diff --git a/src/GLES2/compiler/ParseHelper.cpp b/src/GLES2/compiler/ParseHelper.cpp
new file mode 100644
index 0000000..2107300
--- /dev/null
+++ b/src/GLES2/compiler/ParseHelper.cpp
@@ -0,0 +1,1524 @@
+//
+// Copyright (c) 2002-2012 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/ParseHelper.h"
+
+#include <stdarg.h>
+#include <stdio.h>
+
+#include "compiler/glslang.h"
+#include "compiler/preprocessor/SourceLocation.h"
+
+///////////////////////////////////////////////////////////////////////
+//
+// Sub- vector and matrix fields
+//
+////////////////////////////////////////////////////////////////////////
+
+//
+// Look at a '.' field selector string and change it into offsets
+// for a vector.
+//
+bool TParseContext::parseVectorFields(const TString& compString, int vecSize, TVectorFields& fields, int line)
+{
+    fields.num = (int) compString.size();
+    if (fields.num > 4) {
+        error(line, "illegal vector field selection", compString.c_str());
+        return false;
+    }
+
+    enum {
+        exyzw,
+        ergba,
+        estpq,
+    } fieldSet[4];
+
+    for (int i = 0; i < fields.num; ++i) {
+        switch (compString[i])  {
+        case 'x': 
+            fields.offsets[i] = 0;
+            fieldSet[i] = exyzw;
+            break;
+        case 'r': 
+            fields.offsets[i] = 0;
+            fieldSet[i] = ergba;
+            break;
+        case 's':
+            fields.offsets[i] = 0;
+            fieldSet[i] = estpq;
+            break;
+        case 'y': 
+            fields.offsets[i] = 1;
+            fieldSet[i] = exyzw;
+            break;
+        case 'g': 
+            fields.offsets[i] = 1;
+            fieldSet[i] = ergba;
+            break;
+        case 't':
+            fields.offsets[i] = 1;
+            fieldSet[i] = estpq;
+            break;
+        case 'z': 
+            fields.offsets[i] = 2;
+            fieldSet[i] = exyzw;
+            break;
+        case 'b': 
+            fields.offsets[i] = 2;
+            fieldSet[i] = ergba;
+            break;
+        case 'p':
+            fields.offsets[i] = 2;
+            fieldSet[i] = estpq;
+            break;
+        
+        case 'w': 
+            fields.offsets[i] = 3;
+            fieldSet[i] = exyzw;
+            break;
+        case 'a': 
+            fields.offsets[i] = 3;
+            fieldSet[i] = ergba;
+            break;
+        case 'q':
+            fields.offsets[i] = 3;
+            fieldSet[i] = estpq;
+            break;
+        default:
+            error(line, "illegal vector field selection", compString.c_str());
+            return false;
+        }
+    }
+
+    for (int i = 0; i < fields.num; ++i) {
+        if (fields.offsets[i] >= vecSize) {
+            error(line, "vector field selection out of range",  compString.c_str());
+            return false;
+        }
+
+        if (i > 0) {
+            if (fieldSet[i] != fieldSet[i-1]) {
+                error(line, "illegal - vector component fields not from the same set", compString.c_str());
+                return false;
+            }
+        }
+    }
+
+    return true;
+}
+
+
+//
+// Look at a '.' field selector string and change it into offsets
+// for a matrix.
+//
+bool TParseContext::parseMatrixFields(const TString& compString, int matSize, TMatrixFields& fields, int line)
+{
+    fields.wholeRow = false;
+    fields.wholeCol = false;
+    fields.row = -1;
+    fields.col = -1;
+
+    if (compString.size() != 2) {
+        error(line, "illegal length of matrix field selection", compString.c_str());
+        return false;
+    }
+
+    if (compString[0] == '_') {
+        if (compString[1] < '0' || compString[1] > '3') {
+            error(line, "illegal matrix field selection", compString.c_str());
+            return false;
+        }
+        fields.wholeCol = true;
+        fields.col = compString[1] - '0';
+    } else if (compString[1] == '_') {
+        if (compString[0] < '0' || compString[0] > '3') {
+            error(line, "illegal matrix field selection", compString.c_str());
+            return false;
+        }
+        fields.wholeRow = true;
+        fields.row = compString[0] - '0';
+    } else {
+        if (compString[0] < '0' || compString[0] > '3' ||
+            compString[1] < '0' || compString[1] > '3') {
+            error(line, "illegal matrix field selection", compString.c_str());
+            return false;
+        }
+        fields.row = compString[0] - '0';
+        fields.col = compString[1] - '0';
+    }
+
+    if (fields.row >= matSize || fields.col >= matSize) {
+        error(line, "matrix field selection out of range", compString.c_str());
+        return false;
+    }
+
+    return true;
+}
+
+///////////////////////////////////////////////////////////////////////
+//
+// Errors
+//
+////////////////////////////////////////////////////////////////////////
+
+//
+// Track whether errors have occurred.
+//
+void TParseContext::recover()
+{
+}
+
+//
+// Used by flex/bison to output all syntax and parsing errors.
+//
+void TParseContext::error(TSourceLoc loc,
+                          const char* reason, const char* token, 
+                          const char* extraInfo)
+{
+    pp::SourceLocation srcLoc;
+    DecodeSourceLoc(loc, &srcLoc.file, &srcLoc.line);
+    diagnostics.writeInfo(pp::Diagnostics::PP_ERROR,
+                          srcLoc, reason, token, extraInfo);
+
+}
+
+void TParseContext::warning(TSourceLoc loc,
+                            const char* reason, const char* token,
+                            const char* extraInfo) {
+    pp::SourceLocation srcLoc;
+    DecodeSourceLoc(loc, &srcLoc.file, &srcLoc.line);
+    diagnostics.writeInfo(pp::Diagnostics::PP_WARNING,
+                          srcLoc, reason, token, extraInfo);
+}
+
+void TParseContext::trace(const char* str)
+{
+    diagnostics.writeDebug(str);
+}
+
+//
+// Same error message for all places assignments don't work.
+//
+void TParseContext::assignError(int line, const char* op, TString left, TString right)
+{
+    std::stringstream extraInfoStream;
+    extraInfoStream << "cannot convert from '" << right << "' to '" << left << "'";
+    std::string extraInfo = extraInfoStream.str();
+    error(line, "", op, extraInfo.c_str());
+}
+
+//
+// Same error message for all places unary operations don't work.
