Vulkan: work around vkCmdCopyBuffer bug.

src/libANGLE/renderer/vulkan/FeaturesVk.h

@@ -33,7 +33,11 @@ struct FeaturesVk
     // -Point sprites tests
     // -texStorage
     bool flipViewportY = false;
+
+    // Add an extra copy region when using vkCmdCopyBuffer as the Windows Intel driver seems
+    // to have a bug where the last region is ignored.
+    bool extraCopyBufferRegion = false;
 };
 }  // namespace rx
 
-#endif  // LIBANGLE_RENDERER_VULKAN_FEATURESVK_H_
+#endif  // LIBANGLE_RENDERER_VULKAN_FEATURESVK_H_
\ No newline at end of file

src/libANGLE/renderer/vulkan/RendererVk.cpp

@@ -689,6 +689,11 @@ void RendererVk::initFeatures()
     // TODO(lucferron): Currently disabled on Intel only since many tests are failing and need
     // investigation. http://anglebug.com/2728
     mFeatures.flipViewportY = !IsIntel(mPhysicalDeviceProperties.vendorID);
+
+#ifdef ANGLE_PLATFORM_WINDOWS
+    // http://anglebug.com/2838
+    mFeatures.extraCopyBufferRegion = IsIntel(mPhysicalDeviceProperties.vendorID);
+#endif
 }
 
 void RendererVk::ensureCapsInitialized() const

src/libANGLE/renderer/vulkan/vk_helpers.cpp

@@ -429,7 +429,7 @@ angle::Result LineLoopHelper::getIndexBufferForElementArrayBuffer(ContextVk *con
     uint32_t *indices          = nullptr;
 
     auto unitSize = (indexType == VK_INDEX_TYPE_UINT16 ? sizeof(uint16_t) : sizeof(uint32_t));
-    size_t allocateBytes = unitSize * (indexCount + 1);
+    size_t allocateBytes = unitSize * (indexCount + 1) + 1;
 
     mDynamicIndexBuffer.releaseRetainedBuffers(context->getRenderer());
     ANGLE_TRY(mDynamicIndexBuffer.allocate(context, allocateBytes,
@@ -438,16 +438,19 @@ angle::Result LineLoopHelper::getIndexBufferForElementArrayBuffer(ContextVk *con
 
     VkDeviceSize sourceOffset = static_cast<VkDeviceSize>(elementArrayOffset);
     uint64_t unitCount        = static_cast<VkDeviceSize>(indexCount);
-    VkBufferCopy copy1        = {sourceOffset, *bufferOffsetOut, unitCount * unitSize};
-    VkBufferCopy copy2        = {sourceOffset, *bufferOffsetOut + unitCount * unitSize, unitSize};
-    std::array<VkBufferCopy, 2> copies = {{copy1, copy2}};
+    angle::FixedVector<VkBufferCopy, 3> copies = {
+        {sourceOffset, *bufferOffsetOut, unitCount * unitSize},
+        {sourceOffset, *bufferOffsetOut + unitCount * unitSize, unitSize},
+    };
+    if (context->getRenderer()->getFeatures().extraCopyBufferRegion)
+        copies.push_back({sourceOffset, *bufferOffsetOut + (unitCount + 1) * unitSize, 1});
 
     vk::CommandBuffer *commandBuffer;
     ANGLE_TRY(recordCommands(context, &commandBuffer));
 
     elementArrayBufferVk->addReadDependency(this);
-    commandBuffer->copyBuffer(elementArrayBufferVk->getVkBuffer().getHandle(), *bufferHandleOut, 2,
-                              copies.data());
+    commandBuffer->copyBuffer(elementArrayBufferVk->getVkBuffer().getHandle(), *bufferHandleOut,
+                              copies.size(), copies.data());
 
     ANGLE_TRY(mDynamicIndexBuffer.flush(context));
     return angle::Result::Continue();

src/tests/gl_tests/LineLoopTest.cpp

@@ -149,10 +149,6 @@ TEST_P(LineLoopTest, LineLoopUByteIndexBuffer)
 
 TEST_P(LineLoopTest, LineLoopUShortIndexBuffer)
 {
-    // TODO(fjhenigman): Probabe driver bug. Work around it and/or notify vendor.
-    // http://anglebug.com/2838
-    ANGLE_SKIP_TEST_IF(IsVulkan() && IsWindows() && IsIntel());
-
     // Disable D3D11 SDK Layers warnings checks, see ANGLE issue 667 for details
     ignoreD3D11SDKLayersWarnings();