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kc3-lang/angle/src/libANGLE/Program.cpp

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  • Author : Geoff Lang
    Date : 2015-12-10 17:45:46
    Hash : 70d0f499
    Message : Implement GL_KHR_debug. BUG=angleproject:520 Change-Id: I9ced3e7ab1515feddf2ec103c26b2610a45b1784 Reviewed-on: https://chromium-review.googlesource.com/319830 Tryjob-Request: Geoff Lang <geofflang@chromium.org> Reviewed-by: Geoff Lang <geofflang@chromium.org> Tested-by: Geoff Lang <geofflang@chromium.org>

  • src/libANGLE/Program.cpp
  • //
    // Copyright (c) 2002-2014 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 "common/BitSetIterator.h"
    #include "common/debug.h"
    #include "common/platform.h"
    #include "common/utilities.h"
    #include "common/version.h"
    #include "compiler/translator/blocklayout.h"
    #include "libANGLE/Data.h"
    #include "libANGLE/ResourceManager.h"
    #include "libANGLE/features.h"
    #include "libANGLE/renderer/Renderer.h"
    #include "libANGLE/renderer/ProgramImpl.h"
    #include "libANGLE/queryconversions.h"
    
    namespace gl
    {
    
    namespace
    {
    
    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->writeInt(var.arraySize);
        stream->writeInt(var.staticUse);
        stream->writeString(var.structName);
        ASSERT(var.fields.empty());
    }
    
    void LoadShaderVar(BinaryInputStream *stream, sh::ShaderVariable *var)
    {
        var->type       = stream->readInt<GLenum>();
        var->precision  = stream->readInt<GLenum>();
        var->name       = stream->readString();
        var->mappedName = stream->readString();
        var->arraySize  = stream->readInt<unsigned int>();
        var->staticUse  = stream->readBool();
        var->structName = stream->readString();
    }
    
    // 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 (value == GL_TRUE ? 1.0f : 0.0f);
    }
    
    template <>
    GLint UniformStateQueryCast(GLboolean value)
    {
        return (value == GL_TRUE ? 1 : 0);
    }
    
    template <>
    GLuint UniformStateQueryCast(GLboolean value)
    {
        return (value == GL_TRUE ? 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);
        }
    }
    
    bool UniformInList(const std::vector<LinkedUniform> &list, const std::string &name)
    {
        for (const LinkedUniform &uniform : list)
        {
            if (uniform.name == name)
                return true;
        }
    
        return false;
    }
    
    }  // anonymous namespace
    
    const char *const g_fakepath = "C:\\fakepath";
    
    AttributeBindings::AttributeBindings()
    {
    }
    
    AttributeBindings::~AttributeBindings()
    {
    }
    
    InfoLog::InfoLog()
    {
    }
    
    InfoLog::~InfoLog()
    {
    }
    
    size_t InfoLog::getLength() const
    {
        const std::string &logString = mStream.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 str(mStream.str());
    
            if (!str.empty())
            {
                index = std::min(static_cast<size_t>(bufSize) - 1, str.length());
                memcpy(infoLog, str.c_str(), index);
            }
    
            infoLog[index] = '\0';
        }
    
        if (length)
        {
            *length = static_cast<GLsizei>(index);
        }
    }
    
    // append a santized 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)
    {
        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);
    
        mStream << message << std::endl;
    }
    
    void InfoLog::reset()
    {
    }
    
    VariableLocation::VariableLocation()
        : name(),
          element(0),
          index(0)
    {
    }
    
    VariableLocation::VariableLocation(const std::string &name, unsigned int element, unsigned int index)
        : name(name),
          element(element),
          index(index)
    {
    }
    
    Program::Data::Data()
        : mLabel(),
          mAttachedFragmentShader(nullptr),
          mAttachedVertexShader(nullptr),
          mTransformFeedbackBufferMode(GL_INTERLEAVED_ATTRIBS),
          mBinaryRetrieveableHint(false)
    {
    }
    
    Program::Data::~Data()
    {
        if (mAttachedVertexShader != nullptr)
        {
            mAttachedVertexShader->release();
        }
    
        if (mAttachedFragmentShader != nullptr)
        {
            mAttachedFragmentShader->release();
        }
    }
    
    const std::string &Program::Data::getLabel()
    {
        return mLabel;
    }
    
    const LinkedUniform *Program::Data::getUniformByName(const std::string &name) const
    {
        for (const LinkedUniform &linkedUniform : mUniforms)
        {
            if (linkedUniform.name == name)
            {
                return &linkedUniform;
            }
        }
    
        return nullptr;
    }
    
    GLint Program::Data::getUniformLocation(const std::string &name) const
    {
        size_t subscript     = GL_INVALID_INDEX;
        std::string baseName = gl::ParseUniformName(name, &subscript);
    
        for (size_t location = 0; location < mUniformLocations.size(); ++location)
        {
            const VariableLocation &uniformLocation = mUniformLocations[location];
            const LinkedUniform &uniform            = mUniforms[uniformLocation.index];
    
            if (uniform.name == baseName)
            {
                if ((uniform.isArray() && uniformLocation.element == subscript) ||
                    (subscript == GL_INVALID_INDEX))
                {
                    return static_cast<GLint>(location);
                }
            }
        }
    
        return -1;
    }
    
    GLuint Program::Data::getUniformIndex(const std::string &name) const
    {
        size_t subscript     = GL_INVALID_INDEX;
        std::string baseName = gl::ParseUniformName(name, &subscript);
    
        // The app is not allowed to specify array indices other than 0 for arrays of basic types
        if (subscript != 0 && subscript != GL_INVALID_INDEX)
        {
            return GL_INVALID_INDEX;
        }
    
        for (size_t index = 0; index < mUniforms.size(); index++)
        {
            const LinkedUniform &uniform = mUniforms[index];
            if (uniform.name == baseName)
            {
                if (uniform.isArray() || subscript == GL_INVALID_INDEX)
                {
                    return static_cast<GLuint>(index);
                }
            }
        }
    
        return GL_INVALID_INDEX;
    }
    
    Program::Program(rx::ImplFactory *factory, ResourceManager *manager, GLuint handle)
        : mProgram(factory->createProgram(mData)),
          mValidated(false),
          mLinked(false),
          mDeleteStatus(false),
          mRefCount(0),
          mResourceManager(manager),
          mHandle(handle),
          mSamplerUniformRange(0, 0)
    {
        ASSERT(mProgram);
    
        resetUniformBlockBindings();
        unlink();
    }
    
    Program::~Program()
    {
        unlink(true);
    
        SafeDelete(mProgram);
    }
    
    void Program::setLabel(const std::string &label)
    {
        mData.mLabel = label;
    }
    
    const std::string &Program::getLabel() const
    {
        return mData.mLabel;
    }
    
    bool Program::attachShader(Shader *shader)
    {
        if (shader->getType() == GL_VERTEX_SHADER)
        {
            if (mData.mAttachedVertexShader)
            {
                return false;
            }
    
            mData.mAttachedVertexShader = shader;
            mData.mAttachedVertexShader->addRef();
        }
        else if (shader->getType() == GL_FRAGMENT_SHADER)
        {
            if (mData.mAttachedFragmentShader)
            {
                return false;
            }
    
            mData.mAttachedFragmentShader = shader;
            mData.mAttachedFragmentShader->addRef();
        }
        else UNREACHABLE();
    
        return true;
    }
    
    bool Program::detachShader(Shader *shader)
    {
        if (shader->getType() == GL_VERTEX_SHADER)
        {
            if (mData.mAttachedVertexShader != shader)
            {
                return false;
            }
    
            shader->release();
            mData.mAttachedVertexShader = nullptr;
        }
        else if (shader->getType() == GL_FRAGMENT_SHADER)
        {
            if (mData.mAttachedFragmentShader != shader)
            {
                return false;
            }
    
            shader->release();
            mData.mAttachedFragmentShader = nullptr;
        }
        else UNREACHABLE();
    
        return true;
    }
    
    int Program::getAttachedShadersCount() const
    {
        return (mData.mAttachedVertexShader ? 1 : 0) + (mData.mAttachedFragmentShader ? 1 : 0);
    }
    
    void AttributeBindings::bindAttributeLocation(GLuint index, const char *name)
    {
        if (index < MAX_VERTEX_ATTRIBS)
        {
            for (int i = 0; i < MAX_VERTEX_ATTRIBS; i++)
            {
                mAttributeBinding[i].erase(name);
            }
    
            mAttributeBinding[index].insert(name);
        }
    }
    
    void Program::bindAttributeLocation(GLuint index, const char *name)
    {
        mAttributeBindings.bindAttributeLocation(index, name);
    }
    
