
+    texture->SetSwizzleParam(TextureSwizzleParam::Red, TextureSwizzleParam::Green);
+
+    auto& registry = MG_Backend::DirectGLES::TextureImpl::g_backendTextureObjects;
+    auto& twin = registry.GetOrCreate(texture);
+    if (!twin) {
+        twin = MakeShared<MG_Backend::DirectGLES::TextureImpl::BackendTextureObject>();
+    }
+    ASSERT_NE(twin, nullptr);
+
+#if MOBILEGL_PIPE_PUSH
+    const MG_Pipe::MGPipeHandle res = registry.HandleOf(texture.get());
+    MG_Pipe::MGPipeHandle builtinSampler = MG_Pipe::kMGPipeNullHandle;
+    if (MG_Backend::DirectGLES::TextureResourceSubsystemEnabled()) {
+        // The handle arm reads the applier, so the applier is what this probe writes - which is
+        // also what makes it a white-box test rather than a scenario: no client emitter exists
+        // on this tree, and the point is Espryt's behaviour given a record, not the client's.
+        ASSERT_FALSE(MG_Pipe::MGPipeHandleIsNull(res));
+        MG_Pipe::MGPResourceDesc desc{};
+        desc.Resource = res;
+        desc.Target = static_cast<Uint8>(MG_Pipe::MGPipeResourceTarget::Tex2D);
+        desc.StorageKind = static_cast<Uint8>(TextureStorageType::Mipmap);
+        desc.InternalFormat = static_cast<Uint32>(TextureInternalFormat::RGBA8);
+        desc.Width = 8;
+        desc.Height = 8;
+        desc.Depth = 1;
+        desc.ArrayLayers = 1;
+        desc.Levels = 1;
+        EXPECT_TRUE(MG_Pipe::MGPipeApplyResourceCreate(desc));
+
+        // Every ITextureObject owns a sampler object, so the built-in sampler CSO is not
+        // optional (a null one is Fatal{ProtocolCorruption} in the applier). It is a SAMPLER
+        // CSO and not a sampler VIEW - the distinction this case exists for.
+        auto samplerOwner = MakeShared<MG_State::GLState::SamplerObject>(0u);
+        builtinSampler = MG_Pipe::MGPipeSlots().Acquire(MG_Pipe::MGPipeKind::SamplerCso,
+                                                        samplerOwner->GetLifetimeId());
+        ASSERT_FALSE(MG_Pipe::MGPipeHandleIsNull(builtinSampler));
+        MG_Pipe::MGPSamplerDesc samplerDesc{};
+        samplerDesc.Cso = builtinSampler;
+        SamplerParameters samplerParams{};
+        MG_Pipe::MGPipeApplyCreateSamplerState(samplerDesc, &samplerParams);
+
+        MG_Pipe::MGPTextureParams pushed{};
+        pushed.Res = res;
+        pushed.BuiltinSampler = builtinSampler;
+        pushed.MaxLevel = 0;
+        pushed.Swizzle[0] = static_cast<Uint8>(TextureSwizzleParam::Green);
+        pushed.Swizzle[1] = static_cast<Uint8>(TextureSwizzleParam::Green);
+        pushed.Swizzle[2] = static_cast<Uint8>(TextureSwizzleParam::Blue);
+        pushed.Swizzle[3] = static_cast<Uint8>(TextureSwizzleParam::Alpha);
+        MG_Pipe::MGPipeApplySetTextureParams(pushed);
+
+        // THE OBSERVATION IS TAKEN WHILE THE TEXTURE IS STILL ATTACHMENT-ONLY: no sampler view
+        // record exists, and no sampler-view twin does either. This is the assertion the public
+        // scenario cannot make, because making it there would create the view.
+        EXPECT_EQ(MG_Backend::DirectGLES::SamplerViewImpl::g_backendSamplerViews.FindByHandle(
+                      MG_Pipe::MGPipeSlots().FindByLifetimeId(MG_Pipe::MGPipeKind::SamplerViewCso,
+                                                              texture->GetLifetimeId())),
+                  nullptr)
+            << "a sampler view was minted for a texture nothing sampled";
+    }
+#endif
+
+    const SizeT before = params.size();
+    twin->SyncTextureParamsToBackend(texture);
+
+    Bool sawSwizzleR = false;
+    for (SizeT i = before; i < params.size(); ++i) {
+        if (params[i].pname == GL_TEXTURE_SWIZZLE_R) {
+            sawSwizzleR = true;
+            EXPECT_EQ(params[i].value, static_cast<GLint>(GL_GREEN))
+                << "the swizzle reached the driver with the wrong value";
+        }
+    }
+    EXPECT_TRUE(sawSwizzleR)
+        << "an attachment-only texture's GL_TEXTURE_SWIZZLE_R never reached the driver: the "
+           "parameter push is gated on something being bound, which is the deferral G9's public "
+           "scenario cannot observe";
+
+#if MOBILEGL_PIPE_PUSH
+    if (!MG_Pipe::MGPipeHandleIsNull(builtinSampler)) {
+        MG_Pipe::MGPipeApplyDeleteSamplerState(MG_Pipe::MGPHandleOnly{builtinSampler});
+        MG_Pipe::MGPipeSlots().Free(MG_Pipe::MGPipeKind::SamplerCso, builtinSampler);
+    }
+#endif
+}
+
 TEST(DirectVulkanSanity, GraphicsSamplerFeedbackOnlyAliasesWritableOverlappingMip) {
     using MobileGL::MG_Backend::DirectVulkan::UniformManager;
 
