ASTBuilder.h   [plain text]

/*
 * Copyright (C) 2010, 2013 Apple Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS''
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
 * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF
 * THE POSSIBILITY OF SUCH DAMAGE.
 */

#ifndef ASTBuilder_h
#define ASTBuilder_h

#include "BuiltinNames.h"
#include "BytecodeIntrinsicRegistry.h"
#include "NodeConstructors.h"
#include "SyntaxChecker.h"
#include <utility>

namespace JSC {

class ASTBuilder {
    struct BinaryOpInfo {
        BinaryOpInfo() {}
        BinaryOpInfo(const JSTextPosition& otherStart, const JSTextPosition& otherDivot, const JSTextPosition& otherEnd, bool rhsHasAssignment)
            : start(otherStart)
            , divot(otherDivot)
            , end(otherEnd)
            , hasAssignment(rhsHasAssignment)
        {
        }
        BinaryOpInfo(const BinaryOpInfo& lhs, const BinaryOpInfo& rhs)
            : start(lhs.start)
            , divot(rhs.start)
            , end(rhs.end)
            , hasAssignment(lhs.hasAssignment || rhs.hasAssignment)
        {
        }
        JSTextPosition start;
        JSTextPosition divot;
        JSTextPosition end;
        bool hasAssignment;
    };
    
    
    struct AssignmentInfo {
        AssignmentInfo() {}
        AssignmentInfo(ExpressionNode* node, const JSTextPosition& start, const JSTextPosition& divot, int initAssignments, Operator op)
            : m_node(node)
            , m_start(start)
            , m_divot(divot)
            , m_initAssignments(initAssignments)
            , m_op(op)
        {
            ASSERT(m_divot.offset >= m_divot.lineStartOffset);
            ASSERT(m_start.offset >= m_start.lineStartOffset);
        }
        ExpressionNode* m_node;
        JSTextPosition m_start;
        JSTextPosition m_divot;
        int m_initAssignments;
        Operator m_op;
    };
public:
    ASTBuilder(VM* vm, ParserArena& parserArena, SourceCode* sourceCode)
        : m_vm(vm)
        , m_parserArena(parserArena)
        , m_sourceCode(sourceCode)
        , m_evalCount(0)
    {
    }
    
    struct BinaryExprContext {
        BinaryExprContext(ASTBuilder&) {}
    };
    struct UnaryExprContext {
        UnaryExprContext(ASTBuilder&) {}
    };


    typedef SyntaxChecker FunctionBodyBuilder;

    typedef ExpressionNode* Expression;
    typedef JSC::SourceElements* SourceElements;
    typedef ArgumentsNode* Arguments;
    typedef CommaNode* Comma;
    typedef PropertyNode* Property;
    typedef PropertyListNode* PropertyList;
    typedef ElementNode* ElementList;
    typedef ArgumentListNode* ArgumentsList;
#if ENABLE(ES6_TEMPLATE_LITERAL_SYNTAX)
    typedef TemplateExpressionListNode* TemplateExpressionList;
    typedef TemplateStringNode* TemplateString;
    typedef TemplateStringListNode* TemplateStringList;
    typedef TemplateLiteralNode* TemplateLiteral;
#endif
    typedef ParameterNode* FormalParameterList;
    typedef FunctionBodyNode* FunctionBody;
#if ENABLE(ES6_CLASS_SYNTAX)
    typedef ClassExprNode* ClassExpression;
#endif
    typedef StatementNode* Statement;
    typedef ClauseListNode* ClauseList;
    typedef CaseClauseNode* Clause;
    typedef ConstDeclNode* ConstDeclList;
    typedef std::pair<ExpressionNode*, BinaryOpInfo> BinaryOperand;
    typedef RefPtr<DestructuringPatternNode> DestructuringPattern;
    typedef RefPtr<ArrayPatternNode> ArrayPattern;
    typedef RefPtr<ObjectPatternNode> ObjectPattern;
    typedef RefPtr<BindingNode> BindingPattern;
    static const bool CreatesAST = true;
    static const bool NeedsFreeVariableInfo = true;
    static const bool CanUseFunctionCache = true;
    static const int  DontBuildKeywords = 0;
    static const int  DontBuildStrings = 0;

    ExpressionNode* makeBinaryNode(const JSTokenLocation&, int token, std::pair<ExpressionNode*, BinaryOpInfo>, std::pair<ExpressionNode*, BinaryOpInfo>);
    ExpressionNode* makeFunctionCallNode(const JSTokenLocation&, ExpressionNode* func, ArgumentsNode* args, const JSTextPosition& divotStart, const JSTextPosition& divot, const JSTextPosition& divotEnd);

    JSC::SourceElements* createSourceElements() { return new (m_parserArena) JSC::SourceElements(); }

    DeclarationStacks::VarStack& varDeclarations() { return m_scope.m_varDeclarations; }
    DeclarationStacks::FunctionStack& funcDeclarations() { return m_scope.m_funcDeclarations; }
    int features() const { return m_scope.m_features; }
    int numConstants() const { return m_scope.m_numConstants; }

    ExpressionNode* makeAssignNode(const JSTokenLocation&, ExpressionNode* left, Operator, ExpressionNode* right, bool leftHasAssignments, bool rightHasAssignments, const JSTextPosition& start, const JSTextPosition& divot, const JSTextPosition& end);
    ExpressionNode* makePrefixNode(const JSTokenLocation&, ExpressionNode*, Operator, const JSTextPosition& start, const JSTextPosition& divot, const JSTextPosition& end);
    ExpressionNode* makePostfixNode(const JSTokenLocation&, ExpressionNode*, Operator, const JSTextPosition& start, const JSTextPosition& divot, const JSTextPosition& end);
    ExpressionNode* makeTypeOfNode(const JSTokenLocation&, ExpressionNode*);
    ExpressionNode* makeDeleteNode(const JSTokenLocation&, ExpressionNode*, const JSTextPosition& start, const JSTextPosition& divot, const JSTextPosition& end);
    ExpressionNode* makeNegateNode(const JSTokenLocation&, ExpressionNode*);
    ExpressionNode* makeBitwiseNotNode(const JSTokenLocation&, ExpressionNode*);
    ExpressionNode* makeMultNode(const JSTokenLocation&, ExpressionNode* left, ExpressionNode* right, bool rightHasAssignments);
    ExpressionNode* makeDivNode(const JSTokenLocation&, ExpressionNode* left, ExpressionNode* right, bool rightHasAssignments);
    ExpressionNode* makeModNode(const JSTokenLocation&, ExpressionNode* left, ExpressionNode* right, bool rightHasAssignments);
    ExpressionNode* makeAddNode(const JSTokenLocation&, ExpressionNode* left, ExpressionNode* right, bool rightHasAssignments);
    ExpressionNode* makeSubNode(const JSTokenLocation&, ExpressionNode* left, ExpressionNode* right, bool rightHasAssignments);
    ExpressionNode* makeBitXOrNode(const JSTokenLocation&, ExpressionNode* left, ExpressionNode* right, bool rightHasAssignments);
    ExpressionNode* makeBitAndNode(const JSTokenLocation&, ExpressionNode* left, ExpressionNode* right, bool rightHasAssignments);
    ExpressionNode* makeBitOrNode(const JSTokenLocation&, ExpressionNode* left, ExpressionNode* right, bool rightHasAssignments);
    ExpressionNode* makeLeftShiftNode(const JSTokenLocation&, ExpressionNode* left, ExpressionNode* right, bool rightHasAssignments);
    ExpressionNode* makeRightShiftNode(const JSTokenLocation&, ExpressionNode* left, ExpressionNode* right, bool rightHasAssignments);
    ExpressionNode* makeURightShiftNode(const JSTokenLocation&, ExpressionNode* left, ExpressionNode* right, bool rightHasAssignments);

