MoltenVKShaderConverter/MoltenVKShaderConverter/SPIRVToMSLConverter.cpp - external/github.com/KhronosGroup/MoltenVK - Git at Google

 /*
  * SPIRVToMSLConverter.cpp
  *
  * Copyright (c) 2015-2022 The Brenwill Workshop Ltd. (http://www.brenwill.com)
  *
  * 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 "SPIRVToMSLConverter.h"
 #include "MVKCommonEnvironment.h"
 #include "MVKStrings.h"
 #include "FileSupport.h"
 #include "SPIRVSupport.h"
 #include <fstream>

 using namespace mvk;
 using namespace std;
 using namespace spv;
 using namespace SPIRV_CROSS_NAMESPACE;


 #pragma mark -
 #pragma mark SPIRVToMSLConversionConfiguration

 // Returns whether the container contains an item equal to the value.
 template<class C, class T>
 bool contains(const C& container, const T& val) {
 	for (const T& cVal : container) { if (cVal == val) { return true; } }
 	return false;
 }

 // Returns whether the vector contains the value (using a matches(T&) comparison member function). */
 template<class T>
 bool containsMatching(const vector<T>& vec, const T& val) {
     for (const T& vecVal : vec) { if (vecVal.matches(val)) { return true; } }
     return false;
 }

 MVK_PUBLIC_SYMBOL bool SPIRVToMSLConversionOptions::matches(const SPIRVToMSLConversionOptions& other) const {
 	if (memcmp(&mslOptions, &other.mslOptions, sizeof(mslOptions)) != 0) { return false; }
 	if (entryPointStage != other.entryPointStage) { return false; }
 	if (entryPointName != other.entryPointName) { return false; }
 	if (tessPatchKind != other.tessPatchKind) { return false; }
 	if (numTessControlPoints != other.numTessControlPoints) { return false; }
 	if (shouldFlipVertexY != other.shouldFlipVertexY) { return false; }
 	return true;
 }

 MVK_PUBLIC_SYMBOL string SPIRVToMSLConversionOptions::printMSLVersion(uint32_t mslVersion, bool includePatch) {
 	string verStr;

 	uint32_t major = mslVersion / 10000;
 	verStr += to_string(major);

 	uint32_t minor = (mslVersion - CompilerMSL::Options::make_msl_version(major)) / 100;
 	verStr += ".";
 	verStr += to_string(minor);

 	if (includePatch) {
 		uint32_t patch = mslVersion - CompilerMSL::Options::make_msl_version(major, minor);
 		verStr += ".";
 		verStr += to_string(patch);
 	}

 	return verStr;
 }

 MVK_PUBLIC_SYMBOL SPIRVToMSLConversionOptions::SPIRVToMSLConversionOptions() {
 	// Explicitly set mslOptions to defaults over cleared memory to ensure all instances
 	// have exactly the same memory layout when using memory comparison in matches().
 	memset(&mslOptions, 0, sizeof(mslOptions));
 	mslOptions = CompilerMSL::Options();

 #if MVK_MACOS
 	mslOptions.platform = CompilerMSL::Options::macOS;
 #endif
 #if MVK_IOS
 	mslOptions.platform = CompilerMSL::Options::iOS;
 #endif
 #if MVK_TVOS
  	mslOptions.platform = CompilerMSL::Options::iOS;
 #endif

 	mslOptions.pad_fragment_output_components = true;
 }

 MVK_PUBLIC_SYMBOL bool mvk::MSLShaderInput::matches(const mvk::MSLShaderInput& other) const {
 	if (memcmp(&shaderInput, &other.shaderInput, sizeof(shaderInput)) != 0) { return false; }
 	if (binding != other.binding) { return false; }
 	return true;
 }

 MVK_PUBLIC_SYMBOL mvk::MSLShaderInput::MSLShaderInput() {
 	// Explicitly set shaderInput to defaults over cleared memory to ensure all instances
 	// have exactly the same memory layout when using memory comparison in matches().
 	memset(&shaderInput, 0, sizeof(shaderInput));
 	shaderInput = SPIRV_CROSS_NAMESPACE::MSLShaderInput();
 }

 // If requiresConstExprSampler is false, constExprSampler can be ignored
 MVK_PUBLIC_SYMBOL bool mvk::MSLResourceBinding::matches(const MSLResourceBinding& other) const {
 	if (memcmp(&resourceBinding, &other.resourceBinding, sizeof(resourceBinding)) != 0) { return false; }
 	if (requiresConstExprSampler != other.requiresConstExprSampler) { return false; }
 	if (requiresConstExprSampler) {
 		if (memcmp(&constExprSampler, &other.constExprSampler, sizeof(constExprSampler)) != 0) { return false; }
 	}
 	return true;
 }

 MVK_PUBLIC_SYMBOL mvk::MSLResourceBinding::MSLResourceBinding() {
 	// Explicitly set resourceBinding and constExprSampler to defaults over cleared memory to ensure
 	// all instances have exactly the same memory layout when using memory comparison in matches().
 	memset(&resourceBinding, 0, sizeof(resourceBinding));
 	resourceBinding = SPIRV_CROSS_NAMESPACE::MSLResourceBinding();
 	memset(&constExprSampler, 0, sizeof(constExprSampler));
 	constExprSampler = SPIRV_CROSS_NAMESPACE::MSLConstexprSampler();
 }

 MVK_PUBLIC_SYMBOL bool mvk::DescriptorBinding::matches(const mvk::DescriptorBinding& other) const {
 	if (stage != other.stage) { return false; }
 	if (descriptorSet != other.descriptorSet) { return false; }
 	if (binding != other.binding) { return false; }
 	if (index != other.index) { return false; }
 	return true;
 }

 MVK_PUBLIC_SYMBOL bool SPIRVToMSLConversionConfiguration::stageSupportsVertexAttributes() const {
 	return (options.entryPointStage == ExecutionModelVertex ||
 			options.entryPointStage == ExecutionModelTessellationControl ||
 			options.entryPointStage == ExecutionModelTessellationEvaluation);
 }

 // Check them all in case inactive VA's duplicate locations used by active VA's.
 MVK_PUBLIC_SYMBOL bool SPIRVToMSLConversionConfiguration::isShaderInputLocationUsed(uint32_t location) const {
     for (auto& si : shaderInputs) {
         if ((si.shaderInput.location == location) && si.outIsUsedByShader) { return true; }
     }
     return false;
 }

 MVK_PUBLIC_SYMBOL uint32_t SPIRVToMSLConversionConfiguration::countShaderInputsAt(uint32_t binding) const {
 	uint32_t siCnt = 0;
 	for (auto& si : shaderInputs) {
 		if ((si.binding == binding) && si.outIsUsedByShader) { siCnt++; }
 	}
 	return siCnt;
 }

 MVK_PUBLIC_SYMBOL bool SPIRVToMSLConversionConfiguration::isResourceUsed(ExecutionModel stage, uint32_t descSet, uint32_t binding) const {
 	for (auto& rb : resourceBindings) {
 		auto& rbb = rb.resourceBinding;
 		if (rbb.stage == stage && rbb.desc_set == descSet && rbb.binding == binding) {
 			return rb.outIsUsedByShader;
 		}
 	}
 	return false;
 }

 MVK_PUBLIC_SYMBOL void SPIRVToMSLConversionConfiguration::markAllInputsAndResourcesUsed() {
 	for (auto& si : shaderInputs) { si.outIsUsedByShader = true; }
 	for (auto& rb : resourceBindings) { rb.outIsUsedByShader = true; }
 }

 // A single SPIRVToMSLConversionConfiguration instance is used for all pipeline shader stages,
 // and the resources can be spread across these shader stages. To improve cache hits when using
 // this function to find a cached shader for a particular shader stage, only consider the resources
 // that are used in that shader stage. By contrast, discreteDescriptorSet apply across all stages,
 // and shaderInputs are populated before each stage, so neither needs to be filtered by stage here.
 MVK_PUBLIC_SYMBOL bool SPIRVToMSLConversionConfiguration::matches(const SPIRVToMSLConversionConfiguration& other) const {

     if ( !options.matches(other.options) ) { return false; }

 	for (const auto& si : shaderInputs) {
 		if (si.outIsUsedByShader && !containsMatching(other.shaderInputs, si)) { return false; }
 	}

     for (const auto& rb : resourceBindings) {
         if (rb.resourceBinding.stage == options.entryPointStage &&
 			rb.outIsUsedByShader &&
 			!containsMatching(other.resourceBindings, rb)) { return false; }
     }

 	for (const auto& db : dynamicBufferDescriptors) {
 		if (db.stage == options.entryPointStage &&
 			!containsMatching(other.dynamicBufferDescriptors, db)) { return false; }
 	}

 	for (uint32_t dsIdx : discreteDescriptorSets) {
 		if ( !contains(other.discreteDescriptorSets, dsIdx)) { return false; }
 	}

     return true;
 }


 MVK_PUBLIC_SYMBOL void SPIRVToMSLConversionConfiguration::alignWith(const SPIRVToMSLConversionConfiguration& srcContext) {

 	for (auto& si : shaderInputs) {
 		si.outIsUsedByShader = false;
 		for (auto& srcSI : srcContext.shaderInputs) {
 			if (si.matches(srcSI)) { si.outIsUsedByShader = srcSI.outIsUsedByShader; }
 		}
 	}

     for (auto& rb : resourceBindings) {
         rb.outIsUsedByShader = false;
         for (auto& srcRB : srcContext.resourceBindings) {
 			if (rb.matches(srcRB)) {
 				rb.outIsUsedByShader = srcRB.outIsUsedByShader;
 			}
         }
     }
 }


 #pragma mark -
 #pragma mark SPIRVToMSLConverter

 MVK_PUBLIC_SYMBOL void SPIRVToMSLConverter::setSPIRV(const uint32_t* spirvCode, size_t length) {
 	_spirv.clear();			// Clear for reuse
 	_spirv.reserve(length);
 	for (size_t i = 0; i < length; i++) {
 		_spirv.push_back(spirvCode[i]);
 	}
 }

 MVK_PUBLIC_SYMBOL bool SPIRVToMSLConverter::convert(SPIRVToMSLConversionConfiguration& shaderConfig,
 													bool shouldLogSPIRV,
 													bool shouldLogMSL,
                                                     bool shouldLogGLSL) {

 	// Uncomment to write SPIR-V to file as a debugging aid
 //	ofstream spvFile("spirv.spv", ios::binary);
 //	spvFile.write((char*)_spirv.data(), _spirv.size() << 2);
 //	spvFile.close();

 	_wasConverted = true;
 	_resultLog.clear();
 	_msl.clear();
 	_shaderConversionResults.reset();

 	if (shouldLogSPIRV) { logSPIRV("Converting"); }

 	CompilerMSL* pMSLCompiler = nullptr;

 #ifndef SPIRV_CROSS_EXCEPTIONS_TO_ASSERTIONS
 	try {
 #endif
 		pMSLCompiler = new CompilerMSL(_spirv);

 		if (shaderConfig.options.hasEntryPoint()) {
 			pMSLCompiler->set_entry_point(shaderConfig.options.entryPointName, shaderConfig.options.entryPointStage);
 		}

