IntermNode.cpp

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Author : Olli Etuaho
Date : 2017-10-11 12:01:38
Hash : 923ecef6
Message : Fix switch statement validation corner cases The grammar needs to generate AST nodes even for no-op statements, since they might be the last statement in a switch statement that is required for switch statement validity. Change the grammar to generate nodes from empty blocks and empty declarations. We also need to do some further processing of the AST. This is because PruneEmptyDeclarations will still remove empty declarations, and at least the NVIDIA driver GLSL compiler doesn't accept some types of no-op statements as the last statement inside a switch statement. So after parsing has finished we do rudimentary dead code elimination to remove dead cases from the end of switch statements. BUG=angleproject:2181 TEST=angle_unittests Change-Id: I586f2e4a3ac2171e65f1f0ccb7a7de220e3cc225 Reviewed-on: https://chromium-review.googlesource.com/712574 Commit-Queue: Olli Etuaho <oetuaho@nvidia.com> Reviewed-by: Corentin Wallez <cwallez@chromium.org>
src/compiler/translator/IntermNode.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.
//

//
// Build the intermediate representation.
//

#include <float.h>
#include <limits.h>
#include <math.h>
#include <stdlib.h>
#include <algorithm>
#include <vector>

#include "common/mathutil.h"
#include "common/matrix_utils.h"
#include "compiler/translator/Diagnostics.h"
#include "compiler/translator/IntermNode.h"
#include "compiler/translator/SymbolTable.h"
#include "compiler/translator/util.h"

namespace sh
{

namespace
{

const float kPi                         = 3.14159265358979323846f;
const float kDegreesToRadiansMultiplier = kPi / 180.0f;
const float kRadiansToDegreesMultiplier = 180.0f / kPi;

TPrecision GetHigherPrecision(TPrecision left, TPrecision right)
{
    return left > right ? left : right;
}

TConstantUnion *Vectorize(const TConstantUnion &constant, size_t size)
{
    TConstantUnion *constUnion = new TConstantUnion[size];
    for (unsigned int i = 0; i < size; ++i)
        constUnion[i]   = constant;

    return constUnion;
}

void UndefinedConstantFoldingError(const TSourceLoc &loc,
                                   TOperator op,
                                   TBasicType basicType,
                                   TDiagnostics *diagnostics,
                                   TConstantUnion *result)
{
    diagnostics->warning(loc, "operation result is undefined for the values passed in",
                         GetOperatorString(op));

    switch (basicType)
    {
        case EbtFloat:
            result->setFConst(0.0f);
            break;
        case EbtInt:
            result->setIConst(0);
            break;
        case EbtUInt:
            result->setUConst(0u);
            break;
        case EbtBool:
            result->setBConst(false);
            break;
        default:
            break;
    }
}

float VectorLength(const TConstantUnion *paramArray, size_t paramArraySize)
{
    float result = 0.0f;
    for (size_t i = 0; i < paramArraySize; i++)
    {
        float f = paramArray[i].getFConst();
        result += f * f;
    }
    return sqrtf(result);
}

float VectorDotProduct(const TConstantUnion *paramArray1,
                       const TConstantUnion *paramArray2,
                       size_t paramArraySize)
{
    float result = 0.0f;
    for (size_t i = 0; i < paramArraySize; i++)
        result += paramArray1[i].getFConst() * paramArray2[i].getFConst();
    return result;
}

TIntermTyped *CreateFoldedNode(const TConstantUnion *constArray,
                               const TIntermTyped *originalNode,
                               TQualifier qualifier)
{
    if (constArray == nullptr)
    {
        return nullptr;
    }
    TIntermTyped *folded = new TIntermConstantUnion(constArray, originalNode->getType());
    folded->getTypePointer()->setQualifier(qualifier);
    folded->setLine(originalNode->getLine());
    return folded;
}

angle::Matrix<float> GetMatrix(const TConstantUnion *paramArray,
                               const unsigned int &rows,
                               const unsigned int &cols)
{
    std::vector<float> elements;
    for (size_t i = 0; i < rows * cols; i++)
        elements.push_back(paramArray[i].getFConst());
    // Transpose is used since the Matrix constructor expects arguments in row-major order,
    // whereas the paramArray is in column-major order. Rows/cols parameters are also flipped below
    // so that the created matrix will have the expected dimensions after the transpose.
    return angle::Matrix<float>(elements, cols, rows).transpose();
}

angle::Matrix<float> GetMatrix(const TConstantUnion *paramArray, const unsigned int &size)
{
    std::vector<float> elements;
    for (size_t i = 0; i < size * size; i++)
        elements.push_back(paramArray[i].getFConst());
    // Transpose is used since the Matrix constructor expects arguments in row-major order,
    // whereas the paramArray is in column-major order.
    return angle::Matrix<float>(elements, size).transpose();
}

void SetUnionArrayFromMatrix(const angle::Matrix<float> &m, TConstantUnion *resultArray)
{
    // Transpose is used since the input Matrix is in row-major order,
    // whereas the actual result should be in column-major order.
    angle::Matrix<float> result       = m.transpose();
    std::vector<float> resultElements = result.elements();
    for (size_t i = 0; i < resultElements.size(); i++)
        resultArray[i].setFConst(resultElements[i]);
}

}  // namespace anonymous

////////////////////////////////////////////////////////////////
//
// Member functions of the nodes used for building the tree.
//
////////////////////////////////////////////////////////////////

void TIntermTyped::setTypePreservePrecision(const TType &t)
{
    TPrecision precision = getPrecision();
    mType                = t;
    ASSERT(mType.getBasicType() != EbtBool || precision == EbpUndefined);
    mType.setPrecision(precision);
}

#define REPLACE_IF_IS(node, type, original, replacement) \
    if (node == original)                                \
    {                                                    \
        node = static_cast<type *>(replacement);         \
        return true;                                     \
    }

bool TIntermLoop::replaceChildNode(TIntermNode *original, TIntermNode *replacement)
{
    ASSERT(original != nullptr);  // This risks replacing multiple children.
    REPLACE_IF_IS(mInit, TIntermNode, original, replacement);
    REPLACE_IF_IS(mCond, TIntermTyped, original, replacement);
    REPLACE_IF_IS(mExpr, TIntermTyped, original, replacement);
    REPLACE_IF_IS(mBody, TIntermBlock, original, replacement);
    return false;
}

bool TIntermBranch::replaceChildNode(TIntermNode *original, TIntermNode *replacement)
{
    REPLACE_IF_IS(mExpression, TIntermTyped, original, replacement);
    return false;
}

bool TIntermSwizzle::replaceChildNode(TIntermNode *original, TIntermNode *replacement)
{
    ASSERT(original->getAsTyped()->getType() == replacement->getAsTyped()->getType());
    REPLACE_IF_IS(mOperand, TIntermTyped, original, replacement);
    return false;
}

bool TIntermBinary::replaceChildNode(TIntermNode *original, TIntermNode *replacement)
{
    REPLACE_IF_IS(mLeft, TIntermTyped, original, replacement);
    REPLACE_IF_IS(mRight, TIntermTyped, original, replacement);
    return false;
}

bool TIntermUnary::replaceChildNode(TIntermNode *original, TIntermNode *replacement)
{
    ASSERT(original->getAsTyped()->getType() == replacement->getAsTyped()->getType());
    REPLACE_IF_IS(mOperand, TIntermTyped, original, replacement);
    return false;
}

bool TIntermInvariantDeclaration::replaceChildNode(TIntermNode *original, TIntermNode *replacement)
{
    REPLACE_IF_IS(mSymbol, TIntermSymbol, original, replacement);
    return false;
}

bool TIntermFunctionDefinition::replaceChildNode(TIntermNode *original, TIntermNode *replacement)
{
    REPLACE_IF_IS(mPrototype, TIntermFunctionPrototype, original, replacement);
    REPLACE_IF_IS(mBody, TIntermBlock, original, replacement);
    return false;
}

bool TIntermAggregate::replaceChildNode(TIntermNode *original, TIntermNode *replacement)
{
    return replaceChildNodeInternal(original, replacement);
}

bool TIntermBlock::replaceChildNode(TIntermNode *original, TIntermNode *replacement)
{
    return replaceChildNodeInternal(original, replacement);
}

bool TIntermFunctionPrototype::replaceChildNode(TIntermNode *original, TIntermNode *replacement)
{
    return replaceChildNodeInternal(original, replacement);
}

bool TIntermDeclaration::replaceChildNode(TIntermNode *original, TIntermNode *replacement)
{
    return replaceChildNodeInternal(original, replacement);
}

bool TIntermAggregateBase::replaceChildNodeInternal(TIntermNode *original, TIntermNode *replacement)
{
    for (size_t ii = 0; ii < getSequence()->size(); ++ii)
    {
        REPLACE_IF_IS((*getSequence())[ii], TIntermNode, original, replacement);
    }
    return false;
}

bool TIntermAggregateBase::replaceChildNodeWithMultiple(TIntermNode *original,
                                                        const TIntermSequence &replacements)
{
    for (auto it = getSequence()->begin(); it < getSequence()->end(); ++it)
    {
        if (*it == original)
        {
            it = getSequence()->erase(it);
            getSequence()->insert(it, replacements.begin(), replacements.end());
            return true;
        }
    }
    return false;
}

bool TIntermAggregateBase::insertChildNodes(TIntermSequence::size_type position,
                                            const TIntermSequence &insertions)
{
    if (position > getSequence()->size())
    {
        return false;
    }
    auto it = getSequence()->begin() + position;
    getSequence()->insert(it, insertions.begin(), insertions.end());
    return true;
}

TIntermAggregate *TIntermAggregate::CreateFunctionCall(const TFunction &func,
                                                       TIntermSequence *arguments)
{
    TIntermAggregate *callNode =
        new TIntermAggregate(func.getReturnType(), EOpCallFunctionInAST, arguments);
    callNode->getFunctionSymbolInfo()->setFromFunction(func);
    return callNode;
}

TIntermAggregate *TIntermAggregate::CreateFunctionCall(const TType &type,
                                                       const TSymbolUniqueId &id,
                                                       const TName &name,
                                                       TIntermSequence *arguments)
{
    TIntermAggregate *callNode = new TIntermAggregate(type, EOpCallFunctionInAST, arguments);
    callNode->getFunctionSymbolInfo()->setId(id);
    callNode->getFunctionSymbolInfo()->setNameObj(name);
    return callNode;
}

TIntermAggregate *TIntermAggregate::CreateBuiltInFunctionCall(const TFunction &func,
                                                              TIntermSequence *arguments)
{
    TIntermAggregate *callNode =
        new TIntermAggregate(func.getReturnType(), EOpCallBuiltInFunction, arguments);
    callNode->getFunctionSymbolInfo()->setFromFunction(func);
    // Note that name needs to be set before texture function type is determined.
    callNode->setBuiltInFunctionPrecision();
    return callNode;
}

TIntermAggregate *TIntermAggregate::CreateConstructor(const TType &type,
                                                      TIntermSequence *arguments)
{
    return new TIntermAggregate(type, EOpConstruct, arguments);
}

TIntermAggregate *TIntermAggregate::Create(const TType &type,
                                           TOperator op,
                                           TIntermSequence *arguments)
{
    TIntermAggregate *node = new TIntermAggregate(type, op, arguments);
    ASSERT(op != EOpCallFunctionInAST);    // Should use CreateFunctionCall
    ASSERT(op != EOpCallBuiltInFunction);  // Should use CreateBuiltInFunctionCall
    ASSERT(!node->isConstructor());        // Should use CreateConstructor
    return node;
}

TIntermAggregate::TIntermAggregate(const TType &type, TOperator op, TIntermSequence *arguments)
    : TIntermOperator(op), mUseEmulatedFunction(false), mGotPrecisionFromChildren(false)
{
    if (arguments != nullptr)
    {
        mArguments.swap(*arguments);
    }
    setTypePrecisionAndQualifier(type);
}

void TIntermAggregate::setTypePrecisionAndQualifier(const TType &type)
{
    setType(type);
    mType.setQualifier(EvqTemporary);
    if (!isFunctionCall())
    {
        if (isConstructor())
        {
            // Structs should not be precision qualified, the individual members may be.
            // Built-in types on the other hand should be precision qualified.
            if (getBasicType() != EbtStruct)
            {
                setPrecisionFromChildren();
            }
        }
        else
        {
            setPrecisionForBuiltInOp();
        }
        if (areChildrenConstQualified())
        {
            mType.setQualifier(EvqConst);
        }
    }
}

bool TIntermAggregate::areChildrenConstQualified()
{
    for (TIntermNode *&arg : mArguments)
    {
        TIntermTyped *typedArg = arg->getAsTyped();
        if (typedArg && typedArg->getQualifier() != EvqConst)
        {
            return false;
        }
    }
    return true;
}

void TIntermAggregate::setPrecisionFromChildren()
{
    mGotPrecisionFromChildren = true;
    if (getBasicType() == EbtBool)
    {
        mType.setPrecision(EbpUndefined);
        return;
    }

