Source/ThirdParty/ANGLE/src/compiler/OutputGLSL.cpp - platform/external/webkit - Git at Google

 //
 // Copyright (c) 2002-2010 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.
 //

 #include "compiler/OutputGLSL.h"
 #include "compiler/debug.h"

 namespace
 {
 TString getTypeName(const TType& type)
 {
     TInfoSinkBase out;
     if (type.isMatrix())
     {
         out << "mat";
         out << type.getNominalSize();
     }
     else if (type.isVector())
     {
         switch (type.getBasicType())
         {
             case EbtFloat: out << "vec"; break;
             case EbtInt: out << "ivec"; break;
             case EbtBool: out << "bvec"; break;
             default: UNREACHABLE(); break;
         }
         out << type.getNominalSize();
     }
     else
     {
         if (type.getBasicType() == EbtStruct)
             out << type.getTypeName();
         else
             out << type.getBasicString();
     }
     return TString(out.c_str());
 }

 TString arrayBrackets(const TType& type)
 {
     ASSERT(type.isArray());
     TInfoSinkBase out;
     out << "[" << type.getArraySize() << "]";
     return TString(out.c_str());
 }

 bool isSingleStatement(TIntermNode* node) {
     if (const TIntermAggregate* aggregate = node->getAsAggregate())
     {
         return (aggregate->getOp() != EOpFunction) &&
                (aggregate->getOp() != EOpSequence);
     }
     else if (const TIntermSelection* selection = node->getAsSelectionNode())
     {
         // Ternary operators are usually part of an assignment operator.
         // This handles those rare cases in which they are all by themselves.
         return selection->usesTernaryOperator();
     }
     else if (node->getAsLoopNode())
     {
         return false;
     }
     return true;
 }
 }  // namespace

 TOutputGLSL::TOutputGLSL(TInfoSinkBase& objSink)
     : TIntermTraverser(true, true, true),
       mObjSink(objSink),
       mDeclaringVariables(false)
 {
 }

 void TOutputGLSL::writeTriplet(Visit visit, const char* preStr, const char* inStr, const char* postStr)
 {
     TInfoSinkBase& out = objSink();
     if (visit == PreVisit && preStr)
     {
         out << preStr;
     }
     else if (visit == InVisit && inStr)
     {
         out << inStr;
     }
     else if (visit == PostVisit && postStr)
     {
         out << postStr;
     }
 }

 void TOutputGLSL::writeVariableType(const TType& type)
 {
     TInfoSinkBase& out = objSink();
     TQualifier qualifier = type.getQualifier();
     // TODO(alokp): Validate qualifier for variable declarations.
     if ((qualifier != EvqTemporary) && (qualifier != EvqGlobal))
         out << type.getQualifierString() << " ";

     // Declare the struct if we have not done so already.
     if ((type.getBasicType() == EbtStruct) &&
         (mDeclaredStructs.find(type.getTypeName()) == mDeclaredStructs.end()))
     {
         out << "struct " << type.getTypeName() << "{\n";
         const TTypeList* structure = type.getStruct();
         ASSERT(structure != NULL);
         for (size_t i = 0; i < structure->size(); ++i)
         {
             const TType* fieldType = (*structure)[i].type;
             ASSERT(fieldType != NULL);
             out << getTypeName(*fieldType) << " " << fieldType->getFieldName();
             if (fieldType->isArray())
                 out << arrayBrackets(*fieldType);
             out << ";\n";
         }
         out << "}";
         mDeclaredStructs.insert(type.getTypeName());
     }
     else
     {
         out << getTypeName(type);
     }
 }

 void TOutputGLSL::writeFunctionParameters(const TIntermSequence& args)
 {
     TInfoSinkBase& out = objSink();
     for (TIntermSequence::const_iterator iter = args.begin();
          iter != args.end(); ++iter)
     {
         const TIntermSymbol* arg = (*iter)->getAsSymbolNode();
         ASSERT(arg != NULL);

         const TType& type = arg->getType();
         TQualifier qualifier = type.getQualifier();
         // TODO(alokp): Validate qualifier for function arguments.
         if ((qualifier != EvqTemporary) && (qualifier != EvqGlobal))
             out << type.getQualifierString() << " ";

         out << getTypeName(type);

         const TString& name = arg->getSymbol();
         if (!name.empty())
             out << " " << name;
         if (type.isArray())
             out << arrayBrackets(type);

         // Put a comma if this is not the last argument.
         if (iter != args.end() - 1)
             out << ", ";
     }
 }

 const ConstantUnion* TOutputGLSL::writeConstantUnion(const TType& type,
                                                      const ConstantUnion* pConstUnion)
 {
     TInfoSinkBase& out = objSink();

     if (type.getBasicType() == EbtStruct)
     {
         out << type.getTypeName() << "(";
         const TTypeList* structure = type.getStruct();
         ASSERT(structure != NULL);
         for (size_t i = 0; i < structure->size(); ++i)
         {
             const TType* fieldType = (*structure)[i].type;
             ASSERT(fieldType != NULL);
             pConstUnion = writeConstantUnion(*fieldType, pConstUnion);
             if (i != structure->size() - 1) out << ", ";
         }
         out << ")";
     }
     else
     {
         int size = type.getObjectSize();
         bool writeType = size > 1;
         if (writeType) out << getTypeName(type) << "(";
         for (int i = 0; i < size; ++i, ++pConstUnion)
         {
             switch (pConstUnion->getType())
             {
                 case EbtFloat: out << pConstUnion->getFConst(); break;
                 case EbtInt: out << pConstUnion->getIConst(); break;
                 case EbtBool: out << pConstUnion->getBConst(); break;
                 default: UNREACHABLE();
             }
             if (i != size - 1) out << ", ";
         }
         if (writeType) out << ")";
     }
     return pConstUnion;
 }

 void TOutputGLSL::visitSymbol(TIntermSymbol* node)
 {
     TInfoSinkBase& out = objSink();
     out << node->getSymbol();

     if (mDeclaringVariables && node->getType().isArray())
         out << arrayBrackets(node->getType());
 }

 void TOutputGLSL::visitConstantUnion(TIntermConstantUnion* node)
 {
     writeConstantUnion(node->getType(), node->getUnionArrayPointer());
 }