 		// Set up tessellation parameters if needed.
 		if (shaderConfig.options.entryPointStage == ExecutionModelTessellationControl ||
 			shaderConfig.options.entryPointStage == ExecutionModelTessellationEvaluation) {
 			if (shaderConfig.options.tessPatchKind != ExecutionModeMax) {
 				pMSLCompiler->set_execution_mode(shaderConfig.options.tessPatchKind);
 			}
 			if (shaderConfig.options.numTessControlPoints != 0) {
 				pMSLCompiler->set_execution_mode(ExecutionModeOutputVertices, shaderConfig.options.numTessControlPoints);
 			}
 		}

 		// Establish the MSL options for the compiler
 		// This needs to be done in two steps...for CompilerMSL and its superclass.
 		pMSLCompiler->set_msl_options(shaderConfig.options.mslOptions);

 		auto scOpts = pMSLCompiler->get_common_options();
 		scOpts.vertex.flip_vert_y = shaderConfig.options.shouldFlipVertexY;
 		pMSLCompiler->set_common_options(scOpts);

 		// Add shader inputs
 		for (auto& si : shaderConfig.shaderInputs) {
 			pMSLCompiler->add_msl_shader_input(si.shaderInput);
 		}

 		// Add resource bindings and hardcoded constexpr samplers
 		for (auto& rb : shaderConfig.resourceBindings) {
 			auto& rbb = rb.resourceBinding;
 			pMSLCompiler->add_msl_resource_binding(rbb);

 			if (rb.requiresConstExprSampler) {
 				pMSLCompiler->remap_constexpr_sampler_by_binding(rbb.desc_set, rbb.binding, rb.constExprSampler);
 			}
 		}

 		// Add any descriptor sets that are not using Metal argument buffers.
 		// This only has an effect if SPIRVToMSLConversionConfiguration::options::mslOptions::argument_buffers is enabled.
 		for (uint32_t dsIdx : shaderConfig.discreteDescriptorSets) {
 			pMSLCompiler->add_discrete_descriptor_set(dsIdx);
 		}

 		// Add any dynamic buffer bindings.
 		// This only has an applies if SPIRVToMSLConversionConfiguration::options::mslOptions::argument_buffers is enabled.
 		if (shaderConfig.options.mslOptions.argument_buffers) {
 			for (auto& db : shaderConfig.dynamicBufferDescriptors) {
 				if (db.stage == shaderConfig.options.entryPointStage) {
 					pMSLCompiler->add_dynamic_buffer(db.descriptorSet, db.binding, db.index);
 				}
 			}
 		}
 		_msl = pMSLCompiler->compile();

         if (shouldLogMSL) { logSource(_msl, "MSL", "Converted"); }

 #ifndef SPIRV_CROSS_EXCEPTIONS_TO_ASSERTIONS
 	} catch (CompilerError& ex) {
 		string errMsg("MSL conversion error: ");
 		errMsg += ex.what();
 		logError(errMsg.data());
         if (shouldLogMSL && pMSLCompiler) {
             _msl = pMSLCompiler->get_partial_source();
             logSource(_msl, "MSL", "Partially converted");
         }
 	}
 #endif

 	// Populate the shader conversion results with info from the compilation run,
 	// and mark which vertex attributes and resource bindings are used by the shader
 	populateEntryPoint(pMSLCompiler, shaderConfig.options);
 	_shaderConversionResults.isRasterizationDisabled = pMSLCompiler && pMSLCompiler->get_is_rasterization_disabled();
 	_shaderConversionResults.isPositionInvariant = pMSLCompiler && pMSLCompiler->is_position_invariant();
 	_shaderConversionResults.needsSwizzleBuffer = pMSLCompiler && pMSLCompiler->needs_swizzle_buffer();
 	_shaderConversionResults.needsOutputBuffer = pMSLCompiler && pMSLCompiler->needs_output_buffer();
 	_shaderConversionResults.needsPatchOutputBuffer = pMSLCompiler && pMSLCompiler->needs_patch_output_buffer();
 	_shaderConversionResults.needsBufferSizeBuffer = pMSLCompiler && pMSLCompiler->needs_buffer_size_buffer();
 	_shaderConversionResults.needsInputThreadgroupMem = pMSLCompiler && pMSLCompiler->needs_input_threadgroup_mem();
 	_shaderConversionResults.needsDispatchBaseBuffer = pMSLCompiler && pMSLCompiler->needs_dispatch_base_buffer();
 	_shaderConversionResults.needsViewRangeBuffer = pMSLCompiler && pMSLCompiler->needs_view_mask_buffer();

 	// When using Metal argument buffers, if the shader is provided with dynamic buffer offsets,
 	// then it needs a buffer to hold these dynamic offsets.
 	_shaderConversionResults.needsDynamicOffsetBuffer = false;
 	if (shaderConfig.options.mslOptions.argument_buffers) {
 		for (auto& db : shaderConfig.dynamicBufferDescriptors) {
 			if (db.stage == shaderConfig.options.entryPointStage) {
 				_shaderConversionResults.needsDynamicOffsetBuffer = true;
 			}
 		}
 	}

 	for (auto& ctxSI : shaderConfig.shaderInputs) {
 		ctxSI.outIsUsedByShader = pMSLCompiler->is_msl_shader_input_used(ctxSI.shaderInput.location);
 	}
 	for (auto& ctxRB : shaderConfig.resourceBindings) {
 		if (ctxRB.resourceBinding.stage == shaderConfig.options.entryPointStage) {
 			ctxRB.outIsUsedByShader = pMSLCompiler->is_msl_resource_binding_used(ctxRB.resourceBinding.stage,
 																				 ctxRB.resourceBinding.desc_set,
 																				 ctxRB.resourceBinding.binding);
 		}
 	}

 	delete pMSLCompiler;

     // To check GLSL conversion
     if (shouldLogGLSL) {
 		CompilerGLSL* pGLSLCompiler = nullptr;

 #ifndef SPIRV_CROSS_EXCEPTIONS_TO_ASSERTIONS
 		try {
 #endif
 			pGLSLCompiler = new CompilerGLSL(_spirv);
 			auto options = pGLSLCompiler->get_common_options();
 			options.vulkan_semantics = true;
 			options.separate_shader_objects = true;
 			pGLSLCompiler->set_common_options(options);
 			string glsl = pGLSLCompiler->compile();
             logSource(glsl, "GLSL", "Estimated original");
 #ifndef SPIRV_CROSS_EXCEPTIONS_TO_ASSERTIONS
         } catch (CompilerError& ex) {
             string errMsg("Original GLSL extraction error: ");
             errMsg += ex.what();
             logMsg(errMsg.data());
 			if (pGLSLCompiler) {
 				string glsl = pGLSLCompiler->get_partial_source();
 				logSource(glsl, "GLSL", "Partially converted");
 			}
         }
 #endif
 		delete pGLSLCompiler;
 	}

 	return _wasConverted;
 }

 // Appends the message text to the result log.
 void SPIRVToMSLConverter::logMsg(const char* logMsg) {
 	string trimMsg = trim(logMsg);
 	if ( !trimMsg.empty() ) {
 		_resultLog += trimMsg;
 		_resultLog += "\n\n";
 	}
 }

 // Appends the error text to the result log, sets the wasConverted property to false, and returns it.
 bool SPIRVToMSLConverter::logError(const char* errMsg) {
 	logMsg(errMsg);
 	_wasConverted = false;
 	return _wasConverted;
 }

 // Appends the SPIR-V to the result log, indicating whether it is being converted or was converted.
 void SPIRVToMSLConverter::logSPIRV(const char* opDesc) {

 	string spvLog;
 	mvk::logSPIRV(_spirv, spvLog);

 	_resultLog += opDesc;
 	_resultLog += " SPIR-V:\n";
 	_resultLog += spvLog;
 	_resultLog += "\nEnd SPIR-V\n\n";

 	// Uncomment one or both of the following lines to get additional debugging and tracability capabilities.
 	// The SPIR-V can be written in binary form to a file, and/or logged in human readable form to the console.
 	// These can be helpful if errors occur during conversion of SPIR-V to MSL.
 //	writeSPIRVToFile("spvout.spv");
 //	printf("\n%s\n", getResultLog().c_str());
 }

 // Writes the SPIR-V code to a file. This can be useful for debugging
 // when the SPRIR-V did not originally come from a known file
 void SPIRVToMSLConverter::writeSPIRVToFile(string spvFilepath) {
 	vector<char> fileContents;
 	spirvToBytes(_spirv, fileContents);
 	string errMsg;
 	if (writeFile(spvFilepath, fileContents, errMsg)) {
 		_resultLog += "Saved SPIR-V to file: " + absolutePath(spvFilepath) + "\n\n";
 	} else {
 		_resultLog += "Could not write SPIR-V file. " + errMsg + "\n\n";
 	}
 }

 // Validates that the SPIR-V code will disassemble during logging.
 bool SPIRVToMSLConverter::validateSPIRV() {
 	if (_spirv.size() < 5) { return false; }
 	if (_spirv[0] != MagicNumber) { return false; }
 	if (_spirv[4] != 0) { return false; }
 	return true;
 }

 // Appends the source to the result log, prepending with the operation.
 void SPIRVToMSLConverter::logSource(string& src, const char* srcLang, const char* opDesc) {
     _resultLog += opDesc;
     _resultLog += " ";
     _resultLog += srcLang;
     _resultLog += ":\n";
     _resultLog += src;
     _resultLog += "\nEnd ";
     _resultLog += srcLang;
     _resultLog += "\n\n";
 }

 void SPIRVToMSLConverter::populateWorkgroupDimension(SPIRVWorkgroupSizeDimension& wgDim,
 													 uint32_t size,
 													 SpecializationConstant& spvSpecConst) {
 	wgDim.size = max(size, 1u);
 	wgDim.isSpecialized = (uint32_t(spvSpecConst.id) != 0);
 	wgDim.specializationID = spvSpecConst.constant_id;
 }

 // Populates the entry point with info extracted from the SPRI-V compiler.
 void SPIRVToMSLConverter::populateEntryPoint(Compiler* pCompiler,
 											 SPIRVToMSLConversionOptions& options) {

 	if ( !pCompiler ) { return; }

 	SPIREntryPoint spvEP;
 	if (options.hasEntryPoint()) {
 		spvEP = pCompiler->get_entry_point(options.entryPointName, options.entryPointStage);
 	} else {
 		const auto& entryPoints = pCompiler->get_entry_points_and_stages();
 		if ( !entryPoints.empty() ) {
 			auto& ep = entryPoints[0];
 			spvEP = pCompiler->get_entry_point(ep.name, ep.execution_model);
 		}
 	}

 	auto& ep = _shaderConversionResults.entryPoint;
 	ep.mtlFunctionName = spvEP.name;
 	ep.supportsFastMath = !spvEP.flags.get(ExecutionModeSignedZeroInfNanPreserve);