    TPrecision precision                = EbpUndefined;
    TIntermSequence::iterator childIter = mArguments.begin();
    while (childIter != mArguments.end())
    {
        TIntermTyped *typed = (*childIter)->getAsTyped();
        if (typed)
            precision = GetHigherPrecision(typed->getPrecision(), precision);
        ++childIter;
    }
    mType.setPrecision(precision);
}

void TIntermAggregate::setPrecisionForBuiltInOp()
{
    ASSERT(!isConstructor());
    ASSERT(!isFunctionCall());
    if (!setPrecisionForSpecialBuiltInOp())
    {
        setPrecisionFromChildren();
    }
}

bool TIntermAggregate::setPrecisionForSpecialBuiltInOp()
{
    switch (mOp)
    {
        case EOpBitfieldExtract:
            mType.setPrecision(mArguments[0]->getAsTyped()->getPrecision());
            mGotPrecisionFromChildren = true;
            return true;
        case EOpBitfieldInsert:
            mType.setPrecision(GetHigherPrecision(mArguments[0]->getAsTyped()->getPrecision(),
                                                  mArguments[1]->getAsTyped()->getPrecision()));
            mGotPrecisionFromChildren = true;
            return true;
        case EOpUaddCarry:
        case EOpUsubBorrow:
            mType.setPrecision(EbpHigh);
            return true;
        default:
            return false;
    }
}

void TIntermAggregate::setBuiltInFunctionPrecision()
{
    // All built-ins returning bool should be handled as ops, not functions.
    ASSERT(getBasicType() != EbtBool);
    ASSERT(mOp == EOpCallBuiltInFunction);

    TPrecision precision = EbpUndefined;
    for (TIntermNode *arg : mArguments)
    {
        TIntermTyped *typed = arg->getAsTyped();
        // ESSL spec section 8: texture functions get their precision from the sampler.
        if (typed && IsSampler(typed->getBasicType()))
        {
            precision = typed->getPrecision();
            break;
        }
    }
    // ESSL 3.0 spec section 8: textureSize always gets highp precision.
    // All other functions that take a sampler are assumed to be texture functions.
    if (mFunctionInfo.getName().find("textureSize") == 0)
        mType.setPrecision(EbpHigh);
    else
        mType.setPrecision(precision);
}

TString TIntermAggregate::getSymbolTableMangledName() const
{
    ASSERT(!isConstructor());
    switch (mOp)
    {
        case EOpCallInternalRawFunction:
        case EOpCallBuiltInFunction:
        case EOpCallFunctionInAST:
            return TFunction::GetMangledNameFromCall(mFunctionInfo.getName(), mArguments);
        default:
            TString opString = GetOperatorString(mOp);
            return TFunction::GetMangledNameFromCall(opString, mArguments);
    }
}

bool TIntermAggregate::hasSideEffects() const
{
    if (isFunctionCall() && mFunctionInfo.isKnownToNotHaveSideEffects())
    {
        for (TIntermNode *arg : mArguments)
        {
            if (arg->getAsTyped()->hasSideEffects())
            {
                return true;
            }
        }
        return false;
    }
    // Conservatively assume most aggregate operators have side-effects
    return true;
}

void TIntermBlock::appendStatement(TIntermNode *statement)
{
    // Declaration nodes with no children can appear if it was an empty declaration or if all the
    // declarators just added constants to the symbol table instead of generating code. We still
    // need to add the declaration to the AST in that case because it might be relevant to the
    // validity of switch/case.
    if (statement != nullptr)
    {
        mStatements.push_back(statement);
    }
}

void TIntermFunctionPrototype::appendParameter(TIntermSymbol *parameter)
{
    ASSERT(parameter != nullptr);
    mParameters.push_back(parameter);
}

void TIntermDeclaration::appendDeclarator(TIntermTyped *declarator)
{
    ASSERT(declarator != nullptr);
    ASSERT(declarator->getAsSymbolNode() != nullptr ||
           (declarator->getAsBinaryNode() != nullptr &&
            declarator->getAsBinaryNode()->getOp() == EOpInitialize));
    ASSERT(mDeclarators.empty() ||
           declarator->getType().sameNonArrayType(mDeclarators.back()->getAsTyped()->getType()));
    mDeclarators.push_back(declarator);
}

bool TIntermTernary::replaceChildNode(TIntermNode *original, TIntermNode *replacement)
{
    REPLACE_IF_IS(mCondition, TIntermTyped, original, replacement);
    REPLACE_IF_IS(mTrueExpression, TIntermTyped, original, replacement);
    REPLACE_IF_IS(mFalseExpression, TIntermTyped, original, replacement);
    return false;
}

bool TIntermIfElse::replaceChildNode(TIntermNode *original, TIntermNode *replacement)
{
    REPLACE_IF_IS(mCondition, TIntermTyped, original, replacement);
    REPLACE_IF_IS(mTrueBlock, TIntermBlock, original, replacement);
    REPLACE_IF_IS(mFalseBlock, TIntermBlock, original, replacement);
    return false;
}

bool TIntermSwitch::replaceChildNode(TIntermNode *original, TIntermNode *replacement)
{
    REPLACE_IF_IS(mInit, TIntermTyped, original, replacement);
    REPLACE_IF_IS(mStatementList, TIntermBlock, original, replacement);
    ASSERT(mStatementList);
    return false;
}

bool TIntermCase::replaceChildNode(TIntermNode *original, TIntermNode *replacement)
{
    REPLACE_IF_IS(mCondition, TIntermTyped, original, replacement);
    return false;
}

TIntermTyped::TIntermTyped(const TIntermTyped &node) : TIntermNode(), mType(node.mType)
{
    // Copy constructor is disallowed for TIntermNode in order to disallow it for subclasses that
    // don't explicitly allow it, so normal TIntermNode constructor is used to construct the copy.
    // We need to manually copy any fields of TIntermNode besides handling fields in TIntermTyped.
    mLine = node.mLine;
}

bool TIntermTyped::isConstructorWithOnlyConstantUnionParameters()
{
    TIntermAggregate *constructor = getAsAggregate();
    if (!constructor || !constructor->isConstructor())
    {
        return false;
    }
    for (TIntermNode *&node : *constructor->getSequence())
    {
        if (!node->getAsConstantUnion())
            return false;
    }
    return true;
}

TIntermConstantUnion::TIntermConstantUnion(const TIntermConstantUnion &node) : TIntermTyped(node)
{
    mUnionArrayPointer = node.mUnionArrayPointer;
}

void TFunctionSymbolInfo::setFromFunction(const TFunction &function)
{
    setName(function.getName());
    setId(TSymbolUniqueId(function));
}

TFunctionSymbolInfo::TFunctionSymbolInfo(const TSymbolUniqueId &id)
    : mId(new TSymbolUniqueId(id)), mKnownToNotHaveSideEffects(false)
{
}

TFunctionSymbolInfo::TFunctionSymbolInfo(const TFunctionSymbolInfo &info)
    : mName(info.mName), mId(nullptr), mKnownToNotHaveSideEffects(info.mKnownToNotHaveSideEffects)
{
    if (info.mId)
    {
        mId = new TSymbolUniqueId(*info.mId);
    }
}

TFunctionSymbolInfo &TFunctionSymbolInfo::operator=(const TFunctionSymbolInfo &info)
{
    mName = info.mName;
    if (info.mId)
    {
        mId = new TSymbolUniqueId(*info.mId);
    }
    else
    {
        mId = nullptr;
    }
    return *this;
}

void TFunctionSymbolInfo::setId(const TSymbolUniqueId &id)
{
    mId = new TSymbolUniqueId(id);
}

const TSymbolUniqueId &TFunctionSymbolInfo::getId() const
{
    ASSERT(mId);
    return *mId;
}

TIntermAggregate::TIntermAggregate(const TIntermAggregate &node)
    : TIntermOperator(node),
      mUseEmulatedFunction(node.mUseEmulatedFunction),
      mGotPrecisionFromChildren(node.mGotPrecisionFromChildren),
      mFunctionInfo(node.mFunctionInfo)
{
    for (TIntermNode *arg : node.mArguments)
    {
        TIntermTyped *typedArg = arg->getAsTyped();
        ASSERT(typedArg != nullptr);
        TIntermTyped *argCopy = typedArg->deepCopy();
        mArguments.push_back(argCopy);
    }
}

TIntermAggregate *TIntermAggregate::shallowCopy() const
{
    TIntermSequence *copySeq = new TIntermSequence();
    copySeq->insert(copySeq->begin(), getSequence()->begin(), getSequence()->end());
    TIntermAggregate *copyNode         = new TIntermAggregate(mType, mOp, copySeq);
    *copyNode->getFunctionSymbolInfo() = mFunctionInfo;
    copyNode->setLine(mLine);
    return copyNode;
}

TIntermSwizzle::TIntermSwizzle(const TIntermSwizzle &node) : TIntermTyped(node)
{
    TIntermTyped *operandCopy = node.mOperand->deepCopy();
    ASSERT(operandCopy != nullptr);
    mOperand = operandCopy;
    mSwizzleOffsets = node.mSwizzleOffsets;
}

TIntermBinary::TIntermBinary(const TIntermBinary &node)
    : TIntermOperator(node), mAddIndexClamp(node.mAddIndexClamp)
{
    TIntermTyped *leftCopy  = node.mLeft->deepCopy();
    TIntermTyped *rightCopy = node.mRight->deepCopy();
    ASSERT(leftCopy != nullptr && rightCopy != nullptr);
    mLeft  = leftCopy;
    mRight = rightCopy;
}

TIntermUnary::TIntermUnary(const TIntermUnary &node)
    : TIntermOperator(node), mUseEmulatedFunction(node.mUseEmulatedFunction)
{
    TIntermTyped *operandCopy = node.mOperand->deepCopy();
    ASSERT(operandCopy != nullptr);
    mOperand = operandCopy;
}

TIntermTernary::TIntermTernary(const TIntermTernary &node) : TIntermTyped(node)
{
    TIntermTyped *conditionCopy = node.mCondition->deepCopy();
    TIntermTyped *trueCopy      = node.mTrueExpression->deepCopy();
    TIntermTyped *falseCopy     = node.mFalseExpression->deepCopy();
    ASSERT(conditionCopy != nullptr && trueCopy != nullptr && falseCopy != nullptr);
    mCondition       = conditionCopy;
    mTrueExpression  = trueCopy;
    mFalseExpression = falseCopy;
}

bool TIntermOperator::isAssignment() const
{
    return IsAssignment(mOp);
}

bool TIntermOperator::isMultiplication() const
{
    switch (mOp)
    {
        case EOpMul:
        case EOpMatrixTimesMatrix:
        case EOpMatrixTimesVector:
        case EOpMatrixTimesScalar:
        case EOpVectorTimesMatrix:
        case EOpVectorTimesScalar:
            return true;
        default:
            return false;
    }
}

bool TIntermOperator::isConstructor() const
{
    return (mOp == EOpConstruct);
}

bool TIntermOperator::isFunctionCall() const
{
    switch (mOp)
    {
        case EOpCallFunctionInAST:
        case EOpCallBuiltInFunction:
        case EOpCallInternalRawFunction:
            return true;
        default:
            return false;
    }
}

TOperator TIntermBinary::GetMulOpBasedOnOperands(const TType &left, const TType &right)
{
    if (left.isMatrix())
    {
        if (right.isMatrix())
        {
            return EOpMatrixTimesMatrix;
        }
        else
        {
            if (right.isVector())
            {
                return EOpMatrixTimesVector;
            }
            else
            {
                return EOpMatrixTimesScalar;
            }
        }
    }
    else
    {
        if (right.isMatrix())
        {
            if (left.isVector())
            {
                return EOpVectorTimesMatrix;
            }
            else
            {
                return EOpMatrixTimesScalar;
            }
        }
        else
        {
            // Neither operand is a matrix.
            if (left.isVector() == right.isVector())
            {
                // Leave as component product.
                return EOpMul;
            }
            else
            {
                return EOpVectorTimesScalar;
            }
        }
    }
}

TOperator TIntermBinary::GetMulAssignOpBasedOnOperands(const TType &left, const TType &right)
{
    if (left.isMatrix())
    {
        if (right.isMatrix())
        {
            return EOpMatrixTimesMatrixAssign;
        }
        else
        {
            // right should be scalar, but this may not be validated yet.
            return EOpMatrixTimesScalarAssign;
        }
    }
    else
    {
        if (right.isMatrix())
        {
            // Left should be a vector, but this may not be validated yet.
            return EOpVectorTimesMatrixAssign;
        }
        else
        {
            // Neither operand is a matrix.
            if (left.isVector() == right.isVector())
            {
                // Leave as component product.
                return EOpMulAssign;
            }
            else
            {
                // left should be vector and right should be scalar, but this may not be validated
                // yet.
                return EOpVectorTimesScalarAssign;
            }
        }
    }
}

//
// Make sure the type of a unary operator is appropriate for its
// combination of operation and operand type.
//
void TIntermUnary::promote()
{
    if (mOp == EOpArrayLength)
    {
        // Special case: the qualifier of .length() doesn't depend on the operand qualifier.
        setType(TType(EbtInt, EbpUndefined, EvqConst));
        return;
    }

    TQualifier resultQualifier = EvqTemporary;
    if (mOperand->getQualifier() == EvqConst)
        resultQualifier = EvqConst;

    unsigned char operandPrimarySize =
        static_cast<unsigned char>(mOperand->getType().getNominalSize());
    switch (mOp)
    {
        case EOpFloatBitsToInt:
            setType(TType(EbtInt, EbpHigh, resultQualifier, operandPrimarySize));
            break;
        case EOpFloatBitsToUint:
            setType(TType(EbtUInt, EbpHigh, resultQualifier, operandPrimarySize));
            break;
        case EOpIntBitsToFloat:
        case EOpUintBitsToFloat:
            setType(TType(EbtFloat, EbpHigh, resultQualifier, operandPrimarySize));
            break;
        case EOpPackSnorm2x16:
        case EOpPackUnorm2x16:
        case EOpPackHalf2x16:
        case EOpPackUnorm4x8:
        case EOpPackSnorm4x8:
            setType(TType(EbtUInt, EbpHigh, resultQualifier));
            break;
        case EOpUnpackSnorm2x16:
        case EOpUnpackUnorm2x16:
            setType(TType(EbtFloat, EbpHigh, resultQualifier, 2));
            break;
        case EOpUnpackHalf2x16:
            setType(TType(EbtFloat, EbpMedium, resultQualifier, 2));
            break;
        case EOpUnpackUnorm4x8:
        case EOpUnpackSnorm4x8:
            setType(TType(EbtFloat, EbpMedium, resultQualifier, 4));
            break;
        case EOpAny:
        case EOpAll:
            setType(TType(EbtBool, EbpUndefined, resultQualifier));
            break;
        case EOpLength:
        case EOpDeterminant:
            setType(TType(EbtFloat, mOperand->getType().getPrecision(), resultQualifier));
            break;
        case EOpTranspose:
            setType(TType(EbtFloat, mOperand->getType().getPrecision(), resultQualifier,
                          static_cast<unsigned char>(mOperand->getType().getRows()),
                          static_cast<unsigned char>(mOperand->getType().getCols())));
            break;
        case EOpIsInf:
        case EOpIsNan:
            setType(TType(EbtBool, EbpUndefined, resultQualifier, operandPrimarySize));
            break;
        case EOpBitfieldReverse:
            setType(TType(mOperand->getBasicType(), EbpHigh, resultQualifier, operandPrimarySize));
            break;
        case EOpBitCount:
            setType(TType(EbtInt, EbpLow, resultQualifier, operandPrimarySize));
            break;
        case EOpFindLSB:
            setType(TType(EbtInt, EbpLow, resultQualifier, operandPrimarySize));
            break;
        case EOpFindMSB:
            setType(TType(EbtInt, EbpLow, resultQualifier, operandPrimarySize));
            break;
        default:
            setType(mOperand->getType());
            mType.setQualifier(resultQualifier);
            break;
    }
}

TIntermSwizzle::TIntermSwizzle(TIntermTyped *operand, const TVector<int> &swizzleOffsets)
    : TIntermTyped(TType(EbtFloat, EbpUndefined)),
      mOperand(operand),
      mSwizzleOffsets(swizzleOffsets)
{
    ASSERT(mSwizzleOffsets.size() <= 4);
    promote();
}

TIntermUnary::TIntermUnary(TOperator op, TIntermTyped *operand)
    : TIntermOperator(op), mOperand(operand), mUseEmulatedFunction(false)
{
    promote();
}

TIntermBinary::TIntermBinary(TOperator op, TIntermTyped *left, TIntermTyped *right)
    : TIntermOperator(op), mLeft(left), mRight(right), mAddIndexClamp(false)
{
    promote();
}

TIntermInvariantDeclaration::TIntermInvariantDeclaration(TIntermSymbol *symbol, const TSourceLoc &line)
    : TIntermNode(), mSymbol(symbol)
{
    ASSERT(symbol);
    setLine(line);
}

TIntermTernary::TIntermTernary(TIntermTyped *cond,
                               TIntermTyped *trueExpression,
                               TIntermTyped *falseExpression)
    : TIntermTyped(trueExpression->getType()),
      mCondition(cond),
      mTrueExpression(trueExpression),
      mFalseExpression(falseExpression)
{
    getTypePointer()->setQualifier(
        TIntermTernary::DetermineQualifier(cond, trueExpression, falseExpression));
}

TIntermLoop::TIntermLoop(TLoopType type,
                         TIntermNode *init,
                         TIntermTyped *cond,
                         TIntermTyped *expr,
                         TIntermBlock *body)
    : mType(type), mInit(init), mCond(cond), mExpr(expr), mBody(body)
{
    // Declaration nodes with no children can appear if all the declarators just added constants to
    // the symbol table instead of generating code. They're no-ops so don't add them to the tree.
    if (mInit && mInit->getAsDeclarationNode() &&
        mInit->getAsDeclarationNode()->getSequence()->empty())
    {
        mInit = nullptr;
    }
}

TIntermIfElse::TIntermIfElse(TIntermTyped *cond, TIntermBlock *trueB, TIntermBlock *falseB)
    : TIntermNode(), mCondition(cond), mTrueBlock(trueB), mFalseBlock(falseB)
{
    // Prune empty false blocks so that there won't be unnecessary operations done on it.
    if (mFalseBlock && mFalseBlock->getSequence()->empty())
    {
        mFalseBlock = nullptr;
    }
}

TIntermSwitch::TIntermSwitch(TIntermTyped *init, TIntermBlock *statementList)
    : TIntermNode(), mInit(init), mStatementList(statementList)
{
    ASSERT(mStatementList);
}

void TIntermSwitch::setStatementList(TIntermBlock *statementList)
{
    ASSERT(statementList);
    mStatementList = statementList;
}

// static
TQualifier TIntermTernary::DetermineQualifier(TIntermTyped *cond,
                                              TIntermTyped *trueExpression,
                                              TIntermTyped *falseExpression)
{
    if (cond->getQualifier() == EvqConst && trueExpression->getQualifier() == EvqConst &&
        falseExpression->getQualifier() == EvqConst)
    {
        return EvqConst;
    }
    return EvqTemporary;
}

TIntermTyped *TIntermTernary::fold()
{
    if (mCondition->getAsConstantUnion())
    {
        if (mCondition->getAsConstantUnion()->getBConst(0))
        {
            mTrueExpression->getTypePointer()->setQualifier(mType.getQualifier());
            return mTrueExpression;
        }
        else
        {
            mFalseExpression->getTypePointer()->setQualifier(mType.getQualifier());
            return mFalseExpression;
        }
    }
    return this;
}

void TIntermSwizzle::promote()
{
    TQualifier resultQualifier = EvqTemporary;
    if (mOperand->getQualifier() == EvqConst)
        resultQualifier = EvqConst;

    auto numFields = mSwizzleOffsets.size();
    setType(TType(mOperand->getBasicType(), mOperand->getPrecision(), resultQualifier,
                  static_cast<unsigned char>(numFields)));
}

bool TIntermSwizzle::hasDuplicateOffsets() const
{
    int offsetCount[4] = {0u, 0u, 0u, 0u};
    for (const auto offset : mSwizzleOffsets)
    {
        offsetCount[offset]++;
        if (offsetCount[offset] > 1)
        {
            return true;
        }
    }
    return false;
}

bool TIntermSwizzle::offsetsMatch(int offset) const
{
    return mSwizzleOffsets.size() == 1 && mSwizzleOffsets[0] == offset;
}

void TIntermSwizzle::writeOffsetsAsXYZW(TInfoSinkBase *out) const
{
    for (const int offset : mSwizzleOffsets)
    {
        switch (offset)
        {
            case 0:
                *out << "x";
                break;
            case 1:
                *out << "y";
                break;
            case 2:
                *out << "z";
                break;
            case 3:
                *out << "w";
                break;
            default:
                UNREACHABLE();
        }
    }
}

TQualifier TIntermBinary::GetCommaQualifier(int shaderVersion,
                                            const TIntermTyped *left,
                                            const TIntermTyped *right)
{
    // ESSL3.00 section 12.43: The result of a sequence operator is not a constant-expression.
    if (shaderVersion >= 300 || left->getQualifier() != EvqConst ||
        right->getQualifier() != EvqConst)
    {
        return EvqTemporary;
    }
    return EvqConst;
}

// Establishes the type of the result of the binary operation.
void TIntermBinary::promote()
{
    ASSERT(!isMultiplication() ||
           mOp == GetMulOpBasedOnOperands(mLeft->getType(), mRight->getType()));

    // Comma is handled as a special case. Note that the comma node qualifier depends on the shader
    // version and so is not being set here.
    if (mOp == EOpComma)
    {
        setType(mRight->getType());
        return;
    }

    // Base assumption:  just make the type the same as the left
    // operand.  Then only deviations from this need be coded.
    setType(mLeft->getType());

    TQualifier resultQualifier = EvqConst;
    // Binary operations results in temporary variables unless both
    // operands are const.
    if (mLeft->getQualifier() != EvqConst || mRight->getQualifier() != EvqConst)
    {
        resultQualifier = EvqTemporary;
        getTypePointer()->setQualifier(EvqTemporary);
    }

    // Handle indexing ops.
    switch (mOp)
    {
        case EOpIndexDirect:
        case EOpIndexIndirect:
            if (mLeft->isArray())
            {
                mType.toArrayElementType();
            }
            else if (mLeft->isMatrix())
            {
                setType(TType(mLeft->getBasicType(), mLeft->getPrecision(), resultQualifier,
                              static_cast<unsigned char>(mLeft->getRows())));
            }
            else if (mLeft->isVector())
            {
                setType(TType(mLeft->getBasicType(), mLeft->getPrecision(), resultQualifier));
            }
            else
            {
                UNREACHABLE();
            }
            return;
        case EOpIndexDirectStruct:
        {
            const TFieldList &fields = mLeft->getType().getStruct()->fields();
            const int i              = mRight->getAsConstantUnion()->getIConst(0);
            setType(*fields[i]->type());
            getTypePointer()->setQualifier(resultQualifier);
            return;
        }
        case EOpIndexDirectInterfaceBlock:
        {
            const TFieldList &fields = mLeft->getType().getInterfaceBlock()->fields();
            const int i              = mRight->getAsConstantUnion()->getIConst(0);
            setType(*fields[i]->type());
            getTypePointer()->setQualifier(resultQualifier);
            return;
        }
        default:
            break;
    }

    ASSERT(mLeft->isArray() == mRight->isArray());

    // The result gets promoted to the highest precision.
    TPrecision higherPrecision = GetHigherPrecision(mLeft->getPrecision(), mRight->getPrecision());
    getTypePointer()->setPrecision(higherPrecision);

    const int nominalSize = std::max(mLeft->getNominalSize(), mRight->getNominalSize());

    //
    // All scalars or structs. Code after this test assumes this case is removed!
    //
    if (nominalSize == 1)
    {
        switch (mOp)
        {
            //
            // Promote to conditional
            //
            case EOpEqual:
            case EOpNotEqual:
            case EOpLessThan:
            case EOpGreaterThan:
            case EOpLessThanEqual:
            case EOpGreaterThanEqual:
                setType(TType(EbtBool, EbpUndefined, resultQualifier));
                break;

            //
            // And and Or operate on conditionals
            //
            case EOpLogicalAnd:
            case EOpLogicalXor:
            case EOpLogicalOr:
                ASSERT(mLeft->getBasicType() == EbtBool && mRight->getBasicType() == EbtBool);
                setType(TType(EbtBool, EbpUndefined, resultQualifier));
                break;

            default:
                break;
        }
        return;
    }

    // If we reach here, at least one of the operands is vector or matrix.
    // The other operand could be a scalar, vector, or matrix.
    TBasicType basicType = mLeft->getBasicType();

    switch (mOp)
    {
        case EOpMul:
            break;
        case EOpMatrixTimesScalar:
            if (mRight->isMatrix())
            {
                setType(TType(basicType, higherPrecision, resultQualifier,
                              static_cast<unsigned char>(mRight->getCols()),
                              static_cast<unsigned char>(mRight->getRows())));
            }
            break;
        case EOpMatrixTimesVector:
            setType(TType(basicType, higherPrecision, resultQualifier,
                          static_cast<unsigned char>(mLeft->getRows()), 1));
            break;
        case EOpMatrixTimesMatrix:
            setType(TType(basicType, higherPrecision, resultQualifier,
                          static_cast<unsigned char>(mRight->getCols()),
                          static_cast<unsigned char>(mLeft->getRows())));
            break;
        case EOpVectorTimesScalar:
            setType(TType(basicType, higherPrecision, resultQualifier,
                          static_cast<unsigned char>(nominalSize), 1));
            break;
        case EOpVectorTimesMatrix:
            setType(TType(basicType, higherPrecision, resultQualifier,
                          static_cast<unsigned char>(mRight->getCols()), 1));
            break;
        case EOpMulAssign:
        case EOpVectorTimesScalarAssign:
        case EOpVectorTimesMatrixAssign:
        case EOpMatrixTimesScalarAssign:
        case EOpMatrixTimesMatrixAssign:
            ASSERT(mOp == GetMulAssignOpBasedOnOperands(mLeft->getType(), mRight->getType()));
            break;
        case EOpAssign:
        case EOpInitialize:
            ASSERT((mLeft->getNominalSize() == mRight->getNominalSize()) &&
                   (mLeft->getSecondarySize() == mRight->getSecondarySize()));
            break;
        case EOpAdd:
        case EOpSub:
        case EOpDiv:
        case EOpIMod:
        case EOpBitShiftLeft:
        case EOpBitShiftRight:
        case EOpBitwiseAnd:
        case EOpBitwiseXor:
        case EOpBitwiseOr:
        case EOpAddAssign:
        case EOpSubAssign:
        case EOpDivAssign:
        case EOpIModAssign:
        case EOpBitShiftLeftAssign:
        case EOpBitShiftRightAssign:
        case EOpBitwiseAndAssign:
        case EOpBitwiseXorAssign:
        case EOpBitwiseOrAssign:
        {
            const int secondarySize =
                std::max(mLeft->getSecondarySize(), mRight->getSecondarySize());
            setType(TType(basicType, higherPrecision, resultQualifier,
                          static_cast<unsigned char>(nominalSize),
                          static_cast<unsigned char>(secondarySize)));
            ASSERT(!mLeft->isArray() && !mRight->isArray());
            break;
        }
        case EOpEqual:
        case EOpNotEqual:
        case EOpLessThan:
        case EOpGreaterThan:
        case EOpLessThanEqual:
        case EOpGreaterThanEqual:
            ASSERT((mLeft->getNominalSize() == mRight->getNominalSize()) &&
                   (mLeft->getSecondarySize() == mRight->getSecondarySize()));
            setType(TType(EbtBool, EbpUndefined, resultQualifier));
            break;

        case EOpIndexDirect:
        case EOpIndexIndirect:
        case EOpIndexDirectInterfaceBlock:
        case EOpIndexDirectStruct:
            // These ops should be already fully handled.
            UNREACHABLE();
            break;
        default:
            UNREACHABLE();
            break;
    }
}

const TConstantUnion *TIntermConstantUnion::foldIndexing(int index)
{
    if (isArray())
    {
        ASSERT(index < static_cast<int>(getType().getOutermostArraySize()));
        TType arrayElementType = getType();
        arrayElementType.toArrayElementType();
        size_t arrayElementSize = arrayElementType.getObjectSize();
        return &mUnionArrayPointer[arrayElementSize * index];
    }
    else if (isMatrix())
    {
        ASSERT(index < getType().getCols());
        int size = getType().getRows();
        return &mUnionArrayPointer[size * index];
    }
    else if (isVector())
    {
        ASSERT(index < getType().getNominalSize());
        return &mUnionArrayPointer[index];
    }
    else
    {
        UNREACHABLE();
        return nullptr;
    }
}