 bool TOutputGLSL::visitBinary(Visit visit, TIntermBinary* node)
 {
     bool visitChildren = true;
     TInfoSinkBase& out = objSink();
     switch (node->getOp())
     {
         case EOpInitialize:
             if (visit == InVisit)
             {
                 out << " = ";
                 // RHS of initialize is not being declared.
                 mDeclaringVariables = false;
             }
             break;
         case EOpAssign: writeTriplet(visit, "(", " = ", ")"); break;
         case EOpAddAssign: writeTriplet(visit, "(", " += ", ")"); break;
         case EOpSubAssign: writeTriplet(visit, "(", " -= ", ")"); break;
         case EOpDivAssign: writeTriplet(visit, "(", " /= ", ")"); break;
         // Notice the fall-through.
         case EOpMulAssign:
         case EOpVectorTimesMatrixAssign:
         case EOpVectorTimesScalarAssign:
         case EOpMatrixTimesScalarAssign:
         case EOpMatrixTimesMatrixAssign:
             writeTriplet(visit, "(", " *= ", ")");
             break;

         case EOpIndexDirect:
         case EOpIndexIndirect:
             writeTriplet(visit, NULL, "[", "]");
             break;
         case EOpIndexDirectStruct:
             if (visit == InVisit)
             {
                 out << ".";
                 // TODO(alokp): ASSERT
                 out << node->getType().getFieldName();
                 visitChildren = false;
             }
             break;
         case EOpVectorSwizzle:
             if (visit == InVisit)
             {
                 out << ".";
                 TIntermAggregate* rightChild = node->getRight()->getAsAggregate();
                 TIntermSequence& sequence = rightChild->getSequence();
                 for (TIntermSequence::iterator sit = sequence.begin(); sit != sequence.end(); ++sit)
                 {
                     TIntermConstantUnion* element = (*sit)->getAsConstantUnion();
                     ASSERT(element->getBasicType() == EbtInt);
                     ASSERT(element->getNominalSize() == 1);
                     const ConstantUnion& data = element->getUnionArrayPointer()[0];
                     ASSERT(data.getType() == EbtInt);
                     switch (data.getIConst())
                     {
                         case 0: out << "x"; break;
                         case 1: out << "y"; break;
                         case 2: out << "z"; break;
                         case 3: out << "w"; break;
                         default: UNREACHABLE(); break;
                     }
                 }
                 visitChildren = false;
             }
             break;

         case EOpAdd: writeTriplet(visit, "(", " + ", ")"); break;
         case EOpSub: writeTriplet(visit, "(", " - ", ")"); break;
         case EOpMul: writeTriplet(visit, "(", " * ", ")"); break;
         case EOpDiv: writeTriplet(visit, "(", " / ", ")"); break;
         case EOpMod: UNIMPLEMENTED(); break;
         case EOpEqual: writeTriplet(visit, "(", " == ", ")"); break;
         case EOpNotEqual: writeTriplet(visit, "(", " != ", ")"); break;
         case EOpLessThan: writeTriplet(visit, "(", " < ", ")"); break;
         case EOpGreaterThan: writeTriplet(visit, "(", " > ", ")"); break;
         case EOpLessThanEqual: writeTriplet(visit, "(", " <= ", ")"); break;
         case EOpGreaterThanEqual: writeTriplet(visit, "(", " >= ", ")"); break;

         // Notice the fall-through.
         case EOpVectorTimesScalar:
         case EOpVectorTimesMatrix:
         case EOpMatrixTimesVector:
         case EOpMatrixTimesScalar:
         case EOpMatrixTimesMatrix:
             writeTriplet(visit, "(", " * ", ")");
             break;

         case EOpLogicalOr: writeTriplet(visit, "(", " || ", ")"); break;
         case EOpLogicalXor: writeTriplet(visit, "(", " ^^ ", ")"); break;
         case EOpLogicalAnd: writeTriplet(visit, "(", " && ", ")"); break;
         default: UNREACHABLE(); break;
     }

     return visitChildren;
 }

 bool TOutputGLSL::visitUnary(Visit visit, TIntermUnary* node)
 {
     switch (node->getOp())
     {
         case EOpNegative: writeTriplet(visit, "(-", NULL, ")"); break;
         case EOpVectorLogicalNot: writeTriplet(visit, "not(", NULL, ")"); break;
         case EOpLogicalNot: writeTriplet(visit, "(!", NULL, ")"); break;

         case EOpPostIncrement: writeTriplet(visit, "(", NULL, "++)"); break;
         case EOpPostDecrement: writeTriplet(visit, "(", NULL, "--)"); break;
         case EOpPreIncrement: writeTriplet(visit, "(++", NULL, ")"); break;
         case EOpPreDecrement: writeTriplet(visit, "(--", NULL, ")"); break;

         case EOpConvIntToBool:
         case EOpConvFloatToBool:
             switch (node->getOperand()->getType().getNominalSize())
             {
                 case 1: writeTriplet(visit, "bool(", NULL, ")");  break;
                 case 2: writeTriplet(visit, "bvec2(", NULL, ")"); break;
                 case 3: writeTriplet(visit, "bvec3(", NULL, ")"); break;
                 case 4: writeTriplet(visit, "bvec4(", NULL, ")"); break;
                 default: UNREACHABLE();
             }
             break;
         case EOpConvBoolToFloat:
         case EOpConvIntToFloat:
             switch (node->getOperand()->getType().getNominalSize())
             {
                 case 1: writeTriplet(visit, "float(", NULL, ")");  break;
                 case 2: writeTriplet(visit, "vec2(", NULL, ")"); break;
                 case 3: writeTriplet(visit, "vec3(", NULL, ")"); break;
                 case 4: writeTriplet(visit, "vec4(", NULL, ")"); break;
                 default: UNREACHABLE();
             }
             break;
         case EOpConvFloatToInt:
         case EOpConvBoolToInt:
             switch (node->getOperand()->getType().getNominalSize())
             {
                 case 1: writeTriplet(visit, "int(", NULL, ")");  break;
                 case 2: writeTriplet(visit, "ivec2(", NULL, ")"); break;
                 case 3: writeTriplet(visit, "ivec3(", NULL, ")"); break;
                 case 4: writeTriplet(visit, "ivec4(", NULL, ")"); break;
                 default: UNREACHABLE();
             }
             break;