 	SpecializationConstant widthSC, heightSC, depthSC;
 	pCompiler->get_work_group_size_specialization_constants(widthSC, heightSC, depthSC);

 	auto& wgSize = ep.workgroupSize;
 	populateWorkgroupDimension(wgSize.width, spvEP.workgroup_size.x, widthSC);
 	populateWorkgroupDimension(wgSize.height, spvEP.workgroup_size.y, heightSC);
 	populateWorkgroupDimension(wgSize.depth, spvEP.workgroup_size.z, depthSC);
 }
	/*
	* SPIRVToMSLConverter.cpp
	*
	* Copyright (c) 2015-2022 The Brenwill Workshop Ltd. (http://www.brenwill.com)
	*
	* 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 "SPIRVToMSLConverter.h"
	#include "MVKCommonEnvironment.h"
	#include "MVKStrings.h"
	#include "FileSupport.h"
	#include "SPIRVSupport.h"
	#include <fstream>

	using namespace mvk;
	using namespace std;
	using namespace spv;
	using namespace SPIRV_CROSS_NAMESPACE;


	#pragma mark -
	#pragma mark SPIRVToMSLConversionConfiguration

	// Returns whether the container contains an item equal to the value.
	template<class C, class T>
	bool contains(const C& container, const T& val) {
	for (const T& cVal : container) { if (cVal == val) { return true; } }
	return false;
	}

	// Returns whether the vector contains the value (using a matches(T&) comparison member function). */
	template<class T>
	bool containsMatching(const vector<T>& vec, const T& val) {
	for (const T& vecVal : vec) { if (vecVal.matches(val)) { return true; } }
	return false;
	}

	MVK_PUBLIC_SYMBOL bool SPIRVToMSLConversionOptions::matches(const SPIRVToMSLConversionOptions& other) const {
	if (memcmp(&mslOptions, &other.mslOptions, sizeof(mslOptions)) != 0) { return false; }
	if (entryPointStage != other.entryPointStage) { return false; }
	if (entryPointName != other.entryPointName) { return false; }
	if (tessPatchKind != other.tessPatchKind) { return false; }
	if (numTessControlPoints != other.numTessControlPoints) { return false; }
	if (shouldFlipVertexY != other.shouldFlipVertexY) { return false; }
	return true;
	}

	MVK_PUBLIC_SYMBOL string SPIRVToMSLConversionOptions::printMSLVersion(uint32_t mslVersion, bool includePatch) {
	string verStr;

	uint32_t major = mslVersion / 10000;
	verStr += to_string(major);

	uint32_t minor = (mslVersion - CompilerMSL::Options::make_msl_version(major)) / 100;
	verStr += ".";
	verStr += to_string(minor);

	if (includePatch) {
	uint32_t patch = mslVersion - CompilerMSL::Options::make_msl_version(major, minor);
	verStr += ".";
	verStr += to_string(patch);
	}

	return verStr;
	}

	MVK_PUBLIC_SYMBOL SPIRVToMSLConversionOptions::SPIRVToMSLConversionOptions() {
	// Explicitly set mslOptions to defaults over cleared memory to ensure all instances
	// have exactly the same memory layout when using memory comparison in matches().
	memset(&mslOptions, 0, sizeof(mslOptions));
	mslOptions = CompilerMSL::Options();

	#if MVK_MACOS
	mslOptions.platform = CompilerMSL::Options::macOS;
	#endif
	#if MVK_IOS
	mslOptions.platform = CompilerMSL::Options::iOS;
	#endif
	#if MVK_TVOS
	mslOptions.platform = CompilerMSL::Options::iOS;
	#endif

	mslOptions.pad_fragment_output_components = true;
	}

	MVK_PUBLIC_SYMBOL bool mvk::MSLShaderInput::matches(const mvk::MSLShaderInput& other) const {
	if (memcmp(&shaderInput, &other.shaderInput, sizeof(shaderInput)) != 0) { return false; }
	if (binding != other.binding) { return false; }
	return true;
	}

	MVK_PUBLIC_SYMBOL mvk::MSLShaderInput::MSLShaderInput() {
	// Explicitly set shaderInput to defaults over cleared memory to ensure all instances
	// have exactly the same memory layout when using memory comparison in matches().
	memset(&shaderInput, 0, sizeof(shaderInput));
	shaderInput = SPIRV_CROSS_NAMESPACE::MSLShaderInput();
	}

	// If requiresConstExprSampler is false, constExprSampler can be ignored
	MVK_PUBLIC_SYMBOL bool mvk::MSLResourceBinding::matches(const MSLResourceBinding& other) const {
	if (memcmp(&resourceBinding, &other.resourceBinding, sizeof(resourceBinding)) != 0) { return false; }
	if (requiresConstExprSampler != other.requiresConstExprSampler) { return false; }
	if (requiresConstExprSampler) {
	if (memcmp(&constExprSampler, &other.constExprSampler, sizeof(constExprSampler)) != 0) { return false; }
	}
	return true;
	}

	MVK_PUBLIC_SYMBOL mvk::MSLResourceBinding::MSLResourceBinding() {
	// Explicitly set resourceBinding and constExprSampler to defaults over cleared memory to ensure
	// all instances have exactly the same memory layout when using memory comparison in matches().
	memset(&resourceBinding, 0, sizeof(resourceBinding));
	resourceBinding = SPIRV_CROSS_NAMESPACE::MSLResourceBinding();
	memset(&constExprSampler, 0, sizeof(constExprSampler));
	constExprSampler = SPIRV_CROSS_NAMESPACE::MSLConstexprSampler();
	}

