src/dawn/native/opengl/ShaderModuleGL.cpp - dawn - Git at Google

 // Copyright 2017 The Dawn & Tint Authors
 //
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are met:
 //
 // 1. Redistributions of source code must retain the above copyright notice, this
 //    list of conditions and the following disclaimer.
 //
 // 2. Redistributions in binary form must reproduce the above copyright notice,
 //    this list of conditions and the following disclaimer in the documentation
 //    and/or other materials provided with the distribution.
 //
 // 3. Neither the name of the copyright holder nor the names of its
 //    contributors may be used to endorse or promote products derived from
 //    this software without specific prior written permission.
 //
 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 // AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 // IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 // DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
 // FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 // DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 // SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 // CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 // OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

 #include "dawn/native/opengl/ShaderModuleGL.h"

 #include <sstream>
 #include <unordered_map>
 #include <utility>

 #include "dawn/native/BindGroupLayoutInternal.h"
 #include "dawn/native/CacheRequest.h"
 #include "dawn/native/Pipeline.h"
 #include "dawn/native/TintUtils.h"
 #include "dawn/native/opengl/BindingPoint.h"
 #include "dawn/native/opengl/DeviceGL.h"
 #include "dawn/native/opengl/PipelineLayoutGL.h"
 #include "dawn/platform/DawnPlatform.h"
 #include "dawn/platform/tracing/TraceEvent.h"

 #include "tint/tint.h"

 namespace dawn::native {
 namespace {

 GLenum GLShaderType(SingleShaderStage stage) {
     switch (stage) {
         case SingleShaderStage::Vertex:
             return GL_VERTEX_SHADER;
         case SingleShaderStage::Fragment:
             return GL_FRAGMENT_SHADER;
         case SingleShaderStage::Compute:
             return GL_COMPUTE_SHADER;
     }
     DAWN_UNREACHABLE();
 }

 tint::glsl::writer::Version::Standard ToTintGLStandard(opengl::OpenGLVersion::Standard standard) {
     switch (standard) {
         case opengl::OpenGLVersion::Standard::Desktop:
             return tint::glsl::writer::Version::Standard::kDesktop;
         case opengl::OpenGLVersion::Standard::ES:
             return tint::glsl::writer::Version::Standard::kES;
     }
     DAWN_UNREACHABLE();
 }

 using BindingMap = std::unordered_map<tint::BindingPoint, tint::BindingPoint>;

 opengl::CombinedSampler* AppendCombinedSampler(opengl::CombinedSamplerInfo* info,
                                                tint::inspector::SamplerTexturePair pair,
                                                tint::BindingPoint placeholderBindingPoint) {
     info->emplace_back();
     opengl::CombinedSampler* combinedSampler = &info->back();
     combinedSampler->usePlaceholderSampler = pair.sampler_binding_point == placeholderBindingPoint;
     combinedSampler->samplerLocation.group = BindGroupIndex(pair.sampler_binding_point.group);
     combinedSampler->samplerLocation.binding = BindingNumber(pair.sampler_binding_point.binding);
     combinedSampler->textureLocation.group = BindGroupIndex(pair.texture_binding_point.group);
     combinedSampler->textureLocation.binding = BindingNumber(pair.texture_binding_point.binding);
     return combinedSampler;
 }

 using InterstageLocationAndName = std::pair<uint32_t, std::string>;

 #define GLSL_COMPILATION_REQUEST_MEMBERS(X)                                                      \
     X(const tint::Program*, inputProgram)                                                        \
     X(std::string, entryPointName)                                                               \
     X(SingleShaderStage, stage)                                                                  \
     X(std::optional<tint::ast::transform::SubstituteOverride::Config>, substituteOverrideConfig) \
     X(LimitsForCompilationRequest, limits)                                                       \
     X(bool, disableSymbolRenaming)                                                               \
     X(std::vector<InterstageLocationAndName>, interstageVariables)                               \
     X(std::vector<std::string>, bufferBindingVariables)                                          \
     X(tint::glsl::writer::Options, tintOptions)                                                  \
     X(CacheKey::UnsafeUnkeyedValue<dawn::platform::Platform*>, platform)

 DAWN_MAKE_CACHE_REQUEST(GLSLCompilationRequest, GLSL_COMPILATION_REQUEST_MEMBERS);
 #undef GLSL_COMPILATION_REQUEST_MEMBERS

 #define GLSL_COMPILATION_MEMBERS(X) X(std::string, glsl)

 DAWN_SERIALIZABLE(struct, GLSLCompilation, GLSL_COMPILATION_MEMBERS){};
 #undef GLSL_COMPILATION_MEMBERS

 }  // namespace
 }  // namespace dawn::native

 namespace dawn::native::opengl {

 std::string GetBindingName(BindGroupIndex group, BindingNumber bindingNumber) {
     std::ostringstream o;
     o << "dawn_binding_" << static_cast<uint32_t>(group) << "_"
       << static_cast<uint32_t>(bindingNumber);
     return o.str();
 }

 bool operator<(const BindingLocation& a, const BindingLocation& b) {
     return std::tie(a.group, a.binding) < std::tie(b.group, b.binding);
 }

 bool operator<(const CombinedSampler& a, const CombinedSampler& b) {
     return std::tie(a.usePlaceholderSampler, a.samplerLocation, a.textureLocation) <
            std::tie(b.usePlaceholderSampler, a.samplerLocation, b.textureLocation);
 }

 std::string CombinedSampler::GetName() const {
     std::ostringstream o;
     o << "dawn_combined";
     if (usePlaceholderSampler) {
         o << "_placeholder_sampler";
     } else {
         o << "_" << static_cast<uint32_t>(samplerLocation.group) << "_"
           << static_cast<uint32_t>(samplerLocation.binding);
     }
     o << "_with_" << static_cast<uint32_t>(textureLocation.group) << "_"
       << static_cast<uint32_t>(textureLocation.binding);
     return o.str();
 }

