[Perf] (Magma): a wire draw whose image descriptors cannot have moved rebinds its descriptor set with fresh buffer offsets (rd12 monolith 60.5 -> 63.3, inproc 83.7 -> 89.7 fps).

2026-11-07 01:53:24 +09:00 · 2026-10-07 12:15:10 -04:00
parent afcf8d96f9
commit 5788a6023e
2 changed files with 149 additions and 3 deletions
@@ -153,8 +153,9 @@ namespace MobileGL::MG_Backend::DirectVulkan {
    Bool UniformManager::ResolveWireImageDescriptor(
        VkCommandBuffer commandBuffer, const MagmaProgramSource& program,
        const ProgramFactory::VkProgramObject& programObj, Uint32 binding, Uint32 element,
-        Bool storage, VkDescriptorImageInfo& out) const {
+        Bool storage, VkDescriptorImageInfo& out, VkTextureManager::TextureResource** outResource) const {
        out = {};
+        if (outResource != nullptr) *outResource = nullptr;
        auto& state = MG_Pipe::MGPipeApplier();
        const Int baseLocation = programObj.samplerUniformLocationByBinding[binding];
        const Int location = baseLocation + static_cast<Int>(element);
@@ -183,6 +184,7 @@ namespace MobileGL::MG_Backend::DirectVulkan {
        auto* resource = m_textureManager->SyncTextureResourceByHandle(handle, false, storage);
        if (!resource) WireDescriptorFatal("image-resource");
        m_textureManager->FlushPendingUploads();
+        if (outResource != nullptr) *outResource = resource;

        const auto target = static_cast<MG_Pipe::MGPipeResourceTarget>(record.Desc.Target);
        const Bool layerable = WireTargetHasLayers(target);
@@ -630,6 +632,7 @@ namespace MobileGL::MG_Backend::DirectVulkan {
        for (auto& entry : m_descriptorReuseMemo) {
            entry.valid = false;
        }
+        m_wireDescriptorRebind.valid = false;
        m_lastBindValid = false;
    }

@@ -716,6 +719,7 @@ namespace MobileGL::MG_Backend::DirectVulkan {
            for (auto& entry : m_descriptorReuseMemo) {
                entry.valid = false;
            }
+            m_wireDescriptorRebind.valid = false;
            MGLOG_D("UniformDescriptorBinder: freed %zu descriptor sets for destroyed layout", purgedSets);
        }
    }
@@ -1550,6 +1554,11 @@ namespace MobileGL::MG_Backend::DirectVulkan {
        if (frame.activeDescriptorPoolIndex >= frame.descriptorPools.size()) {
            frame.activeDescriptorPoolIndex = 0;
        }
+        if (TryRebindWireDescriptorSet(commandBuffer, program, programObj, frameIndex, bindPoint)) return true;
+        // What the full resolve below proves for the next draw's rebind (WireDescriptorRebind).
+        Bool rebindEligible = true;
+        auto& rebindResources = m_wireRebindResourcesScratch;
+        rebindResources.clear();

        // The descriptor set is chosen AFTER the writes are built (below), so a draw
        // whose resolved descriptor content matches the previous draw can reuse that
@@ -1609,6 +1618,10 @@ namespace MobileGL::MG_Backend::DirectVulkan {
                break; // ascending, so nothing past the cap can follow
            }
            const auto kind = programObj.bindingKinds[binding];
+            if (kind != ProgramFactory::DescriptorBindingKind::UniformBufferDynamic &&
+                kind != ProgramFactory::DescriptorBindingKind::StorageBuffer &&
+                kind != ProgramFactory::DescriptorBindingKind::CombinedImageSampler)
+                rebindEligible = false;

            VkWriteDescriptorSet write{};
            write.sType = VK_STRUCTURE_TYPE_WRITE_DESCRIPTOR_SET;
@@ -1729,8 +1742,12 @@ namespace MobileGL::MG_Backend::DirectVulkan {
                const SizeT firstImageInfoIndex = imageInfos.size();
                for (Uint32 element = 0; element < descriptorCount; ++element) {
                    VkDescriptorImageInfo imageInfo{};
+                    VkTextureManager::TextureResource* sampledResource = nullptr;
                    const Bool hasImage = ResolveWireImageDescriptor(commandBuffer, program, programObj, binding,
-                                                                     element, false, imageInfo);
+                                                                     element, false, imageInfo, &sampledResource);
+                    // A placeholder (an empty unit) has no resource to re-check: full resolve.
+                    if (sampledResource == nullptr) rebindEligible = false;
+                    else rebindResources.push_back(sampledResource);
                    if (!hasImage) {
                        MGLOG_E_ONCE(
                            "UniformDescriptorBinder::BindProgramUniformBuffers failed: sampler binding %u element %u "
@@ -1828,6 +1845,101 @@ namespace MobileGL::MG_Backend::DirectVulkan {