         case EOpRadians: writeTriplet(visit, "radians(", NULL, ")"); break;
         case EOpDegrees: writeTriplet(visit, "degrees(", NULL, ")"); break;
         case EOpSin: writeTriplet(visit, "sin(", NULL, ")"); break;
         case EOpCos: writeTriplet(visit, "cos(", NULL, ")"); break;
         case EOpTan: writeTriplet(visit, "tan(", NULL, ")"); break;
         case EOpAsin: writeTriplet(visit, "asin(", NULL, ")"); break;
         case EOpAcos: writeTriplet(visit, "acos(", NULL, ")"); break;
         case EOpAtan: writeTriplet(visit, "atan(", NULL, ")"); break;

         case EOpExp: writeTriplet(visit, "exp(", NULL, ")"); break;
         case EOpLog: writeTriplet(visit, "log(", NULL, ")"); break;
         case EOpExp2: writeTriplet(visit, "exp2(", NULL, ")"); break;
         case EOpLog2: writeTriplet(visit, "log2(", NULL, ")"); break;
         case EOpSqrt: writeTriplet(visit, "sqrt(", NULL, ")"); break;
         case EOpInverseSqrt: writeTriplet(visit, "inversesqrt(", NULL, ")"); break;

         case EOpAbs: writeTriplet(visit, "abs(", NULL, ")"); break;
         case EOpSign: writeTriplet(visit, "sign(", NULL, ")"); break;
         case EOpFloor: writeTriplet(visit, "floor(", NULL, ")"); break;
         case EOpCeil: writeTriplet(visit, "ceil(", NULL, ")"); break;
         case EOpFract: writeTriplet(visit, "fract(", NULL, ")"); break;

         case EOpLength: writeTriplet(visit, "length(", NULL, ")"); break;
         case EOpNormalize: writeTriplet(visit, "normalize(", NULL, ")"); break;

         case EOpDFdx: writeTriplet(visit, "dFdx(", NULL, ")"); break;
         case EOpDFdy: writeTriplet(visit, "dFdy(", NULL, ")"); break;
         case EOpFwidth: writeTriplet(visit, "fwidth(", NULL, ")"); break;

         case EOpAny: writeTriplet(visit, "any(", NULL, ")"); break;
         case EOpAll: writeTriplet(visit, "all(", NULL, ")"); break;

         default: UNREACHABLE(); break;
     }

     return true;
 }

 bool TOutputGLSL::visitSelection(Visit visit, TIntermSelection* node)
 {
     TInfoSinkBase& out = objSink();

     if (node->usesTernaryOperator())
     {
         // Notice two brackets at the beginning and end. The outer ones
         // encapsulate the whole ternary expression. This preserves the
         // order of precedence when ternary expressions are used in a
         // compound expression, i.e., c = 2 * (a < b ? 1 : 2).
         out << "((";
         node->getCondition()->traverse(this);
         out << ") ? (";
         node->getTrueBlock()->traverse(this);
         out << ") : (";
         node->getFalseBlock()->traverse(this);
         out << "))";
     }
     else
     {
         out << "if (";
         node->getCondition()->traverse(this);
         out << ")\n";

         incrementDepth();
         visitCodeBlock(node->getTrueBlock());

         if (node->getFalseBlock())
         {
             out << "else\n";
             visitCodeBlock(node->getFalseBlock());
         }
         decrementDepth();
     }
     return false;
 }

 bool TOutputGLSL::visitAggregate(Visit visit, TIntermAggregate* node)
 {
     bool visitChildren = true;
     TInfoSinkBase& out = objSink();
     switch (node->getOp())
     {
         case EOpSequence: {
             // Scope the sequences except when at the global scope.
             if (depth > 0) out << "{\n";

             incrementDepth();
             const TIntermSequence& sequence = node->getSequence();
             for (TIntermSequence::const_iterator iter = sequence.begin();
                  iter != sequence.end(); ++iter)
             {
                 TIntermNode* node = *iter;
                 ASSERT(node != NULL);
                 node->traverse(this);

                 if (isSingleStatement(node))
                     out << ";\n";
             }
             decrementDepth();

             // Scope the sequences except when at the global scope.
             if (depth > 0) out << "}\n";
             visitChildren = false;
             break;
         }
         case EOpPrototype: {
             // Function declaration.
             ASSERT(visit == PreVisit);
             TString returnType = getTypeName(node->getType());
             out << returnType << " " << node->getName();

             out << "(";
             writeFunctionParameters(node->getSequence());
             out << ")";

             visitChildren = false;
             break;
         }
         case EOpFunction: {
             // Function definition.
             ASSERT(visit == PreVisit);
             TString returnType = getTypeName(node->getType());
             TString functionName = TFunction::unmangleName(node->getName());
             out << returnType << " " << functionName;

             incrementDepth();
             // Function definition node contains one or two children nodes
             // representing function parameters and function body. The latter
             // is not present in case of empty function bodies.
             const TIntermSequence& sequence = node->getSequence();
             ASSERT((sequence.size() == 1) || (sequence.size() == 2));
             TIntermSequence::const_iterator seqIter = sequence.begin();

             // Traverse function parameters.
             TIntermAggregate* params = (*seqIter)->getAsAggregate();
             ASSERT(params != NULL);
             ASSERT(params->getOp() == EOpParameters);
             params->traverse(this);

             // Traverse function body.
             TIntermAggregate* body = ++seqIter != sequence.end() ?
                 (*seqIter)->getAsAggregate() : NULL;
             visitCodeBlock(body);
             decrementDepth();

