[Fix, Test] (Pipe): mix the program identity into the shader-image shutter's plain arm - the per-program counter is equal across programs and against no program, so a switch never moved the image window and a buffer image never reached set_shader_images (P4a seam F-2, esprytdraw SD-4)

2026-09-09 12:48:32 +09:00 · 2026-09-08 20:28:56 -04:00
parent 0d01405cf8
commit e4579ee80e
4 changed files with 120 additions and 6 deletions
@@ -369,7 +369,15 @@ 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;
@@ -569,5 +569,84 @@ void main() { imageStore(i1, 0, imageLoad(i0, 0) + uvec4(2u, 0u, 0u, 0u)); }
            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());
+        }
+
    } // namespace
 } // namespace MGITest
@@ -300,14 +300,15 @@
    /*   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. AND SINCE THE FABLE     */  \
-    /*     SEAM ROUND (F-1) IT IS BIT 12's TOO: set_sampler_views is resolved for the       */  \
-    /*     program in use, so its shutter mixes the same identity bit 6 reads, and a         */  \
-    /*     glUseProgram alone moves both. Undecided for the same reason as bit 6 (the        */  \
-    /*     taint below), marked the same way.                                                */  \
+    /*     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|NEW_SAMPLER_VIEWS)                        \
+    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) */  \
@@ -417,6 +418,7 @@
 #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
@@ -84,6 +84,7 @@ namespace {
    X(TrackerAggregates, ARenderbufferStorageDefinitionMovesTheFramebufferAggregate) \
    X(TrackerWalk, AProgramSwitchAloneFiresTheSamplerViewBit) \
    X(TrackerWalk, ATextureParameterAloneFiresTheSamplerViewBit) \
+    X(TrackerWalk, AProgramSwitchBetweenEqualImageUnitCountersFiresTheShaderImageBit) \
    X(TrackerAttribPayload, AFloatWriteCarriesTheFloatBitsAndNamesItsClass) \
    X(TrackerAttribPayload, AnIntWriteCarriesTheIntWordsAndNamesItsClass) \
    X(TrackerAttribPayload, AUintWriteCarriesTheUintWordsAndNamesItsClass) \
@@ -826,6 +827,30 @@ namespace {
        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)
    // ===================================================================================