+//
+void TParseContext::unaryOpError(int line, const char* op, TString operand)
+{
+    std::stringstream extraInfoStream;
+    extraInfoStream << "no operation '" << op << "' exists that takes an operand of type " << operand 
+                    << " (or there is no acceptable conversion)";
+    std::string extraInfo = extraInfoStream.str();
+    error(line, " wrong operand type", op, extraInfo.c_str());
+}
+
+//
+// Same error message for all binary operations don't work.
+//
+void TParseContext::binaryOpError(int line, const char* op, TString left, TString right)
+{
+    std::stringstream extraInfoStream;
+    extraInfoStream << "no operation '" << op << "' exists that takes a left-hand operand of type '" << left 
+                    << "' and a right operand of type '" << right << "' (or there is no acceptable conversion)";
+    std::string extraInfo = extraInfoStream.str();
+    error(line, " wrong operand types ", op, extraInfo.c_str()); 
+}
+
+bool TParseContext::precisionErrorCheck(int line, TPrecision precision, TBasicType type){
+    if (!checksPrecisionErrors)
+        return false;
+    switch( type ){
+    case EbtFloat:
+        if( precision == EbpUndefined ){
+            error( line, "No precision specified for (float)", "" );
+            return true;
+        }
+        break;
+    case EbtInt:
+        if( precision == EbpUndefined ){
+            error( line, "No precision specified (int)", "" );
+            return true;
+        }
+        break;
+    default:
+        return false;
+    }
+    return false;
+}
+
+//
+// Both test and if necessary, spit out an error, to see if the node is really
+// an l-value that can be operated on this way.
+//
+// Returns true if the was an error.
+//
+bool TParseContext::lValueErrorCheck(int line, const char* op, TIntermTyped* node)
+{
+    TIntermSymbol* symNode = node->getAsSymbolNode();
+    TIntermBinary* binaryNode = node->getAsBinaryNode();
+
+    if (binaryNode) {
+        bool errorReturn;
+
+        switch(binaryNode->getOp()) {
+        case EOpIndexDirect:
+        case EOpIndexIndirect:
+        case EOpIndexDirectStruct:
+            return lValueErrorCheck(line, op, binaryNode->getLeft());
+        case EOpVectorSwizzle:
+            errorReturn = lValueErrorCheck(line, op, binaryNode->getLeft());
+            if (!errorReturn) {
+                int offset[4] = {0,0,0,0};
+
+                TIntermTyped* rightNode = binaryNode->getRight();
+                TIntermAggregate *aggrNode = rightNode->getAsAggregate();
+                
+                for (TIntermSequence::iterator p = aggrNode->getSequence().begin(); 
+                                               p != aggrNode->getSequence().end(); p++) {
+                    int value = (*p)->getAsTyped()->getAsConstantUnion()->getUnionArrayPointer()->getIConst();
+                    offset[value]++;     
+                    if (offset[value] > 1) {
+                        error(line, " l-value of swizzle cannot have duplicate components", op);
+
+                        return true;
+                    }
+                }
+            } 
+
+            return errorReturn;
+        default: 
+            break;
+        }
+        error(line, " l-value required", op);
+
+        return true;
+    }
+
+
+    const char* symbol = 0;
+    if (symNode != 0)
+        symbol = symNode->getSymbol().c_str();
+
+    const char* message = 0;
+    switch (node->getQualifier()) {
+    case EvqConst:          message = "can't modify a const";        break;
+    case EvqConstReadOnly:  message = "can't modify a const";        break;
+    case EvqAttribute:      message = "can't modify an attribute";   break;
+    case EvqUniform:        message = "can't modify a uniform";      break;
+    case EvqVaryingIn:      message = "can't modify a varying";      break;
+    case EvqInput:          message = "can't modify an input";       break;
+    case EvqFragCoord:      message = "can't modify gl_FragCoord";   break;
+    case EvqFrontFacing:    message = "can't modify gl_FrontFacing"; break;
+    case EvqPointCoord:     message = "can't modify gl_PointCoord";  break;
+    default:
+
+        //
+        // Type that can't be written to?
+        //
+        switch (node->getBasicType()) {
+        case EbtSampler2D:
+        case EbtSamplerCube:
+            message = "can't modify a sampler";
+            break;
+        case EbtVoid:
+            message = "can't modify void";
+            break;
+        default: 
+            break;
+        }
+    }
+
+    if (message == 0 && binaryNode == 0 && symNode == 0) {
+        error(line, " l-value required", op);
+
+        return true;
+    }
+
+
+    //
+    // Everything else is okay, no error.
+    //
+    if (message == 0)
+        return false;
+
+    //
+    // If we get here, we have an error and a message.
+    //
+    if (symNode) {
+        std::stringstream extraInfoStream;
+        extraInfoStream << "\"" << symbol << "\" (" << message << ")";
+        std::string extraInfo = extraInfoStream.str();
+        error(line, " l-value required", op, extraInfo.c_str());
+    }
+    else {
+        std::stringstream extraInfoStream;
+        extraInfoStream << "(" << message << ")";
+        std::string extraInfo = extraInfoStream.str();
+        error(line, " l-value required", op, extraInfo.c_str());
+    }
+
+    return true;
+}
+
+//
+// Both test, and if necessary spit out an error, to see if the node is really
+// a constant.
+//
+// Returns true if the was an error.
+//
+bool TParseContext::constErrorCheck(TIntermTyped* node)
+{
+    if (node->getQualifier() == EvqConst)
+        return false;
+
+    error(node->getLine(), "constant expression required", "");
+
+    return true;
+}
+
+//
+// Both test, and if necessary spit out an error, to see if the node is really
+// an integer.
+//
+// Returns true if the was an error.
+//
+bool TParseContext::integerErrorCheck(TIntermTyped* node, const char* token)
+{
+    if (node->getBasicType() == EbtInt && node->getNominalSize() == 1)
+        return false;
+
+    error(node->getLine(), "integer expression required", token);
+
+    return true;
+}
+
+//
+// Both test, and if necessary spit out an error, to see if we are currently
+// globally scoped.
+//
+// Returns true if the was an error.
