Vulkan: Add workaround for nvidia to always merge barriers into one

include/platform/FeaturesVk.h

@@ -308,6 +308,15 @@ struct FeaturesVk : FeatureSetBase
     Feature supportDepthStencilRenderingFeedbackLoops = {
         "support_depth_stencil_rendering_feedback_loops", FeatureCategory::VulkanFeatures,
         "Suport depth/stencil rendering feedback loops", &members, "http://anglebug.com/4490"};
+
+    // Desktop (at least NVIDIA) drivers prefer combining barriers into one vkCmdPipelineBarrier
+    // call over issuing multiple barrier calls with fine grained dependency information to have
+    // better performance. http://anglebug.com/4633
+    Feature preferAggregateBarrierCalls = {
+        "prefer_aggregate_barrier_calls", FeatureCategory::VulkanWorkarounds,
+        "Single barrier call is preferred over multiple calls with "
+        "fine grained pipeline stage dependency information",
+        &members, "http://anglebug.com/4633"};
 };
 
 inline FeaturesVk::FeaturesVk()  = default;

src/libANGLE/renderer/vulkan/ContextVk.cpp

@@ -640,8 +640,9 @@ ContextVk::ContextVk(const gl::State &state, gl::ErrorSet *errorSet, RendererVk
       mEmulateSeamfulCubeMapSampling(false),
       mUseOldRewriteStructSamplers(false),
       mPoolAllocator(kDefaultPoolAllocatorPageSize, 1),
-      mOutsideRenderPassCommands(false),
-      mRenderPassCommands(true),
+      mOutsideRenderPassCommands(false,
+                                 renderer->getFeatures().preferAggregateBarrierCalls.enabled),
+      mRenderPassCommands(true, renderer->getFeatures().preferAggregateBarrierCalls.enabled),
       mHasPrimaryCommands(false),
       mGpuEventsEnabled(false),
       mGpuClockSync{std::numeric_limits<double>::max(), std::numeric_limits<double>::max()},

src/libANGLE/renderer/vulkan/RendererVk.cpp

@@ -1693,6 +1693,8 @@ void RendererVk::initFeatures(DisplayVk *displayVk, const ExtensionNameList &dev
 
     ANGLE_FEATURE_CONDITION(&mFeatures, supportDepthStencilRenderingFeedbackLoops, true);
 
+    ANGLE_FEATURE_CONDITION(&mFeatures, preferAggregateBarrierCalls, !IsAndroid());
+
     angle::PlatformMethods *platform = ANGLEPlatformCurrent();
     platform->overrideFeaturesVk(platform, &mFeatures);
 

src/libANGLE/renderer/vulkan/vk_helpers.cpp

@@ -511,7 +511,7 @@ VkImageLayout ConvertImageLayoutToVkImageLayout(ImageLayout imageLayout)
 }
 
 // CommandBufferHelper implementation.
-CommandBufferHelper::CommandBufferHelper(bool hasRenderPass)
+CommandBufferHelper::CommandBufferHelper(bool hasRenderPass, bool mergeBarriers)
     : mPipelineBarriers(),
       mPipelineBarrierMask(),
       mCounter(0),
@@ -520,7 +520,8 @@ CommandBufferHelper::CommandBufferHelper(bool hasRenderPass)
       mTransformFeedbackCounterBuffers{},
       mValidTransformFeedbackBufferCount(0),
       mRebindTransformFeedbackBuffers(false),
-      mIsRenderPassCommandBuffer(hasRenderPass)
+      mIsRenderPassCommandBuffer(hasRenderPass),
+      mMergeBarriers(mergeBarriers)
 {}
 
 CommandBufferHelper::~CommandBufferHelper()
@@ -591,15 +592,30 @@ void CommandBufferHelper::imageWrite(vk::ResourceUseList *resourceUseList,
 
 void CommandBufferHelper::executeBarriers(vk::PrimaryCommandBuffer *primary)
 {
-    if (!mPipelineBarrierMask.any())
+    // make a local copy for faster access
+    PipelineStagesMask mask = mPipelineBarrierMask;
+    if (mask.none())
     {
         return;
     }
 
-    for (PipelineStage pipelineStage : mPipelineBarrierMask)
+    if (mMergeBarriers)
     {
-        PipelineBarrier &barrier = mPipelineBarriers[pipelineStage];
-        barrier.writeCommand(primary);
+        PipelineStagesMask::Iterator iter = mask.begin();
+        PipelineBarrier &barrier          = mPipelineBarriers[*iter];
+        for (++iter; iter != mask.end(); ++iter)
+        {
+            barrier.merge(&mPipelineBarriers[*iter]);
+        }
+        barrier.execute(primary);
+    }
+    else
+    {
+        for (PipelineStage pipelineStage : mask)
+        {
+            PipelineBarrier &barrier = mPipelineBarriers[pipelineStage];
+            barrier.execute(primary);
+        }
     }
     mPipelineBarrierMask.reset();
 }

src/libANGLE/renderer/vulkan/vk_helpers.h

@@ -600,7 +600,7 @@ class PipelineBarrier : angle::NonCopyable
 
     bool isEmpty() const { return mImageMemoryBarriers.empty() && mMemoryBarrierSrcAccess == 0; }
 
-    void writeCommand(PrimaryCommandBuffer *primary)
+    void execute(PrimaryCommandBuffer *primary)
     {
         if (isEmpty())
         {
@@ -823,7 +823,7 @@ class BufferHelper final : public Resource
 struct CommandBufferHelper : angle::NonCopyable
 {
   public:
-    CommandBufferHelper(bool canHaveRenderPass);
+    CommandBufferHelper(bool canHaveRenderPass, bool mergeBarriers);
     ~CommandBufferHelper();
 
     // General Functions (non-renderPass specific)
@@ -950,6 +950,7 @@ struct CommandBufferHelper : angle::NonCopyable
     bool mRebindTransformFeedbackBuffers;
 
     const bool mIsRenderPassCommandBuffer;
+    const bool mMergeBarriers;
 };
 
 // Imagine an image going through a few layout transitions: