JavaScriptCore-7600.1.4.15.12.tar.gz

[apple/javascriptcore.git] / bytecompiler / BytecodeGenerator.h

diff --git a/bytecompiler/BytecodeGenerator.h b/bytecompiler/BytecodeGenerator.h
index e58fcc79d72307c2162eaafbcbe1d90688b13936..5e5ed61416e536b62dfc7cde2c0bdd1fc2a94811 100644 (file)
--- a/bytecompiler/BytecodeGenerator.h
+++ b/bytecompiler/BytecodeGenerator.h
@@ -1,6 +1,7 @@
 /*
 /*

- * Copyright (C) 2008, 2009, 2012 Apple Inc. All rights reserved.
+ * Copyright (C) 2008, 2009, 2012, 2013, 2014 Apple Inc. All rights reserved.

  * Copyright (C) 2008 Cameron Zwarich <cwzwarich@uwaterloo.ca>
  * Copyright (C) 2008 Cameron Zwarich <cwzwarich@uwaterloo.ca>

+ * Copyright (C) 2012 Igalia, S.L.

  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions


@@ -11,7 +12,7 @@
  * 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.
  * 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.

- * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
+ * 3.  Neither the name of Apple Inc. ("Apple") nor the names of

  *     its contributors may be used to endorse or promote products derived
  *     from this software without specific prior written permission.
  *
  *     its contributors may be used to endorse or promote products derived
  *     from this software without specific prior written permission.
  *


@@ -36,37 +37,48 @@
 #include "Label.h"
 #include "LabelScope.h"
 #include "Interpreter.h"
 #include "Label.h"
 #include "LabelScope.h"
 #include "Interpreter.h"

+#include "ParserError.h"

 #include "RegisterID.h"
 #include "SymbolTable.h"
 #include "Debugger.h"
 #include "Nodes.h"
 #include "RegisterID.h"
 #include "SymbolTable.h"
 #include "Debugger.h"
 #include "Nodes.h"

+#include "StaticPropertyAnalyzer.h"
+#include "UnlinkedCodeBlock.h"
+
+#include <functional>
+

 #include <wtf/PassRefPtr.h>
 #include <wtf/SegmentedVector.h>
 #include <wtf/Vector.h>
 
 #include <wtf/PassRefPtr.h>
 #include <wtf/SegmentedVector.h>
 #include <wtf/Vector.h>
 

+

 namespace JSC {
 
     class Identifier;
     class Label;
 namespace JSC {
 
     class Identifier;
     class Label;

-    class ScopeChainNode;
+
+    enum ExpectedFunction {
+        NoExpectedFunction,
+        ExpectObjectConstructor,
+        ExpectArrayConstructor
+    };

 
     class CallArguments {
     public:
 
     class CallArguments {
     public:

-        CallArguments(BytecodeGenerator& generator, ArgumentsNode* argumentsNode);
+        CallArguments(BytecodeGenerator&, ArgumentsNode*, unsigned additionalArguments = 0);

 
         RegisterID* thisRegister() { return m_argv[0].get(); }
         RegisterID* argumentRegister(unsigned i) { return m_argv[i + 1].get(); }
 
         RegisterID* thisRegister() { return m_argv[0].get(); }
         RegisterID* argumentRegister(unsigned i) { return m_argv[i + 1].get(); }

-        unsigned registerOffset() { return m_argv.last()->index() + CallFrame::offsetFor(argumentCountIncludingThis()); }
-        unsigned argumentCountIncludingThis() { return m_argv.size(); }
+        unsigned stackOffset() { return -m_argv[0]->index() + JSStack::CallFrameHeaderSize; }
+        unsigned argumentCountIncludingThis() { return m_argv.size() - m_padding; }

         RegisterID* profileHookRegister() { return m_profileHookRegister.get(); }
         ArgumentsNode* argumentsNode() { return m_argumentsNode; }
 
     private:
         RegisterID* profileHookRegister() { return m_profileHookRegister.get(); }
         ArgumentsNode* argumentsNode() { return m_argumentsNode; }
 
     private:

-        void newArgument(BytecodeGenerator&);
-

         RefPtr<RegisterID> m_profileHookRegister;
         ArgumentsNode* m_argumentsNode;
         RefPtr<RegisterID> m_profileHookRegister;
         ArgumentsNode* m_argumentsNode;

-        Vector<RefPtr<RegisterID>, 8> m_argv;
+        Vector<RefPtr<RegisterID>, 8, UnsafeVectorOverflow> m_argv;
+        unsigned m_padding;

     };
 
     struct FinallyContext {
     };
 
     struct FinallyContext {


@@ -74,6 +86,7 @@ namespace JSC {
         unsigned scopeContextStackSize;
         unsigned switchContextStackSize;
         unsigned forInContextStackSize;
         unsigned scopeContextStackSize;
         unsigned switchContextStackSize;
         unsigned forInContextStackSize;

+        unsigned tryContextStackSize;

         unsigned labelScopesSize;
         int finallyDepth;
         int dynamicScopeDepth;
         unsigned labelScopesSize;
         int finallyDepth;
         int dynamicScopeDepth;


@@ -91,32 +104,75 @@ namespace JSC {
         RefPtr<RegisterID> propertyRegister;
     };
 
         RefPtr<RegisterID> propertyRegister;
     };
 

+    struct TryData {
+        RefPtr<Label> target;
+        unsigned targetScopeDepth;
+    };
+
+    struct TryContext {
+        RefPtr<Label> start;
+        TryData* tryData;
+    };
+
+    enum CaptureMode {
+        NotCaptured,
+        IsCaptured
+    };
+
+    class Local {
+    public:
+        Local()
+            : m_local(0)
+            , m_attributes(0)
+        {
+        }
+
+        Local(RegisterID* local, unsigned attributes, CaptureMode captureMode)
+            : m_local(local)
+            , m_attributes(attributes)
+            , m_isCaptured(captureMode == IsCaptured)
+        {
+        }
+
+        operator bool() { return m_local; }
+
+        RegisterID* get() { return m_local; }
+
+        bool isReadOnly() { return m_attributes & ReadOnly; }
+        
+        bool isCaptured() { return m_isCaptured; }
+        CaptureMode captureMode() { return isCaptured() ? IsCaptured : NotCaptured; }
+
+    private:
+        RegisterID* m_local;
+        unsigned m_attributes;
+        bool m_isCaptured;
+    };
+
+    struct TryRange {
+        RefPtr<Label> start;
+        RefPtr<Label> end;
+        TryData* tryData;
+    };
+

     class BytecodeGenerator {
         WTF_MAKE_FAST_ALLOCATED;
     public:
         typedef DeclarationStacks::VarStack VarStack;
         typedef DeclarationStacks::FunctionStack FunctionStack;
 
     class BytecodeGenerator {
         WTF_MAKE_FAST_ALLOCATED;
     public:
         typedef DeclarationStacks::VarStack VarStack;
         typedef DeclarationStacks::FunctionStack FunctionStack;
 

-        JS_EXPORT_PRIVATE static void setDumpsGeneratedCode(bool dumpsGeneratedCode);
-        static bool dumpsGeneratedCode();
-
-        BytecodeGenerator(ProgramNode*, ScopeChainNode*, SymbolTable*, ProgramCodeBlock*, CompilationKind);
-        BytecodeGenerator(FunctionBodyNode*, ScopeChainNode*, SymbolTable*, CodeBlock*, CompilationKind);
-        BytecodeGenerator(EvalNode*, ScopeChainNode*, SymbolTable*, EvalCodeBlock*, CompilationKind);
+        BytecodeGenerator(VM&, ProgramNode*, UnlinkedProgramCodeBlock*, DebuggerMode, ProfilerMode);
+        BytecodeGenerator(VM&, FunctionBodyNode*, UnlinkedFunctionCodeBlock*, DebuggerMode, ProfilerMode);
+        BytecodeGenerator(VM&, EvalNode*, UnlinkedEvalCodeBlock*, DebuggerMode, ProfilerMode);

 
         ~BytecodeGenerator();
         
 
         ~BytecodeGenerator();
         

-        JSGlobalData* globalData() const { return m_globalData; }
-        const CommonIdentifiers& propertyNames() const { return *m_globalData->propertyNames; }
-
-        bool isConstructor() { return m_codeBlock->m_isConstructor; }
+        VM* vm() const { return m_vm; }
+        const CommonIdentifiers& propertyNames() const { return *m_vm->propertyNames; }

 
 

-        JSObject* generate();
+        bool isConstructor() { return m_codeBlock->isConstructor(); }

 
 

-        // Returns the register corresponding to a local variable, or 0 if no
-        // such register exists. Registers returned by registerFor do not
-        // require explicit reference counting.
-        RegisterID* registerFor(const Identifier&);
+        ParserError generate();

 
         bool isArgumentNumber(const Identifier&, int);
 
 
         bool isArgumentNumber(const Identifier&, int);
 


@@ -125,32 +181,21 @@ namespace JSC {
         bool willResolveToArguments(const Identifier&);
         RegisterID* uncheckedRegisterForArguments();
 
         bool willResolveToArguments(const Identifier&);
         RegisterID* uncheckedRegisterForArguments();
 

-        // Behaves as registerFor does, but ignores dynamic scope as
-        // dynamic scope should not interfere with const initialisation
-        RegisterID* constRegisterFor(const Identifier&);
-
-        // Searches the scope chain in an attempt to  statically locate the requested
-        // property. Returns false if for any reason the property cannot be safely
-        // optimised at all. Otherwise it will return the index and depth of the
-        // VariableObject that defines the property. If the property cannot be found
-        // statically, depth will contain the depth of the scope chain where dynamic
-        // lookup must begin.
-        bool findScopedProperty(const Identifier&, int& index, size_t& depth, bool forWriting, bool& includesDynamicScopes, JSObject*& globalObject);
+        bool isCaptured(int operand);
+        CaptureMode captureMode(int operand) { return isCaptured(operand) ? IsCaptured : NotCaptured; }
+        
+        Local local(const Identifier&);
+        Local constLocal(const Identifier&);

 
         // Returns the register storing "this"
         RegisterID* thisRegister() { return &m_thisRegister; }
 
 
         // Returns the register storing "this"
         RegisterID* thisRegister() { return &m_thisRegister; }
 

-        bool isLocal(const Identifier&);
-        bool isLocalConstant(const Identifier&);
-

         // Returns the next available temporary register. Registers returned by
         // newTemporary require a modified form of reference counting: any
         // register with a refcount of 0 is considered "available", meaning that
         // the next instruction may overwrite it.
         RegisterID* newTemporary();
 
         // Returns the next available temporary register. Registers returned by
         // newTemporary require a modified form of reference counting: any
         // register with a refcount of 0 is considered "available", meaning that
         // the next instruction may overwrite it.
         RegisterID* newTemporary();
 

-        RegisterID* highestUsedRegister();
-

         // The same as newTemporary(), but this function returns "suggestion" if
         // "suggestion" is a temporary. This function is helpful in situations
         // where you've put "suggestion" in a RefPtr, but you'd like to allow
         // The same as newTemporary(), but this function returns "suggestion" if
         // "suggestion" is a temporary. This function is helpful in situations
         // where you've put "suggestion" in a RefPtr, but you'd like to allow


@@ -179,17 +224,6 @@ namespace JSC {
             return newTemporary();
         }
 
             return newTemporary();
         }
 

-        // Returns the place to write the final output of an operation.
-        RegisterID* finalDestinationOrIgnored(RegisterID* originalDst, RegisterID* tempDst = 0)
-        {
-            if (originalDst)
-                return originalDst;
-            ASSERT(tempDst != ignoredResult());
-            if (tempDst && tempDst->isTemporary())
-                return tempDst;
-            return newTemporary();
-        }
-

         RegisterID* destinationForAssignResult(RegisterID* dst)
         {
             if (dst && dst != ignoredResult() && m_codeBlock->needsFullScopeChain())
         RegisterID* destinationForAssignResult(RegisterID* dst)
         {
             if (dst && dst != ignoredResult() && m_codeBlock->needsFullScopeChain())


@@ -203,68 +237,83 @@ namespace JSC {
             return dst == ignoredResult() ? 0 : (dst && dst != src) ? emitMove(dst, src) : src;
         }
 
             return dst == ignoredResult() ? 0 : (dst && dst != src) ? emitMove(dst, src) : src;
         }
 

-        PassRefPtr<LabelScope> newLabelScope(LabelScope::Type, const Identifier* = 0);
+        LabelScopePtr newLabelScope(LabelScope::Type, const Identifier* = 0);

         PassRefPtr<Label> newLabel();
 
         PassRefPtr<Label> newLabel();
 

-        // The emitNode functions are just syntactic sugar for calling
-        // Node::emitCode. These functions accept a 0 for the register,
-        // meaning that the node should allocate a register, or ignoredResult(),
-        // meaning that the node need not put the result in a register.
-        // Other emit functions do not accept 0 or ignoredResult().
-        RegisterID* emitNode(RegisterID* dst, Node* n)
+        void emitNode(RegisterID* dst, StatementNode* n)
+        {
+            // Node::emitCode assumes that dst, if provided, is either a local or a referenced temporary.
+            ASSERT(!dst || dst == ignoredResult() || !dst->isTemporary() || dst->refCount());
+            // Should never store directly into a captured variable.
+            ASSERT(!dst || dst == ignoredResult() || !isCaptured(dst->index()));
+            if (!m_vm->isSafeToRecurse()) {
+                emitThrowExpressionTooDeepException();
+                return;
+            }
+            n->emitBytecode(*this, dst);
+        }
+
+        void emitNode(StatementNode* n)
+        {
+            emitNode(0, n);
+        }
+
+        RegisterID* emitNode(RegisterID* dst, ExpressionNode* n)

         {
             // Node::emitCode assumes that dst, if provided, is either a local or a referenced temporary.
             ASSERT(!dst || dst == ignoredResult() || !dst->isTemporary() || dst->refCount());
         {
             // Node::emitCode assumes that dst, if provided, is either a local or a referenced temporary.
             ASSERT(!dst || dst == ignoredResult() || !dst->isTemporary() || dst->refCount());

-            addLineInfo(n->lineNo());
-            return m_stack.recursionCheck()
-                ? n->emitBytecode(*this, dst)
-                : emitThrowExpressionTooDeepException();
+            // Should never store directly into a captured variable.
+            ASSERT(!dst || dst == ignoredResult() || !isCaptured(dst->index()));
+            if (!m_vm->isSafeToRecurse())
+                return emitThrowExpressionTooDeepException();
+            return n->emitBytecode(*this, dst);

         }
 
         }
 

-        RegisterID* emitNode(Node* n)
+        RegisterID* emitNode(ExpressionNode* n)

         {
             return emitNode(0, n);
         }
 
         {
             return emitNode(0, n);
         }
 

-        void emitNodeInConditionContext(ExpressionNode* n, Label* trueTarget, Label* falseTarget, bool fallThroughMeansTrue)
+        void emitNodeInConditionContext(ExpressionNode* n, Label* trueTarget, Label* falseTarget, FallThroughMode fallThroughMode)

         {
         {

-            addLineInfo(n->lineNo());
-            if (m_stack.recursionCheck())
-                n->emitBytecodeInConditionContext(*this, trueTarget, falseTarget, fallThroughMeansTrue);
-            else
+            if (!m_vm->isSafeToRecurse()) {

                 emitThrowExpressionTooDeepException();
                 emitThrowExpressionTooDeepException();

+                return;
+            }
+
+            n->emitBytecodeInConditionContext(*this, trueTarget, falseTarget, fallThroughMode);

         }
 
         }
 

-        void emitExpressionInfo(unsigned divot, unsigned startOffset, unsigned endOffset)
-        {
-            if (!m_shouldEmitRichSourceInfo)
+        void emitExpressionInfo(const JSTextPosition& divot, const JSTextPosition& divotStart, const JSTextPosition& divotEnd)
+        {            
+            ASSERT(divot.offset >= divotStart.offset);
+            ASSERT(divotEnd.offset >= divot.offset);
+
+            int sourceOffset = m_scopeNode->source().startOffset();
+            unsigned firstLine = m_scopeNode->source().firstLine();
+
+            int divotOffset = divot.offset - sourceOffset;
+            int startOffset = divot.offset - divotStart.offset;
+            int endOffset = divotEnd.offset - divot.offset;
+
+            unsigned line = divot.line;
+            ASSERT(line >= firstLine);
+            line -= firstLine;
+
+            int lineStart = divot.lineStartOffset;
+            if (lineStart > sourceOffset)
+                lineStart -= sourceOffset;
+            else
+                lineStart = 0;
+
+            if (divotOffset < lineStart)

                 return;
 
                 return;
 

-            divot -= m_codeBlock->sourceOffset();
-            if (divot > ExpressionRangeInfo::MaxDivot) {
-                // Overflow has occurred, we can only give line number info for errors for this region
-                divot = 0;
-                startOffset = 0;
-                endOffset = 0;
-            } else if (startOffset > ExpressionRangeInfo::MaxOffset) {
-                // If the start offset is out of bounds we clear both offsets
-                // so we only get the divot marker.  Error message will have to be reduced
-                // to line and column number.
-                startOffset = 0;
-                endOffset = 0;
-            } else if (endOffset > ExpressionRangeInfo::MaxOffset) {
-                // The end offset is only used for additional context, and is much more likely
-                // to overflow (eg. function call arguments) so we are willing to drop it without
-                // dropping the rest of the range.
-                endOffset = 0;
-            }
-            
-            ExpressionRangeInfo info;
-            info.instructionOffset = instructions().size();
-            info.divotPoint = divot;
-            info.startOffset = startOffset;
-            info.endOffset = endOffset;
-            m_codeBlock->addExpressionInfo(info);
+            unsigned column = divotOffset - lineStart;
+
+            unsigned instructionOffset = instructions().size();
+            if (!m_isBuiltinFunction)
+                m_codeBlock->addExpressionInfo(instructionOffset, divotOffset, startOffset, endOffset, line, column);