+//
+bool TParseContext::globalErrorCheck(int line, bool global, const char* token)
+{
+    if (global)
+        return false;
+
+    error(line, "only allowed at global scope", token);
+
+    return true;
+}
+
+//
+// For now, keep it simple:  if it starts "gl_", it's reserved, independent
+// of scope.  Except, if the symbol table is at the built-in push-level,
+// which is when we are parsing built-ins.
+// Also checks for "webgl_" and "_webgl_" reserved identifiers if parsing a
+// webgl shader.
+//
+// Returns true if there was an error.
+//
+bool TParseContext::reservedErrorCheck(int line, const TString& identifier)
+{
+    static const char* reservedErrMsg = "reserved built-in name";
+    if (!symbolTable.atBuiltInLevel()) {
+        if (identifier.compare(0, 3, "gl_") == 0) {
+            error(line, reservedErrMsg, "gl_");
+            return true;
+        }
+        if (shaderSpec == SH_WEBGL_SPEC) {
+            if (identifier.compare(0, 6, "webgl_") == 0) {
+                error(line, reservedErrMsg, "webgl_");
+                return true;
+            }
+            if (identifier.compare(0, 7, "_webgl_") == 0) {
+                error(line, reservedErrMsg, "_webgl_");
+                return true;
+            }
+        }
+        if (identifier.find("__") != TString::npos) {
+            error(line, "identifiers containing two consecutive underscores (__) are reserved as possible future keywords", identifier.c_str());
+            return true;
+        }
+    }
+
+    return false;
+}
+
+//
+// Make sure there is enough data provided to the constructor to build
+// something of the type of the constructor.  Also returns the type of
+// the constructor.
+//
+// Returns true if there was an error in construction.
+//
+bool TParseContext::constructorErrorCheck(int line, TIntermNode* node, TFunction& function, TOperator op, TType* type)
+{
+    *type = function.getReturnType();
+
+    bool constructingMatrix = false;
+    switch(op) {
+    case EOpConstructMat2:
+    case EOpConstructMat3:
+    case EOpConstructMat4:
+        constructingMatrix = true;
+        break;
+    default: 
+        break;
+    }
+
+    //
+    // Note: It's okay to have too many components available, but not okay to have unused
+    // arguments.  'full' will go to true when enough args have been seen.  If we loop
+    // again, there is an extra argument, so 'overfull' will become true.
+    //
+
+    int size = 0;
+    bool constType = true;
+    bool full = false;
+    bool overFull = false;
+    bool matrixInMatrix = false;
+    bool arrayArg = false;
+    for (int i = 0; i < function.getParamCount(); ++i) {
+        const TParameter& param = function.getParam(i);
+        size += param.type->getObjectSize();
+        
+        if (constructingMatrix && param.type->isMatrix())
+            matrixInMatrix = true;
+        if (full)
+            overFull = true;
+        if (op != EOpConstructStruct && !type->isArray() && size >= type->getObjectSize())
+            full = true;
+        if (param.type->getQualifier() != EvqConst)
+            constType = false;
+        if (param.type->isArray())
+            arrayArg = true;
+    }
+    
+    if (constType)
+        type->setQualifier(EvqConst);
+
+    if (type->isArray() && type->getArraySize() != function.getParamCount()) {
+        error(line, "array constructor needs one argument per array element", "constructor");
+        return true;
+    }
+
+    if (arrayArg && op != EOpConstructStruct) {
+        error(line, "constructing from a non-dereferenced array", "constructor");
+        return true;
+    }
+
+    if (matrixInMatrix && !type->isArray()) {
+        if (function.getParamCount() != 1) {
+          error(line, "constructing matrix from matrix can only take one argument", "constructor");
+          return true;
+        }
+    }
+
+    if (overFull) {
+        error(line, "too many arguments", "constructor");
+        return true;
+    }
+    
+    if (op == EOpConstructStruct && !type->isArray() && int(type->getStruct()->size()) != function.getParamCount()) {
+        error(line, "Number of constructor parameters does not match the number of structure fields", "constructor");
+        return true;
+    }
+
+    if (!type->isMatrix() || !matrixInMatrix) {
+        if ((op != EOpConstructStruct && size != 1 && size < type->getObjectSize()) ||
+            (op == EOpConstructStruct && size < type->getObjectSize())) {
+            error(line, "not enough data provided for construction", "constructor");
+            return true;
+        }
+    }
+
+    TIntermTyped *typed = node ? node->getAsTyped() : 0;
+    if (typed == 0) {
+        error(line, "constructor argument does not have a type", "constructor");
+        return true;
+    }
+    if (op != EOpConstructStruct && IsSampler(typed->getBasicType())) {
+        error(line, "cannot convert a sampler", "constructor");
+        return true;
+    }
+    if (typed->getBasicType() == EbtVoid) {
+        error(line, "cannot convert a void", "constructor");
+        return true;
+    }
+
+    return false;
+}
+
+// This function checks to see if a void variable has been declared and raise an error message for such a case
+//
+// returns true in case of an error
+//
+bool TParseContext::voidErrorCheck(int line, const TString& identifier, const TPublicType& pubType)
+{
+    if (pubType.type == EbtVoid) {
+        error(line, "illegal use of type 'void'", identifier.c_str());
+        return true;
+    } 
+
+    return false;
+}
+
+// This function checks to see if the node (for the expression) contains a scalar boolean expression or not
+//
+// returns true in case of an error
+//
+bool TParseContext::boolErrorCheck(int line, const TIntermTyped* type)
+{
+    if (type->getBasicType() != EbtBool || type->isArray() || type->isMatrix() || type->isVector()) {
+        error(line, "boolean expression expected", "");
+        return true;
+    } 
+
+    return false;
+}
+
+// This function checks to see if the node (for the expression) contains a scalar boolean expression or not
+//
+// returns true in case of an error
+//
+bool TParseContext::boolErrorCheck(int line, const TPublicType& pType)
+{
+    if (pType.type != EbtBool || pType.array || pType.matrix || (pType.size > 1)) {
+        error(line, "boolean expression expected", "");
+        return true;
+    } 
+
+    return false;
+}
+
+bool TParseContext::samplerErrorCheck(int line, const TPublicType& pType, const char* reason)
+{
+    if (pType.type == EbtStruct) {
+        if (containsSampler(*pType.userDef)) {
+            error(line, reason, getBasicString(pType.type), "(structure contains a sampler)");
+        
+            return true;
+        }
+        
+        return false;
+    } else if (IsSampler(pType.type)) {
+        error(line, reason, getBasicString(pType.type));
+
+        return true;
+    }
+
+    return false;
+}
+
+bool TParseContext::structQualifierErrorCheck(int line, const TPublicType& pType)
+{
+    if ((pType.qualifier == EvqVaryingIn || pType.qualifier == EvqVaryingOut || pType.qualifier == EvqAttribute) &&
+        pType.type == EbtStruct) {
+        error(line, "cannot be used with a structure", getQualifierString(pType.qualifier));
+        
+        return true;
+    }
+
+    if (pType.qualifier != EvqUniform && samplerErrorCheck(line, pType, "samplers must be uniform"))
+        return true;
+
+    return false;
+}
+
+bool TParseContext::parameterSamplerErrorCheck(int line, TQualifier qualifier, const TType& type)
+{
+    if ((qualifier == EvqOut || qualifier == EvqInOut) && 
+             type.getBasicType() != EbtStruct && IsSampler(type.getBasicType())) {
+        error(line, "samplers cannot be output parameters", type.getBasicString());
+        return true;
+    }
+
+    return false;
+}
+
+bool TParseContext::containsSampler(TType& type)
+{
+    if (IsSampler(type.getBasicType()))
+        return true;
+
+    if (type.getBasicType() == EbtStruct) {
+        TTypeList& structure = *type.getStruct();
+        for (unsigned int i = 0; i < structure.size(); ++i) {
+            if (containsSampler(*structure[i].type))
+                return true;
+        }
+    }
+
+    return false;
+}
+
+//
+// Do size checking for an array type's size.
