Quelle  Program.cpp   Sprache: C

//
// Copyright 2002 The ANGLE Project Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
//

// Program.cpp: Implements the gl::Program class. Implements GL program objects
// and related functionality. [OpenGL ES 2.0.24] section 2.10.3 page 28.

#include "libANGLE/Program.h"

#include <algorithm>
#include <utility>

#include "common/angle_version_info.h"
#include "common/bitset_utils.h"
#include "common/debug.h"
#include "common/platform.h"
#include "common/string_utils.h"
#include "common/utilities.h"
#include "compiler/translator/blocklayout.h"
#include "libANGLE/Context.h"
#include "libANGLE/ErrorStrings.h"
#include "libANGLE/MemoryProgramCache.h"
#include "libANGLE/ProgramLinkedResources.h"
#include "libANGLE/ResourceManager.h"
#include "libANGLE/Uniform.h"
#include "libANGLE/VaryingPacking.h"
#include "libANGLE/Version.h"
#include "libANGLE/capture/FrameCapture.h"
#include "libANGLE/features.h"
#include "libANGLE/histogram_macros.h"
#include "libANGLE/queryconversions.h"
#include "libANGLE/renderer/GLImplFactory.h"
#include "libANGLE/renderer/ProgramImpl.h"
#include "platform/FrontendFeatures_autogen.h"
#include "platform/PlatformMethods.h"

namespace gl
{

namespace
{

// This simplified cast function doesn't need to worry about advanced concepts like
// depth range values, or casting to bool.
template <typename DestT, typename SrcT>
DestT UniformStateQueryCast(SrcT value);

// From-Float-To-Integer Casts
template <>
GLint UniformStateQueryCast(GLfloat value)
{
    return clampCast<GLint>(roundf(value));
}

template <>
GLuint UniformStateQueryCast(GLfloat value)
{
    return clampCast<GLuint>(roundf(value));
}

// From-Integer-to-Integer Casts
template <>
GLint UniformStateQueryCast(GLuint value)
{
    return clampCast<GLint>(value);
}

template <>
GLuint UniformStateQueryCast(GLint value)
{
    return clampCast<GLuint>(value);
}

// From-Boolean-to-Anything Casts
template <>
GLfloat UniformStateQueryCast(GLboolean value)
{
    return (ConvertToBool(value) ? 1.0f : 0.0f);
}

template <>
GLint UniformStateQueryCast(GLboolean value)
{
    return (ConvertToBool(value) ? 1 : 0);
}

template <>
GLuint UniformStateQueryCast(GLboolean value)
{
    return (ConvertToBool(value) ? 1u : 0u);
}

// Default to static_cast
template <typename DestT, typename SrcT>
DestT UniformStateQueryCast(SrcT value)
{
    return static_cast<DestT>(value);
}

template <typename SrcT, typename DestT>
void UniformStateQueryCastLoop(DestT *dataOut, const uint8_t *srcPointer, int components)
{
    for (int comp = 0; comp < components; ++comp)
    {
        // We only work with strides of 4 bytes for uniform components. (GLfloat/GLint)
        // Don't use SrcT stride directly since GLboolean has a stride of 1 byte.
        size_t offset               = comp * 4;
        const SrcT *typedSrcPointer = reinterpret_cast<const SrcT *>(&srcPointer[offset]);
        dataOut[comp]               = UniformStateQueryCast<DestT>(*typedSrcPointer);
    }
}

template <typename VarT>
GLuint GetResourceIndexFromName(const std::vector<VarT> &list, const std::string &name)
{
    std::string nameAsArrayName = name + "[0]";
    for (size_t index = 0; index < list.size(); index++)
    {
        const VarT &resource = list[index];
        if (resource.name == name || (resource.isArray() && resource.name == nameAsArrayName))
        {
            return static_cast<GLuint>(index);
        }
    }

    return GL_INVALID_INDEX;
}

GLint GetVariableLocation(const std::vector<sh::ShaderVariable> &list,
                          const std::vector<VariableLocation> &locationList,
                          const std::string &name)
{
    size_t nameLengthWithoutArrayIndex;
    unsigned int arrayIndex = ParseArrayIndex(name, &nameLengthWithoutArrayIndex);

    for (size_t location = 0u; location < locationList.size(); ++location)
    {
        const VariableLocation &variableLocation = locationList[location];
        if (!variableLocation.used())
        {
            continue;
        }

        const sh::ShaderVariable &variable = list[variableLocation.index];

        // Array output variables may be bound out of order, so we need to ensure we only pick the
        // first element if given the base name.
        if ((variable.name == name) && (variableLocation.arrayIndex == 0))
        {
            return static_cast<GLint>(location);
        }
        if (variable.isArray() && variableLocation.arrayIndex == arrayIndex &&
            angle::BeginsWith(variable.name, name, nameLengthWithoutArrayIndex))
        {
            return static_cast<GLint>(location);
        }
    }

    return -1;
}

GLint GetVariableLocation(const std::vector<LinkedUniform> &list,
                          const std::vector<VariableLocation> &locationList,
                          const std::string &name)
{
    size_t nameLengthWithoutArrayIndex;
    unsigned int arrayIndex = ParseArrayIndex(name, &nameLengthWithoutArrayIndex);

    for (size_t location = 0u; location < locationList.size(); ++location)
    {
        const VariableLocation &variableLocation = locationList[location];
        if (!variableLocation.used())
        {
            continue;
        }

        const LinkedUniform &variable = list[variableLocation.index];

        // Array output variables may be bound out of order, so we need to ensure we only pick the
        // first element if given the base name. Uniforms don't allow this behavior and some code
        // seemingly depends on the opposite behavior, so only enable it for output variables.
        if (angle::BeginsWith(variable.name, name) && (variableLocation.arrayIndex == 0))
        {
            if (name.length() == variable.name.length())
            {
                ASSERT(name == variable.name);
                // GLES 3.1 November 2016 page 87.
                // The string exactly matches the name of the active variable.
                return static_cast<GLint>(location);
            }
            if (name.length() + 3u == variable.name.length() && variable.isArray())
            {
                ASSERT(name + "[0]" == variable.name);
                // The string identifies the base name of an active array, where the string would
                // exactly match the name of the variable if the suffix "[0]" were appended to the
                // string.
                return static_cast<GLint>(location);
            }
        }
        if (variable.isArray() && variableLocation.arrayIndex == arrayIndex &&
            nameLengthWithoutArrayIndex + 3u == variable.name.length() &&
            angle::BeginsWith(variable.name, name, nameLengthWithoutArrayIndex))
        {
            ASSERT(name.substr(0u, nameLengthWithoutArrayIndex) + "[0]" == variable.name);
            // The string identifies an active element of the array, where the string ends with the
            // concatenation of the "[" character, an integer (with no "+" sign, extra leading
            // zeroes, or whitespace) identifying an array element, and the "]" character, the
            // integer is less than the number of active elements of the array variable, and where
            // the string would exactly match the enumerated name of the array if the decimal
            // integer were replaced with zero.
            return static_cast<GLint>(location);
        }
    }

    return -1;
}

void CopyStringToBuffer(GLchar *buffer,
                        const std::string &string,
                        GLsizei bufSize,
                        GLsizei *lengthOut)
{
    ASSERT(bufSize > 0);
    size_t length = std::min<size_t>(bufSize - 1, string.length());
    memcpy(buffer, string.c_str(), length);
    buffer[length] = '\0';

    if (lengthOut)
    {
        *lengthOut = static_cast<GLsizei>(length);
    }
}

GLuint GetInterfaceBlockIndex(const std::vector<InterfaceBlock> &list, const std::string &name)
{
    std::vector<unsigned int> subscripts;
    std::string baseName = ParseResourceName(name, &subscripts);

    unsigned int numBlocks = static_cast<unsigned int>(list.size());
    for (unsigned int blockIndex = 0; blockIndex < numBlocks; blockIndex++)
    {
        const auto &block = list[blockIndex];
        if (block.name == baseName)
        {
            const bool arrayElementZero =
                (subscripts.empty() && (!block.isArray || block.arrayElement == 0));
            const bool arrayElementMatches =
                (subscripts.size() == 1 && subscripts[0] == block.arrayElement);
            if (arrayElementMatches || arrayElementZero)
            {
                return blockIndex;
            }
        }
    }