             // Fully processed; no need to visit children.
             visitChildren = false;
             break;
         }
         case EOpFunctionCall:
             // Function call.
             if (visit == PreVisit)
             {
                 TString functionName = TFunction::unmangleName(node->getName());
                 out << functionName << "(";
             }
             else if (visit == InVisit)
             {
                 out << ", ";
             }
             else
             {
                 out << ")";
             }
             break;
         case EOpParameters: {
             // Function parameters.
             ASSERT(visit == PreVisit);
             out << "(";
             writeFunctionParameters(node->getSequence());
             out << ")";
             visitChildren = false;
             break;
         }
         case EOpDeclaration: {
             // Variable declaration.
             if (visit == PreVisit)
             {
                 const TIntermSequence& sequence = node->getSequence();
                 const TIntermTyped* variable = sequence.front()->getAsTyped();
                 writeVariableType(variable->getType());
                 out << " ";
                 mDeclaringVariables = true;
             }
             else if (visit == InVisit)
             {
                 out << ", ";
                 mDeclaringVariables = true;
             }
             else
             {
                 mDeclaringVariables = false;
             }
             break;
         }
         case EOpConstructFloat: writeTriplet(visit, "float(", NULL, ")"); break;
         case EOpConstructVec2: writeTriplet(visit, "vec2(", ", ", ")"); break;
         case EOpConstructVec3: writeTriplet(visit, "vec3(", ", ", ")"); break;
         case EOpConstructVec4: writeTriplet(visit, "vec4(", ", ", ")"); break;
         case EOpConstructBool: writeTriplet(visit, "bool(", NULL, ")"); break;
         case EOpConstructBVec2: writeTriplet(visit, "bvec2(", ", ", ")"); break;
         case EOpConstructBVec3: writeTriplet(visit, "bvec3(", ", ", ")"); break;
         case EOpConstructBVec4: writeTriplet(visit, "bvec4(", ", ", ")"); break;
         case EOpConstructInt: writeTriplet(visit, "int(", NULL, ")"); break;
         case EOpConstructIVec2: writeTriplet(visit, "ivec2(", ", ", ")"); break;
         case EOpConstructIVec3: writeTriplet(visit, "ivec3(", ", ", ")"); break;
         case EOpConstructIVec4: writeTriplet(visit, "ivec4(", ", ", ")"); break;
         case EOpConstructMat2: writeTriplet(visit, "mat2(", ", ", ")"); break;
         case EOpConstructMat3: writeTriplet(visit, "mat3(", ", ", ")"); break;
         case EOpConstructMat4: writeTriplet(visit, "mat4(", ", ", ")"); break;
         case EOpConstructStruct:
             if (visit == PreVisit)
             {
                 const TType& type = node->getType();
                 ASSERT(type.getBasicType() == EbtStruct);
                 out << type.getTypeName() << "(";
             }
             else if (visit == InVisit)
             {
                 out << ", ";
             }
             else
             {
                 out << ")";
             }
             break;

         case EOpLessThan: writeTriplet(visit, "lessThan(", ", ", ")"); break;
         case EOpGreaterThan: writeTriplet(visit, "greaterThan(", ", ", ")"); break;
         case EOpLessThanEqual: writeTriplet(visit, "lessThanEqual(", ", ", ")"); break;
         case EOpGreaterThanEqual: writeTriplet(visit, "greaterThanEqual(", ", ", ")"); break;
         case EOpVectorEqual: writeTriplet(visit, "equal(", ", ", ")"); break;
         case EOpVectorNotEqual: writeTriplet(visit, "notEqual(", ", ", ")"); break;
         case EOpComma: writeTriplet(visit, NULL, ", ", NULL); break;

         case EOpMod: writeTriplet(visit, "mod(", ", ", ")"); break;
         case EOpPow: writeTriplet(visit, "pow(", ", ", ")"); break;
         case EOpAtan: writeTriplet(visit, "atan(", ", ", ")"); break;
         case EOpMin: writeTriplet(visit, "min(", ", ", ")"); break;
         case EOpMax: writeTriplet(visit, "max(", ", ", ")"); break;
         case EOpClamp: writeTriplet(visit, "clamp(", ", ", ")"); break;
         case EOpMix: writeTriplet(visit, "mix(", ", ", ")"); break;
         case EOpStep: writeTriplet(visit, "step(", ", ", ")"); break;
         case EOpSmoothStep: writeTriplet(visit, "smoothstep(", ", ", ")"); break;

         case EOpDistance: writeTriplet(visit, "distance(", ", ", ")"); break;
         case EOpDot: writeTriplet(visit, "dot(", ", ", ")"); break;
         case EOpCross: writeTriplet(visit, "cross(", ", ", ")"); break;
         case EOpFaceForward: writeTriplet(visit, "faceforward(", ", ", ")"); break;
         case EOpReflect: writeTriplet(visit, "reflect(", ", ", ")"); break;
         case EOpRefract: writeTriplet(visit, "refract(", ", ", ")"); break;
         case EOpMul: writeTriplet(visit, "matrixCompMult(", ", ", ")"); break;

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

 bool TOutputGLSL::visitLoop(Visit visit, TIntermLoop* node)
 {
     TInfoSinkBase& out = objSink();

     incrementDepth();
     // Loop header.
     TLoopType loopType = node->getType();
     if (loopType == ELoopFor)  // for loop
     {
         out << "for (";
         if (node->getInit())
             node->getInit()->traverse(this);
         out << "; ";

         if (node->getCondition())
             node->getCondition()->traverse(this);
         out << "; ";

         if (node->getExpression())
             node->getExpression()->traverse(this);
         out << ")\n";
     }
     else if (loopType == ELoopWhile)  // while loop
     {
         out << "while (";
         ASSERT(node->getCondition() != NULL);
         node->getCondition()->traverse(this);
         out << ")\n";
     }
     else  // do-while loop
     {
         ASSERT(loopType == ELoopDoWhile);
         out << "do\n";
     }

     // Loop body.
     visitCodeBlock(node->getBody());

     // Loop footer.
     if (loopType == ELoopDoWhile)  // do-while loop
     {
         out << "while (";
         ASSERT(node->getCondition() != NULL);
         node->getCondition()->traverse(this);
         out << ");\n";
     }
     decrementDepth();

     // No need to visit children. They have been already processed in
     // this function.
     return false;
 }

 bool TOutputGLSL::visitBranch(Visit visit, TIntermBranch* node)
 {
     switch (node->getFlowOp())
     {
         case EOpKill: writeTriplet(visit, "discard", NULL, NULL); break;
         case EOpBreak: writeTriplet(visit, "break", NULL, NULL); break;
         case EOpContinue: writeTriplet(visit, "continue", NULL, NULL); break;
         case EOpReturn: writeTriplet(visit, "return ", NULL, NULL); break;
         default: UNREACHABLE(); break;
     }

     return true;
 }

 void TOutputGLSL::visitCodeBlock(TIntermNode* node) {
     TInfoSinkBase &out = objSink();
     if (node != NULL)
     {
         node->traverse(this);
         // Single statements not part of a sequence need to be terminated
         // with semi-colon.
         if (isSingleStatement(node))
             out << ";\n";
     }
     else
     {
         out << "{\n}\n";  // Empty code block.
     }
 }
	//
	// Copyright (c) 2002-2010 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.
	//