    // Links the HLSL code of the vertex and pixel shader by matching up their varyings,
    // compiling them into binaries, determining the attribute mappings, and collecting
    // a list of uniforms
    Error Program::link(const gl::Data &data)
    {
        unlink(false);
    
        mInfoLog.reset();
        resetUniformBlockBindings();
    
        if (!mData.mAttachedFragmentShader || !mData.mAttachedFragmentShader->isCompiled())
        {
            return Error(GL_NO_ERROR);
        }
        ASSERT(mData.mAttachedFragmentShader->getType() == GL_FRAGMENT_SHADER);
    
        if (!mData.mAttachedVertexShader || !mData.mAttachedVertexShader->isCompiled())
        {
            return Error(GL_NO_ERROR);
        }
        ASSERT(mData.mAttachedVertexShader->getType() == GL_VERTEX_SHADER);
    
        if (!linkAttributes(data, mInfoLog, mAttributeBindings, mData.mAttachedVertexShader))
        {
            return Error(GL_NO_ERROR);
        }
    
        if (!linkVaryings(mInfoLog, mData.mAttachedVertexShader, mData.mAttachedFragmentShader))
        {
            return Error(GL_NO_ERROR);
        }
    
        if (!linkUniforms(mInfoLog, *data.caps))
        {
            return Error(GL_NO_ERROR);
        }
    
        if (!linkUniformBlocks(mInfoLog, *data.caps))
        {
            return Error(GL_NO_ERROR);
        }
    
        const auto &mergedVaryings = getMergedVaryings();
    
        if (!linkValidateTransformFeedback(mInfoLog, mergedVaryings, *data.caps))
        {
            return Error(GL_NO_ERROR);
        }
    
        linkOutputVariables();
    
        rx::LinkResult result = mProgram->link(data, mInfoLog);
        if (result.error.isError() || !result.linkSuccess)
        {
            return result.error;
        }
    
        gatherTransformFeedbackVaryings(mergedVaryings);
        gatherInterfaceBlockInfo();
    
        mLinked = true;
        return gl::Error(GL_NO_ERROR);
    }
    
    int AttributeBindings::getAttributeBinding(const std::string &name) const
    {
        for (int location = 0; location < MAX_VERTEX_ATTRIBS; location++)
        {
            if (mAttributeBinding[location].find(name) != mAttributeBinding[location].end())
            {
                return location;
            }
        }
    
        return -1;
    }
    
    // Returns the program object to an unlinked state, before re-linking, or at destruction
    void Program::unlink(bool destroy)
    {
        if (destroy)   // Object being destructed
        {
            if (mData.mAttachedFragmentShader)
            {
                mData.mAttachedFragmentShader->release();
                mData.mAttachedFragmentShader = nullptr;
            }
    
            if (mData.mAttachedVertexShader)
            {
                mData.mAttachedVertexShader->release();
                mData.mAttachedVertexShader = nullptr;
            }
        }
    
        mData.mAttributes.clear();
        mData.mActiveAttribLocationsMask.reset();
        mData.mTransformFeedbackVaryingVars.clear();
        mData.mUniforms.clear();
        mData.mUniformLocations.clear();
        mData.mUniformBlocks.clear();
        mData.mOutputVariables.clear();
    
        mValidated = false;
    
        mLinked = false;
    }
    
    bool Program::isLinked() const
    {
        return mLinked;
    }
    
    Error Program::loadBinary(GLenum binaryFormat, const void *binary, GLsizei length)
    {
        unlink(false);
    
    #if ANGLE_PROGRAM_BINARY_LOAD != ANGLE_ENABLED
        return Error(GL_NO_ERROR);
    #else
        ASSERT(binaryFormat == GL_PROGRAM_BINARY_ANGLE);
        if (binaryFormat != GL_PROGRAM_BINARY_ANGLE)
        {
            mInfoLog << "Invalid program binary format.";
            return Error(GL_NO_ERROR);
        }
    
        BinaryInputStream stream(binary, length);
    
        int majorVersion = stream.readInt<int>();
        int minorVersion = stream.readInt<int>();
        if (majorVersion != ANGLE_MAJOR_VERSION || minorVersion != ANGLE_MINOR_VERSION)
        {
            mInfoLog << "Invalid program binary version.";
            return Error(GL_NO_ERROR);
        }
    
        unsigned char commitString[ANGLE_COMMIT_HASH_SIZE];
        stream.readBytes(commitString, ANGLE_COMMIT_HASH_SIZE);
        if (memcmp(commitString, ANGLE_COMMIT_HASH, sizeof(unsigned char) * ANGLE_COMMIT_HASH_SIZE) != 0)
        {
            mInfoLog << "Invalid program binary version.";
            return Error(GL_NO_ERROR);
        }
    
        static_assert(MAX_VERTEX_ATTRIBS <= sizeof(unsigned long) * 8,
                      "Too many vertex attribs for mask");
        mData.mActiveAttribLocationsMask = stream.readInt<unsigned long>();
    
        unsigned int attribCount = stream.readInt<unsigned int>();
        ASSERT(mData.mAttributes.empty());
        for (unsigned int attribIndex = 0; attribIndex < attribCount; ++attribIndex)
        {
            sh::Attribute attrib;
            LoadShaderVar(&stream, &attrib);
            attrib.location = stream.readInt<int>();
            mData.mAttributes.push_back(attrib);
        }
    
        unsigned int uniformCount = stream.readInt<unsigned int>();
        ASSERT(mData.mUniforms.empty());
        for (unsigned int uniformIndex = 0; uniformIndex < uniformCount; ++uniformIndex)
        {
            LinkedUniform uniform;
            LoadShaderVar(&stream, &uniform);
    
            uniform.blockIndex                 = stream.readInt<int>();
            uniform.blockInfo.offset           = stream.readInt<int>();
            uniform.blockInfo.arrayStride      = stream.readInt<int>();
            uniform.blockInfo.matrixStride     = stream.readInt<int>();
            uniform.blockInfo.isRowMajorMatrix = stream.readBool();
    
            mData.mUniforms.push_back(uniform);
        }
    
        const unsigned int uniformIndexCount = stream.readInt<unsigned int>();
        ASSERT(mData.mUniformLocations.empty());
        for (unsigned int uniformIndexIndex = 0; uniformIndexIndex < uniformIndexCount;
             uniformIndexIndex++)
        {
            VariableLocation variable;
            stream.readString(&variable.name);
            stream.readInt(&variable.element);
            stream.readInt(&variable.index);
    
            mData.mUniformLocations.push_back(variable);
        }
    
        unsigned int uniformBlockCount = stream.readInt<unsigned int>();
        ASSERT(mData.mUniformBlocks.empty());
        for (unsigned int uniformBlockIndex = 0; uniformBlockIndex < uniformBlockCount;
             ++uniformBlockIndex)
        {
            UniformBlock uniformBlock;
            stream.readString(&uniformBlock.name);
            stream.readBool(&uniformBlock.isArray);
            stream.readInt(&uniformBlock.arrayElement);
            stream.readInt(&uniformBlock.dataSize);
            stream.readBool(&uniformBlock.vertexStaticUse);
            stream.readBool(&uniformBlock.fragmentStaticUse);
    
            unsigned int numMembers = stream.readInt<unsigned int>();
            for (unsigned int blockMemberIndex = 0; blockMemberIndex < numMembers; blockMemberIndex++)
            {
                uniformBlock.memberUniformIndexes.push_back(stream.readInt<unsigned int>());
            }
    
            mData.mUniformBlocks.push_back(uniformBlock);
        }
    
        unsigned int transformFeedbackVaryingCount = stream.readInt<unsigned int>();
        ASSERT(mData.mTransformFeedbackVaryingVars.empty());
        for (unsigned int transformFeedbackVaryingIndex = 0;
            transformFeedbackVaryingIndex < transformFeedbackVaryingCount;
            ++transformFeedbackVaryingIndex)
        {
            sh::Varying varying;
            stream.readInt(&varying.arraySize);
            stream.readInt(&varying.type);
            stream.readString(&varying.name);
    
            mData.mTransformFeedbackVaryingVars.push_back(varying);
        }
    
        stream.readInt(&mData.mTransformFeedbackBufferMode);
    
        unsigned int outputVarCount = stream.readInt<unsigned int>();
        for (unsigned int outputIndex = 0; outputIndex < outputVarCount; ++outputIndex)
        {
            int locationIndex = stream.readInt<int>();
            VariableLocation locationData;
            stream.readInt(&locationData.element);
            stream.readInt(&locationData.index);
            stream.readString(&locationData.name);
            mData.mOutputVariables[locationIndex] = locationData;
        }
    
        stream.readInt(&mSamplerUniformRange.start);
        stream.readInt(&mSamplerUniformRange.end);
    
        rx::LinkResult result = mProgram->load(mInfoLog, &stream);
        if (result.error.isError() || !result.linkSuccess)
        {
            return result.error;
        }
    
        mLinked = true;
        return Error(GL_NO_ERROR);
    #endif // #if ANGLE_PROGRAM_BINARY_LOAD == ANGLE_ENABLED
    }
    
    Error Program::saveBinary(GLenum *binaryFormat, void *binary, GLsizei bufSize, GLsizei *length) const
    {
        if (binaryFormat)
        {
            *binaryFormat = GL_PROGRAM_BINARY_ANGLE;
        }
    
        BinaryOutputStream stream;
    
        stream.writeInt(ANGLE_MAJOR_VERSION);
        stream.writeInt(ANGLE_MINOR_VERSION);
        stream.writeBytes(reinterpret_cast<const unsigned char*>(ANGLE_COMMIT_HASH), ANGLE_COMMIT_HASH_SIZE);
    
        stream.writeInt(mData.mActiveAttribLocationsMask.to_ulong());
    
        stream.writeInt(mData.mAttributes.size());
        for (const sh::Attribute &attrib : mData.mAttributes)
        {
            WriteShaderVar(&stream, attrib);
            stream.writeInt(attrib.location);
        }
    
        stream.writeInt(mData.mUniforms.size());
        for (const gl::LinkedUniform &uniform : mData.mUniforms)
        {
            WriteShaderVar(&stream, uniform);
    
            // FIXME: referenced
    
            stream.writeInt(uniform.blockIndex);
            stream.writeInt(uniform.blockInfo.offset);
            stream.writeInt(uniform.blockInfo.arrayStride);
            stream.writeInt(uniform.blockInfo.matrixStride);
            stream.writeInt(uniform.blockInfo.isRowMajorMatrix);
        }
    
        stream.writeInt(mData.mUniformLocations.size());
        for (const auto &variable : mData.mUniformLocations)
        {
            stream.writeString(variable.name);
            stream.writeInt(variable.element);
            stream.writeInt(variable.index);
        }
    
        stream.writeInt(mData.mUniformBlocks.size());
        for (const UniformBlock &uniformBlock : mData.mUniformBlocks)
        {
            stream.writeString(uniformBlock.name);
            stream.writeInt(uniformBlock.isArray);
            stream.writeInt(uniformBlock.arrayElement);
            stream.writeInt(uniformBlock.dataSize);
    
            stream.writeInt(uniformBlock.vertexStaticUse);
            stream.writeInt(uniformBlock.fragmentStaticUse);
    
            stream.writeInt(uniformBlock.memberUniformIndexes.size());
            for (unsigned int memberUniformIndex : uniformBlock.memberUniformIndexes)
            {
                stream.writeInt(memberUniformIndex);
            }
        }
    
        stream.writeInt(mData.mTransformFeedbackVaryingVars.size());
        for (const sh::Varying &varying : mData.mTransformFeedbackVaryingVars)
        {
            stream.writeInt(varying.arraySize);
            stream.writeInt(varying.type);
            stream.writeString(varying.name);
        }
    
        stream.writeInt(mData.mTransformFeedbackBufferMode);
    
        stream.writeInt(mData.mOutputVariables.size());
        for (const auto &outputPair : mData.mOutputVariables)
        {
            stream.writeInt(outputPair.first);
            stream.writeInt(outputPair.second.element);
            stream.writeInt(outputPair.second.index);
            stream.writeString(outputPair.second.name);
        }
    
        stream.writeInt(mSamplerUniformRange.start);
        stream.writeInt(mSamplerUniformRange.end);
    
        gl::Error error = mProgram->save(&stream);
        if (error.isError())
        {
            return error;
        }
    