    return GL_INVALID_INDEX;
}

void GetInterfaceBlockName(const UniformBlockIndex index,
                           const std::vector<InterfaceBlock> &list,
                           GLsizei bufSize,
                           GLsizei *length,
                           GLchar *name)
{
    ASSERT(index.value < list.size());

    const auto &block = list[index.value];

    if (bufSize > 0)
    {
        std::string blockName = block.name;

        if (block.isArray)
        {
            blockName += ArrayString(block.arrayElement);
        }
        CopyStringToBuffer(name, blockName, bufSize, length);
    }
}

void InitUniformBlockLinker(const Context *context,
                            const ProgramState &state,
                            UniformBlockLinker *blockLinker)
{
    for (ShaderType shaderType : AllShaderTypes())
    {
        Shader *shader = state.getAttachedShader(shaderType);
        if (shader)
        {
            blockLinker->addShaderBlocks(shaderType, &shader->getUniformBlocks(context));
        }
    }
}

void InitShaderStorageBlockLinker(const Context *context,
                                  const ProgramState &state,
                                  ShaderStorageBlockLinker *blockLinker)
{
    for (ShaderType shaderType : AllShaderTypes())
    {
        Shader *shader = state.getAttachedShader(shaderType);
        if (shader != nullptr)
        {
            blockLinker->addShaderBlocks(shaderType, &shader->getShaderStorageBlocks(context));
        }
    }
}
}  // anonymous namespace

const char *GetLinkMismatchErrorString(LinkMismatchError linkError)
{
    switch (linkError)
    {
        case LinkMismatchError::TYPE_MISMATCH:
            return "Type";
        case LinkMismatchError::ARRAYNESS_MISMATCH:
            return "Array-ness";
        case LinkMismatchError::ARRAY_SIZE_MISMATCH:
            return "Array size";
        case LinkMismatchError::PRECISION_MISMATCH:
            return "Precision";
        case LinkMismatchError::STRUCT_NAME_MISMATCH:
            return "Structure name";
        case LinkMismatchError::FIELD_NUMBER_MISMATCH:
            return "Field number";
        case LinkMismatchError::FIELD_NAME_MISMATCH:
            return "Field name";

        case LinkMismatchError::INTERPOLATION_TYPE_MISMATCH:
            return "Interpolation type";
        case LinkMismatchError::INVARIANCE_MISMATCH:
            return "Invariance";

        case LinkMismatchError::BINDING_MISMATCH:
            return "Binding layout qualifier";
        case LinkMismatchError::LOCATION_MISMATCH:
            return "Location layout qualifier";
        case LinkMismatchError::OFFSET_MISMATCH:
            return "Offset layout qualifier";
        case LinkMismatchError::INSTANCE_NAME_MISMATCH:
            return "Instance name qualifier";
        case LinkMismatchError::FORMAT_MISMATCH:
            return "Format qualifier";

        case LinkMismatchError::LAYOUT_QUALIFIER_MISMATCH:
            return "Layout qualifier";
        case LinkMismatchError::MATRIX_PACKING_MISMATCH:
            return "Matrix Packing";

        case LinkMismatchError::FIELD_LOCATION_MISMATCH:
            return "Field location";
        case LinkMismatchError::FIELD_STRUCT_NAME_MISMATCH:
            return "Field structure name";
        default:
            UNREACHABLE();
            return "";
    }
}

void UpdateInterfaceVariable(std::vector<sh::ShaderVariable> *block, const sh::ShaderVariable &var)
{
    if (!var.isStruct())
    {
        block->emplace_back(var);
        block->back().resetEffectiveLocation();
    }

    for (const sh::ShaderVariable &field : var.fields)
    {
        ASSERT(!var.name.empty() || var.isShaderIOBlock);

        // Shader I/O block naming is similar to UBOs and SSBOs:
        //
        //     in Block
        //     {
        //         type field;  // produces "field"
        //     };
        //
        //     in Block2
        //     {
        //         type field;  // produces "Block2.field"
        //     } block2;
        //
        const std::string &baseName = var.isShaderIOBlock ? var.structOrBlockName : var.name;
        const std::string prefix    = var.name.empty() ? "" : baseName + ".";

        if (!field.isStruct())
        {
            sh::ShaderVariable fieldCopy = field;
            fieldCopy.updateEffectiveLocation(var);
            fieldCopy.name = prefix + field.name;
            block->emplace_back(fieldCopy);
        }

        for (const sh::ShaderVariable &nested : field.fields)
        {
            sh::ShaderVariable nestedCopy = nested;
            nestedCopy.updateEffectiveLocation(field);
            nestedCopy.name = prefix + field.name + "." + nested.name;
            block->emplace_back(nestedCopy);
        }
    }
}

void WriteShaderVariableBuffer(BinaryOutputStream *stream, const ShaderVariableBuffer &var)
{
    stream->writeInt(var.binding);
    stream->writeInt(var.dataSize);

    for (ShaderType shaderType : AllShaderTypes())
    {
        stream->writeBool(var.isActive(shaderType));
    }

    stream->writeInt(var.memberIndexes.size());
    for (unsigned int memberCounterIndex : var.memberIndexes)
    {
        stream->writeInt(memberCounterIndex);
    }
}

void LoadShaderVariableBuffer(BinaryInputStream *stream, ShaderVariableBuffer *var)
{
    var->binding  = stream->readInt<int>();
    var->dataSize = stream->readInt<unsigned int>();

    for (ShaderType shaderType : AllShaderTypes())
    {
        var->setActive(shaderType, stream->readBool());
    }

    size_t numMembers = stream->readInt<size_t>();
    for (size_t blockMemberIndex = 0; blockMemberIndex < numMembers; blockMemberIndex++)
    {
        var->memberIndexes.push_back(stream->readInt<unsigned int>());
    }
}

void WriteBufferVariable(BinaryOutputStream *stream, const BufferVariable &var)
{
    WriteShaderVar(stream, var);

    stream->writeInt(var.bufferIndex);
    WriteBlockMemberInfo(stream, var.blockInfo);
    stream->writeInt(var.topLevelArraySize);

    for (ShaderType shaderType : AllShaderTypes())
    {
        stream->writeBool(var.isActive(shaderType));
    }
}

void LoadBufferVariable(BinaryInputStream *stream, BufferVariable *var)
{
    LoadShaderVar(stream, var);

    var->bufferIndex = stream->readInt<int>();
    LoadBlockMemberInfo(stream, &var->blockInfo);
    var->topLevelArraySize = stream->readInt<int>();

    for (ShaderType shaderType : AllShaderTypes())
    {
        var->setActive(shaderType, stream->readBool());
    }
}

void WriteInterfaceBlock(BinaryOutputStream *stream, const InterfaceBlock &block)
{
    stream->writeString(block.name);
    stream->writeString(block.mappedName);
    stream->writeBool(block.isArray);
    stream->writeInt(block.arrayElement);

    WriteShaderVariableBuffer(stream, block);
}

void LoadInterfaceBlock(BinaryInputStream *stream, InterfaceBlock *block)
{
    block->name         = stream->readString();
    block->mappedName   = stream->readString();
    block->isArray      = stream->readBool();
    block->arrayElement = stream->readInt<unsigned int>();

    LoadShaderVariableBuffer(stream, block);
}

void WriteShInterfaceBlock(BinaryOutputStream *stream, const sh::InterfaceBlock &block)
{
    stream->writeString(block.name);
    stream->writeString(block.mappedName);
    stream->writeString(block.instanceName);
    stream->writeInt(block.arraySize);
    stream->writeEnum(block.layout);
    stream->writeBool(block.isRowMajorLayout);
    stream->writeInt(block.binding);
    stream->writeBool(block.staticUse);
    stream->writeBool(block.active);
    stream->writeEnum(block.blockType);

    stream->writeInt<size_t>(block.fields.size());
    for (const sh::ShaderVariable &shaderVariable : block.fields)
    {
        WriteShaderVar(stream, shaderVariable);
    }
}

void LoadShInterfaceBlock(BinaryInputStream *stream, sh::InterfaceBlock *block)
{
    block->name             = stream->readString();
    block->mappedName       = stream->readString();
    block->instanceName     = stream->readString();
    block->arraySize        = stream->readInt<unsigned int>();
    block->layout           = stream->readEnum<sh::BlockLayoutType>();
    block->isRowMajorLayout = stream->readBool();
    block->binding          = stream->readInt<int>();
    block->staticUse        = stream->readBool();
    block->active           = stream->readBool();
    block->blockType        = stream->readEnum<sh::BlockType>();

    block->fields.resize(stream->readInt<size_t>());
    for (sh::ShaderVariable &variable : block->fields)
    {
        LoadShaderVar(stream, &variable);
    }
}