@@ -3954,6 +4125,238 @@ TEST(DirectGLESSlotTable, EverySwitchedOverKindResolvesItsTwinThroughTheHandleAr
         table.ReleaseByHandle(second);
         MG_Pipe::MGPipeSlots().Free(MG_Pipe::MGPipeKind::Buffer, second);
     }
+
+    // P4a: the EIGHTH table and the SIXTH kind - the sampler view, which is the only kind in
+    // the phase with no frontend object at all. MobileGL has no sampler-view class: GL binds a
+    // texture to a unit and the sampler uniform's type plus the two completeness predicates
+    // decide what the shader sees, gallium's one-view-per-slot IS that resolved form, and the
+    // resolution moves to the CLIENT (D-F3). So this table is handle-keyed only, like the
+    // buffer resource table above, and its twin owns no driver id whatsoever - what it holds is
+    // the server's memo of one resolved view plus the raw-depth-fetch substitution decision,
+    // which is one of the two backend post-processings ARCHITECTURE.md:206 keeps on the server.
+    //
+    // The handle is minted off the TEXTURE's lifetime id (D-F2: one view per ITextureObject),
+    // which is what makes HandleOf resolve at all - and it is legal precisely because the two
+    // kinds have separate slot spaces, so the same lifetime id names a Texture slot and a
+    // SamplerViewCso slot without either shadowing the other.
+    {
+        using MobileGL::MG_Backend::DirectGLES::SamplerViewImpl::g_backendSamplerViews;
+        using MobileGL::MG_Backend::DirectGLES::SamplerViewImpl::BackendSamplerViewObject;
+        auto& table = g_backendSamplerViews;
+
+        SharedPtr<ITextureObject> owner = MakeShared<TextureObject2D>(0u);
+        const MG_Pipe::MGPipeHandle first =
+            MG_Pipe::MGPipeSlots().Acquire(MG_Pipe::MGPipeKind::SamplerViewCso, owner->GetLifetimeId());
+        ASSERT_FALSE(MG_Pipe::MGPipeHandleIsNull(first))
+            << "SamplerViewCso: the client allocator minted no handle for a live texture's view";
+
+        // The same lifetime id, two kinds, two independent slot spaces.
+        const MG_Pipe::MGPipeHandle textureHandle =
+            MG_Pipe::MGPipeSlots().FindByLifetimeId(MG_Pipe::MGPipeKind::Texture, owner->GetLifetimeId());
+        EXPECT_FALSE(first == textureHandle)
+            << "SamplerViewCso: the view handle and the texture handle are the same {slot, gen}, so "
+               "one kind's slot space is aliasing the other's";
+
+        auto& firstTwin = table.GetOrCreate(first);
+        firstTwin = MakeShared<BackendSamplerViewObject>();
+        firstTwin->SyncedSerial = 0xABCDEFull;
+        const BackendSamplerViewObject* const firstRaw = firstTwin.get();
+        EXPECT_EQ(table.FindByHandle(first), &firstTwin)
+            << "SamplerViewCso: the handle does not address the twin GetOrCreate handed back";
+        EXPECT_EQ(table.HandleOf(owner.get()), first)
+            << "SamplerViewCso: HandleOf did not resolve the view minted off this texture's "
+               "lifetime id, so a backend path that still arrives holding the object cannot find "
+               "its view";
+
+        const SharedPtr<BackendSamplerViewObject> released = table.ReleaseByHandle(first);
+        EXPECT_NE(released, nullptr) << "SamplerViewCso: delete_sampler_view found no twin to retire";
+        EXPECT_EQ(table.FindByHandle(first), nullptr)
+            << "SamplerViewCso: the twin outlived its delete_sampler_view";
+        MG_Pipe::MGPipeSlots().Free(MG_Pipe::MGPipeKind::SamplerViewCso, first);
+
+        auto successorOwner = MakeShared<TextureObject2D>(0u);
+        const MG_Pipe::MGPipeHandle second = MG_Pipe::MGPipeSlots().Acquire(
+            MG_Pipe::MGPipeKind::SamplerViewCso, successorOwner->GetLifetimeId());
+        ASSERT_FALSE(MG_Pipe::MGPipeHandleIsNull(second)) << "SamplerViewCso";
+        EXPECT_EQ(second.Slot, first.Slot)
+            << "SamplerViewCso: the freed slot was not handed back, so this walk did not exercise "
+               "the recycle it exists to test";
+        EXPECT_NE(second.Gen, first.Gen)
+            << "SamplerViewCso: Gen did not move on slot reuse - the predecessor's handle would "
+               "resolve to the successor's view, which is the ABA the {slot, gen} key exists to stop";
+        EXPECT_EQ(table.FindByHandle(first), nullptr) << "SamplerViewCso: the STALE handle resolved";
+
+        auto& secondTwin = table.GetOrCreate(second);
+        EXPECT_EQ(secondTwin, nullptr)
+            << "SamplerViewCso: a view at a recycled slot inherited its predecessor's memo, so the "
+               "raw-depth-fetch decision of a dead texture would be replayed for a live one";
+        secondTwin = MakeShared<BackendSamplerViewObject>();
+        EXPECT_NE(table.FindByHandle(second)->get(), firstRaw) << "SamplerViewCso";
+
+        // BACKWARD generations are REFUSED rather than adopted, exactly as they are on every
+        // other handle-keyed table (SlotTables.h:301-321). Forward is a recycle; adopting a
+        // backward one would retire the incumbent LIVE twin and then stamp the slot back to the
+        // dead view's generation.
+        //
+        // m-8: THE FIRST ASSERTION BELOW CANNOT DISTINGUISH THE TWO OUTCOMES and its message
+        // must not claim it does. GetOrCreate(handle) calls entry.backend.reset() before it
+        // stamps, so an ADOPTED backward generation yields a null BackendPtr& just as a refused
+        // one does. What separates refusal from adoption is the SECOND assertion: after an
+        // adoption the live twin at `second` is gone. The first is kept because a non-null there
+        // would mean the table handed back the incumbent's own twin under the dead handle, which
+        // is a third outcome and a worse one.
+        auto& stale = table.GetOrCreate(first);
+        EXPECT_EQ(stale, nullptr)
+            << "SamplerViewCso: a stale handle was answered with the LIVE twin at its slot (this "
+               "assertion cannot tell a refusal from an adoption - the next one does)";
+        EXPECT_NE(table.FindByHandle(second), nullptr)
+            << "SamplerViewCso: the live twin was destroyed by a handle from its slot's past - "
+               "the backward generation was ADOPTED rather than refused";
+
+        table.ReleaseByHandle(second);
+        MG_Pipe::MGPipeSlots().Free(MG_Pipe::MGPipeKind::SamplerViewCso, second);
+    }
+}
+
+// P4a (ID-8): the backend death notice is the REDUNDANT SECOND PATH for every kind the client
+// mints, and it must be IDEMPOTENT - the client's own helper emits the wire delete, raises this
+// notice and frees the slot, in that order, so whichever of the two frees first wins and the
+// other must find nothing and do nothing.
+//
+// Driven through the REAL consumer the backend installed rather than through a recording stub:
+// what is under test is Espryt's OnFrontendStateObjectDestroyed arm, including the SamplerViewCso
+// arm P4a adds, and a stub would prove only that the test can call itself.
+TEST(DirectGLESSlotTable, ADeathNoticeForEveryP4aKindIsIdempotent) {
+    using namespace MobileGL;
+    using namespace MobileGL::MG_Backend::DirectGLES;
+    using namespace MobileGL::MG_State::GLState;
+
+    if (!EsprytSlotTablesEnabled()) {
+        GTEST_SKIP() << "the legacy arm keys twins on the frontend heap address and cannot answer "
+                        "a death notice at all";
+    }
+
+    const MG_State::GLState::StateObjectDeathOps* ops = MG_State::GLState::GetStateObjectDeathOps();
+    ASSERT_NE(ops, nullptr) << "the backend installed no death-notice consumer";
+    ASSERT_NE(ops->OnDestroyed, nullptr);
+
+    // The sampler view first, because it is the arm P4a adds and the only kind whose notice
+    // names a lifetime id belonging to ANOTHER object (the texture the view was minted off).
+    {
+        using SamplerViewImpl::BackendSamplerViewObject;
+        using SamplerViewImpl::g_backendSamplerViews;
+
+        auto owner = MakeShared<TextureObject2D>(0u);
+        const Uint64 lifetimeId = owner->GetLifetimeId();
+        const MG_Pipe::MGPipeHandle view =
+            MG_Pipe::MGPipeSlots().Acquire(MG_Pipe::MGPipeKind::SamplerViewCso, lifetimeId);
+        ASSERT_FALSE(MG_Pipe::MGPipeHandleIsNull(view));
+        g_backendSamplerViews.GetOrCreate(view) = MakeShared<BackendSamplerViewObject>();
+        ASSERT_NE(g_backendSamplerViews.FindByHandle(view), nullptr);
+
+        ops->OnDestroyed(MG_Pipe::MGPipeKind::SamplerViewCso, lifetimeId);
+        EXPECT_EQ(g_backendSamplerViews.FindByHandle(view), nullptr)
+            << "the sampler-view notice left the twin behind, so the slot's next owner would "
+               "inherit a dead texture's resolved view";
+        EXPECT_TRUE(MG_Pipe::MGPipeHandleIsNull(
+            MG_Pipe::MGPipeSlots().FindByLifetimeId(MG_Pipe::MGPipeKind::SamplerViewCso, lifetimeId)))
+            << "the notice did not return the slot";
+
+        // The second path. The client's helper calls Free right after raising the notice, and a
+        // Free on a slot that is no longer live at that generation is a proven no-op
+        // (SlotAllocator.cpp:117-119) - so this is the shape that actually ships, twice over.
+        ops->OnDestroyed(MG_Pipe::MGPipeKind::SamplerViewCso, lifetimeId);
+        MG_Pipe::MGPipeSlots().Free(MG_Pipe::MGPipeKind::SamplerViewCso, view);
+        ops->OnDestroyed(MG_Pipe::MGPipeKind::SamplerViewCso, lifetimeId);
+        EXPECT_EQ(g_backendSamplerViews.FindByHandle(view), nullptr);
+
+        // And the slot really is back: a successor gets it with a moved generation, which is
+        // the property a double free would break by skipping one.
+        auto successor = MakeShared<TextureObject2D>(0u);
+        const MG_Pipe::MGPipeHandle reused = MG_Pipe::MGPipeSlots().Acquire(
+            MG_Pipe::MGPipeKind::SamplerViewCso, successor->GetLifetimeId());
+        EXPECT_EQ(reused.Slot, view.Slot);
+        EXPECT_NE(reused.Gen, view.Gen);
+        MG_Pipe::MGPipeSlots().Free(MG_Pipe::MGPipeKind::SamplerViewCso, reused);
+    }
+
+    // The five kinds that DO have a frontend object: their notice is raised by the object's own
+    // destructor today and by the client's helper after P4a's client packages land, so it is
+    // delivered twice for one death. A second delivery must be a no-op rather than a second
+    // free - which is what would drop a successor's twin under it.
+    struct KindCase {
+        const char* name;
+        MG_Pipe::MGPipeKind kind;
+        Uint64 lifetimeId;
+        // m-9: the handle the object held before it died, so the ABA leg below can prove the
+        // slot came back AT A MOVED GENERATION. ID-8's third case ("a notice for a slot
+        // re-minted at a new generation") was covered for SamplerViewCso only; a double free
+        // skips a generation, and nothing here would have caught that for the other five.
+        MG_Pipe::MGPipeHandle handle;
+    };
+    Vector<KindCase> cases;
+    {
+        auto texture = MakeShared<TextureObject2D>(0u);
+        auto renderbuffer = MakeShared<RenderbufferObject>(0u);
+        auto framebuffer = MakeShared<FramebufferObject>(1u);
+        auto sampler = MakeShared<SamplerObject>(0u);
+        auto program = MakeShared<ProgramObject>(0u);
+
+        TextureImpl::g_backendTextureObjects.GetOrCreate(SharedPtr<ITextureObject>(texture));
+        RenderbufferImpl::g_backendRenderbufferObjects.GetOrCreate(renderbuffer);
+        FramebufferImpl::g_backendFramebufferObjects.GetOrCreate(framebuffer);
+        SamplerImpl::g_backendSamplerObjects.GetOrCreate(sampler);
+        PrgramImpl::g_backendProgramObjects.GetOrCreate(program);
+
+        const auto handleFor = [](MG_Pipe::MGPipeKind kind, Uint64 lifetimeId) {
+            return MG_Pipe::MGPipeSlots().FindByLifetimeId(kind, lifetimeId);
+        };
+        cases.push_back({"Texture", MG_Pipe::MGPipeKind::Texture, texture->GetLifetimeId(),
+                         handleFor(MG_Pipe::MGPipeKind::Texture, texture->GetLifetimeId())});
+        cases.push_back({"Renderbuffer", MG_Pipe::MGPipeKind::Renderbuffer, renderbuffer->GetLifetimeId(),
+                         handleFor(MG_Pipe::MGPipeKind::Renderbuffer, renderbuffer->GetLifetimeId())});
+        cases.push_back({"Framebuffer", MG_Pipe::MGPipeKind::Framebuffer, framebuffer->GetLifetimeId(),
+                         handleFor(MG_Pipe::MGPipeKind::Framebuffer, framebuffer->GetLifetimeId())});
+        cases.push_back({"SamplerCso", MG_Pipe::MGPipeKind::SamplerCso, sampler->GetLifetimeId(),
+                         handleFor(MG_Pipe::MGPipeKind::SamplerCso, sampler->GetLifetimeId())});
+        cases.push_back({"ShaderCso", MG_Pipe::MGPipeKind::ShaderCso, program->GetLifetimeId(),
+                         handleFor(MG_Pipe::MGPipeKind::ShaderCso, program->GetLifetimeId())});
+
+        for (const auto& one : cases) {
+            EXPECT_FALSE(MG_Pipe::MGPipeHandleIsNull(
+                MG_Pipe::MGPipeSlots().FindByLifetimeId(one.kind, one.lifetimeId)))
+                << one.name << ": nothing was twinned, so this walk proves nothing";
+        }
+        // The real destructors run here and raise the first notice.
+    }
+
+    for (const auto& one : cases) {
+        EXPECT_TRUE(MG_Pipe::MGPipeHandleIsNull(
+            MG_Pipe::MGPipeSlots().FindByLifetimeId(one.kind, one.lifetimeId)))
+            << one.name << ": the object's own death did not return its slot";
+        // Second and third deliveries: nothing to resolve, nothing to free, no abort.
+        ops->OnDestroyed(one.kind, one.lifetimeId);
+        ops->OnDestroyed(one.kind, one.lifetimeId);
+        EXPECT_TRUE(MG_Pipe::MGPipeHandleIsNull(
+            MG_Pipe::MGPipeSlots().FindByLifetimeId(one.kind, one.lifetimeId)))
+            << one.name << ": a redundant notice resurrected a mapping";
+
+        // m-9, THE ABA LEG: the slot really came back, and its generation MOVED. Two redundant
+        // notices plus the object's own death are three chances to free one slot twice, and a
+        // double free is invisible in every assertion above - it shows up here, as a successor
+        // handed the same {slot, gen} the dead object held, which is precisely the handle a
+        // surviving memo would still be naming.
+        auto successor = MakeShared<TextureObject2D>(0u);
+        const MG_Pipe::MGPipeHandle reused =
+            MG_Pipe::MGPipeSlots().Acquire(one.kind, successor->GetLifetimeId());
+        ASSERT_FALSE(MG_Pipe::MGPipeHandleIsNull(reused)) << one.name;
+        if (reused.Slot == one.handle.Slot) {
+            EXPECT_NE(reused.Gen, one.handle.Gen)
+                << one.name << ": the slot came back at the SAME generation, so a memo holding "
+                              "the dead object's handle would resolve to its successor's twin";
+        }
+        MG_Pipe::MGPipeSlots().Free(one.kind, reused);
+    }
 }
 
 // The two-holder fix, end to end through the REAL Texture registry and the REAL destructor:
@@ -4372,6 +4775,10 @@ TEST(DirectGLESSlotTable, AGenerationBehindTheLiveTwinIsRefusedRatherThanAdopted
     GTEST_SKIP() << "the {slot, gen} twin table is compiled only under MOBILEGL_PIPE_PUSH";
 }
 
+TEST(DirectGLESSlotTable, ADeathNoticeForEveryP4aKindIsIdempotent) {
+    GTEST_SKIP() << "the {slot, gen} twin table is compiled only under MOBILEGL_PIPE_PUSH";
+}
+
 TEST(DirectGLESBufferDrawProbe, ALiveHostMapKeepsTheHandleArmProbeDirtyBetweenTwoDraws) {
     GTEST_SKIP() << "the handle-keyed resource table is compiled only under MOBILEGL_PIPE_PUSH";
 }

MobileGL/MG_Test/State/ObjectLifetimeIdTest.cpp

@@ -32,7 +32,11 @@
 #include "Includes.h"
 
 #include <MG_State/GLState/BufferState/BufferObject.h>
+#include <MG_State/GLState/FramebufferState/FramebufferObject.h>
+#include <MG_State/GLState/ProgramState/ProgramObject.h>
 #include <MG_State/GLState/RenderbufferState/RenderbufferObject.h>
+#include <MG_State/GLState/SamplerState/SamplerObject.h>
+#include <MG_State/GLState/TextureState/TextureObject2D.h>
 #include <MG_State/GLState/VertexArrayState/VertexArrayObject.h>
 
 using namespace MobileGL;
@@ -156,3 +160,69 @@ TEST(ObjectLifetimeIdTest, RenderbufferObjectAtARecycledAddressCarriesAFreshLife
 TEST(ObjectLifetimeIdTest, LiveRenderbufferObjectsHaveDistinctLifetimeIds) {
     ExpectDistinctIdsWhileBothAlive<MG_State::GLState::RenderbufferObject>("RenderbufferObject");
 }
+
+// P4a mints a client handle off the lifetime id of FOUR more object classes - a texture, a
+// framebuffer, a sampler and a program - and resolves every one of their death paths through
+// the same lifetimeId -> slot map. So the property these cases prove stops being a statement
+// about two backend memos and becomes the thing the whole handle space rests on: a recycled
+// heap address must not reproduce a handle, because the applier's record and the backend's twin
+// are both keyed on one.
+//
+// The texture case is additionally a CHURN check that costs nothing extra: under a push build
+// each round mints a Texture slot in the constructor and returns it in the destructor, so 64
+// rounds that leaked would be visible to the leak cases the gates package owns.
+TEST(ObjectLifetimeIdTest, TextureObjectAtARecycledAddressCarriesAFreshLifetimeId) {
+    using MG_State::GLState::TextureObject2D;
+    const int reuseCount = ProbeLifetimeIdAcrossAddressReuse<TextureObject2D>("TextureObject2D");
+    if (reuseCount == 0) {
+        GTEST_SKIP() << "inconclusive, not proven: this allocator never handed the same address back across 64 "
+                        "construct/destroy rounds, so the recycled-address case was never exercised";
+    }
+    RecordProperty("address_reuses_observed", reuseCount);
+}
+
+TEST(ObjectLifetimeIdTest, LiveTextureObjectsHaveDistinctLifetimeIds) {
+    ExpectDistinctIdsWhileBothAlive<MG_State::GLState::TextureObject2D>("TextureObject2D");
+}
+
+TEST(ObjectLifetimeIdTest, FramebufferObjectAtARecycledAddressCarriesAFreshLifetimeId) {
+    using MG_State::GLState::FramebufferObject;
+    const int reuseCount = ProbeLifetimeIdAcrossAddressReuse<FramebufferObject>("FramebufferObject");
+    if (reuseCount == 0) {
+        GTEST_SKIP() << "inconclusive, not proven: this allocator never handed the same address back across 64 "
+                        "construct/destroy rounds, so the recycled-address case was never exercised";
+    }
+    RecordProperty("address_reuses_observed", reuseCount);
+}
+
+TEST(ObjectLifetimeIdTest, LiveFramebufferObjectsHaveDistinctLifetimeIds) {
+    ExpectDistinctIdsWhileBothAlive<MG_State::GLState::FramebufferObject>("FramebufferObject");
+}
+
+TEST(ObjectLifetimeIdTest, SamplerObjectAtARecycledAddressCarriesAFreshLifetimeId) {
+    using MG_State::GLState::SamplerObject;
+    const int reuseCount = ProbeLifetimeIdAcrossAddressReuse<SamplerObject>("SamplerObject");
+    if (reuseCount == 0) {
+        GTEST_SKIP() << "inconclusive, not proven: this allocator never handed the same address back across 64 "
+                        "construct/destroy rounds, so the recycled-address case was never exercised";
+    }
+    RecordProperty("address_reuses_observed", reuseCount);
+}
+
+TEST(ObjectLifetimeIdTest, LiveSamplerObjectsHaveDistinctLifetimeIds) {
+    ExpectDistinctIdsWhileBothAlive<MG_State::GLState::SamplerObject>("SamplerObject");
+}
+
+TEST(ObjectLifetimeIdTest, ProgramObjectAtARecycledAddressCarriesAFreshLifetimeId) {
+    using MG_State::GLState::ProgramObject;
+    const int reuseCount = ProbeLifetimeIdAcrossAddressReuse<ProgramObject>("ProgramObject");
+    if (reuseCount == 0) {
+        GTEST_SKIP() << "inconclusive, not proven: this allocator never handed the same address back across 64 "
+                        "construct/destroy rounds, so the recycled-address case was never exercised";
+    }
+    RecordProperty("address_reuses_observed", reuseCount);
+}
+
+TEST(ObjectLifetimeIdTest, LiveProgramObjectsHaveDistinctLifetimeIds) {
+    ExpectDistinctIdsWhileBothAlive<MG_State::GLState::ProgramObject>("ProgramObject");
+}