TIntermTyped *TIntermSwizzle::fold()
{
    TIntermConstantUnion *operandConstant = mOperand->getAsConstantUnion();
    if (operandConstant == nullptr)
    {
        return this;
    }

    TConstantUnion *constArray = new TConstantUnion[mSwizzleOffsets.size()];
    for (size_t i = 0; i < mSwizzleOffsets.size(); ++i)
    {
        constArray[i] = *operandConstant->foldIndexing(mSwizzleOffsets.at(i));
    }
    return CreateFoldedNode(constArray, this, mType.getQualifier());
}

TIntermTyped *TIntermBinary::fold(TDiagnostics *diagnostics)
{
    TIntermConstantUnion *leftConstant  = mLeft->getAsConstantUnion();
    TIntermConstantUnion *rightConstant = mRight->getAsConstantUnion();
    switch (mOp)
    {
        case EOpComma:
        {
            if (mLeft->hasSideEffects())
            {
                return this;
            }
            mRight->getTypePointer()->setQualifier(mType.getQualifier());
            return mRight;
        }
        case EOpIndexDirect:
        {
            if (leftConstant == nullptr || rightConstant == nullptr)
            {
                return this;
            }
            int index = rightConstant->getIConst(0);

            const TConstantUnion *constArray = leftConstant->foldIndexing(index);
            if (!constArray)
            {
                return this;
            }
            return CreateFoldedNode(constArray, this, mType.getQualifier());
        }
        case EOpIndexDirectStruct:
        {
            if (leftConstant == nullptr || rightConstant == nullptr)
            {
                return this;
            }
            const TFieldList &fields = mLeft->getType().getStruct()->fields();
            size_t index             = static_cast<size_t>(rightConstant->getIConst(0));

            size_t previousFieldsSize = 0;
            for (size_t i = 0; i < index; ++i)
            {
                previousFieldsSize += fields[i]->type()->getObjectSize();
            }

            const TConstantUnion *constArray = leftConstant->getUnionArrayPointer();
            return CreateFoldedNode(constArray + previousFieldsSize, this, mType.getQualifier());
        }
        case EOpIndexIndirect:
        case EOpIndexDirectInterfaceBlock:
            // Can never be constant folded.
            return this;
        default:
        {
            if (leftConstant == nullptr || rightConstant == nullptr)
            {
                return this;
            }
            TConstantUnion *constArray =
                leftConstant->foldBinary(mOp, rightConstant, diagnostics, mLeft->getLine());
            if (!constArray)
            {
                return this;
            }

            // Nodes may be constant folded without being qualified as constant.
            return CreateFoldedNode(constArray, this, mType.getQualifier());
        }
    }
}

TIntermTyped *TIntermUnary::fold(TDiagnostics *diagnostics)
{
    TConstantUnion *constArray = nullptr;

    if (mOp == EOpArrayLength)
    {
        if (mOperand->hasSideEffects())
        {
            return this;
        }
        constArray = new TConstantUnion[1];
        constArray->setIConst(mOperand->getOutermostArraySize());
    }
    else
    {
        TIntermConstantUnion *operandConstant = mOperand->getAsConstantUnion();
        if (operandConstant == nullptr)
        {
            return this;
        }

        switch (mOp)
        {
            case EOpAny:
            case EOpAll:
            case EOpLength:
            case EOpTranspose:
            case EOpDeterminant:
            case EOpInverse:
            case EOpPackSnorm2x16:
            case EOpUnpackSnorm2x16:
            case EOpPackUnorm2x16:
            case EOpUnpackUnorm2x16:
            case EOpPackHalf2x16:
            case EOpUnpackHalf2x16:
            case EOpPackUnorm4x8:
            case EOpPackSnorm4x8:
            case EOpUnpackUnorm4x8:
            case EOpUnpackSnorm4x8:
                constArray = operandConstant->foldUnaryNonComponentWise(mOp);
                break;
            default:
                constArray = operandConstant->foldUnaryComponentWise(mOp, diagnostics);
                break;
        }
    }
    if (constArray == nullptr)
    {
        return this;
    }

    // Nodes may be constant folded without being qualified as constant.
    return CreateFoldedNode(constArray, this, mType.getQualifier());
}

TIntermTyped *TIntermAggregate::fold(TDiagnostics *diagnostics)
{
    // Make sure that all params are constant before actual constant folding.
    for (auto *param : *getSequence())
    {
        if (param->getAsConstantUnion() == nullptr)
        {
            return this;
        }
    }
    TConstantUnion *constArray = nullptr;
    if (isConstructor())
        constArray = TIntermConstantUnion::FoldAggregateConstructor(this);
    else
        constArray = TIntermConstantUnion::FoldAggregateBuiltIn(this, diagnostics);

    // Nodes may be constant folded without being qualified as constant.
    return CreateFoldedNode(constArray, this, getQualifier());
}

//
// The fold functions see if an operation on a constant can be done in place,
// without generating run-time code.
//
// Returns the constant value to keep using or nullptr.
//
TConstantUnion *TIntermConstantUnion::foldBinary(TOperator op,
                                                 TIntermConstantUnion *rightNode,
                                                 TDiagnostics *diagnostics,
                                                 const TSourceLoc &line)
{
    const TConstantUnion *leftArray  = getUnionArrayPointer();
    const TConstantUnion *rightArray = rightNode->getUnionArrayPointer();

    ASSERT(leftArray && rightArray);

    size_t objectSize = getType().getObjectSize();

    // for a case like float f = vec4(2, 3, 4, 5) + 1.2;
    if (rightNode->getType().getObjectSize() == 1 && objectSize > 1)
    {
        rightArray = Vectorize(*rightNode->getUnionArrayPointer(), objectSize);
    }
    else if (rightNode->getType().getObjectSize() > 1 && objectSize == 1)
    {
        // for a case like float f = 1.2 + vec4(2, 3, 4, 5);
        leftArray  = Vectorize(*getUnionArrayPointer(), rightNode->getType().getObjectSize());
        objectSize = rightNode->getType().getObjectSize();
    }

    TConstantUnion *resultArray = nullptr;

    switch (op)
    {
        case EOpAdd:
            resultArray = new TConstantUnion[objectSize];
            for (size_t i = 0; i < objectSize; i++)
                resultArray[i] =
                    TConstantUnion::add(leftArray[i], rightArray[i], diagnostics, line);
            break;
        case EOpSub:
            resultArray = new TConstantUnion[objectSize];
            for (size_t i = 0; i < objectSize; i++)
                resultArray[i] =
                    TConstantUnion::sub(leftArray[i], rightArray[i], diagnostics, line);
            break;

        case EOpMul:
        case EOpVectorTimesScalar:
        case EOpMatrixTimesScalar:
            resultArray = new TConstantUnion[objectSize];
            for (size_t i = 0; i < objectSize; i++)
                resultArray[i] =
                    TConstantUnion::mul(leftArray[i], rightArray[i], diagnostics, line);
            break;

        case EOpMatrixTimesMatrix:
        {
            // TODO(jmadll): This code should check for overflows.
            ASSERT(getType().getBasicType() == EbtFloat && rightNode->getBasicType() == EbtFloat);

            const int leftCols   = getCols();
            const int leftRows   = getRows();
            const int rightCols  = rightNode->getType().getCols();
            const int rightRows  = rightNode->getType().getRows();
            const int resultCols = rightCols;
            const int resultRows = leftRows;

            resultArray = new TConstantUnion[resultCols * resultRows];
            for (int row = 0; row < resultRows; row++)
            {
                for (int column = 0; column < resultCols; column++)
                {
                    resultArray[resultRows * column + row].setFConst(0.0f);
                    for (int i = 0; i < leftCols; i++)
                    {
                        resultArray[resultRows * column + row].setFConst(
                            resultArray[resultRows * column + row].getFConst() +
                            leftArray[i * leftRows + row].getFConst() *
                                rightArray[column * rightRows + i].getFConst());
                    }
                }
            }
        }
        break;

        case EOpDiv:
        case EOpIMod:
        {
            resultArray = new TConstantUnion[objectSize];
            for (size_t i = 0; i < objectSize; i++)
            {
                switch (getType().getBasicType())
                {
                    case EbtFloat:
                    {
                        ASSERT(op == EOpDiv);
                        float dividend = leftArray[i].getFConst();
                        float divisor  = rightArray[i].getFConst();
                        if (divisor == 0.0f)
                        {
                            if (dividend == 0.0f)
                            {
                                diagnostics->warning(
                                    getLine(),
                                    "Zero divided by zero during constant folding generated NaN",
                                    "/");
                                resultArray[i].setFConst(std::numeric_limits<float>::quiet_NaN());
                            }
                            else
                            {
                                diagnostics->warning(getLine(),
                                                     "Divide by zero during constant folding", "/");
                                bool negativeResult =
                                    std::signbit(dividend) != std::signbit(divisor);
                                resultArray[i].setFConst(
                                    negativeResult ? -std::numeric_limits<float>::infinity()
                                                   : std::numeric_limits<float>::infinity());
                            }
                        }
                        else if (gl::isInf(dividend) && gl::isInf(divisor))
                        {
                            diagnostics->warning(getLine(),
                                                 "Infinity divided by infinity during constant "
                                                 "folding generated NaN",
                                                 "/");
                            resultArray[i].setFConst(std::numeric_limits<float>::quiet_NaN());
                        }
                        else
                        {
                            float result = dividend / divisor;
                            if (!gl::isInf(dividend) && gl::isInf(result))
                            {
                                diagnostics->warning(
                                    getLine(), "Constant folded division overflowed to infinity",
                                    "/");
                            }
                            resultArray[i].setFConst(result);
                        }
                        break;
                    }
                    case EbtInt:
                        if (rightArray[i] == 0)
                        {
                            diagnostics->warning(
                                getLine(), "Divide by zero error during constant folding", "/");
                            resultArray[i].setIConst(INT_MAX);
                        }
                        else
                        {
                            int lhs     = leftArray[i].getIConst();
                            int divisor = rightArray[i].getIConst();
                            if (op == EOpDiv)
                            {
                                // Check for the special case where the minimum representable number
                                // is
                                // divided by -1. If left alone this leads to integer overflow in
                                // C++.
                                // ESSL 3.00.6 section 4.1.3 Integers:
                                // "However, for the case where the minimum representable value is
                                // divided by -1, it is allowed to return either the minimum
                                // representable value or the maximum representable value."
                                if (lhs == -0x7fffffff - 1 && divisor == -1)
                                {
                                    resultArray[i].setIConst(0x7fffffff);
                                }
                                else
                                {
                                    resultArray[i].setIConst(lhs / divisor);
                                }
                            }
                            else
                            {
                                ASSERT(op == EOpIMod);
                                if (lhs < 0 || divisor < 0)
                                {
                                    // ESSL 3.00.6 section 5.9: Results of modulus are undefined
                                    // when
                                    // either one of the operands is negative.
                                    diagnostics->warning(getLine(),
                                                         "Negative modulus operator operand "
                                                         "encountered during constant folding",
                                                         "%");
                                    resultArray[i].setIConst(0);
                                }
                                else
                                {
                                    resultArray[i].setIConst(lhs % divisor);
                                }
                            }
                        }
                        break;

                    case EbtUInt:
                        if (rightArray[i] == 0)
                        {
                            diagnostics->warning(
                                getLine(), "Divide by zero error during constant folding", "/");
                            resultArray[i].setUConst(UINT_MAX);
                        }
                        else
                        {
                            if (op == EOpDiv)
                            {
                                resultArray[i].setUConst(leftArray[i].getUConst() /
                                                         rightArray[i].getUConst());
                            }
                            else
                            {
                                ASSERT(op == EOpIMod);
                                resultArray[i].setUConst(leftArray[i].getUConst() %
                                                         rightArray[i].getUConst());
                            }
                        }
                        break;

                    default:
                        UNREACHABLE();
                        return nullptr;
                }
            }
        }
        break;

        case EOpMatrixTimesVector:
        {
            // TODO(jmadll): This code should check for overflows.
            ASSERT(rightNode->getBasicType() == EbtFloat);