         }
 
         ALWAYS_INLINE bool leftHandSideNeedsCopy(bool rightHasAssignments, bool rightIsPure)
         }
 
         ALWAYS_INLINE bool leftHandSideNeedsCopy(bool rightHasAssignments, bool rightIsPure)


@@ -287,44 +336,36 @@ namespace JSC {
         RegisterID* emitLoad(RegisterID* dst, double);
         RegisterID* emitLoad(RegisterID* dst, const Identifier&);
         RegisterID* emitLoad(RegisterID* dst, JSValue);
         RegisterID* emitLoad(RegisterID* dst, double);
         RegisterID* emitLoad(RegisterID* dst, const Identifier&);
         RegisterID* emitLoad(RegisterID* dst, JSValue);

+        RegisterID* emitLoadGlobalObject(RegisterID* dst);

 
         RegisterID* emitUnaryOp(OpcodeID, RegisterID* dst, RegisterID* src);
         RegisterID* emitBinaryOp(OpcodeID, RegisterID* dst, RegisterID* src1, RegisterID* src2, OperandTypes);
         RegisterID* emitEqualityOp(OpcodeID, RegisterID* dst, RegisterID* src1, RegisterID* src2);
         RegisterID* emitUnaryNoDstOp(OpcodeID, RegisterID* src);
 
 
         RegisterID* emitUnaryOp(OpcodeID, RegisterID* dst, RegisterID* src);
         RegisterID* emitBinaryOp(OpcodeID, RegisterID* dst, RegisterID* src1, RegisterID* src2, OperandTypes);
         RegisterID* emitEqualityOp(OpcodeID, RegisterID* dst, RegisterID* src1, RegisterID* src2);
         RegisterID* emitUnaryNoDstOp(OpcodeID, RegisterID* src);
 

+        RegisterID* emitCreateThis(RegisterID* dst);

         RegisterID* emitNewObject(RegisterID* dst);
         RegisterID* emitNewArray(RegisterID* dst, ElementNode*, unsigned length); // stops at first elision
 
         RegisterID* emitNewObject(RegisterID* dst);
         RegisterID* emitNewArray(RegisterID* dst, ElementNode*, unsigned length); // stops at first elision
 

-        RegisterID* emitNewFunction(RegisterID* dst, FunctionBodyNode* body);
+        RegisterID* emitNewFunction(RegisterID* dst, CaptureMode, FunctionBodyNode*);

         RegisterID* emitLazyNewFunction(RegisterID* dst, FunctionBodyNode* body);
         RegisterID* emitLazyNewFunction(RegisterID* dst, FunctionBodyNode* body);

-        RegisterID* emitNewFunctionInternal(RegisterID* dst, unsigned index, bool shouldNullCheck);
+        RegisterID* emitNewFunctionInternal(RegisterID* dst, CaptureMode, unsigned index, bool shouldNullCheck);

         RegisterID* emitNewFunctionExpression(RegisterID* dst, FuncExprNode* func);
         RegisterID* emitNewRegExp(RegisterID* dst, RegExp*);
 
         RegisterID* emitNewFunctionExpression(RegisterID* dst, FuncExprNode* func);
         RegisterID* emitNewRegExp(RegisterID* dst, RegExp*);
 

+        RegisterID* emitMove(RegisterID* dst, CaptureMode, RegisterID* src);

         RegisterID* emitMove(RegisterID* dst, RegisterID* src);
 
         RegisterID* emitMove(RegisterID* dst, RegisterID* src);
 

-        RegisterID* emitToJSNumber(RegisterID* dst, RegisterID* src) { return emitUnaryOp(op_to_jsnumber, dst, src); }
-        RegisterID* emitPreInc(RegisterID* srcDst);
-        RegisterID* emitPreDec(RegisterID* srcDst);
-        RegisterID* emitPostInc(RegisterID* dst, RegisterID* srcDst);
-        RegisterID* emitPostDec(RegisterID* dst, RegisterID* srcDst);
+        RegisterID* emitToNumber(RegisterID* dst, RegisterID* src) { return emitUnaryOp(op_to_number, dst, src); }
+        RegisterID* emitInc(RegisterID* srcDst);
+        RegisterID* emitDec(RegisterID* srcDst);

 
 

-        void emitCheckHasInstance(RegisterID* base);
-        RegisterID* emitInstanceOf(RegisterID* dst, RegisterID* value, RegisterID* base, RegisterID* basePrototype);
+        void emitCheckHasInstance(RegisterID* dst, RegisterID* value, RegisterID* base, Label* target);
+        RegisterID* emitInstanceOf(RegisterID* dst, RegisterID* value, RegisterID* basePrototype);

         RegisterID* emitTypeOf(RegisterID* dst, RegisterID* src) { return emitUnaryOp(op_typeof, dst, src); }
         RegisterID* emitIn(RegisterID* dst, RegisterID* property, RegisterID* base) { return emitBinaryOp(op_in, dst, property, base, OperandTypes()); }
 
         RegisterID* emitTypeOf(RegisterID* dst, RegisterID* src) { return emitUnaryOp(op_typeof, dst, src); }
         RegisterID* emitIn(RegisterID* dst, RegisterID* property, RegisterID* base) { return emitBinaryOp(op_in, dst, property, base, OperandTypes()); }
 