    ExpressionNode* createLogicalNot(const JSTokenLocation& location, ExpressionNode* expr)
    {
        if (expr->isNumber())
            return createBoolean(location, isZeroOrUnordered(static_cast<NumberNode*>(expr)->value()));

        return new (m_parserArena) LogicalNotNode(location, expr);
    }
    ExpressionNode* createUnaryPlus(const JSTokenLocation& location, ExpressionNode* expr) { return new (m_parserArena) UnaryPlusNode(location, expr); }
    ExpressionNode* createVoid(const JSTokenLocation& location, ExpressionNode* expr)
    {
        incConstants();
        return new (m_parserArena) VoidNode(location, expr);
    }
    ExpressionNode* thisExpr(const JSTokenLocation& location, ThisTDZMode thisTDZMode)
    {
        usesThis();
        return new (m_parserArena) ThisNode(location, thisTDZMode);
    }
    ExpressionNode* superExpr(const JSTokenLocation& location)
    {
        return new (m_parserArena) SuperNode(location);
    }
    ExpressionNode* createResolve(const JSTokenLocation& location, const Identifier* ident, const JSTextPosition& start)
    {
        if (m_vm->propertyNames->arguments == *ident)
            usesArguments();
        return new (m_parserArena) ResolveNode(location, *ident, start);
    }
    ExpressionNode* createObjectLiteral(const JSTokenLocation& location) { return new (m_parserArena) ObjectLiteralNode(location); }
    ExpressionNode* createObjectLiteral(const JSTokenLocation& location, PropertyListNode* properties) { return new (m_parserArena) ObjectLiteralNode(location, properties); }

    ExpressionNode* createArray(const JSTokenLocation& location, int elisions)
    {
        if (elisions)
            incConstants();
        return new (m_parserArena) ArrayNode(location, elisions);
    }

    ExpressionNode* createArray(const JSTokenLocation& location, ElementNode* elems) { return new (m_parserArena) ArrayNode(location, elems); }
    ExpressionNode* createArray(const JSTokenLocation& location, int elisions, ElementNode* elems)
    {
        if (elisions)
            incConstants();
        return new (m_parserArena) ArrayNode(location, elisions, elems);
    }
    ExpressionNode* createDoubleExpr(const JSTokenLocation& location, double d)
    {
        incConstants();
        return new (m_parserArena) DoubleNode(location, d);
    }
    ExpressionNode* createIntegerExpr(const JSTokenLocation& location, double d)
    {
        incConstants();
        return new (m_parserArena) IntegerNode(location, d);
    }

    ExpressionNode* createString(const JSTokenLocation& location, const Identifier* string)
    {
        incConstants();
        return new (m_parserArena) StringNode(location, *string);
    }

    ExpressionNode* createBoolean(const JSTokenLocation& location, bool b)
    {
        incConstants();
        return new (m_parserArena) BooleanNode(location, b);
    }

    ExpressionNode* createNull(const JSTokenLocation& location)
    {
        incConstants();
        return new (m_parserArena) NullNode(location);
    }

    ExpressionNode* createBracketAccess(const JSTokenLocation& location, ExpressionNode* base, ExpressionNode* property, bool propertyHasAssignments, const JSTextPosition& start, const JSTextPosition& divot, const JSTextPosition& end)
    {
        BracketAccessorNode* node = new (m_parserArena) BracketAccessorNode(location, base, property, propertyHasAssignments);
        setExceptionLocation(node, start, divot, end);
        return node;
    }

    ExpressionNode* createDotAccess(const JSTokenLocation& location, ExpressionNode* base, const Identifier* property, const JSTextPosition& start, const JSTextPosition& divot, const JSTextPosition& end)
    {
        DotAccessorNode* node = new (m_parserArena) DotAccessorNode(location, base, *property);
        setExceptionLocation(node, start, divot, end);
        return node;
    }

    ExpressionNode* createSpreadExpression(const JSTokenLocation& location, ExpressionNode* expression, const JSTextPosition& start, const JSTextPosition& divot, const JSTextPosition& end)
    {
        auto node = new (m_parserArena) SpreadExpressionNode(location, expression);
        setExceptionLocation(node, start, divot, end);
        return node;
    }

#if ENABLE(ES6_TEMPLATE_LITERAL_SYNTAX)
    TemplateStringNode* createTemplateString(const JSTokenLocation& location, const Identifier& cooked, const Identifier& raw)
    {
        return new (m_parserArena) TemplateStringNode(location, cooked, raw);
    }

    TemplateStringListNode* createTemplateStringList(TemplateStringNode* templateString)
    {
        return new (m_parserArena) TemplateStringListNode(templateString);
    }

    TemplateStringListNode* createTemplateStringList(TemplateStringListNode* templateStringList, TemplateStringNode* templateString)
    {
        return new (m_parserArena) TemplateStringListNode(templateStringList, templateString);
    }

    TemplateExpressionListNode* createTemplateExpressionList(ExpressionNode* expression)
    {
        return new (m_parserArena) TemplateExpressionListNode(expression);
    }

    TemplateExpressionListNode* createTemplateExpressionList(TemplateExpressionListNode* templateExpressionListNode, ExpressionNode* expression)
    {
        return new (m_parserArena) TemplateExpressionListNode(templateExpressionListNode, expression);
    }

    TemplateLiteralNode* createTemplateLiteral(const JSTokenLocation& location, TemplateStringListNode* templateStringList)
    {
        return new (m_parserArena) TemplateLiteralNode(location, templateStringList);
    }

    TemplateLiteralNode* createTemplateLiteral(const JSTokenLocation& location, TemplateStringListNode* templateStringList, TemplateExpressionListNode* templateExpressionList)
    {
        return new (m_parserArena) TemplateLiteralNode(location, templateStringList, templateExpressionList);
    }

    ExpressionNode* createTaggedTemplate(const JSTokenLocation& location, ExpressionNode* base, TemplateLiteralNode* templateLiteral, const JSTextPosition& start, const JSTextPosition& divot, const JSTextPosition& end)
    {
        auto node = new (m_parserArena) TaggedTemplateNode(location, base, templateLiteral);
        setExceptionLocation(node, start, divot, end);
        return node;
    }
#endif

    ExpressionNode* createRegExp(const JSTokenLocation& location, const Identifier& pattern, const Identifier& flags, const JSTextPosition& start)
    {
        if (Yarr::checkSyntax(pattern.string()))
            return 0;
        RegExpNode* node = new (m_parserArena) RegExpNode(location, pattern, flags);
        int size = pattern.length() + 2; // + 2 for the two /'s
        JSTextPosition end = start + size;
        setExceptionLocation(node, start, end, end);
        return node;
    }

    ExpressionNode* createNewExpr(const JSTokenLocation& location, ExpressionNode* expr, ArgumentsNode* arguments, const JSTextPosition& start, const JSTextPosition& divot, const JSTextPosition& end)
    {
        NewExprNode* node = new (m_parserArena) NewExprNode(location, expr, arguments);
        setExceptionLocation(node, start, divot, end);
        return node;
    }

    ExpressionNode* createNewExpr(const JSTokenLocation& location, ExpressionNode* expr, const JSTextPosition& start, const JSTextPosition& end)
    {
        NewExprNode* node = new (m_parserArena) NewExprNode(location, expr);
        setExceptionLocation(node, start, end, end);
        return node;
    }

    ExpressionNode* createConditionalExpr(const JSTokenLocation& location, ExpressionNode* condition, ExpressionNode* lhs, ExpressionNode* rhs)
    {
        return new (m_parserArena) ConditionalNode(location, condition, lhs, rhs);
    }

    ExpressionNode* createAssignResolve(const JSTokenLocation& location, const Identifier& ident, ExpressionNode* rhs, const JSTextPosition& start, const JSTextPosition& divot, const JSTextPosition& end)
    {
        if (rhs->isFuncExprNode())
            static_cast<FuncExprNode*>(rhs)->body()->setInferredName(ident);
        AssignResolveNode* node = new (m_parserArena) AssignResolveNode(location, ident, rhs);
        setExceptionLocation(node, start, divot, end);
        return node;
    }