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

 ShaderModule::ShaderModule(Device* device, const UnpackedPtr<ShaderModuleDescriptor>& descriptor)
     : ShaderModuleBase(device, descriptor) {}

 MaybeError ShaderModule::Initialize(ShaderModuleParseResult* parseResult,
                                     OwnedCompilationMessages* compilationMessages) {
     ScopedTintICEHandler scopedICEHandler(GetDevice());

     DAWN_TRY(InitializeBase(parseResult, compilationMessages));

     return {};
 }

 ResultOrError<GLuint> ShaderModule::CompileShader(
     const OpenGLFunctions& gl,
     const ProgrammableStage& programmableStage,
     SingleShaderStage stage,
     bool usesInstanceIndex,
     bool usesFragDepth,
     CombinedSamplerInfo* combinedSamplers,
     const PipelineLayout* layout,
     bool* needsPlaceholderSampler,
     bool* needsTextureBuiltinUniformBuffer,
     BindingPointToFunctionAndOffset* bindingPointToData) const {
     TRACE_EVENT0(GetDevice()->GetPlatform(), General, "TranslateToGLSL");

     const OpenGLVersion& version = ToBackend(GetDevice())->GetGL().GetVersion();

     GLSLCompilationRequest req = {};

     auto tintProgram = GetTintProgram();
     req.inputProgram = &(tintProgram->program);

     using tint::BindingPoint;
     // Since (non-Vulkan) GLSL does not support descriptor sets, generate a
     // mapping from the original group/binding pair to a binding-only
     // value. This mapping will be used by Tint to remap all global
     // variables to the 1D space.
     const EntryPointMetadata& entryPointMetaData = GetEntryPoint(programmableStage.entryPoint);
     const BindingInfoArray& moduleBindingInfo = entryPointMetaData.bindings;
     BindingMap glBindings;
     BindingMap externalTextureExpansionMap;
     for (BindGroupIndex group : IterateBitSet(layout->GetBindGroupLayoutsMask())) {
         uint32_t groupAsInt = static_cast<uint32_t>(group);
         const BindGroupLayoutInternalBase* bgl = layout->GetBindGroupLayout(group);
         const auto& indices = layout->GetBindingIndexInfo()[group];
         const auto& groupBindingInfo = moduleBindingInfo[group];
         for (const auto& [bindingNumber, bindingInfo] : groupBindingInfo) {
             BindingIndex bindingIndex = bgl->GetBindingIndex(bindingNumber);
             GLuint shaderIndex = indices[bindingIndex];
             BindingPoint srcBindingPoint{groupAsInt, static_cast<uint32_t>(bindingNumber)};
             BindingPoint dstBindingPoint{0, shaderIndex};
             if (srcBindingPoint != dstBindingPoint) {
                 glBindings.emplace(srcBindingPoint, dstBindingPoint);
             }

             // For buffer bindings that can be sharable across stages, we need to rename them to
             // avoid GL program link failures due to block naming issues.
             if (std::holds_alternative<BufferBindingInfo>(bindingInfo.bindingInfo) &&
                 stage != SingleShaderStage::Compute) {
                 req.bufferBindingVariables.emplace_back(bindingInfo.name);
             }
         }

         for (const auto& [_, expansion] : bgl->GetExternalTextureBindingExpansionMap()) {
             uint32_t plane1Slot = indices[bgl->GetBindingIndex(expansion.plane1)];
             uint32_t paramsSlot = indices[bgl->GetBindingIndex(expansion.params)];
             BindingPoint plane0{groupAsInt, static_cast<uint32_t>(expansion.plane0)};
             BindingPoint plane1{groupAsInt, static_cast<uint32_t>(expansion.plane1)};
             BindingPoint params{groupAsInt, static_cast<uint32_t>(expansion.params)};
             glBindings.emplace(plane1, BindingPoint{0u, plane1Slot});
             glBindings.emplace(params, BindingPoint{0u, paramsSlot});
             externalTextureExpansionMap[plane0] = plane1;
         }
     }

     tint::inspector::Inspector inspector(*req.inputProgram);

     // Some texture builtin functions are unsupported on GLSL ES. These are emulated with internal
     // uniforms.
     tint::TextureBuiltinsFromUniformOptions textureBuiltinsFromUniform;
     textureBuiltinsFromUniform.ubo_binding = {kMaxBindGroups + 1, 0};

     auto textureBuiltinsFromUniformData = inspector.GetTextureQueries(programmableStage.entryPoint);
     bool needsInternalUBO = false;
     if (!textureBuiltinsFromUniformData.empty()) {
         needsInternalUBO = true;
         for (size_t i = 0; i < textureBuiltinsFromUniformData.size(); ++i) {
             const auto& info = textureBuiltinsFromUniformData[i];

             // This is the unmodified binding point from the WGSL shader.
             BindingPoint srcBindingPoint{info.group, info.binding};
             textureBuiltinsFromUniform.ubo_bindingpoint_ordering.emplace_back(srcBindingPoint);