android-plugin/trace-replay-ci.sh

@@ -367,7 +367,9 @@ run_retrace() {
   mkdir -p "${result_dir}"
   # A repeat run of a case the previous invocation already installed and pushed only needs
   # the on-device copy back into a fresh app output directory.
-  if [ "${reuse_fixture}" -eq 0 ]; then
+  # MOBILEGL_TRACE_SKIP_INSTALL=1: the caller installed the APK itself (ColorOS shows an install-confirmation
+  # dialog whose tap drops adb for a few seconds, so the install has to be done and settled outside a run).
+  if [ "${reuse_fixture}" -eq 0 ] && [ "${MOBILEGL_TRACE_SKIP_INSTALL:-0}" != "1" ]; then
     "${ADB}" install -r "$(host_path_for_adb "${apk_file}")"
   fi
   copy_fixture_to_app

scripts/gen_pipe_dirty_surface.py

@@ -1811,17 +1811,21 @@ def self_test(scanned, bits, publishers, movers, moved, outside=None, undecided_
                 "20%s (the %s row is STALE the moment the scan stops finding it)"
                 % ("abcd"[index], name))
 
-    # 21. THE TWO UNDECIDED MARKS ARE STILL LOAD-BEARING. Dropping them has to make --check
-    #     refuse both rows as unmarked UNDECIDED - which is what says the marks are covering a
-    #     real blind spot rather than a verdict the analysis could give today. Control 18 is
-    #     the other direction: a mark the derivation DOES decide is itself a problem, so
-    #     neither of these can outlive its reason.
+    # 21. EVERY UNDECIDED MARK IS STILL LOAD-BEARING. Dropping them all has to make --check
+    #     refuse EVERY marked (mutator, bit) as an unmarked UNDECIDED, and nothing else - which
+    #     is what says each mark is covering a real blind spot rather than a verdict the
+    #     analysis could give today. Control 18 is the other direction: a mark the derivation
+    #     DOES decide is itself a problem, so no mark can outlive its reason. Read from the
+    #     file's own list rather than spelled here, so a row that gains a bit - UseProgram
+    #     gained NEW_SAMPLER_VIEWS and NEW_SHADER_IMAGES at the P4a fable seam round - cannot
+    #     silently turn this control into one that counts the wrong number.
     problems, _, _, undecided_rows = object_class_problems(real, bits, movers, moved, outside, {})
-    tripped(any(p.startswith("UNDECIDED answer NEW_SHADER for UseProgram") for p in problems)
-            and any(p.startswith("UNDECIDED answer NEW_VERTEX_ELEMENTS for BindVertexArray")
-                    for p in problems)
-            and len(undecided_rows) == 2,
-            "21 (the two P4a undecided marks are still needed)")
+    marked_pairs = sorted((mutator, bit) for mutator, marks in real_marks.items() for bit in marks)
+    tripped(marked_pairs
+            and all(any(p.startswith("UNDECIDED answer %s for %s" % (bit, mutator)) for p in problems)
+                    for mutator, bit in marked_pairs)
+            and len(undecided_rows) == len(marked_pairs),
+            "21 (every P4a undecided mark - %d of them - is still needed)" % len(marked_pairs))
 
     # THE POSITIVE CONTROLS. (a) The row that was wrong in round 3: SetPixelStoreParam writes
     # NEW_PIXEL_PACK's shutter member sixteen times, through a token-pasting macro; it has

