src/dawn_native/metal/ShaderModuleMTL.mm - dawn - Git at Google

 // Copyright 2017 The Dawn Authors
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
 // You may obtain a copy of the License at
 //
 //     http://www.apache.org/licenses/LICENSE-2.0
 //
 // Unless required by applicable law or agreed to in writing, software
 // distributed under the License is distributed on an "AS IS" BASIS,
 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 // See the License for the specific language governing permissions and
 // limitations under the License.

 #include "dawn_native/metal/ShaderModuleMTL.h"

 #include "dawn_native/BindGroupLayout.h"
 #include "dawn_native/SpirvUtils.h"
 #include "dawn_native/TintUtils.h"
 #include "dawn_native/metal/DeviceMTL.h"
 #include "dawn_native/metal/PipelineLayoutMTL.h"
 #include "dawn_native/metal/RenderPipelineMTL.h"

 #include <spirv_msl.hpp>

 // Tint include must be after spirv_msl.hpp, because spirv-cross has its own
 // version of spirv_headers. We also need to undef SPV_REVISION because SPIRV-Cross
 // is at 3 while spirv-headers is at 4.
 #undef SPV_REVISION
 #include <tint/tint.h>

 #include <sstream>

 namespace dawn_native { namespace metal {

     // static
     ResultOrError<Ref<ShaderModule>> ShaderModule::Create(Device* device,
                                                           const ShaderModuleDescriptor* descriptor,
                                                           ShaderModuleParseResult* parseResult) {
         Ref<ShaderModule> module = AcquireRef(new ShaderModule(device, descriptor));
         DAWN_TRY(module->Initialize(parseResult));
         return module;
     }

     ShaderModule::ShaderModule(Device* device, const ShaderModuleDescriptor* descriptor)
         : ShaderModuleBase(device, descriptor) {
     }

     MaybeError ShaderModule::Initialize(ShaderModuleParseResult* parseResult) {
         ScopedTintICEHandler scopedICEHandler(GetDevice());
         return InitializeBase(parseResult);
     }

     ResultOrError<std::string> ShaderModule::TranslateToMSLWithTint(
         const char* entryPointName,
         SingleShaderStage stage,
         const PipelineLayout* layout,
         uint32_t sampleMask,
         const RenderPipeline* renderPipeline,
         const VertexState* vertexState,
         std::string* remappedEntryPointName,
         bool* needsStorageBufferLength) {
         ScopedTintICEHandler scopedICEHandler(GetDevice());

         std::ostringstream errorStream;
         errorStream << "Tint MSL failure:" << std::endl;

         // Remap BindingNumber to BindingIndex in WGSL shader
         using BindingRemapper = tint::transform::BindingRemapper;
         using BindingPoint = tint::transform::BindingPoint;
         BindingRemapper::BindingPoints bindingPoints;
         BindingRemapper::AccessControls accessControls;

         for (BindGroupIndex group : IterateBitSet(layout->GetBindGroupLayoutsMask())) {
             const BindGroupLayoutBase::BindingMap& bindingMap =
                 layout->GetBindGroupLayout(group)->GetBindingMap();
             for (const auto& it : bindingMap) {
                 BindingNumber bindingNumber = it.first;
                 BindingIndex bindingIndex = it.second;

                 const BindingInfo& bindingInfo =
                     layout->GetBindGroupLayout(group)->GetBindingInfo(bindingIndex);

                 if (!(bindingInfo.visibility & StageBit(stage))) {
                     continue;
                 }

                 uint32_t shaderIndex = layout->GetBindingIndexInfo(stage)[group][bindingIndex];

                 BindingPoint srcBindingPoint{static_cast<uint32_t>(group),
                                              static_cast<uint32_t>(bindingNumber)};
                 BindingPoint dstBindingPoint{0, shaderIndex};
                 if (srcBindingPoint != dstBindingPoint) {
                     bindingPoints.emplace(srcBindingPoint, dstBindingPoint);
                 }
             }
         }

         tint::transform::Manager transformManager;
         tint::transform::DataMap transformInputs;

         if (stage == SingleShaderStage::Vertex &&
             GetDevice()->IsToggleEnabled(Toggle::MetalEnableVertexPulling)) {
             transformManager.Add<tint::transform::VertexPulling>();
             AddVertexPullingTransformConfig(*vertexState, entryPointName, kPullingBufferBindingSet,
                                             &transformInputs);

             for (VertexBufferSlot slot :
                  IterateBitSet(renderPipeline->GetVertexBufferSlotsUsed())) {
                 uint32_t metalIndex = renderPipeline->GetMtlVertexBufferIndex(slot);