             // The remapped binding point is inserted into the Dawn data structure.
             const BindGroupLayoutInternalBase* bgl =
                 layout->GetBindGroupLayout(BindGroupIndex{info.group});
             BindingPoint dstBindingPoint = BindingPoint{
                 info.group,
                 static_cast<uint32_t>(bgl->GetBindingIndex(BindingNumber{info.binding}))};

             BindPointFunction type = BindPointFunction::kTextureNumLevels;
             switch (info.type) {
                 case tint::inspector::Inspector::TextureQueryType::kTextureNumLevels:
                     type = BindPointFunction::kTextureNumLevels;
                     break;
                 case tint::inspector::Inspector::TextureQueryType::kTextureNumSamples:
                     type = BindPointFunction::kTextureNumSamples;
                     break;
             }

             // Note, the `sizeof(uint32_t)` has to match up with the data type created by the
             // `TextureBuiltinsFromUniform` when it creates the UBO structure.
             bindingPointToData->emplace(
                 dstBindingPoint, std::pair{type, static_cast<uint32_t>(i * sizeof(uint32_t))});
         }
     }

     // Remap the internal ubo binding as well.
     glBindings.emplace(textureBuiltinsFromUniform.ubo_binding,
                        BindingPoint{0, layout->GetInternalUniformBinding()});

     std::optional<tint::ast::transform::SubstituteOverride::Config> substituteOverrideConfig;
     if (!programmableStage.metadata->overrides.empty()) {
         substituteOverrideConfig = BuildSubstituteOverridesTransformConfig(programmableStage);
     }

     const CombinedLimits& limits = GetDevice()->GetLimits();

     req.stage = stage;
     req.entryPointName = programmableStage.entryPoint;
     req.substituteOverrideConfig = std::move(substituteOverrideConfig);
     req.limits = LimitsForCompilationRequest::Create(limits.v1);
     req.platform = UnsafeUnkeyedValue(GetDevice()->GetPlatform());

     req.tintOptions.version = tint::glsl::writer::Version(ToTintGLStandard(version.GetStandard()),
                                                           version.GetMajor(), version.GetMinor());

     req.tintOptions.disable_robustness = false;

     if (usesInstanceIndex) {
         req.tintOptions.first_instance_offset =
             4 * PipelineLayout::PushConstantLocation::FirstInstance;
     }

     if (usesFragDepth) {
         req.tintOptions.depth_range_offsets = {4 * PipelineLayout::PushConstantLocation::MinDepth,
                                                4 * PipelineLayout::PushConstantLocation::MaxDepth};
     }

     req.disableSymbolRenaming = GetDevice()->IsToggleEnabled(Toggle::DisableSymbolRenaming);

     req.interstageVariables = {};
     for (size_t i = 0; i < entryPointMetaData.interStageVariables.size(); i++) {
         if (entryPointMetaData.usedInterStageVariables[i]) {
             req.interstageVariables.emplace_back(static_cast<uint32_t>(i),
                                                  entryPointMetaData.interStageVariables[i].name);
         }
     }

     req.tintOptions.external_texture_options = BuildExternalTextureTransformBindings(layout);
     req.tintOptions.binding_remapper_options.binding_points = std::move(glBindings);
     req.tintOptions.texture_builtins_from_uniform = std::move(textureBuiltinsFromUniform);
     req.tintOptions.disable_polyfill_integer_div_mod =
         GetDevice()->IsToggleEnabled(Toggle::DisablePolyfillsOnIntegerDivisonAndModulo);

     // When textures are accessed without a sampler (e.g., textureLoad()),
     // GetSamplerTextureUses() will return this sentinel value.
     BindingPoint placeholderBindingPoint{static_cast<uint32_t>(kMaxBindGroupsTyped), 0};

     *needsPlaceholderSampler = false;
     // Find all the sampler/texture pairs for this entry point, and create
     // CombinedSamplers for them. CombinedSampler records the binding points
     // of the original texture and sampler, and generates a unique name. The
     // corresponding uniforms will be retrieved by these generated names
     // in PipelineGL. Any texture-only references will have
     // "usePlaceholderSampler" set to true, and only the texture binding point
     // will be used in naming them. In addition, Dawn will bind a
     // non-filtering sampler for them (see PipelineGL).
     auto uses =
         inspector.GetSamplerTextureUses(programmableStage.entryPoint, placeholderBindingPoint);
     CombinedSamplerInfo combinedSamplerInfo;
     for (const auto& use : uses) {
         CombinedSampler* info =
             AppendCombinedSampler(&combinedSamplerInfo, use, placeholderBindingPoint);

         if (info->usePlaceholderSampler) {
             *needsPlaceholderSampler = true;
             req.tintOptions.placeholder_binding_point = placeholderBindingPoint;
         }
         req.tintOptions.binding_map[use] = info->GetName();

         // If the texture has an associated plane1 texture (ie., it's an external texture),
         // append a new combined sampler with the same sampler and the plane1 texture.
         BindingMap::iterator plane1Texture =
             externalTextureExpansionMap.find(use.texture_binding_point);
         if (plane1Texture != externalTextureExpansionMap.end()) {
             tint::inspector::SamplerTexturePair plane1Use{use.sampler_binding_point,
                                                           plane1Texture->second};
             CombinedSampler* plane1Info =
                 AppendCombinedSampler(&combinedSamplerInfo, plane1Use, placeholderBindingPoint);
             req.tintOptions.binding_map[plane1Use] = plane1Info->GetName();
         }
     }