scripts/p4a_descriptor_negative_control.sh

@@ -0,0 +1,520 @@
+#!/usr/bin/env bash
+# G7's negative controls for P4a: drop one field from each of two descriptor conversions on purpose
+# and prove the emission-consistency suites say so, NAMING the field.
+#
+# WHAT G6 CLAIMS. For every framebuffer configuration, texture object, sampler object and program
+# the client's emitted MGPFramebufferState / MGPResourceDesc / MGPTextureParams / MGPSamplerDesc /
+# MGPSamplerView / MGPProgramDesc reproduce EXACTLY the values Espryt's SyncToBackend family reads
+# from the frontend today, field by field. MG_Test/Pipe/{FramebufferEmit,TextureEmit,SamplerEmit,
+# ImageEmit,ProgramEmit}Test.cpp are what walk it.
+#
+# WHY A CONTROL IS NEEDED AT ALL. Those suites are green on a correct conversion, and they would be
+# just as green on a conversion they had stopped looking at: a walk that drove no configurations, a
+# comparison that stopped reading the record, an assertion someone loosened. Green says nothing
+# about whether a suite can still fail. This script makes each of them fail, for the one reason it
+# exists to catch, and reports a NON-ZERO ctest THAT NAMES THE DROPPED FIELD as the pass.
+#
+# THE TWO BREAKS, one per new conversion family, each a break the COMPILER CANNOT SEE - the struct
+# still has the member, the record is still its pinned size, the PipeFields.def row still names it
+# and the generated comparator still compares it. What breaks is the VALUE:
+#
+#   1. MGPSurface::Layered stops being copied in MG_Impl/Pipe/FramebufferEmit.h. A layered
+#      attachment travels as a non-layered one, which is the shape that turns a whole-array render
+#      target into slice 0 - and SupportsLayeredImageBinding's rule (DirectGLES.cpp:1992-2013,
+#      D-O) forces `layer` to 0 for a non-layerable target, so the wrong answer is silently
+#      plausible rather than an error. It is also the field with the least other coverage: the
+#      surface's Res, Level and Layer are all still right, so nothing about the ATTACHMENT changes
+#      except the one bit that says how much of the texture it is.
+#      TWO MECHANISMS, NOT ONE, on a tree that carries the framebuffer emitter (review F-m8): the
+#      regex also matches the field's copy inside the ContentHash staging helper, so the run drops
+#      Layered from the emitted record AND from the framebuffer content hash. The suite still goes
+#      red naming the field, which is what the control asks; the sentence above is narrowed here
+#      rather than in the code because excluding the hash copy would mean hard-coding another
+#      package's helper name into a regex that deliberately does not know one.
+#   2. SamplerParameters::borderColorForm stops being copied in MG_Impl/Pipe/SamplerEmit.h. All
+#      four border-colour VALUES still cross; what is lost is which of the three forms
+#      (float / int / uint) they are to be read as, and D-F4 is explicit that the form crosses and
+#      that all four values are compared. The failure it models is IntegerBorderColorScenario's:
+#      an integer border colour read as floats is not an error anywhere, it is just the wrong
+#      colour at the clamped edge of every sampled texture.
+#
+# Each patch is applied by REGEX rather than by an exact line, because both headers belong to OTHER
+# PACKAGES (C.7: FramebufferEmit.h is package B's, SamplerEmit.h is package C's) and their spelling
+# is theirs to choose: any `<something>.<field> = <expr>;` - or the designated-initializer
+# `.<field> = <expr>,` - has its right-hand side replaced by a constant. If a header does not
+# assign its field at all, because the emitter has not landed yet or because the conversion is
+# spelled some other way, that is exit 2, "could not run", never a pass.
+#
+# THE CONSTANT IS `{}` AND NOT `0`, and the one character is the difference between a control that
+# can answer and one that cannot (review F-M1). SamplerParameters::borderColorForm is a SCOPED enum
+# (MG_Pipe/MGPipeValueTypes.h, `enum class BorderColorForm : Uint8`), and `x = 0` on one is
+# `cannot convert 'int' to 'BorderColorForm' in assignment` - the patched header does not compile,
+# the script takes its "the patched header did not compile" path, and the control reports
+# could-not-run FOREVER, on every tree, with a summary line saying that exit 2 is the expected
+# answer here. `x = {}` is valid for the scoped enum AND for MGPSurface::Layered (a Uint8), so ONE
+# replacement covers both controls and neither of them needs to know its field's type.
+#
+# A CONTROL'S FIELD MUST MATTER IN AT LEAST ONE CASE. `{}` is the type's zero, so a suite whose
+# every case happens to expect the zero value of the field would stay green with the copy dropped -
+# which this script would then report, correctly, as "the negative control did not trip". Both
+# suites' headers say they must fail BY FIELD NAME, and both drive a non-default value; that is the
+# owning package's contract, and this script is what checks it rather than assuming it.
+#
+# ON THE P4a CONTRACT TREE THIS SCRIPT EXITS 2 AND SAYS SO. Both headers EXIST there - the contract
+# commit creates all five emit headers with STUB emitters that return 0 payload bytes (contract-v1
+# D1) - but neither assigns anything, so there is no field copy to drop. That is the honest report:
+# a control that "passed" because there was nothing to break would be the worst outcome available.
+#
+# WHY IT IS NOT A CI LANE. It rebuilds the library up to four times. It is run by hand, and by the
+# integrator at the P4a five-part gate (D.3 part 3, beside P2's g7_negative_control.sh and P3a's
+# p3a_vertex_input_negative_control.sh, both of which keep running unchanged).
+#
+# Usage:
+#   scripts/p4a_descriptor_negative_control.sh <build-dir>
+#
+#   <build-dir>   a configured build directory carrying the push-only unit suites (the emission
+#                 cases are compiled only under MOBILEGL_PIPE_PUSH). It is CHECKED, not assumed:
+#                 in a pull build every emission case is a visible skip, ctest is green before and
+#                 after the patch, and the run would record "the negative control did not trip" -
+#                 a finding about the suite that is really a finding about the build directory
+#                 (review F-m10). MOBILEGL_PIPE_PUSH is read out of the directory's CMakeCache.txt.
+#
+# RESTORE IS NOT ENOUGH; THE REBUILD IS PART OF THE CONTRACT. Once a header has been patched, EVERY
+# way out of this script goes through repair(): restore the header, rebuild the library from it, and
+# re-run the suite to prove the tree really went back. `cp` alone leaves <build-dir> holding a
+# libMobileGL.so in which the field is hard-wired, `ctest` does not rebuild, and nothing in an exit
+# status tells a caller to. The path that needs this most is the one that reads "NEGATIVE CONTROL
+# DID NOT TRIP": an engineer reacts to it by opening the suite and re-running ctest against this
+# very build directory, and every reading they take there would come from a deliberately corrupted
+# library. So repair() runs from the EXIT trap as well - a mid-way failure (a patched header that
+# would not compile, an interrupt) repairs too - and a repair that itself fails downgrades the
+# verdict to 2. That downgrade is delivered from THREE places, and REPAIR_RC is what makes the
+# last two of them possible (review F-v2-m4, which found it set and never read): run_control's
+# own `if ! repair` turns a failed repair into 'could-not-run' for that control; the check after
+# the control loop catches a repair that failed on any earlier path and forces the run's exit
+# code to 2; and the EXIT trap reads it too, so a repair that fails while the script is on its
+# way out through an early `exit` cannot leave a corrupted build directory behind a 0 or a 1. The state repair() reads lives in THIS shell and not in a command substitution,
+# which is what makes the trap version of it a real repair rather than a no-op, and every child's
+# exit status is additionally checked for "killed by a signal" so that a Ctrl-C stops the run
+# instead of carrying on into the next control and signing off with a verdict about a control
+# nobody ran. On the exits that happen BEFORE any patch (bad arguments, a missing header, a
+# missing suite) the tree was never touched and the build directory still holds what the caller
+# built: there is nothing to restore and nothing to rebuild, and the script says which of the two
+# situations it is leaving behind.
+#
+# Nothing is written into the repository. Logs and the header backups live in
+# <build-dir>/p4a-g7-logs/, which is inside the build tree and therefore neither committed nor
+# picked up by `git status`; the paths are printed with every verdict.
+#
+# Exit codes: 0 BOTH controls tripped AND named their field;
+#             1 a control did not answer: a suite stayed green with its field dropped, or it went
+#               red without ever naming the field, so the red cannot be attributed to the drop.
+#               Both are findings about the TEST, not errors in this script - and both leave the
+#               tree restored AND rebuilt AND re-run;
+#             2 a control could not be run at all (bad arguments; a build directory that is not a
+#               push one; a header or a field absent on this tree; no matching test; a build that
+#               was already broken; a patched header that did not compile; a failed restore or a
+#               failed rebuild after one; the run was INTERRUPTED). Exit 2 wins over exit 1:
+#               "could not run" is never reported as "did not answer".
+set -u -o pipefail
+
+BUILD_DIR=""
+while [ $# -gt 0 ]; do
+  case "$1" in
+    -*) echo "unknown arg: $1" >&2; exit 2 ;;
+    *) BUILD_DIR=$1; shift ;;
+  esac
+done
+[ -n "$BUILD_DIR" ] || { echo "usage: $0 <build-dir>" >&2; exit 2; }
+
+REPO_ROOT=$(cd "$(dirname "$0")/.." && pwd) || exit 2
+cd "$REPO_ROOT" || exit 2
+[ -f "$BUILD_DIR/CMakeCache.txt" ] || { echo "$BUILD_DIR is not a configured build directory" >&2; exit 2; }
+
+# F-m10: a PULL build directory would take both controls through "did-not-trip", which reads as a
+# finding about the suites and is a finding about the argument. Every emission case is
+# `#if MOBILEGL_PIPE_PUSH` and a visible skip otherwise, so ctest is green before the patch and
+# green after it, and the script would report a defect in somebody else's test suite.
+#
+# BOTH CACHE ENTRIES ARE READ, because MOBILEGL_PIPE_VERIFY=ON forces MOBILEGL_PIPE_PUSH on for
+# the configure WITHOUT writing it back to the cache (CMakeLists.txt: the `set(... ON)` shadows the
+# cached OFF). A verify build directory therefore compiles the emission cases while its cache still
+# says MOBILEGL_PIPE_PUSH:BOOL=OFF, and refusing it would be exactly the wrong answer.
+mgl_cache_is_on() {
+  local line
+  line=$(grep -m1 "^$1:" "$BUILD_DIR/CMakeCache.txt" 2>/dev/null) || return 1
+  case "${line#*=}" in
+    ON|On|on|1|TRUE|True|true|YES|Yes|yes|Y|y) return 0 ;;
+    *) return 1 ;;
+  esac
+}
+if ! mgl_cache_is_on MOBILEGL_PIPE_PUSH && ! mgl_cache_is_on MOBILEGL_PIPE_VERIFY; then
+  echo "$BUILD_DIR does not carry the push-only emission cases:" >&2
+  grep -E '^MOBILEGL_PIPE_(PUSH|VERIFY):' "$BUILD_DIR/CMakeCache.txt" >&2 || \
+    echo "  (its CMakeCache.txt names neither MOBILEGL_PIPE_PUSH nor MOBILEGL_PIPE_VERIFY)" >&2
+  echo "Every case in MG_Test/Pipe/{Framebuffer,Sampler}EmitTest.cpp is #if MOBILEGL_PIPE_PUSH and" >&2
+  echo "a visible skip otherwise, so here ctest is green with the field dropped as well as without" >&2
+  echo "it and this script would report 'the negative control did not trip' about a suite that" >&2
+  echo "never ran - a finding about the build directory dressed up as a finding about the test." >&2
+  echo "Point it at the push (or verify) build directory." >&2
+  exit 2
+fi
+
+# One row per control: <header>@<field>@<ctest regex>@<owning package>. The ctest regex is the
+# SHORTEST string that selects only that suite, the way the CI filters are written.
+CONTROLS="\
+MobileGL/MG_Impl/Pipe/FramebufferEmit.h@Layered@FramebufferEmit\.@B (clientfb)
+MobileGL/MG_Impl/Pipe/SamplerEmit.h@borderColorForm@SamplerEmit\.@C (clientsp)"
+
+# Inside the build tree, never in the repository: a run must not leave untracked files behind, and
+# .gitignore carries no rule for a p4a-*.log at the root. Falls back to a temp directory only if
+# the build directory cannot be written, which would be a strange build directory.
+LOG_DIR=$(cd "$BUILD_DIR" && pwd)/p4a-g7-logs
+mkdir -p "$LOG_DIR" 2>/dev/null || LOG_DIR=$(mktemp -d) || exit 2
+
+say() { echo "[p4a-g7] $*" >&2; }
+
+# --- the repair, shared by every exit path ---------------------------------------------------
+# PATCHED_HEADER is the one header currently patched, empty when the tree is pristine. Only one
+# control is ever in flight at a time, deliberately: two simultaneous drops would make a red
+# unattributable to either.
+PATCHED_HEADER=""
+PATCHED_BACKUP=""
+PATCHED_TEST=""
+# Sticky across every repair this run performs: 0 while every repair put the tree back, 2 once
+# any of them did not. Read in three places (see the header): run_control's `if ! repair`, the
+# check after the control loop, and the EXIT trap. It is sticky rather than per-call because a
+# build directory that was once left un-restored stays untrustworthy even if a later repair of a
+# different header succeeds.
+REPAIR_RC=0
+repair() {
+  [ -n "$PATCHED_HEADER" ] || return 0
+  local header=$PATCHED_HEADER backup=$PATCHED_BACKUP test=$PATCHED_TEST
+  # Cleared FIRST, so a repair that is re-entered (the explicit call, then the EXIT trap) does the
+  # work once and reports the same answer twice.
+  PATCHED_HEADER=""
+  # From the byte-for-byte copy taken before the patch, never from git: someone running this on a
+  # dirty tree must get their own tree back, not HEAD.
+  if [ -f "$backup" ]; then cp -f "$backup" "$header" || { REPAIR_RC=2; return 2; }; fi
+  say "restored $header; rebuilding $BUILD_DIR from it"
+  if ! cmake --build "$BUILD_DIR" -j "$(nproc)" </dev/null > "$LOG_DIR/build-restored.log" 2>&1; then
+    say "the tree did NOT rebuild after the restore - see $LOG_DIR/build-restored.log"
+    say "THE BUILD DIRECTORY IS NOT TRUSTWORTHY: repair it before reading anything out of it."
+    REPAIR_RC=2
+    return 2
+  fi
+  if ! ctest --test-dir "$BUILD_DIR" -R "$test" --no-tests=error </dev/null \
+       > "$LOG_DIR/ctest-restored.log" 2>&1; then
+    say "the tree did NOT go back to green after the restore - see $LOG_DIR/ctest-restored.log"
+    REPAIR_RC=2
+    return 2
+  fi
+  say "the tree is restored, rebuilt and green again"
+  return 0
+}
+
+# INT and TERM as well as EXIT (p3a-g7 m3). A Ctrl-C during a rebuild would otherwise leave the
+# patched header in the tree - bash runs no EXIT trap for an uncaught SIGINT - and the next thing
+# that reader does is build, from a hard-wired field, with nothing saying so. The two extra traps
+# repair and then re-raise with the default disposition, so the exit status still reports the
+# signal. Armed for the whole run: before the first patch repair() is a no-op.
+#
+# AND THE TRAPS ARE NOT THE ONLY DETECTION, because bash's SIGINT semantics do not guarantee that
+# they run. A Ctrl-C in a terminal goes to the whole PROCESS GROUP, so the `cmake` this script is
+# waiting on dies first and returns 130 - and bash, having a handler installed, may go on to the
+# next command rather than to the trap. Measured exactly that way: the tree WAS repaired (through