        GLsizei streamLength   = static_cast<GLsizei>(stream.length());
        const void *streamData = stream.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.
            return Error(GL_INVALID_OPERATION);
        }
    
        if (binary)
        {
            char *ptr = reinterpret_cast<char*>(binary);
    
            memcpy(ptr, streamData, streamLength);
            ptr += streamLength;
    
            ASSERT(ptr - streamLength == binary);
        }
    
        if (length)
        {
            *length = streamLength;
        }
    
        return Error(GL_NO_ERROR);
    }
    
    GLint Program::getBinaryLength() const
    {
        GLint length;
        Error error = saveBinary(nullptr, nullptr, std::numeric_limits<GLint>::max(), &length);
        if (error.isError())
        {
            return 0;
        }
    
        return length;
    }
    
    void Program::setBinaryRetrievableHint(bool retrievable)
    {
        // TODO(jmadill) : replace with dirty bits
        mProgram->setBinaryRetrievableHint(retrievable);
        mData.mBinaryRetrieveableHint = retrievable;
    }
    
    bool Program::getBinaryRetrievableHint() const
    {
        return mData.mBinaryRetrieveableHint;
    }
    
    void Program::release()
    {
        mRefCount--;
    
        if (mRefCount == 0 && mDeleteStatus)
        {
            mResourceManager->deleteProgram(mHandle);
        }
    }
    
    void Program::addRef()
    {
        mRefCount++;
    }
    
    unsigned int Program::getRefCount() const
    {
        return mRefCount;
    }
    
    int Program::getInfoLogLength() const
    {
        return static_cast<int>(mInfoLog.getLength());
    }
    
    void Program::getInfoLog(GLsizei bufSize, GLsizei *length, char *infoLog) const
    {
        return mInfoLog.getLog(bufSize, length, infoLog);
    }
    
    void Program::getAttachedShaders(GLsizei maxCount, GLsizei *count, GLuint *shaders) const
    {
        int total = 0;
    
        if (mData.mAttachedVertexShader)
        {
            if (total < maxCount)
            {
                shaders[total] = mData.mAttachedVertexShader->getHandle();
            }
    
            total++;
        }
    
        if (mData.mAttachedFragmentShader)
        {
            if (total < maxCount)
            {
                shaders[total] = mData.mAttachedFragmentShader->getHandle();
            }
    
            total++;
        }
    
        if (count)
        {
            *count = total;
        }
    }
    
    GLuint Program::getAttributeLocation(const std::string &name) const
    {
        for (const sh::Attribute &attribute : mData.mAttributes)
        {
            if (attribute.name == name && attribute.staticUse)
            {
                return attribute.location;
            }
        }
    
        return static_cast<GLuint>(-1);
    }
    
    bool Program::isAttribLocationActive(size_t attribLocation) const
    {
        ASSERT(attribLocation < mData.mActiveAttribLocationsMask.size());
        return mData.mActiveAttribLocationsMask[attribLocation];
    }
    
    void Program::getActiveAttribute(GLuint index, GLsizei bufsize, GLsizei *length, GLint *size, GLenum *type, GLchar *name)
    {
        if (!mLinked)
        {
            if (bufsize > 0)
            {
                name[0] = '\0';
            }
    
            if (length)
            {
                *length = 0;
            }
    
            *type = GL_NONE;
            *size = 1;
            return;
        }
    
        size_t attributeIndex = 0;
    
        for (const sh::Attribute &attribute : mData.mAttributes)
        {
            // Skip over inactive attributes
            if (attribute.staticUse)
            {
                if (static_cast<size_t>(index) == attributeIndex)
                {
                    break;
                }
                attributeIndex++;
            }
        }
    
        ASSERT(index == attributeIndex && attributeIndex < mData.mAttributes.size());
        const sh::Attribute &attrib = mData.mAttributes[attributeIndex];
    
        if (bufsize > 0)
        {
            const char *string = attrib.name.c_str();
    
            strncpy(name, string, bufsize);
            name[bufsize - 1] = '\0';
    
            if (length)
            {
                *length = static_cast<GLsizei>(strlen(name));
            }
        }
    
        // Always a single 'type' instance
        *size = 1;
        *type = attrib.type;
    }
    
    GLint Program::getActiveAttributeCount() const
    {
        if (!mLinked)
        {
            return 0;
        }
    
        GLint count = 0;
    
        for (const sh::Attribute &attrib : mData.mAttributes)
        {
            count += (attrib.staticUse ? 1 : 0);
        }
    
        return count;
    }
    
    GLint Program::getActiveAttributeMaxLength() const
    {
        if (!mLinked)
        {
            return 0;
        }
    
        size_t maxLength = 0;
    
        for (const sh::Attribute &attrib : mData.mAttributes)
        {
            if (attrib.staticUse)
            {
                maxLength = std::max(attrib.name.length() + 1, maxLength);
            }
        }
    
        return static_cast<GLint>(maxLength);
    }
    
    GLint Program::getFragDataLocation(const std::string &name) const
    {
        std::string baseName(name);
        unsigned int arrayIndex = ParseAndStripArrayIndex(&baseName);
        for (auto outputPair : mData.mOutputVariables)
        {
            const VariableLocation &outputVariable = outputPair.second;
            if (outputVariable.name == baseName && (arrayIndex == GL_INVALID_INDEX || arrayIndex == outputVariable.element))
            {
                return static_cast<GLint>(outputPair.first);
            }
        }
        return -1;
    }
    
    void Program::getActiveUniform(GLuint index,
                                   GLsizei bufsize,
                                   GLsizei *length,
                                   GLint *size,
                                   GLenum *type,
                                   GLchar *name) const
    {
        if (mLinked)
        {
            // index must be smaller than getActiveUniformCount()
            ASSERT(index < mData.mUniforms.size());
            const LinkedUniform &uniform = mData.mUniforms[index];
    
            if (bufsize > 0)
            {
                std::string string = uniform.name;
                if (uniform.isArray())
                {
                    string += "[0]";
                }
    
                strncpy(name, string.c_str(), bufsize);
                name[bufsize - 1] = '\0';
    
                if (length)
                {
                    *length = static_cast<GLsizei>(strlen(name));
                }
            }
    
            *size = uniform.elementCount();
            *type = uniform.type;
        }
        else
        {
            if (bufsize > 0)
            {
                name[0] = '\0';
            }
    
            if (length)
            {
                *length = 0;
            }
    
            *size = 0;
            *type = GL_NONE;
        }
    }
    
    GLint Program::getActiveUniformCount() const
    {
        if (mLinked)
        {
            return static_cast<GLint>(mData.mUniforms.size());
        }
        else
        {
            return 0;
        }
    }
    
    GLint Program::getActiveUniformMaxLength() const
    {
        size_t maxLength = 0;
    
        if (mLinked)
        {
            for (const LinkedUniform &uniform : mData.mUniforms)
            {
                if (!uniform.name.empty())
                {
                    size_t length = uniform.name.length() + 1u;
                    if (uniform.isArray())
                    {
                        length += 3;  // Counting in "[0]".
                    }
                    maxLength = std::max(length, maxLength);
                }
            }
        }
    
        return static_cast<GLint>(maxLength);
    }
    
    GLint Program::getActiveUniformi(GLuint index, GLenum pname) const
    {
        ASSERT(static_cast<size_t>(index) < mData.mUniforms.size());
        const gl::LinkedUniform &uniform = mData.mUniforms[index];
        switch (pname)
        {
          case GL_UNIFORM_TYPE:         return static_cast<GLint>(uniform.type);
          case GL_UNIFORM_SIZE:         return static_cast<GLint>(uniform.elementCount());
          case GL_UNIFORM_NAME_LENGTH:  return static_cast<GLint>(uniform.name.size() + 1 + (uniform.isArray() ? 3 : 0));
          case GL_UNIFORM_BLOCK_INDEX:  return uniform.blockIndex;
          case GL_UNIFORM_OFFSET:       return uniform.blockInfo.offset;
          case GL_UNIFORM_ARRAY_STRIDE: return uniform.blockInfo.arrayStride;
          case GL_UNIFORM_MATRIX_STRIDE: return uniform.blockInfo.matrixStride;
          case GL_UNIFORM_IS_ROW_MAJOR: return static_cast<GLint>(uniform.blockInfo.isRowMajorMatrix);
          default:
            UNREACHABLE();
            break;
        }
        return 0;
    }
    
    bool Program::isValidUniformLocation(GLint location) const
    {
        ASSERT(rx::IsIntegerCastSafe<GLint>(mData.mUniformLocations.size()));
        return (location >= 0 && static_cast<size_t>(location) < mData.mUniformLocations.size());
    }
    
    const LinkedUniform &Program::getUniformByLocation(GLint location) const
    {
        ASSERT(location >= 0 && static_cast<size_t>(location) < mData.mUniformLocations.size());
        return mData.mUniforms[mData.mUniformLocations[location].index];
    }
    
    GLint Program::getUniformLocation(const std::string &name) const
    {
        return mData.getUniformLocation(name);
    }
    
    GLuint Program::getUniformIndex(const std::string &name) const
    {
        return mData.getUniformIndex(name);
    }
    
    void Program::setUniform1fv(GLint location, GLsizei count, const GLfloat *v)
    {
        setUniformInternal(location, count * 1, v);
        mProgram->setUniform1fv(location, count, v);
    }
    
    void Program::setUniform2fv(GLint location, GLsizei count, const GLfloat *v)
    {
        setUniformInternal(location, count * 2, v);
        mProgram->setUniform2fv(location, count, v);
    }
    
    void Program::setUniform3fv(GLint location, GLsizei count, const GLfloat *v)
    {
        setUniformInternal(location, count * 3, v);
        mProgram->setUniform3fv(location, count, v);
    }
    
    void Program::setUniform4fv(GLint location, GLsizei count, const GLfloat *v)
    {
        setUniformInternal(location, count * 4, v);
        mProgram->setUniform4fv(location, count, v);
    }
    
    void Program::setUniform1iv(GLint location, GLsizei count, const GLint *v)
    {
        setUniformInternal(location, count * 1, v);
        mProgram->setUniform1iv(location, count, v);
    }
    
    void Program::setUniform2iv(GLint location, GLsizei count, const GLint *v)
    {
        setUniformInternal(location, count * 2, v);
        mProgram->setUniform2iv(location, count, v);
    }
    
    void Program::setUniform3iv(GLint location, GLsizei count, const GLint *v)
    {
        setUniformInternal(location, count * 3, v);
        mProgram->setUniform3iv(location, count, v);
    }
    
    void Program::setUniform4iv(GLint location, GLsizei count, const GLint *v)
    {
        setUniformInternal(location, count * 4, v);
        mProgram->setUniform4iv(location, count, v);
    }
    
    void Program::setUniform1uiv(GLint location, GLsizei count, const GLuint *v)
    {
        setUniformInternal(location, count * 1, v);
        mProgram->setUniform1uiv(location, count, v);
    }
    
    void Program::setUniform2uiv(GLint location, GLsizei count, const GLuint *v)
    {
        setUniformInternal(location, count * 2, v);
        mProgram->setUniform2uiv(location, count, v);
    }
    
    void Program::setUniform3uiv(GLint location, GLsizei count, const GLuint *v)
    {
        setUniformInternal(location, count * 3, v);
        mProgram->setUniform3uiv(location, count, v);
    }
    
    void Program::setUniform4uiv(GLint location, GLsizei count, const GLuint *v)
    {
        setUniformInternal(location, count * 4, v);
        mProgram->setUniform4uiv(location, count, v);
    }
    
    void Program::setUniformMatrix2fv(GLint location, GLsizei count, GLboolean transpose, const GLfloat *v)
    {
        setMatrixUniformInternal<2, 2>(location, count, transpose, v);
        mProgram->setUniformMatrix2fv(location, count, transpose, v);
    }
    
    void Program::setUniformMatrix3fv(GLint location, GLsizei count, GLboolean transpose, const GLfloat *v)
    {
        setMatrixUniformInternal<3, 3>(location, count, transpose, v);
        mProgram->setUniformMatrix3fv(location, count, transpose, v);
    }
    
    void Program::setUniformMatrix4fv(GLint location, GLsizei count, GLboolean transpose, const GLfloat *v)
    {
        setMatrixUniformInternal<4, 4>(location, count, transpose, v);
        mProgram->setUniformMatrix4fv(location, count, transpose, v);
    }
    
    void Program::setUniformMatrix2x3fv(GLint location, GLsizei count, GLboolean transpose, const GLfloat *v)
    {
        setMatrixUniformInternal<2, 3>(location, count, transpose, v);
        mProgram->setUniformMatrix2x3fv(location, count, transpose, v);
    }
    
    void Program::setUniformMatrix2x4fv(GLint location, GLsizei count, GLboolean transpose, const GLfloat *v)
    {
        setMatrixUniformInternal<2, 4>(location, count, transpose, v);
        mProgram->setUniformMatrix2x4fv(location, count, transpose, v);
    }
    
    void Program::setUniformMatrix3x2fv(GLint location, GLsizei count, GLboolean transpose, const GLfloat *v)
    {
        setMatrixUniformInternal<3, 2>(location, count, transpose, v);
        mProgram->setUniformMatrix3x2fv(location, count, transpose, v);
    }
    
    void Program::setUniformMatrix3x4fv(GLint location, GLsizei count, GLboolean transpose, const GLfloat *v)
    {
        setMatrixUniformInternal<3, 4>(location, count, transpose, v);
        mProgram->setUniformMatrix3x4fv(location, count, transpose, v);
    }
    
    void Program::setUniformMatrix4x2fv(GLint location, GLsizei count, GLboolean transpose, const GLfloat *v)
    {
        setMatrixUniformInternal<4, 2>(location, count, transpose, v);
        mProgram->setUniformMatrix4x2fv(location, count, transpose, v);
    }
    
    void Program::setUniformMatrix4x3fv(GLint location, GLsizei count, GLboolean transpose, const GLfloat *v)
    {
        setMatrixUniformInternal<4, 3>(location, count, transpose, v);
        mProgram->setUniformMatrix4x3fv(location, count, transpose, v);
    }
    
    void Program::getUniformfv(GLint location, GLfloat *v) const
    {
        getUniformInternal(location, v);
    }
    
    void Program::getUniformiv(GLint location, GLint *v) const
    {
        getUniformInternal(location, v);
    }
    
    void Program::getUniformuiv(GLint location, GLuint *v) const
    {
        getUniformInternal(location, v);
    }
    
    void Program::flagForDeletion()
    {
        mDeleteStatus = true;
    }
    
    bool Program::isFlaggedForDeletion() const
    {
        return mDeleteStatus;
    }
    
    void Program::validate(const Caps &caps)
    {
        mInfoLog.reset();
    
        if (mLinked)
        {
            mValidated = (mProgram->validate(caps, &mInfoLog) == GL_TRUE);
        }
        else
        {
            mInfoLog << "Program has not been successfully linked.";
        }
    }
    
    bool Program::validateSamplers(InfoLog *infoLog, const Caps &caps)
    {
        // Skip cache if we're using an infolog, so we get the full error.
        // Also skip the cache if the sample mapping has changed, or if we haven't ever validated.
        if (infoLog == nullptr && mCachedValidateSamplersResult.valid())
        {
            return mCachedValidateSamplersResult.value();
        }
    
        if (mTextureUnitTypesCache.empty())
        {
            mTextureUnitTypesCache.resize(caps.maxCombinedTextureImageUnits, GL_NONE);
        }
        else
        {
            std::fill(mTextureUnitTypesCache.begin(), mTextureUnitTypesCache.end(), GL_NONE);
        }
    
        // if any two active samplers in a program are of different types, but refer to the same
        // texture image unit, and this is the current program, then ValidateProgram will fail, and
        // DrawArrays and DrawElements will issue the INVALID_OPERATION error.
        for (unsigned int samplerIndex = mSamplerUniformRange.start;
             samplerIndex < mSamplerUniformRange.end; ++samplerIndex)
        {
            const LinkedUniform &uniform = mData.mUniforms[samplerIndex];
            ASSERT(uniform.isSampler());
    
            if (!uniform.staticUse)
                continue;
    
            const GLuint *dataPtr = reinterpret_cast<const GLuint *>(uniform.getDataPtrToElement(0));
            GLenum textureType    = SamplerTypeToTextureType(uniform.type);
    
            for (unsigned int arrayElement = 0; arrayElement < uniform.elementCount(); ++arrayElement)
            {
                GLuint textureUnit = dataPtr[arrayElement];
    
                if (textureUnit >= caps.maxCombinedTextureImageUnits)
                {
                    if (infoLog)
                    {
                        (*infoLog) << "Sampler uniform (" << textureUnit
                                   << ") exceeds GL_MAX_COMBINED_TEXTURE_IMAGE_UNITS ("
                                   << caps.maxCombinedTextureImageUnits << ")";
                    }
    
                    mCachedValidateSamplersResult = false;
                    return false;
                }
    
                if (mTextureUnitTypesCache[textureUnit] != GL_NONE)
                {
                    if (textureType != mTextureUnitTypesCache[textureUnit])
                    {
                        if (infoLog)
                        {
                            (*infoLog) << "Samplers of conflicting types refer to the same texture "
                                          "image unit ("
                                       << textureUnit << ").";
                        }
    
                        mCachedValidateSamplersResult = false;
                        return false;
                    }
                }
                else
                {
                    mTextureUnitTypesCache[textureUnit] = textureType;
                }
            }
        }
    
        mCachedValidateSamplersResult = true;
        return true;
    }
    
    bool Program::isValidated() const
    {
        return mValidated;
    }
    
    GLuint Program::getActiveUniformBlockCount() const
    {
        return static_cast<GLuint>(mData.mUniformBlocks.size());
    }
    
    void Program::getActiveUniformBlockName(GLuint uniformBlockIndex, GLsizei bufSize, GLsizei *length, GLchar *uniformBlockName) const
    {
        ASSERT(uniformBlockIndex <
               mData.mUniformBlocks.size());  // index must be smaller than getActiveUniformBlockCount()
    
        const UniformBlock &uniformBlock = mData.mUniformBlocks[uniformBlockIndex];
    
        if (bufSize > 0)
        {
            std::string string = uniformBlock.name;
    
            if (uniformBlock.isArray)
            {
                string += ArrayString(uniformBlock.arrayElement);
            }
    
            strncpy(uniformBlockName, string.c_str(), bufSize);
            uniformBlockName[bufSize - 1] = '\0';
    
            if (length)
            {
                *length = static_cast<GLsizei>(strlen(uniformBlockName));
            }
        }
    }
    
    void Program::getActiveUniformBlockiv(GLuint uniformBlockIndex, GLenum pname, GLint *params) const
    {
        ASSERT(uniformBlockIndex <
               mData.mUniformBlocks.size());  // index must be smaller than getActiveUniformBlockCount()
    