                 // Tell Tint to map (kPullingBufferBindingSet, slot) to this MSL buffer index.
                 BindingPoint srcBindingPoint{static_cast<uint32_t>(kPullingBufferBindingSet),
                                              static_cast<uint8_t>(slot)};
                 BindingPoint dstBindingPoint{0, metalIndex};
                 if (srcBindingPoint != dstBindingPoint) {
                     bindingPoints.emplace(srcBindingPoint, dstBindingPoint);
                 }
             }
         }
         if (GetDevice()->IsRobustnessEnabled()) {
             transformManager.Add<tint::transform::BoundArrayAccessors>();
         }
         transformManager.Add<tint::transform::BindingRemapper>();
         transformManager.Add<tint::transform::Renamer>();
         transformManager.Add<tint::transform::Msl>();

         transformInputs.Add<BindingRemapper::Remappings>(std::move(bindingPoints),
                                                          std::move(accessControls),
                                                          /* mayCollide */ true);

         transformInputs.Add<tint::transform::Msl::Config>(kBufferLengthBufferSlot, sampleMask);

         tint::Program program;
         tint::transform::DataMap transformOutputs;
         DAWN_TRY_ASSIGN(program, RunTransforms(&transformManager, GetTintProgram(), transformInputs,
                                                &transformOutputs, nullptr));

         if (auto* data = transformOutputs.Get<tint::transform::Renamer::Data>()) {
             auto it = data->remappings.find(entryPointName);
             if (it == data->remappings.end()) {
                 return DAWN_VALIDATION_ERROR("Could not find remapped name for entry point.");
             }
             *remappedEntryPointName = it->second;
         } else {
             return DAWN_VALIDATION_ERROR("Transform output missing renamer data.");
         }

         if (auto* data = transformOutputs.Get<tint::transform::Msl::Result>()) {
             *needsStorageBufferLength = data->needs_storage_buffer_sizes;
         } else {
             return DAWN_VALIDATION_ERROR("Transform output missing MSL data.");
         }

         tint::writer::msl::Generator generator(&program);
         if (!generator.Generate()) {
             errorStream << "Generator: " << generator.error() << std::endl;
             return DAWN_VALIDATION_ERROR(errorStream.str().c_str());
         }

         std::string msl = generator.result();
         return std::move(msl);
     }

     ResultOrError<std::string> ShaderModule::TranslateToMSLWithSPIRVCross(
         const char* entryPointName,
         SingleShaderStage stage,
         const PipelineLayout* layout,
         uint32_t sampleMask,
         const RenderPipeline* renderPipeline,
         const VertexState* vertexState,
         std::string* remappedEntryPointName,
         bool* needsStorageBufferLength) {
         const std::vector<uint32_t>* spirv = &GetSpirv();
         spv::ExecutionModel executionModel = ShaderStageToExecutionModel(stage);

         std::vector<uint32_t> pullingSpirv;
         if (GetDevice()->IsToggleEnabled(Toggle::MetalEnableVertexPulling) &&
             stage == SingleShaderStage::Vertex) {
             if (GetDevice()->IsToggleEnabled(Toggle::UseTintGenerator)) {
                 DAWN_TRY_ASSIGN(pullingSpirv,
                                 GeneratePullingSpirv(GetTintProgram(), *vertexState, entryPointName,
                                                      kPullingBufferBindingSet));
             } else {
                 DAWN_TRY_ASSIGN(pullingSpirv,
                                 GeneratePullingSpirv(GetSpirv(), *vertexState, entryPointName,
                                                      kPullingBufferBindingSet));
             }
             spirv = &pullingSpirv;
         }

         // If these options are changed, the values in DawnSPIRVCrossMSLFastFuzzer.cpp need to
         // be updated.
         spirv_cross::CompilerMSL::Options options_msl;