            const int matrixCols = getCols();
            const int matrixRows = getRows();

            resultArray = new TConstantUnion[matrixRows];

            for (int matrixRow = 0; matrixRow < matrixRows; matrixRow++)
            {
                resultArray[matrixRow].setFConst(0.0f);
                for (int col = 0; col < matrixCols; col++)
                {
                    resultArray[matrixRow].setFConst(
                        resultArray[matrixRow].getFConst() +
                        leftArray[col * matrixRows + matrixRow].getFConst() *
                            rightArray[col].getFConst());
                }
            }
        }
        break;

        case EOpVectorTimesMatrix:
        {
            // TODO(jmadll): This code should check for overflows.
            ASSERT(getType().getBasicType() == EbtFloat);

            const int matrixCols = rightNode->getType().getCols();
            const int matrixRows = rightNode->getType().getRows();

            resultArray = new TConstantUnion[matrixCols];

            for (int matrixCol = 0; matrixCol < matrixCols; matrixCol++)
            {
                resultArray[matrixCol].setFConst(0.0f);
                for (int matrixRow = 0; matrixRow < matrixRows; matrixRow++)
                {
                    resultArray[matrixCol].setFConst(
                        resultArray[matrixCol].getFConst() +
                        leftArray[matrixRow].getFConst() *
                            rightArray[matrixCol * matrixRows + matrixRow].getFConst());
                }
            }
        }
        break;

        case EOpLogicalAnd:
        {
            resultArray = new TConstantUnion[objectSize];
            for (size_t i = 0; i < objectSize; i++)
            {
                resultArray[i] = leftArray[i] && rightArray[i];
            }
        }
        break;

        case EOpLogicalOr:
        {
            resultArray = new TConstantUnion[objectSize];
            for (size_t i = 0; i < objectSize; i++)
            {
                resultArray[i] = leftArray[i] || rightArray[i];
            }
        }
        break;

        case EOpLogicalXor:
        {
            ASSERT(getType().getBasicType() == EbtBool);
            resultArray = new TConstantUnion[objectSize];
            for (size_t i = 0; i < objectSize; i++)
            {
                resultArray[i].setBConst(leftArray[i] != rightArray[i]);
            }
        }
        break;

        case EOpBitwiseAnd:
            resultArray = new TConstantUnion[objectSize];
            for (size_t i      = 0; i < objectSize; i++)
                resultArray[i] = leftArray[i] & rightArray[i];
            break;
        case EOpBitwiseXor:
            resultArray = new TConstantUnion[objectSize];
            for (size_t i      = 0; i < objectSize; i++)
                resultArray[i] = leftArray[i] ^ rightArray[i];
            break;
        case EOpBitwiseOr:
            resultArray = new TConstantUnion[objectSize];
            for (size_t i      = 0; i < objectSize; i++)
                resultArray[i] = leftArray[i] | rightArray[i];
            break;
        case EOpBitShiftLeft:
            resultArray = new TConstantUnion[objectSize];
            for (size_t i = 0; i < objectSize; i++)
                resultArray[i] =
                    TConstantUnion::lshift(leftArray[i], rightArray[i], diagnostics, line);
            break;
        case EOpBitShiftRight:
            resultArray = new TConstantUnion[objectSize];
            for (size_t i = 0; i < objectSize; i++)
                resultArray[i] =
                    TConstantUnion::rshift(leftArray[i], rightArray[i], diagnostics, line);
            break;

        case EOpLessThan:
            ASSERT(objectSize == 1);
            resultArray = new TConstantUnion[1];
            resultArray->setBConst(*leftArray < *rightArray);
            break;

        case EOpGreaterThan:
            ASSERT(objectSize == 1);
            resultArray = new TConstantUnion[1];
            resultArray->setBConst(*leftArray > *rightArray);
            break;

        case EOpLessThanEqual:
            ASSERT(objectSize == 1);
            resultArray = new TConstantUnion[1];
            resultArray->setBConst(!(*leftArray > *rightArray));
            break;

        case EOpGreaterThanEqual:
            ASSERT(objectSize == 1);
            resultArray = new TConstantUnion[1];
            resultArray->setBConst(!(*leftArray < *rightArray));
            break;

        case EOpEqual:
        case EOpNotEqual:
        {
            resultArray = new TConstantUnion[1];
            bool equal  = true;
            for (size_t i = 0; i < objectSize; i++)
            {
                if (leftArray[i] != rightArray[i])
                {
                    equal = false;
                    break;  // break out of for loop
                }
            }
            if (op == EOpEqual)
            {
                resultArray->setBConst(equal);
            }
            else
            {
                resultArray->setBConst(!equal);
            }
        }
        break;

        default:
            UNREACHABLE();
            return nullptr;
    }
    return resultArray;
}

// The fold functions do operations on a constant at GLSL compile time, without generating run-time
// code. Returns the constant value to keep using. Nullptr should not be returned.
TConstantUnion *TIntermConstantUnion::foldUnaryNonComponentWise(TOperator op)
{
    // Do operations where the return type may have a different number of components compared to the
    // operand type.

    const TConstantUnion *operandArray = getUnionArrayPointer();
    ASSERT(operandArray);

    size_t objectSize           = getType().getObjectSize();
    TConstantUnion *resultArray = nullptr;
    switch (op)
    {
        case EOpAny:
            ASSERT(getType().getBasicType() == EbtBool);
            resultArray = new TConstantUnion();
            resultArray->setBConst(false);
            for (size_t i = 0; i < objectSize; i++)
            {
                if (operandArray[i].getBConst())
                {
                    resultArray->setBConst(true);
                    break;
                }
            }
            break;

        case EOpAll:
            ASSERT(getType().getBasicType() == EbtBool);
            resultArray = new TConstantUnion();
            resultArray->setBConst(true);
            for (size_t i = 0; i < objectSize; i++)
            {
                if (!operandArray[i].getBConst())
                {
                    resultArray->setBConst(false);
                    break;
                }
            }
            break;

        case EOpLength:
            ASSERT(getType().getBasicType() == EbtFloat);
            resultArray = new TConstantUnion();
            resultArray->setFConst(VectorLength(operandArray, objectSize));
            break;

        case EOpTranspose:
        {
            ASSERT(getType().getBasicType() == EbtFloat);
            resultArray = new TConstantUnion[objectSize];
            angle::Matrix<float> result =
                GetMatrix(operandArray, getType().getRows(), getType().getCols()).transpose();
            SetUnionArrayFromMatrix(result, resultArray);
            break;
        }

        case EOpDeterminant:
        {
            ASSERT(getType().getBasicType() == EbtFloat);
            unsigned int size = getType().getNominalSize();
            ASSERT(size >= 2 && size <= 4);
            resultArray = new TConstantUnion();
            resultArray->setFConst(GetMatrix(operandArray, size).determinant());
            break;
        }

        case EOpInverse:
        {
            ASSERT(getType().getBasicType() == EbtFloat);
            unsigned int size = getType().getNominalSize();
            ASSERT(size >= 2 && size <= 4);
            resultArray                 = new TConstantUnion[objectSize];
            angle::Matrix<float> result = GetMatrix(operandArray, size).inverse();
            SetUnionArrayFromMatrix(result, resultArray);
            break;
        }

        case EOpPackSnorm2x16:
            ASSERT(getType().getBasicType() == EbtFloat);
            ASSERT(getType().getNominalSize() == 2);
            resultArray = new TConstantUnion();
            resultArray->setUConst(
                gl::packSnorm2x16(operandArray[0].getFConst(), operandArray[1].getFConst()));
            break;

        case EOpUnpackSnorm2x16:
        {
            ASSERT(getType().getBasicType() == EbtUInt);
            resultArray = new TConstantUnion[2];
            float f1, f2;
            gl::unpackSnorm2x16(operandArray[0].getUConst(), &f1, &f2);
            resultArray[0].setFConst(f1);
            resultArray[1].setFConst(f2);
            break;
        }

        case EOpPackUnorm2x16:
            ASSERT(getType().getBasicType() == EbtFloat);
            ASSERT(getType().getNominalSize() == 2);
            resultArray = new TConstantUnion();
            resultArray->setUConst(
                gl::packUnorm2x16(operandArray[0].getFConst(), operandArray[1].getFConst()));
            break;

        case EOpUnpackUnorm2x16:
        {
            ASSERT(getType().getBasicType() == EbtUInt);
            resultArray = new TConstantUnion[2];
            float f1, f2;
            gl::unpackUnorm2x16(operandArray[0].getUConst(), &f1, &f2);
            resultArray[0].setFConst(f1);
            resultArray[1].setFConst(f2);
            break;
        }

        case EOpPackHalf2x16:
            ASSERT(getType().getBasicType() == EbtFloat);
            ASSERT(getType().getNominalSize() == 2);
            resultArray = new TConstantUnion();
            resultArray->setUConst(
                gl::packHalf2x16(operandArray[0].getFConst(), operandArray[1].getFConst()));
            break;

        case EOpUnpackHalf2x16:
        {
            ASSERT(getType().getBasicType() == EbtUInt);
            resultArray = new TConstantUnion[2];
            float f1, f2;
            gl::unpackHalf2x16(operandArray[0].getUConst(), &f1, &f2);
            resultArray[0].setFConst(f1);
            resultArray[1].setFConst(f2);
            break;
        }

        case EOpPackUnorm4x8:
        {
            ASSERT(getType().getBasicType() == EbtFloat);
            resultArray = new TConstantUnion();
            resultArray->setUConst(
                gl::PackUnorm4x8(operandArray[0].getFConst(), operandArray[1].getFConst(),
                                 operandArray[2].getFConst(), operandArray[3].getFConst()));
            break;
        }
        case EOpPackSnorm4x8:
        {
            ASSERT(getType().getBasicType() == EbtFloat);
            resultArray = new TConstantUnion();
            resultArray->setUConst(
                gl::PackSnorm4x8(operandArray[0].getFConst(), operandArray[1].getFConst(),
                                 operandArray[2].getFConst(), operandArray[3].getFConst()));
            break;
        }
        case EOpUnpackUnorm4x8:
        {
            ASSERT(getType().getBasicType() == EbtUInt);
            resultArray = new TConstantUnion[4];
            float f[4];
            gl::UnpackUnorm4x8(operandArray[0].getUConst(), f);
            for (size_t i = 0; i < 4; ++i)
            {
                resultArray[i].setFConst(f[i]);
            }
            break;
        }
        case EOpUnpackSnorm4x8:
        {
            ASSERT(getType().getBasicType() == EbtUInt);
            resultArray = new TConstantUnion[4];
            float f[4];
            gl::UnpackSnorm4x8(operandArray[0].getUConst(), f);
            for (size_t i = 0; i < 4; ++i)
            {
                resultArray[i].setFConst(f[i]);
            }
            break;
        }

        default:
            UNREACHABLE();
            break;
    }

    return resultArray;
}

TConstantUnion *TIntermConstantUnion::foldUnaryComponentWise(TOperator op,
                                                             TDiagnostics *diagnostics)
{
    // Do unary operations where each component of the result is computed based on the corresponding
    // component of the operand. Also folds normalize, though the divisor in that case takes all
    // components into account.

    const TConstantUnion *operandArray = getUnionArrayPointer();
    ASSERT(operandArray);

    size_t objectSize = getType().getObjectSize();

    TConstantUnion *resultArray = new TConstantUnion[objectSize];
    for (size_t i = 0; i < objectSize; i++)
    {
        switch (op)
        {
            case EOpNegative:
                switch (getType().getBasicType())
                {
                    case EbtFloat:
                        resultArray[i].setFConst(-operandArray[i].getFConst());
                        break;
                    case EbtInt:
                        if (operandArray[i] == std::numeric_limits<int>::min())
                        {
                            // The minimum representable integer doesn't have a positive
                            // counterpart, rather the negation overflows and in ESSL is supposed to
                            // wrap back to the minimum representable integer. Make sure that we
                            // don't actually let the negation overflow, which has undefined
                            // behavior in C++.
                            resultArray[i].setIConst(std::numeric_limits<int>::min());
                        }
                        else
                        {
                            resultArray[i].setIConst(-operandArray[i].getIConst());
                        }
                        break;
                    case EbtUInt:
                        if (operandArray[i] == 0x80000000u)
                        {
                            resultArray[i].setUConst(0x80000000u);
                        }
                        else
                        {
                            resultArray[i].setUConst(static_cast<unsigned int>(
                                -static_cast<int>(operandArray[i].getUConst())));
                        }
                        break;
                    default:
                        UNREACHABLE();
                        return nullptr;
                }
                break;

            case EOpPositive:
                switch (getType().getBasicType())
                {
                    case EbtFloat:
                        resultArray[i].setFConst(operandArray[i].getFConst());
                        break;
                    case EbtInt:
                        resultArray[i].setIConst(operandArray[i].getIConst());
                        break;
                    case EbtUInt:
                        resultArray[i].setUConst(static_cast<unsigned int>(
                            static_cast<int>(operandArray[i].getUConst())));
                        break;
                    default:
                        UNREACHABLE();
                        return nullptr;
                }
                break;

            case EOpLogicalNot:
                switch (getType().getBasicType())
                {
                    case EbtBool:
                        resultArray[i].setBConst(!operandArray[i].getBConst());
                        break;
                    default:
                        UNREACHABLE();
                        return nullptr;
                }
                break;

            case EOpBitwiseNot:
                switch (getType().getBasicType())
                {
                    case EbtInt:
                        resultArray[i].setIConst(~operandArray[i].getIConst());
                        break;
                    case EbtUInt:
                        resultArray[i].setUConst(~operandArray[i].getUConst());
                        break;
                    default:
                        UNREACHABLE();
                        return nullptr;
                }
                break;