        const UniformBlock &uniformBlock = mData.mUniformBlocks[uniformBlockIndex];
    
        switch (pname)
        {
          case GL_UNIFORM_BLOCK_DATA_SIZE:
            *params = static_cast<GLint>(uniformBlock.dataSize);
            break;
          case GL_UNIFORM_BLOCK_NAME_LENGTH:
              *params =
                  static_cast<GLint>(uniformBlock.name.size() + 1 + (uniformBlock.isArray ? 3 : 0));
            break;
          case GL_UNIFORM_BLOCK_ACTIVE_UNIFORMS:
            *params = static_cast<GLint>(uniformBlock.memberUniformIndexes.size());
            break;
          case GL_UNIFORM_BLOCK_ACTIVE_UNIFORM_INDICES:
            {
                for (unsigned int blockMemberIndex = 0; blockMemberIndex < uniformBlock.memberUniformIndexes.size(); blockMemberIndex++)
                {
                    params[blockMemberIndex] = static_cast<GLint>(uniformBlock.memberUniformIndexes[blockMemberIndex]);
                }
            }
            break;
          case GL_UNIFORM_BLOCK_REFERENCED_BY_VERTEX_SHADER:
              *params = static_cast<GLint>(uniformBlock.vertexStaticUse);
            break;
          case GL_UNIFORM_BLOCK_REFERENCED_BY_FRAGMENT_SHADER:
              *params = static_cast<GLint>(uniformBlock.fragmentStaticUse);
            break;
          default: UNREACHABLE();
        }
    }
    
    GLint Program::getActiveUniformBlockMaxLength() const
    {
        int maxLength = 0;
    
        if (mLinked)
        {
            unsigned int numUniformBlocks = static_cast<unsigned int>(mData.mUniformBlocks.size());
            for (unsigned int uniformBlockIndex = 0; uniformBlockIndex < numUniformBlocks; uniformBlockIndex++)
            {
                const UniformBlock &uniformBlock = mData.mUniformBlocks[uniformBlockIndex];
                if (!uniformBlock.name.empty())
                {
                    const int length = static_cast<int>(uniformBlock.name.length()) + 1;
    
                    // Counting in "[0]".
                    const int arrayLength = (uniformBlock.isArray ? 3 : 0);
    
                    maxLength = std::max(length + arrayLength, maxLength);
                }
            }
        }
    
        return maxLength;
    }
    
    GLuint Program::getUniformBlockIndex(const std::string &name) const
    {
        size_t subscript     = GL_INVALID_INDEX;
        std::string baseName = gl::ParseUniformName(name, &subscript);
    
        unsigned int numUniformBlocks = static_cast<unsigned int>(mData.mUniformBlocks.size());
        for (unsigned int blockIndex = 0; blockIndex < numUniformBlocks; blockIndex++)
        {
            const gl::UniformBlock &uniformBlock = mData.mUniformBlocks[blockIndex];
            if (uniformBlock.name == baseName)
            {
                const bool arrayElementZero =
                    (subscript == GL_INVALID_INDEX &&
                     (!uniformBlock.isArray || uniformBlock.arrayElement == 0));
                if (subscript == uniformBlock.arrayElement || arrayElementZero)
                {
                    return blockIndex;
                }
            }
        }
    
        return GL_INVALID_INDEX;
    }
    
    const UniformBlock &Program::getUniformBlockByIndex(GLuint index) const
    {
        ASSERT(index < static_cast<GLuint>(mData.mUniformBlocks.size()));
        return mData.mUniformBlocks[index];
    }
    
    void Program::bindUniformBlock(GLuint uniformBlockIndex, GLuint uniformBlockBinding)
    {
        mData.mUniformBlockBindings[uniformBlockIndex] = uniformBlockBinding;
        mProgram->setUniformBlockBinding(uniformBlockIndex, uniformBlockBinding);
    }
    
    GLuint Program::getUniformBlockBinding(GLuint uniformBlockIndex) const
    {
        return mData.getUniformBlockBinding(uniformBlockIndex);
    }
    
    void Program::resetUniformBlockBindings()
    {
        for (unsigned int blockId = 0; blockId < IMPLEMENTATION_MAX_COMBINED_SHADER_UNIFORM_BUFFERS; blockId++)
        {
            mData.mUniformBlockBindings[blockId] = 0;
        }
        mData.mActiveUniformBlockBindings.reset();
    }
    
    void Program::setTransformFeedbackVaryings(GLsizei count, const GLchar *const *varyings, GLenum bufferMode)
    {
        mData.mTransformFeedbackVaryingNames.resize(count);
        for (GLsizei i = 0; i < count; i++)
        {
            mData.mTransformFeedbackVaryingNames[i] = varyings[i];
        }
    
        mData.mTransformFeedbackBufferMode = bufferMode;
    }
    
    void Program::getTransformFeedbackVarying(GLuint index, GLsizei bufSize, GLsizei *length, GLsizei *size, GLenum *type, GLchar *name) const
    {
        if (mLinked)
        {
            ASSERT(index < mData.mTransformFeedbackVaryingVars.size());
            const sh::Varying &varying = mData.mTransformFeedbackVaryingVars[index];
            GLsizei lastNameIdx = std::min(bufSize - 1, static_cast<GLsizei>(varying.name.length()));
            if (length)
            {
                *length = lastNameIdx;
            }
            if (size)
            {
                *size = varying.elementCount();
            }
            if (type)
            {
                *type = varying.type;
            }
            if (name)
            {
                memcpy(name, varying.name.c_str(), lastNameIdx);
                name[lastNameIdx] = '\0';
            }
        }
    }
    
    GLsizei Program::getTransformFeedbackVaryingCount() const
    {
        if (mLinked)
        {
            return static_cast<GLsizei>(mData.mTransformFeedbackVaryingVars.size());
        }
        else
        {
            return 0;
        }
    }
    
    GLsizei Program::getTransformFeedbackVaryingMaxLength() const
    {
        if (mLinked)
        {
            GLsizei maxSize = 0;
            for (const sh::Varying &varying : mData.mTransformFeedbackVaryingVars)
            {
                maxSize = std::max(maxSize, static_cast<GLsizei>(varying.name.length() + 1));
            }
    
            return maxSize;
        }
        else
        {
            return 0;
        }
    }
    
    GLenum Program::getTransformFeedbackBufferMode() const
    {
        return mData.mTransformFeedbackBufferMode;
    }
    
    // static
    bool Program::linkVaryings(InfoLog &infoLog,
                               const Shader *vertexShader,
                               const Shader *fragmentShader)
    {
        const std::vector<sh::Varying> &vertexVaryings   = vertexShader->getVaryings();
        const std::vector<sh::Varying> &fragmentVaryings = fragmentShader->getVaryings();
    
        for (const sh::Varying &output : fragmentVaryings)
        {
            bool matched = false;
    
            // Built-in varyings obey special rules
            if (output.isBuiltIn())
            {
                continue;
            }
    
            for (const sh::Varying &input : vertexVaryings)
            {
                if (output.name == input.name)
                {
                    ASSERT(!input.isBuiltIn());
                    if (!linkValidateVaryings(infoLog, output.name, input, output))
                    {
                        return false;
                    }
    
                    matched = true;
                    break;
                }
            }
    
            // We permit unmatched, unreferenced varyings
            if (!matched && output.staticUse)
            {
                infoLog << "Fragment varying " << output.name << " does not match any vertex varying";
                return false;
            }
        }
    
        // TODO(jmadill): verify no unmatched vertex varyings?
    
        return true;
    }
    
    bool Program::linkUniforms(gl::InfoLog &infoLog, const gl::Caps &caps)
    {
        const std::vector<sh::Uniform> &vertexUniforms   = mData.mAttachedVertexShader->getUniforms();
        const std::vector<sh::Uniform> &fragmentUniforms = mData.mAttachedFragmentShader->getUniforms();
    
        // Check that uniforms defined in the vertex and fragment shaders are identical
        std::map<std::string, LinkedUniform> linkedUniforms;
    
        for (const sh::Uniform &vertexUniform : vertexUniforms)
        {
            linkedUniforms[vertexUniform.name] = LinkedUniform(vertexUniform);
        }
    
        for (const sh::Uniform &fragmentUniform : fragmentUniforms)
        {
            auto entry = linkedUniforms.find(fragmentUniform.name);
            if (entry != linkedUniforms.end())
            {
                LinkedUniform *vertexUniform   = &entry->second;
                const std::string &uniformName = "uniform '" + vertexUniform->name + "'";
                if (!linkValidateUniforms(infoLog, uniformName, *vertexUniform, fragmentUniform))
                {
                    return false;
                }
            }
        }
    
        // Flatten the uniforms list (nested fields) into a simple list (no nesting).
        // Also check the maximum uniform vector and sampler counts.
        if (!flattenUniformsAndCheckCaps(caps, infoLog))
        {
            return false;
        }
    
        indexUniforms();
    
        return true;
    }
    
    void Program::indexUniforms()
    {
        for (size_t uniformIndex = 0; uniformIndex < mData.mUniforms.size(); uniformIndex++)
        {
            const gl::LinkedUniform &uniform = mData.mUniforms[uniformIndex];
    
            for (unsigned int arrayIndex = 0; arrayIndex < uniform.elementCount(); arrayIndex++)
            {
                if (!uniform.isBuiltIn())
                {
                    // Assign in-order uniform locations
                    mData.mUniformLocations.push_back(gl::VariableLocation(
                        uniform.name, arrayIndex, static_cast<unsigned int>(uniformIndex)));
                }
            }
        }
    }
    
    bool Program::linkValidateInterfaceBlockFields(InfoLog &infoLog, const std::string &uniformName, const sh::InterfaceBlockField &vertexUniform, const sh::InterfaceBlockField &fragmentUniform)
    {
        // We don't validate precision on UBO fields. See resolution of Khronos bug 10287.
        if (!linkValidateVariablesBase(infoLog, uniformName, vertexUniform, fragmentUniform, false))
        {
            return false;
        }
    
        if (vertexUniform.isRowMajorLayout != fragmentUniform.isRowMajorLayout)
        {
            infoLog << "Matrix packings for " << uniformName << " differ between vertex and fragment shaders";
            return false;
        }
    
        return true;
    }
    
    // Determines the mapping between GL attributes and Direct3D 9 vertex stream usage indices
    bool Program::linkAttributes(const gl::Data &data,
                                 InfoLog &infoLog,
                                 const AttributeBindings &attributeBindings,
                                 const Shader *vertexShader)
    {
        unsigned int usedLocations = 0;
        mData.mAttributes          = vertexShader->getActiveAttributes();
        GLuint maxAttribs = data.caps->maxVertexAttributes;
    