	#include "compiler/OutputGLSL.h"
	#include "compiler/debug.h"

	namespace
	{
	TString getTypeName(const TType& type)
	{
	TInfoSinkBase out;
	if (type.isMatrix())
	{
	out << "mat";
	out << type.getNominalSize();
	}
	else if (type.isVector())
	{
	switch (type.getBasicType())
	{
	case EbtFloat: out << "vec"; break;
	case EbtInt: out << "ivec"; break;
	case EbtBool: out << "bvec"; break;
	default: UNREACHABLE(); break;
	}
	out << type.getNominalSize();
	}
	else
	{
	if (type.getBasicType() == EbtStruct)
	out << type.getTypeName();
	else
	out << type.getBasicString();
	}
	return TString(out.c_str());
	}

	TString arrayBrackets(const TType& type)
	{
	ASSERT(type.isArray());
	TInfoSinkBase out;
	out << "[" << type.getArraySize() << "]";
	return TString(out.c_str());
	}

	bool isSingleStatement(TIntermNode* node) {
	if (const TIntermAggregate* aggregate = node->getAsAggregate())
	{
	return (aggregate->getOp() != EOpFunction) &&
	(aggregate->getOp() != EOpSequence);
	}
	else if (const TIntermSelection* selection = node->getAsSelectionNode())
	{
	// Ternary operators are usually part of an assignment operator.
	// This handles those rare cases in which they are all by themselves.
	return selection->usesTernaryOperator();
	}
	else if (node->getAsLoopNode())
	{
	return false;
	}
	return true;
	}
	} // namespace

	TOutputGLSL::TOutputGLSL(TInfoSinkBase& objSink)
	: TIntermTraverser(true, true, true),
	mObjSink(objSink),
	mDeclaringVariables(false)
	{
	}

	void TOutputGLSL::writeTriplet(Visit visit, const char* preStr, const char* inStr, const char* postStr)
	{
	TInfoSinkBase& out = objSink();
	if (visit == PreVisit && preStr)
	{
	out << preStr;
	}
	else if (visit == InVisit && inStr)
	{
	out << inStr;
	}
	else if (visit == PostVisit && postStr)
	{
	out << postStr;
	}
	}

	void TOutputGLSL::writeVariableType(const TType& type)
	{
	TInfoSinkBase& out = objSink();
	TQualifier qualifier = type.getQualifier();
	// TODO(alokp): Validate qualifier for variable declarations.
	if ((qualifier != EvqTemporary) && (qualifier != EvqGlobal))
	out << type.getQualifierString() << " ";

	// Declare the struct if we have not done so already.
	if ((type.getBasicType() == EbtStruct) &&
	(mDeclaredStructs.find(type.getTypeName()) == mDeclaredStructs.end()))
	{
	out << "struct " << type.getTypeName() << "{\n";
	const TTypeList* structure = type.getStruct();
	ASSERT(structure != NULL);
	for (size_t i = 0; i < structure->size(); ++i)
	{
	const TType* fieldType = (*structure)[i].type;
	ASSERT(fieldType != NULL);
	out << getTypeName(*fieldType) << " " << fieldType->getFieldName();
	if (fieldType->isArray())
	out << arrayBrackets(*fieldType);
	out << ";\n";
	}
	out << "}";
	mDeclaredStructs.insert(type.getTypeName());
	}
	else
	{
	out << getTypeName(type);
	}
	}

	void TOutputGLSL::writeFunctionParameters(const TIntermSequence& args)
	{
	TInfoSinkBase& out = objSink();
	for (TIntermSequence::const_iterator iter = args.begin();
	iter != args.end(); ++iter)
	{
	const TIntermSymbol* arg = (*iter)->getAsSymbolNode();
	ASSERT(arg != NULL);

	const TType& type = arg->getType();
	TQualifier qualifier = type.getQualifier();
	// TODO(alokp): Validate qualifier for function arguments.
	if ((qualifier != EvqTemporary) && (qualifier != EvqGlobal))
	out << type.getQualifierString() << " ";

	out << getTypeName(type);

	const TString& name = arg->getSymbol();
	if (!name.empty())
	out << " " << name;
	if (type.isArray())
	out << arrayBrackets(type);

	// Put a comma if this is not the last argument.
	if (iter != args.end() - 1)
	out << ", ";
	}
	}

	const ConstantUnion* TOutputGLSL::writeConstantUnion(const TType& type,
	const ConstantUnion* pConstUnion)
	{
	TInfoSinkBase& out = objSink();

	if (type.getBasicType() == EbtStruct)
	{
	out << type.getTypeName() << "(";
	const TTypeList* structure = type.getStruct();
	ASSERT(structure != NULL);
	for (size_t i = 0; i < structure->size(); ++i)
	{
	const TType* fieldType = (*structure)[i].type;
	ASSERT(fieldType != NULL);
	pConstUnion = writeConstantUnion(*fieldType, pConstUnion);
	if (i != structure->size() - 1) out << ", ";
	}
	out << ")";
	}
	else
	{
	int size = type.getObjectSize();
	bool writeType = size > 1;
	if (writeType) out << getTypeName(type) << "(";
	for (int i = 0; i < size; ++i, ++pConstUnion)
	{
	switch (pConstUnion->getType())
	{
	case EbtFloat: out << pConstUnion->getFConst(); break;
	case EbtInt: out << pConstUnion->getIConst(); break;
	case EbtBool: out << pConstUnion->getBConst(); break;
	default: UNREACHABLE();
	}
	if (i != size - 1) out << ", ";
	}
	if (writeType) out << ")";
	}
	return pConstUnion;
	}

	void TOutputGLSL::visitSymbol(TIntermSymbol* node)
	{
	TInfoSinkBase& out = objSink();
	out << node->getSymbol();

	if (mDeclaringVariables && node->getType().isArray())
	out << arrayBrackets(node->getType());
	}

	void TOutputGLSL::visitConstantUnion(TIntermConstantUnion* node)
	{
	writeConstantUnion(node->getType(), node->getUnionArrayPointer());
	}

