Vulkan: Enable nonzero_clear_resources_on_creation_for_testing on buffer

This patch enables nonzero_clear_resources_on_creation_for_testing
toggle on buffer on Vulkan backends as a preparation of supporting
buffer lazy-initialization in Dawn.

BUG=dawn:414
TEST=dawn_end2end_tests

Change-Id: I7619d02ae898e30fd15438d35437802a09e959cc
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/22981
Reviewed-by: Corentin Wallez <cwallez@chromium.org>
Reviewed-by: Kai Ninomiya <kainino@chromium.org>
Commit-Queue: Kai Ninomiya <kainino@chromium.org>

src/dawn_native/vulkan/BufferVk.cpp

@@ -165,6 +165,10 @@ namespace dawn_native { namespace vulkan {
                                         mMemoryAllocation.GetOffset()),
             "vkBindBufferMemory"));
 
+        if (device->IsToggleEnabled(Toggle::NonzeroClearResourcesOnCreationForTesting)) {
+            ClearBuffer(device->GetPendingRecordingContext(), ClearValue::NonZero);
+        }
+
         return {};
     }
 
@@ -283,4 +287,20 @@ namespace dawn_native { namespace vulkan {
         }
     }
 
+    void Buffer::ClearBuffer(CommandRecordingContext* recordingContext, ClearValue clearValue) {
+        ASSERT(recordingContext != nullptr);
+
+        // TODO(jiawei.shao@intel.com): support buffer lazy-initialization to 0.
+        ASSERT(clearValue == BufferBase::ClearValue::NonZero);
+
+        constexpr uint32_t kClearBufferValue = 0x01010101;
+
+        TransitionUsageNow(recordingContext, wgpu::BufferUsage::CopyDst);
+
+        Device* device = ToBackend(GetDevice());
+        // TODO(jiawei.shao@intel.com): find out why VK_WHOLE_SIZE doesn't work on old Windows Intel
+        // Vulkan drivers.
+        device->fn.CmdFillBuffer(recordingContext->commandBuffer, mHandle, 0, GetSize(),
+                                 kClearBufferValue);
+    }
 }}  // namespace dawn_native::vulkan

src/dawn_native/vulkan/BufferVk.h

@@ -49,6 +49,7 @@ namespace dawn_native { namespace vulkan {
         ~Buffer() override;
         using BufferBase::BufferBase;
         MaybeError Initialize();
+        void ClearBuffer(CommandRecordingContext* recordingContext, ClearValue clearValue);
 
         // Dawn API
         MaybeError MapReadAsyncImpl(uint32_t serial) override;

src/tests/end2end/NonzeroBufferCreationTests.cpp

@@ -51,4 +51,5 @@ TEST_P(NonzeroBufferCreationTests, BufferCreationWithoutCopyDstUsage) {
 }
 
 DAWN_INSTANTIATE_TEST(NonzeroBufferCreationTests,
-                      MetalBackend({"nonzero_clear_resources_on_creation_for_testing"}));
+                      MetalBackend({"nonzero_clear_resources_on_creation_for_testing"}),
+                      VulkanBackend({"nonzero_clear_resources_on_creation_for_testing"}));