Factor computation of inherited bindgroups in PipelineLayoutBase

src/backend/Builder.cpp

@@ -17,6 +17,8 @@
 #include "backend/Device.h"
 #include "common/Assert.h"
 
+#include <iostream>
+
 namespace backend {
 
     bool BuilderBase::CanBeUsed() const {
@@ -76,6 +78,8 @@ namespace backend {
                 result->Release();
                 result = nullptr;
             }
+
+            if (!callback) std::cout << storedMessage << std::endl;
         } else {
             ASSERT(storedStatus == nxt::BuilderErrorStatus::Success);
             ASSERT(storedMessage.empty());

src/backend/CommandBufferStateTracker.cpp

@@ -520,23 +520,16 @@ namespace backend {
         return true;
     }
 
-
     bool CommandBufferStateTracker::SetPipelineCommon(PipelineBase* pipeline) {
         PipelineLayoutBase* layout = pipeline->GetLayout();
 
         aspects.reset(VALIDATION_ASPECT_BIND_GROUPS);
+        // Reset bindgroups but mark unused bindgroups as valid
         bindgroupsSet = ~layout->GetBindGroupsLayoutMask();
 
         // Only bindgroups that were not the same layout in the last pipeline need to be set again.
         if (lastPipeline) {
-            PipelineLayoutBase* lastLayout = lastPipeline->GetLayout();
+            bindgroupsSet |= layout->InheritedGroupsMask(lastPipeline->GetLayout());
-            for (uint32_t i = 0; i < kMaxBindGroups; ++i) {
-                if (lastLayout->GetBindGroupLayout(i) == layout->GetBindGroupLayout(i)) {
-                    bindgroupsSet |= uint64_t(1) << i;
-                } else {
-                    break;
-                }
-            }
         }
 
         lastPipeline = pipeline;

src/backend/PipelineLayout.cpp

@@ -35,6 +35,19 @@ namespace backend {
         return mask;
     }
 
+    std::bitset<kMaxBindGroups> PipelineLayoutBase::InheritedGroupsMask(const PipelineLayoutBase* other) const {
+        return { GroupsInheritUpTo(other) - 1 };
+    }
+
+    uint32_t PipelineLayoutBase::GroupsInheritUpTo(const PipelineLayoutBase* other) const {
+        for (uint32_t i = 0; i < kMaxBindGroups; ++i) {
+            if (!mask[i] || bindGroupLayouts[i].Get() != other->bindGroupLayouts[i].Get()) {
+                return i;
+            }
+        }
+        return kMaxBindGroups + 1;
+    }
+
     // PipelineLayoutBuilder
 
     PipelineLayoutBuilder::PipelineLayoutBuilder(DeviceBase* device) : Builder(device) {

src/backend/PipelineLayout.h

@@ -36,6 +36,13 @@ namespace backend {
             const BindGroupLayoutBase* GetBindGroupLayout(size_t group) const;
             const std::bitset<kMaxBindGroups> GetBindGroupsLayoutMask() const;
 
+            // Utility functions to compute inherited bind groups.
+            // Returns the inherited bind groups as a mask
+            std::bitset<kMaxBindGroups> InheritedGroupsMask(const PipelineLayoutBase* other) const;
+
+            // Returns the index of the first incompatible bind group (in the range [1, kMaxBindGroups + 1])
+            uint32_t GroupsInheritUpTo(const PipelineLayoutBase* other) const;
+
         protected:
             BindGroupLayoutArray bindGroupLayouts;
             std::bitset<kMaxBindGroups> mask;

src/backend/d3d12/CommandBufferD3D12.cpp

@@ -81,18 +81,9 @@ namespace d3d12 {
                     return;
                 }
 
-                auto mask = newLayout->GetBindGroupsLayoutMask();
+                uint32_t inheritUntil = oldLayout->GroupsInheritUpTo(newLayout);
-                for (uint32_t i = 0; i < kMaxBindGroups; ++i) {
+                for (uint32_t i = 0; i < inheritUntil; ++i) {
-                    // matching bind groups are inherited until they differ
+                    TrackSetBindGroup(bindGroups[i], i);
-                    if (mask[i] && oldLayout->GetBindGroupLayout(i) == newLayout->GetBindGroupLayout(i)) {
-                        BindGroup* group = bindGroups[i];
-                        if (group != nullptr) {
-                            TrackSetBindGroup(group, i);
-                        }
-                    }
-                    else {
-                        break;
-                    }
                 }
             }
 
@@ -130,18 +121,10 @@ namespace d3d12 {
                 if (oldLayout == nullptr) {
                     return;
                 }
-                auto mask = newLayout->GetBindGroupsLayoutMask();
+
-                for (uint32_t i = 0; i < kMaxBindGroups; ++i) {
+                uint32_t inheritUntil = oldLayout->GroupsInheritUpTo(newLayout);
-                    // matching bind groups are inherited until they differ
+                for (uint32_t i = 0; i < inheritUntil; ++i) {
-                    if (mask[i] && oldLayout->GetBindGroupLayout(i) == oldLayout->GetBindGroupLayout(i)) {
+                    SetBindGroup(commandList, newLayout, bindGroups[i], i, true);
-                        BindGroup* group = bindGroups[i];
-                        if (group != nullptr) {
-                            SetBindGroup(commandList, newLayout, group, i, true);
-                        }
-                    }
-                    else {
-                        break;
-                    }
                 }
             }