	bool TOutputGLSL::visitBinary(Visit visit, TIntermBinary* node)
	{
	bool visitChildren = true;
	TInfoSinkBase& out = objSink();
	switch (node->getOp())
	{
	case EOpInitialize:
	if (visit == InVisit)
	{
	out << " = ";
	// RHS of initialize is not being declared.
	mDeclaringVariables = false;
	}
	break;
	case EOpAssign: writeTriplet(visit, "(", " = ", ")"); break;
	case EOpAddAssign: writeTriplet(visit, "(", " += ", ")"); break;
	case EOpSubAssign: writeTriplet(visit, "(", " -= ", ")"); break;
	case EOpDivAssign: writeTriplet(visit, "(", " /= ", ")"); break;
	// Notice the fall-through.
	case EOpMulAssign:
	case EOpVectorTimesMatrixAssign:
	case EOpVectorTimesScalarAssign:
	case EOpMatrixTimesScalarAssign:
	case EOpMatrixTimesMatrixAssign:
	writeTriplet(visit, "(", " *= ", ")");
	break;

	case EOpIndexDirect:
	case EOpIndexIndirect:
	writeTriplet(visit, NULL, "[", "]");
	break;
	case EOpIndexDirectStruct:
	if (visit == InVisit)
	{
	out << ".";
	// TODO(alokp): ASSERT
	out << node->getType().getFieldName();
	visitChildren = false;
	}
	break;
	case EOpVectorSwizzle:
	if (visit == InVisit)
	{
	out << ".";
	TIntermAggregate* rightChild = node->getRight()->getAsAggregate();
	TIntermSequence& sequence = rightChild->getSequence();
	for (TIntermSequence::iterator sit = sequence.begin(); sit != sequence.end(); ++sit)
	{
	TIntermConstantUnion* element = (*sit)->getAsConstantUnion();
	ASSERT(element->getBasicType() == EbtInt);
	ASSERT(element->getNominalSize() == 1);
	const ConstantUnion& data = element->getUnionArrayPointer()[0];
	ASSERT(data.getType() == EbtInt);
	switch (data.getIConst())
	{
	case 0: out << "x"; break;
	case 1: out << "y"; break;
	case 2: out << "z"; break;
	case 3: out << "w"; break;
	default: UNREACHABLE(); break;
	}
	}
	visitChildren = false;
	}
	break;

	case EOpAdd: writeTriplet(visit, "(", " + ", ")"); break;
	case EOpSub: writeTriplet(visit, "(", " - ", ")"); break;
	case EOpMul: writeTriplet(visit, "(", " * ", ")"); break;
	case EOpDiv: writeTriplet(visit, "(", " / ", ")"); break;
	case EOpMod: UNIMPLEMENTED(); break;
	case EOpEqual: writeTriplet(visit, "(", " == ", ")"); break;
	case EOpNotEqual: writeTriplet(visit, "(", " != ", ")"); break;
	case EOpLessThan: writeTriplet(visit, "(", " < ", ")"); break;
	case EOpGreaterThan: writeTriplet(visit, "(", " > ", ")"); break;
	case EOpLessThanEqual: writeTriplet(visit, "(", " <= ", ")"); break;
	case EOpGreaterThanEqual: writeTriplet(visit, "(", " >= ", ")"); break;

	// Notice the fall-through.
	case EOpVectorTimesScalar:
	case EOpVectorTimesMatrix:
	case EOpMatrixTimesVector:
	case EOpMatrixTimesScalar:
	case EOpMatrixTimesMatrix:
	writeTriplet(visit, "(", " * ", ")");
	break;

	case EOpLogicalOr: writeTriplet(visit, "(", " \|\| ", ")"); break;
	case EOpLogicalXor: writeTriplet(visit, "(", " ^^ ", ")"); break;
	case EOpLogicalAnd: writeTriplet(visit, "(", " && ", ")"); break;
	default: UNREACHABLE(); break;
	}

	return visitChildren;
	}

	bool TOutputGLSL::visitUnary(Visit visit, TIntermUnary* node)
	{
	switch (node->getOp())
	{
	case EOpNegative: writeTriplet(visit, "(-", NULL, ")"); break;
	case EOpVectorLogicalNot: writeTriplet(visit, "not(", NULL, ")"); break;
	case EOpLogicalNot: writeTriplet(visit, "(!", NULL, ")"); break;

	case EOpPostIncrement: writeTriplet(visit, "(", NULL, "++)"); break;
	case EOpPostDecrement: writeTriplet(visit, "(", NULL, "--)"); break;
	case EOpPreIncrement: writeTriplet(visit, "(++", NULL, ")"); break;
	case EOpPreDecrement: writeTriplet(visit, "(--", NULL, ")"); break;

	case EOpConvIntToBool:
	case EOpConvFloatToBool:
	switch (node->getOperand()->getType().getNominalSize())
	{
	case 1: writeTriplet(visit, "bool(", NULL, ")"); break;
	case 2: writeTriplet(visit, "bvec2(", NULL, ")"); break;
	case 3: writeTriplet(visit, "bvec3(", NULL, ")"); break;
	case 4: writeTriplet(visit, "bvec4(", NULL, ")"); break;
	default: UNREACHABLE();
	}
	break;
	case EOpConvBoolToFloat:
	case EOpConvIntToFloat:
	switch (node->getOperand()->getType().getNominalSize())
	{
	case 1: writeTriplet(visit, "float(", NULL, ")"); break;
	case 2: writeTriplet(visit, "vec2(", NULL, ")"); break;
	case 3: writeTriplet(visit, "vec3(", NULL, ")"); break;
	case 4: writeTriplet(visit, "vec4(", NULL, ")"); break;
	default: UNREACHABLE();
	}
	break;
	case EOpConvFloatToInt:
	case EOpConvBoolToInt:
	switch (node->getOperand()->getType().getNominalSize())
	{
	case 1: writeTriplet(visit, "int(", NULL, ")"); break;
	case 2: writeTriplet(visit, "ivec2(", NULL, ")"); break;
	case 3: writeTriplet(visit, "ivec3(", NULL, ")"); break;
	case 4: writeTriplet(visit, "ivec4(", NULL, ")"); break;
	default: UNREACHABLE();
	}
	break;