// Saves the linking context for later use in resolveLink().
struct Program::LinkingState
{
    std::shared_ptr<ProgramExecutable> linkedExecutable;
    ProgramLinkedResources resources;
    egl::BlobCache::Key programHash;
    std::unique_ptr<rx::LinkEvent> linkEvent;
    bool linkingFromBinary;
};

const char *const g_fakepath = "C:\\fakepath";

// InfoLog implementation.
InfoLog::InfoLog() : mLazyStream(nullptr) {}

InfoLog::~InfoLog() {}

size_t InfoLog::getLength() const
{
    if (!mLazyStream)
    {
        return 0;
    }

    const std::string &logString = mLazyStream->str();
    return logString.empty() ? 0 : logString.length() + 1;
}

void InfoLog::getLog(GLsizei bufSize, GLsizei *length, char *infoLog) const
{
    size_t index = 0;

    if (bufSize > 0)
    {
        const std::string logString(str());

        if (!logString.empty())
        {
            index = std::min(static_cast<size_t>(bufSize) - 1, logString.length());
            memcpy(infoLog, logString.c_str(), index);
        }

        infoLog[index] = '\0';
    }

    if (length)
    {
        *length = static_cast<GLsizei>(index);
    }
}

// append a sanitized message to the program info log.
// The D3D compiler includes a fake file path in some of the warning or error
// messages, so lets remove all occurrences of this fake file path from the log.
void InfoLog::appendSanitized(const char *message)
{
    ensureInitialized();

    std::string msg(message);

    size_t found;
    do
    {
        found = msg.find(g_fakepath);
        if (found != std::string::npos)
        {
            msg.erase(found, strlen(g_fakepath));
        }
    } while (found != std::string::npos);

    if (!msg.empty())
    {
        *mLazyStream << message << std::endl;
    }
}

void InfoLog::reset()
{
    if (mLazyStream)
    {
        mLazyStream.reset(nullptr);
    }
}

bool InfoLog::empty() const
{
    if (!mLazyStream)
    {
        return true;
    }

    return mLazyStream->rdbuf()->in_avail() == 0;
}

void LogLinkMismatch(InfoLog &infoLog,
                     const std::string &variableName,
                     const char *variableType,
                     LinkMismatchError linkError,
                     const std::string &mismatchedStructOrBlockFieldName,
                     ShaderType shaderType1,
                     ShaderType shaderType2)
{
    std::ostringstream stream;
    stream << GetLinkMismatchErrorString(linkError) << "s of " << variableType << " '"
           << variableName;

    if (!mismatchedStructOrBlockFieldName.empty())
    {
        stream << "' member '" << variableName << "." << mismatchedStructOrBlockFieldName;
    }

    stream << "' differ between " << GetShaderTypeString(shaderType1) << " and "
           << GetShaderTypeString(shaderType2) << " shaders.";

    infoLog << stream.str();
}

bool IsActiveInterfaceBlock(const sh::InterfaceBlock &interfaceBlock)
{
    // Only 'packed' blocks are allowed to be considered inactive.
    return interfaceBlock.active || interfaceBlock.layout != sh::BLOCKLAYOUT_PACKED;
}

void WriteBlockMemberInfo(BinaryOutputStream *stream, const sh::BlockMemberInfo &var)
{
    stream->writeInt(var.arrayStride);
    stream->writeBool(var.isRowMajorMatrix);
    stream->writeInt(var.matrixStride);
    stream->writeInt(var.offset);
    stream->writeInt(var.topLevelArrayStride);
}

void LoadBlockMemberInfo(BinaryInputStream *stream, sh::BlockMemberInfo *var)
{
    var->arrayStride         = stream->readInt<int>();
    var->isRowMajorMatrix    = stream->readBool();
    var->matrixStride        = stream->readInt<int>();
    var->offset              = stream->readInt<int>();
    var->topLevelArrayStride = stream->readInt<int>();
}

void WriteShaderVar(BinaryOutputStream *stream, const sh::ShaderVariable &var)
{
    stream->writeInt(var.type);
    stream->writeInt(var.precision);
    stream->writeString(var.name);
    stream->writeString(var.mappedName);
    stream->writeIntVector(var.arraySizes);
    stream->writeBool(var.staticUse);
    stream->writeBool(var.active);
    stream->writeInt<size_t>(var.fields.size());
    for (const sh::ShaderVariable &shaderVariable : var.fields)
    {
        WriteShaderVar(stream, shaderVariable);
    }
    stream->writeString(var.structOrBlockName);
    stream->writeString(var.mappedStructOrBlockName);
    stream->writeBool(var.isRowMajorLayout);
    stream->writeInt(var.location);
    stream->writeBool(var.hasImplicitLocation);
    stream->writeInt(var.binding);
    stream->writeInt(var.imageUnitFormat);
    stream->writeInt(var.offset);
    stream->writeBool(var.rasterOrdered);
    stream->writeBool(var.readonly);
    stream->writeBool(var.writeonly);
    stream->writeBool(var.isFragmentInOut);
    stream->writeInt(var.index);
    stream->writeBool(var.yuv);
    stream->writeEnum(var.interpolation);
    stream->writeBool(var.isInvariant);
    stream->writeBool(var.isShaderIOBlock);
    stream->writeBool(var.isPatch);
    stream->writeBool(var.texelFetchStaticUse);
    stream->writeInt(var.getFlattenedOffsetInParentArrays());
}

void LoadShaderVar(gl::BinaryInputStream *stream, sh::ShaderVariable *var)
{
    var->type      = stream->readInt<GLenum>();
    var->precision = stream->readInt<GLenum>();
    stream->readString(&var->name);
    stream->readString(&var->mappedName);
    stream->readIntVector<unsigned int>(&var->arraySizes);
    var->staticUse      = stream->readBool();
    var->active         = stream->readBool();
    size_t elementCount = stream->readInt<size_t>();
    var->fields.resize(elementCount);
    for (sh::ShaderVariable &variable : var->fields)
    {
        LoadShaderVar(stream, &variable);
    }
    stream->readString(&var->structOrBlockName);
    stream->readString(&var->mappedStructOrBlockName);
    var->isRowMajorLayout    = stream->readBool();
    var->location            = stream->readInt<int>();
    var->hasImplicitLocation = stream->readBool();
    var->binding             = stream->readInt<int>();
    var->imageUnitFormat     = stream->readInt<GLenum>();
    var->offset              = stream->readInt<int>();
    var->rasterOrdered       = stream->readBool();
    var->readonly            = stream->readBool();
    var->writeonly           = stream->readBool();
    var->isFragmentInOut     = stream->readBool();
    var->index               = stream->readInt<int>();
    var->yuv                 = stream->readBool();
    var->interpolation       = stream->readEnum<sh::InterpolationType>();
    var->isInvariant         = stream->readBool();
    var->isShaderIOBlock     = stream->readBool();
    var->isPatch             = stream->readBool();
    var->texelFetchStaticUse = stream->readBool();
    var->setParentArrayIndex(stream->readInt<int>());
}

// VariableLocation implementation.
VariableLocation::VariableLocation() : arrayIndex(0), index(kUnused), ignored(false) {}

VariableLocation::VariableLocation(unsigned int arrayIndex, unsigned int index)
    : arrayIndex(arrayIndex), index(index), ignored(false)
{
    ASSERT(arrayIndex != GL_INVALID_INDEX);
}