+//
+// Returns true if there was an error.
+//
+bool TParseContext::arraySizeErrorCheck(int line, TIntermTyped* expr, int& size)
+{
+    TIntermConstantUnion* constant = expr->getAsConstantUnion();
+    if (constant == 0 || constant->getBasicType() != EbtInt) {
+        error(line, "array size must be a constant integer expression", "");
+        return true;
+    }
+
+    size = constant->getUnionArrayPointer()->getIConst();
+
+    if (size <= 0) {
+        error(line, "array size must be a positive integer", "");
+        size = 1;
+        return true;
+    }
+
+    return false;
+}
+
+//
+// See if this qualifier can be an array.
+//
+// Returns true if there is an error.
+//
+bool TParseContext::arrayQualifierErrorCheck(int line, TPublicType type)
+{
+    if ((type.qualifier == EvqAttribute) || (type.qualifier == EvqConst)) {
+        error(line, "cannot declare arrays of this qualifier", TType(type).getCompleteString().c_str());
+        return true;
+    }
+
+    return false;
+}
+
+//
+// See if this type can be an array.
+//
+// Returns true if there is an error.
+//
+bool TParseContext::arrayTypeErrorCheck(int line, TPublicType type)
+{
+    //
+    // Can the type be an array?
+    //
+    if (type.array) {
+        error(line, "cannot declare arrays of arrays", TType(type).getCompleteString().c_str());
+        return true;
+    }
+
+    return false;
+}
+
+//
+// Do all the semantic checking for declaring an array, with and 
+// without a size, and make the right changes to the symbol table.
+//
+// size == 0 means no specified size.
+//
+// Returns true if there was an error.
+//
+bool TParseContext::arrayErrorCheck(int line, TString& identifier, TPublicType type, TVariable*& variable)
+{
+    //
+    // Don't check for reserved word use until after we know it's not in the symbol table,
+    // because reserved arrays can be redeclared.
+    //
+
+    bool builtIn = false; 
+    bool sameScope = false;
+    TSymbol* symbol = symbolTable.find(identifier, &builtIn, &sameScope);
+    if (symbol == 0 || !sameScope) {
+        if (reservedErrorCheck(line, identifier))
+            return true;
+        
+        variable = new TVariable(&identifier, TType(type));
+
+        if (type.arraySize)
+            variable->getType().setArraySize(type.arraySize);
+
+        if (! symbolTable.insert(*variable)) {
+            delete variable;
+            error(line, "INTERNAL ERROR inserting new symbol", identifier.c_str());
+            return true;
+        }
+    } else {
+        if (! symbol->isVariable()) {
+            error(line, "variable expected", identifier.c_str());
+            return true;
+        }
+
+        variable = static_cast<TVariable*>(symbol);
+        if (! variable->getType().isArray()) {
+            error(line, "redeclaring non-array as array", identifier.c_str());
+            return true;
+        }
+        if (variable->getType().getArraySize() > 0) {
+            error(line, "redeclaration of array with size", identifier.c_str());
+            return true;
+        }
+        
+        if (! variable->getType().sameElementType(TType(type))) {
+            error(line, "redeclaration of array with a different type", identifier.c_str());
+            return true;
+        }
+
+        TType* t = variable->getArrayInformationType();
+        while (t != 0) {
+            if (t->getMaxArraySize() > type.arraySize) {
+                error(line, "higher index value already used for the array", identifier.c_str());
+                return true;
+            }
+            t->setArraySize(type.arraySize);
+            t = t->getArrayInformationType();
+        }
+
+        if (type.arraySize)
+            variable->getType().setArraySize(type.arraySize);
+    } 
+
+    if (voidErrorCheck(line, identifier, type))
+        return true;
+
+    return false;
+}
+
+bool TParseContext::arraySetMaxSize(TIntermSymbol *node, TType* type, int size, bool updateFlag, TSourceLoc line)
+{
+    bool builtIn = false;
+    TSymbol* symbol = symbolTable.find(node->getSymbol(), &builtIn);
+    if (symbol == 0) {
+        error(line, " undeclared identifier", node->getSymbol().c_str());
+        return true;
+    }
+    TVariable* variable = static_cast<TVariable*>(symbol);
+
+    type->setArrayInformationType(variable->getArrayInformationType());
+    variable->updateArrayInformationType(type);
+
+    // special casing to test index value of gl_FragData. If the accessed index is >= gl_MaxDrawBuffers
+    // its an error
+    if (node->getSymbol() == "gl_FragData") {
+        TSymbol* fragData = symbolTable.find("gl_MaxDrawBuffers", &builtIn);
+        ASSERT(fragData);
+
+        int fragDataValue = static_cast<TVariable*>(fragData)->getConstPointer()[0].getIConst();
+        if (fragDataValue <= size) {
+            error(line, "", "[", "gl_FragData can only have a max array size of up to gl_MaxDrawBuffers");
+            return true;
+        }
+    }
+
+    // we dont want to update the maxArraySize when this flag is not set, we just want to include this 
+    // node type in the chain of node types so that its updated when a higher maxArraySize comes in.