         // Disable PointSize builtin for https://bugs.chromium.org/p/dawn/issues/detail?id=146
         // Because Metal will reject PointSize builtin if the shader is compiled into a render
         // pipeline that uses a non-point topology.
         // TODO (hao.x.li@intel.com): Remove this once WebGPU requires there is no
         // gl_PointSize builtin (https://github.com/gpuweb/gpuweb/issues/332).
         options_msl.enable_point_size_builtin = false;

         // Always use vertex buffer 30 (the last one in the vertex buffer table) to contain
         // the shader storage buffer lengths.
         options_msl.buffer_size_buffer_index = kBufferLengthBufferSlot;

         options_msl.additional_fixed_sample_mask = sampleMask;

         spirv_cross::CompilerMSL compiler(*spirv);
         compiler.set_msl_options(options_msl);
         compiler.set_entry_point(entryPointName, executionModel);

         // By default SPIRV-Cross will give MSL resources indices in increasing order.
         // To make the MSL indices match the indices chosen in the PipelineLayout, we build
         // a table of MSLResourceBinding to give to SPIRV-Cross.

         // Create one resource binding entry per stage per binding.
         for (BindGroupIndex group : IterateBitSet(layout->GetBindGroupLayoutsMask())) {
             const BindGroupLayoutBase::BindingMap& bindingMap =
                 layout->GetBindGroupLayout(group)->GetBindingMap();

             for (const auto& it : bindingMap) {
                 BindingNumber bindingNumber = it.first;
                 BindingIndex bindingIndex = it.second;

                 const BindingInfo& bindingInfo =
                     layout->GetBindGroupLayout(group)->GetBindingInfo(bindingIndex);

                 if (!(bindingInfo.visibility & StageBit(stage))) {
                     continue;
                 }

                 uint32_t shaderIndex = layout->GetBindingIndexInfo(stage)[group][bindingIndex];

                 spirv_cross::MSLResourceBinding mslBinding;
                 mslBinding.stage = executionModel;
                 mslBinding.desc_set = static_cast<uint32_t>(group);
                 mslBinding.binding = static_cast<uint32_t>(bindingNumber);
                 mslBinding.msl_buffer = mslBinding.msl_texture = mslBinding.msl_sampler =
                     shaderIndex;

                 compiler.add_msl_resource_binding(mslBinding);
             }
         }

         // Add vertex buffers bound as storage buffers
         if (GetDevice()->IsToggleEnabled(Toggle::MetalEnableVertexPulling) &&
             stage == SingleShaderStage::Vertex) {
             for (VertexBufferSlot slot :
                  IterateBitSet(renderPipeline->GetVertexBufferSlotsUsed())) {
                 uint32_t metalIndex = renderPipeline->GetMtlVertexBufferIndex(slot);

                 spirv_cross::MSLResourceBinding mslBinding;

                 mslBinding.stage = spv::ExecutionModelVertex;
                 mslBinding.desc_set = static_cast<uint32_t>(kPullingBufferBindingSet);
                 mslBinding.binding = static_cast<uint8_t>(slot);
                 mslBinding.msl_buffer = metalIndex;
                 compiler.add_msl_resource_binding(mslBinding);
             }
         }

         // SPIRV-Cross also supports re-ordering attributes but it seems to do the correct thing
         // by default.
         std::string msl = compiler.compile();

         // Some entry point names are forbidden in MSL so SPIRV-Cross modifies them. Query the
         // modified entryPointName from it.
         *remappedEntryPointName = compiler.get_entry_point(entryPointName, executionModel).name;
         *needsStorageBufferLength = compiler.needs_buffer_size_buffer();

         return std::move(msl);
     }

     MaybeError ShaderModule::CreateFunction(const char* entryPointName,
                                             SingleShaderStage stage,
                                             const PipelineLayout* layout,
                                             ShaderModule::MetalFunctionData* out,
                                             uint32_t sampleMask,
                                             const RenderPipeline* renderPipeline,
                                             const VertexState* vertexState) {
         ASSERT(!IsError());
         ASSERT(out);