#if ENABLE(ES6_CLASS_SYNTAX)
    ClassExprNode* createClassExpr(const JSTokenLocation& location, const Identifier& name, ExpressionNode* constructor,
        ExpressionNode* parentClass, PropertyListNode* instanceMethods, PropertyListNode* staticMethods)
    {
        return new (m_parserArena) ClassExprNode(location, name, constructor, parentClass, instanceMethods, staticMethods);
    }
#endif

    ExpressionNode* createFunctionExpr(const JSTokenLocation& location, const ParserFunctionInfo<ASTBuilder>& info)
    {
        FuncExprNode* result = new (m_parserArena) FuncExprNode(location, *info.name, info.body,
            m_sourceCode->subExpression(info.startFunctionOffset, info.endFunctionOffset, info.bodyStartLine, info.bodyStartColumn), info.parameters);
        info.body->setLoc(info.bodyStartLine, info.bodyEndLine, location.startOffset, location.lineStartOffset);
        return result;
    }

    FunctionBodyNode* createFunctionBody(
        const JSTokenLocation& startLocation, const JSTokenLocation& endLocation, 
        unsigned startColumn, unsigned endColumn, int functionKeywordStart, 
        int functionNameStart, int parametersStart, bool inStrictContext, 
        ConstructorKind constructorKind)
    {
        return new (m_parserArena) FunctionBodyNode(
            m_parserArena, startLocation, endLocation, startColumn, endColumn, 
            functionKeywordStart, functionNameStart, parametersStart, 
            inStrictContext, constructorKind);
    }

#if ENABLE(ES6_ARROWFUNCTION_SYNTAX)
    ExpressionNode* createArrowFunctionExpr(const JSTokenLocation& location, const ParserFunctionInfo<ASTBuilder>& info)
    {
        SourceCode source = info.functionBodyType == ArrowFunctionBodyExpression
            ? m_sourceCode->subArrowExpression(info.arrowFunctionOffset, info.endFunctionOffset, info.bodyStartLine, info.bodyStartColumn)
            : m_sourceCode->subExpression(info.startFunctionOffset, info.endFunctionOffset, info.bodyStartLine, info.bodyStartColumn);

        FuncExprNode* result = new (m_parserArena) FuncExprNode(location, *info.name, info.body, source, info.parameters);
        info.body->setLoc(info.bodyStartLine, info.bodyEndLine, location.startOffset, location.lineStartOffset);
        return result;
    }
#endif

    NEVER_INLINE PropertyNode* createGetterOrSetterProperty(const JSTokenLocation& location, PropertyNode::Type type, bool,
        const Identifier* name, const ParserFunctionInfo<ASTBuilder>& info, SuperBinding superBinding)
    {
        ASSERT(name);
        info.body->setLoc(info.bodyStartLine, info.bodyEndLine, location.startOffset, location.lineStartOffset);
        info.body->setInferredName(*name);
        SourceCode source = m_sourceCode->subExpression(info.startFunctionOffset, info.endFunctionOffset, info.bodyStartLine, info.bodyStartColumn);
        FuncExprNode* funcExpr = new (m_parserArena) FuncExprNode(location, m_vm->propertyNames->nullIdentifier, info.body, source, info.parameters);
        return new (m_parserArena) PropertyNode(*name, funcExpr, type, PropertyNode::Unknown, superBinding);
    }
    
    NEVER_INLINE PropertyNode* createGetterOrSetterProperty(VM* vm, ParserArena& parserArena, const JSTokenLocation& location, PropertyNode::Type type, bool,
        double name, const ParserFunctionInfo<ASTBuilder>& info, SuperBinding superBinding)
    {
        info.body->setLoc(info.bodyStartLine, info.bodyEndLine, location.startOffset, location.lineStartOffset);
        const Identifier& ident = parserArena.identifierArena().makeNumericIdentifier(vm, name);
        SourceCode source = m_sourceCode->subExpression(info.startFunctionOffset, info.endFunctionOffset, info.bodyStartLine, info.bodyStartColumn);
        FuncExprNode* funcExpr = new (m_parserArena) FuncExprNode(location, vm->propertyNames->nullIdentifier, info.body, source, info.parameters);
        return new (m_parserArena) PropertyNode(ident, funcExpr, type, PropertyNode::Unknown, superBinding);
    }

    ArgumentsNode* createArguments() { return new (m_parserArena) ArgumentsNode(); }
    ArgumentsNode* createArguments(ArgumentListNode* args) { return new (m_parserArena) ArgumentsNode(args); }
    ArgumentListNode* createArgumentsList(const JSTokenLocation& location, ExpressionNode* arg) { return new (m_parserArena) ArgumentListNode(location, arg); }
    ArgumentListNode* createArgumentsList(const JSTokenLocation& location, ArgumentListNode* args, ExpressionNode* arg) { return new (m_parserArena) ArgumentListNode(location, args, arg); }

    PropertyNode* createProperty(const Identifier* propertyName, ExpressionNode* node, PropertyNode::Type type, PropertyNode::PutType putType, bool, SuperBinding superBinding = SuperBinding::NotNeeded)
    {
        if (node->isFuncExprNode())
            static_cast<FuncExprNode*>(node)->body()->setInferredName(*propertyName);
        return new (m_parserArena) PropertyNode(*propertyName, node, type, putType, superBinding);
    }
    PropertyNode* createProperty(VM* vm, ParserArena& parserArena, double propertyName, ExpressionNode* node, PropertyNode::Type type, PropertyNode::PutType putType, bool)
    {
        return new (m_parserArena) PropertyNode(parserArena.identifierArena().makeNumericIdentifier(vm, propertyName), node, type, putType);
    }
    PropertyNode* createProperty(ExpressionNode* propertyName, ExpressionNode* node, PropertyNode::Type type, PropertyNode::PutType putType, bool) { return new (m_parserArena) PropertyNode(propertyName, node, type, putType); }
    PropertyListNode* createPropertyList(const JSTokenLocation& location, PropertyNode* property) { return new (m_parserArena) PropertyListNode(location, property); }
    PropertyListNode* createPropertyList(const JSTokenLocation& location, PropertyNode* property, PropertyListNode* tail) { return new (m_parserArena) PropertyListNode(location, property, tail); }

    ElementNode* createElementList(int elisions, ExpressionNode* expr) { return new (m_parserArena) ElementNode(elisions, expr); }
    ElementNode* createElementList(ElementNode* elems, int elisions, ExpressionNode* expr) { return new (m_parserArena) ElementNode(elems, elisions, expr); }

    ParameterNode* createFormalParameterList(DestructuringPattern pattern) { return new (m_parserArena) ParameterNode(pattern); }
    ParameterNode* createFormalParameterList(ParameterNode* list, DestructuringPattern pattern) { return new (m_parserArena) ParameterNode(list, pattern); }

    CaseClauseNode* createClause(ExpressionNode* expr, JSC::SourceElements* statements) { return new (m_parserArena) CaseClauseNode(expr, statements); }
    ClauseListNode* createClauseList(CaseClauseNode* clause) { return new (m_parserArena) ClauseListNode(clause); }
    ClauseListNode* createClauseList(ClauseListNode* tail, CaseClauseNode* clause) { return new (m_parserArena) ClauseListNode(tail, clause); }

    StatementNode* createFuncDeclStatement(const JSTokenLocation& location, const ParserFunctionInfo<ASTBuilder>& info)
    {
        FuncDeclNode* decl = new (m_parserArena) FuncDeclNode(location, *info.name, info.body,
            m_sourceCode->subExpression(info.startFunctionOffset, info.endFunctionOffset, info.bodyStartLine, info.bodyStartColumn), info.parameters);
        if (*info.name == m_vm->propertyNames->arguments)
            usesArguments();
        m_scope.m_funcDeclarations.append(decl->body());
        info.body->setLoc(info.bodyStartLine, info.bodyEndLine, location.startOffset, location.lineStartOffset);
        return decl;
    }