     CacheResult<GLSLCompilation> compilationResult;
     DAWN_TRY_LOAD_OR_RUN(
         compilationResult, GetDevice(), std::move(req), GLSLCompilation::FromBlob,
         [](GLSLCompilationRequest r) -> ResultOrError<GLSLCompilation> {
             tint::ast::transform::Manager transformManager;
             tint::ast::transform::DataMap transformInputs;

             transformManager.Add<tint::ast::transform::SingleEntryPoint>();
             transformInputs.Add<tint::ast::transform::SingleEntryPoint::Config>(r.entryPointName);

             {
                 tint::ast::transform::Renamer::Remappings assignedRenamings = {};

                 // Give explicit renaming mappings for interstage variables
                 // Because GLSL requires interstage IO names to match.
                 for (const auto& it : r.interstageVariables) {
                     assignedRenamings.emplace(
                         it.second, "dawn_interstage_location_" + std::to_string(it.first));
                 }

                 // Prepend v_ or f_ to buffer binding variable names in order to avoid collisions in
                 // renamed interface blocks. The AddBlockAttribute transform in the Tint GLSL
                 // printer will always generate wrapper structs from such bindings.
                 for (const auto& variableName : r.bufferBindingVariables) {
                     assignedRenamings.emplace(
                         variableName,
                         (r.stage == SingleShaderStage::Vertex ? "v_" : "f_") + variableName);
                 }

                 // Needs to run early so that they can use builtin names safely.
                 // TODO(dawn:2180): move this transform into Tint.
                 transformManager.Add<tint::ast::transform::Renamer>();
                 transformInputs.Add<tint::ast::transform::Renamer::Config>(
                     r.disableSymbolRenaming ? tint::ast::transform::Renamer::Target::kGlslKeywords
                                             : tint::ast::transform::Renamer::Target::kAll,
                     false, std::move(assignedRenamings));
             }

             if (r.substituteOverrideConfig) {
                 // This needs to run after SingleEntryPoint transform which removes unused overrides
                 // for current entry point.
                 transformManager.Add<tint::ast::transform::SubstituteOverride>();
                 transformInputs.Add<tint::ast::transform::SubstituteOverride::Config>(
                     std::move(r.substituteOverrideConfig).value());
             }

             tint::Program program;
             tint::ast::transform::DataMap transformOutputs;
             DAWN_TRY_ASSIGN(program, RunTransforms(&transformManager, r.inputProgram,
                                                    transformInputs, &transformOutputs, nullptr));

             // TODO(dawn:2180): refactor out.
             // Get the entry point name after the renamer pass.
             // In the case of the entry-point name being a reserved GLSL keyword
             // (including `main`) the entry-point would have been renamed
             // regardless of the `disableSymbolRenaming` flag. Always check the
             // rename map, and if the name was changed, get the new one.
             auto* data = transformOutputs.Get<tint::ast::transform::Renamer::Data>();
             DAWN_ASSERT(data != nullptr);
             auto it = data->remappings.find(r.entryPointName.data());
             std::string remappedEntryPoint;
             if (it != data->remappings.end()) {
                 remappedEntryPoint = it->second;
             } else {
                 remappedEntryPoint = r.entryPointName;
             }
             DAWN_ASSERT(remappedEntryPoint != "");

             if (r.stage == SingleShaderStage::Compute) {
                 // Validate workgroup size after program runs transforms.
                 Extent3D _;
                 DAWN_TRY_ASSIGN(_, ValidateComputeStageWorkgroupSize(
                                        program, remappedEntryPoint.c_str(), r.limits,
                                        /* fullSubgroups */ {}));
             }

             auto result = tint::glsl::writer::Generate(program, r.tintOptions, remappedEntryPoint);
             DAWN_INVALID_IF(result != tint::Success, "An error occurred while generating GLSL:\n%s",
                             result.Failure().reason.Str());

             return GLSLCompilation{{std::move(result->glsl)}};
         },
         "OpenGL.CompileShaderToGLSL");

     if (GetDevice()->IsToggleEnabled(Toggle::DumpShaders)) {
         std::ostringstream dumpedMsg;
         dumpedMsg << "/* Dumped generated GLSL */" << std::endl << compilationResult->glsl;

         GetDevice()->EmitLog(WGPULoggingType_Info, dumpedMsg.str().c_str());
     }

     GLuint shader = gl.CreateShader(GLShaderType(stage));
     const char* source = compilationResult->glsl.c_str();
     gl.ShaderSource(shader, 1, &source, nullptr);
     gl.CompileShader(shader);

     GLint compileStatus = GL_FALSE;
     gl.GetShaderiv(shader, GL_COMPILE_STATUS, &compileStatus);
     if (compileStatus == GL_FALSE) {
         GLint infoLogLength = 0;
         gl.GetShaderiv(shader, GL_INFO_LOG_LENGTH, &infoLogLength);

         if (infoLogLength > 1) {
             std::vector<char> buffer(infoLogLength);
             gl.GetShaderInfoLog(shader, infoLogLength, nullptr, &buffer[0]);
             gl.DeleteShader(shader);
             return DAWN_VALIDATION_ERROR("%s\nProgram compilation failed:\n%s", source,
                                          buffer.data());
         }
     }

     GetDevice()->GetBlobCache()->EnsureStored(compilationResult);
     *needsTextureBuiltinUniformBuffer = needsInternalUBO;