	case EOpRadians: writeTriplet(visit, "radians(", NULL, ")"); break;
	case EOpDegrees: writeTriplet(visit, "degrees(", NULL, ")"); break;
	case EOpSin: writeTriplet(visit, "sin(", NULL, ")"); break;
	case EOpCos: writeTriplet(visit, "cos(", NULL, ")"); break;
	case EOpTan: writeTriplet(visit, "tan(", NULL, ")"); break;
	case EOpAsin: writeTriplet(visit, "asin(", NULL, ")"); break;
	case EOpAcos: writeTriplet(visit, "acos(", NULL, ")"); break;
	case EOpAtan: writeTriplet(visit, "atan(", NULL, ")"); break;

	case EOpExp: writeTriplet(visit, "exp(", NULL, ")"); break;
	case EOpLog: writeTriplet(visit, "log(", NULL, ")"); break;
	case EOpExp2: writeTriplet(visit, "exp2(", NULL, ")"); break;
	case EOpLog2: writeTriplet(visit, "log2(", NULL, ")"); break;
	case EOpSqrt: writeTriplet(visit, "sqrt(", NULL, ")"); break;
	case EOpInverseSqrt: writeTriplet(visit, "inversesqrt(", NULL, ")"); break;

	case EOpAbs: writeTriplet(visit, "abs(", NULL, ")"); break;
	case EOpSign: writeTriplet(visit, "sign(", NULL, ")"); break;
	case EOpFloor: writeTriplet(visit, "floor(", NULL, ")"); break;
	case EOpCeil: writeTriplet(visit, "ceil(", NULL, ")"); break;
	case EOpFract: writeTriplet(visit, "fract(", NULL, ")"); break;

	case EOpLength: writeTriplet(visit, "length(", NULL, ")"); break;
	case EOpNormalize: writeTriplet(visit, "normalize(", NULL, ")"); break;

	case EOpDFdx: writeTriplet(visit, "dFdx(", NULL, ")"); break;
	case EOpDFdy: writeTriplet(visit, "dFdy(", NULL, ")"); break;
	case EOpFwidth: writeTriplet(visit, "fwidth(", NULL, ")"); break;

	case EOpAny: writeTriplet(visit, "any(", NULL, ")"); break;
	case EOpAll: writeTriplet(visit, "all(", NULL, ")"); break;

	default: UNREACHABLE(); break;
	}

	return true;
	}

	bool TOutputGLSL::visitSelection(Visit visit, TIntermSelection* node)
	{
	TInfoSinkBase& out = objSink();

	if (node->usesTernaryOperator())
	{
	// Notice two brackets at the beginning and end. The outer ones
	// encapsulate the whole ternary expression. This preserves the
	// order of precedence when ternary expressions are used in a
	// compound expression, i.e., c = 2 * (a < b ? 1 : 2).
	out << "((";
	node->getCondition()->traverse(this);
	out << ") ? (";
	node->getTrueBlock()->traverse(this);
	out << ") : (";
	node->getFalseBlock()->traverse(this);
	out << "))";
	}
	else
	{
	out << "if (";
	node->getCondition()->traverse(this);
	out << ")\n";

	incrementDepth();
	visitCodeBlock(node->getTrueBlock());

	if (node->getFalseBlock())
	{
	out << "else\n";
	visitCodeBlock(node->getFalseBlock());
	}
	decrementDepth();
	}
	return false;
	}

	bool TOutputGLSL::visitAggregate(Visit visit, TIntermAggregate* node)
	{
	bool visitChildren = true;
	TInfoSinkBase& out = objSink();
	switch (node->getOp())
	{
	case EOpSequence: {
	// Scope the sequences except when at the global scope.
	if (depth > 0) out << "{\n";

	incrementDepth();
	const TIntermSequence& sequence = node->getSequence();
	for (TIntermSequence::const_iterator iter = sequence.begin();
	iter != sequence.end(); ++iter)
	{
	TIntermNode* node = *iter;
	ASSERT(node != NULL);
	node->traverse(this);

	if (isSingleStatement(node))
	out << ";\n";
	}
	decrementDepth();

	// Scope the sequences except when at the global scope.
	if (depth > 0) out << "}\n";
	visitChildren = false;
	break;
	}
	case EOpPrototype: {
	// Function declaration.
	ASSERT(visit == PreVisit);
	TString returnType = getTypeName(node->getType());
	out << returnType << " " << node->getName();

	out << "(";
	writeFunctionParameters(node->getSequence());
	out << ")";

	visitChildren = false;
	break;
	}
	case EOpFunction: {
	// Function definition.
	ASSERT(visit == PreVisit);
	TString returnType = getTypeName(node->getType());
	TString functionName = TFunction::unmangleName(node->getName());
	out << returnType << " " << functionName;

	incrementDepth();
	// Function definition node contains one or two children nodes
	// representing function parameters and function body. The latter
	// is not present in case of empty function bodies.
	const TIntermSequence& sequence = node->getSequence();
	ASSERT((sequence.size() == 1) \|\| (sequence.size() == 2));
	TIntermSequence::const_iterator seqIter = sequence.begin();

	// Traverse function parameters.
	TIntermAggregate* params = (*seqIter)->getAsAggregate();
	ASSERT(params != NULL);
	ASSERT(params->getOp() == EOpParameters);
	params->traverse(this);

	// Traverse function body.
	TIntermAggregate* body = ++seqIter != sequence.end() ?
	(*seqIter)->getAsAggregate() : NULL;
	visitCodeBlock(body);
	decrementDepth();

