Add code path to use spvc in Metal backend

BUG=dawn:291

Change-Id: Idf20496bac733b14db3b7df7eb86ff0a23a9d826
Reviewed-on: https://dawn-review.googlesource.com/c/dawn/+/15161
Commit-Queue: Ryan Harrison <rharrison@chromium.org>
Reviewed-by: Kai Ninomiya <kainino@chromium.org>
Reviewed-by: Corentin Wallez <cwallez@chromium.org>

src/dawn_native/metal/ComputePipelineMTL.mm

@@ -32,7 +32,7 @@ namespace dawn_native { namespace metal {
     MaybeError ComputePipeline::Initialize(const ComputePipelineDescriptor* descriptor) {
         auto mtlDevice = ToBackend(GetDevice())->GetMTLDevice();
 
-        const ShaderModule* computeModule = ToBackend(descriptor->computeStage.module);
+        ShaderModule* computeModule = ToBackend(descriptor->computeStage.module);
         const char* computeEntryPoint = descriptor->computeStage.entryPoint;
         ShaderModule::MetalFunctionData computeData;
         DAWN_TRY(computeModule->GetFunction(computeEntryPoint, SingleShaderStage::Compute,

src/dawn_native/metal/RenderPipelineMTL.mm

@@ -330,7 +330,7 @@ namespace dawn_native { namespace metal {
 
         MTLRenderPipelineDescriptor* descriptorMTL = [MTLRenderPipelineDescriptor new];
 
-        const ShaderModule* vertexModule = ToBackend(descriptor->vertexStage.module);
+        ShaderModule* vertexModule = ToBackend(descriptor->vertexStage.module);
         const char* vertexEntryPoint = descriptor->vertexStage.entryPoint;
         ShaderModule::MetalFunctionData vertexData;
         DAWN_TRY(vertexModule->GetFunction(vertexEntryPoint, SingleShaderStage::Vertex,
@@ -341,7 +341,7 @@ namespace dawn_native { namespace metal {
             mStagesRequiringStorageBufferLength |= wgpu::ShaderStage::Vertex;
         }
 
-        const ShaderModule* fragmentModule = ToBackend(descriptor->fragmentStage->module);
+        ShaderModule* fragmentModule = ToBackend(descriptor->fragmentStage->module);
         const char* fragmentEntryPoint = descriptor->fragmentStage->entryPoint;
         ShaderModule::MetalFunctionData fragmentData;
         DAWN_TRY(fragmentModule->GetFunction(fragmentEntryPoint, SingleShaderStage::Fragment,

src/dawn_native/metal/ShaderModuleMTL.h

@@ -46,7 +46,7 @@ namespace dawn_native { namespace metal {
         MaybeError GetFunction(const char* functionName,
                                SingleShaderStage functionStage,
                                const PipelineLayout* layout,
-                               MetalFunctionData* out) const;
+                               MetalFunctionData* out);
 
       private:
         ShaderModule(Device* device, const ShaderModuleDescriptor* descriptor);

src/dawn_native/metal/ShaderModuleMTL.mm

@@ -39,6 +39,20 @@ namespace dawn_native { namespace metal {
             }
         }
 