         // Vertex stages must specify a renderPipeline and vertexState
         if (stage == SingleShaderStage::Vertex) {
             ASSERT(renderPipeline != nullptr);
             ASSERT(vertexState != nullptr);
         }

         std::string remappedEntryPointName;
         std::string msl;
         if (GetDevice()->IsToggleEnabled(Toggle::UseTintGenerator)) {
             DAWN_TRY_ASSIGN(
                 msl, TranslateToMSLWithTint(entryPointName, stage, layout, sampleMask,
                                             renderPipeline, vertexState, &remappedEntryPointName,
                                             &out->needsStorageBufferLength));
         } else {
             DAWN_TRY_ASSIGN(msl, TranslateToMSLWithSPIRVCross(entryPointName, stage, layout,
                                                               sampleMask, renderPipeline,
                                                               vertexState, &remappedEntryPointName,
                                                               &out->needsStorageBufferLength));
         }

         // Metal uses Clang to compile the shader as C++14. Disable everything in the -Wall
         // category. -Wunused-variable in particular comes up a lot in generated code, and some
         // (old?) Metal drivers accidentally treat it as a MTLLibraryErrorCompileError instead
         // of a warning.
         msl = R"(\
 #ifdef __clang__
 #pragma clang diagnostic ignored "-Wall"
 #endif
 )" + msl;

         NSRef<NSString> mslSource = AcquireNSRef([[NSString alloc] initWithUTF8String:msl.c_str()]);

         auto mtlDevice = ToBackend(GetDevice())->GetMTLDevice();
         NSError* error = nullptr;
         NSPRef<id<MTLLibrary>> library =
             AcquireNSPRef([mtlDevice newLibraryWithSource:mslSource.Get()
                                                   options:nullptr
                                                     error:&error]);
         if (error != nullptr) {
             if (error.code != MTLLibraryErrorCompileWarning) {
                 const char* errorString = [error.localizedDescription UTF8String];
                 return DAWN_VALIDATION_ERROR(std::string("Unable to create library object: ") +
                                              errorString);
             }
         }

         NSRef<NSString> name =
             AcquireNSRef([[NSString alloc] initWithUTF8String:remappedEntryPointName.c_str()]);
         out->function = AcquireNSPRef([*library newFunctionWithName:name.Get()]);

         if (GetDevice()->IsToggleEnabled(Toggle::MetalEnableVertexPulling) &&
             GetEntryPoint(entryPointName).usedVertexAttributes.any()) {
             out->needsStorageBufferLength = true;
         }

         return {};
     }
 }}  // namespace dawn_native::metal
	// Copyright 2017 The Dawn Authors
	//
	// Licensed under the Apache License, Version 2.0 (the "License");
	// you may not use this file except in compliance with the License.
	// You may obtain a copy of the License at
	//
	// http://www.apache.org/licenses/LICENSE-2.0
	//
	// Unless required by applicable law or agreed to in writing, software
	// distributed under the License is distributed on an "AS IS" BASIS,
	// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	// See the License for the specific language governing permissions and
	// limitations under the License.

	#include "dawn_native/metal/ShaderModuleMTL.h"

	#include "dawn_native/BindGroupLayout.h"
	#include "dawn_native/SpirvUtils.h"
	#include "dawn_native/TintUtils.h"
	#include "dawn_native/metal/DeviceMTL.h"
	#include "dawn_native/metal/PipelineLayoutMTL.h"
	#include "dawn_native/metal/RenderPipelineMTL.h"

	#include <spirv_msl.hpp>

	// Tint include must be after spirv_msl.hpp, because spirv-cross has its own
	// version of spirv_headers. We also need to undef SPV_REVISION because SPIRV-Cross
	// is at 3 while spirv-headers is at 4.
	#undef SPV_REVISION
	#include <tint/tint.h>

	#include <sstream>

	namespace dawn_native { namespace metal {

	// static
	ResultOrError<Ref<ShaderModule>> ShaderModule::Create(Device* device,
	const ShaderModuleDescriptor* descriptor,
	ShaderModuleParseResult* parseResult) {
	Ref<ShaderModule> module = AcquireRef(new ShaderModule(device, descriptor));
	DAWN_TRY(module->Initialize(parseResult));
	return module;
	}

	ShaderModule::ShaderModule(Device* device, const ShaderModuleDescriptor* descriptor)
	: ShaderModuleBase(device, descriptor) {
	}

	MaybeError ShaderModule::Initialize(ShaderModuleParseResult* parseResult) {
	ScopedTintICEHandler scopedICEHandler(GetDevice());
	return InitializeBase(parseResult);
	}