            case EOpRadians:
                ASSERT(getType().getBasicType() == EbtFloat);
                resultArray[i].setFConst(kDegreesToRadiansMultiplier * operandArray[i].getFConst());
                break;

            case EOpDegrees:
                ASSERT(getType().getBasicType() == EbtFloat);
                resultArray[i].setFConst(kRadiansToDegreesMultiplier * operandArray[i].getFConst());
                break;

            case EOpSin:
                foldFloatTypeUnary(operandArray[i], &sinf, &resultArray[i]);
                break;

            case EOpCos:
                foldFloatTypeUnary(operandArray[i], &cosf, &resultArray[i]);
                break;

            case EOpTan:
                foldFloatTypeUnary(operandArray[i], &tanf, &resultArray[i]);
                break;

            case EOpAsin:
                // For asin(x), results are undefined if |x| > 1, we are choosing to set result to
                // 0.
                if (fabsf(operandArray[i].getFConst()) > 1.0f)
                    UndefinedConstantFoldingError(getLine(), op, getType().getBasicType(),
                                                  diagnostics, &resultArray[i]);
                else
                    foldFloatTypeUnary(operandArray[i], &asinf, &resultArray[i]);
                break;

            case EOpAcos:
                // For acos(x), results are undefined if |x| > 1, we are choosing to set result to
                // 0.
                if (fabsf(operandArray[i].getFConst()) > 1.0f)
                    UndefinedConstantFoldingError(getLine(), op, getType().getBasicType(),
                                                  diagnostics, &resultArray[i]);
                else
                    foldFloatTypeUnary(operandArray[i], &acosf, &resultArray[i]);
                break;

            case EOpAtan:
                foldFloatTypeUnary(operandArray[i], &atanf, &resultArray[i]);
                break;

            case EOpSinh:
                foldFloatTypeUnary(operandArray[i], &sinhf, &resultArray[i]);
                break;

            case EOpCosh:
                foldFloatTypeUnary(operandArray[i], &coshf, &resultArray[i]);
                break;

            case EOpTanh:
                foldFloatTypeUnary(operandArray[i], &tanhf, &resultArray[i]);
                break;

            case EOpAsinh:
                foldFloatTypeUnary(operandArray[i], &asinhf, &resultArray[i]);
                break;

            case EOpAcosh:
                // For acosh(x), results are undefined if x < 1, we are choosing to set result to 0.
                if (operandArray[i].getFConst() < 1.0f)
                    UndefinedConstantFoldingError(getLine(), op, getType().getBasicType(),
                                                  diagnostics, &resultArray[i]);
                else
                    foldFloatTypeUnary(operandArray[i], &acoshf, &resultArray[i]);
                break;

            case EOpAtanh:
                // For atanh(x), results are undefined if |x| >= 1, we are choosing to set result to
                // 0.
                if (fabsf(operandArray[i].getFConst()) >= 1.0f)
                    UndefinedConstantFoldingError(getLine(), op, getType().getBasicType(),
                                                  diagnostics, &resultArray[i]);
                else
                    foldFloatTypeUnary(operandArray[i], &atanhf, &resultArray[i]);
                break;

            case EOpAbs:
                switch (getType().getBasicType())
                {
                    case EbtFloat:
                        resultArray[i].setFConst(fabsf(operandArray[i].getFConst()));
                        break;
                    case EbtInt:
                        resultArray[i].setIConst(abs(operandArray[i].getIConst()));
                        break;
                    default:
                        UNREACHABLE();
                        return nullptr;
                }
                break;

            case EOpSign:
                switch (getType().getBasicType())
                {
                    case EbtFloat:
                    {
                        float fConst  = operandArray[i].getFConst();
                        float fResult = 0.0f;
                        if (fConst > 0.0f)
                            fResult = 1.0f;
                        else if (fConst < 0.0f)
                            fResult = -1.0f;
                        resultArray[i].setFConst(fResult);
                        break;
                    }
                    case EbtInt:
                    {
                        int iConst  = operandArray[i].getIConst();
                        int iResult = 0;
                        if (iConst > 0)
                            iResult = 1;
                        else if (iConst < 0)
                            iResult = -1;
                        resultArray[i].setIConst(iResult);
                        break;
                    }
                    default:
                        UNREACHABLE();
                        return nullptr;
                }
                break;

            case EOpFloor:
                foldFloatTypeUnary(operandArray[i], &floorf, &resultArray[i]);
                break;

            case EOpTrunc:
                foldFloatTypeUnary(operandArray[i], &truncf, &resultArray[i]);
                break;

            case EOpRound:
                foldFloatTypeUnary(operandArray[i], &roundf, &resultArray[i]);
                break;

            case EOpRoundEven:
            {
                ASSERT(getType().getBasicType() == EbtFloat);
                float x = operandArray[i].getFConst();
                float result;
                float fractPart = modff(x, &result);
                if (fabsf(fractPart) == 0.5f)
                    result = 2.0f * roundf(x / 2.0f);
                else
                    result = roundf(x);
                resultArray[i].setFConst(result);
                break;
            }

            case EOpCeil:
                foldFloatTypeUnary(operandArray[i], &ceilf, &resultArray[i]);
                break;

            case EOpFract:
            {
                ASSERT(getType().getBasicType() == EbtFloat);
                float x = operandArray[i].getFConst();
                resultArray[i].setFConst(x - floorf(x));
                break;
            }

            case EOpIsNan:
                ASSERT(getType().getBasicType() == EbtFloat);
                resultArray[i].setBConst(gl::isNaN(operandArray[0].getFConst()));
                break;

            case EOpIsInf:
                ASSERT(getType().getBasicType() == EbtFloat);
                resultArray[i].setBConst(gl::isInf(operandArray[0].getFConst()));
                break;

            case EOpFloatBitsToInt:
                ASSERT(getType().getBasicType() == EbtFloat);
                resultArray[i].setIConst(gl::bitCast<int32_t>(operandArray[0].getFConst()));
                break;

            case EOpFloatBitsToUint:
                ASSERT(getType().getBasicType() == EbtFloat);
                resultArray[i].setUConst(gl::bitCast<uint32_t>(operandArray[0].getFConst()));
                break;

            case EOpIntBitsToFloat:
                ASSERT(getType().getBasicType() == EbtInt);
                resultArray[i].setFConst(gl::bitCast<float>(operandArray[0].getIConst()));
                break;

            case EOpUintBitsToFloat:
                ASSERT(getType().getBasicType() == EbtUInt);
                resultArray[i].setFConst(gl::bitCast<float>(operandArray[0].getUConst()));
                break;

            case EOpExp:
                foldFloatTypeUnary(operandArray[i], &expf, &resultArray[i]);
                break;

            case EOpLog:
                // For log(x), results are undefined if x <= 0, we are choosing to set result to 0.
                if (operandArray[i].getFConst() <= 0.0f)
                    UndefinedConstantFoldingError(getLine(), op, getType().getBasicType(),
                                                  diagnostics, &resultArray[i]);
                else
                    foldFloatTypeUnary(operandArray[i], &logf, &resultArray[i]);
                break;

            case EOpExp2:
                foldFloatTypeUnary(operandArray[i], &exp2f, &resultArray[i]);
                break;

            case EOpLog2:
                // For log2(x), results are undefined if x <= 0, we are choosing to set result to 0.
                // And log2f is not available on some plarforms like old android, so just using
                // log(x)/log(2) here.
                if (operandArray[i].getFConst() <= 0.0f)
                    UndefinedConstantFoldingError(getLine(), op, getType().getBasicType(),
                                                  diagnostics, &resultArray[i]);
                else
                {
                    foldFloatTypeUnary(operandArray[i], &logf, &resultArray[i]);
                    resultArray[i].setFConst(resultArray[i].getFConst() / logf(2.0f));
                }
                break;

            case EOpSqrt:
                // For sqrt(x), results are undefined if x < 0, we are choosing to set result to 0.
                if (operandArray[i].getFConst() < 0.0f)
                    UndefinedConstantFoldingError(getLine(), op, getType().getBasicType(),
                                                  diagnostics, &resultArray[i]);
                else
                    foldFloatTypeUnary(operandArray[i], &sqrtf, &resultArray[i]);
                break;

            case EOpInverseSqrt:
                // There is no stdlib built-in function equavalent for GLES built-in inversesqrt(),
                // so getting the square root first using builtin function sqrt() and then taking
                // its inverse.
                // Also, for inversesqrt(x), results are undefined if x <= 0, we are choosing to set
                // result to 0.
                if (operandArray[i].getFConst() <= 0.0f)
                    UndefinedConstantFoldingError(getLine(), op, getType().getBasicType(),
                                                  diagnostics, &resultArray[i]);
                else
                {
                    foldFloatTypeUnary(operandArray[i], &sqrtf, &resultArray[i]);
                    resultArray[i].setFConst(1.0f / resultArray[i].getFConst());
                }
                break;

            case EOpLogicalNotComponentWise:
                ASSERT(getType().getBasicType() == EbtBool);
                resultArray[i].setBConst(!operandArray[i].getBConst());
                break;

            case EOpNormalize:
            {
                ASSERT(getType().getBasicType() == EbtFloat);
                float x      = operandArray[i].getFConst();
                float length = VectorLength(operandArray, objectSize);
                if (length)
                    resultArray[i].setFConst(x / length);
                else
                    UndefinedConstantFoldingError(getLine(), op, getType().getBasicType(),
                                                  diagnostics, &resultArray[i]);
                break;
            }
            case EOpBitfieldReverse:
            {
                uint32_t value;
                if (getType().getBasicType() == EbtInt)
                {
                    value = static_cast<uint32_t>(operandArray[i].getIConst());
                }
                else
                {
                    ASSERT(getType().getBasicType() == EbtUInt);
                    value = operandArray[i].getUConst();
                }
                uint32_t result = gl::BitfieldReverse(value);
                if (getType().getBasicType() == EbtInt)
                {
                    resultArray[i].setIConst(static_cast<int32_t>(result));
                }
                else
                {
                    resultArray[i].setUConst(result);
                }
                break;
            }
            case EOpBitCount:
            {
                uint32_t value;
                if (getType().getBasicType() == EbtInt)
                {
                    value = static_cast<uint32_t>(operandArray[i].getIConst());
                }
                else
                {
                    ASSERT(getType().getBasicType() == EbtUInt);
                    value = operandArray[i].getUConst();
                }
                int result = gl::BitCount(value);
                resultArray[i].setIConst(result);
                break;
            }
            case EOpFindLSB:
            {
                uint32_t value;
                if (getType().getBasicType() == EbtInt)
                {
                    value = static_cast<uint32_t>(operandArray[i].getIConst());
                }
                else
                {
                    ASSERT(getType().getBasicType() == EbtUInt);
                    value = operandArray[i].getUConst();
                }
                resultArray[i].setIConst(gl::FindLSB(value));
                break;
            }
            case EOpFindMSB:
            {
                uint32_t value;
                if (getType().getBasicType() == EbtInt)
                {
                    int intValue = operandArray[i].getIConst();
                    value        = static_cast<uint32_t>(intValue);
                    if (intValue < 0)
                    {
                        // Look for zero instead of one in value. This also handles the intValue ==
                        // -1 special case, where the return value needs to be -1.
                        value = ~value;
                    }
                }
                else
                {
                    ASSERT(getType().getBasicType() == EbtUInt);
                    value = operandArray[i].getUConst();
                }
                resultArray[i].setIConst(gl::FindMSB(value));
                break;
            }
            case EOpDFdx:
            case EOpDFdy:
            case EOpFwidth:
                ASSERT(getType().getBasicType() == EbtFloat);
                // Derivatives of constant arguments should be 0.
                resultArray[i].setFConst(0.0f);
                break;

            default:
                return nullptr;
        }
    }

    return resultArray;
}

void TIntermConstantUnion::foldFloatTypeUnary(const TConstantUnion &parameter,
                                              FloatTypeUnaryFunc builtinFunc,
                                              TConstantUnion *result) const
{
    ASSERT(builtinFunc);

    ASSERT(getType().getBasicType() == EbtFloat);
    result->setFConst(builtinFunc(parameter.getFConst()));
}