// SamplerBindings implementation.
SamplerBinding::SamplerBinding(TextureType textureTypeIn,
                               GLenum samplerTypeIn,
                               SamplerFormat formatIn,
                               size_t elementCount)
    : textureType(textureTypeIn),
      samplerType(samplerTypeIn),
      format(formatIn),
      boundTextureUnits(elementCount, 0)
{}

SamplerBinding::SamplerBinding(const SamplerBinding &other) = default;

SamplerBinding::~SamplerBinding() = default;

// ProgramBindings implementation.
ProgramBindings::ProgramBindings() {}

ProgramBindings::~ProgramBindings() {}

void ProgramBindings::bindLocation(GLuint index, const std::string &name)
{
    mBindings[name] = index;
}

int ProgramBindings::getBindingByName(const std::string &name) const
{
    auto iter = mBindings.find(name);
    return (iter != mBindings.end()) ? iter->second : -1;
}

int ProgramBindings::getBinding(const sh::ShaderVariable &variable) const
{
    return getBindingByName(variable.name);
}

ProgramBindings::const_iterator ProgramBindings::begin() const
{
    return mBindings.begin();
}

ProgramBindings::const_iterator ProgramBindings::end() const
{
    return mBindings.end();
}

std::map<std::string, GLuint> ProgramBindings::getStableIterationMap() const
{
    return std::map<std::string, GLuint>(mBindings.begin(), mBindings.end());
}

// ProgramAliasedBindings implementation.
ProgramAliasedBindings::ProgramAliasedBindings() {}

ProgramAliasedBindings::~ProgramAliasedBindings() {}

void ProgramAliasedBindings::bindLocation(GLuint index, const std::string &name)
{
    mBindings[name] = ProgramBinding(index);

    // EXT_blend_func_extended spec: "If it specifies the base name of an array,
    // it identifies the resources associated with the first element of the array."
    //
    // Normalize array bindings so that "name" and "name[0]" map to the same entry.
    // If this binding is of the form "name[0]", then mark the "name" binding as
    // aliased but do not update it yet in case "name" is not actually an array.
    size_t nameLengthWithoutArrayIndex;
    unsigned int arrayIndex = ParseArrayIndex(name, &nameLengthWithoutArrayIndex);
    if (arrayIndex == 0)
    {
        std::string baseName = name.substr(0u, nameLengthWithoutArrayIndex);
        auto iter            = mBindings.find(baseName);
        if (iter != mBindings.end())
        {
            iter->second.aliased = true;
        }
    }
}

int ProgramAliasedBindings::getBindingByName(const std::string &name) const
{
    auto iter = mBindings.find(name);
    return (iter != mBindings.end()) ? iter->second.location : -1;
}

int ProgramAliasedBindings::getBindingByLocation(GLuint location) const
{
    for (const auto &iter : mBindings)
    {
        if (iter.second.location == location)
        {
            return iter.second.location;
        }
    }
    return -1;
}

int ProgramAliasedBindings::getBinding(const sh::ShaderVariable &variable) const
{
    const std::string &name = variable.name;

    // Check with the normalized array name if applicable.
    if (variable.isArray())
    {
        size_t nameLengthWithoutArrayIndex;
        unsigned int arrayIndex = ParseArrayIndex(name, &nameLengthWithoutArrayIndex);
        if (arrayIndex == 0)
        {
            std::string baseName = name.substr(0u, nameLengthWithoutArrayIndex);
            auto iter            = mBindings.find(baseName);
            // If "name" exists and is not aliased, that means it was modified more
            // recently than its "name[0]" form and should be used instead of that.
            if (iter != mBindings.end() && !iter->second.aliased)
            {
                return iter->second.location;
            }
        }
        else if (arrayIndex == GL_INVALID_INDEX)
        {
            auto iter = mBindings.find(variable.name);
            // If "name" exists and is not aliased, that means it was modified more
            // recently than its "name[0]" form and should be used instead of that.
            if (iter != mBindings.end() && !iter->second.aliased)
            {
                return iter->second.location;
            }
            // The base name was aliased, so use the name with the array notation.
            return getBindingByName(name + "[0]");
        }
    }

    return getBindingByName(name);
}

ProgramAliasedBindings::const_iterator ProgramAliasedBindings::begin() const
{
    return mBindings.begin();
}

ProgramAliasedBindings::const_iterator ProgramAliasedBindings::end() const
{
    return mBindings.end();
}

std::map<std::string, ProgramBinding> ProgramAliasedBindings::getStableIterationMap() const
{
    return std::map<std::string, ProgramBinding>(mBindings.begin(), mBindings.end());
}

// ImageBinding implementation.
ImageBinding::ImageBinding(size_t count, TextureType textureTypeIn)
    : textureType(textureTypeIn), boundImageUnits(count, 0)
{}
ImageBinding::ImageBinding(GLuint imageUnit, size_t count, TextureType textureTypeIn)
    : textureType(textureTypeIn)
{
    for (size_t index = 0; index < count; ++index)
    {
        boundImageUnits.push_back(imageUnit + static_cast<GLuint>(index));
    }
}

ImageBinding::ImageBinding(const ImageBinding &other) = default;

ImageBinding::~ImageBinding() = default;

// ProgramState implementation.
ProgramState::ProgramState()
    : mLabel(),
      mAttachedShaders{},
      mLocationsUsedForXfbExtension(0),
      mBinaryRetrieveableHint(false),
      mSeparable(false),
      mNumViews(-1),
      mDrawIDLocation(-1),
      mBaseVertexLocation(-1),
      mBaseInstanceLocation(-1),
      mCachedBaseVertex(0),
      mCachedBaseInstance(0),
      mExecutable(new ProgramExecutable())
{
    mComputeShaderLocalSize.fill(1);
}

ProgramState::~ProgramState()
{
    ASSERT(!hasAttachedShader());
}

const std::string &ProgramState::getLabel()
{
    return mLabel;
}

Shader *ProgramState::getAttachedShader(ShaderType shaderType) const
{
    ASSERT(shaderType != ShaderType::InvalidEnum);
    return mAttachedShaders[shaderType];
}

GLuint ProgramState::getUniformIndexFromName(const std::string &name) const
{
    return GetResourceIndexFromName(mExecutable->mUniforms, name);
}

GLuint ProgramState::getBufferVariableIndexFromName(const std::string &name) const
{
    return GetResourceIndexFromName(mBufferVariables, name);
}

GLuint ProgramState::getUniformIndexFromLocation(UniformLocation location) const
{
    ASSERT(location.value >= 0 && static_cast<size_t>(location.value) < mUniformLocations.size());
    return mUniformLocations[location.value].index;
}

Optional<GLuint> ProgramState::getSamplerIndex(UniformLocation location) const
{
    GLuint index = getUniformIndexFromLocation(location);
    if (!isSamplerUniformIndex(index))
    {
        return Optional<GLuint>::Invalid();
    }

    return getSamplerIndexFromUniformIndex(index);
}

bool ProgramState::isSamplerUniformIndex(GLuint index) const
{
    return mExecutable->mSamplerUniformRange.contains(index);
}

GLuint ProgramState::getSamplerIndexFromUniformIndex(GLuint uniformIndex) const
{
    ASSERT(isSamplerUniformIndex(uniformIndex));
    return uniformIndex - mExecutable->mSamplerUniformRange.low();
}

GLuint ProgramState::getUniformIndexFromSamplerIndex(GLuint samplerIndex) const
{
    return mExecutable->getUniformIndexFromSamplerIndex(samplerIndex);
}

bool ProgramState::isImageUniformIndex(GLuint index) const
{
    return mExecutable->mImageUniformRange.contains(index);
}

GLuint ProgramState::getImageIndexFromUniformIndex(GLuint uniformIndex) const
{
    ASSERT(isImageUniformIndex(uniformIndex));
    return uniformIndex - mExecutable->mImageUniformRange.low();
}

GLuint ProgramState::getAttributeLocation(const std::string &name) const
{
    for (const sh::ShaderVariable &attribute : mExecutable->mProgramInputs)
    {
        if (attribute.name == name)
        {
            return attribute.location;
        }
    }

    return static_cast<GLuint>(-1);
}

bool ProgramState::hasAttachedShader() const
{
    for (const Shader *shader : mAttachedShaders)
    {
        if (shader)
        {
            return true;
        }
    }
    return false;
}