#if ENABLE(ES6_CLASS_SYNTAX)
    StatementNode* createClassDeclStatement(const JSTokenLocation& location, ClassExprNode* classExpression,
        const JSTextPosition& classStart, const JSTextPosition& classEnd, unsigned startLine, unsigned endLine)
    {
        // FIXME: Use "let" declaration.
        ExpressionNode* assign = createAssignResolve(location, classExpression->name(), classExpression, classStart, classStart + 1, classEnd);
        ClassDeclNode* decl = new (m_parserArena) ClassDeclNode(location, assign);
        decl->setLoc(startLine, endLine, location.startOffset, location.lineStartOffset);
        return decl;
    }
#endif

    StatementNode* createBlockStatement(const JSTokenLocation& location, JSC::SourceElements* elements, int startLine, int endLine)
    {
        BlockNode* block = new (m_parserArena) BlockNode(location, elements);
        block->setLoc(startLine, endLine, location.startOffset, location.lineStartOffset);
        return block;
    }

    StatementNode* createExprStatement(const JSTokenLocation& location, ExpressionNode* expr, const JSTextPosition& start, int end)
    {
        ExprStatementNode* result = new (m_parserArena) ExprStatementNode(location, expr);
        result->setLoc(start.line, end, start.offset, start.lineStartOffset);
        return result;
    }

    StatementNode* createIfStatement(const JSTokenLocation& location, ExpressionNode* condition, StatementNode* trueBlock, StatementNode* falseBlock, int start, int end)
    {
        IfElseNode* result = new (m_parserArena) IfElseNode(location, condition, trueBlock, falseBlock);
        result->setLoc(start, end, location.startOffset, location.lineStartOffset);
        return result;
    }

    StatementNode* createForLoop(const JSTokenLocation& location, ExpressionNode* initializer, ExpressionNode* condition, ExpressionNode* iter, StatementNode* statements, int start, int end)
    {
        ForNode* result = new (m_parserArena) ForNode(location, initializer, condition, iter, statements);
        result->setLoc(start, end, location.startOffset, location.lineStartOffset);
        return result;
    }

    StatementNode* createForInLoop(const JSTokenLocation& location, ExpressionNode* lhs, ExpressionNode* iter, StatementNode* statements, const JSTextPosition& eStart, const JSTextPosition& eDivot, const JSTextPosition& eEnd, int start, int end)
    {
        ForInNode* result = new (m_parserArena) ForInNode(location, lhs, iter, statements);
        result->setLoc(start, end, location.startOffset, location.lineStartOffset);
        setExceptionLocation(result, eStart, eDivot, eEnd);
        return result;
    }
    
    StatementNode* createForInLoop(const JSTokenLocation& location, PassRefPtr<DestructuringPatternNode> pattern, ExpressionNode* iter, StatementNode* statements, const JSTextPosition& eStart, const JSTextPosition& eDivot, const JSTextPosition& eEnd, int start, int end)
    {
        auto lexpr = new (m_parserArena) DestructuringAssignmentNode(location, pattern.get(), 0);
        return createForInLoop(location, lexpr, iter, statements, eStart, eDivot, eEnd, start, end);
    }
    
    StatementNode* createForOfLoop(const JSTokenLocation& location, ExpressionNode* lhs, ExpressionNode* iter, StatementNode* statements, const JSTextPosition& eStart, const JSTextPosition& eDivot, const JSTextPosition& eEnd, int start, int end)
    {
        ForOfNode* result = new (m_parserArena) ForOfNode(location, lhs, iter, statements);
        result->setLoc(start, end, location.startOffset, location.lineStartOffset);
        setExceptionLocation(result, eStart, eDivot, eEnd);
        return result;
    }
    
    StatementNode* createForOfLoop(const JSTokenLocation& location, PassRefPtr<DestructuringPatternNode> pattern, ExpressionNode* iter, StatementNode* statements, const JSTextPosition& eStart, const JSTextPosition& eDivot, const JSTextPosition& eEnd, int start, int end)
    {
        auto lexpr = new (m_parserArena) DestructuringAssignmentNode(location, pattern.get(), 0);
        return createForOfLoop(location, lexpr, iter, statements, eStart, eDivot, eEnd, start, end);
    }

    bool isBindingNode(const DestructuringPattern& pattern)
    {
        return pattern->isBindingNode();
    }

    StatementNode* createEmptyStatement(const JSTokenLocation& location) { return new (m_parserArena) EmptyStatementNode(location); }

    StatementNode* createVarStatement(const JSTokenLocation& location, ExpressionNode* expr, int start, int end)
    {
        StatementNode* result;
        result = new (m_parserArena) VarStatementNode(location, expr);
        result->setLoc(start, end, location.startOffset, location.lineStartOffset);
        return result;
    }

    ExpressionNode* createEmptyVarExpression(const JSTokenLocation& location, const Identifier& identifier)
    {
        return new (m_parserArena) EmptyVarExpression(location, identifier);
    }

    StatementNode* createReturnStatement(const JSTokenLocation& location, ExpressionNode* expression, const JSTextPosition& start, const JSTextPosition& end)
    {
        ReturnNode* result = new (m_parserArena) ReturnNode(location, expression);
        setExceptionLocation(result, start, end, end);
        result->setLoc(start.line, end.line, start.offset, start.lineStartOffset);
        return result;
    }

    StatementNode* createBreakStatement(const JSTokenLocation& location, const Identifier* ident, const JSTextPosition& start, const JSTextPosition& end)
    {
        BreakNode* result = new (m_parserArena) BreakNode(location, *ident);
        setExceptionLocation(result, start, end, end);
        result->setLoc(start.line, end.line, start.offset, start.lineStartOffset);
        return result;
    }

    StatementNode* createContinueStatement(const JSTokenLocation& location, const Identifier* ident, const JSTextPosition& start, const JSTextPosition& end)
    {
        ContinueNode* result = new (m_parserArena) ContinueNode(location, *ident);
        setExceptionLocation(result, start, end, end);
        result->setLoc(start.line, end.line, start.offset, start.lineStartOffset);
        return result;
    }

    StatementNode* createTryStatement(const JSTokenLocation& location, StatementNode* tryBlock, const Identifier* ident, StatementNode* catchBlock, StatementNode* finallyBlock, int startLine, int endLine)
    {
        TryNode* result = new (m_parserArena) TryNode(location, tryBlock, *ident, catchBlock, finallyBlock);
        if (catchBlock)
            usesCatch();
        result->setLoc(startLine, endLine, location.startOffset, location.lineStartOffset);
        return result;
    }

    StatementNode* createSwitchStatement(const JSTokenLocation& location, ExpressionNode* expr, ClauseListNode* firstClauses, CaseClauseNode* defaultClause, ClauseListNode* secondClauses, int startLine, int endLine)
    {
        CaseBlockNode* cases = new (m_parserArena) CaseBlockNode(firstClauses, defaultClause, secondClauses);
        SwitchNode* result = new (m_parserArena) SwitchNode(location, expr, cases);
        result->setLoc(startLine, endLine, location.startOffset, location.lineStartOffset);
        return result;
    }

    StatementNode* createWhileStatement(const JSTokenLocation& location, ExpressionNode* expr, StatementNode* statement, int startLine, int endLine)
    {
        WhileNode* result = new (m_parserArena) WhileNode(location, expr, statement);
        result->setLoc(startLine, endLine, location.startOffset, location.lineStartOffset);
        return result;
    }

    StatementNode* createDoWhileStatement(const JSTokenLocation& location, StatementNode* statement, ExpressionNode* expr, int startLine, int endLine)
    {
        DoWhileNode* result = new (m_parserArena) DoWhileNode(location, statement, expr);
        result->setLoc(startLine, endLine, location.startOffset, location.lineStartOffset);
        return result;
    }