        BindDescriptorSetDeduped(commandBuffer, bindPoint, programObj.pipelineLayout, descriptorSet,
                                 dynamicOffsets);
+
+        // Stamp what this full resolve depended on, for TryRebindWireDescriptorSet. Taken after
+        // the walk: the walk's own syncs and barriers are part of what it proved.
+        auto& rebind = m_wireDescriptorRebind;
+        rebind.valid = rebindEligible && descriptorSet != VK_NULL_HANDLE &&
+                       WireImageWriteEpoch() == m_wireImageBarrierEpoch;
+        if (rebind.valid) {
+            const auto& st = MG_Pipe::MGPipeApplier();
+            rebind.frameIndex = frameIndex;
+            rebind.bindPoint = bindPoint;
+            rebind.programHash = programObj.hash;
+            rebind.layout = programObj.descriptorSetLayout;
+            rebind.pipelineLayout = programObj.pipelineLayout;
+            rebind.programHandle = program.Handle();
+            rebind.programSerial = program.GetBackendStateVersion();
+            rebind.programBindingsSerial = program.GetBlockBindingVersion();
+            rebind.contextSerial = st.ContextSerial;
+            rebind.samplerViewsSerial = st.SamplerViewsSerial;
+            rebind.samplerStatesSerial = st.SamplerStatesSerial;
+            rebind.shaderImagesSerial = st.ShaderImagesSerial;
+            rebind.shaderBuffersSerial = st.ShaderBuffersSerial;
+            rebind.textureShutterSerial = st.TextureShutterSerial;
+            rebind.storeDestroyEpoch = m_bufferManager->GetWireStoreDestroyEpoch();
+            rebind.textureImageEpoch = m_textureManager->GetTextureImageEpoch();
+            rebind.resourceEraseEpoch = m_textureManager->GetResourceEraseEpoch();
+            rebind.samplerDestroyEpoch = m_samplerManager->DestroyEpoch();
+            rebind.samplerFrameBoundary = m_samplerManager->FrameBoundaryCount();
+            rebind.set = descriptorSet;
+            rebind.sampledResources.assign(rebindResources.begin(), rebindResources.end());
+            rebind.bufferInfos.assign(bufferInfos.begin(), bufferInfos.end());
+        }
+        return true;
+    }
+
+    Bool UniformManager::TryRebindWireDescriptorSet(VkCommandBuffer commandBuffer, const MagmaProgramSource& program,
+                                                    const ProgramFactory::VkProgramObject& programObj,
+                                                    Uint32 frameIndex, VkPipelineBindPoint bindPoint) {
+        const auto& rebind = m_wireDescriptorRebind;
+        if (!rebind.valid || rebind.frameIndex != frameIndex || rebind.bindPoint != bindPoint ||
+            rebind.programHash != programObj.hash || rebind.layout != programObj.descriptorSetLayout ||
+            rebind.pipelineLayout != programObj.pipelineLayout || !(rebind.programHandle == program.Handle()) ||
+            rebind.programSerial != program.GetBackendStateVersion() ||
+            rebind.programBindingsSerial != program.GetBlockBindingVersion())
+            return false;
+        const auto& st = MG_Pipe::MGPipeApplier();
+        if (rebind.contextSerial != st.ContextSerial || rebind.samplerViewsSerial != st.SamplerViewsSerial ||
+            rebind.samplerStatesSerial != st.SamplerStatesSerial || rebind.shaderImagesSerial != st.ShaderImagesSerial ||
+            rebind.shaderBuffersSerial != st.ShaderBuffersSerial || rebind.textureShutterSerial != st.TextureShutterSerial)
+            return false;
+        if (rebind.storeDestroyEpoch != m_bufferManager->GetWireStoreDestroyEpoch() ||
+            rebind.textureImageEpoch != m_textureManager->GetTextureImageEpoch() ||
+            rebind.resourceEraseEpoch != m_textureManager->GetResourceEraseEpoch() ||
+            rebind.samplerDestroyEpoch != m_samplerManager->DestroyEpoch() ||
+            rebind.samplerFrameBoundary != m_samplerManager->FrameBoundaryCount() ||
+            WireImageWriteEpoch() != m_wireImageBarrierEpoch)
+            return false;
+        // The resource pointers are good while the erase epoch holds (checked above). A sampled
+        // image that left GENERAL (rendered to, copied into) needs the full resolve's transition.
+        for (const auto* resource : rebind.sampledResources)
+            if (resource->layout != VK_IMAGE_LAYOUT_GENERAL) return false;
+        // The buffer descriptors, in the walk's order, re-resolved: a UBO's dynamic offset is this
+        // draw's; its buffer and range, and every storage buffer's window, must be the set's.
+        auto& infos = m_wireRebindBufferScratch;
+        infos.clear();
+        auto& dynamicOffsets = m_dynamicOffsetsScratch;
+        dynamicOffsets.clear();
+        for (const Uint32 binding : programObj.activeBindings) {
+            if (binding >= m_maxBindings) break;
+            const auto kind = programObj.bindingKinds[binding];
+            const Uint32 count = BindingDescriptorCount(programObj, binding);