// static
TConstantUnion *TIntermConstantUnion::FoldAggregateConstructor(TIntermAggregate *aggregate)
{
    ASSERT(aggregate->getSequence()->size() > 0u);
    size_t resultSize           = aggregate->getType().getObjectSize();
    TConstantUnion *resultArray = new TConstantUnion[resultSize];
    TBasicType basicType        = aggregate->getBasicType();

    size_t resultIndex = 0u;

    if (aggregate->getSequence()->size() == 1u)
    {
        TIntermNode *argument                    = aggregate->getSequence()->front();
        TIntermConstantUnion *argumentConstant   = argument->getAsConstantUnion();
        const TConstantUnion *argumentUnionArray = argumentConstant->getUnionArrayPointer();
        // Check the special case of constructing a matrix diagonal from a single scalar,
        // or a vector from a single scalar.
        if (argumentConstant->getType().getObjectSize() == 1u)
        {
            if (aggregate->isMatrix())
            {
                int resultCols = aggregate->getType().getCols();
                int resultRows = aggregate->getType().getRows();
                for (int col = 0; col < resultCols; ++col)
                {
                    for (int row = 0; row < resultRows; ++row)
                    {
                        if (col == row)
                        {
                            resultArray[resultIndex].cast(basicType, argumentUnionArray[0]);
                        }
                        else
                        {
                            resultArray[resultIndex].setFConst(0.0f);
                        }
                        ++resultIndex;
                    }
                }
            }
            else
            {
                while (resultIndex < resultSize)
                {
                    resultArray[resultIndex].cast(basicType, argumentUnionArray[0]);
                    ++resultIndex;
                }
            }
            ASSERT(resultIndex == resultSize);
            return resultArray;
        }
        else if (aggregate->isMatrix() && argumentConstant->isMatrix())
        {
            // The special case of constructing a matrix from a matrix.
            int argumentCols = argumentConstant->getType().getCols();
            int argumentRows = argumentConstant->getType().getRows();
            int resultCols   = aggregate->getType().getCols();
            int resultRows   = aggregate->getType().getRows();
            for (int col = 0; col < resultCols; ++col)
            {
                for (int row = 0; row < resultRows; ++row)
                {
                    if (col < argumentCols && row < argumentRows)
                    {
                        resultArray[resultIndex].cast(basicType,
                                                      argumentUnionArray[col * argumentRows + row]);
                    }
                    else if (col == row)
                    {
                        resultArray[resultIndex].setFConst(1.0f);
                    }
                    else
                    {
                        resultArray[resultIndex].setFConst(0.0f);
                    }
                    ++resultIndex;
                }
            }
            ASSERT(resultIndex == resultSize);
            return resultArray;
        }
    }

    for (TIntermNode *&argument : *aggregate->getSequence())
    {
        TIntermConstantUnion *argumentConstant   = argument->getAsConstantUnion();
        size_t argumentSize                      = argumentConstant->getType().getObjectSize();
        const TConstantUnion *argumentUnionArray = argumentConstant->getUnionArrayPointer();
        for (size_t i = 0u; i < argumentSize; ++i)
        {
            if (resultIndex >= resultSize)
                break;
            resultArray[resultIndex].cast(basicType, argumentUnionArray[i]);
            ++resultIndex;
        }
    }
    ASSERT(resultIndex == resultSize);
    return resultArray;
}

bool TIntermAggregate::CanFoldAggregateBuiltInOp(TOperator op)
{
    switch (op)
    {
        case EOpAtan:
        case EOpPow:
        case EOpMod:
        case EOpMin:
        case EOpMax:
        case EOpClamp:
        case EOpMix:
        case EOpStep:
        case EOpSmoothStep:
        case EOpLdexp:
        case EOpMulMatrixComponentWise:
        case EOpOuterProduct:
        case EOpEqualComponentWise:
        case EOpNotEqualComponentWise:
        case EOpLessThanComponentWise:
        case EOpLessThanEqualComponentWise:
        case EOpGreaterThanComponentWise:
        case EOpGreaterThanEqualComponentWise:
        case EOpDistance:
        case EOpDot:
        case EOpCross:
        case EOpFaceforward:
        case EOpReflect:
        case EOpRefract:
        case EOpBitfieldExtract:
        case EOpBitfieldInsert:
            return true;
        default:
            return false;
    }
}

// static
TConstantUnion *TIntermConstantUnion::FoldAggregateBuiltIn(TIntermAggregate *aggregate,
                                                           TDiagnostics *diagnostics)
{
    TOperator op              = aggregate->getOp();
    TIntermSequence *arguments = aggregate->getSequence();
    unsigned int argsCount     = static_cast<unsigned int>(arguments->size());
    std::vector<const TConstantUnion *> unionArrays(argsCount);
    std::vector<size_t> objectSizes(argsCount);
    size_t maxObjectSize = 0;
    TBasicType basicType = EbtVoid;
    TSourceLoc loc;
    for (unsigned int i = 0; i < argsCount; i++)
    {
        TIntermConstantUnion *argConstant = (*arguments)[i]->getAsConstantUnion();
        ASSERT(argConstant != nullptr);  // Should be checked already.

        if (i == 0)
        {
            basicType = argConstant->getType().getBasicType();
            loc       = argConstant->getLine();
        }
        unionArrays[i] = argConstant->getUnionArrayPointer();
        objectSizes[i] = argConstant->getType().getObjectSize();
        if (objectSizes[i] > maxObjectSize)
            maxObjectSize = objectSizes[i];
    }

    if (!(*arguments)[0]->getAsTyped()->isMatrix() && aggregate->getOp() != EOpOuterProduct)
    {
        for (unsigned int i = 0; i < argsCount; i++)
            if (objectSizes[i] != maxObjectSize)
                unionArrays[i] = Vectorize(*unionArrays[i], maxObjectSize);
    }

    TConstantUnion *resultArray = nullptr;

    switch (op)
    {
        case EOpAtan:
        {
            ASSERT(basicType == EbtFloat);
            resultArray = new TConstantUnion[maxObjectSize];
            for (size_t i = 0; i < maxObjectSize; i++)
            {
                float y = unionArrays[0][i].getFConst();
                float x = unionArrays[1][i].getFConst();
                // Results are undefined if x and y are both 0.
                if (x == 0.0f && y == 0.0f)
                    UndefinedConstantFoldingError(loc, op, basicType, diagnostics, &resultArray[i]);
                else
                    resultArray[i].setFConst(atan2f(y, x));
            }
            break;
        }

        case EOpPow:
        {
            ASSERT(basicType == EbtFloat);
            resultArray = new TConstantUnion[maxObjectSize];
            for (size_t i = 0; i < maxObjectSize; i++)
            {
                float x = unionArrays[0][i].getFConst();
                float y = unionArrays[1][i].getFConst();
                // Results are undefined if x < 0.
                // Results are undefined if x = 0 and y <= 0.
                if (x < 0.0f)
                    UndefinedConstantFoldingError(loc, op, basicType, diagnostics, &resultArray[i]);
                else if (x == 0.0f && y <= 0.0f)
                    UndefinedConstantFoldingError(loc, op, basicType, diagnostics, &resultArray[i]);
                else
                    resultArray[i].setFConst(powf(x, y));
            }
            break;
        }

        case EOpMod:
        {
            ASSERT(basicType == EbtFloat);
            resultArray = new TConstantUnion[maxObjectSize];
            for (size_t i = 0; i < maxObjectSize; i++)
            {
                float x = unionArrays[0][i].getFConst();
                float y = unionArrays[1][i].getFConst();
                resultArray[i].setFConst(x - y * floorf(x / y));
            }
            break;
        }

        case EOpMin:
        {
            resultArray = new TConstantUnion[maxObjectSize];
            for (size_t i = 0; i < maxObjectSize; i++)
            {
                switch (basicType)
                {
                    case EbtFloat:
                        resultArray[i].setFConst(
                            std::min(unionArrays[0][i].getFConst(), unionArrays[1][i].getFConst()));
                        break;
                    case EbtInt:
                        resultArray[i].setIConst(
                            std::min(unionArrays[0][i].getIConst(), unionArrays[1][i].getIConst()));
                        break;
                    case EbtUInt:
                        resultArray[i].setUConst(
                            std::min(unionArrays[0][i].getUConst(), unionArrays[1][i].getUConst()));
                        break;
                    default:
                        UNREACHABLE();
                        break;
                }
            }
            break;
        }

        case EOpMax:
        {
            resultArray = new TConstantUnion[maxObjectSize];
            for (size_t i = 0; i < maxObjectSize; i++)
            {
                switch (basicType)
                {
                    case EbtFloat:
                        resultArray[i].setFConst(
                            std::max(unionArrays[0][i].getFConst(), unionArrays[1][i].getFConst()));
                        break;
                    case EbtInt:
                        resultArray[i].setIConst(
                            std::max(unionArrays[0][i].getIConst(), unionArrays[1][i].getIConst()));
                        break;
                    case EbtUInt:
                        resultArray[i].setUConst(
                            std::max(unionArrays[0][i].getUConst(), unionArrays[1][i].getUConst()));
                        break;
                    default:
                        UNREACHABLE();
                        break;
                }
            }
            break;
        }

        case EOpStep:
        {
            ASSERT(basicType == EbtFloat);
            resultArray = new TConstantUnion[maxObjectSize];
            for (size_t i = 0; i < maxObjectSize; i++)
                resultArray[i].setFConst(
                    unionArrays[1][i].getFConst() < unionArrays[0][i].getFConst() ? 0.0f : 1.0f);
            break;
        }

        case EOpLessThanComponentWise:
        {
            resultArray = new TConstantUnion[maxObjectSize];
            for (size_t i = 0; i < maxObjectSize; i++)
            {
                switch (basicType)
                {
                    case EbtFloat:
                        resultArray[i].setBConst(unionArrays[0][i].getFConst() <
                                                 unionArrays[1][i].getFConst());
                        break;
                    case EbtInt:
                        resultArray[i].setBConst(unionArrays[0][i].getIConst() <
                                                 unionArrays[1][i].getIConst());
                        break;
                    case EbtUInt:
                        resultArray[i].setBConst(unionArrays[0][i].getUConst() <
                                                 unionArrays[1][i].getUConst());
                        break;
                    default:
                        UNREACHABLE();
                        break;
                }
            }
            break;
        }

        case EOpLessThanEqualComponentWise:
        {
            resultArray = new TConstantUnion[maxObjectSize];
            for (size_t i = 0; i < maxObjectSize; i++)
            {
                switch (basicType)
                {
                    case EbtFloat:
                        resultArray[i].setBConst(unionArrays[0][i].getFConst() <=
                                                 unionArrays[1][i].getFConst());
                        break;
                    case EbtInt:
                        resultArray[i].setBConst(unionArrays[0][i].getIConst() <=
                                                 unionArrays[1][i].getIConst());
                        break;
                    case EbtUInt:
                        resultArray[i].setBConst(unionArrays[0][i].getUConst() <=
                                                 unionArrays[1][i].getUConst());
                        break;
                    default:
                        UNREACHABLE();
                        break;
                }
            }
            break;
        }

        case EOpGreaterThanComponentWise:
        {
            resultArray = new TConstantUnion[maxObjectSize];
            for (size_t i = 0; i < maxObjectSize; i++)
            {
                switch (basicType)
                {
                    case EbtFloat:
                        resultArray[i].setBConst(unionArrays[0][i].getFConst() >
                                                 unionArrays[1][i].getFConst());
                        break;
                    case EbtInt:
                        resultArray[i].setBConst(unionArrays[0][i].getIConst() >
                                                 unionArrays[1][i].getIConst());
                        break;
                    case EbtUInt:
                        resultArray[i].setBConst(unionArrays[0][i].getUConst() >
                                                 unionArrays[1][i].getUConst());
                        break;
                    default:
                        UNREACHABLE();
                        break;
                }
            }
            break;
        }
        case EOpGreaterThanEqualComponentWise:
        {
            resultArray = new TConstantUnion[maxObjectSize];
            for (size_t i = 0; i < maxObjectSize; i++)
            {
                switch (basicType)
                {
                    case EbtFloat:
                        resultArray[i].setBConst(unionArrays[0][i].getFConst() >=
                                                 unionArrays[1][i].getFConst());
                        break;
                    case EbtInt:
                        resultArray[i].setBConst(unionArrays[0][i].getIConst() >=
                                                 unionArrays[1][i].getIConst());
                        break;
                    case EbtUInt:
                        resultArray[i].setBConst(unionArrays[0][i].getUConst() >=
                                                 unionArrays[1][i].getUConst());
                        break;
                    default:
                        UNREACHABLE();
                        break;
                }
            }
        }
        break;

        case EOpEqualComponentWise:
        {
            resultArray = new TConstantUnion[maxObjectSize];
            for (size_t i = 0; i < maxObjectSize; i++)
            {
                switch (basicType)
                {
                    case EbtFloat:
                        resultArray[i].setBConst(unionArrays[0][i].getFConst() ==
                                                 unionArrays[1][i].getFConst());
                        break;
                    case EbtInt:
                        resultArray[i].setBConst(unionArrays[0][i].getIConst() ==
                                                 unionArrays[1][i].getIConst());
                        break;
                    case EbtUInt:
                        resultArray[i].setBConst(unionArrays[0][i].getUConst() ==
                                                 unionArrays[1][i].getUConst());
                        break;
                    case EbtBool:
                        resultArray[i].setBConst(unionArrays[0][i].getBConst() ==
                                                 unionArrays[1][i].getBConst());
                        break;
                    default:
                        UNREACHABLE();
                        break;
                }
            }
            break;
        }

        case EOpNotEqualComponentWise:
        {
            resultArray = new TConstantUnion[maxObjectSize];
            for (size_t i = 0; i < maxObjectSize; i++)
            {
                switch (basicType)
                {
                    case EbtFloat:
                        resultArray[i].setBConst(unionArrays[0][i].getFConst() !=
                                                 unionArrays[1][i].getFConst());
                        break;
                    case EbtInt:
                        resultArray[i].setBConst(unionArrays[0][i].getIConst() !=
                                                 unionArrays[1][i].getIConst());
                        break;
                    case EbtUInt:
                        resultArray[i].setBConst(unionArrays[0][i].getUConst() !=
                                                 unionArrays[1][i].getUConst());
                        break;
                    case EbtBool:
                        resultArray[i].setBConst(unionArrays[0][i].getBConst() !=
                                                 unionArrays[1][i].getBConst());
                        break;
                    default:
                        UNREACHABLE();
                        break;
                }
            }
            break;
        }