        // TODO(jmadill): handle aliasing robustly
        if (mData.mAttributes.size() > maxAttribs)
        {
            infoLog << "Too many vertex attributes.";
            return false;
        }
    
        std::vector<sh::Attribute *> usedAttribMap(data.caps->maxVertexAttributes, nullptr);
    
        // Link attributes that have a binding location
        for (sh::Attribute &attribute : mData.mAttributes)
        {
            // TODO(jmadill): do staticUse filtering step here, or not at all
            ASSERT(attribute.staticUse);
    
            int bindingLocation = attributeBindings.getAttributeBinding(attribute.name);
            if (attribute.location == -1 && bindingLocation != -1)
            {
                attribute.location = bindingLocation;
            }
    
            if (attribute.location != -1)
            {
                // Location is set by glBindAttribLocation or by location layout qualifier
                const int regs = VariableRegisterCount(attribute.type);
    
                if (static_cast<GLuint>(regs + attribute.location) > maxAttribs)
                {
                    infoLog << "Active attribute (" << attribute.name << ") at location "
                            << attribute.location << " is too big to fit";
    
                    return false;
                }
    
                for (int reg = 0; reg < regs; reg++)
                {
                    const int regLocation               = attribute.location + reg;
                    sh::ShaderVariable *linkedAttribute = usedAttribMap[regLocation];
    
                    // In GLSL 3.00, attribute aliasing produces a link error
                    // In GLSL 1.00, attribute aliasing is allowed, but ANGLE currently has a bug
                    if (linkedAttribute)
                    {
                        // TODO(jmadill): fix aliasing on ES2
                        // if (mProgram->getShaderVersion() >= 300)
                        {
                            infoLog << "Attribute '" << attribute.name << "' aliases attribute '"
                                    << linkedAttribute->name << "' at location " << regLocation;
                            return false;
                        }
                    }
                    else
                    {
                        usedAttribMap[regLocation] = &attribute;
                    }
    
                    usedLocations |= 1 << regLocation;
                }
            }
        }
    
        // Link attributes that don't have a binding location
        for (sh::Attribute &attribute : mData.mAttributes)
        {
            ASSERT(attribute.staticUse);
    
            // Not set by glBindAttribLocation or by location layout qualifier
            if (attribute.location == -1)
            {
                int regs           = VariableRegisterCount(attribute.type);
                int availableIndex = AllocateFirstFreeBits(&usedLocations, regs, maxAttribs);
    
                if (availableIndex == -1 || static_cast<GLuint>(availableIndex + regs) > maxAttribs)
                {
                    infoLog << "Too many active attributes (" << attribute.name << ")";
                    return false;
                }
    
                attribute.location = availableIndex;
            }
        }
    
        for (const sh::Attribute &attribute : mData.mAttributes)
        {
            ASSERT(attribute.staticUse);
            ASSERT(attribute.location != -1);
            int regs = VariableRegisterCount(attribute.type);
    
            for (int r = 0; r < regs; r++)
            {
                mData.mActiveAttribLocationsMask.set(attribute.location + r);
            }
        }
    
        return true;
    }
    
    bool Program::linkUniformBlocks(InfoLog &infoLog, const Caps &caps)
    {
        const Shader &vertexShader   = *mData.mAttachedVertexShader;
        const Shader &fragmentShader = *mData.mAttachedFragmentShader;
    
        const std::vector<sh::InterfaceBlock> &vertexInterfaceBlocks = vertexShader.getInterfaceBlocks();
        const std::vector<sh::InterfaceBlock> &fragmentInterfaceBlocks = fragmentShader.getInterfaceBlocks();
    
        // Check that interface blocks defined in the vertex and fragment shaders are identical
        typedef std::map<std::string, const sh::InterfaceBlock*> UniformBlockMap;
        UniformBlockMap linkedUniformBlocks;
    
        GLuint vertexBlockCount = 0;
        for (const sh::InterfaceBlock &vertexInterfaceBlock : vertexInterfaceBlocks)
        {
            linkedUniformBlocks[vertexInterfaceBlock.name] = &vertexInterfaceBlock;
    
            // Note: shared and std140 layouts are always considered active
            if (vertexInterfaceBlock.staticUse || vertexInterfaceBlock.layout != sh::BLOCKLAYOUT_PACKED)
            {
                if (++vertexBlockCount > caps.maxVertexUniformBlocks)
                {
                    infoLog << "Vertex shader uniform block count exceed GL_MAX_VERTEX_UNIFORM_BLOCKS ("
                            << caps.maxVertexUniformBlocks << ")";
                    return false;
                }
            }
        }
    
        GLuint fragmentBlockCount = 0;
        for (const sh::InterfaceBlock &fragmentInterfaceBlock : fragmentInterfaceBlocks)
        {
            auto entry = linkedUniformBlocks.find(fragmentInterfaceBlock.name);
            if (entry != linkedUniformBlocks.end())
            {
                const sh::InterfaceBlock &vertexInterfaceBlock = *entry->second;
                if (!areMatchingInterfaceBlocks(infoLog, vertexInterfaceBlock, fragmentInterfaceBlock))
                {
                    return false;
                }
            }
    
            // Note: shared and std140 layouts are always considered active
            if (fragmentInterfaceBlock.staticUse ||
                fragmentInterfaceBlock.layout != sh::BLOCKLAYOUT_PACKED)
            {
                if (++fragmentBlockCount > caps.maxFragmentUniformBlocks)
                {
                    infoLog
                        << "Fragment shader uniform block count exceed GL_MAX_FRAGMENT_UNIFORM_BLOCKS ("
                        << caps.maxFragmentUniformBlocks << ")";
                    return false;
                }
            }
        }
    
        return true;
    }
    
    bool Program::areMatchingInterfaceBlocks(gl::InfoLog &infoLog, const sh::InterfaceBlock &vertexInterfaceBlock,
                                             const sh::InterfaceBlock &fragmentInterfaceBlock)
    {
        const char* blockName = vertexInterfaceBlock.name.c_str();
        // validate blocks for the same member types
        if (vertexInterfaceBlock.fields.size() != fragmentInterfaceBlock.fields.size())
        {
            infoLog << "Types for interface block '" << blockName
                    << "' differ between vertex and fragment shaders";
            return false;
        }
        if (vertexInterfaceBlock.arraySize != fragmentInterfaceBlock.arraySize)
        {
            infoLog << "Array sizes differ for interface block '" << blockName
                    << "' between vertex and fragment shaders";
            return false;
        }
        if (vertexInterfaceBlock.layout != fragmentInterfaceBlock.layout || vertexInterfaceBlock.isRowMajorLayout != fragmentInterfaceBlock.isRowMajorLayout)
        {
            infoLog << "Layout qualifiers differ for interface block '" << blockName
                    << "' between vertex and fragment shaders";
            return false;
        }
        const unsigned int numBlockMembers =
            static_cast<unsigned int>(vertexInterfaceBlock.fields.size());
        for (unsigned int blockMemberIndex = 0; blockMemberIndex < numBlockMembers; blockMemberIndex++)
        {
            const sh::InterfaceBlockField &vertexMember = vertexInterfaceBlock.fields[blockMemberIndex];
            const sh::InterfaceBlockField &fragmentMember = fragmentInterfaceBlock.fields[blockMemberIndex];
            if (vertexMember.name != fragmentMember.name)
            {
                infoLog << "Name mismatch for field " << blockMemberIndex
                        << " of interface block '" << blockName
                        << "': (in vertex: '" << vertexMember.name
                        << "', in fragment: '" << fragmentMember.name << "')";
                return false;
            }
            std::string memberName = "interface block '" + vertexInterfaceBlock.name + "' member '" + vertexMember.name + "'";
            if (!linkValidateInterfaceBlockFields(infoLog, memberName, vertexMember, fragmentMember))
            {
                return false;
            }
        }
        return true;
    }
    
    bool Program::linkValidateVariablesBase(InfoLog &infoLog, const std::string &variableName, const sh::ShaderVariable &vertexVariable,
                                                  const sh::ShaderVariable &fragmentVariable, bool validatePrecision)
    {
        if (vertexVariable.type != fragmentVariable.type)
        {
            infoLog << "Types for " << variableName << " differ between vertex and fragment shaders";
            return false;
        }
        if (vertexVariable.arraySize != fragmentVariable.arraySize)
        {
            infoLog << "Array sizes for " << variableName << " differ between vertex and fragment shaders";
            return false;
        }
        if (validatePrecision && vertexVariable.precision != fragmentVariable.precision)
        {
            infoLog << "Precisions for " << variableName << " differ between vertex and fragment shaders";
            return false;
        }
    
        if (vertexVariable.fields.size() != fragmentVariable.fields.size())
        {
            infoLog << "Structure lengths for " << variableName << " differ between vertex and fragment shaders";
            return false;
        }
        const unsigned int numMembers = static_cast<unsigned int>(vertexVariable.fields.size());
        for (unsigned int memberIndex = 0; memberIndex < numMembers; memberIndex++)
        {
            const sh::ShaderVariable &vertexMember = vertexVariable.fields[memberIndex];
            const sh::ShaderVariable &fragmentMember = fragmentVariable.fields[memberIndex];
    
            if (vertexMember.name != fragmentMember.name)
            {
                infoLog << "Name mismatch for field '" << memberIndex
                        << "' of " << variableName
                        << ": (in vertex: '" << vertexMember.name
                        << "', in fragment: '" << fragmentMember.name << "')";
                return false;
            }
    