ShaderType ProgramState::getFirstAttachedShaderStageType() const
{
    const ShaderBitSet linkedStages = mExecutable->getLinkedShaderStages();
    if (linkedStages.none())
    {
        return ShaderType::InvalidEnum;
    }

    return linkedStages.first();
}

ShaderType ProgramState::getLastAttachedShaderStageType() const
{
    const ShaderBitSet linkedStages = mExecutable->getLinkedShaderStages();
    if (linkedStages.none())
    {
        return ShaderType::InvalidEnum;
    }

    return linkedStages.last();
}

ShaderType ProgramState::getAttachedTransformFeedbackStage() const
{
    if (mAttachedShaders[ShaderType::Geometry])
    {
        return ShaderType::Geometry;
    }
    if (mAttachedShaders[ShaderType::TessEvaluation])
    {
        return ShaderType::TessEvaluation;
    }
    return ShaderType::Vertex;
}

Program::Program(rx::GLImplFactory *factory, ShaderProgramManager *manager, ShaderProgramID handle)
    : mSerial(factory->generateSerial()),
      mProgram(factory->createProgram(mState)),
      mValidated(false),
      mLinked(false),
      mDeleteStatus(false),
      mRefCount(0),
      mResourceManager(manager),
      mHandle(handle)
{
    ASSERT(mProgram);

    unlink();
}

Program::~Program()
{
    ASSERT(!mProgram);
}

void Program::onDestroy(const Context *context)
{
    resolveLink(context);
    for (ShaderType shaderType : AllShaderTypes())
    {
        if (mState.mAttachedShaders[shaderType])
        {
            mState.mAttachedShaders[shaderType]->release(context);
            mState.mAttachedShaders[shaderType] = nullptr;
        }
    }

    mProgram->destroy(context);

    ASSERT(!mState.hasAttachedShader());
    SafeDelete(mProgram);

    delete this;
}
ShaderProgramID Program::id() const
{
    ASSERT(!mLinkingState);
    return mHandle;
}

angle::Result Program::setLabel(const Context *context, const std::string &label)
{
    ASSERT(!mLinkingState);
    mState.mLabel = label;

    if (mProgram)
    {
        return mProgram->onLabelUpdate(context);
    }
    return angle::Result::Continue;
}

const std::string &Program::getLabel() const
{
    ASSERT(!mLinkingState);
    return mState.mLabel;
}

void Program::attachShader(Shader *shader)
{
    ShaderType shaderType = shader->getType();
    ASSERT(shaderType != ShaderType::InvalidEnum);

    mState.mAttachedShaders[shaderType] = shader;
    mState.mAttachedShaders[shaderType]->addRef();
}

void Program::detachShader(const Context *context, Shader *shader)
{
    resolveLink(context);
    ShaderType shaderType = shader->getType();
    ASSERT(shaderType != ShaderType::InvalidEnum);

    ASSERT(mState.mAttachedShaders[shaderType] == shader);
    shader->release(context);
    mState.mAttachedShaders[shaderType] = nullptr;
}

int Program::getAttachedShadersCount() const
{
    ASSERT(!mLinkingState);
    int numAttachedShaders = 0;
    for (const Shader *shader : mState.mAttachedShaders)
    {
        if (shader)
        {
            ++numAttachedShaders;
        }
    }

    return numAttachedShaders;
}

Shader *Program::getAttachedShader(ShaderType shaderType) const
{
    ASSERT(!mLinkingState);
    return mState.getAttachedShader(shaderType);
}

void Program::bindAttributeLocation(GLuint index, const char *name)
{
    ASSERT(!mLinkingState);
    mAttributeBindings.bindLocation(index, name);
}

void Program::bindUniformLocation(UniformLocation location, const char *name)
{
    ASSERT(!mLinkingState);
    mState.mUniformLocationBindings.bindLocation(location.value, name);
}

void Program::bindFragmentOutputLocation(GLuint index, const char *name)
{
    mFragmentOutputLocations.bindLocation(index, name);
}

void Program::bindFragmentOutputIndex(GLuint index, const char *name)
{
    mFragmentOutputIndexes.bindLocation(index, name);
}

angle::Result Program::link(const Context *context)
{
    angle::Result result = linkImpl(context);

    // Avoid having two ProgramExecutables if the link failed and the Program had successfully
    // linked previously.
    if (mLinkingState && mLinkingState->linkedExecutable)
    {
        mState.mExecutable = mLinkingState->linkedExecutable;
    }

    return result;
}

// The attached shaders are checked for linking errors by matching up their variables.
// Uniform, input and output variables get collected.
// The code gets compiled into binaries.
angle::Result Program::linkImpl(const Context *context)
{
    ASSERT(!mLinkingState);
    // Don't make any local variables pointing to anything within the ProgramExecutable, since
    // unlink() could make a new ProgramExecutable making any references/pointers invalid.
    auto *platform   = ANGLEPlatformCurrent();
    double startTime = platform->currentTime(platform);

    // Unlink the program, but do not clear the validation-related caching yet, since we can still
    // use the previously linked program if linking the shaders fails.
    mLinked = false;

    mState.mExecutable->resetInfoLog();

    // Validate we have properly attached shaders before checking the cache.
    if (!linkValidateShaders(context, mState.mExecutable->getInfoLog()))
    {
        return angle::Result::Continue;
    }

    egl::BlobCache::Key programHash = {0};
    MemoryProgramCache *cache       = context->getMemoryProgramCache();

    // TODO: http://anglebug.com/4530: Enable program caching for separable programs
    if (cache && !isSeparable())
    {
        std::lock_guard<std::mutex> cacheLock(context->getProgramCacheMutex());
        angle::Result cacheResult = cache->getProgram(context, this, &programHash);
        ANGLE_TRY(cacheResult);

        // Check explicitly for Continue, Incomplete means a cache miss
        if (cacheResult == angle::Result::Continue)
        {
            std::scoped_lock lock(mHistogramMutex);
            // Succeeded in loading the binaries in the front-end, back end may still be loading
            // asynchronously
            double delta = platform->currentTime(platform) - startTime;
            int us       = static_cast<int>(delta * 1000000.0);
            ANGLE_HISTOGRAM_COUNTS("GPU.ANGLE.ProgramCache.ProgramCacheHitTimeUS", us);
            return angle::Result::Continue;
        }
    }

    // Cache load failed, fall through to normal linking.
    unlink();
    InfoLog &infoLog = mState.mExecutable->getInfoLog();

    // Re-link shaders after the unlink call.
    bool result = linkValidateShaders(context, infoLog);
    ASSERT(result);

    std::unique_ptr<LinkingState> linkingState(new LinkingState());
    ProgramMergedVaryings mergedVaryings;
    LinkingVariables linkingVariables(context, mState);
    ProgramLinkedResources &resources = linkingState->resources;

    resources.init(&mState.mExecutable->mUniformBlocks, &mState.mExecutable->mUniforms,
                   &mState.mExecutable->mShaderStorageBlocks, &mState.mBufferVariables,
                   &mState.mExecutable->mAtomicCounterBuffers);

    // TODO: Fix incomplete linking. http://anglebug.com/6358
    updateLinkedShaderStages();

    InitUniformBlockLinker(context, mState, &resources.uniformBlockLinker);
    InitShaderStorageBlockLinker(context, mState, &resources.shaderStorageBlockLinker);

    if (mState.mAttachedShaders[ShaderType::Compute])
    {
        GLuint combinedImageUniforms = 0;
        if (!linkUniforms(context, &resources.unusedUniforms, &combinedImageUniforms, infoLog))
        {
            return angle::Result::Continue;
        }

        GLuint combinedShaderStorageBlocks = 0u;
        if (!LinkValidateProgramInterfaceBlocks(context,
                                                mState.mExecutable->getLinkedShaderStages(),
                                                resources, infoLog, &combinedShaderStorageBlocks))
        {
            return angle::Result::Continue;
        }