	// Fully processed; no need to visit children.
	visitChildren = false;
	break;
	}
	case EOpFunctionCall:
	// Function call.
	if (visit == PreVisit)
	{
	TString functionName = TFunction::unmangleName(node->getName());
	out << functionName << "(";
	}
	else if (visit == InVisit)
	{
	out << ", ";
	}
	else
	{
	out << ")";
	}
	break;
	case EOpParameters: {
	// Function parameters.
	ASSERT(visit == PreVisit);
	out << "(";
	writeFunctionParameters(node->getSequence());
	out << ")";
	visitChildren = false;
	break;
	}
	case EOpDeclaration: {
	// Variable declaration.
	if (visit == PreVisit)
	{
	const TIntermSequence& sequence = node->getSequence();
	const TIntermTyped* variable = sequence.front()->getAsTyped();
	writeVariableType(variable->getType());
	out << " ";
	mDeclaringVariables = true;
	}
	else if (visit == InVisit)
	{
	out << ", ";
	mDeclaringVariables = true;
	}
	else
	{
	mDeclaringVariables = false;
	}
	break;
	}
	case EOpConstructFloat: writeTriplet(visit, "float(", NULL, ")"); break;
	case EOpConstructVec2: writeTriplet(visit, "vec2(", ", ", ")"); break;
	case EOpConstructVec3: writeTriplet(visit, "vec3(", ", ", ")"); break;
	case EOpConstructVec4: writeTriplet(visit, "vec4(", ", ", ")"); break;
	case EOpConstructBool: writeTriplet(visit, "bool(", NULL, ")"); break;
	case EOpConstructBVec2: writeTriplet(visit, "bvec2(", ", ", ")"); break;
	case EOpConstructBVec3: writeTriplet(visit, "bvec3(", ", ", ")"); break;
	case EOpConstructBVec4: writeTriplet(visit, "bvec4(", ", ", ")"); break;
	case EOpConstructInt: writeTriplet(visit, "int(", NULL, ")"); break;
	case EOpConstructIVec2: writeTriplet(visit, "ivec2(", ", ", ")"); break;
	case EOpConstructIVec3: writeTriplet(visit, "ivec3(", ", ", ")"); break;
	case EOpConstructIVec4: writeTriplet(visit, "ivec4(", ", ", ")"); break;
	case EOpConstructMat2: writeTriplet(visit, "mat2(", ", ", ")"); break;
	case EOpConstructMat3: writeTriplet(visit, "mat3(", ", ", ")"); break;
	case EOpConstructMat4: writeTriplet(visit, "mat4(", ", ", ")"); break;
	case EOpConstructStruct:
	if (visit == PreVisit)
	{
	const TType& type = node->getType();
	ASSERT(type.getBasicType() == EbtStruct);
	out << type.getTypeName() << "(";
	}
	else if (visit == InVisit)
	{
	out << ", ";
	}
	else
	{
	out << ")";
	}
	break;

	case EOpLessThan: writeTriplet(visit, "lessThan(", ", ", ")"); break;
	case EOpGreaterThan: writeTriplet(visit, "greaterThan(", ", ", ")"); break;
	case EOpLessThanEqual: writeTriplet(visit, "lessThanEqual(", ", ", ")"); break;
	case EOpGreaterThanEqual: writeTriplet(visit, "greaterThanEqual(", ", ", ")"); break;
	case EOpVectorEqual: writeTriplet(visit, "equal(", ", ", ")"); break;
	case EOpVectorNotEqual: writeTriplet(visit, "notEqual(", ", ", ")"); break;
	case EOpComma: writeTriplet(visit, NULL, ", ", NULL); break;

	case EOpMod: writeTriplet(visit, "mod(", ", ", ")"); break;
	case EOpPow: writeTriplet(visit, "pow(", ", ", ")"); break;
	case EOpAtan: writeTriplet(visit, "atan(", ", ", ")"); break;
	case EOpMin: writeTriplet(visit, "min(", ", ", ")"); break;
	case EOpMax: writeTriplet(visit, "max(", ", ", ")"); break;
	case EOpClamp: writeTriplet(visit, "clamp(", ", ", ")"); break;
	case EOpMix: writeTriplet(visit, "mix(", ", ", ")"); break;
	case EOpStep: writeTriplet(visit, "step(", ", ", ")"); break;
	case EOpSmoothStep: writeTriplet(visit, "smoothstep(", ", ", ")"); break;

	case EOpDistance: writeTriplet(visit, "distance(", ", ", ")"); break;
	case EOpDot: writeTriplet(visit, "dot(", ", ", ")"); break;
	case EOpCross: writeTriplet(visit, "cross(", ", ", ")"); break;
	case EOpFaceForward: writeTriplet(visit, "faceforward(", ", ", ")"); break;
	case EOpReflect: writeTriplet(visit, "reflect(", ", ", ")"); break;
	case EOpRefract: writeTriplet(visit, "refract(", ", ", ")"); break;
	case EOpMul: writeTriplet(visit, "matrixCompMult(", ", ", ")"); break;

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

	bool TOutputGLSL::visitLoop(Visit visit, TIntermLoop* node)
	{
	TInfoSinkBase& out = objSink();

	incrementDepth();
	// Loop header.
	TLoopType loopType = node->getType();
	if (loopType == ELoopFor) // for loop
	{
	out << "for (";
	if (node->getInit())
	node->getInit()->traverse(this);
	out << "; ";

	if (node->getCondition())
	node->getCondition()->traverse(this);
	out << "; ";

	if (node->getExpression())
	node->getExpression()->traverse(this);
	out << ")\n";
	}
	else if (loopType == ELoopWhile) // while loop
	{
	out << "while (";
	ASSERT(node->getCondition() != NULL);
	node->getCondition()->traverse(this);
	out << ")\n";
	}
	else // do-while loop
	{
	ASSERT(loopType == ELoopDoWhile);
	out << "do\n";
	}

	// Loop body.
	visitCodeBlock(node->getBody());

	// Loop footer.
	if (loopType == ELoopDoWhile) // do-while loop
	{
	out << "while (";
	ASSERT(node->getCondition() != NULL);
	node->getCondition()->traverse(this);
	out << ");\n";
	}
	decrementDepth();

	// No need to visit children. They have been already processed in
	// this function.
	return false;
	}

	bool TOutputGLSL::visitBranch(Visit visit, TIntermBranch* node)
	{
	switch (node->getFlowOp())
	{
	case EOpKill: writeTriplet(visit, "discard", NULL, NULL); break;
	case EOpBreak: writeTriplet(visit, "break", NULL, NULL); break;
	case EOpContinue: writeTriplet(visit, "continue", NULL, NULL); break;
	case EOpReturn: writeTriplet(visit, "return ", NULL, NULL); break;
	default: UNREACHABLE(); break;
	}

	return true;
	}

	void TOutputGLSL::visitCodeBlock(TIntermNode* node) {
	TInfoSinkBase &out = objSink();
	if (node != NULL)
	{
	node->traverse(this);
	// Single statements not part of a sequence need to be terminated
	// with semi-colon.
	if (isSingleStatement(node))
	out << ";\n";
	}
	else
	{
	out << "{\n}\n"; // Empty code block.
	}
	}