     *combinedSamplers = std::move(combinedSamplerInfo);
     return shader;
 }

 }  // namespace dawn::native::opengl
	// Copyright 2017 The Dawn & Tint Authors
	//
	// Redistribution and use in source and binary forms, with or without
	// modification, are permitted provided that the following conditions are met:
	//
	// 1. Redistributions of source code must retain the above copyright notice, this
	// list of conditions and the following disclaimer.
	//
	// 2. Redistributions in binary form must reproduce the above copyright notice,
	// this list of conditions and the following disclaimer in the documentation
	// and/or other materials provided with the distribution.
	//
	// 3. Neither the name of the copyright holder nor the names of its
	// contributors may be used to endorse or promote products derived from
	// this software without specific prior written permission.
	//
	// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
	// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
	// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
	// FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	// DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
	// SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
	// CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
	// OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
	// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

	#include "dawn/native/opengl/ShaderModuleGL.h"

	#include <sstream>
	#include <unordered_map>
	#include <utility>

	#include "dawn/native/BindGroupLayoutInternal.h"
	#include "dawn/native/CacheRequest.h"
	#include "dawn/native/Pipeline.h"
	#include "dawn/native/TintUtils.h"
	#include "dawn/native/opengl/BindingPoint.h"
	#include "dawn/native/opengl/DeviceGL.h"
	#include "dawn/native/opengl/PipelineLayoutGL.h"
	#include "dawn/platform/DawnPlatform.h"
	#include "dawn/platform/tracing/TraceEvent.h"

	#include "tint/tint.h"

	namespace dawn::native {
	namespace {

	GLenum GLShaderType(SingleShaderStage stage) {
	switch (stage) {
	case SingleShaderStage::Vertex:
	return GL_VERTEX_SHADER;
	case SingleShaderStage::Fragment:
	return GL_FRAGMENT_SHADER;
	case SingleShaderStage::Compute:
	return GL_COMPUTE_SHADER;
	}
	DAWN_UNREACHABLE();
	}

	tint::glsl::writer::Version::Standard ToTintGLStandard(opengl::OpenGLVersion::Standard standard) {
	switch (standard) {
	case opengl::OpenGLVersion::Standard::Desktop:
	return tint::glsl::writer::Version::Standard::kDesktop;
	case opengl::OpenGLVersion::Standard::ES:
	return tint::glsl::writer::Version::Standard::kES;
	}
	DAWN_UNREACHABLE();
	}

	using BindingMap = std::unordered_map<tint::BindingPoint, tint::BindingPoint>;

	opengl::CombinedSampler* AppendCombinedSampler(opengl::CombinedSamplerInfo* info,
	tint::inspector::SamplerTexturePair pair,
	tint::BindingPoint placeholderBindingPoint) {
	info->emplace_back();
	opengl::CombinedSampler* combinedSampler = &info->back();
	combinedSampler->usePlaceholderSampler = pair.sampler_binding_point == placeholderBindingPoint;
	combinedSampler->samplerLocation.group = BindGroupIndex(pair.sampler_binding_point.group);
	combinedSampler->samplerLocation.binding = BindingNumber(pair.sampler_binding_point.binding);
	combinedSampler->textureLocation.group = BindGroupIndex(pair.texture_binding_point.group);
	combinedSampler->textureLocation.binding = BindingNumber(pair.texture_binding_point.binding);
	return combinedSampler;
	}

	using InterstageLocationAndName = std::pair<uint32_t, std::string>;

	#define GLSL_COMPILATION_REQUEST_MEMBERS(X) \
	X(const tint::Program*, inputProgram) \
	X(std::string, entryPointName) \
	X(SingleShaderStage, stage) \
	X(std::optional<tint::ast::transform::SubstituteOverride::Config>, substituteOverrideConfig) \
	X(LimitsForCompilationRequest, limits) \
	X(bool, disableSymbolRenaming) \
	X(std::vector<InterstageLocationAndName>, interstageVariables) \
	X(std::vector<std::string>, bufferBindingVariables) \
	X(tint::glsl::writer::Options, tintOptions) \
	X(CacheKey::UnsafeUnkeyedValue<dawn::platform::Platform*>, platform)

	DAWN_MAKE_CACHE_REQUEST(GLSLCompilationRequest, GLSL_COMPILATION_REQUEST_MEMBERS);
	#undef GLSL_COMPILATION_REQUEST_MEMBERS

	#define GLSL_COMPILATION_MEMBERS(X) X(std::string, glsl)

	DAWN_SERIALIZABLE(struct, GLSLCompilation, GLSL_COMPILATION_MEMBERS){};
	#undef GLSL_COMPILATION_MEMBERS

	} // namespace
	} // namespace dawn::native

	namespace dawn::native::opengl {

	std::string GetBindingName(BindGroupIndex group, BindingNumber bindingNumber) {
	std::ostringstream o;
	o << "dawn_binding_" << static_cast<uint32_t>(group) << "_"
	<< static_cast<uint32_t>(bindingNumber);
	return o.str();
	}

	bool operator<(const BindingLocation& a, const BindingLocation& b) {
	return std::tie(a.group, a.binding) < std::tie(b.group, b.binding);
	}

	bool operator<(const CombinedSampler& a, const CombinedSampler& b) {
	return std::tie(a.usePlaceholderSampler, a.samplerLocation, a.textureLocation) <
	std::tie(b.usePlaceholderSampler, a.samplerLocation, b.textureLocation);
	}

	std::string CombinedSampler::GetName() const {
	std::ostringstream o;
	o << "dawn_combined";
	if (usePlaceholderSampler) {
	o << "_placeholder_sampler";
	} else {
	o << "_" << static_cast<uint32_t>(samplerLocation.group) << "_"
	<< static_cast<uint32_t>(samplerLocation.binding);
	}
	o << "_with_" << static_cast<uint32_t>(textureLocation.group) << "_"
	<< static_cast<uint32_t>(textureLocation.binding);
	return o.str();
	}