	MVK_PUBLIC_SYMBOL bool mvk::DescriptorBinding::matches(const mvk::DescriptorBinding& other) const {
	if (stage != other.stage) { return false; }
	if (descriptorSet != other.descriptorSet) { return false; }
	if (binding != other.binding) { return false; }
	if (index != other.index) { return false; }
	return true;
	}

	MVK_PUBLIC_SYMBOL bool SPIRVToMSLConversionConfiguration::stageSupportsVertexAttributes() const {
	return (options.entryPointStage == ExecutionModelVertex \|\|
	options.entryPointStage == ExecutionModelTessellationControl \|\|
	options.entryPointStage == ExecutionModelTessellationEvaluation);
	}

	// Check them all in case inactive VA's duplicate locations used by active VA's.
	MVK_PUBLIC_SYMBOL bool SPIRVToMSLConversionConfiguration::isShaderInputLocationUsed(uint32_t location) const {
	for (auto& si : shaderInputs) {
	if ((si.shaderInput.location == location) && si.outIsUsedByShader) { return true; }
	}
	return false;
	}

	MVK_PUBLIC_SYMBOL uint32_t SPIRVToMSLConversionConfiguration::countShaderInputsAt(uint32_t binding) const {
	uint32_t siCnt = 0;
	for (auto& si : shaderInputs) {
	if ((si.binding == binding) && si.outIsUsedByShader) { siCnt++; }
	}
	return siCnt;
	}

	MVK_PUBLIC_SYMBOL bool SPIRVToMSLConversionConfiguration::isResourceUsed(ExecutionModel stage, uint32_t descSet, uint32_t binding) const {
	for (auto& rb : resourceBindings) {
	auto& rbb = rb.resourceBinding;
	if (rbb.stage == stage && rbb.desc_set == descSet && rbb.binding == binding) {
	return rb.outIsUsedByShader;
	}
	}
	return false;
	}

	MVK_PUBLIC_SYMBOL void SPIRVToMSLConversionConfiguration::markAllInputsAndResourcesUsed() {
	for (auto& si : shaderInputs) { si.outIsUsedByShader = true; }
	for (auto& rb : resourceBindings) { rb.outIsUsedByShader = true; }
	}

	// A single SPIRVToMSLConversionConfiguration instance is used for all pipeline shader stages,
	// and the resources can be spread across these shader stages. To improve cache hits when using
	// this function to find a cached shader for a particular shader stage, only consider the resources
	// that are used in that shader stage. By contrast, discreteDescriptorSet apply across all stages,
	// and shaderInputs are populated before each stage, so neither needs to be filtered by stage here.
	MVK_PUBLIC_SYMBOL bool SPIRVToMSLConversionConfiguration::matches(const SPIRVToMSLConversionConfiguration& other) const {

	if ( !options.matches(other.options) ) { return false; }

	for (const auto& si : shaderInputs) {
	if (si.outIsUsedByShader && !containsMatching(other.shaderInputs, si)) { return false; }
	}

	for (const auto& rb : resourceBindings) {
	if (rb.resourceBinding.stage == options.entryPointStage &&
	rb.outIsUsedByShader &&
	!containsMatching(other.resourceBindings, rb)) { return false; }
	}

	for (const auto& db : dynamicBufferDescriptors) {
	if (db.stage == options.entryPointStage &&
	!containsMatching(other.dynamicBufferDescriptors, db)) { return false; }
	}

	for (uint32_t dsIdx : discreteDescriptorSets) {
	if ( !contains(other.discreteDescriptorSets, dsIdx)) { return false; }
	}

	return true;
	}


	MVK_PUBLIC_SYMBOL void SPIRVToMSLConversionConfiguration::alignWith(const SPIRVToMSLConversionConfiguration& srcContext) {

	for (auto& si : shaderInputs) {
	si.outIsUsedByShader = false;
	for (auto& srcSI : srcContext.shaderInputs) {
	if (si.matches(srcSI)) { si.outIsUsedByShader = srcSI.outIsUsedByShader; }
	}
	}

	for (auto& rb : resourceBindings) {
	rb.outIsUsedByShader = false;
	for (auto& srcRB : srcContext.resourceBindings) {
	if (rb.matches(srcRB)) {
	rb.outIsUsedByShader = srcRB.outIsUsedByShader;
	}
	}
	}
	}


	#pragma mark -
	#pragma mark SPIRVToMSLConverter

	MVK_PUBLIC_SYMBOL void SPIRVToMSLConverter::setSPIRV(const uint32_t* spirvCode, size_t length) {
	_spirv.clear(); // Clear for reuse
	_spirv.reserve(length);
	for (size_t i = 0; i < length; i++) {
	_spirv.push_back(spirvCode[i]);
	}
	}

	MVK_PUBLIC_SYMBOL bool SPIRVToMSLConverter::convert(SPIRVToMSLConversionConfiguration& shaderConfig,
	bool shouldLogSPIRV,
	bool shouldLogMSL,
	bool shouldLogGLSL) {

	// Uncomment to write SPIR-V to file as a debugging aid
	// ofstream spvFile("spirv.spv", ios::binary);
	// spvFile.write((char*)_spirv.data(), _spirv.size() << 2);
	// spvFile.close();

	_wasConverted = true;
	_resultLog.clear();
	_msl.clear();
	_shaderConversionResults.reset();

	if (shouldLogSPIRV) { logSPIRV("Converting"); }

	CompilerMSL* pMSLCompiler = nullptr;

	#ifndef SPIRV_CROSS_EXCEPTIONS_TO_ASSERTIONS
	try {
	#endif
	pMSLCompiler = new CompilerMSL(_spirv);

	if (shaderConfig.options.hasEntryPoint()) {
	pMSLCompiler->set_entry_point(shaderConfig.options.entryPointName, shaderConfig.options.entryPointStage);
	}