        // [OpenGL ES 3.1] Chapter 8.22 Page 203:
        // A link error will be generated if the sum of the number of active image uniforms used in
        // all shaders, the number of active shader storage blocks, and the number of active
        // fragment shader outputs exceeds the implementation-dependent value of
        // MAX_COMBINED_SHADER_OUTPUT_RESOURCES.
        if (combinedImageUniforms + combinedShaderStorageBlocks >
            static_cast<GLuint>(context->getCaps().maxCombinedShaderOutputResources))
        {
            infoLog
                << "The sum of the number of active image uniforms, active shader storage blocks "
                   "and active fragment shader outputs exceeds "
                   "MAX_COMBINED_SHADER_OUTPUT_RESOURCES ("
                << context->getCaps().maxCombinedShaderOutputResources << ")";
            return angle::Result::Continue;
        }
    }
    else
    {
        if (!linkAttributes(context, infoLog))
        {
            return angle::Result::Continue;
        }

        if (!linkVaryings(context, infoLog))
        {
            return angle::Result::Continue;
        }

        GLuint combinedImageUniforms = 0;
        if (!linkUniforms(context, &resources.unusedUniforms, &combinedImageUniforms, infoLog))
        {
            return angle::Result::Continue;
        }

        GLuint combinedShaderStorageBlocks = 0u;
        if (!LinkValidateProgramInterfaceBlocks(context,
                                                mState.mExecutable->getLinkedShaderStages(),
                                                resources, infoLog, &combinedShaderStorageBlocks))
        {
            return angle::Result::Continue;
        }

        if (!LinkValidateProgramGlobalNames(infoLog, getExecutable(), linkingVariables))
        {
            return angle::Result::Continue;
        }

        gl::Shader *vertexShader = mState.mAttachedShaders[ShaderType::Vertex];
        if (vertexShader)
        {
            mState.mNumViews = vertexShader->getNumViews(context);
            mState.mSpecConstUsageBits |= vertexShader->getSpecConstUsageBits();
        }

        gl::Shader *fragmentShader = mState.mAttachedShaders[ShaderType::Fragment];
        if (fragmentShader)
        {
            if (!mState.mExecutable->linkValidateOutputVariables(
                    context->getCaps(), context->getExtensions(), context->getClientVersion(),
                    combinedImageUniforms, combinedShaderStorageBlocks,
                    fragmentShader->getActiveOutputVariables(context),
                    fragmentShader->getShaderVersion(context), mFragmentOutputLocations,
                    mFragmentOutputIndexes))
            {
                return angle::Result::Continue;
            }

            mState.mExecutable->mHasDiscard = fragmentShader->hasDiscard();
            mState.mExecutable->mEnablesPerSampleShading =
                fragmentShader->enablesPerSampleShading();
            mState.mExecutable->mAdvancedBlendEquations =
                fragmentShader->getAdvancedBlendEquations();
            mState.mSpecConstUsageBits |= fragmentShader->getSpecConstUsageBits();
        }

        mergedVaryings = GetMergedVaryingsFromLinkingVariables(linkingVariables);
        if (!mState.mExecutable->linkMergedVaryings(
                context, mergedVaryings, mState.mTransformFeedbackVaryingNames, linkingVariables,
                isSeparable(), &resources.varyingPacking))
        {
            return angle::Result::Continue;
        }
    }

    mState.mExecutable->saveLinkedStateInfo(context, mState);

    mLinkingState                    = std::move(linkingState);
    mLinkingState->linkingFromBinary = false;
    mLinkingState->programHash       = programHash;
    mLinkingState->linkEvent         = mProgram->link(context, resources, infoLog, mergedVaryings);

    // Must be after mProgram->link() to avoid misleading the linker about output variables.
    mState.updateProgramInterfaceInputs(context);
    mState.updateProgramInterfaceOutputs(context);

    if (mState.mSeparable)
    {
        mLinkingState->linkedExecutable = mState.mExecutable;
    }

    return angle::Result::Continue;
}

bool Program::isLinking() const
{
    return (mLinkingState.get() && mLinkingState->linkEvent &&
            mLinkingState->linkEvent->isLinking());
}

void Program::resolveLinkImpl(const Context *context)
{
    ASSERT(mLinkingState.get());

    angle::Result result = mLinkingState->linkEvent->wait(context);

    mLinked                                    = result == angle::Result::Continue;
    std::unique_ptr<LinkingState> linkingState = std::move(mLinkingState);
    if (!mLinked)
    {
        mState.mExecutable->reset(false);
        return;
    }

    if (linkingState->linkingFromBinary)
    {
        // All internal Program state is already loaded from the binary.
        return;
    }

    initInterfaceBlockBindings();

    // According to GLES 3.0/3.1 spec for LinkProgram and UseProgram,
    // Only successfully linked program can replace the executables.
    ASSERT(mLinked);

    // Mark implementation-specific unreferenced uniforms as ignored.
    std::vector<ImageBinding> *imageBindings = getExecutable().getImageBindings();
    mProgram->markUnusedUniformLocations(&mState.mUniformLocations,
                                         &mState.mExecutable->mSamplerBindings, imageBindings);

    // Must be called after markUnusedUniformLocations.
    postResolveLink(context);

    // Save to the program cache.
    std::lock_guard<std::mutex> cacheLock(context->getProgramCacheMutex());
    MemoryProgramCache *cache = context->getMemoryProgramCache();
    // TODO: http://anglebug.com/4530: Enable program caching for separable programs
    if (cache && !isSeparable() &&
        (mState.mExecutable->mLinkedTransformFeedbackVaryings.empty() ||
         !context->getFrontendFeatures().disableProgramCachingForTransformFeedback.enabled))
    {
        if (cache->putProgram(linkingState->programHash, context, this) == angle::Result::Stop)
        {
            // Don't fail linking if putting the program binary into the cache fails, the program is
            // still usable.
            ANGLE_PERF_WARNING(context->getState().getDebug(), GL_DEBUG_SEVERITY_LOW,
                               "Failed to save linked program to memory program cache.");
        }
    }
}

void Program::updateLinkedShaderStages()
{
    mState.mExecutable->resetLinkedShaderStages();

    for (const Shader *shader : mState.mAttachedShaders)
    {
        if (shader)
        {
            mState.mExecutable->setLinkedShaderStages(shader->getType());
        }
    }
}

void ProgramState::updateActiveSamplers()
{
    mExecutable->mActiveSamplerRefCounts.fill(0);
    mExecutable->updateActiveSamplers(*this);
}

void ProgramState::updateProgramInterfaceInputs(const Context *context)
{
    const ShaderType firstAttachedShaderType = getFirstAttachedShaderStageType();

    if (firstAttachedShaderType == ShaderType::Vertex)
    {
        // Vertex attributes are already what we need, so nothing to do
        return;
    }

    Shader *shader = getAttachedShader(firstAttachedShaderType);
    ASSERT(shader);

    // Copy over each input varying, since the Shader could go away
    if (shader->getType() == ShaderType::Compute)
    {
        for (const sh::ShaderVariable &attribute : shader->getAllAttributes(context))
        {
            // Compute Shaders have the following built-in input variables.
            //
            // in uvec3 gl_NumWorkGroups;
            // in uvec3 gl_WorkGroupID;
            // in uvec3 gl_LocalInvocationID;
            // in uvec3 gl_GlobalInvocationID;
            // in uint  gl_LocalInvocationIndex;
            // They are all vecs or uints, so no special handling is required.
            mExecutable->mProgramInputs.emplace_back(attribute);
        }
    }
    else
    {
        for (const sh::ShaderVariable &varying : shader->getInputVaryings(context))
        {
            UpdateInterfaceVariable(&mExecutable->mProgramInputs, varying);
        }
    }
}

void ProgramState::updateProgramInterfaceOutputs(const Context *context)
{
    const ShaderType lastAttachedShaderType = getLastAttachedShaderStageType();

    if (lastAttachedShaderType == ShaderType::Fragment)
    {
        // Fragment outputs are already what we need, so nothing to do
        return;
    }
    if (lastAttachedShaderType == ShaderType::Compute)
    {
        // If the program only contains a Compute Shader, then there are no user-defined outputs.
        return;
    }

    Shader *shader = getAttachedShader(lastAttachedShaderType);
    ASSERT(shader);