+# the explicit failure path below, which is why the state has to live in this shell), but the run
+# then carried on into the second control and signed off with the summary it prints on an
+# untouched contract tree. Repaired and wrong is still wrong. So every child's status is checked
+# for "killed by a signal" as well, INTERRUPTED latches either way, and the run stops and says so.
+INTERRUPTED=""
+note_interrupt() { [ -n "$INTERRUPTED" ] || INTERRUPTED=$1; }
+# 128 + signal number is how a shell reports a child that died on a signal; nothing this script
+# runs exits above 128 for any other reason (ctest uses 8 for failing tests).
+child_was_signalled() { [ "${1:-0}" -ge 128 ]; }
+trap 'note_interrupt INT; repair; trap - INT; kill -INT $$' INT
+trap 'note_interrupt TERM; repair; trap - TERM; kill -TERM $$' TERM
+# The EXIT trap covers the paths that leave through an early `exit` with a header still patched
+# (a patch that would not compile, a build that failed). On those the status is already chosen,
+# so the trap has to OVERRIDE it when the repair did not put the tree back - which is what makes
+# REPAIR_RC readable at all from here. Calling `exit` inside an EXIT trap replaces the status and
+# does not re-enter the trap.
+on_exit() {
+  repair || true
+  if [ "$REPAIR_RC" -ne 0 ]; then
+    say "a repair did NOT put the tree back; exit 2 regardless of what this run was going to say."
+    say "THE BUILD DIRECTORY IS NOT TRUSTWORTHY: repair it before reading anything out of it."
+    exit 2
+  fi
+}
+trap 'on_exit' EXIT
+
+# --- one control -----------------------------------------------------------------------------
+# Sets the GLOBAL CONTROL_VERDICT to "tripped" / "did-not-trip" / "wrong-reason" /
+# "could-not-run"; everything it has to say goes to stderr. The tree is repaired before it
+# returns, whatever the answer.
+#
+# A GLOBAL AND NOT AN ECHO, AND IT IS CALLED PLAINLY AND NOT IN `$(...)` (review F-M2 and F-M3,
+# two separate defects that the same change closes). The earlier form was
+# `verdict=$(run_control ...)`, and a command substitution is a SUBSHELL:
+#
+#   * F-M2 - anything the function or anything it called wrote to stdout became part of
+#     `$verdict`. The patcher's own success line did, so on a tree where a control really tripped
+#     the verdict was a TWO-LINE string, the `case` fell through to `*)`, and the run scored a
+#     control that had answered perfectly as "a control did not answer". Exit 0 was unreachable.
+#     The patcher now writes to stderr as well (belt and braces), but the verdict no longer
+#     travels through a stream that anything else can write to, which is the actual fix.
+#   * F-M3 - PATCHED_HEADER was assigned INSIDE that subshell. Bash resets a script's traps in a
+#     command substitution, so the subshell had no traps to fire, and its assignments never
+#     reached the parent, so the parent's EXIT/INT/TERM traps ran with PATCHED_HEADER empty and
+#     repair() returned 0 immediately. A Ctrl-C during a rebuild left the patched header in the
+#     tree - the exact thing the header's own paragraph promises cannot happen, and the p3a-g7 m3
+#     lesson it cites. Called plainly, the state is the parent's and the traps repair.
+CONTROL_VERDICT=""
+run_control() {
+  local header=$1 field=$2 test=$3 owner=$4
+  local tag matched
+  tag=$(basename "$header" .h)-$field
+  CONTROL_VERDICT=could-not-run
+
+  # 0. the control has to have something to break.
+  if [ ! -f "$header" ]; then
+    say "$header does not exist on this tree."
+    say "It is P4a package $owner's file (BRIEF-P4A.md C.5/C.7): the client-side emitter that"
+    say "carries the ${field} copy. Until it lands there is no field copy to drop, so this control"
+    say "cannot run and MUST NOT report a pass. Re-run on a tree that carries that package."
+    CONTROL_VERDICT=could-not-run
+    return
+  fi
+  if ! grep -qE "\.${field}[[:space:]]*=" "$header"; then
+    say "$header exists but assigns no .${field}."
+    say "On the P4a CONTRACT tree that is the expected answer: the contract commit creates all five"
+    say "emit headers with STUB emitters (contract-v1 D1) that return 0 payload bytes and copy"
+    say "nothing, and package $owner fills the body in. Later in the phase it means something else"
+    say "and worse - either the conversion moved out of this header, or it does not copy ${field}"
+    say "at all, and the second one would mean G6 is already broken in exactly the way this control"
+    say "is supposed to create. Neither is something this script may report as a pass; look at the"
+    say "header."
+    CONTROL_VERDICT=could-not-run
+    return
+  fi
+
+  # 1. the suite has to exist, and be green, BEFORE the break. A missing test is NOT a pass:
+  #    without this the script would patch, watch ctest match nothing, read that as "the test
+  #    failed" and report the control as tripped.
+  matched=$(ctest --test-dir "$BUILD_DIR" -N -R "$test" 2>/dev/null | grep -cE '^ *Test *#[0-9]+:')
+  if [ "${matched:-0}" -eq 0 ]; then
+    say "no test matches $test in $BUILD_DIR."
+    say "The suite is registered by the P4a contract commit; until it carries the emission cases"
+    say "this control has nothing to trip and cannot report a pass."
+    CONTROL_VERDICT=could-not-run
+    return
+  fi
+  say "[$tag] $matched matching test(s) before the patch"
+
+  say "[$tag] building $BUILD_DIR as it is"
+  if ! cmake --build "$BUILD_DIR" -j "$(nproc)" </dev/null > "$LOG_DIR/build-before-$tag.log" 2>&1; then
+    say "[$tag] the build is already broken before any patch - see $LOG_DIR/build-before-$tag.log"
+    tail -20 "$LOG_DIR/build-before-$tag.log" >&2
+    CONTROL_VERDICT=could-not-run
+    return
+  fi
+  if ! ctest --test-dir "$BUILD_DIR" -R "$test" --no-tests=error --output-on-failure </dev/null \
+       > "$LOG_DIR/ctest-before-$tag.log" 2>&1; then
+    say "[$tag] $test is already red before the patch - fix that first, the control proves nothing"
+    tail -30 "$LOG_DIR/ctest-before-$tag.log" >&2
+    CONTROL_VERDICT=could-not-run
+    return
+  fi
+  say "[$tag] $test is green before the patch"
+
+  # 2. stop copying the field.
+  PATCHED_BACKUP=$LOG_DIR/$(basename "$header").orig
+  PATCHED_TEST=$test
+  cp -f "$header" "$PATCHED_BACKUP" || { CONTROL_VERDICT=could-not-run; return; }
+  # Set BEFORE the patcher runs, not after: a python that died half-way through the write must
+  # still be repaired. The cost is one unnecessary rebuild in the case where the patcher matched
+  # nothing and the file is byte-identical (cp refreshes its mtime).
+  PATCHED_HEADER=$header
+  say "[$tag] dropping the ${field} copy from $header"
+  if ! python3 - "$header" "$field" <<'PY'
+import re
+import sys
+
+path, field = sys.argv[1], sys.argv[2]
+text = open(path, encoding='utf-8').read()
+# `<lhs>.Layered = <expr>;` and the designated-initializer `.Layered = <expr>,`. The right-hand
+# side is REPLACED rather than the line deleted, so the record still HAS the field and the break
+# stays one the compiler cannot see.
+pattern = re.compile(r'(\.' + re.escape(field) + r'\s*=\s*)([^;,\n]+)([;,])')
+# `{}` and not `0`: borderColorForm is a SCOPED enum (enum class BorderColorForm : Uint8) and
+# `= 0` does not convert, so the patched header would never compile and this control could
+# never answer (review F-M1). `= {}` is valid for the scoped enum and for MGPSurface::Layered's
+# Uint8 alike, in an assignment and in a designated initializer, so one string covers both.
+patched, count = pattern.subn(r'\g<1>{} /* G7 NEGATIVE CONTROL: was \g<2> */\g<3>', text)
+if count == 0:
+    sys.stderr.write('[p4a-g7] no assignment to .%s to patch - the header changed shape since this '
+                     'control was written; update the control, do not delete it.\n' % field)
+    sys.exit(1)
+open(path, 'w', encoding='utf-8', newline='\n').write(patched)
+# STDERR, like every other diagnostic here: this used to be the one line in the file that
+# went to stdout, and stdout was the channel the caller captured the verdict through.
+sys.stderr.write('[p4a-g7] neutralised %d assignment(s) to .%s\n' % (count, field))
+PY
+  then
+    say "[$tag] the patcher did not apply; the tree is repaired on the way out"
+    repair || true
+    CONTROL_VERDICT=could-not-run
+    return
+  fi
+
+  # 3. it must still COMPILE. A build break here would prove the static_asserts work, not that the
+  #    suite still checks.
+  say "[$tag] rebuilding with the dropped field"
+  cmake --build "$BUILD_DIR" -j "$(nproc)" </dev/null > "$LOG_DIR/build-after-$tag.log" 2>&1
+  buildRc=$?
+  if child_was_signalled "$buildRc" || [ -n "$INTERRUPTED" ]; then
+    note_interrupt "exit $buildRc"
+    say "[$tag] INTERRUPTED during the rebuild ($INTERRUPTED). Repairing the tree and stopping:"
+    say "a run that carried on here would report a verdict about a control that never ran."
+    repair || true
+    CONTROL_VERDICT=could-not-run
+    return
+  fi
+  if [ "$buildRc" -ne 0 ]; then
+    say "[$tag] the patched header did not compile, so the control cannot tell 'the test failed'"
+    say "from 'nothing was built'. The break is supposed to be invisible to the compiler - if the"
+    say "field is read somewhere that needs its value, say so in the control rather than working"
+    say "around it."
+    grep -m10 -E 'error:' "$LOG_DIR/build-after-$tag.log" >&2
+    repair || true
+    CONTROL_VERDICT=could-not-run
+    return
+  fi
+  say "[$tag] the patched header still compiles, so the record still has the field and its size"
+
+  # 4. the suite must now be RED, and NAME the field. The verdict is only RECORDED here; nothing is
+  #    reported and nothing returns until step 5 has put the tree back, because all three outcomes
+  #    leave the same corrupted build directory behind.
+  say "[$tag] running $test against the dropped field"
+  ctest --test-dir "$BUILD_DIR" -R "$test" --no-tests=error --output-on-failure </dev/null \
+       > "$LOG_DIR/ctest-after-$tag.log" 2>&1
+  ctestRc=$?
+  if child_was_signalled "$ctestRc" || [ -n "$INTERRUPTED" ]; then
+    note_interrupt "exit $ctestRc"
+    say "[$tag] INTERRUPTED while running $test ($INTERRUPTED). A suite that was killed is not a"
+    say "suite that went red: repairing the tree and stopping rather than scoring the control."
+    repair || true
+    CONTROL_VERDICT=could-not-run
+    return
+  fi
+  if [ "$ctestRc" -eq 0 ]; then
+    CONTROL_VERDICT=did-not-trip
+  elif awk '/: Failure$/ || /: error:/ { block = 1 } block { print } /^[[:space:]]*$/ { block = 0 }' \
+         "$LOG_DIR/ctest-after-$tag.log" | grep -q "$field"; then
+    # A red is not yet a pass: a suite that had started failing for an unrelated reason satisfies
+    # the first half of the claim and none of the second. Matched against the FAILING ASSERTIONS'
+    # OWN BLOCKS rather than the whole ctest log (p3a-g7 m3): gtest prints a failure as
+    # `<file>:<line>: Failure` followed by the compared expressions and their values, terminated by
+    # a blank line, and the field name appears among those expressions - so the block, not the
+    # line, is the right unit and the whole file is the wrong one. A case NAMED after the field, a
+    # skip reason quoting it or a compiler note echoed into the log would all have made "tripped"
+    # mean "the string exists somewhere in the output".
+    CONTROL_VERDICT=tripped
+  else
+    CONTROL_VERDICT=wrong-reason
+  fi
+
+  # 5. put it back, and prove it went back. SHARED BY ALL THREE OUTCOMES, and that is the whole
+  #    point of doing it before the verdict is reported.
+  if ! repair; then
+    say "[$tag] the control's own verdict was '$CONTROL_VERDICT', but the repair failed, so that"
+    say "verdict is not what this run reports: a build directory that could not be put back is"
+    say "'could not run'."
+    CONTROL_VERDICT=could-not-run
+    return
+  fi
+
+  case "$CONTROL_VERDICT" in
+    did-not-trip)
+      say "[$tag] NEGATIVE CONTROL DID NOT TRIP: $test was still green with ${field} no longer"
+      say "copied into the record. The emission comparison did not notice a field it claims to"
+      say "compare, so G6 is not checking what it claims to check."
+      say "The run's output is kept at $LOG_DIR/ctest-after-$tag.log"
+      ;;
+    wrong-reason)
+      say "[$tag] INCONCLUSIVE: $test went red with ${field} dropped but never named it, so the red"
+      say "cannot be attributed to the dropped field. The suite failed for some other reason."
+      grep -m20 -E 'Failure|error|Expected|Actual' "$LOG_DIR/ctest-after-$tag.log" >&2
+      say "The run's output is kept at $LOG_DIR/ctest-after-$tag.log"
+      ;;
+    tripped)
+      say "[$tag] negative control tripped, naming $field, and the tree is green again"
+      ;;
+  esac
+}
+
+# --- both controls, then one verdict ----------------------------------------------------------
+# Both are ALWAYS run, even when the first could not run: "FramebufferEmit has no emitter yet and
+# SamplerEmit does" is a different tree from "neither does", and an engineer reading this output
+# needs to know which. The exit code is the worst of the two, with 2 (could not run) outranking
+# 1 (did not answer).
+WORST=0
+SUMMARY=""
+# The rows are collected FIRST and the loop over them carries no redirection, so that
+# run_control - which is called plainly now, in this shell, holding this shell's repair state -
+# cannot have the remaining rows eaten out from under it by a child that reads stdin. (cmake and
+# ctest are also given /dev/null explicitly below; this is the belt to that pair of braces.)
+CONTROL_ROWS=()
+while IFS= read -r mglRow; do
+  [ -n "$mglRow" ] && CONTROL_ROWS+=("$mglRow")
+done <<EOF
+$CONTROLS
+EOF
+
+for mglRow in "${CONTROL_ROWS[@]}"; do
+  IFS='@' read -r header field test owner <<< "$mglRow"
+  [ -n "$header" ] || continue
+  run_control "$header" "$field" "$test" "$owner"
+  verdict=$CONTROL_VERDICT
+  SUMMARY="$SUMMARY
+  $field ($header): $verdict"
+  case "$verdict" in
+    tripped) ;;
+    could-not-run) WORST=2 ;;
+    *) [ "$WORST" -eq 2 ] || WORST=1 ;;
+  esac
+  if [ -n "$INTERRUPTED" ]; then
+    SUMMARY="$SUMMARY
+  (INTERRUPTED - the remaining control(s) did not run)"
+    WORST=2
+    break
+  fi
+done
+
+# Every repair this run performed, read once. run_control already turns a failed repair of the
+# control it is running into 'could-not-run', so this only ever fires for a repair that failed
+# somewhere run_control does not report from - but the whole point of a sticky flag is that the
+# verdict may not be better than the state of the build directory it was measured in.
+if [ "$REPAIR_RC" -ne 0 ]; then
+  SUMMARY="$SUMMARY
+  (a repair did NOT put the tree back - the build directory is not trustworthy)"
+  WORST=2
+fi
+
+trap - EXIT
+say "---- G7 (P4a descriptor emission) ----$SUMMARY"
+case "$WORST" in
+  0) say "both controls tripped and named their field; exit 0" ;;
+  1) say "a control did not answer; exit 1" ;;
+  2) if [ -n "$INTERRUPTED" ]; then
+       say "the run was INTERRUPTED ($INTERRUPTED); exit 2. The tree was repaired before this line -"
+       say "\`git status\` is the check - and NOTHING here is a verdict about the controls."
+     else
+       say "a control could not be run; exit 2 (this is the expected answer on the P4a contract tree,"
+       say "where both emit headers are the contract's stubs and copy nothing)"
+     fi ;;
+esac
+# A run this shell interrupted still exits 2 rather than by signal, because the INT trap's
+# re-raise only happens when bash actually reaches the trap. The summary above says which it was.
+exit "$WORST"