+    if (!updateFlag)
+        return false;
+
+    size++;
+    variable->getType().setMaxArraySize(size);
+    type->setMaxArraySize(size);
+    TType* tt = type;
+
+    while(tt->getArrayInformationType() != 0) {
+        tt = tt->getArrayInformationType();
+        tt->setMaxArraySize(size);
+    }
+
+    return false;
+}
+
+//
+// Enforce non-initializer type/qualifier rules.
+//
+// Returns true if there was an error.
+//
+bool TParseContext::nonInitConstErrorCheck(int line, TString& identifier, TPublicType& type, bool array)
+{
+    if (type.qualifier == EvqConst)
+    {
+        // Make the qualifier make sense.
+        type.qualifier = EvqTemporary;
+        
+        if (array)
+        {
+            error(line, "arrays may not be declared constant since they cannot be initialized", identifier.c_str());
+        }
+        else if (type.isStructureContainingArrays())
+        {
+            error(line, "structures containing arrays may not be declared constant since they cannot be initialized", identifier.c_str());
+        }
+        else
+        {
+            error(line, "variables with qualifier 'const' must be initialized", identifier.c_str());
+        }
+
+        return true;
+    }
+
+    return false;
+}
+
+//
+// Do semantic checking for a variable declaration that has no initializer,
+// and update the symbol table.
+//
+// Returns true if there was an error.
+//
+bool TParseContext::nonInitErrorCheck(int line, TString& identifier, TPublicType& type, TVariable*& variable)
+{
+    if (reservedErrorCheck(line, identifier))
+        recover();
+
+    variable = new TVariable(&identifier, TType(type));
+
+    if (! symbolTable.insert(*variable)) {
+        error(line, "redefinition", variable->getName().c_str());
+        delete variable;
+        variable = 0;
+        return true;
+    }
+
+    if (voidErrorCheck(line, identifier, type))
+        return true;
+
+    return false;
+}
+
+bool TParseContext::paramErrorCheck(int line, TQualifier qualifier, TQualifier paramQualifier, TType* type)
+{    
+    if (qualifier != EvqConst && qualifier != EvqTemporary) {
+        error(line, "qualifier not allowed on function parameter", getQualifierString(qualifier));
+        return true;
+    }
+    if (qualifier == EvqConst && paramQualifier != EvqIn) {
+        error(line, "qualifier not allowed with ", getQualifierString(qualifier), getQualifierString(paramQualifier));
+        return true;
+    }
+
+    if (qualifier == EvqConst)
+        type->setQualifier(EvqConstReadOnly);
+    else
+        type->setQualifier(paramQualifier);
+
+    return false;
+}
+
+bool TParseContext::extensionErrorCheck(int line, const TString& extension)
+{
+    const TExtensionBehavior& extBehavior = extensionBehavior();
+    TExtensionBehavior::const_iterator iter = extBehavior.find(extension.c_str());
+    if (iter == extBehavior.end()) {
+        error(line, "extension", extension.c_str(), "is not supported");
+        return true;
+    }
+    // In GLSL ES, an extension's default behavior is "disable".
+    if (iter->second == EBhDisable || iter->second == EBhUndefined) {
+        error(line, "extension", extension.c_str(), "is disabled");
+        return true;
+    }
+    if (iter->second == EBhWarn) {
+        warning(line, "extension", extension.c_str(), "is being used");
+        return false;
+    }
+
+    return false;
+}
+
+bool TParseContext::supportsExtension(const char* extension)
+{
+    const TExtensionBehavior& extbehavior = extensionBehavior();
+    TExtensionBehavior::const_iterator iter = extbehavior.find(extension);
+    return (iter != extbehavior.end());
+}
+
+void TParseContext::handleExtensionDirective(int line, const char* extName, const char* behavior)
+{
+    pp::SourceLocation loc;
+    DecodeSourceLoc(line, &loc.file, &loc.line);
+    directiveHandler.handleExtension(loc, extName, behavior);
+}
+
+void TParseContext::handlePragmaDirective(int line, const char* name, const char* value)
+{
+    pp::SourceLocation loc;
+    DecodeSourceLoc(line, &loc.file, &loc.line);
+    directiveHandler.handlePragma(loc, name, value);
+}
+
+/////////////////////////////////////////////////////////////////////////////////
+//
+// Non-Errors.
+//
+/////////////////////////////////////////////////////////////////////////////////
+
+//
+// Look up a function name in the symbol table, and make sure it is a function.
+//
+// Return the function symbol if found, otherwise 0.
+//
+const TFunction* TParseContext::findFunction(int line, TFunction* call, bool *builtIn)
+{
+    // First find by unmangled name to check whether the function name has been
+    // hidden by a variable name or struct typename.
+    const TSymbol* symbol = symbolTable.find(call->getName(), builtIn);
+    if (symbol == 0) {
+        symbol = symbolTable.find(call->getMangledName(), builtIn);
+    }
+
+    if (symbol == 0) {
+        error(line, "no matching overloaded function found", call->getName().c_str());
+        return 0;
+    }
+
+    if (!symbol->isFunction()) {
+        error(line, "function name expected", call->getName().c_str());
+        return 0;
+    }
+
+    return static_cast<const TFunction*>(symbol);
+}
+
+//
+// Initializers show up in several places in the grammar.  Have one set of
+// code to handle them here.