        case EOpDistance:
        {
            ASSERT(basicType == EbtFloat);
            TConstantUnion *distanceArray = new TConstantUnion[maxObjectSize];
            resultArray                   = new TConstantUnion();
            for (size_t i = 0; i < maxObjectSize; i++)
            {
                float x = unionArrays[0][i].getFConst();
                float y = unionArrays[1][i].getFConst();
                distanceArray[i].setFConst(x - y);
            }
            resultArray->setFConst(VectorLength(distanceArray, maxObjectSize));
            break;
        }

        case EOpDot:
            ASSERT(basicType == EbtFloat);
            resultArray = new TConstantUnion();
            resultArray->setFConst(VectorDotProduct(unionArrays[0], unionArrays[1], maxObjectSize));
            break;

        case EOpCross:
        {
            ASSERT(basicType == EbtFloat && maxObjectSize == 3);
            resultArray = new TConstantUnion[maxObjectSize];
            float x0    = unionArrays[0][0].getFConst();
            float x1    = unionArrays[0][1].getFConst();
            float x2    = unionArrays[0][2].getFConst();
            float y0    = unionArrays[1][0].getFConst();
            float y1    = unionArrays[1][1].getFConst();
            float y2    = unionArrays[1][2].getFConst();
            resultArray[0].setFConst(x1 * y2 - y1 * x2);
            resultArray[1].setFConst(x2 * y0 - y2 * x0);
            resultArray[2].setFConst(x0 * y1 - y0 * x1);
            break;
        }

        case EOpReflect:
        {
            ASSERT(basicType == EbtFloat);
            // genType reflect (genType I, genType N) :
            //     For the incident vector I and surface orientation N, returns the reflection
            //     direction:
            //     I - 2 * dot(N, I) * N.
            resultArray      = new TConstantUnion[maxObjectSize];
            float dotProduct = VectorDotProduct(unionArrays[1], unionArrays[0], maxObjectSize);
            for (size_t i = 0; i < maxObjectSize; i++)
            {
                float result = unionArrays[0][i].getFConst() -
                               2.0f * dotProduct * unionArrays[1][i].getFConst();
                resultArray[i].setFConst(result);
            }
            break;
        }

        case EOpMulMatrixComponentWise:
        {
            ASSERT(basicType == EbtFloat && (*arguments)[0]->getAsTyped()->isMatrix() &&
                   (*arguments)[1]->getAsTyped()->isMatrix());
            // Perform component-wise matrix multiplication.
            resultArray = new TConstantUnion[maxObjectSize];
            int size    = (*arguments)[0]->getAsTyped()->getNominalSize();
            angle::Matrix<float> result =
                GetMatrix(unionArrays[0], size).compMult(GetMatrix(unionArrays[1], size));
            SetUnionArrayFromMatrix(result, resultArray);
            break;
        }

        case EOpOuterProduct:
        {
            ASSERT(basicType == EbtFloat);
            size_t numRows = (*arguments)[0]->getAsTyped()->getType().getObjectSize();
            size_t numCols = (*arguments)[1]->getAsTyped()->getType().getObjectSize();
            resultArray    = new TConstantUnion[numRows * numCols];
            angle::Matrix<float> result =
                GetMatrix(unionArrays[0], static_cast<int>(numRows), 1)
                    .outerProduct(GetMatrix(unionArrays[1], 1, static_cast<int>(numCols)));
            SetUnionArrayFromMatrix(result, resultArray);
            break;
        }

        case EOpClamp:
        {
            resultArray = new TConstantUnion[maxObjectSize];
            for (size_t i = 0; i < maxObjectSize; i++)
            {
                switch (basicType)
                {
                    case EbtFloat:
                    {
                        float x   = unionArrays[0][i].getFConst();
                        float min = unionArrays[1][i].getFConst();
                        float max = unionArrays[2][i].getFConst();
                        // Results are undefined if min > max.
                        if (min > max)
                            UndefinedConstantFoldingError(loc, op, basicType, diagnostics,
                                                          &resultArray[i]);
                        else
                            resultArray[i].setFConst(gl::clamp(x, min, max));
                        break;
                    }

                    case EbtInt:
                    {
                        int x   = unionArrays[0][i].getIConst();
                        int min = unionArrays[1][i].getIConst();
                        int max = unionArrays[2][i].getIConst();
                        // Results are undefined if min > max.
                        if (min > max)
                            UndefinedConstantFoldingError(loc, op, basicType, diagnostics,
                                                          &resultArray[i]);
                        else
                            resultArray[i].setIConst(gl::clamp(x, min, max));
                        break;
                    }
                    case EbtUInt:
                    {
                        unsigned int x   = unionArrays[0][i].getUConst();
                        unsigned int min = unionArrays[1][i].getUConst();
                        unsigned int max = unionArrays[2][i].getUConst();
                        // Results are undefined if min > max.
                        if (min > max)
                            UndefinedConstantFoldingError(loc, op, basicType, diagnostics,
                                                          &resultArray[i]);
                        else
                            resultArray[i].setUConst(gl::clamp(x, min, max));
                        break;
                    }
                    default:
                        UNREACHABLE();
                        break;
                }
            }
            break;
        }

        case EOpMix:
        {
            ASSERT(basicType == EbtFloat);
            resultArray = new TConstantUnion[maxObjectSize];
            for (size_t i = 0; i < maxObjectSize; i++)
            {
                float x         = unionArrays[0][i].getFConst();
                float y         = unionArrays[1][i].getFConst();
                TBasicType type = (*arguments)[2]->getAsTyped()->getType().getBasicType();
                if (type == EbtFloat)
                {
                    // Returns the linear blend of x and y, i.e., x * (1 - a) + y * a.
                    float a = unionArrays[2][i].getFConst();
                    resultArray[i].setFConst(x * (1.0f - a) + y * a);
                }
                else  // 3rd parameter is EbtBool
                {
                    ASSERT(type == EbtBool);
                    // Selects which vector each returned component comes from.
                    // For a component of a that is false, the corresponding component of x is
                    // returned.
                    // For a component of a that is true, the corresponding component of y is
                    // returned.
                    bool a = unionArrays[2][i].getBConst();
                    resultArray[i].setFConst(a ? y : x);
                }
            }
            break;
        }

        case EOpSmoothStep:
        {
            ASSERT(basicType == EbtFloat);
            resultArray = new TConstantUnion[maxObjectSize];
            for (size_t i = 0; i < maxObjectSize; i++)
            {
                float edge0 = unionArrays[0][i].getFConst();
                float edge1 = unionArrays[1][i].getFConst();
                float x     = unionArrays[2][i].getFConst();
                // Results are undefined if edge0 >= edge1.
                if (edge0 >= edge1)
                {
                    UndefinedConstantFoldingError(loc, op, basicType, diagnostics, &resultArray[i]);
                }
                else
                {
                    // Returns 0.0 if x <= edge0 and 1.0 if x >= edge1 and performs smooth
                    // Hermite interpolation between 0 and 1 when edge0 < x < edge1.
                    float t = gl::clamp((x - edge0) / (edge1 - edge0), 0.0f, 1.0f);
                    resultArray[i].setFConst(t * t * (3.0f - 2.0f * t));
                }
            }
            break;
        }

        case EOpLdexp:
        {
            resultArray = new TConstantUnion[maxObjectSize];
            for (size_t i = 0; i < maxObjectSize; i++)
            {
                float x = unionArrays[0][i].getFConst();
                int exp = unionArrays[1][i].getIConst();
                if (exp > 128)
                {
                    UndefinedConstantFoldingError(loc, op, basicType, diagnostics, &resultArray[i]);
                }
                else
                {
                    resultArray[i].setFConst(gl::Ldexp(x, exp));
                }
            }
            break;
        }

        case EOpFaceforward:
        {
            ASSERT(basicType == EbtFloat);
            // genType faceforward(genType N, genType I, genType Nref) :
            //     If dot(Nref, I) < 0 return N, otherwise return -N.
            resultArray      = new TConstantUnion[maxObjectSize];
            float dotProduct = VectorDotProduct(unionArrays[2], unionArrays[1], maxObjectSize);
            for (size_t i = 0; i < maxObjectSize; i++)
            {
                if (dotProduct < 0)
                    resultArray[i].setFConst(unionArrays[0][i].getFConst());
                else
                    resultArray[i].setFConst(-unionArrays[0][i].getFConst());
            }
            break;
        }

        case EOpRefract:
        {
            ASSERT(basicType == EbtFloat);
            // genType refract(genType I, genType N, float eta) :
            //     For the incident vector I and surface normal N, and the ratio of indices of
            //     refraction eta,
            //     return the refraction vector. The result is computed by
            //         k = 1.0 - eta * eta * (1.0 - dot(N, I) * dot(N, I))
            //         if (k < 0.0)
            //             return genType(0.0)
            //         else
            //             return eta * I - (eta * dot(N, I) + sqrt(k)) * N
            resultArray      = new TConstantUnion[maxObjectSize];
            float dotProduct = VectorDotProduct(unionArrays[1], unionArrays[0], maxObjectSize);
            for (size_t i = 0; i < maxObjectSize; i++)
            {
                float eta = unionArrays[2][i].getFConst();
                float k   = 1.0f - eta * eta * (1.0f - dotProduct * dotProduct);
                if (k < 0.0f)
                    resultArray[i].setFConst(0.0f);
                else
                    resultArray[i].setFConst(eta * unionArrays[0][i].getFConst() -
                                             (eta * dotProduct + sqrtf(k)) *
                                                 unionArrays[1][i].getFConst());
            }
            break;
        }
        case EOpBitfieldExtract:
        {
            resultArray = new TConstantUnion[maxObjectSize];
            for (size_t i = 0; i < maxObjectSize; ++i)
            {
                int offset = unionArrays[1][0].getIConst();
                int bits   = unionArrays[2][0].getIConst();
                if (bits == 0)
                {
                    if (aggregate->getBasicType() == EbtInt)
                    {
                        resultArray[i].setIConst(0);
                    }
                    else
                    {
                        ASSERT(aggregate->getBasicType() == EbtUInt);
                        resultArray[i].setUConst(0);
                    }
                }
                else if (offset < 0 || bits < 0 || offset >= 32 || bits > 32 || offset + bits > 32)
                {
                    UndefinedConstantFoldingError(loc, op, aggregate->getBasicType(), diagnostics,
                                                  &resultArray[i]);
                }
                else
                {
                    // bits can be 32 here, so we need to avoid bit shift overflow.
                    uint32_t maskMsb = 1u << (bits - 1);
                    uint32_t mask    = ((maskMsb - 1u) | maskMsb) << offset;
                    if (aggregate->getBasicType() == EbtInt)
                    {
                        uint32_t value = static_cast<uint32_t>(unionArrays[0][i].getIConst());
                        uint32_t resultUnsigned = (value & mask) >> offset;
                        if ((resultUnsigned & maskMsb) != 0)
                        {
                            // The most significant bits (from bits+1 to the most significant bit)
                            // should be set to 1.
                            uint32_t higherBitsMask = ((1u << (32 - bits)) - 1u) << bits;
                            resultUnsigned |= higherBitsMask;
                        }
                        resultArray[i].setIConst(static_cast<int32_t>(resultUnsigned));
                    }
                    else
                    {
                        ASSERT(aggregate->getBasicType() == EbtUInt);
                        uint32_t value = unionArrays[0][i].getUConst();
                        resultArray[i].setUConst((value & mask) >> offset);
                    }
                }
            }
            break;
        }
        case EOpBitfieldInsert:
        {
            resultArray = new TConstantUnion[maxObjectSize];
            for (size_t i = 0; i < maxObjectSize; ++i)
            {
                int offset = unionArrays[2][0].getIConst();
                int bits   = unionArrays[3][0].getIConst();
                if (bits == 0)
                {
                    if (aggregate->getBasicType() == EbtInt)
                    {
                        int32_t base = unionArrays[0][i].getIConst();
                        resultArray[i].setIConst(base);
                    }
                    else
                    {
                        ASSERT(aggregate->getBasicType() == EbtUInt);
                        uint32_t base = unionArrays[0][i].getUConst();
                        resultArray[i].setUConst(base);
                    }
                }
                else if (offset < 0 || bits < 0 || offset >= 32 || bits > 32 || offset + bits > 32)
                {
                    UndefinedConstantFoldingError(loc, op, aggregate->getBasicType(), diagnostics,
                                                  &resultArray[i]);
                }
                else
                {
                    // bits can be 32 here, so we need to avoid bit shift overflow.
                    uint32_t maskMsb    = 1u << (bits - 1);
                    uint32_t insertMask = ((maskMsb - 1u) | maskMsb) << offset;
                    uint32_t baseMask   = ~insertMask;
                    if (aggregate->getBasicType() == EbtInt)
                    {
                        uint32_t base   = static_cast<uint32_t>(unionArrays[0][i].getIConst());
                        uint32_t insert = static_cast<uint32_t>(unionArrays[1][i].getIConst());
                        uint32_t resultUnsigned =
                            (base & baseMask) | ((insert << offset) & insertMask);
                        resultArray[i].setIConst(static_cast<int32_t>(resultUnsigned));
                    }
                    else
                    {
                        ASSERT(aggregate->getBasicType() == EbtUInt);
                        uint32_t base   = unionArrays[0][i].getUConst();
                        uint32_t insert = unionArrays[1][i].getUConst();
                        resultArray[i].setUConst((base & baseMask) |
                                                 ((insert << offset) & insertMask));
                    }
                }
            }
            break;
        }

        default:
            UNREACHABLE();
            return nullptr;
    }
    return resultArray;
}

}  // namespace sh
kc3-lang/angle/src/compiler/translator/IntermNode.cpp

Commit

kc3-lang/angle /src/compiler/translator/IntermNode.cpp