scripts/p4a_untouched_regions.sh

@@ -0,0 +1,709 @@
+#!/usr/bin/env bash
+# G5's gate for P4a: the Espryt do-not-touch list is LITERAL - SEVENTEEN regions across THREE
+# files stay byte-identical after P4a.
+#
+# WHAT G5 CLAIMS, and why a diff of the files cannot say it. ARCHITECTURE.md:318 is the Espryt
+# do-not-touch list and :321 names the ONE item moved out of it (the sub-rect upload decision and
+# the stride computation, which is P4a's D-D3/D-D6 subject). P3a made the buffer half of that list
+# literal with a sha gate over eleven functions in Managers.cpp (scripts/p3a_untouched_regions.sh);
+# P4a rewrites the rest of Managers.cpp, DirectGLES.cpp and Utils.cpp by design - the twins become
+# handle-shaped, the descriptors replace the frontend reads - so the files' diffs are large and say
+# nothing about whether the ring, the permutation, the depth/stencil sampling core or the format
+# caveat moved. This gate extracts the seventeen BODIES and compares them on their own.
+#
+# THE SEVENTEEN. P3a's eleven are carried forward unchanged (BRIEF-P4A.md D-N: "P4a must not touch
+# any of the eleven"), so this script is a superset of its parent and the two run side by side -
+# the parent keeps answering P3a's question against P3a's base ref, this one answers P4a's.
+#
+#   -- P3a's eleven, in Managers.cpp, in the parent's fixed order --
+#   IsPoolable                     takes the server-side resource, never the frontend object
+#   EnrollIntoPool                 the retireSerial = CurrentFrameSerial() + 1 stamp is load-bearing
+#   AcquireFromPool                hands back only entries whose GPU work is complete
+#   TrimBufferPool                 called once per frame from Present
+#   ClearBufferPool                context loss
+#   ProcessDeferredBufferReleases  drained per draw, fast-outs on an atomic flag
+#   CreateRingStorage              glBufferStorageEXT + persistent|coherent, retires at serial + 1
+#   RingAvailable                  self-heals a stale context generation
+#   RingAllocate                   the fast path on the hot upload route
+#   FlushPendingRangesNow          the three-tier drain, pull arm
+#   FlushPendingRangesFrom         the SAME three-tier drain, on the arm that ships (ID-15). Born
+#                                  in P3a, so its baseline is PINNED, not read from <ref-a>
+#
+#   -- P4a's six (BRIEF-P4A.md D-N), all of which predate the phase --
+#   StageBlocksIntoUnpackRing      Managers.cpp: the unpack-PBO staging repack. It is what makes the
+#                                  ring path issue NO glPixelStorei, and the +6 ms/frame Mali cliff
+#                                  lives on the other side of it
+#   UnpackRingAvailable            Managers.cpp: honours Features.EsprytDisableUnpackRing and
+#                                  self-heals a stale context generation
+#   UnpackRingAllocate             Managers.cpp: on the hot upload route
+#   RecomputeBackendColorSlots     Managers.cpp: the attachment permutation - three passes plus the
+#                                  forced ~0 version memo on every moved attachment; removing the
+#                                  empty-point detach breaks the invariant (Managers.cpp:7651-7658)
+#   DepthStencilSamplingReadImpl   DirectGLES.cpp: the D24S8 sampling-emulation core (memory
+#                                  better-clouds-fullmode), entered from :8617 and :8721
+#   ShouldUseCaveatTextureFormat   Utils.cpp: the format handler P4a's InternalFormat descriptors
+#                                  feed; a change here silently changes what every texture is
+#                                  allocated as
+#
+# TWO THINGS THIS SCRIPT ADDS TO ITS PARENT, AND NOTHING ELSE (BRIEF-P4A.md D-N: "keeps every other
+# property of its parent verbatim"):
+#
+#   1. A PER-REGION SOURCE PATH. The parent's SOURCE_PATH is a single file (:85); the seventeen live
+#      in three. Each row below carries its own path and the extractor reads each file once.
+#   2. A REGION KIND. [declared deviation, see DEVIATIONS below] Sixteen of the seventeen are
+#      FUNCTIONS. `DepthStencilSamplingReadImpl` is a NAMESPACE (DirectGLES.cpp:8117-8578) - the
+#      brief's D-N table names it as though it were a function, and the parent's extractor, which
+#      finds a definition as the one `<name> (` whose closing paren is followed by `{`, finds ZERO
+#      definitions of it and exits 2 forever. Hashing the whole namespace block is also the
+#      stronger reading of "the D24S8 sampling-emulation CORE": the core is the ~460-line block of
+#      staging, conversion and readback, not any one function inside it.
+#
+# Everything else is the parent verbatim, and deliberately so:
+#
+# HOW A BODY IS EXTRACTED. The file is masked first - comments, string, char and raw-string
+# literals are replaced by spaces of the same length, so a brace or a parenthesis inside one can
+# never be counted - and the DEFINITION is then found as the one occurrence of `<name> (` whose
+# closing parenthesis is followed (past qualifiers like const/noexcept) by `{`. That is what tells
+# a definition from a forward declaration and from a call site: a call's `)` is followed by `)`,
+# `;` or `,`, never by `{`. A NAMESPACE row is found as the one occurrence of `namespace <name>`
+# followed by `{`. The body is then brace matched in the masked text and hashed from the ORIGINAL
+# text, so a comment change inside one of these is a difference too - which is deliberate: the
+# claim is "byte-identical", and a comment that stopped describing what the code does is exactly
+# the kind of drift a "verbatim move" is supposed to be checked for.
+#
+# THE HASH'S EXACT EXTENT, so that the claim is not read wider than it is (review F-m3, inherited
+# from the parent verbatim): it starts at the beginning of the LINE THAT CARRIES THE NAME and ends
+# at the region's closing brace. A return type, an attribute or a template header sitting on an
+# EARLIER line of a multi-line signature is therefore OUTSIDE the hash, and changing one of those
+# alone does not move this gate. The end IS covered - the self-test's tail controls below prove
+# the extent reaches the closing brace - and G1's symbol report is what catches a signature that
+# changed shape.
+#
+# Exactly one definition must be found per name. Zero or two is exit 2 (could not run), never a
+# silent pass: a rename this gate could not follow must not read as "nothing moved". Two is the
+# expected shape of a #if/#else pair that re-spells one of these bodies beside an untouched copy -
+# a finding, not a limitation, because two ladders drift (ID-11, ID-15).
+#
+# A SHARED TEMPLATE OVER AN ACCESSOR INTERFACE IS REJECTED (ID-13, MEASUREMENTS.md:521): it resizes
+# pull symbols and breaks G1. If a P4a arm needs a variant of one of the seventeen it gets its own
+# `#if MOBILEGL_PIPE_PUSH` function with its own name and its own pinned sha - the
+# FlushPendingRangesFrom shape.
+#
+# Usage:
+#   scripts/p4a_untouched_regions.sh <ref-a> <ref-b>   compare the seventeen at two git refs
+#   scripts/p4a_untouched_regions.sh <ref>             print the seventeen shas at one ref (a
+#                                                      baseline capture: ... > p4a-before.sha)
+#   scripts/p4a_untouched_regions.sh --self-test       prove the comparison can go red
+#
+# stdout is always the sha list - `<sha256>  <region>`, one per line, in the fixed order above - so
+# a baseline capture is a plain redirect. Everything else goes to stderr.
+#
+# Both arguments are GIT REFS: the gate is about what landed, so an uncommitted edit is invisible
+# by design. Use HEAD after committing, which is what D.1 and the CI row do.
+#
+# Exit codes: 0 the seventeen are identical at both refs (or a single ref was listed);
+#             1 at least one moved - the first one in the fixed order is named on stderr;
+#             2 the gate could not run: a bad ref, a missing file, a name that is not defined
+#               exactly once, or a self-test whose control failed to trip.
+#
+# DEVIATIONS from BRIEF-P4A.md D-N, both declared here rather than in a commit message so that the
+# next reader of this file meets them:
+#   D-N/1  the namespace region kind, above.
+#   D-N/2  the PINNED baseline is CONSULTED UNCONDITIONALLY for FlushPendingRangesFrom, where the
+#          parent consults it only when <ref-a> does not define the function. D-N says that row is
+#          compared "against its pinned 3e298c9a sha", and at P4a's base ref the function DOES
+#          exist - so the parent's fallback would silently never fire and the pin would stop being
+#          the baseline the brief names. Both readings agree on this tree (measured: the body at
+#          37da3c3a hashes to the pinned value); where they would ever disagree, this script says
+#          so on stderr and keeps the PIN, because the pin is the reviewed text.
+set -u -o pipefail
+
+# One row per region: <name>@<kind>@<path>. The ORDER is the fixed order the sha list is printed
+# in and the order `compare_lists` names the first mover from; P3a's eleven keep their parent's
+# positions so a reader can diff the two scripts' outputs.
+REGIONS="\
+IsPoolable@function@MobileGL/MG_Backend/DirectGLES/Managers.cpp
+EnrollIntoPool@function@MobileGL/MG_Backend/DirectGLES/Managers.cpp
+AcquireFromPool@function@MobileGL/MG_Backend/DirectGLES/Managers.cpp
+TrimBufferPool@function@MobileGL/MG_Backend/DirectGLES/Managers.cpp
+ClearBufferPool@function@MobileGL/MG_Backend/DirectGLES/Managers.cpp
+ProcessDeferredBufferReleases@function@MobileGL/MG_Backend/DirectGLES/Managers.cpp
+CreateRingStorage@function@MobileGL/MG_Backend/DirectGLES/Managers.cpp
+RingAvailable@function@MobileGL/MG_Backend/DirectGLES/Managers.cpp
+RingAllocate@function@MobileGL/MG_Backend/DirectGLES/Managers.cpp
+FlushPendingRangesNow@function@MobileGL/MG_Backend/DirectGLES/Managers.cpp
+FlushPendingRangesFrom@function@MobileGL/MG_Backend/DirectGLES/Managers.cpp
+StageBlocksIntoUnpackRing@function@MobileGL/MG_Backend/DirectGLES/Managers.cpp
+UnpackRingAvailable@function@MobileGL/MG_Backend/DirectGLES/Managers.cpp
+UnpackRingAllocate@function@MobileGL/MG_Backend/DirectGLES/Managers.cpp
+RecomputeBackendColorSlots@function@MobileGL/MG_Backend/DirectGLES/Managers.cpp
+DepthStencilSamplingReadImpl@namespace@MobileGL/MG_Backend/DirectGLES/DirectGLES.cpp
+ShouldUseCaveatTextureFormat@function@MobileGL/MG_Backend/DirectGLES/Utils.cpp"
+
+EXPECTED_FUNCTION_COUNT=17
+
+# The one region born in P3a, so there is no body at P4a's base ref that this phase reviewed: its
+# baseline is the sha captured at 3e298c9a, the commit at which the two-arm shape was reviewed and
+# accepted (ID-15). See DEVIATIONS D-N/2 for why it is consulted unconditionally.
+PINNED_FUNCTIONS="FlushPendingRangesFrom"
+PINNED_BASELINE_REF=3e298c9a
+PINNED_SHA_FlushPendingRangesFrom=37fc94ffc5991923d222d585daa3af6511d2352d255623026ce35a3b6963c4a6
+
+# The regions the self-test perturbs, one negative control each. FOUR, exactly as D-N requires, and
+# each is a different shape so that a control which only ever perturbed the easy one cannot leave
+# the others unproven:
+#   ClearBufferPool             P3a's easy control - small, no forward declaration, no overload, so
+#                               a failure there is about the COMPARISON rather than the extraction
+#   FlushPendingRangesNow       P3a's hard control - the longest body in the set, three nested
+#                               tiers, its own early returns, and one of a PAIR of identically
+#                               shaped bodies in two preprocessor arms
+#   RecomputeBackendColorSlots  P4a's method-shaped control: a member function spelled
+#                               `BackendFramebufferObject::RecomputeBackendColorSlots(` with a
+#                               multi-line signature and a call site of its own, so a naive
+#                               extraction picks the wrong occurrence
+#   StageBlocksIntoUnpackRing   P4a's static-in-an-anonymous-namespace control, on the hot upload
+#                               route, and the one whose file position sits between two other
+#                               protected bodies
+SELF_TEST_FUNCTIONS="ClearBufferPool FlushPendingRangesNow RecomputeBackendColorSlots StageBlocksIntoUnpackRing"
+
+say() { echo "[p4a-untouched] $*" >&2; }
+
+REPO_ROOT=$(cd "$(dirname "$0")/.." && pwd) || exit 2
+cd "$REPO_ROOT" || exit 2
+
+WORK_DIR=$(mktemp -d) || exit 2
+trap 'rm -rf "$WORK_DIR"' EXIT
+
+# Every distinct source path the rows name, in first-appearance order.
+region_paths() {
+  printf '%s\n' "$REGIONS" | awk -F@ '!seen[$3]++ { print $3 }'
+}