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

	ShaderModule::ShaderModule(Device* device, const UnpackedPtr<ShaderModuleDescriptor>& descriptor)
	: ShaderModuleBase(device, descriptor) {}

	MaybeError ShaderModule::Initialize(ShaderModuleParseResult* parseResult,
	OwnedCompilationMessages* compilationMessages) {
	ScopedTintICEHandler scopedICEHandler(GetDevice());

	DAWN_TRY(InitializeBase(parseResult, compilationMessages));

	return {};
	}

	ResultOrError<GLuint> ShaderModule::CompileShader(
	const OpenGLFunctions& gl,
	const ProgrammableStage& programmableStage,
	SingleShaderStage stage,
	bool usesInstanceIndex,
	bool usesFragDepth,
	CombinedSamplerInfo* combinedSamplers,
	const PipelineLayout* layout,
	bool* needsPlaceholderSampler,
	bool* needsTextureBuiltinUniformBuffer,
	BindingPointToFunctionAndOffset* bindingPointToData) const {
	TRACE_EVENT0(GetDevice()->GetPlatform(), General, "TranslateToGLSL");

	const OpenGLVersion& version = ToBackend(GetDevice())->GetGL().GetVersion();

	GLSLCompilationRequest req = {};

	auto tintProgram = GetTintProgram();
	req.inputProgram = &(tintProgram->program);

	using tint::BindingPoint;
	// Since (non-Vulkan) GLSL does not support descriptor sets, generate a
	// mapping from the original group/binding pair to a binding-only
	// value. This mapping will be used by Tint to remap all global
	// variables to the 1D space.
	const EntryPointMetadata& entryPointMetaData = GetEntryPoint(programmableStage.entryPoint);
	const BindingInfoArray& moduleBindingInfo = entryPointMetaData.bindings;
	BindingMap glBindings;
	BindingMap externalTextureExpansionMap;
	for (BindGroupIndex group : IterateBitSet(layout->GetBindGroupLayoutsMask())) {
	uint32_t groupAsInt = static_cast<uint32_t>(group);
	const BindGroupLayoutInternalBase* bgl = layout->GetBindGroupLayout(group);
	const auto& indices = layout->GetBindingIndexInfo()[group];
	const auto& groupBindingInfo = moduleBindingInfo[group];
	for (const auto& [bindingNumber, bindingInfo] : groupBindingInfo) {
	BindingIndex bindingIndex = bgl->GetBindingIndex(bindingNumber);
	GLuint shaderIndex = indices[bindingIndex];
	BindingPoint srcBindingPoint{groupAsInt, static_cast<uint32_t>(bindingNumber)};
	BindingPoint dstBindingPoint{0, shaderIndex};
	if (srcBindingPoint != dstBindingPoint) {
	glBindings.emplace(srcBindingPoint, dstBindingPoint);
	}

	// For buffer bindings that can be sharable across stages, we need to rename them to
	// avoid GL program link failures due to block naming issues.
	if (std::holds_alternative<BufferBindingInfo>(bindingInfo.bindingInfo) &&
	stage != SingleShaderStage::Compute) {
	req.bufferBindingVariables.emplace_back(bindingInfo.name);
	}
	}

	for (const auto& [_, expansion] : bgl->GetExternalTextureBindingExpansionMap()) {
	uint32_t plane1Slot = indices[bgl->GetBindingIndex(expansion.plane1)];
	uint32_t paramsSlot = indices[bgl->GetBindingIndex(expansion.params)];
	BindingPoint plane0{groupAsInt, static_cast<uint32_t>(expansion.plane0)};
	BindingPoint plane1{groupAsInt, static_cast<uint32_t>(expansion.plane1)};
	BindingPoint params{groupAsInt, static_cast<uint32_t>(expansion.params)};
	glBindings.emplace(plane1, BindingPoint{0u, plane1Slot});
	glBindings.emplace(params, BindingPoint{0u, paramsSlot});
	externalTextureExpansionMap[plane0] = plane1;
	}
	}

	tint::inspector::Inspector inspector(*req.inputProgram);

	// Some texture builtin functions are unsupported on GLSL ES. These are emulated with internal
	// uniforms.
	tint::TextureBuiltinsFromUniformOptions textureBuiltinsFromUniform;
	textureBuiltinsFromUniform.ubo_binding = {kMaxBindGroups + 1, 0};

	auto textureBuiltinsFromUniformData = inspector.GetTextureQueries(programmableStage.entryPoint);
	bool needsInternalUBO = false;
	if (!textureBuiltinsFromUniformData.empty()) {
	needsInternalUBO = true;
	for (size_t i = 0; i < textureBuiltinsFromUniformData.size(); ++i) {
	const auto& info = textureBuiltinsFromUniformData[i];

	// This is the unmodified binding point from the WGSL shader.
	BindingPoint srcBindingPoint{info.group, info.binding};
	textureBuiltinsFromUniform.ubo_bindingpoint_ordering.emplace_back(srcBindingPoint);