	// Set up tessellation parameters if needed.
	if (shaderConfig.options.entryPointStage == ExecutionModelTessellationControl \|\|
	shaderConfig.options.entryPointStage == ExecutionModelTessellationEvaluation) {
	if (shaderConfig.options.tessPatchKind != ExecutionModeMax) {
	pMSLCompiler->set_execution_mode(shaderConfig.options.tessPatchKind);
	}
	if (shaderConfig.options.numTessControlPoints != 0) {
	pMSLCompiler->set_execution_mode(ExecutionModeOutputVertices, shaderConfig.options.numTessControlPoints);
	}
	}

	// Establish the MSL options for the compiler
	// This needs to be done in two steps...for CompilerMSL and its superclass.
	pMSLCompiler->set_msl_options(shaderConfig.options.mslOptions);

	auto scOpts = pMSLCompiler->get_common_options();
	scOpts.vertex.flip_vert_y = shaderConfig.options.shouldFlipVertexY;
	pMSLCompiler->set_common_options(scOpts);

	// Add shader inputs
	for (auto& si : shaderConfig.shaderInputs) {
	pMSLCompiler->add_msl_shader_input(si.shaderInput);
	}

	// Add resource bindings and hardcoded constexpr samplers
	for (auto& rb : shaderConfig.resourceBindings) {
	auto& rbb = rb.resourceBinding;
	pMSLCompiler->add_msl_resource_binding(rbb);

	if (rb.requiresConstExprSampler) {
	pMSLCompiler->remap_constexpr_sampler_by_binding(rbb.desc_set, rbb.binding, rb.constExprSampler);
	}
	}

	// Add any descriptor sets that are not using Metal argument buffers.
	// This only has an effect if SPIRVToMSLConversionConfiguration::options::mslOptions::argument_buffers is enabled.
	for (uint32_t dsIdx : shaderConfig.discreteDescriptorSets) {
	pMSLCompiler->add_discrete_descriptor_set(dsIdx);
	}

	// Add any dynamic buffer bindings.
	// This only has an applies if SPIRVToMSLConversionConfiguration::options::mslOptions::argument_buffers is enabled.
	if (shaderConfig.options.mslOptions.argument_buffers) {
	for (auto& db : shaderConfig.dynamicBufferDescriptors) {
	if (db.stage == shaderConfig.options.entryPointStage) {
	pMSLCompiler->add_dynamic_buffer(db.descriptorSet, db.binding, db.index);
	}
	}
	}
	_msl = pMSLCompiler->compile();

	if (shouldLogMSL) { logSource(_msl, "MSL", "Converted"); }

	#ifndef SPIRV_CROSS_EXCEPTIONS_TO_ASSERTIONS
	} catch (CompilerError& ex) {
	string errMsg("MSL conversion error: ");
	errMsg += ex.what();
	logError(errMsg.data());
	if (shouldLogMSL && pMSLCompiler) {
	_msl = pMSLCompiler->get_partial_source();
	logSource(_msl, "MSL", "Partially converted");
	}
	}
	#endif

	// Populate the shader conversion results with info from the compilation run,
	// and mark which vertex attributes and resource bindings are used by the shader
	populateEntryPoint(pMSLCompiler, shaderConfig.options);
	_shaderConversionResults.isRasterizationDisabled = pMSLCompiler && pMSLCompiler->get_is_rasterization_disabled();
	_shaderConversionResults.isPositionInvariant = pMSLCompiler && pMSLCompiler->is_position_invariant();
	_shaderConversionResults.needsSwizzleBuffer = pMSLCompiler && pMSLCompiler->needs_swizzle_buffer();
	_shaderConversionResults.needsOutputBuffer = pMSLCompiler && pMSLCompiler->needs_output_buffer();
	_shaderConversionResults.needsPatchOutputBuffer = pMSLCompiler && pMSLCompiler->needs_patch_output_buffer();
	_shaderConversionResults.needsBufferSizeBuffer = pMSLCompiler && pMSLCompiler->needs_buffer_size_buffer();
	_shaderConversionResults.needsInputThreadgroupMem = pMSLCompiler && pMSLCompiler->needs_input_threadgroup_mem();
	_shaderConversionResults.needsDispatchBaseBuffer = pMSLCompiler && pMSLCompiler->needs_dispatch_base_buffer();
	_shaderConversionResults.needsViewRangeBuffer = pMSLCompiler && pMSLCompiler->needs_view_mask_buffer();

	// When using Metal argument buffers, if the shader is provided with dynamic buffer offsets,
	// then it needs a buffer to hold these dynamic offsets.
	_shaderConversionResults.needsDynamicOffsetBuffer = false;
	if (shaderConfig.options.mslOptions.argument_buffers) {
	for (auto& db : shaderConfig.dynamicBufferDescriptors) {
	if (db.stage == shaderConfig.options.entryPointStage) {
	_shaderConversionResults.needsDynamicOffsetBuffer = true;
	}
	}
	}

	for (auto& ctxSI : shaderConfig.shaderInputs) {
	ctxSI.outIsUsedByShader = pMSLCompiler->is_msl_shader_input_used(ctxSI.shaderInput.location);
	}
	for (auto& ctxRB : shaderConfig.resourceBindings) {
	if (ctxRB.resourceBinding.stage == shaderConfig.options.entryPointStage) {
	ctxRB.outIsUsedByShader = pMSLCompiler->is_msl_resource_binding_used(ctxRB.resourceBinding.stage,
	ctxRB.resourceBinding.desc_set,
	ctxRB.resourceBinding.binding);
	}
	}

	delete pMSLCompiler;