    // Copy over each output varying, since the Shader could go away
    for (const sh::ShaderVariable &varying : shader->getOutputVaryings(context))
    {
        UpdateInterfaceVariable(&mExecutable->mOutputVariables, varying);
    }
}

// Returns the program object to an unlinked state, before re-linking, or at destruction
void Program::unlink()
{
    if (mLinkingState && mLinkingState->linkedExecutable)
    {
        // The new ProgramExecutable that we'll attempt to link with needs to start from a copy of
        // the last successfully linked ProgramExecutable, so we don't lose any state information.
        mState.mExecutable.reset(new ProgramExecutable(*mLinkingState->linkedExecutable));
    }
    mState.mExecutable->reset(true);

    mState.mUniformLocations.clear();
    mState.mBufferVariables.clear();
    mState.mComputeShaderLocalSize.fill(1);
    mState.mNumViews             = -1;
    mState.mDrawIDLocation       = -1;
    mState.mBaseVertexLocation   = -1;
    mState.mBaseInstanceLocation = -1;
    mState.mCachedBaseVertex     = 0;
    mState.mCachedBaseInstance   = 0;
    mState.mSpecConstUsageBits.reset();

    mValidated = false;

    mLinked = false;
}

angle::Result Program::loadBinary(const Context *context,
                                  GLenum binaryFormat,
                                  const void *binary,
                                  GLsizei length)
{
    ASSERT(!mLinkingState);
    unlink();
    InfoLog &infoLog = mState.mExecutable->getInfoLog();

    if (!angle::GetANGLEHasBinaryLoading())
    {
        return angle::Result::Incomplete;
    }

    ASSERT(binaryFormat == GL_PROGRAM_BINARY_ANGLE);
    if (binaryFormat != GL_PROGRAM_BINARY_ANGLE)
    {
        infoLog << "Invalid program binary format.";
        return angle::Result::Incomplete;
    }

    BinaryInputStream stream(binary, length);
    ANGLE_TRY(deserialize(context, stream, infoLog));
    // Currently we require the full shader text to compute the program hash.
    // We could also store the binary in the internal program cache.

    for (size_t uniformBlockIndex = 0;
         uniformBlockIndex < mState.mExecutable->getActiveUniformBlockCount(); ++uniformBlockIndex)
    {
        mDirtyBits.set(uniformBlockIndex);
    }

    // The rx::LinkEvent returned from ProgramImpl::load is a base class with multiple
    // implementations. In some implementations, a background thread is used to compile the
    // shaders. Any calls to the LinkEvent object, therefore, are racy and may interfere with
    // the operation.

    // We do not want to call LinkEvent::wait because that will cause the background thread
    // to finish its task before returning, thus defeating the purpose of background compilation.
    // We need to defer waiting on background compilation until the very last minute when we
    // absolutely need the results, such as when the developer binds the program or queries
    // for the completion status.

    // If load returns nullptr, we know for sure that the binary is not compatible with the backend.
    // The loaded binary could have been read from the on-disk shader cache and be corrupted or
    // serialized with different revision and subsystem id than the currently loaded backend.
    // Returning 'Incomplete' to the caller results in link happening using the original shader
    // sources.
    angle::Result result;
    std::unique_ptr<LinkingState> linkingState;
    std::unique_ptr<rx::LinkEvent> linkEvent = mProgram->load(context, &stream, infoLog);
    if (linkEvent)
    {
        linkingState                    = std::make_unique<LinkingState>();
        linkingState->linkingFromBinary = true;
        linkingState->linkEvent         = std::move(linkEvent);
        result                          = angle::Result::Continue;
    }
    else
    {
        result = angle::Result::Incomplete;
    }
    mLinkingState = std::move(linkingState);

    return result;
}

angle::Result Program::saveBinary(Context *context,
                                  GLenum *binaryFormat,
                                  void *binary,
                                  GLsizei bufSize,
                                  GLsizei *length) const
{
    ASSERT(!mLinkingState);
    if (binaryFormat)
    {
        *binaryFormat = GL_PROGRAM_BINARY_ANGLE;
    }

    angle::MemoryBuffer memoryBuf;
    ANGLE_TRY(serialize(context, &memoryBuf));

    GLsizei streamLength       = static_cast<GLsizei>(memoryBuf.size());
    const uint8_t *streamState = memoryBuf.data();

    if (streamLength > bufSize)
    {
        if (length)
        {
            *length = 0;
        }

        // TODO: This should be moved to the validation layer but computing the size of the binary
        // before saving it causes the save to happen twice.  It may be possible to write the binary
        // to a separate buffer, validate sizes and then copy it.
        ANGLE_CHECK(context, false, "Insufficient buffer size", GL_INVALID_OPERATION);
    }

    if (binary)
    {
        char *ptr = reinterpret_cast<char *>(binary);

        memcpy(ptr, streamState, streamLength);
        ptr += streamLength;

        ASSERT(ptr - streamLength == binary);
    }

    if (length)
    {
        *length = streamLength;
    }

    return angle::Result::Continue;
}

GLint Program::getBinaryLength(Context *context) const
{
    ASSERT(!mLinkingState);
    if (!mLinked)
    {
        return 0;
    }

    GLint length;
    angle::Result result =
        saveBinary(context, nullptr, nullptr, std::numeric_limits<GLint>::max(), &length);
    if (result != angle::Result::Continue)
    {
        return 0;
    }

    return length;
}

void Program::setBinaryRetrievableHint(bool retrievable)
{
    ASSERT(!mLinkingState);
    // TODO(jmadill) : replace with dirty bits
    mProgram->setBinaryRetrievableHint(retrievable);
    mState.mBinaryRetrieveableHint = retrievable;
}

bool Program::getBinaryRetrievableHint() const
{
    ASSERT(!mLinkingState);
    return mState.mBinaryRetrieveableHint;
}

void Program::setSeparable(bool separable)
{
    ASSERT(!mLinkingState);
    // TODO(yunchao) : replace with dirty bits
    if (mState.mSeparable != separable)
    {
        mProgram->setSeparable(separable);
        mState.mSeparable = separable;
    }
}

bool Program::isSeparable() const
{
    ASSERT(!mLinkingState);
    return mState.mSeparable;
}

void Program::deleteSelf(const Context *context)
{
    ASSERT(mRefCount == 0 && mDeleteStatus);
    mResourceManager->deleteProgram(context, mHandle);
}

unsigned int Program::getRefCount() const
{
    return mRefCount;
}

void Program::getAttachedShaders(GLsizei maxCount, GLsizei *count, ShaderProgramID *shaders) const
{
    ASSERT(!mLinkingState);
    int total = 0;

    for (const Shader *shader : mState.mAttachedShaders)
    {
        if (shader && (total < maxCount))
        {
            shaders[total] = shader->getHandle();
            ++total;
        }
    }

    if (count)
    {
        *count = total;
    }
}

GLuint Program::getAttributeLocation(const std::string &name) const
{
    ASSERT(!mLinkingState);
    return mState.getAttributeLocation(name);
}

void Program::getActiveAttribute(GLuint index,
                                 GLsizei bufsize,
                                 GLsizei *length,
                                 GLint *size,
                                 GLenum *type,
                                 GLchar *name) const
{
    ASSERT(!mLinkingState);
    if (!mLinked)
    {
        if (bufsize > 0)
        {
            name[0] = '\0';
        }

        if (length)
        {
            *length = 0;
        }

        *type = GL_NONE;
        *size = 1;
        return;
    }

    ASSERT(index < mState.mExecutable->getProgramInputs().size());
    const sh::ShaderVariable &attrib = mState.mExecutable->getProgramInputs()[index];

    if (bufsize > 0)
    {
        CopyStringToBuffer(name, attrib.name, bufsize, length);
    }