+//
+bool TParseContext::executeInitializer(TSourceLoc line, TString& identifier, TPublicType& pType, 
+                                       TIntermTyped* initializer, TIntermNode*& intermNode, TVariable* variable)
+{
+    TType type = TType(pType);
+
+    if (variable == 0) {
+        if (reservedErrorCheck(line, identifier))
+            return true;
+
+        if (voidErrorCheck(line, identifier, pType))
+            return true;
+
+        //
+        // add variable to symbol table
+        //
+        variable = new TVariable(&identifier, type);
+        if (! symbolTable.insert(*variable)) {
+            error(line, "redefinition", variable->getName().c_str());
+            return true;
+            // don't delete variable, it's used by error recovery, and the pool 
+            // pop will take care of the memory
+        }
+    }
+
+    //
+    // identifier must be of type constant, a global, or a temporary
+    //
+    TQualifier qualifier = variable->getType().getQualifier();
+    if ((qualifier != EvqTemporary) && (qualifier != EvqGlobal) && (qualifier != EvqConst)) {
+        error(line, " cannot initialize this type of qualifier ", variable->getType().getQualifierString());
+        return true;
+    }
+    //
+    // test for and propagate constant
+    //
+
+    if (qualifier == EvqConst) {
+        if (qualifier != initializer->getType().getQualifier()) {
+            std::stringstream extraInfoStream;
+            extraInfoStream << "'" << variable->getType().getCompleteString() << "'";
+            std::string extraInfo = extraInfoStream.str();
+            error(line, " assigning non-constant to", "=", extraInfo.c_str());
+            variable->getType().setQualifier(EvqTemporary);
+            return true;
+        }
+        if (type != initializer->getType()) {
+            error(line, " non-matching types for const initializer ", 
+                variable->getType().getQualifierString());
+            variable->getType().setQualifier(EvqTemporary);
+            return true;
+        }
+        if (initializer->getAsConstantUnion()) { 
+            ConstantUnion* unionArray = variable->getConstPointer();
+
+            if (type.getObjectSize() == 1 && type.getBasicType() != EbtStruct) {
+                *unionArray = (initializer->getAsConstantUnion()->getUnionArrayPointer())[0];
+            } else {
+                variable->shareConstPointer(initializer->getAsConstantUnion()->getUnionArrayPointer());
+            }
+        } else if (initializer->getAsSymbolNode()) {
+            const TSymbol* symbol = symbolTable.find(initializer->getAsSymbolNode()->getSymbol());
+            const TVariable* tVar = static_cast<const TVariable*>(symbol);
+
+            ConstantUnion* constArray = tVar->getConstPointer();
+            variable->shareConstPointer(constArray);
+        } else {
+            std::stringstream extraInfoStream;
+            extraInfoStream << "'" << variable->getType().getCompleteString() << "'";
+            std::string extraInfo = extraInfoStream.str();
+            error(line, " cannot assign to", "=", extraInfo.c_str());
+            variable->getType().setQualifier(EvqTemporary);
+            return true;
+        }
+    }
+ 
+    if (qualifier != EvqConst) {
+        TIntermSymbol* intermSymbol = intermediate.addSymbol(variable->getUniqueId(), variable->getName(), variable->getType(), line);
+        intermNode = intermediate.addAssign(EOpInitialize, intermSymbol, initializer, line);
+        if (intermNode == 0) {
+            assignError(line, "=", intermSymbol->getCompleteString(), initializer->getCompleteString());
+            return true;
+        }
+    } else 
+        intermNode = 0;
+
+    return false;
+}
+
+bool TParseContext::areAllChildConst(TIntermAggregate* aggrNode)
+{
+    ASSERT(aggrNode != NULL);
+    if (!aggrNode->isConstructor())
+        return false;
+
+    bool allConstant = true;
+
+    // check if all the child nodes are constants so that they can be inserted into 
+    // the parent node
+    TIntermSequence &sequence = aggrNode->getSequence() ;
+    for (TIntermSequence::iterator p = sequence.begin(); p != sequence.end(); ++p) {
+        if (!(*p)->getAsTyped()->getAsConstantUnion())
+            return false;
+    }
+
+    return allConstant;
+}
+
+// This function is used to test for the correctness of the parameters passed to various constructor functions
+// and also convert them to the right datatype if it is allowed and required. 
+//
+// Returns 0 for an error or the constructed node (aggregate or typed) for no error.
+//
+TIntermTyped* TParseContext::addConstructor(TIntermNode* node, const TType* type, TOperator op, TFunction* fnCall, TSourceLoc line)
+{
+    if (node == 0)
+        return 0;
+
+    TIntermAggregate* aggrNode = node->getAsAggregate();
+    
+    TTypeList::const_iterator memberTypes;
+    if (op == EOpConstructStruct)
+        memberTypes = type->getStruct()->begin();
+    
+    TType elementType = *type;
+    if (type->isArray())
+        elementType.clearArrayness();
+
+    bool singleArg;
+    if (aggrNode) {
+        if (aggrNode->getOp() != EOpNull || aggrNode->getSequence().size() == 1)
+            singleArg = true;
+        else
+            singleArg = false;
+    } else
+        singleArg = true;
+
+    TIntermTyped *newNode;
+    if (singleArg) {
+        // If structure constructor or array constructor is being called 
+        // for only one parameter inside the structure, we need to call constructStruct function once.
+        if (type->isArray())
+            newNode = constructStruct(node, &elementType, 1, node->getLine(), false);
+        else if (op == EOpConstructStruct)
+            newNode = constructStruct(node, (*memberTypes).type, 1, node->getLine(), false);
+        else
+            newNode = constructBuiltIn(type, op, node, node->getLine(), false);
+
+        if (newNode && newNode->getAsAggregate()) {
+            TIntermTyped* constConstructor = foldConstConstructor(newNode->getAsAggregate(), *type);
+            if (constConstructor)
+                return constConstructor;
+        }
+
+        return newNode;
+    }
+    
+    //
+    // Handle list of arguments.
+    //
+    TIntermSequence &sequenceVector = aggrNode->getSequence() ;    // Stores the information about the parameter to the constructor
+    // if the structure constructor contains more than one parameter, then construct
+    // each parameter
+    
+    int paramCount = 0;  // keeps a track of the constructor parameter number being checked    
+    
+    // for each parameter to the constructor call, check to see if the right type is passed or convert them 
+    // to the right type if possible (and allowed).
+    // for structure constructors, just check if the right type is passed, no conversion is allowed.