	ResultOrError<std::string> ShaderModule::TranslateToMSLWithTint(
	const char* entryPointName,
	SingleShaderStage stage,
	const PipelineLayout* layout,
	uint32_t sampleMask,
	const RenderPipeline* renderPipeline,
	const VertexState* vertexState,
	std::string* remappedEntryPointName,
	bool* needsStorageBufferLength) {
	ScopedTintICEHandler scopedICEHandler(GetDevice());

	std::ostringstream errorStream;
	errorStream << "Tint MSL failure:" << std::endl;

	// Remap BindingNumber to BindingIndex in WGSL shader
	using BindingRemapper = tint::transform::BindingRemapper;
	using BindingPoint = tint::transform::BindingPoint;
	BindingRemapper::BindingPoints bindingPoints;
	BindingRemapper::AccessControls accessControls;

	for (BindGroupIndex group : IterateBitSet(layout->GetBindGroupLayoutsMask())) {
	const BindGroupLayoutBase::BindingMap& bindingMap =
	layout->GetBindGroupLayout(group)->GetBindingMap();
	for (const auto& it : bindingMap) {
	BindingNumber bindingNumber = it.first;
	BindingIndex bindingIndex = it.second;

	const BindingInfo& bindingInfo =
	layout->GetBindGroupLayout(group)->GetBindingInfo(bindingIndex);

	if (!(bindingInfo.visibility & StageBit(stage))) {
	continue;
	}

	uint32_t shaderIndex = layout->GetBindingIndexInfo(stage)[group][bindingIndex];

	BindingPoint srcBindingPoint{static_cast<uint32_t>(group),
	static_cast<uint32_t>(bindingNumber)};
	BindingPoint dstBindingPoint{0, shaderIndex};
	if (srcBindingPoint != dstBindingPoint) {
	bindingPoints.emplace(srcBindingPoint, dstBindingPoint);
	}
	}
	}

	tint::transform::Manager transformManager;
	tint::transform::DataMap transformInputs;

	if (stage == SingleShaderStage::Vertex &&
	GetDevice()->IsToggleEnabled(Toggle::MetalEnableVertexPulling)) {
	transformManager.Add<tint::transform::VertexPulling>();
	AddVertexPullingTransformConfig(*vertexState, entryPointName, kPullingBufferBindingSet,
	&transformInputs);

	for (VertexBufferSlot slot :
	IterateBitSet(renderPipeline->GetVertexBufferSlotsUsed())) {
	uint32_t metalIndex = renderPipeline->GetMtlVertexBufferIndex(slot);

	// Tell Tint to map (kPullingBufferBindingSet, slot) to this MSL buffer index.
	BindingPoint srcBindingPoint{static_cast<uint32_t>(kPullingBufferBindingSet),
	static_cast<uint8_t>(slot)};
	BindingPoint dstBindingPoint{0, metalIndex};
	if (srcBindingPoint != dstBindingPoint) {
	bindingPoints.emplace(srcBindingPoint, dstBindingPoint);
	}
	}
	}
	if (GetDevice()->IsRobustnessEnabled()) {
	transformManager.Add<tint::transform::BoundArrayAccessors>();
	}
	transformManager.Add<tint::transform::BindingRemapper>();
	transformManager.Add<tint::transform::Renamer>();
	transformManager.Add<tint::transform::Msl>();

	transformInputs.Add<BindingRemapper::Remappings>(std::move(bindingPoints),
	std::move(accessControls),
	/* mayCollide */ true);

	transformInputs.Add<tint::transform::Msl::Config>(kBufferLengthBufferSlot, sampleMask);

	tint::Program program;
	tint::transform::DataMap transformOutputs;
	DAWN_TRY_ASSIGN(program, RunTransforms(&transformManager, GetTintProgram(), transformInputs,
	&transformOutputs, nullptr));

	if (auto* data = transformOutputs.Get<tint::transform::Renamer::Data>()) {
	auto it = data->remappings.find(entryPointName);
	if (it == data->remappings.end()) {
	return DAWN_VALIDATION_ERROR("Could not find remapped name for entry point.");
	}
	*remappedEntryPointName = it->second;
	} else {
	return DAWN_VALIDATION_ERROR("Transform output missing renamer data.");
	}

