Add compute to D3D12 backend

src/backend/d3d12/BufferD3D12.cpp

@@ -25,6 +25,16 @@ namespace backend {
 namespace d3d12 {
 
     namespace {
+        D3D12_RESOURCE_FLAGS D3D12ResourceFlags(nxt::BufferUsageBit usage) {
+            D3D12_RESOURCE_FLAGS flags = D3D12_RESOURCE_FLAG_NONE;
+
+            if (usage & nxt::BufferUsageBit::Storage) {
+                flags |= D3D12_RESOURCE_FLAG_ALLOW_UNORDERED_ACCESS;
+            }
+
+            return flags;
+        }
+
         D3D12_RESOURCE_STATES D3D12BufferUsage(nxt::BufferUsageBit usage) {
             D3D12_RESOURCE_STATES resourceState = D3D12_RESOURCE_STATE_COMMON;
 
@@ -72,7 +82,7 @@ namespace d3d12 {
         resourceDescriptor.SampleDesc.Count = 1;
         resourceDescriptor.SampleDesc.Quality = 0;
         resourceDescriptor.Layout = D3D12_TEXTURE_LAYOUT_ROW_MAJOR;
-        resourceDescriptor.Flags = D3D12_RESOURCE_FLAG_NONE;
+        resourceDescriptor.Flags = D3D12ResourceFlags(GetAllowedUsage());
 
         auto heapType = D3D12HeapType(GetAllowedUsage());
         auto bufferUsage = D3D12BufferUsage(GetUsage());

src/backend/d3d12/CommandBufferD3D12.cpp

@@ -488,6 +488,9 @@ namespace d3d12 {
                         ComputePipeline* pipeline = ToBackend(cmd->pipeline).Get();
                         PipelineLayout* layout = ToBackend(pipeline->GetLayout());
 
+                        commandList->SetComputeRootSignature(layout->GetRootSignature().Get());
+                        commandList->SetPipelineState(pipeline->GetPipelineState().Get());
+
                         // TODO(enga@google.com): Implement compute pipelines
                         bindingTracker.SetInheritedBindGroups(commandList, lastLayout, layout);
                         lastLayout = layout;

src/backend/d3d12/ComputePipelineD3D12.cpp

@@ -48,7 +48,7 @@ namespace d3d12 {
             { nullptr },
             nullptr,
             entryPoint.c_str(),
-            "cs_5_0",
+            "cs_5_1",
             compileFlags,
             0,
             &compiledShader,