-        RegisterID* emitResolve(RegisterID* dst, const Identifier& property);
-        RegisterID* emitGetScopedVar(RegisterID* dst, size_t skip, int index, JSValue globalObject);
-        RegisterID* emitPutScopedVar(size_t skip, int index, RegisterID* value, JSValue globalObject);
-
-        RegisterID* emitResolveBase(RegisterID* dst, const Identifier& property);
-        RegisterID* emitResolveBaseForPut(RegisterID* dst, const Identifier& property);
-        RegisterID* emitResolveWithBase(RegisterID* baseDst, RegisterID* propDst, const Identifier& property);
-        RegisterID* emitResolveWithThis(RegisterID* baseDst, RegisterID* propDst, const Identifier& property);
-
-        void emitMethodCheck();
+        RegisterID* emitInitGlobalConst(const Identifier&, RegisterID* value);

 
         RegisterID* emitGetById(RegisterID* dst, RegisterID* base, const Identifier& property);
         RegisterID* emitGetArgumentsLength(RegisterID* dst, RegisterID* base);
 
         RegisterID* emitGetById(RegisterID* dst, RegisterID* base, const Identifier& property);
         RegisterID* emitGetArgumentsLength(RegisterID* dst, RegisterID* base);


@@ -334,22 +375,30 @@ namespace JSC {
         RegisterID* emitGetByVal(RegisterID* dst, RegisterID* base, RegisterID* property);
         RegisterID* emitGetArgumentByVal(RegisterID* dst, RegisterID* base, RegisterID* property);
         RegisterID* emitPutByVal(RegisterID* base, RegisterID* property, RegisterID* value);
         RegisterID* emitGetByVal(RegisterID* dst, RegisterID* base, RegisterID* property);
         RegisterID* emitGetArgumentByVal(RegisterID* dst, RegisterID* base, RegisterID* property);
         RegisterID* emitPutByVal(RegisterID* base, RegisterID* property, RegisterID* value);

+        RegisterID* emitDirectPutByVal(RegisterID* base, RegisterID* property, RegisterID* value);

         RegisterID* emitDeleteByVal(RegisterID* dst, RegisterID* base, RegisterID* property);
         RegisterID* emitPutByIndex(RegisterID* base, unsigned index, RegisterID* value);
         void emitPutGetterSetter(RegisterID* base, const Identifier& property, RegisterID* getter, RegisterID* setter);
         RegisterID* emitDeleteByVal(RegisterID* dst, RegisterID* base, RegisterID* property);
         RegisterID* emitPutByIndex(RegisterID* base, unsigned index, RegisterID* value);
         void emitPutGetterSetter(RegisterID* base, const Identifier& property, RegisterID* getter, RegisterID* setter);

+        
+        ExpectedFunction expectedFunctionForIdentifier(const Identifier&);
+        RegisterID* emitCall(RegisterID* dst, RegisterID* func, ExpectedFunction, CallArguments&, const JSTextPosition& divot, const JSTextPosition& divotStart, const JSTextPosition& divotEnd);
+        RegisterID* emitCallEval(RegisterID* dst, RegisterID* func, CallArguments&, const JSTextPosition& divot, const JSTextPosition& divotStart, const JSTextPosition& divotEnd);
+        RegisterID* emitCallVarargs(RegisterID* dst, RegisterID* func, RegisterID* thisRegister, RegisterID* arguments, RegisterID* firstFreeRegister, int32_t firstVarArgOffset, RegisterID* profileHookRegister, const JSTextPosition& divot, const JSTextPosition& divotStart, const JSTextPosition& divotEnd);

 
 

-        RegisterID* emitCall(RegisterID* dst, RegisterID* func, CallArguments&, unsigned divot, unsigned startOffset, unsigned endOffset);
-        RegisterID* emitCallEval(RegisterID* dst, RegisterID* func, CallArguments&, unsigned divot, unsigned startOffset, unsigned endOffset);
-        RegisterID* emitCallVarargs(RegisterID* dst, RegisterID* func, RegisterID* thisRegister, RegisterID* arguments, RegisterID* firstFreeRegister, RegisterID* profileHookRegister, unsigned divot, unsigned startOffset, unsigned endOffset);
-        RegisterID* emitLoadVarargs(RegisterID* argCountDst, RegisterID* thisRegister, RegisterID* args);
-
+        void emitEnumeration(ThrowableExpressionData* enumerationNode, ExpressionNode* subjectNode, const std::function<void(BytecodeGenerator&, RegisterID*)>& callBack);
+        

         RegisterID* emitReturn(RegisterID* src);
         RegisterID* emitEnd(RegisterID* src) { return emitUnaryNoDstOp(op_end, src); }
 
         RegisterID* emitReturn(RegisterID* src);
         RegisterID* emitEnd(RegisterID* src) { return emitUnaryNoDstOp(op_end, src); }
 

-        RegisterID* emitConstruct(RegisterID* dst, RegisterID* func, CallArguments&, unsigned divot, unsigned startOffset, unsigned endOffset);
+        RegisterID* emitConstruct(RegisterID* dst, RegisterID* func, ExpectedFunction, CallArguments&, const JSTextPosition& divot, const JSTextPosition& divotStart, const JSTextPosition& divotEnd);

         RegisterID* emitStrcat(RegisterID* dst, RegisterID* src, int count);
         void emitToPrimitive(RegisterID* dst, RegisterID* src);
 
         RegisterID* emitStrcat(RegisterID* dst, RegisterID* src, int count);
         void emitToPrimitive(RegisterID* dst, RegisterID* src);
 

+        ResolveType resolveType();
+        RegisterID* emitResolveScope(RegisterID* dst, const Identifier&);
+        RegisterID* emitGetFromScope(RegisterID* dst, RegisterID* scope, const Identifier&, ResolveMode);
+        RegisterID* emitPutToScope(RegisterID* scope, const Identifier&, RegisterID* value, ResolveMode);
+

         PassRefPtr<Label> emitLabel(Label*);
         void emitLoopHint();
         PassRefPtr<Label> emitJump(Label* target);
         PassRefPtr<Label> emitLabel(Label*);
         void emitLoopHint();
         PassRefPtr<Label> emitJump(Label* target);