+
+# The extractor. Three modes, all over a SPEC FILE of `<name>\t<kind>\t<file>` rows so that the
+# self-test can drive it without inventing a commit: `extract` prints one `<sha>  <name>` line per
+# row in spec order, `perturb` writes a copy of one file with one statement inserted at the top of
+# one region's body, `count` is unused by the shell and kept out.
+PY=$WORK_DIR/extract.py
+cat > "$PY" <<'PYTHON'
+import hashlib
+import re
+import sys
+
+
+def mask(text):
+    """Comments and literals replaced by spaces of the same length, offsets preserved."""
+    out = list(text)
+    i, n = 0, len(text)
+    while i < n:
+        c = text[i]
+        if c == '/' and i + 1 < n and text[i + 1] == '/':
+            while i < n and text[i] != '\n':
+                out[i] = ' '
+                i += 1
+        elif c == '/' and i + 1 < n and text[i + 1] == '*':
+            out[i] = out[i + 1] = ' '
+            i += 2
+            while i + 1 < n and not (text[i] == '*' and text[i + 1] == '/'):
+                if text[i] != '\n':
+                    out[i] = ' '
+                i += 1
+            if i + 1 < n:
+                out[i] = out[i + 1] = ' '
+                i += 2
+        elif c == 'R' and i + 1 < n and text[i + 1] == '"':
+            # R"delim( ... )delim" - a shader source is one of these, and it is full of braces.
+            close = text.find('(', i + 2)
+            if close < 0:
+                i += 1
+                continue
+            delim = text[i + 2:close]
+            end = text.find(')' + delim + '"', close)
+            end = n if end < 0 else end + len(delim) + 2
+            for j in range(i, end):
+                if text[j] != '\n':
+                    out[j] = ' '
+            i = end
+        elif c == "'" and i > 0 and (text[i - 1].isdigit() or
+                                     (text[i - 1] in 'abcdefABCDEF' and i > 1 and
+                                      text[i - 2] in "0123456789abcdefABCDEFxX")):
+            # A C++14 DIGIT SEPARATOR (16'777'216, 0xff'ff), not a char literal. Treating it as one
+            # would blank forward to the next apostrophe - which can be a whole function away, in a
+            # comment - and silently swallow a brace, shifting a body's extent with no diagnostic.
+            i += 1
+        elif c in '"\'':
+            quote = c
+            out[i] = ' '
+            i += 1
+            while i < n and text[i] != quote:
+                if text[i] == '\\' and i + 1 < n:
+                    out[i] = ' '
+                    i += 1
+                if text[i] != '\n':
+                    out[i] = ' '
+                i += 1
+            if i < n:
+                out[i] = ' '
+                i += 1
+        else:
+            i += 1
+    return ''.join(out)
+
+
+def match_forward(masked, start, opener, closer):
+    depth = 0
+    for i in range(start, len(masked)):
+        if masked[i] == opener:
+            depth += 1
+        elif masked[i] == closer:
+            depth -= 1
+            if depth == 0:
+                return i
+    return -1
+
+
+def find_function(text, masked, name):
+    """Every (begin, end) at which `name` is DEFINED as a function."""
+    hits = []
+    for m in re.finditer(r'\b' + re.escape(name) + r'\s*\(', masked):
+        open_paren = m.end() - 1
+        close_paren = match_forward(masked, open_paren, '(', ')')
+        if close_paren < 0:
+            continue
+        tail = masked[close_paren + 1:close_paren + 96]
+        # Past whatever qualifiers a definition may carry; anything else means this was a call
+        # or a declaration.
+        stripped = re.sub(r'^(\s|const\b|noexcept\b|override\b|final\b)*', '', tail)
+        if not stripped.startswith('{'):
+            continue
+        brace = masked.index('{', close_paren)
+        end = match_forward(masked, brace, '{', '}')
+        if end < 0:
+            continue
+        begin = text.rfind('\n', 0, m.start()) + 1
+        hits.append((begin, end + 1))
+    return hits
+
+
+def find_namespace(text, masked, name):
+    """Every (begin, end) at which `name` is DEFINED as a namespace.
+
+    P4a's DepthStencilSamplingReadImpl is a namespace, not a function (DirectGLES.cpp:8117-8578):
+    the D24S8 sampling-emulation CORE is the whole block, and a function-shaped search finds no
+    definition of it at all. The closing `} // namespace <name>` comment is masked away by the
+    time this runs, so the extent is decided by brace matching exactly as a function's is - and a
+    USE of the namespace (`DepthStencilSamplingReadImpl::Read(...)`) is not matched, because the
+    `namespace` keyword is not in front of it.
+    """
+    hits = []
+    for m in re.finditer(r'\bnamespace\s+' + re.escape(name) + r'\b', masked):
+        rest = masked[m.end():m.end() + 96]
+        if not rest.lstrip().startswith('{'):
+            continue
+        brace = masked.index('{', m.end())
+        end = match_forward(masked, brace, '{', '}')
+        if end < 0:
+            continue
+        begin = text.rfind('\n', 0, m.start()) + 1
+        hits.append((begin, end + 1))
+    return hits
+
+
+def find_definition(text, masked, name, kind):
+    if kind == 'namespace':
+        return find_namespace(text, masked, name)
+    return find_function(text, masked, name)
+
+
+def read_spec(path):
+    rows = []
+    with open(path, encoding='utf-8') as spec:
+        for line in spec:
+            line = line.rstrip('\n')
+            if not line:
+                continue
+            name, kind, source = line.split('\t')
+            rows.append((name, kind, source))
+    return rows
+
+
+class Sources(object):
+    """Each file read and masked once, however many regions name it."""
+
+    def __init__(self):
+        self.cache = {}
+
+    def get(self, path):
+        if path not in self.cache:
+            text = open(path, encoding='utf-8', newline='').read()
+            self.cache[path] = (text, mask(text))
+        return self.cache[path]
+
+
+def extract(rows):
+    sources = Sources()
+    out, problems = [], []
+    for name, kind, source in rows:
+        try:
+            text, masked = sources.get(source)
+        except OSError as err:
+            problems.append('%s: cannot read %s (%s)' % (name, source, err))
+            continue
+        hits = find_definition(text, masked, name, kind)
+        if len(hits) != 1:
+            problems.append('%s: expected exactly one %s definition in %s, found %d'
+                            % (name, kind, source, len(hits)))
+            if len(hits) > 1:
+                # The expected shape of this failure, and it is a FINDING rather than a limitation:
+                # a `#if MOBILEGL_PIPE_PUSH` arm that re-spells one of these bodies beside an
+                # untouched `#else` copy satisfies G1 (the pull build's text did not move) and
+                # defeats G5 (the push build compiles a second copy that can drift). The gate
+                # cannot say which of the two is "the" body, and must not pick one.
+                for begin, end in hits:
+                    problems.append('  ...definition at line %d, %d lines'
+                                    % (text[:begin].count('\n') + 1,
+                                       text[:end].count('\n') - text[:begin].count('\n') + 1))
+                problems.append('  the P4a arm must CALL the untouched %s, not carry a copy of it: '
+                                'two ladders drift (BRIEF-P4A.md D-N, ID-11, ID-15)' % name)
+            continue
+        begin, end = hits[0]
+        body = text[begin:end]
+        out.append((hashlib.sha256(body.encode('utf-8')).hexdigest(), name))
+    return out, problems
+
+
+def perturb(rows, target, src, dst, where='head'):
+    """Insert one line into a region's body, at its HEAD or at its TAIL.
+
+    TWO POSITIONS, AND THE SECOND ONE IS REVIEW FINDING F-m2. Every control used to insert at the
+    very first byte after the opening brace, so all four of them would still have tripped if
+    find_definition() returned an extent that stopped short of the closing brace - nothing in the
+    self-test proved that a region reaches its own end, and an extractor that hashed all but the
+    last statement of every body would have passed the whole self-test while being blind to a
+    change in that statement. The `tail` position inserts immediately BEFORE the closing brace,
+    which is the byte such an extractor would have dropped.
+    """
+    for name, kind, source in rows:
+        if name != target:
+            continue
+        text = open(src, encoding='utf-8', newline='').read()
+        masked = mask(text)
+        hits = find_definition(text, masked, name, kind)
+        if len(hits) != 1:
+            sys.stderr.write('[p4a-untouched] cannot perturb %s: %d definitions\n'
+                             % (target, len(hits)))
+            return 2
+        begin, end = hits[0]
+        if where == 'tail':
+            # end is one PAST the closing brace (find_function / find_namespace both return
+            # `match_forward(...) + 1`), so end - 1 is the brace itself and this lands inside the
+            # body, one character before it ends.
+            note = '\n            // p4a_untouched_regions.sh --self-test: a body whose TAIL moved.\n'
+            patched = text[:end - 1] + note + text[end - 1:]
+        else:
+            # The opening brace is located in the MASKED text and then used as an offset into the
+            # original: a brace inside a comment or a string on the signature line would otherwise
+            # send the perturbation somewhere that is not the body, and the control would be
+            # proving the wrong thing. Offsets are identical between the two by construction
+            # (mask() preserves length).
+            brace = masked.index('{', begin)
+            patched = (text[:brace + 1] +
+                       '\n            // p4a_untouched_regions.sh --self-test: a body that MOVED.\n' +
+                       text[brace + 1:])
+        open(dst, 'w', encoding='utf-8', newline='').write(patched)
+        return 0
+    sys.stderr.write('[p4a-untouched] %s is not one of the regions\n' % target)
+    return 2
+
+
+def main(argv):
+    # The sha list is parsed by awk, and on Windows (Git Bash, MSYS python) text-mode stdout
+    # translates '\n' into CRLF - after which `$2 == n` never matches and the gate exits 1 on an
+    # untouched tree. Linux CI never saw it; a developer running the gate locally always did.
+    if hasattr(sys.stdout, 'reconfigure'):
+        sys.stdout.reconfigure(newline='\n')
+    mode = argv[1]
+    rows = read_spec(argv[2])
+    if mode == 'extract':
+        found, problems = extract(rows)
+        for problem in problems:
+            sys.stderr.write('[p4a-untouched] %s\n' % problem)
+        for sha, name in found:
+            sys.stdout.write('%s  %s\n' % (sha, name))
+        return 2 if problems else 0
+    if mode == 'perturb':
+        return perturb(rows, argv[3], argv[4], argv[5], argv[6] if len(argv) > 6 else 'head')
+    sys.stderr.write('[p4a-untouched] unknown mode %r\n' % mode)
+    return 2
+
+
+sys.exit(main(sys.argv))
+PYTHON
+
+# Write a spec file whose rows point at the blobs in "$2" (a directory holding one file per
+# region path, named by a sanitised path so two files of the same basename could never collide).
+blob_name() { printf '%s' "$1" | tr '/' '_'; }
+
+write_spec() {
+  local dir=$1 spec=$2 row name kind source
+  : > "$spec"
+  printf '%s\n' "$REGIONS" | while IFS='@' read -r name kind source; do
+    [ -n "$name" ] || continue
+    printf '%s\t%s\t%s/%s\n' "$name" "$kind" "$dir" "$(blob_name "$source")" >> "$spec"
+  done
+}
+
+# Materialise every region source at a git ref into "$2".
+checkout_ref() {
+  local ref=$1 dir=$2 source
+  mkdir -p "$dir" || return 2
+  for source in $(region_paths); do
+    if ! git show "$ref:$source" > "$dir/$(blob_name "$source")" 2>"$WORK_DIR/show.err"; then
+      say "cannot read $source at '$ref':"
+      sed 's/^/[p4a-untouched]   /' "$WORK_DIR/show.err" >&2
+      return 2
+    fi
+  done
+  return 0
+}
+
+# Extract at a git ref into "$WORK_DIR/$2.sha". Every region must be defined exactly once there;
+# this is the side the gate is ABOUT (<ref-b>, and the single-ref listing's ref).
+extract_ref() {
+  local ref=$1 out=$2
+  checkout_ref "$ref" "$WORK_DIR/$out" || return 2
+  write_spec "$WORK_DIR/$out" "$WORK_DIR/$out.spec"
+  python3 "$PY" extract "$WORK_DIR/$out.spec" > "$WORK_DIR/$out.sha"
+  return $?
+}
+
+# The BASELINE side (<ref-a>). The sixteen ordinary regions are extracted strictly, so a rename of