	// The remapped binding point is inserted into the Dawn data structure.
	const BindGroupLayoutInternalBase* bgl =
	layout->GetBindGroupLayout(BindGroupIndex{info.group});
	BindingPoint dstBindingPoint = BindingPoint{
	info.group,
	static_cast<uint32_t>(bgl->GetBindingIndex(BindingNumber{info.binding}))};

	BindPointFunction type = BindPointFunction::kTextureNumLevels;
	switch (info.type) {
	case tint::inspector::Inspector::TextureQueryType::kTextureNumLevels:
	type = BindPointFunction::kTextureNumLevels;
	break;
	case tint::inspector::Inspector::TextureQueryType::kTextureNumSamples:
	type = BindPointFunction::kTextureNumSamples;
	break;
	}

	// Note, the `sizeof(uint32_t)` has to match up with the data type created by the
	// `TextureBuiltinsFromUniform` when it creates the UBO structure.
	bindingPointToData->emplace(
	dstBindingPoint, std::pair{type, static_cast<uint32_t>(i * sizeof(uint32_t))});
	}
	}

	// Remap the internal ubo binding as well.
	glBindings.emplace(textureBuiltinsFromUniform.ubo_binding,
	BindingPoint{0, layout->GetInternalUniformBinding()});

	std::optional<tint::ast::transform::SubstituteOverride::Config> substituteOverrideConfig;
	if (!programmableStage.metadata->overrides.empty()) {
	substituteOverrideConfig = BuildSubstituteOverridesTransformConfig(programmableStage);
	}

	const CombinedLimits& limits = GetDevice()->GetLimits();

	req.stage = stage;
	req.entryPointName = programmableStage.entryPoint;
	req.substituteOverrideConfig = std::move(substituteOverrideConfig);
	req.limits = LimitsForCompilationRequest::Create(limits.v1);
	req.platform = UnsafeUnkeyedValue(GetDevice()->GetPlatform());

	req.tintOptions.version = tint::glsl::writer::Version(ToTintGLStandard(version.GetStandard()),
	version.GetMajor(), version.GetMinor());

	req.tintOptions.disable_robustness = false;

	if (usesInstanceIndex) {
	req.tintOptions.first_instance_offset =
	4 * PipelineLayout::PushConstantLocation::FirstInstance;
	}

	if (usesFragDepth) {
	req.tintOptions.depth_range_offsets = {4 * PipelineLayout::PushConstantLocation::MinDepth,
	4 * PipelineLayout::PushConstantLocation::MaxDepth};
	}

	req.disableSymbolRenaming = GetDevice()->IsToggleEnabled(Toggle::DisableSymbolRenaming);

	req.interstageVariables = {};
	for (size_t i = 0; i < entryPointMetaData.interStageVariables.size(); i++) {
	if (entryPointMetaData.usedInterStageVariables[i]) {
	req.interstageVariables.emplace_back(static_cast<uint32_t>(i),
	entryPointMetaData.interStageVariables[i].name);
	}
	}

	req.tintOptions.external_texture_options = BuildExternalTextureTransformBindings(layout);
	req.tintOptions.binding_remapper_options.binding_points = std::move(glBindings);
	req.tintOptions.texture_builtins_from_uniform = std::move(textureBuiltinsFromUniform);
	req.tintOptions.disable_polyfill_integer_div_mod =
	GetDevice()->IsToggleEnabled(Toggle::DisablePolyfillsOnIntegerDivisonAndModulo);

	// When textures are accessed without a sampler (e.g., textureLoad()),
	// GetSamplerTextureUses() will return this sentinel value.
	BindingPoint placeholderBindingPoint{static_cast<uint32_t>(kMaxBindGroupsTyped), 0};

	*needsPlaceholderSampler = false;
	// Find all the sampler/texture pairs for this entry point, and create
	// CombinedSamplers for them. CombinedSampler records the binding points
	// of the original texture and sampler, and generates a unique name. The
	// corresponding uniforms will be retrieved by these generated names
	// in PipelineGL. Any texture-only references will have
	// "usePlaceholderSampler" set to true, and only the texture binding point
	// will be used in naming them. In addition, Dawn will bind a
	// non-filtering sampler for them (see PipelineGL).
	auto uses =
	inspector.GetSamplerTextureUses(programmableStage.entryPoint, placeholderBindingPoint);
	CombinedSamplerInfo combinedSamplerInfo;
	for (const auto& use : uses) {
	CombinedSampler* info =
	AppendCombinedSampler(&combinedSamplerInfo, use, placeholderBindingPoint);

	if (info->usePlaceholderSampler) {
	*needsPlaceholderSampler = true;
	req.tintOptions.placeholder_binding_point = placeholderBindingPoint;
	}
	req.tintOptions.binding_map[use] = info->GetName();

	// If the texture has an associated plane1 texture (ie., it's an external texture),
	// append a new combined sampler with the same sampler and the plane1 texture.
	BindingMap::iterator plane1Texture =
	externalTextureExpansionMap.find(use.texture_binding_point);
	if (plane1Texture != externalTextureExpansionMap.end()) {
	tint::inspector::SamplerTexturePair plane1Use{use.sampler_binding_point,
	plane1Texture->second};
	CombinedSampler* plane1Info =
	AppendCombinedSampler(&combinedSamplerInfo, plane1Use, placeholderBindingPoint);
	req.tintOptions.binding_map[plane1Use] = plane1Info->GetName();
	}
	}