@@ -357,36 +406,43 @@ namespace JSC {
         PassRefPtr<Label> emitJumpIfFalse(RegisterID* cond, Label* target);
         PassRefPtr<Label> emitJumpIfNotFunctionCall(RegisterID* cond, Label* target);
         PassRefPtr<Label> emitJumpIfNotFunctionApply(RegisterID* cond, Label* target);
         PassRefPtr<Label> emitJumpIfFalse(RegisterID* cond, Label* target);
         PassRefPtr<Label> emitJumpIfNotFunctionCall(RegisterID* cond, Label* target);
         PassRefPtr<Label> emitJumpIfNotFunctionApply(RegisterID* cond, Label* target);

-        PassRefPtr<Label> emitJumpScopes(Label* target, int targetScopeDepth);
+        void emitPopScopes(int targetScopeDepth);

 
         RegisterID* emitGetPropertyNames(RegisterID* dst, RegisterID* base, RegisterID* i, RegisterID* size, Label* breakTarget);
         RegisterID* emitNextPropertyName(RegisterID* dst, RegisterID* base, RegisterID* i, RegisterID* size, RegisterID* iter, Label* target);
 
 
         RegisterID* emitGetPropertyNames(RegisterID* dst, RegisterID* base, RegisterID* i, RegisterID* size, Label* breakTarget);
         RegisterID* emitNextPropertyName(RegisterID* dst, RegisterID* base, RegisterID* i, RegisterID* size, RegisterID* iter, Label* target);
 

-        RegisterID* emitCatch(RegisterID*, Label* start, Label* end);
+        void emitReadOnlyExceptionIfNeeded();
+
+        // Start a try block. 'start' must have been emitted.
+        TryData* pushTry(Label* start);
+        // End a try block. 'end' must have been emitted.
+        RegisterID* popTryAndEmitCatch(TryData*, RegisterID* targetRegister, Label* end);
+

         void emitThrow(RegisterID* exc)
         { 
             m_usesExceptions = true;
             emitUnaryNoDstOp(op_throw, exc);
         }
 
         void emitThrow(RegisterID* exc)
         { 
             m_usesExceptions = true;
             emitUnaryNoDstOp(op_throw, exc);
         }
 

-        void emitThrowReferenceError(const UString& message);
+        void emitThrowReferenceError(const String& message);

 
 

-        void emitPushNewScope(RegisterID* dst, const Identifier& property, RegisterID* value);
+        void emitPushFunctionNameScope(const Identifier& property, RegisterID* value, unsigned attributes);
+        void emitPushCatchScope(const Identifier& property, RegisterID* value, unsigned attributes);

 
 

-        RegisterID* emitPushScope(RegisterID* scope);
+        RegisterID* emitPushWithScope(RegisterID* scope);

         void emitPopScope();
 
         void emitPopScope();
 

-        void emitDebugHook(DebugHookID, int firstLine, int lastLine);
+        void emitDebugHook(DebugHookID, unsigned line, unsigned charOffset, unsigned lineStart);

 
 

-        int scopeDepth() { return m_dynamicScopeDepth + m_finallyDepth; }
+        int scopeDepth() { return m_localScopeDepth + m_finallyDepth; }

         bool hasFinaliser() { return m_finallyDepth != 0; }
 
         void pushFinallyContext(StatementNode* finallyBlock);
         void popFinallyContext();
 
         bool hasFinaliser() { return m_finallyDepth != 0; }
 
         void pushFinallyContext(StatementNode* finallyBlock);
         void popFinallyContext();
 

-        void pushOptimisedForIn(RegisterID* expectedBase, RegisterID* iter, RegisterID* index, RegisterID* propertyRegister)
+        void pushOptimisedForIn(RegisterID* expectedSubscript, RegisterID* iter, RegisterID* index, RegisterID* propertyRegister)

         {
         {

-            ForInContext context = { expectedBase, iter, index, propertyRegister };
+            ForInContext context = { expectedSubscript, iter, index, propertyRegister };

             m_forInContextStack.append(context);
         }
 
             m_forInContextStack.append(context);
         }
 


@@ -395,8 +451,8 @@ namespace JSC {
             m_forInContextStack.removeLast();
         }
 
             m_forInContextStack.removeLast();
         }
 

-        LabelScope* breakTarget(const Identifier&);
-        LabelScope* continueTarget(const Identifier&);
+        LabelScopePtr breakTarget(const Identifier&);
+        LabelScopePtr continueTarget(const Identifier&);

 
         void beginSwitch(RegisterID*, SwitchInfo::SwitchType);
         void endSwitch(uint32_t clauseCount, RefPtr<Label>*, ExpressionNode**, Label* defaultLabel, int32_t min, int32_t range);
 
         void beginSwitch(RegisterID*, SwitchInfo::SwitchType);
         void endSwitch(uint32_t clauseCount, RefPtr<Label>*, ExpressionNode**, Label* defaultLabel, int32_t min, int32_t range);


@@ -404,40 +460,57 @@ namespace JSC {
         CodeType codeType() const { return m_codeType; }
 
         bool shouldEmitProfileHooks() { return m_shouldEmitProfileHooks; }
         CodeType codeType() const { return m_codeType; }
 
         bool shouldEmitProfileHooks() { return m_shouldEmitProfileHooks; }

+        bool shouldEmitDebugHooks() { return m_shouldEmitDebugHooks; }

         
         bool isStrictMode() const { return m_codeBlock->isStrictMode(); }
         
         
         bool isStrictMode() const { return m_codeBlock->isStrictMode(); }
         

-        ScopeChainNode* scopeChain() const { return m_scopeChain.get(); }
-
+        bool isBuiltinFunction() const { return m_isBuiltinFunction; }
+        

     private:
         friend class Label;
         
         void emitOpcode(OpcodeID);
     private:
         friend class Label;
         
         void emitOpcode(OpcodeID);