    StatementNode* createLabelStatement(const JSTokenLocation& location, const Identifier* ident, StatementNode* statement, const JSTextPosition& start, const JSTextPosition& end)
    {
        LabelNode* result = new (m_parserArena) LabelNode(location, *ident, statement);
        setExceptionLocation(result, start, end, end);
        return result;
    }

    StatementNode* createWithStatement(const JSTokenLocation& location, ExpressionNode* expr, StatementNode* statement, unsigned start, const JSTextPosition& end, unsigned startLine, unsigned endLine)
    {
        usesWith();
        WithNode* result = new (m_parserArena) WithNode(location, expr, statement, end, end - start);
        result->setLoc(startLine, endLine, location.startOffset, location.lineStartOffset);
        return result;
    }    
    
    StatementNode* createThrowStatement(const JSTokenLocation& location, ExpressionNode* expr, const JSTextPosition& start, const JSTextPosition& end)
    {
        ThrowNode* result = new (m_parserArena) ThrowNode(location, expr);
        result->setLoc(start.line, end.line, start.offset, start.lineStartOffset);
        setExceptionLocation(result, start, end, end);
        return result;
    }
    
    StatementNode* createDebugger(const JSTokenLocation& location, int startLine, int endLine)
    {
        DebuggerStatementNode* result = new (m_parserArena) DebuggerStatementNode(location);
        result->setLoc(startLine, endLine, location.startOffset, location.lineStartOffset);
        return result;
    }
    
    StatementNode* createConstStatement(const JSTokenLocation& location, ConstDeclNode* decls, int startLine, int endLine)
    {
        ConstStatementNode* result = new (m_parserArena) ConstStatementNode(location, decls);
        result->setLoc(startLine, endLine, location.startOffset, location.lineStartOffset);
        return result;
    }

    ConstDeclNode* appendConstDecl(const JSTokenLocation& location, ConstDeclNode* tail, const Identifier* name, ExpressionNode* initializer)
    {
        ConstDeclNode* result = new (m_parserArena) ConstDeclNode(location, *name, initializer);
        if (tail)
            tail->m_next = result;
        return result;
    }

    void appendStatement(JSC::SourceElements* elements, JSC::StatementNode* statement)
    {
        elements->append(statement);
    }

    void addVar(const Identifier* ident, int attrs)
    {
        if (m_vm->propertyNames->arguments == *ident)
            usesArguments();
        ASSERT(ident->impl()->isAtomic() || ident->impl()->isSymbol());
        m_scope.m_varDeclarations.append(std::make_pair(*ident, attrs));
    }

    CommaNode* createCommaExpr(const JSTokenLocation& location, ExpressionNode* node)
    {
        return new (m_parserArena) CommaNode(location, node);
    }

    CommaNode* appendToCommaExpr(const JSTokenLocation& location, ExpressionNode*, ExpressionNode* tail, ExpressionNode* next)
    {
        ASSERT(tail->isCommaNode());
        CommaNode* newTail = new (m_parserArena) CommaNode(location, next);
        static_cast<CommaNode*>(tail)->setNext(newTail);
        return newTail;
    }

    int evalCount() const { return m_evalCount; }

    void appendBinaryExpressionInfo(int& operandStackDepth, ExpressionNode* current, const JSTextPosition& exprStart, const JSTextPosition& lhs, const JSTextPosition& rhs, bool hasAssignments)
    {
        operandStackDepth++;
        m_binaryOperandStack.append(std::make_pair(current, BinaryOpInfo(exprStart, lhs, rhs, hasAssignments)));
    }

    // Logic to handle datastructures used during parsing of binary expressions
    void operatorStackPop(int& operatorStackDepth)
    {
        operatorStackDepth--;
        m_binaryOperatorStack.removeLast();
    }
    bool operatorStackHasHigherPrecedence(int&, int precedence)
    {
        return precedence <= m_binaryOperatorStack.last().second;
    }
    const BinaryOperand& getFromOperandStack(int i) { return m_binaryOperandStack[m_binaryOperandStack.size() + i]; }
    void shrinkOperandStackBy(int& operandStackDepth, int amount)
    {
        operandStackDepth -= amount;
        ASSERT(operandStackDepth >= 0);
        m_binaryOperandStack.resize(m_binaryOperandStack.size() - amount);
    }
    void appendBinaryOperation(const JSTokenLocation& location, int& operandStackDepth, int&, const BinaryOperand& lhs, const BinaryOperand& rhs)
    {
        operandStackDepth++;
        m_binaryOperandStack.append(std::make_pair(makeBinaryNode(location, m_binaryOperatorStack.last().first, lhs, rhs), BinaryOpInfo(lhs.second, rhs.second)));
    }
    void operatorStackAppend(int& operatorStackDepth, int op, int precedence)
    {
        operatorStackDepth++;
        m_binaryOperatorStack.append(std::make_pair(op, precedence));
    }
    ExpressionNode* popOperandStack(int&)
    {
        ExpressionNode* result = m_binaryOperandStack.last().first;
        m_binaryOperandStack.removeLast();
        return result;
    }
    
    void appendUnaryToken(int& tokenStackDepth, int type, const JSTextPosition& start)
    {
        tokenStackDepth++;
        m_unaryTokenStack.append(std::make_pair(type, start));
    }

    int unaryTokenStackLastType(int&)
    {
        return m_unaryTokenStack.last().first;
    }
    
    const JSTextPosition& unaryTokenStackLastStart(int&)
    {
        return m_unaryTokenStack.last().second;
    }
    
    void unaryTokenStackRemoveLast(int& tokenStackDepth)
    {
        tokenStackDepth--;
        m_unaryTokenStack.removeLast();
    }
    
    void assignmentStackAppend(int& assignmentStackDepth, ExpressionNode* node, const JSTextPosition& start, const JSTextPosition& divot, int assignmentCount, Operator op)
    {
        assignmentStackDepth++;
        ASSERT(start.offset >= start.lineStartOffset);
        ASSERT(divot.offset >= divot.lineStartOffset);
        m_assignmentInfoStack.append(AssignmentInfo(node, start, divot, assignmentCount, op));
    }

    ExpressionNode* createAssignment(const JSTokenLocation& location, int& assignmentStackDepth, ExpressionNode* rhs, int initialAssignmentCount, int currentAssignmentCount, const JSTextPosition& lastTokenEnd)
    {
        AssignmentInfo& info = m_assignmentInfoStack.last();
        ExpressionNode* result = makeAssignNode(location, info.m_node, info.m_op, rhs, info.m_initAssignments != initialAssignmentCount, info.m_initAssignments != currentAssignmentCount, info.m_start, info.m_divot + 1, lastTokenEnd);
        m_assignmentInfoStack.removeLast();
        assignmentStackDepth--;
        return result;
    }

    const Identifier* getName(const Property& property) const { return property->name(); }
    PropertyNode::Type getType(const Property& property) const { return property->type(); }

    bool isResolve(ExpressionNode* expr) const { return expr->isResolveNode(); }

    ExpressionNode* createDestructuringAssignment(const JSTokenLocation& location, PassRefPtr<DestructuringPatternNode> pattern, ExpressionNode* initializer)
    {
        return new (m_parserArena) DestructuringAssignmentNode(location, pattern.get(), initializer);
    }
    
    ArrayPattern createArrayPattern(const JSTokenLocation&)
    {
        return ArrayPatternNode::create();
    }
    
    void appendArrayPatternSkipEntry(ArrayPattern node, const JSTokenLocation& location)
    {
        node->appendIndex(ArrayPatternNode::BindingType::Elision, location, 0, nullptr);
    }

    void appendArrayPatternEntry(ArrayPattern node, const JSTokenLocation& location, DestructuringPattern pattern, ExpressionNode* defaultValue)
    {
        node->appendIndex(ArrayPatternNode::BindingType::Element, location, pattern.get(), defaultValue);
    }

    void appendArrayPatternRestEntry(ArrayPattern node, const JSTokenLocation& location, DestructuringPattern pattern)
    {
        node->appendIndex(ArrayPatternNode::BindingType::RestElement, location, pattern.get(), nullptr);
    }

    void finishArrayPattern(ArrayPattern node, const JSTextPosition& divotStart, const JSTextPosition& divot, const JSTextPosition& divotEnd)
    {
        setExceptionLocation(node.get(), divotStart, divot, divotEnd);
    }
    