	if (auto* data = transformOutputs.Get<tint::transform::Msl::Result>()) {
	*needsStorageBufferLength = data->needs_storage_buffer_sizes;
	} else {
	return DAWN_VALIDATION_ERROR("Transform output missing MSL data.");
	}

	tint::writer::msl::Generator generator(&program);
	if (!generator.Generate()) {
	errorStream << "Generator: " << generator.error() << std::endl;
	return DAWN_VALIDATION_ERROR(errorStream.str().c_str());
	}

	std::string msl = generator.result();
	return std::move(msl);
	}

	ResultOrError<std::string> ShaderModule::TranslateToMSLWithSPIRVCross(
	const char* entryPointName,
	SingleShaderStage stage,
	const PipelineLayout* layout,
	uint32_t sampleMask,
	const RenderPipeline* renderPipeline,
	const VertexState* vertexState,
	std::string* remappedEntryPointName,
	bool* needsStorageBufferLength) {
	const std::vector<uint32_t>* spirv = &GetSpirv();
	spv::ExecutionModel executionModel = ShaderStageToExecutionModel(stage);

	std::vector<uint32_t> pullingSpirv;
	if (GetDevice()->IsToggleEnabled(Toggle::MetalEnableVertexPulling) &&
	stage == SingleShaderStage::Vertex) {
	if (GetDevice()->IsToggleEnabled(Toggle::UseTintGenerator)) {
	DAWN_TRY_ASSIGN(pullingSpirv,
	GeneratePullingSpirv(GetTintProgram(), *vertexState, entryPointName,
	kPullingBufferBindingSet));
	} else {
	DAWN_TRY_ASSIGN(pullingSpirv,
	GeneratePullingSpirv(GetSpirv(), *vertexState, entryPointName,
	kPullingBufferBindingSet));
	}
	spirv = &pullingSpirv;
	}

	// If these options are changed, the values in DawnSPIRVCrossMSLFastFuzzer.cpp need to
	// be updated.
	spirv_cross::CompilerMSL::Options options_msl;

	// Disable PointSize builtin for https://bugs.chromium.org/p/dawn/issues/detail?id=146
	// Because Metal will reject PointSize builtin if the shader is compiled into a render
	// pipeline that uses a non-point topology.
	// TODO (hao.x.li@intel.com): Remove this once WebGPU requires there is no
	// gl_PointSize builtin (https://github.com/gpuweb/gpuweb/issues/332).
	options_msl.enable_point_size_builtin = false;

	// Always use vertex buffer 30 (the last one in the vertex buffer table) to contain
	// the shader storage buffer lengths.
	options_msl.buffer_size_buffer_index = kBufferLengthBufferSlot;

	options_msl.additional_fixed_sample_mask = sampleMask;

	spirv_cross::CompilerMSL compiler(*spirv);
	compiler.set_msl_options(options_msl);
	compiler.set_entry_point(entryPointName, executionModel);

	// By default SPIRV-Cross will give MSL resources indices in increasing order.
	// To make the MSL indices match the indices chosen in the PipelineLayout, we build
	// a table of MSLResourceBinding to give to SPIRV-Cross.

	// Create one resource binding entry per stage per binding.
	for (BindGroupIndex group : IterateBitSet(layout->GetBindGroupLayoutsMask())) {
	const BindGroupLayoutBase::BindingMap& bindingMap =
	layout->GetBindGroupLayout(group)->GetBindingMap();

	for (const auto& it : bindingMap) {
	BindingNumber bindingNumber = it.first;
	BindingIndex bindingIndex = it.second;

	const BindingInfo& bindingInfo =
	layout->GetBindGroupLayout(group)->GetBindingInfo(bindingIndex);

	if (!(bindingInfo.visibility & StageBit(stage))) {
	continue;
	}

	uint32_t shaderIndex = layout->GetBindingIndexInfo(stage)[group][bindingIndex];

	spirv_cross::MSLResourceBinding mslBinding;
	mslBinding.stage = executionModel;
	mslBinding.desc_set = static_cast<uint32_t>(group);
	mslBinding.binding = static_cast<uint32_t>(bindingNumber);
	mslBinding.msl_buffer = mslBinding.msl_texture = mslBinding.msl_sampler =
	shaderIndex;