+        shaderc_spvc_execution_model ToSpvcExecutionModel(SingleShaderStage stage) {
+            switch (stage) {
+                case SingleShaderStage::Vertex:
+                    return shaderc_spvc_execution_model_vertex;
+                case SingleShaderStage::Fragment:
+                    return shaderc_spvc_execution_model_fragment;
+                case SingleShaderStage::Compute:
+                    return shaderc_spvc_execution_model_glcompute;
+                default:
+                    UNREACHABLE();
+                    return shaderc_spvc_execution_model_invalid;
+            }
+        }
+
         shaderc_spvc::CompileOptions GetMSLCompileOptions() {
             // If these options are changed, the values in DawnSPIRVCrossGLSLFastFuzzer.cpp need to
             // be updated.
@@ -94,7 +108,7 @@ namespace dawn_native { namespace metal {
     MaybeError ShaderModule::GetFunction(const char* functionName,
                                          SingleShaderStage functionStage,
                                          const PipelineLayout* layout,
-                                         ShaderModule::MetalFunctionData* out) const {
+                                         ShaderModule::MetalFunctionData* out) {
         ASSERT(!IsError());
         ASSERT(out);
         std::unique_ptr<spirv_cross::CompilerMSL> compiler_impl;
@@ -137,30 +151,58 @@ namespace dawn_native { namespace metal {
             for (uint32_t binding : IterateBitSet(bgInfo.mask)) {
                 for (auto stage : IterateStages(bgInfo.visibilities[binding])) {
                     uint32_t index = layout->GetBindingIndexInfo(stage)[group][binding];
-
+                    if (GetDevice()->IsToggleEnabled(Toggle::UseSpvc)) {
+                        shaderc_spvc_msl_resource_binding mslBinding;
+                        mslBinding.stage = ToSpvcExecutionModel(stage);
+                        mslBinding.desc_set = group;
+                        mslBinding.binding = binding;
+                        mslBinding.msl_buffer = mslBinding.msl_texture = mslBinding.msl_sampler =
+                            index;
+                        DAWN_TRY(CheckSpvcSuccess(mSpvcContext.AddMSLResourceBinding(mslBinding),
+                                                  "Unable to add MSL Resource Binding"));
+                    } else {
                         spirv_cross::MSLResourceBinding mslBinding;
                         mslBinding.stage = SpirvExecutionModelForStage(stage);
                         mslBinding.desc_set = group;
                         mslBinding.binding = binding;
-                    mslBinding.msl_buffer = mslBinding.msl_texture = mslBinding.msl_sampler = index;
+                        mslBinding.msl_buffer = mslBinding.msl_texture = mslBinding.msl_sampler =
+                            index;
 
                         compiler->add_msl_resource_binding(mslBinding);
                     }
                 }
             }
+        }
 
         {
+            if (GetDevice()->IsToggleEnabled(Toggle::UseSpvc)) {
+                shaderc_spvc_execution_model executionModel = ToSpvcExecutionModel(functionStage);
+                shaderc_spvc_workgroup_size size;
+                DAWN_TRY(CheckSpvcSuccess(
+                    mSpvcContext.GetWorkgroupSize(functionName, executionModel, &size),
+                    "Unable to get workgroup size for shader"));
+                out->localWorkgroupSize = MTLSizeMake(size.x, size.y, size.z);
+            } else {
                 spv::ExecutionModel executionModel = SpirvExecutionModelForStage(functionStage);
                 auto size = compiler->get_entry_point(functionName, executionModel).workgroup_size;
                 out->localWorkgroupSize = MTLSizeMake(size.x, size.y, size.z);
             }
+        }
 
         {
             // SPIRV-Cross also supports re-ordering attributes but it seems to do the correct thing
             // by default.
-            std::string msl = compiler->compile();
+            NSString* mslSource;
-            NSString* mslSource = [NSString stringWithFormat:@"%s", msl.c_str()];
+            if (GetDevice()->IsToggleEnabled(Toggle::UseSpvc)) {
+                shaderc_spvc::CompilationResult result;
+                DAWN_TRY(CheckSpvcSuccess(mSpvcContext.CompileShader(&result),
+                                          "Unable to compile shader"));
 
+                mslSource = [NSString stringWithFormat:@"%s", result.GetStringOutput().c_str()];
+            } else {
+                std::string msl = compiler->compile();
+                mslSource = [NSString stringWithFormat:@"%s", msl.c_str()];
+            }
             auto mtlDevice = ToBackend(GetDevice())->GetMTLDevice();
             NSError* error = nil;
             id<MTLLibrary> library = [mtlDevice newLibraryWithSource:mslSource
@@ -187,7 +229,13 @@ namespace dawn_native { namespace metal {
             [library release];
         }
 
+        if (GetDevice()->IsToggleEnabled(Toggle::UseSpvc)) {
+            DAWN_TRY(
+                CheckSpvcSuccess(mSpvcContext.NeedsBufferSizeBuffer(&out->needsStorageBufferLength),
+                                 "Unable to determine if shader needs buffer size buffer"));
+        } else {
             out->needsStorageBufferLength = compiler->needs_buffer_size_buffer();
+        }
 
         return {};
     }