    ObjectPattern createObjectPattern(const JSTokenLocation&)
    {
        return ObjectPatternNode::create();
    }
    
    void appendObjectPatternEntry(ObjectPattern node, const JSTokenLocation& location, bool wasString, const Identifier& identifier, DestructuringPattern pattern, ExpressionNode* defaultValue)
    {
        node->appendEntry(location, identifier, wasString, pattern.get(), defaultValue);
    }
    
    BindingPattern createBindingLocation(const JSTokenLocation&, const Identifier& boundProperty, const JSTextPosition& start, const JSTextPosition& end)
    {
        return BindingNode::create(boundProperty, start, end);
    }

    void setEndOffset(Node* node, int offset)
    {
        node->setEndOffset(offset);
    }

    int endOffset(Node* node)
    {
        return node->endOffset();
    }

    void setStartOffset(CaseClauseNode* node, int offset)
    {
        node->setStartOffset(offset);
    }

    void setStartOffset(Node* node, int offset)
    {
        node->setStartOffset(offset);
    }
    
private:
    struct Scope {
        Scope()
            : m_features(0)
            , m_numConstants(0)
        {
        }
        DeclarationStacks::VarStack m_varDeclarations;
        DeclarationStacks::FunctionStack m_funcDeclarations;
        int m_features;
        int m_numConstants;
    };

    static void setExceptionLocation(ThrowableExpressionData* node, const JSTextPosition& divotStart, const JSTextPosition& divot, const JSTextPosition& divotEnd)
    {
        ASSERT(divot.offset >= divot.lineStartOffset);
        node->setExceptionSourceCode(divot, divotStart, divotEnd);
    }

    void incConstants() { m_scope.m_numConstants++; }
    void usesThis() { m_scope.m_features |= ThisFeature; }
    void usesCatch() { m_scope.m_features |= CatchFeature; }
    void usesArguments() { m_scope.m_features |= ArgumentsFeature; }
    void usesWith() { m_scope.m_features |= WithFeature; }
    void usesEval() 
    {
        m_evalCount++;
        m_scope.m_features |= EvalFeature;
    }
    ExpressionNode* createIntegerLikeNumber(const JSTokenLocation& location, double d)
    {
        return new (m_parserArena) IntegerNode(location, d);
    }
    ExpressionNode* createDoubleLikeNumber(const JSTokenLocation& location, double d)
    {
        return new (m_parserArena) DoubleNode(location, d);
    }
    ExpressionNode* createNumberFromBinaryOperation(const JSTokenLocation& location, double value, const NumberNode& originalNodeA, const NumberNode& originalNodeB)
    {
        if (originalNodeA.isIntegerNode() && originalNodeB.isIntegerNode())
            return createIntegerLikeNumber(location, value);
        return createDoubleLikeNumber(location, value);
    }
    ExpressionNode* createNumberFromUnaryOperation(const JSTokenLocation& location, double value, const NumberNode& originalNode)
    {
        if (originalNode.isIntegerNode())
            return createIntegerLikeNumber(location, value);
        return createDoubleLikeNumber(location, value);
    }

    VM* m_vm;
    ParserArena& m_parserArena;
    SourceCode* m_sourceCode;
    Scope m_scope;
    Vector<BinaryOperand, 10, UnsafeVectorOverflow> m_binaryOperandStack;
    Vector<AssignmentInfo, 10, UnsafeVectorOverflow> m_assignmentInfoStack;
    Vector<std::pair<int, int>, 10, UnsafeVectorOverflow> m_binaryOperatorStack;
    Vector<std::pair<int, JSTextPosition>, 10, UnsafeVectorOverflow> m_unaryTokenStack;
    int m_evalCount;
};

ExpressionNode* ASTBuilder::makeTypeOfNode(const JSTokenLocation& location, ExpressionNode* expr)
{
    if (expr->isResolveNode()) {
        ResolveNode* resolve = static_cast<ResolveNode*>(expr);
        return new (m_parserArena) TypeOfResolveNode(location, resolve->identifier());
    }
    return new (m_parserArena) TypeOfValueNode(location, expr);
}

ExpressionNode* ASTBuilder::makeDeleteNode(const JSTokenLocation& location, ExpressionNode* expr, const JSTextPosition& start, const JSTextPosition& divot, const JSTextPosition& end)
{
    if (!expr->isLocation())
        return new (m_parserArena) DeleteValueNode(location, expr);
    if (expr->isResolveNode()) {
        ResolveNode* resolve = static_cast<ResolveNode*>(expr);
        return new (m_parserArena) DeleteResolveNode(location, resolve->identifier(), divot, start, end);
    }
    if (expr->isBracketAccessorNode()) {
        BracketAccessorNode* bracket = static_cast<BracketAccessorNode*>(expr);
        return new (m_parserArena) DeleteBracketNode(location, bracket->base(), bracket->subscript(), divot, start, end);
    }
    ASSERT(expr->isDotAccessorNode());
    DotAccessorNode* dot = static_cast<DotAccessorNode*>(expr);
    return new (m_parserArena) DeleteDotNode(location, dot->base(), dot->identifier(), divot, start, end);
}

ExpressionNode* ASTBuilder::makeNegateNode(const JSTokenLocation& location, ExpressionNode* n)
{
    if (n->isNumber()) {
        const NumberNode& numberNode = static_cast<const NumberNode&>(*n);
        return createNumberFromUnaryOperation(location, -numberNode.value(), numberNode);
    }

    return new (m_parserArena) NegateNode(location, n);
}

ExpressionNode* ASTBuilder::makeBitwiseNotNode(const JSTokenLocation& location, ExpressionNode* expr)
{
    if (expr->isNumber())
        return createIntegerLikeNumber(location, ~toInt32(static_cast<NumberNode*>(expr)->value()));
    return new (m_parserArena) BitwiseNotNode(location, expr);
}

ExpressionNode* ASTBuilder::makeMultNode(const JSTokenLocation& location, ExpressionNode* expr1, ExpressionNode* expr2, bool rightHasAssignments)
{
    expr1 = expr1->stripUnaryPlus();
    expr2 = expr2->stripUnaryPlus();

    if (expr1->isNumber() && expr2->isNumber()) {
        const NumberNode& numberExpr1 = static_cast<NumberNode&>(*expr1);
        const NumberNode& numberExpr2 = static_cast<NumberNode&>(*expr2);
        return createNumberFromBinaryOperation(location, numberExpr1.value() * numberExpr2.value(), numberExpr1, numberExpr2);
    }

    if (expr1->isNumber() && static_cast<NumberNode*>(expr1)->value() == 1)
        return new (m_parserArena) UnaryPlusNode(location, expr2);

    if (expr2->isNumber() && static_cast<NumberNode*>(expr2)->value() == 1)
        return new (m_parserArena) UnaryPlusNode(location, expr1);

    return new (m_parserArena) MultNode(location, expr1, expr2, rightHasAssignments);
}

ExpressionNode* ASTBuilder::makeDivNode(const JSTokenLocation& location, ExpressionNode* expr1, ExpressionNode* expr2, bool rightHasAssignments)
{
    expr1 = expr1->stripUnaryPlus();
    expr2 = expr2->stripUnaryPlus();

    if (expr1->isNumber() && expr2->isNumber()) {
        const NumberNode& numberExpr1 = static_cast<NumberNode&>(*expr1);
        const NumberNode& numberExpr2 = static_cast<NumberNode&>(*expr2);
        double result = numberExpr1.value() / numberExpr2.value();
        if (static_cast<int64_t>(result) == result)
            return createNumberFromBinaryOperation(location, result, numberExpr1, numberExpr2);
        return createDoubleLikeNumber(location, result);
    }
    return new (m_parserArena) DivNode(location, expr1, expr2, rightHasAssignments);
}