            const std::string memberName = variableName.substr(0, variableName.length() - 1) + "." +
                                           vertexMember.name + "'";
    
            if (!linkValidateVariablesBase(infoLog, vertexMember.name, vertexMember, fragmentMember, validatePrecision))
            {
                return false;
            }
        }
    
        return true;
    }
    
    bool Program::linkValidateUniforms(InfoLog &infoLog, const std::string &uniformName, const sh::Uniform &vertexUniform, const sh::Uniform &fragmentUniform)
    {
    #if ANGLE_PROGRAM_LINK_VALIDATE_UNIFORM_PRECISION == ANGLE_ENABLED
        const bool validatePrecision = true;
    #else
        const bool validatePrecision = false;
    #endif
    
        if (!linkValidateVariablesBase(infoLog, uniformName, vertexUniform, fragmentUniform, validatePrecision))
        {
            return false;
        }
    
        return true;
    }
    
    bool Program::linkValidateVaryings(InfoLog &infoLog, const std::string &varyingName, const sh::Varying &vertexVarying, const sh::Varying &fragmentVarying)
    {
        if (!linkValidateVariablesBase(infoLog, varyingName, vertexVarying, fragmentVarying, false))
        {
            return false;
        }
    
        if (!sh::InterpolationTypesMatch(vertexVarying.interpolation, fragmentVarying.interpolation))
        {
            infoLog << "Interpolation types for " << varyingName << " differ between vertex and fragment shaders";
            return false;
        }
    
        return true;
    }
    
    bool Program::linkValidateTransformFeedback(InfoLog &infoLog,
                                                const std::vector<const sh::Varying *> &varyings,
                                                const Caps &caps) const
    {
        size_t totalComponents = 0;
    
        std::set<std::string> uniqueNames;
    
        for (const std::string &tfVaryingName : mData.mTransformFeedbackVaryingNames)
        {
            bool found = false;
            for (const sh::Varying *varying : varyings)
            {
                if (tfVaryingName == varying->name)
                {
                    if (uniqueNames.count(tfVaryingName) > 0)
                    {
                        infoLog << "Two transform feedback varyings specify the same output variable ("
                                << tfVaryingName << ").";
                        return false;
                    }
                    uniqueNames.insert(tfVaryingName);
    
                    if (varying->isArray())
                    {
                        infoLog << "Capture of arrays is undefined and not supported.";
                        return false;
                    }
    
                    // TODO(jmadill): Investigate implementation limits on D3D11
                    size_t componentCount = gl::VariableComponentCount(varying->type);
                    if (mData.mTransformFeedbackBufferMode == GL_SEPARATE_ATTRIBS &&
                        componentCount > caps.maxTransformFeedbackSeparateComponents)
                    {
                        infoLog << "Transform feedback varying's " << varying->name << " components ("
                                << componentCount << ") exceed the maximum separate components ("
                                << caps.maxTransformFeedbackSeparateComponents << ").";
                        return false;
                    }
    
                    totalComponents += componentCount;
                    found = true;
                    break;
                }
            }
    
            if (tfVaryingName.find('[') != std::string::npos)
            {
                infoLog << "Capture of array elements is undefined and not supported.";
                return false;
            }
    
            // All transform feedback varyings are expected to exist since packVaryings checks for them.
            ASSERT(found);
            UNUSED_ASSERTION_VARIABLE(found);
        }
    
        if (mData.mTransformFeedbackBufferMode == GL_INTERLEAVED_ATTRIBS &&
            totalComponents > caps.maxTransformFeedbackInterleavedComponents)
        {
            infoLog << "Transform feedback varying total components (" << totalComponents
                    << ") exceed the maximum interleaved components ("
                    << caps.maxTransformFeedbackInterleavedComponents << ").";
            return false;
        }
    
        return true;
    }
    
    void Program::gatherTransformFeedbackVaryings(const std::vector<const sh::Varying *> &varyings)
    {
        // Gather the linked varyings that are used for transform feedback, they should all exist.
        mData.mTransformFeedbackVaryingVars.clear();
        for (const std::string &tfVaryingName : mData.mTransformFeedbackVaryingNames)
        {
            for (const sh::Varying *varying : varyings)
            {
                if (tfVaryingName == varying->name)
                {
                    mData.mTransformFeedbackVaryingVars.push_back(*varying);
                    break;
                }
            }
        }
    }
    
    std::vector<const sh::Varying *> Program::getMergedVaryings() const
    {
        std::set<std::string> uniqueNames;
        std::vector<const sh::Varying *> varyings;
    
        for (const sh::Varying &varying : mData.mAttachedVertexShader->getVaryings())
        {
            if (uniqueNames.count(varying.name) == 0)
            {
                uniqueNames.insert(varying.name);
                varyings.push_back(&varying);
            }
        }
    
        for (const sh::Varying &varying : mData.mAttachedFragmentShader->getVaryings())
        {
            if (uniqueNames.count(varying.name) == 0)
            {
                uniqueNames.insert(varying.name);
                varyings.push_back(&varying);
            }
        }
    
        return varyings;
    }
    
    void Program::linkOutputVariables()
    {
        const Shader *fragmentShader = mData.mAttachedFragmentShader;
        ASSERT(fragmentShader != nullptr);
    
        // Skip this step for GLES2 shaders.
        if (fragmentShader->getShaderVersion() == 100)
            return;
    
        const auto &shaderOutputVars = fragmentShader->getActiveOutputVariables();
    
        // TODO(jmadill): any caps validation here?
    
        for (unsigned int outputVariableIndex = 0; outputVariableIndex < shaderOutputVars.size();
             outputVariableIndex++)
        {
            const sh::OutputVariable &outputVariable = shaderOutputVars[outputVariableIndex];
    
            // Don't store outputs for gl_FragDepth, gl_FragColor, etc.
            if (outputVariable.isBuiltIn())
                continue;
    
            // Since multiple output locations must be specified, use 0 for non-specified locations.
            int baseLocation = (outputVariable.location == -1 ? 0 : outputVariable.location);
    
            ASSERT(outputVariable.staticUse);
    
            for (unsigned int elementIndex = 0; elementIndex < outputVariable.elementCount();
                 elementIndex++)
            {
                const int location = baseLocation + elementIndex;
                ASSERT(mData.mOutputVariables.count(location) == 0);
                unsigned int element = outputVariable.isArray() ? elementIndex : GL_INVALID_INDEX;
                mData.mOutputVariables[location] =
                    VariableLocation(outputVariable.name, element, outputVariableIndex);
            }
        }
    }
    
    bool Program::flattenUniformsAndCheckCaps(const Caps &caps, InfoLog &infoLog)
    {
        const gl::Shader *vertexShader = mData.getAttachedVertexShader();
        VectorAndSamplerCount vsCounts;
    
        std::vector<LinkedUniform> samplerUniforms;
    
        for (const sh::Uniform &uniform : vertexShader->getUniforms())
        {
            if (uniform.staticUse)
            {
                vsCounts += flattenUniform(uniform, uniform.name, &samplerUniforms);
            }
        }
    
        if (vsCounts.vectorCount > caps.maxVertexUniformVectors)
        {
            infoLog << "Vertex shader active uniforms exceed MAX_VERTEX_UNIFORM_VECTORS ("
                    << caps.maxVertexUniformVectors << ").";
            return false;
        }
    
        if (vsCounts.samplerCount > caps.maxVertexTextureImageUnits)
        {
            infoLog << "Vertex shader sampler count exceeds MAX_VERTEX_TEXTURE_IMAGE_UNITS ("
                    << caps.maxVertexTextureImageUnits << ").";
            return false;
        }
    
        const gl::Shader *fragmentShader = mData.getAttachedFragmentShader();
        VectorAndSamplerCount fsCounts;
    
        for (const sh::Uniform &uniform : fragmentShader->getUniforms())
        {
            if (uniform.staticUse)
            {
                fsCounts += flattenUniform(uniform, uniform.name, &samplerUniforms);
            }
        }
    
        if (fsCounts.vectorCount > caps.maxFragmentUniformVectors)
        {
            infoLog << "Fragment shader active uniforms exceed MAX_FRAGMENT_UNIFORM_VECTORS ("
                    << caps.maxFragmentUniformVectors << ").";
            return false;
        }
    
        if (fsCounts.samplerCount > caps.maxTextureImageUnits)
        {
            infoLog << "Fragment shader sampler count exceeds MAX_TEXTURE_IMAGE_UNITS ("
                    << caps.maxTextureImageUnits << ").";
            return false;
        }
    
        mSamplerUniformRange.start = static_cast<unsigned int>(mData.mUniforms.size());
        mSamplerUniformRange.end =
            mSamplerUniformRange.start + static_cast<unsigned int>(samplerUniforms.size());
    
        mData.mUniforms.insert(mData.mUniforms.end(), samplerUniforms.begin(), samplerUniforms.end());
    
        return true;
    }
    
    Program::VectorAndSamplerCount Program::flattenUniform(const sh::ShaderVariable &uniform,
                                                           const std::string &fullName,
                                                           std::vector<LinkedUniform> *samplerUniforms)
    {
        VectorAndSamplerCount vectorAndSamplerCount;
    
        if (uniform.isStruct())
        {
            for (unsigned int elementIndex = 0; elementIndex < uniform.elementCount(); elementIndex++)
            {
                const std::string &elementString = (uniform.isArray() ? ArrayString(elementIndex) : "");
    
                for (size_t fieldIndex = 0; fieldIndex < uniform.fields.size(); fieldIndex++)
                {
                    const sh::ShaderVariable &field  = uniform.fields[fieldIndex];
                    const std::string &fieldFullName = (fullName + elementString + "." + field.name);
    
                    vectorAndSamplerCount += flattenUniform(field, fieldFullName, samplerUniforms);
                }
            }
    
            return vectorAndSamplerCount;
        }
    
        // Not a struct
        bool isSampler = IsSamplerType(uniform.type);
        if (!UniformInList(mData.getUniforms(), fullName) && !UniformInList(*samplerUniforms, fullName))
        {
            gl::LinkedUniform linkedUniform(uniform.type, uniform.precision, fullName,
                                            uniform.arraySize, -1,
                                            sh::BlockMemberInfo::getDefaultBlockInfo());
            linkedUniform.staticUse = true;
    