    // Always a single 'type' instance
    *size = 1;
    *type = attrib.type;
}

GLint Program::getActiveAttributeCount() const
{
    ASSERT(!mLinkingState);
    if (!mLinked)
    {
        return 0;
    }

    return static_cast<GLint>(mState.mExecutable->getProgramInputs().size());
}

GLint Program::getActiveAttributeMaxLength() const
{
    ASSERT(!mLinkingState);
    if (!mLinked)
    {
        return 0;
    }

    size_t maxLength = 0;

    for (const sh::ShaderVariable &attrib : mState.mExecutable->getProgramInputs())
    {
        maxLength = std::max(attrib.name.length() + 1, maxLength);
    }

    return static_cast<GLint>(maxLength);
}

const std::vector<sh::ShaderVariable> &Program::getAttributes() const
{
    ASSERT(!mLinkingState);
    return mState.mExecutable->getProgramInputs();
}

const sh::WorkGroupSize &Program::getComputeShaderLocalSize() const
{
    ASSERT(!mLinkingState);
    return mState.mComputeShaderLocalSize;
}

PrimitiveMode Program::getGeometryShaderInputPrimitiveType() const
{
    ASSERT(!mLinkingState && mState.mExecutable);
    return mState.mExecutable->getGeometryShaderInputPrimitiveType();
}
PrimitiveMode Program::getGeometryShaderOutputPrimitiveType() const
{
    ASSERT(!mLinkingState && mState.mExecutable);
    return mState.mExecutable->getGeometryShaderOutputPrimitiveType();
}
GLint Program::getGeometryShaderInvocations() const
{
    ASSERT(!mLinkingState && mState.mExecutable);
    return mState.mExecutable->getGeometryShaderInvocations();
}
GLint Program::getGeometryShaderMaxVertices() const
{
    ASSERT(!mLinkingState && mState.mExecutable);
    return mState.mExecutable->getGeometryShaderMaxVertices();
}

GLint Program::getTessControlShaderVertices() const
{
    ASSERT(!mLinkingState && mState.mExecutable);
    return mState.mExecutable->mTessControlShaderVertices;
}

GLenum Program::getTessGenMode() const
{
    ASSERT(!mLinkingState && mState.mExecutable);
    return mState.mExecutable->mTessGenMode;
}

GLenum Program::getTessGenPointMode() const
{
    ASSERT(!mLinkingState && mState.mExecutable);
    return mState.mExecutable->mTessGenPointMode;
}

GLenum Program::getTessGenSpacing() const
{
    ASSERT(!mLinkingState && mState.mExecutable);
    return mState.mExecutable->mTessGenSpacing;
}

GLenum Program::getTessGenVertexOrder() const
{
    ASSERT(!mLinkingState && mState.mExecutable);
    return mState.mExecutable->mTessGenVertexOrder;
}

const sh::ShaderVariable &Program::getInputResource(size_t index) const
{
    ASSERT(!mLinkingState);
    ASSERT(index < mState.mExecutable->getProgramInputs().size());
    return mState.mExecutable->getProgramInputs()[index];
}

GLuint Program::getInputResourceIndex(const GLchar *name) const
{
    ASSERT(!mLinkingState);
    const std::string nameString = StripLastArrayIndex(name);

    for (size_t index = 0; index < mState.mExecutable->getProgramInputs().size(); index++)
    {
        sh::ShaderVariable resource = getInputResource(index);
        if (resource.name == nameString)
        {
            return static_cast<GLuint>(index);
        }
    }

    return GL_INVALID_INDEX;
}

GLuint Program::getResourceMaxNameSize(const sh::ShaderVariable &resource, GLint max) const
{
    if (resource.isArray())
    {
        return std::max(max, clampCast<GLint>((resource.name + "[0]").size()));
    }
    else
    {
        return std::max(max, clampCast<GLint>((resource.name).size()));
    }
}

GLuint Program::getInputResourceMaxNameSize() const
{
    GLint max = 0;

    for (const sh::ShaderVariable &resource : mState.mExecutable->getProgramInputs())
    {
        max = getResourceMaxNameSize(resource, max);
    }

    return max;
}

GLuint Program::getOutputResourceMaxNameSize() const
{
    GLint max = 0;

    for (const sh::ShaderVariable &resource : mState.mExecutable->getOutputVariables())
    {
        max = getResourceMaxNameSize(resource, max);
    }

    return max;
}

GLuint Program::getResourceLocation(const GLchar *name, const sh::ShaderVariable &variable) const
{
    if (variable.isBuiltIn())
    {
        return GL_INVALID_INDEX;
    }

    GLint location = variable.location;
    if (variable.isArray())
    {
        size_t nameLengthWithoutArrayIndexOut;
        size_t arrayIndex = ParseArrayIndex(name, &nameLengthWithoutArrayIndexOut);
        // The 'name' string may not contain the array notation "[0]"
        if (arrayIndex != GL_INVALID_INDEX)
        {
            location += arrayIndex;
        }
    }

    return location;
}

GLuint Program::getInputResourceLocation(const GLchar *name) const
{
    const GLuint index = getInputResourceIndex(name);
    if (index == GL_INVALID_INDEX)
    {
        return index;
    }

    const sh::ShaderVariable &variable = getInputResource(index);

    return getResourceLocation(name, variable);
}

GLuint Program::getOutputResourceLocation(const GLchar *name) const
{
    const GLuint index = getOutputResourceIndex(name);
    if (index == GL_INVALID_INDEX)
    {
        return index;
    }

    const sh::ShaderVariable &variable = getOutputResource(index);

    return getResourceLocation(name, variable);
}

GLuint Program::getOutputResourceIndex(const GLchar *name) const
{
    ASSERT(!mLinkingState);
    const std::string nameString = StripLastArrayIndex(name);

    for (size_t index = 0; index < mState.mExecutable->getOutputVariables().size(); index++)
    {
        sh::ShaderVariable resource = getOutputResource(index);
        if (resource.name == nameString)
        {
            return static_cast<GLuint>(index);
        }
    }

    return GL_INVALID_INDEX;
}

size_t Program::getOutputResourceCount() const
{
    ASSERT(!mLinkingState);
    return (mLinked ? mState.mExecutable->getOutputVariables().size() : 0);
}

void Program::getResourceName(const std::string name,
                              GLsizei bufSize,
                              GLsizei *length,
                              GLchar *dest) const
{
    if (length)
    {
        *length = 0;
    }

    if (!mLinked)
    {
        if (bufSize > 0)
        {
            dest[0] = '\0';
        }
        return;
    }

    if (bufSize > 0)
    {
        CopyStringToBuffer(dest, name, bufSize, length);
    }
}

void Program::getInputResourceName(GLuint index,
                                   GLsizei bufSize,
                                   GLsizei *length,
                                   GLchar *name) const
{
    ASSERT(!mLinkingState);
    getResourceName(getInputResourceName(index), bufSize, length, name);
}

void Program::getOutputResourceName(GLuint index,
                                    GLsizei bufSize,
                                    GLsizei *length,
                                    GLchar *name) const
{
    ASSERT(!mLinkingState);
    getResourceName(getOutputResourceName(index), bufSize, length, name);
}

void Program::getUniformResourceName(GLuint index,
                                     GLsizei bufSize,
                                     GLsizei *length,
                                     GLchar *name) const
{
    ASSERT(!mLinkingState);
    ASSERT(index < mState.mExecutable->getUniforms().size());
    getResourceName(mState.mExecutable->getUniforms()[index].name, bufSize, length, name);
}

void Program::getBufferVariableResourceName(GLuint index,
                                            GLsizei bufSize,
                                            GLsizei *length,
                                            GLchar *name) const
{
    ASSERT(!mLinkingState);
    ASSERT(index < mState.mBufferVariables.size());
    getResourceName(mState.mBufferVariables[index].name, bufSize, length, name);
}

const std::string Program::getResourceName(const sh::ShaderVariable &resource) const
{
    std::string resourceName = resource.name;

    if (resource.isArray())
    {
        resourceName += "[0]";
    }

    return resourceName;
}

const std::string Program::getInputResourceName(GLuint index) const
{
    ASSERT(!mLinkingState);
    const sh::ShaderVariable &resource = getInputResource(index);

    return getResourceName(resource);
}

const std::string Program::getOutputResourceName(GLuint index) const
{
    ASSERT(!mLinkingState);
    const sh::ShaderVariable &resource = getOutputResource(index);

    return getResourceName(resource);
}

const sh::ShaderVariable &Program::getOutputResource(size_t index) const
{
    ASSERT(!mLinkingState);
--> --------------------

--> maximum size reached

--> --------------------