ExpressionNode* ASTBuilder::makeModNode(const JSTokenLocation& location, ExpressionNode* expr1, ExpressionNode* expr2, bool rightHasAssignments)
{
    expr1 = expr1->stripUnaryPlus();
    expr2 = expr2->stripUnaryPlus();

    if (expr1->isNumber() && expr2->isNumber()) {
        const NumberNode& numberExpr1 = static_cast<NumberNode&>(*expr1);
        const NumberNode& numberExpr2 = static_cast<NumberNode&>(*expr2);
        return createIntegerLikeNumber(location, fmod(numberExpr1.value(), numberExpr2.value()));
    }
    return new (m_parserArena) ModNode(location, expr1, expr2, rightHasAssignments);
}

ExpressionNode* ASTBuilder::makeAddNode(const JSTokenLocation& location, ExpressionNode* expr1, ExpressionNode* expr2, bool rightHasAssignments)
{

    if (expr1->isNumber() && expr2->isNumber()) {
        const NumberNode& numberExpr1 = static_cast<NumberNode&>(*expr1);
        const NumberNode& numberExpr2 = static_cast<NumberNode&>(*expr2);
        return createNumberFromBinaryOperation(location, numberExpr1.value() + numberExpr2.value(), numberExpr1, numberExpr2);
    }
    return new (m_parserArena) AddNode(location, expr1, expr2, rightHasAssignments);
}

ExpressionNode* ASTBuilder::makeSubNode(const JSTokenLocation& location, ExpressionNode* expr1, ExpressionNode* expr2, bool rightHasAssignments)
{
    expr1 = expr1->stripUnaryPlus();
    expr2 = expr2->stripUnaryPlus();

    if (expr1->isNumber() && expr2->isNumber()) {
        const NumberNode& numberExpr1 = static_cast<NumberNode&>(*expr1);
        const NumberNode& numberExpr2 = static_cast<NumberNode&>(*expr2);
        return createNumberFromBinaryOperation(location, numberExpr1.value() - numberExpr2.value(), numberExpr1, numberExpr2);
    }
    return new (m_parserArena) SubNode(location, expr1, expr2, rightHasAssignments);
}

ExpressionNode* ASTBuilder::makeLeftShiftNode(const JSTokenLocation& location, ExpressionNode* expr1, ExpressionNode* expr2, bool rightHasAssignments)
{
    if (expr1->isNumber() && expr2->isNumber()) {
        const NumberNode& numberExpr1 = static_cast<NumberNode&>(*expr1);
        const NumberNode& numberExpr2 = static_cast<NumberNode&>(*expr2);
        return createIntegerLikeNumber(location, toInt32(numberExpr1.value()) << (toUInt32(numberExpr2.value()) & 0x1f));
    }
    return new (m_parserArena) LeftShiftNode(location, expr1, expr2, rightHasAssignments);
}

ExpressionNode* ASTBuilder::makeRightShiftNode(const JSTokenLocation& location, ExpressionNode* expr1, ExpressionNode* expr2, bool rightHasAssignments)
{
    if (expr1->isNumber() && expr2->isNumber()) {
        const NumberNode& numberExpr1 = static_cast<NumberNode&>(*expr1);
        const NumberNode& numberExpr2 = static_cast<NumberNode&>(*expr2);
        return createIntegerLikeNumber(location, toInt32(numberExpr1.value()) >> (toUInt32(numberExpr2.value()) & 0x1f));
    }
    return new (m_parserArena) RightShiftNode(location, expr1, expr2, rightHasAssignments);
}

ExpressionNode* ASTBuilder::makeURightShiftNode(const JSTokenLocation& location, ExpressionNode* expr1, ExpressionNode* expr2, bool rightHasAssignments)
{
    if (expr1->isNumber() && expr2->isNumber()) {
        const NumberNode& numberExpr1 = static_cast<NumberNode&>(*expr1);
        const NumberNode& numberExpr2 = static_cast<NumberNode&>(*expr2);
        return createIntegerLikeNumber(location, toUInt32(numberExpr1.value()) >> (toUInt32(numberExpr2.value()) & 0x1f));
    }
    return new (m_parserArena) UnsignedRightShiftNode(location, expr1, expr2, rightHasAssignments);
}

ExpressionNode* ASTBuilder::makeBitOrNode(const JSTokenLocation& location, ExpressionNode* expr1, ExpressionNode* expr2, bool rightHasAssignments)
{
    if (expr1->isNumber() && expr2->isNumber()) {
        const NumberNode& numberExpr1 = static_cast<NumberNode&>(*expr1);
        const NumberNode& numberExpr2 = static_cast<NumberNode&>(*expr2);
        return createIntegerLikeNumber(location, toInt32(numberExpr1.value()) | toInt32(numberExpr2.value()));
    }
    return new (m_parserArena) BitOrNode(location, expr1, expr2, rightHasAssignments);
}

ExpressionNode* ASTBuilder::makeBitAndNode(const JSTokenLocation& location, ExpressionNode* expr1, ExpressionNode* expr2, bool rightHasAssignments)
{
    if (expr1->isNumber() && expr2->isNumber()) {
        const NumberNode& numberExpr1 = static_cast<NumberNode&>(*expr1);
        const NumberNode& numberExpr2 = static_cast<NumberNode&>(*expr2);
        return createIntegerLikeNumber(location, toInt32(numberExpr1.value()) & toInt32(numberExpr2.value()));
    }
    return new (m_parserArena) BitAndNode(location, expr1, expr2, rightHasAssignments);
}

ExpressionNode* ASTBuilder::makeBitXOrNode(const JSTokenLocation& location, ExpressionNode* expr1, ExpressionNode* expr2, bool rightHasAssignments)
{
    if (expr1->isNumber() && expr2->isNumber()) {
        const NumberNode& numberExpr1 = static_cast<NumberNode&>(*expr1);
        const NumberNode& numberExpr2 = static_cast<NumberNode&>(*expr2);
        return createIntegerLikeNumber(location, toInt32(numberExpr1.value()) ^ toInt32(numberExpr2.value()));
    }
    return new (m_parserArena) BitXOrNode(location, expr1, expr2, rightHasAssignments);
}