-        ValueProfile* emitProfiledOpcode(OpcodeID);
+        UnlinkedArrayAllocationProfile newArrayAllocationProfile();
+        UnlinkedObjectAllocationProfile newObjectAllocationProfile();
+        UnlinkedArrayProfile newArrayProfile();
+        UnlinkedValueProfile emitProfiledOpcode(OpcodeID);
+        int kill(RegisterID* dst)
+        {
+            int index = dst->index();
+            m_staticPropertyAnalyzer.kill(index);
+            return index;
+        }
+

         void retrieveLastBinaryOp(int& dstIndex, int& src1Index, int& src2Index);
         void retrieveLastUnaryOp(int& dstIndex, int& srcIndex);
         ALWAYS_INLINE void rewindBinaryOp();
         ALWAYS_INLINE void rewindUnaryOp();
 
         void retrieveLastBinaryOp(int& dstIndex, int& src1Index, int& src2Index);
         void retrieveLastUnaryOp(int& dstIndex, int& srcIndex);
         ALWAYS_INLINE void rewindBinaryOp();
         ALWAYS_INLINE void rewindUnaryOp();
 

-        PassRefPtr<Label> emitComplexJumpScopes(Label* target, ControlFlowContext* topScope, ControlFlowContext* bottomScope);
+        void emitComplexPopScopes(ControlFlowContext* topScope, ControlFlowContext* bottomScope);

 
         typedef HashMap<double, JSValue> NumberMap;
         typedef HashMap<StringImpl*, JSString*, IdentifierRepHash> IdentifierStringMap;
         
 
         typedef HashMap<double, JSValue> NumberMap;
         typedef HashMap<StringImpl*, JSString*, IdentifierRepHash> IdentifierStringMap;
         

-        RegisterID* emitCall(OpcodeID, RegisterID* dst, RegisterID* func, CallArguments&, unsigned divot, unsigned startOffset, unsigned endOffset);
+        // Helper for emitCall() and emitConstruct(). This works because the set of
+        // expected functions have identical behavior for both call and construct
+        // (i.e. "Object()" is identical to "new Object()").
+        ExpectedFunction emitExpectedFunctionSnippet(RegisterID* dst, RegisterID* func, ExpectedFunction, CallArguments&, Label* done);
+        
+        RegisterID* emitCall(OpcodeID, RegisterID* dst, RegisterID* func, ExpectedFunction, CallArguments&, const JSTextPosition& divot, const JSTextPosition& divotStart, const JSTextPosition& divotEnd);

 
         RegisterID* newRegister();
 
         // Adds a var slot and maps it to the name ident in symbolTable().
 
         RegisterID* newRegister();
 
         // Adds a var slot and maps it to the name ident in symbolTable().

-        RegisterID* addVar(const Identifier& ident, bool isConstant)
+        enum WatchMode { IsWatchable, NotWatchable };
+        RegisterID* addVar(const Identifier& ident, ConstantMode constantMode, WatchMode watchMode)

         {
             RegisterID* local;
         {
             RegisterID* local;

-            addVar(ident, isConstant, local);
+            addVar(ident, constantMode, watchMode, local);

             return local;
         }
 
         // Ditto. Returns true if a new RegisterID was added, false if a pre-existing RegisterID was re-used.
             return local;
         }
 
         // Ditto. Returns true if a new RegisterID was added, false if a pre-existing RegisterID was re-used.

-        bool addVar(const Identifier&, bool isConstant, RegisterID*&);
+        bool addVar(const Identifier&, ConstantMode, WatchMode, RegisterID*&);

         
         // Adds an anonymous var slot. To give this slot a name, add it to symbolTable().
         RegisterID* addVar()
         
         // Adds an anonymous var slot. To give this slot a name, add it to symbolTable().
         RegisterID* addVar()


@@ -447,59 +520,54 @@ namespace JSC {
         }
 
         // Returns the index of the added var.
         }
 
         // Returns the index of the added var.

-        int addGlobalVar(const Identifier&, bool isConstant);
-

         void addParameter(const Identifier&, int parameterIndex);
         void addParameter(const Identifier&, int parameterIndex);

-        
+        RegisterID* resolveCallee(FunctionBodyNode*);
+        void addCallee(FunctionBodyNode*, RegisterID*);
+

         void preserveLastVar();
         void preserveLastVar();

-        bool shouldAvoidResolveGlobal();

 
         RegisterID& registerFor(int index)
         {
 
         RegisterID& registerFor(int index)
         {

-            if (index >= 0)
-                return m_calleeRegisters[index];
+            if (operandIsLocal(index))
+                return m_calleeRegisters[VirtualRegister(index).toLocal()];
+
+            if (index == JSStack::Callee)
+                return m_calleeRegister;

 
             ASSERT(m_parameters.size());
 
             ASSERT(m_parameters.size());

-            return m_parameters[index + m_parameters.size() + RegisterFile::CallFrameHeaderSize];
+            return m_parameters[VirtualRegister(index).toArgument()];

         }
 
         unsigned addConstant(const Identifier&);
         RegisterID* addConstantValue(JSValue);
         }
 
         unsigned addConstant(const Identifier&);
         RegisterID* addConstantValue(JSValue);

+        RegisterID* addConstantEmptyValue();

         unsigned addRegExp(RegExp*);
 
         unsigned addConstantBuffer(unsigned length);
         
         unsigned addRegExp(RegExp*);
 
         unsigned addConstantBuffer(unsigned length);
         

-        FunctionExecutable* makeFunction(ExecState* exec, FunctionBodyNode* body)
-        {
-            return FunctionExecutable::create(exec, body->ident(), body->inferredName(), body->source(), body->usesArguments(), body->parameters(), body->isStrictMode(), body->lineNo(), body->lastLine());
-        }
-
-        FunctionExecutable* makeFunction(JSGlobalData* globalData, FunctionBodyNode* body)
+        UnlinkedFunctionExecutable* makeFunction(FunctionBodyNode* body)

         {
         {

-            return FunctionExecutable::create(*globalData, body->ident(), body->inferredName(), body->source(), body->usesArguments(), body->parameters(), body->isStrictMode(), body->lineNo(), body->lastLine());
+            return UnlinkedFunctionExecutable::create(m_vm, m_scopeNode->source(), body, isBuiltinFunction() ? UnlinkedBuiltinFunction : UnlinkedNormalFunction);