	// To check GLSL conversion
	if (shouldLogGLSL) {
	CompilerGLSL* pGLSLCompiler = nullptr;

	#ifndef SPIRV_CROSS_EXCEPTIONS_TO_ASSERTIONS
	try {
	#endif
	pGLSLCompiler = new CompilerGLSL(_spirv);
	auto options = pGLSLCompiler->get_common_options();
	options.vulkan_semantics = true;
	options.separate_shader_objects = true;
	pGLSLCompiler->set_common_options(options);
	string glsl = pGLSLCompiler->compile();
	logSource(glsl, "GLSL", "Estimated original");
	#ifndef SPIRV_CROSS_EXCEPTIONS_TO_ASSERTIONS
	} catch (CompilerError& ex) {
	string errMsg("Original GLSL extraction error: ");
	errMsg += ex.what();
	logMsg(errMsg.data());
	if (pGLSLCompiler) {
	string glsl = pGLSLCompiler->get_partial_source();
	logSource(glsl, "GLSL", "Partially converted");
	}
	}
	#endif
	delete pGLSLCompiler;
	}

	return _wasConverted;
	}

	// Appends the message text to the result log.
	void SPIRVToMSLConverter::logMsg(const char* logMsg) {
	string trimMsg = trim(logMsg);
	if ( !trimMsg.empty() ) {
	_resultLog += trimMsg;
	_resultLog += "\n\n";
	}
	}

	// Appends the error text to the result log, sets the wasConverted property to false, and returns it.
	bool SPIRVToMSLConverter::logError(const char* errMsg) {
	logMsg(errMsg);
	_wasConverted = false;
	return _wasConverted;
	}

	// Appends the SPIR-V to the result log, indicating whether it is being converted or was converted.
	void SPIRVToMSLConverter::logSPIRV(const char* opDesc) {

	string spvLog;
	mvk::logSPIRV(_spirv, spvLog);

	_resultLog += opDesc;
	_resultLog += " SPIR-V:\n";
	_resultLog += spvLog;
	_resultLog += "\nEnd SPIR-V\n\n";

	// Uncomment one or both of the following lines to get additional debugging and tracability capabilities.
	// The SPIR-V can be written in binary form to a file, and/or logged in human readable form to the console.
	// These can be helpful if errors occur during conversion of SPIR-V to MSL.
	// writeSPIRVToFile("spvout.spv");
	// printf("\n%s\n", getResultLog().c_str());
	}

	// Writes the SPIR-V code to a file. This can be useful for debugging
	// when the SPRIR-V did not originally come from a known file
	void SPIRVToMSLConverter::writeSPIRVToFile(string spvFilepath) {
	vector<char> fileContents;
	spirvToBytes(_spirv, fileContents);
	string errMsg;
	if (writeFile(spvFilepath, fileContents, errMsg)) {
	_resultLog += "Saved SPIR-V to file: " + absolutePath(spvFilepath) + "\n\n";
	} else {
	_resultLog += "Could not write SPIR-V file. " + errMsg + "\n\n";
	}
	}

	// Validates that the SPIR-V code will disassemble during logging.
	bool SPIRVToMSLConverter::validateSPIRV() {
	if (_spirv.size() < 5) { return false; }
	if (_spirv[0] != MagicNumber) { return false; }
	if (_spirv[4] != 0) { return false; }
	return true;
	}

	// Appends the source to the result log, prepending with the operation.
	void SPIRVToMSLConverter::logSource(string& src, const char* srcLang, const char* opDesc) {
	_resultLog += opDesc;
	_resultLog += " ";
	_resultLog += srcLang;
	_resultLog += ":\n";
	_resultLog += src;
	_resultLog += "\nEnd ";
	_resultLog += srcLang;
	_resultLog += "\n\n";
	}

	void SPIRVToMSLConverter::populateWorkgroupDimension(SPIRVWorkgroupSizeDimension& wgDim,
	uint32_t size,
	SpecializationConstant& spvSpecConst) {
	wgDim.size = max(size, 1u);
	wgDim.isSpecialized = (uint32_t(spvSpecConst.id) != 0);
	wgDim.specializationID = spvSpecConst.constant_id;
	}

	// Populates the entry point with info extracted from the SPRI-V compiler.
	void SPIRVToMSLConverter::populateEntryPoint(Compiler* pCompiler,
	SPIRVToMSLConversionOptions& options) {

	if ( !pCompiler ) { return; }

	SPIREntryPoint spvEP;
	if (options.hasEntryPoint()) {
	spvEP = pCompiler->get_entry_point(options.entryPointName, options.entryPointStage);
	} else {
	const auto& entryPoints = pCompiler->get_entry_points_and_stages();
	if ( !entryPoints.empty() ) {
	auto& ep = entryPoints[0];
	spvEP = pCompiler->get_entry_point(ep.name, ep.execution_model);
	}
	}

	auto& ep = _shaderConversionResults.entryPoint;
	ep.mtlFunctionName = spvEP.name;
	ep.supportsFastMath = !spvEP.flags.get(ExecutionModeSignedZeroInfNanPreserve);

	SpecializationConstant widthSC, heightSC, depthSC;
	pCompiler->get_work_group_size_specialization_constants(widthSC, heightSC, depthSC);

	auto& wgSize = ep.workgroupSize;
	populateWorkgroupDimension(wgSize.width, spvEP.workgroup_size.x, widthSC);
	populateWorkgroupDimension(wgSize.height, spvEP.workgroup_size.y, heightSC);
	populateWorkgroupDimension(wgSize.depth, spvEP.workgroup_size.z, depthSC);
	}