            // Store sampler uniforms separately, so we'll append them to the end of the list.
            if (isSampler)
            {
                samplerUniforms->push_back(linkedUniform);
            }
            else
            {
                mData.mUniforms.push_back(linkedUniform);
            }
        }
    
        unsigned int elementCount          = uniform.elementCount();
    
        // Samplers aren't "real" uniforms, so they don't count towards register usage.
        // Likewise, don't count "real" uniforms towards sampler count.
        vectorAndSamplerCount.vectorCount =
            (isSampler ? 0 : (VariableRegisterCount(uniform.type) * elementCount));
        vectorAndSamplerCount.samplerCount = (isSampler ? elementCount : 0);
    
        return vectorAndSamplerCount;
    }
    
    void Program::gatherInterfaceBlockInfo()
    {
        std::set<std::string> visitedList;
    
        const gl::Shader *vertexShader = mData.getAttachedVertexShader();
    
        ASSERT(mData.mUniformBlocks.empty());
        for (const sh::InterfaceBlock &vertexBlock : vertexShader->getInterfaceBlocks())
        {
            // Only 'packed' blocks are allowed to be considered inacive.
            if (!vertexBlock.staticUse && vertexBlock.layout == sh::BLOCKLAYOUT_PACKED)
                continue;
    
            if (visitedList.count(vertexBlock.name) > 0)
                continue;
    
            defineUniformBlock(vertexBlock, GL_VERTEX_SHADER);
            visitedList.insert(vertexBlock.name);
        }
    
        const gl::Shader *fragmentShader = mData.getAttachedFragmentShader();
    
        for (const sh::InterfaceBlock &fragmentBlock : fragmentShader->getInterfaceBlocks())
        {
            // Only 'packed' blocks are allowed to be considered inacive.
            if (!fragmentBlock.staticUse && fragmentBlock.layout == sh::BLOCKLAYOUT_PACKED)
                continue;
    
            if (visitedList.count(fragmentBlock.name) > 0)
            {
                for (gl::UniformBlock &block : mData.mUniformBlocks)
                {
                    if (block.name == fragmentBlock.name)
                    {
                        block.fragmentStaticUse = fragmentBlock.staticUse;
                    }
                }
    
                continue;
            }
    
            defineUniformBlock(fragmentBlock, GL_FRAGMENT_SHADER);
            visitedList.insert(fragmentBlock.name);
        }
    }
    
    template <typename VarT>
    void Program::defineUniformBlockMembers(const std::vector<VarT> &fields,
                                            const std::string &prefix,
                                            int blockIndex)
    {
        for (const VarT &field : fields)
        {
            const std::string &fullName = (prefix.empty() ? field.name : prefix + "." + field.name);
    
            if (field.isStruct())
            {
                for (unsigned int arrayElement = 0; arrayElement < field.elementCount(); arrayElement++)
                {
                    const std::string uniformElementName =
                        fullName + (field.isArray() ? ArrayString(arrayElement) : "");
                    defineUniformBlockMembers(field.fields, uniformElementName, blockIndex);
                }
            }
            else
            {
                // If getBlockMemberInfo returns false, the uniform is optimized out.
                sh::BlockMemberInfo memberInfo;
                if (!mProgram->getUniformBlockMemberInfo(fullName, &memberInfo))
                {
                    continue;
                }
    
                LinkedUniform newUniform(field.type, field.precision, fullName, field.arraySize,
                                         blockIndex, memberInfo);
    
                // Since block uniforms have no location, we don't need to store them in the uniform
                // locations list.
                mData.mUniforms.push_back(newUniform);
            }
        }
    }
    
    void Program::defineUniformBlock(const sh::InterfaceBlock &interfaceBlock, GLenum shaderType)
    {
        int blockIndex   = static_cast<int>(mData.mUniformBlocks.size());
        size_t blockSize = 0;
    
        // Don't define this block at all if it's not active in the implementation.
        if (!mProgram->getUniformBlockSize(interfaceBlock.name, &blockSize))
        {
            return;
        }
    
        // Track the first and last uniform index to determine the range of active uniforms in the
        // block.
        size_t firstBlockUniformIndex = mData.mUniforms.size();
        defineUniformBlockMembers(interfaceBlock.fields, "", blockIndex);
        size_t lastBlockUniformIndex = mData.mUniforms.size();
    
        std::vector<unsigned int> blockUniformIndexes;
        for (size_t blockUniformIndex = firstBlockUniformIndex;
             blockUniformIndex < lastBlockUniformIndex; ++blockUniformIndex)
        {
            blockUniformIndexes.push_back(static_cast<unsigned int>(blockUniformIndex));
        }
    
        if (interfaceBlock.arraySize > 0)
        {
            for (unsigned int arrayElement = 0; arrayElement < interfaceBlock.arraySize; ++arrayElement)
            {
                UniformBlock block(interfaceBlock.name, true, arrayElement);
                block.memberUniformIndexes = blockUniformIndexes;
    
                if (shaderType == GL_VERTEX_SHADER)
                {
                    block.vertexStaticUse = interfaceBlock.staticUse;
                }
                else
                {
                    ASSERT(shaderType == GL_FRAGMENT_SHADER);
                    block.fragmentStaticUse = interfaceBlock.staticUse;
                }
    
                // TODO(jmadill): Determine if we can ever have an inactive array element block.
                size_t blockElementSize = 0;
                if (!mProgram->getUniformBlockSize(block.nameWithArrayIndex(), &blockElementSize))
                {
                    continue;
                }
    
                ASSERT(blockElementSize == blockSize);
                block.dataSize = static_cast<unsigned int>(blockElementSize);
                mData.mUniformBlocks.push_back(block);
            }
        }
        else
        {
            UniformBlock block(interfaceBlock.name, false, 0);
            block.memberUniformIndexes = blockUniformIndexes;
    
            if (shaderType == GL_VERTEX_SHADER)
            {
                block.vertexStaticUse = interfaceBlock.staticUse;
            }
            else
            {
                ASSERT(shaderType == GL_FRAGMENT_SHADER);
                block.fragmentStaticUse = interfaceBlock.staticUse;
            }
    
            block.dataSize = static_cast<unsigned int>(blockSize);
            mData.mUniformBlocks.push_back(block);
        }
    }
    
    template <typename T>
    void Program::setUniformInternal(GLint location, GLsizei count, const T *v)
    {
        const VariableLocation &locationInfo = mData.mUniformLocations[location];
        LinkedUniform *linkedUniform         = &mData.mUniforms[locationInfo.index];
        uint8_t *destPointer                 = linkedUniform->getDataPtrToElement(locationInfo.element);
    
        if (VariableComponentType(linkedUniform->type) == GL_BOOL)
        {
            // Do a cast conversion for boolean types. From the spec:
            // "The uniform is set to FALSE if the input value is 0 or 0.0f, and set to TRUE otherwise."
            GLint *destAsInt = reinterpret_cast<GLint *>(destPointer);
            for (GLsizei component = 0; component < count; ++component)
            {
                destAsInt[component] = (v[component] != static_cast<T>(0) ? GL_TRUE : GL_FALSE);
            }
        }
        else
        {
            // Invalide the validation cache if we modify the sampler data.
            if (linkedUniform->isSampler() && memcmp(destPointer, v, sizeof(T) * count) != 0)
            {
                mCachedValidateSamplersResult.reset();
            }
    
            memcpy(destPointer, v, sizeof(T) * count);
        }
    }
    
    template <size_t cols, size_t rows, typename T>
    void Program::setMatrixUniformInternal(GLint location,
                                           GLsizei count,
                                           GLboolean transpose,
                                           const T *v)
    {
        if (!transpose)
        {
            setUniformInternal(location, count * cols * rows, v);
            return;
        }
    
        // Perform a transposing copy.
        const VariableLocation &locationInfo = mData.mUniformLocations[location];
        LinkedUniform *linkedUniform         = &mData.mUniforms[locationInfo.index];
        T *destPtr = reinterpret_cast<T *>(linkedUniform->getDataPtrToElement(locationInfo.element));
        for (GLsizei element = 0; element < count; ++element)
        {
            size_t elementOffset = element * rows * cols;
    
            for (size_t row = 0; row < rows; ++row)
            {
                for (size_t col = 0; col < cols; ++col)
                {
                    destPtr[col * rows + row + elementOffset] = v[row * cols + col + elementOffset];
                }
            }
        }
    }
    
    template <typename DestT>
    void Program::getUniformInternal(GLint location, DestT *dataOut) const
    {
        const VariableLocation &locationInfo = mData.mUniformLocations[location];
        const LinkedUniform &uniform         = mData.mUniforms[locationInfo.index];
    
        const uint8_t *srcPointer = uniform.getDataPtrToElement(locationInfo.element);
    
        GLenum componentType = VariableComponentType(uniform.type);
        if (componentType == GLTypeToGLenum<DestT>::value)
        {
            memcpy(dataOut, srcPointer, uniform.getElementSize());
            return;
        }
    
        int components = VariableComponentCount(uniform.type) * uniform.elementCount();
    
        switch (componentType)
        {
            case GL_INT:
                UniformStateQueryCastLoop<GLint>(dataOut, srcPointer, components);
                break;
            case GL_UNSIGNED_INT:
                UniformStateQueryCastLoop<GLuint>(dataOut, srcPointer, components);
                break;
            case GL_BOOL:
                UniformStateQueryCastLoop<GLboolean>(dataOut, srcPointer, components);
                break;
            case GL_FLOAT:
                UniformStateQueryCastLoop<GLfloat>(dataOut, srcPointer, components);
                break;
            default:
                UNREACHABLE();
        }
    }
    }