+            if (kind == ProgramFactory::DescriptorBindingKind::UniformBufferDynamic) {
+                for (Uint32 element = 0; element < count; ++element) {
+                    VkDescriptorBufferInfo info{};
+                    Uint32 offset = 0;
+                    if (!ResolveDynamicUboDescriptor(program, programObj, binding, element, frameIndex, info.buffer,
+                                                     info.range, offset))
+                        return false;
+                    infos.push_back(info);
+                    dynamicOffsets.push_back(offset);
+                }
+            } else if (kind == ProgramFactory::DescriptorBindingKind::StorageBuffer) {
+                for (Uint32 element = 0; element < count; ++element) {
+                    VkDescriptorBufferInfo info{};
+                    if (!ResolveStorageBufferDescriptor(program, programObj, binding, element, info)) return false;
+                    infos.push_back(info);
+                }
+            }
+        }
+        if (infos.size() != rebind.bufferInfos.size()) return false;
+        for (SizeT i = 0; i < infos.size(); ++i) {
+            const auto& a = infos[i];
+            const auto& b = rebind.bufferInfos[i];
+            if (a.buffer != b.buffer || a.offset != b.offset || a.range != b.range) return false;
+        }
+        BindDescriptorSetDeduped(commandBuffer, bindPoint, programObj.pipelineLayout, rebind.set, dynamicOffsets);
        return true;
    }
 } // namespace MobileGL::MG_Backend::DirectVulkan
@@ -260,7 +260,41 @@ namespace MobileGL::MG_Backend::DirectVulkan {
                                                   Bool storage);
        Bool ResolveWireImageDescriptor(VkCommandBuffer commandBuffer, const MagmaProgramSource& program,
                                       const ProgramFactory::VkProgramObject& programObj, Uint32 binding,
-                                       Uint32 element, Bool storage, VkDescriptorImageInfo& out) const;
+                                       Uint32 element, Bool storage, VkDescriptorImageInfo& out,
+                                       VkTextureManager::TextureResource** outResource = nullptr) const;
+        // P14: THE WIRE DESCRIPTOR REBIND. A draw whose image descriptors cannot have changed since
+        // the last full resolve of the same program in the same frame - same applier context, same
+        // unit / sampler / image / buffer-binding serials, same texture shutter, no texture image
+        // re-created or erased, no sampler destroyed, every sampled image still in GENERAL and no
+        // image write awaiting its barrier - re-resolves only its buffer descriptors (the UBO
+        // dynamic offsets move every draw) and, when those name the same buffers and ranges,
+        // rebinds the set it already has. Anything else, or any program with a texel buffer, storage
+        // image or placeholder descriptor, takes the full resolve.
+        struct WireDescriptorRebind {
+            Bool valid = false;
+            Uint32 frameIndex = 0;
+            VkPipelineBindPoint bindPoint = VK_PIPELINE_BIND_POINT_GRAPHICS;
+            Uint64 programHash = 0;
+            VkDescriptorSetLayout layout = VK_NULL_HANDLE;
+            VkPipelineLayout pipelineLayout = VK_NULL_HANDLE;
+            MG_Pipe::MGPipeHandle programHandle = MG_Pipe::kMGPipeNullHandle;
+            Uint64 programSerial = 0, programBindingsSerial = 0;
+            Uint64 contextSerial = 0, samplerViewsSerial = 0, samplerStatesSerial = 0, shaderImagesSerial = 0;
+            Uint64 shaderBuffersSerial = 0, textureShutterSerial = 0;
+            Uint64 storeDestroyEpoch = 0, textureImageEpoch = 0, resourceEraseEpoch = 0;
+            Uint64 samplerDestroyEpoch = 0, samplerFrameBoundary = 0;
+            VkDescriptorSet set = VK_NULL_HANDLE;
+            Vector<VkTextureManager::TextureResource*> sampledResources;
+            // The buffer descriptors in walk order: dynamic UBOs with offset 0 (their offset is the
+            // dynamic one), storage buffers whole.
+            Vector<VkDescriptorBufferInfo> bufferInfos;
+        };
+        WireDescriptorRebind m_wireDescriptorRebind;
+        Vector<VkDescriptorBufferInfo> m_wireRebindBufferScratch;
+        Vector<VkTextureManager::TextureResource*> m_wireRebindResourcesScratch;
+        Bool TryRebindWireDescriptorSet(VkCommandBuffer commandBuffer, const MagmaProgramSource& program,
+                                        const ProgramFactory::VkProgramObject& programObj, Uint32 frameIndex,
+                                        VkPipelineBindPoint bindPoint);
        Bool ResolveWireTexelBufferDescriptor(const MagmaProgramSource& program,
                                             const ProgramFactory::VkProgramObject& programObj, Uint32 binding,
                                             Uint32 frameIndex, Bool storage, VkBufferView& out);