	CacheResult<GLSLCompilation> compilationResult;
	DAWN_TRY_LOAD_OR_RUN(
	compilationResult, GetDevice(), std::move(req), GLSLCompilation::FromBlob,
	[](GLSLCompilationRequest r) -> ResultOrError<GLSLCompilation> {
	tint::ast::transform::Manager transformManager;
	tint::ast::transform::DataMap transformInputs;

	transformManager.Add<tint::ast::transform::SingleEntryPoint>();
	transformInputs.Add<tint::ast::transform::SingleEntryPoint::Config>(r.entryPointName);

	{
	tint::ast::transform::Renamer::Remappings assignedRenamings = {};

	// Give explicit renaming mappings for interstage variables
	// Because GLSL requires interstage IO names to match.
	for (const auto& it : r.interstageVariables) {
	assignedRenamings.emplace(
	it.second, "dawn_interstage_location_" + std::to_string(it.first));
	}

	// Prepend v_ or f_ to buffer binding variable names in order to avoid collisions in
	// renamed interface blocks. The AddBlockAttribute transform in the Tint GLSL
	// printer will always generate wrapper structs from such bindings.
	for (const auto& variableName : r.bufferBindingVariables) {
	assignedRenamings.emplace(
	variableName,
	(r.stage == SingleShaderStage::Vertex ? "v_" : "f_") + variableName);
	}

	// Needs to run early so that they can use builtin names safely.
	// TODO(dawn:2180): move this transform into Tint.
	transformManager.Add<tint::ast::transform::Renamer>();
	transformInputs.Add<tint::ast::transform::Renamer::Config>(
	r.disableSymbolRenaming ? tint::ast::transform::Renamer::Target::kGlslKeywords
	: tint::ast::transform::Renamer::Target::kAll,
	false, std::move(assignedRenamings));
	}

	if (r.substituteOverrideConfig) {
	// This needs to run after SingleEntryPoint transform which removes unused overrides
	// for current entry point.
	transformManager.Add<tint::ast::transform::SubstituteOverride>();
	transformInputs.Add<tint::ast::transform::SubstituteOverride::Config>(
	std::move(r.substituteOverrideConfig).value());
	}

	tint::Program program;
	tint::ast::transform::DataMap transformOutputs;
	DAWN_TRY_ASSIGN(program, RunTransforms(&transformManager, r.inputProgram,
	transformInputs, &transformOutputs, nullptr));

	// TODO(dawn:2180): refactor out.
	// Get the entry point name after the renamer pass.
	// In the case of the entry-point name being a reserved GLSL keyword
	// (including `main`) the entry-point would have been renamed
	// regardless of the `disableSymbolRenaming` flag. Always check the
	// rename map, and if the name was changed, get the new one.
	auto* data = transformOutputs.Get<tint::ast::transform::Renamer::Data>();
	DAWN_ASSERT(data != nullptr);
	auto it = data->remappings.find(r.entryPointName.data());
	std::string remappedEntryPoint;
	if (it != data->remappings.end()) {
	remappedEntryPoint = it->second;
	} else {
	remappedEntryPoint = r.entryPointName;
	}
	DAWN_ASSERT(remappedEntryPoint != "");

	if (r.stage == SingleShaderStage::Compute) {
	// Validate workgroup size after program runs transforms.
	Extent3D _;
	DAWN_TRY_ASSIGN(_, ValidateComputeStageWorkgroupSize(
	program, remappedEntryPoint.c_str(), r.limits,
	/* fullSubgroups */ {}));
	}

	auto result = tint::glsl::writer::Generate(program, r.tintOptions, remappedEntryPoint);
	DAWN_INVALID_IF(result != tint::Success, "An error occurred while generating GLSL:\n%s",
	result.Failure().reason.Str());

	return GLSLCompilation{{std::move(result->glsl)}};
	},
	"OpenGL.CompileShaderToGLSL");

	if (GetDevice()->IsToggleEnabled(Toggle::DumpShaders)) {
	std::ostringstream dumpedMsg;
	dumpedMsg << "/* Dumped generated GLSL */" << std::endl << compilationResult->glsl;

	GetDevice()->EmitLog(WGPULoggingType_Info, dumpedMsg.str().c_str());
	}

	GLuint shader = gl.CreateShader(GLShaderType(stage));
	const char* source = compilationResult->glsl.c_str();
	gl.ShaderSource(shader, 1, &source, nullptr);
	gl.CompileShader(shader);

	GLint compileStatus = GL_FALSE;
	gl.GetShaderiv(shader, GL_COMPILE_STATUS, &compileStatus);
	if (compileStatus == GL_FALSE) {
	GLint infoLogLength = 0;
	gl.GetShaderiv(shader, GL_INFO_LOG_LENGTH, &infoLogLength);

	if (infoLogLength > 1) {
	std::vector<char> buffer(infoLogLength);
	gl.GetShaderInfoLog(shader, infoLogLength, nullptr, &buffer[0]);
	gl.DeleteShader(shader);
	return DAWN_VALIDATION_ERROR("%s\nProgram compilation failed:\n%s", source,
	buffer.data());
	}
	}

	GetDevice()->GetBlobCache()->EnsureStored(compilationResult);
	*needsTextureBuiltinUniformBuffer = needsInternalUBO;

	*combinedSamplers = std::move(combinedSamplerInfo);
	return shader;
	}

	} // namespace dawn::native::opengl