+    
+    for (TIntermSequence::iterator p = sequenceVector.begin(); 
+                                   p != sequenceVector.end(); p++, paramCount++) {
+        if (type->isArray())
+            newNode = constructStruct(*p, &elementType, paramCount+1, node->getLine(), true);
+        else if (op == EOpConstructStruct)
+            newNode = constructStruct(*p, (memberTypes[paramCount]).type, paramCount+1, node->getLine(), true);
+        else
+            newNode = constructBuiltIn(type, op, *p, node->getLine(), true);
+        
+        if (newNode) {
+            *p = newNode;
+        }
+    }
+
+    TIntermTyped* constructor = intermediate.setAggregateOperator(aggrNode, op, line);
+    TIntermTyped* constConstructor = foldConstConstructor(constructor->getAsAggregate(), *type);
+    if (constConstructor)
+        return constConstructor;
+
+    return constructor;
+}
+
+TIntermTyped* TParseContext::foldConstConstructor(TIntermAggregate* aggrNode, const TType& type)
+{
+    bool canBeFolded = areAllChildConst(aggrNode);
+    aggrNode->setType(type);
+    if (canBeFolded) {
+        bool returnVal = false;
+        ConstantUnion* unionArray = new ConstantUnion[type.getObjectSize()];
+        if (aggrNode->getSequence().size() == 1)  {
+            returnVal = intermediate.parseConstTree(aggrNode->getLine(), aggrNode, unionArray, aggrNode->getOp(), symbolTable,  type, true);
+        }
+        else {
+            returnVal = intermediate.parseConstTree(aggrNode->getLine(), aggrNode, unionArray, aggrNode->getOp(), symbolTable,  type);
+        }
+        if (returnVal)
+            return 0;
+
+        return intermediate.addConstantUnion(unionArray, type, aggrNode->getLine());
+    }
+
+    return 0;
+}
+
+// Function for constructor implementation. Calls addUnaryMath with appropriate EOp value
+// for the parameter to the constructor (passed to this function). Essentially, it converts
+// the parameter types correctly. If a constructor expects an int (like ivec2) and is passed a 
+// float, then float is converted to int.
+//
+// Returns 0 for an error or the constructed node.
+//
+TIntermTyped* TParseContext::constructBuiltIn(const TType* type, TOperator op, TIntermNode* node, TSourceLoc line, bool subset)
+{
+    TIntermTyped* newNode;
+    TOperator basicOp;
+
+    //
+    // First, convert types as needed.
+    //
+    switch (op) {
+    case EOpConstructVec2:
+    case EOpConstructVec3:
+    case EOpConstructVec4:
+    case EOpConstructMat2:
+    case EOpConstructMat3:
+    case EOpConstructMat4:
+    case EOpConstructFloat:
+        basicOp = EOpConstructFloat;
+        break;
+
+    case EOpConstructIVec2:
+    case EOpConstructIVec3:
+    case EOpConstructIVec4:
+    case EOpConstructInt:
+        basicOp = EOpConstructInt;
+        break;
+
+    case EOpConstructBVec2:
+    case EOpConstructBVec3:
+    case EOpConstructBVec4:
+    case EOpConstructBool:
+        basicOp = EOpConstructBool;
+        break;
+
+    default:
+        error(line, "unsupported construction", "");
+        recover();
+
+        return 0;
+    }
+    newNode = intermediate.addUnaryMath(basicOp, node, node->getLine(), symbolTable);
+    if (newNode == 0) {
+        error(line, "can't convert", "constructor");
+        return 0;
+    }
+
+    //
+    // Now, if there still isn't an operation to do the construction, and we need one, add one.
+    //
+    
+    // Otherwise, skip out early.
+    if (subset || (newNode != node && newNode->getType() == *type))
+        return newNode;
+
+    // setAggregateOperator will insert a new node for the constructor, as needed.
+    return intermediate.setAggregateOperator(newNode, op, line);
+}
+
+// This function tests for the type of the parameters to the structures constructors. Raises
+// an error message if the expected type does not match the parameter passed to the constructor.
+//
+// Returns 0 for an error or the input node itself if the expected and the given parameter types match.
+//
+TIntermTyped* TParseContext::constructStruct(TIntermNode* node, TType* type, int paramCount, TSourceLoc line, bool subset)
+{
+    if (*type == node->getAsTyped()->getType()) {
+        if (subset)
+            return node->getAsTyped();
+        else
+            return intermediate.setAggregateOperator(node->getAsTyped(), EOpConstructStruct, line);
+    } else {
+        std::stringstream extraInfoStream;
+        extraInfoStream << "cannot convert parameter " << paramCount 
+                        << " from '" << node->getAsTyped()->getType().getBasicString()
+                        << "' to '" << type->getBasicString() << "'";
+        std::string extraInfo = extraInfoStream.str();
+        error(line, "", "constructor", extraInfo.c_str());
+        recover();
+    }
+
+    return 0;
+}
+
+//
+// This function returns the tree representation for the vector field(s) being accessed from contant vector.
+// If only one component of vector is accessed (v.x or v[0] where v is a contant vector), then a contant node is
+// returned, else an aggregate node is returned (for v.xy). The input to this function could either be the symbol
+// node or it could be the intermediate tree representation of accessing fields in a constant structure or column of 
+// a constant matrix.