ExpressionNode* ASTBuilder::makeFunctionCallNode(const JSTokenLocation& location, ExpressionNode* func, ArgumentsNode* args, const JSTextPosition& divotStart, const JSTextPosition& divot, const JSTextPosition& divotEnd)
{
    ASSERT(divot.offset >= divot.lineStartOffset);
    if (!func->isLocation())
        return new (m_parserArena) FunctionCallValueNode(location, func, args, divot, divotStart, divotEnd);
    if (func->isResolveNode()) {
        ResolveNode* resolve = static_cast<ResolveNode*>(func);
        const Identifier& identifier = resolve->identifier();
        if (identifier == m_vm->propertyNames->eval) {
            usesEval();
            return new (m_parserArena) EvalFunctionCallNode(location, args, divot, divotStart, divotEnd);
        }
        if (BytecodeIntrinsicNode::EmitterType emitter = m_vm->propertyNames->bytecodeIntrinsicRegistry().lookup(identifier))
            return new (m_parserArena) BytecodeIntrinsicNode(location, emitter, identifier, args, divot, divotStart, divotEnd);
        return new (m_parserArena) FunctionCallResolveNode(location, identifier, args, divot, divotStart, divotEnd);
    }
    if (func->isBracketAccessorNode()) {
        BracketAccessorNode* bracket = static_cast<BracketAccessorNode*>(func);
        FunctionCallBracketNode* node = new (m_parserArena) FunctionCallBracketNode(location, bracket->base(), bracket->subscript(), bracket->subscriptHasAssignments(), args, divot, divotStart, divotEnd);
        node->setSubexpressionInfo(bracket->divot(), bracket->divotEnd().offset);
        return node;
    }
    ASSERT(func->isDotAccessorNode());
    DotAccessorNode* dot = static_cast<DotAccessorNode*>(func);
    FunctionCallDotNode* node;
    if (dot->identifier() == m_vm->propertyNames->builtinNames().callPublicName() || dot->identifier() == m_vm->propertyNames->builtinNames().callPrivateName())
        node = new (m_parserArena) CallFunctionCallDotNode(location, dot->base(), dot->identifier(), args, divot, divotStart, divotEnd);
    else if (dot->identifier() == m_vm->propertyNames->builtinNames().applyPublicName() || dot->identifier() == m_vm->propertyNames->builtinNames().applyPrivateName())
        node = new (m_parserArena) ApplyFunctionCallDotNode(location, dot->base(), dot->identifier(), args, divot, divotStart, divotEnd);
    else
        node = new (m_parserArena) FunctionCallDotNode(location, dot->base(), dot->identifier(), args, divot, divotStart, divotEnd);
    node->setSubexpressionInfo(dot->divot(), dot->divotEnd().offset);
    return node;
}

ExpressionNode* ASTBuilder::makeBinaryNode(const JSTokenLocation& location, int token, std::pair<ExpressionNode*, BinaryOpInfo> lhs, std::pair<ExpressionNode*, BinaryOpInfo> rhs)
{
    switch (token) {
    case OR:
        return new (m_parserArena) LogicalOpNode(location, lhs.first, rhs.first, OpLogicalOr);

    case AND:
        return new (m_parserArena) LogicalOpNode(location, lhs.first, rhs.first, OpLogicalAnd);

    case BITOR:
        return makeBitOrNode(location, lhs.first, rhs.first, rhs.second.hasAssignment);

    case BITXOR:
        return makeBitXOrNode(location, lhs.first, rhs.first, rhs.second.hasAssignment);

    case BITAND:
        return makeBitAndNode(location, lhs.first, rhs.first, rhs.second.hasAssignment);

    case EQEQ:
        return new (m_parserArena) EqualNode(location, lhs.first, rhs.first, rhs.second.hasAssignment);

    case NE:
        return new (m_parserArena) NotEqualNode(location, lhs.first, rhs.first, rhs.second.hasAssignment);

    case STREQ:
        return new (m_parserArena) StrictEqualNode(location, lhs.first, rhs.first, rhs.second.hasAssignment);

    case STRNEQ:
        return new (m_parserArena) NotStrictEqualNode(location, lhs.first, rhs.first, rhs.second.hasAssignment);

    case LT:
        return new (m_parserArena) LessNode(location, lhs.first, rhs.first, rhs.second.hasAssignment);

    case GT:
        return new (m_parserArena) GreaterNode(location, lhs.first, rhs.first, rhs.second.hasAssignment);

    case LE:
        return new (m_parserArena) LessEqNode(location, lhs.first, rhs.first, rhs.second.hasAssignment);

    case GE:
        return new (m_parserArena) GreaterEqNode(location, lhs.first, rhs.first, rhs.second.hasAssignment);

    case INSTANCEOF: {
        InstanceOfNode* node = new (m_parserArena) InstanceOfNode(location, lhs.first, rhs.first, rhs.second.hasAssignment);
        setExceptionLocation(node, lhs.second.start, rhs.second.start, rhs.second.end);
        return node;
    }

    case INTOKEN: {
        InNode* node = new (m_parserArena) InNode(location, lhs.first, rhs.first, rhs.second.hasAssignment);
        setExceptionLocation(node, lhs.second.start, rhs.second.start, rhs.second.end);
        return node;
    }

    case LSHIFT:
        return makeLeftShiftNode(location, lhs.first, rhs.first, rhs.second.hasAssignment);

    case RSHIFT:
        return makeRightShiftNode(location, lhs.first, rhs.first, rhs.second.hasAssignment);

    case URSHIFT:
        return makeURightShiftNode(location, lhs.first, rhs.first, rhs.second.hasAssignment);

    case PLUS:
        return makeAddNode(location, lhs.first, rhs.first, rhs.second.hasAssignment);

    case MINUS:
        return makeSubNode(location, lhs.first, rhs.first, rhs.second.hasAssignment);

    case TIMES:
        return makeMultNode(location, lhs.first, rhs.first, rhs.second.hasAssignment);

    case DIVIDE:
        return makeDivNode(location, lhs.first, rhs.first, rhs.second.hasAssignment);

    case MOD:
        return makeModNode(location, lhs.first, rhs.first, rhs.second.hasAssignment);
    }
    CRASH();
    return 0;
}

ExpressionNode* ASTBuilder::makeAssignNode(const JSTokenLocation& location, ExpressionNode* loc, Operator op, ExpressionNode* expr, bool locHasAssignments, bool exprHasAssignments, const JSTextPosition& start, const JSTextPosition& divot, const JSTextPosition& end)
{
    if (!loc->isLocation())
        return new (m_parserArena) AssignErrorNode(location, divot, start, end);

    if (loc->isResolveNode()) {
        ResolveNode* resolve = static_cast<ResolveNode*>(loc);
        if (op == OpEqual) {
            if (expr->isFuncExprNode())
                static_cast<FuncExprNode*>(expr)->body()->setInferredName(resolve->identifier());
            AssignResolveNode* node = new (m_parserArena) AssignResolveNode(location, resolve->identifier(), expr);
            setExceptionLocation(node, start, divot, end);
            return node;
        }
        return new (m_parserArena) ReadModifyResolveNode(location, resolve->identifier(), op, expr, exprHasAssignments, divot, start, end);
    }
    if (loc->isBracketAccessorNode()) {
        BracketAccessorNode* bracket = static_cast<BracketAccessorNode*>(loc);
        if (op == OpEqual)
            return new (m_parserArena) AssignBracketNode(location, bracket->base(), bracket->subscript(), expr, locHasAssignments, exprHasAssignments, bracket->divot(), start, end);
        ReadModifyBracketNode* node = new (m_parserArena) ReadModifyBracketNode(location, bracket->base(), bracket->subscript(), op, expr, locHasAssignments, exprHasAssignments, divot, start, end);
        node->setSubexpressionInfo(bracket->divot(), bracket->divotEnd().offset);
        return node;
    }
    ASSERT(loc->isDotAccessorNode());
    DotAccessorNode* dot = static_cast<DotAccessorNode*>(loc);
    if (op == OpEqual) {
        if (expr->isFuncExprNode())
            static_cast<FuncExprNode*>(expr)->body()->setInferredName(dot->identifier());
        return new (m_parserArena) AssignDotNode(location, dot->base(), dot->identifier(), expr, exprHasAssignments, dot->divot(), start, end);
    }

    ReadModifyDotNode* node = new (m_parserArena) ReadModifyDotNode(location, dot->base(), dot->identifier(), op, expr, exprHasAssignments, divot, start, end);
    node->setSubexpressionInfo(dot->divot(), dot->divotEnd().offset);
    return node;
}

ExpressionNode* ASTBuilder::makePrefixNode(const JSTokenLocation& location, ExpressionNode* expr, Operator op, const JSTextPosition& start, const JSTextPosition& divot, const JSTextPosition& end)
{
    return new (m_parserArena) PrefixNode(location, expr, op, divot, start, end);
}

ExpressionNode* ASTBuilder::makePostfixNode(const JSTokenLocation& location, ExpressionNode* expr, Operator op, const JSTextPosition& start, const JSTextPosition& divot, const JSTextPosition& end)
{
    return new (m_parserArena) PostfixNode(location, expr, op, divot, start, end);
}

}

#endif