	compiler.add_msl_resource_binding(mslBinding);
	}
	}

	// Add vertex buffers bound as storage buffers
	if (GetDevice()->IsToggleEnabled(Toggle::MetalEnableVertexPulling) &&
	stage == SingleShaderStage::Vertex) {
	for (VertexBufferSlot slot :
	IterateBitSet(renderPipeline->GetVertexBufferSlotsUsed())) {
	uint32_t metalIndex = renderPipeline->GetMtlVertexBufferIndex(slot);

	spirv_cross::MSLResourceBinding mslBinding;

	mslBinding.stage = spv::ExecutionModelVertex;
	mslBinding.desc_set = static_cast<uint32_t>(kPullingBufferBindingSet);
	mslBinding.binding = static_cast<uint8_t>(slot);
	mslBinding.msl_buffer = metalIndex;
	compiler.add_msl_resource_binding(mslBinding);
	}
	}

	// SPIRV-Cross also supports re-ordering attributes but it seems to do the correct thing
	// by default.
	std::string msl = compiler.compile();

	// Some entry point names are forbidden in MSL so SPIRV-Cross modifies them. Query the
	// modified entryPointName from it.
	*remappedEntryPointName = compiler.get_entry_point(entryPointName, executionModel).name;
	*needsStorageBufferLength = compiler.needs_buffer_size_buffer();

	return std::move(msl);
	}

	MaybeError ShaderModule::CreateFunction(const char* entryPointName,
	SingleShaderStage stage,
	const PipelineLayout* layout,
	ShaderModule::MetalFunctionData* out,
	uint32_t sampleMask,
	const RenderPipeline* renderPipeline,
	const VertexState* vertexState) {
	ASSERT(!IsError());
	ASSERT(out);

	// Vertex stages must specify a renderPipeline and vertexState
	if (stage == SingleShaderStage::Vertex) {
	ASSERT(renderPipeline != nullptr);
	ASSERT(vertexState != nullptr);
	}

	std::string remappedEntryPointName;
	std::string msl;
	if (GetDevice()->IsToggleEnabled(Toggle::UseTintGenerator)) {
	DAWN_TRY_ASSIGN(
	msl, TranslateToMSLWithTint(entryPointName, stage, layout, sampleMask,
	renderPipeline, vertexState, &remappedEntryPointName,
	&out->needsStorageBufferLength));
	} else {
	DAWN_TRY_ASSIGN(msl, TranslateToMSLWithSPIRVCross(entryPointName, stage, layout,
	sampleMask, renderPipeline,
	vertexState, &remappedEntryPointName,
	&out->needsStorageBufferLength));
	}

	// Metal uses Clang to compile the shader as C++14. Disable everything in the -Wall
	// category. -Wunused-variable in particular comes up a lot in generated code, and some
	// (old?) Metal drivers accidentally treat it as a MTLLibraryErrorCompileError instead
	// of a warning.
	msl = R"(\
	#ifdef __clang__
	#pragma clang diagnostic ignored "-Wall"
	#endif
	)" + msl;

	NSRef<NSString> mslSource = AcquireNSRef([[NSString alloc] initWithUTF8String:msl.c_str()]);

	auto mtlDevice = ToBackend(GetDevice())->GetMTLDevice();
	NSError* error = nullptr;
	NSPRef<id<MTLLibrary>> library =
	AcquireNSPRef([mtlDevice newLibraryWithSource:mslSource.Get()
	options:nullptr
	error:&error]);
	if (error != nullptr) {
	if (error.code != MTLLibraryErrorCompileWarning) {
	const char* errorString = [error.localizedDescription UTF8String];
	return DAWN_VALIDATION_ERROR(std::string("Unable to create library object: ") +
	errorString);
	}
	}

	NSRef<NSString> name =
	AcquireNSRef([[NSString alloc] initWithUTF8String:remappedEntryPointName.c_str()]);
	out->function = AcquireNSPRef([*library newFunctionWithName:name.Get()]);

	if (GetDevice()->IsToggleEnabled(Toggle::MetalEnableVertexPulling) &&
	GetEntryPoint(entryPointName).usedVertexAttributes.any()) {
	out->needsStorageBufferLength = true;
	}

	return {};
	}
	}} // namespace dawn_native::metal