+# one of THOSE is exit 2 rather than a silently short list. FlushPendingRangesFrom then takes the
+# PINNED sha (DEVIATIONS D-N/2) whether or not <ref-a> defines it, and a <ref-a> that defines it
+# DIFFERENTLY is reported - loudly - because the two answers disagreeing is itself a finding.
+extract_baseline() {
+  local ref=$1 out=$2 name pinned atRef
+  checkout_ref "$ref" "$WORK_DIR/$out" || return 2
+  write_spec "$WORK_DIR/$out" "$WORK_DIR/$out.spec.all"
+  # The strict pass, minus the pinned rows.
+  cp -f "$WORK_DIR/$out.spec.all" "$WORK_DIR/$out.spec" || return 2
+  for name in $PINNED_FUNCTIONS; do
+    grep -v "^$name$(printf '\t')" "$WORK_DIR/$out.spec" > "$WORK_DIR/$out.spec.tmp" || true
+    mv -f "$WORK_DIR/$out.spec.tmp" "$WORK_DIR/$out.spec" || return 2
+  done
+  if ! python3 "$PY" extract "$WORK_DIR/$out.spec" > "$WORK_DIR/$out.sha" 2>"$WORK_DIR/$out.err"; then
+    say "the baseline ref '$ref' does not define the sixteen unpinned regions exactly once each:"
+    sed 's/^/[p4a-untouched]   /' "$WORK_DIR/$out.err" >&2
+    return 2
+  fi
+  for name in $PINNED_FUNCTIONS; do
+    eval "pinned=\$PINNED_SHA_$name"
+    if [ -z "$pinned" ] || [ "$pinned" = "PLACEHOLDER_SHA" ]; then
+      say "$name has no pinned baseline sha; that row cannot be compared"
+      return 2
+    fi
+    grep "^$name$(printf '\t')" "$WORK_DIR/$out.spec.all" > "$WORK_DIR/$out.spec.pinned" || true
+    atRef=$(python3 "$PY" extract "$WORK_DIR/$out.spec.pinned" 2>/dev/null | awk '{ print $1 }')
+    if [ -n "$atRef" ] && [ "$atRef" != "$pinned" ]; then
+      say "NOTE: $name IS defined at '$ref' and hashes $atRef, which is NOT the sha pinned in this"
+      say "  script ($pinned, captured at $PINNED_BASELINE_REF). The PIN is what is compared - it is"
+      say "  the reviewed text (ID-15) - but the two disagreeing means the push ladder moved between"
+      say "  $PINNED_BASELINE_REF and '$ref' without this gate being re-pinned. Re-pin deliberately or"
+      say "  revert; do not leave them disagreeing."
+    fi
+    printf '%s  %s\n' "$pinned" "$name" >> "$WORK_DIR/$out.sha"
+  done
+  # ...and put the list back into the FIXED ORDER (review F-m1). The pinned rows were stripped out
+  # of the spec above and appended here, so without this the baseline side emits them LAST while
+  # extract_ref emits everything in REGIONS order. The gate itself never noticed - compare_lists
+  # looks rows up by name - but the documented capture workflow did: the header promises "stdout is
+  # always the sha list ... in the fixed order above - so a baseline capture is a plain redirect",
+  # and a baseline captured that way then diffed against a two-ref stdout showed seven spurious
+  # differences purely from row order.
+  reorder_sha_list "$WORK_DIR/$out.sha" || return 2
+  return 0
+}
+
+# Rewrite a `<sha>  <region>` list in REGIONS order, in place. Rows whose name is not in REGIONS
+# would be a bug in the caller rather than a difference, so they are kept at the end where they are
+# visible instead of being dropped.
+reorder_sha_list() {
+  local file=$1 name
+  : > "$file.ordered" || return 2
+  printf '%s\n' "$REGIONS" | awk -F@ '{ print $1 }' > "$WORK_DIR/reorder.names" || return 2
+  while read -r name; do
+    [ -n "$name" ] || continue
+    awk -v n="$name" '$2 == n { print }' "$file" >> "$file.ordered" || return 2
+  done < "$WORK_DIR/reorder.names"
+  awk 'NR == FNR { known[$0] = 1; next } !($2 in known) { print }' \
+      "$WORK_DIR/reorder.names" "$file" >> "$file.ordered" || return 2
+  mv -f "$file.ordered" "$file" || return 2
+  return 0
+}
+
+# Compare two sha lists. Prints the first region that moved, in REGIONS order.
+compare_lists() {
+  local a=$1 b=$2 labelA=$3 labelB=$4 moved=0 name shaA shaB
+  printf '%s\n' "$REGIONS" | awk -F@ '{ print $1 }' > "$WORK_DIR/order"
+  while read -r name; do
+    [ -n "$name" ] || continue
+    shaA=$(awk -v n="$name" '$2 == n { print $1 }' "$a")
+    shaB=$(awk -v n="$name" '$2 == n { print $1 }' "$b")
+    if [ "$shaA" != "$shaB" ]; then
+      if [ "$moved" -eq 0 ]; then
+        say "FIRST REGION THAT MOVED: $name"
+        say "  $labelA ${shaA:-<not found>}"
+        say "  $labelB ${shaB:-<not found>}"
+        say "  G5 (ARCHITECTURE.md:318, :321, :515) says the Espryt do-not-touch list is literal:"
+        say "  P3a's buffer pool, deferred-release drain, three rings and BOTH arms of the three-tier"
+        say "  flush drain, plus P4a's unpack-PBO staging repack and its two ring helpers, the"
+        say "  attachment permutation, the D24S8 sampling-emulation core and the format-caveat"
+        say "  handler, all move VERBATIM. If this change is intended it is not a P4a change and it"
+        say "  needs its own commit and its own reason; if it is not, revert the body. A P4a arm that"
+        say "  carries its own COPY of one of these beside an untouched one is the same finding: the"
+        say "  new arm must CALL the untouched region, not re-spell it."
+      else
+        say "also moved: $name"
+      fi
+      moved=$((moved + 1))
+    fi
+  done < "$WORK_DIR/order"
+  return $((moved > 0 ? 1 : 0))
+}
+
+# --- self-test ------------------------------------------------------------------------------
+# A gate that always says "identical" and a gate that is working produce the same green, so the
+# comparison has to be shown failing. Both controls run: the POSITIVE ones (an untouched copy
+# compares equal; an edit OUTSIDE the regions is invisible) rule out a comparison that reports
+# every region as moved, and the eight NEGATIVE ones - D-N's four regions, each perturbed at the
+# HEAD of its body and again at its TAIL - rule out both the comparison that never reports any and
+# the extraction whose extent stops before the closing brace (F-m2).
+if [ "${1:-}" = "--self-test" ]; then
+  [ $# -eq 1 ] || { say "--self-test takes no other arguments"; exit 2; }
+  mkdir -p "$WORK_DIR/pristine" || exit 2
+  for source in $(region_paths); do
+    [ -f "$source" ] || { say "$source is not in this tree"; exit 2; }
+    cp -f "$source" "$WORK_DIR/pristine/$(blob_name "$source")" || exit 2
+  done
+  write_spec "$WORK_DIR/pristine" "$WORK_DIR/pristine.spec"
+  if ! python3 "$PY" extract "$WORK_DIR/pristine.spec" > "$WORK_DIR/pristine.sha"; then
+    say "the extractor could not read the $EXPECTED_FUNCTION_COUNT regions out of the working tree"
+    exit 2
+  fi
+  found=$(wc -l < "$WORK_DIR/pristine.sha")
+  if [ "$found" -ne "$EXPECTED_FUNCTION_COUNT" ]; then
+    say "extracted $found regions, expected $EXPECTED_FUNCTION_COUNT"
+    exit 2
+  fi
+  say "positive control: $EXPECTED_FUNCTION_COUNT regions extracted from the working tree"
+
+  cp -r "$WORK_DIR/pristine" "$WORK_DIR/copy" || exit 2
+  write_spec "$WORK_DIR/copy" "$WORK_DIR/copy.spec"
+  python3 "$PY" extract "$WORK_DIR/copy.spec" > "$WORK_DIR/copy.sha" || exit 2
+  if ! compare_lists "$WORK_DIR/pristine.sha" "$WORK_DIR/copy.sha" "pristine" "copy" 2>/dev/null; then
+    say "POSITIVE CONTROL FAILED: an untouched copy compared as MOVED. The comparison is reporting"
+    say "differences that are not there, so its verdict means nothing in either direction."
+    exit 2
+  fi
+  say "positive control: an untouched copy compares equal"
+
+  # The second positive control, and it is the one that matters for P4a: the rest of these three
+  # files IS going to be rewritten (the twins become handle-shaped, the descriptors replace the
+  # frontend reads), so a gate that fired on any edit to them would have to be switched off in the
+  # same week it landed. An edit outside the seventeen must be invisible here - in EVERY file, so
+  # that a per-file extraction bug cannot hide behind the one file that was probed.
+  cp -r "$WORK_DIR/pristine" "$WORK_DIR/outside" || exit 2
+  for source in $(region_paths); do
+    { echo "// p4a_untouched_regions.sh --self-test: an edit OUTSIDE the seventeen regions."; \
+      cat "$WORK_DIR/pristine/$(blob_name "$source")"; } > "$WORK_DIR/outside/$(blob_name "$source")"
+  done
+  write_spec "$WORK_DIR/outside" "$WORK_DIR/outside.spec"
+  python3 "$PY" extract "$WORK_DIR/outside.spec" > "$WORK_DIR/outside.sha" || exit 2
+  if ! compare_lists "$WORK_DIR/pristine.sha" "$WORK_DIR/outside.sha" "pristine" "outside" \
+       2>/dev/null; then
+    say "POSITIVE CONTROL FAILED: an edit OUTSIDE the seventeen regions was reported as one of them"
+    say "moving. This gate would fire on every P4a commit to these three files and would have to be"
+    say "silenced, which is the same as not having it."
+    exit 2
+  fi
+  say "positive control: an edit outside the seventeen regions is invisible, in all three files"
+
+  # TWO negative controls per SELF_TEST_FUNCTIONS entry - one at the HEAD of the body and one at
+  # its TAIL. Each is run on its own, from the pristine copy, so the message it produces has to
+  # NAME that region: a control that only proved "some region moved" would not distinguish "this
+  # row is compared" from "this row is extracted as an empty range and every comparison of it is
+  # vacuous".
+  #
+  # THE TAIL HALF IS REVIEW FINDING F-m2. With head-only controls, an extraction that returned an
+  # extent stopping short of the closing brace would still have tripped all four - the inserted
+  # line is at the very first byte of the body - so nothing here proved that a region reaches its
+  # own end, and a change to the LAST statement of a protected body would have been invisible to a
+  # gate whose self-test was fully green. The tail control inserts immediately before the closing
+  # brace, which is exactly the byte such an extractor would have dropped.
+  controls=0
+  for target in $SELF_TEST_FUNCTIONS; do
+    targetSource=$(printf '%s\n' "$REGIONS" | awk -F@ -v n="$target" '$1 == n { print $3 }')
+    [ -n "$targetSource" ] || { say "$target is not one of the regions"; exit 2; }
+    for position in head tail; do
+      rm -rf "$WORK_DIR/perturbed"
+      cp -r "$WORK_DIR/pristine" "$WORK_DIR/perturbed" || exit 2
+      write_spec "$WORK_DIR/perturbed" "$WORK_DIR/perturbed.spec"
+      python3 "$PY" perturb "$WORK_DIR/perturbed.spec" "$target" \
+          "$WORK_DIR/pristine/$(blob_name "$targetSource")" \
+          "$WORK_DIR/perturbed/$(blob_name "$targetSource")" "$position" || exit 2
+      python3 "$PY" extract "$WORK_DIR/perturbed.spec" > "$WORK_DIR/perturbed.sha" || exit 2
+      if compare_lists "$WORK_DIR/pristine.sha" "$WORK_DIR/perturbed.sha" "pristine" "perturbed" \
+           2> "$WORK_DIR/perturbed.err"; then
+        say "NEGATIVE CONTROL DID NOT TRIP: $target's body was changed at its $position and the"
+        say "comparison still reported every region as identical. This gate cannot go red for the"
+        say "reason it exists, so every green it has ever printed means nothing."
+        if [ "$position" = tail ]; then
+          say "  A TAIL control that does not trip while the head one does means the extracted"
+          say "  extent stops before the closing brace: the last statement of every protected body"
+          say "  is outside the hash and can be rewritten silently."
+        fi
+        exit 2
+      fi
+      if ! grep -q "FIRST REGION THAT MOVED: $target" "$WORK_DIR/perturbed.err"; then
+        say "NEGATIVE CONTROL TRIPPED FOR THE WRONG REASON: the comparison went red but did not name"
+        say "$target as the first region that moved ($position control). It said:"
+        sed 's/^/[p4a-untouched]   /' "$WORK_DIR/perturbed.err" >&2
+        exit 2
+      fi
+      controls=$((controls + 1))
+      say "negative control $controls: a perturbed $target body ($position) is reported, and named"
+    done
+  done
+  if [ "$controls" -ne 8 ]; then
+    say "expected EIGHT negative controls (BRIEF-P4A.md D-N's four regions, each at its head and at"
+    say "its tail), ran $controls"
+    exit 2
+  fi
+  say "self-test passed: $controls negative controls, all tripped and all named"
+  exit 0
+fi
+
+# --- the gate -------------------------------------------------------------------------------
+case $# in
+  1)
+    extract_baseline "$1" one || exit 2
+    cat "$WORK_DIR/one.sha"
+    say "listed the $EXPECTED_FUNCTION_COUNT regions at $1"
+    exit 0
+    ;;
+  2) ;;
+  *)
+    say "usage: $0 <ref-a> <ref-b> | $0 <ref> | $0 --self-test"
+    exit 2
+    ;;
+esac
+
+extract_baseline "$1" a || exit 2
+extract_ref "$2" b || exit 2
+cat "$WORK_DIR/b.sha"
+
+if compare_lists "$WORK_DIR/a.sha" "$WORK_DIR/b.sha" "$1" "$2"; then
+  say "the $EXPECTED_FUNCTION_COUNT pool / ring / unpack-staging / attachment-permutation /"
+  say "depth-stencil-sampling / format-caveat regions are byte-identical between $1 and $2"
+  exit 0
+fi
+exit 1