+//
+TIntermTyped* TParseContext::addConstVectorNode(TVectorFields& fields, TIntermTyped* node, TSourceLoc line)
+{
+    TIntermTyped* typedNode;
+    TIntermConstantUnion* tempConstantNode = node->getAsConstantUnion();
+
+    ConstantUnion *unionArray;
+    if (tempConstantNode) {
+        unionArray = tempConstantNode->getUnionArrayPointer();
+        ASSERT(unionArray);
+
+        if (!unionArray) {
+            return node;
+        }
+    } else { // The node has to be either a symbol node or an aggregate node or a tempConstant node, else, its an error
+        error(line, "Cannot offset into the vector", "Error");
+        recover();
+
+        return 0;
+    }
+
+    ConstantUnion* constArray = new ConstantUnion[fields.num];
+
+    for (int i = 0; i < fields.num; i++) {
+        if (fields.offsets[i] >= node->getType().getObjectSize()) {
+            std::stringstream extraInfoStream;
+            extraInfoStream << "vector field selection out of range '" << fields.offsets[i] << "'";
+            std::string extraInfo = extraInfoStream.str();
+            error(line, "", "[", extraInfo.c_str());
+            recover();
+            fields.offsets[i] = 0;
+        }
+        
+        constArray[i] = unionArray[fields.offsets[i]];
+
+    } 
+    typedNode = intermediate.addConstantUnion(constArray, node->getType(), line);
+    return typedNode;
+}
+
+//
+// This function returns the column being accessed from a constant matrix. The values are retrieved from
+// the symbol table and parse-tree is built for a vector (each column of a matrix is a vector). The input 
+// to the function could either be a symbol node (m[0] where m is a constant matrix)that represents a 
+// constant matrix or it could be the tree representation of the constant matrix (s.m1[0] where s is a constant structure)
+//
+TIntermTyped* TParseContext::addConstMatrixNode(int index, TIntermTyped* node, TSourceLoc line)
+{
+    TIntermTyped* typedNode;
+    TIntermConstantUnion* tempConstantNode = node->getAsConstantUnion();
+
+    if (index >= node->getType().getNominalSize()) {
+        std::stringstream extraInfoStream;
+        extraInfoStream << "matrix field selection out of range '" << index << "'";
+        std::string extraInfo = extraInfoStream.str();
+        error(line, "", "[", extraInfo.c_str());
+        recover();
+        index = 0;
+    }
+
+    if (tempConstantNode) {
+         ConstantUnion* unionArray = tempConstantNode->getUnionArrayPointer();
+         int size = tempConstantNode->getType().getNominalSize();
+         typedNode = intermediate.addConstantUnion(&unionArray[size*index], tempConstantNode->getType(), line);
+    } else {
+        error(line, "Cannot offset into the matrix", "Error");
+        recover();
+
+        return 0;
+    }
+
+    return typedNode;
+}
+
+
+//
+// This function returns an element of an array accessed from a constant array. The values are retrieved from
+// the symbol table and parse-tree is built for the type of the element. The input 
+// to the function could either be a symbol node (a[0] where a is a constant array)that represents a 
+// constant array or it could be the tree representation of the constant array (s.a1[0] where s is a constant structure)
+//
+TIntermTyped* TParseContext::addConstArrayNode(int index, TIntermTyped* node, TSourceLoc line)
+{
+    TIntermTyped* typedNode;
+    TIntermConstantUnion* tempConstantNode = node->getAsConstantUnion();
+    TType arrayElementType = node->getType();
+    arrayElementType.clearArrayness();
+
+    if (index >= node->getType().getArraySize()) {
+        std::stringstream extraInfoStream;
+        extraInfoStream << "array field selection out of range '" << index << "'";
+        std::string extraInfo = extraInfoStream.str();
+        error(line, "", "[", extraInfo.c_str());
+        recover();
+        index = 0;
+    }
+
+    int arrayElementSize = arrayElementType.getObjectSize();
+
+    if (tempConstantNode) {
+         ConstantUnion* unionArray = tempConstantNode->getUnionArrayPointer();
+         typedNode = intermediate.addConstantUnion(&unionArray[arrayElementSize * index], tempConstantNode->getType(), line);
+    } else {
+        error(line, "Cannot offset into the array", "Error");
+        recover();
+
+        return 0;
+    }
+
+    return typedNode;
+}
+
+
+//
+// This function returns the value of a particular field inside a constant structure from the symbol table. 
+// If there is an embedded/nested struct, it appropriately calls addConstStructNested or addConstStructFromAggr
+// function and returns the parse-tree with the values of the embedded/nested struct.
+//
+TIntermTyped* TParseContext::addConstStruct(TString& identifier, TIntermTyped* node, TSourceLoc line)
+{
+    const TTypeList* fields = node->getType().getStruct();
+    TIntermTyped *typedNode;
+    int instanceSize = 0;
+    unsigned int index = 0;
+    TIntermConstantUnion *tempConstantNode = node->getAsConstantUnion();
+
+    for ( index = 0; index < fields->size(); ++index) {
+        if ((*fields)[index].type->getFieldName() == identifier) {
+            break;
+        } else {
+            instanceSize += (*fields)[index].type->getObjectSize();
+        }
+    }
+
+    if (tempConstantNode) {
+         ConstantUnion* constArray = tempConstantNode->getUnionArrayPointer();
+
+         typedNode = intermediate.addConstantUnion(constArray+instanceSize, tempConstantNode->getType(), line); // type will be changed in the calling function
+    } else {
+        error(line, "Cannot offset into the structure", "Error");
+        recover();
+
+        return 0;
+    }
+
+    return typedNode;
+}
+
+bool TParseContext::enterStructDeclaration(int line, const TString& identifier)
+{
+    ++structNestingLevel;
+
+    // Embedded structure definitions are not supported per GLSL ES spec.
+    // They aren't allowed in GLSL either, but we need to detect this here
+    // so we don't rely on the GLSL compiler to catch it.
+    if (structNestingLevel > 1) {
+        error(line, "", "Embedded struct definitions are not allowed");
+        return true;
+    }
+
+    return false;
+}
+
+void TParseContext::exitStructDeclaration()
+{
+    --structNestingLevel;
+}
+
+namespace {
+
+const int kWebGLMaxStructNesting = 4;
+
+}  // namespace
+
+bool TParseContext::structNestingErrorCheck(TSourceLoc line, const TType& fieldType)
+{
+    if (shaderSpec != SH_WEBGL_SPEC) {
+        return false;
+    }
+
+    if (fieldType.getBasicType() != EbtStruct) {
+        return false;
+    }
+
+    // We're already inside a structure definition at this point, so add
+    // one to the field's struct nesting.
+    if (1 + fieldType.getDeepestStructNesting() > kWebGLMaxStructNesting) {
+        std::stringstream extraInfoStream;
+        extraInfoStream << "Reference of struct type " << fieldType.getTypeName() 
+                        << " exceeds maximum struct nesting of " << kWebGLMaxStructNesting;
+        std::string extraInfo = extraInfoStream.str();
+        error(line, "", "", extraInfo.c_str());
+        return true;
+    }
+
+    return false;
+}
+
+//
+// Parse an array of strings using yyparse.
+//
+// Returns 0 for success.
+//
+int PaParseStrings(int count, const char* const string[], const int length[],
+                   TParseContext* context) {
+    if ((count == 0) || (string == NULL))
+        return 1;
+
+    if (glslang_initialize(context))
+        return 1;
+
+    int error = glslang_scan(count, string, length, context);
+    if (!error)
+        error = glslang_parse(context);
+
+    glslang_finalize(context);
+
+    return (error == 0) && (context->numErrors() == 0) ? 0 : 1;
+}
+
+
+