         }
 
         }
 

+        RegisterID* emitInitLazyRegister(RegisterID*);
+        
+        RegisterID* emitConstructVarargs(RegisterID* dst, RegisterID* func, RegisterID* arguments, RegisterID* firstFreeRegister, int32_t firstVarArgOffset, RegisterID* profileHookRegister, const JSTextPosition& divot, const JSTextPosition& divotStart, const JSTextPosition& divotEnd);
+        RegisterID* emitCallVarargs(OpcodeID, RegisterID* dst, RegisterID* func, RegisterID* thisRegister, RegisterID* arguments, RegisterID* firstFreeRegister, int32_t firstVarArgOffset, RegisterID* profileHookRegister, const JSTextPosition& divot, const JSTextPosition& divotStart, const JSTextPosition& divotEnd);
+        
+    public:

         JSString* addStringConstant(const Identifier&);
 
         JSString* addStringConstant(const Identifier&);
 

-        void addLineInfo(unsigned lineNo)
-        {
-#if !ENABLE(OPCODE_SAMPLING)
-            if (m_shouldEmitRichSourceInfo)
-#endif
-                m_codeBlock->addLineInfo(instructions().size(), lineNo);
-        }
+        Vector<UnlinkedInstruction, 0, UnsafeVectorOverflow>& instructions() { return m_instructions; }

 
 

-        RegisterID* emitInitLazyRegister(RegisterID*);
-
-        Vector<Instruction>& instructions() { return m_instructions; }

         SymbolTable& symbolTable() { return *m_symbolTable; }
 
         bool shouldOptimizeLocals()
         {
         SymbolTable& symbolTable() { return *m_symbolTable; }
 
         bool shouldOptimizeLocals()
         {

-            if (m_dynamicScopeDepth)
+            if (m_codeType != FunctionCode)

                 return false;
 
                 return false;
 

-            if (m_codeType != FunctionCode)
+            if (m_localScopeDepth)

                 return false;
 
             return true;
                 return false;
 
             return true;


@@ -507,7 +575,7 @@ namespace JSC {
 
         bool canOptimizeNonLocals()
         {
 
         bool canOptimizeNonLocals()
         {

-            if (m_dynamicScopeDepth)
+            if (m_localScopeDepth)

                 return false;
 
             if (m_codeType == EvalCode)
                 return false;
 
             if (m_codeType == EvalCode)


@@ -519,44 +587,73 @@ namespace JSC {
             return true;
         }
 
             return true;
         }
 

+        bool shouldTearOffArgumentsEagerly()
+        {
+            return m_codeType == FunctionCode && isStrictMode() && m_scopeNode->modifiesParameter();
+        }
+

         RegisterID* emitThrowExpressionTooDeepException();
 
         void createArgumentsIfNecessary();
         void createActivationIfNecessary();
         RegisterID* createLazyRegisterIfNecessary(RegisterID*);
         
         RegisterID* emitThrowExpressionTooDeepException();
 
         void createArgumentsIfNecessary();
         void createActivationIfNecessary();
         RegisterID* createLazyRegisterIfNecessary(RegisterID*);
         

-        Vector<Instruction> m_instructions;
+        unsigned watchableVariable(int operand)
+        {
+            VirtualRegister reg(operand);
+            if (!reg.isLocal())
+                return UINT_MAX;
+            if (static_cast<size_t>(reg.toLocal()) >= m_watchableVariables.size())
+                return UINT_MAX;
+            Identifier& ident = m_watchableVariables[reg.toLocal()];
+            if (ident.isNull())
+                return UINT_MAX;
+            return addConstant(ident);
+        }
+        
+        bool hasWatchableVariable(int operand)
+        {
+            return watchableVariable(operand) != UINT_MAX;
+        }
+        
+        Vector<UnlinkedInstruction, 0, UnsafeVectorOverflow> m_instructions;

 
         bool m_shouldEmitDebugHooks;
         bool m_shouldEmitProfileHooks;
 
         bool m_shouldEmitDebugHooks;
         bool m_shouldEmitProfileHooks;

-        bool m_shouldEmitRichSourceInfo;

 
 

-        Strong<ScopeChainNode> m_scopeChain;

         SymbolTable* m_symbolTable;
 
         ScopeNode* m_scopeNode;
         SymbolTable* m_symbolTable;
 
         ScopeNode* m_scopeNode;

-        CodeBlock* m_codeBlock;
+        Strong<UnlinkedCodeBlock> m_codeBlock;

 
         // Some of these objects keep pointers to one another. They are arranged
         // to ensure a sane destruction order that avoids references to freed memory.
         HashSet<RefPtr<StringImpl>, IdentifierRepHash> m_functions;
         RegisterID m_ignoredResultRegister;
         RegisterID m_thisRegister;
 
         // Some of these objects keep pointers to one another. They are arranged
         // to ensure a sane destruction order that avoids references to freed memory.
         HashSet<RefPtr<StringImpl>, IdentifierRepHash> m_functions;
         RegisterID m_ignoredResultRegister;
         RegisterID m_thisRegister;

+        RegisterID m_calleeRegister;

         RegisterID* m_activationRegister;
         RegisterID* m_activationRegister;

+        RegisterID* m_emptyValueRegister;
+        RegisterID* m_globalObjectRegister;
+        Vector<Identifier, 16> m_watchableVariables;

         SegmentedVector<RegisterID, 32> m_constantPoolRegisters;
         SegmentedVector<RegisterID, 32> m_calleeRegisters;
         SegmentedVector<RegisterID, 32> m_parameters;
         SegmentedVector<Label, 32> m_labels;
         SegmentedVector<RegisterID, 32> m_constantPoolRegisters;
         SegmentedVector<RegisterID, 32> m_calleeRegisters;
         SegmentedVector<RegisterID, 32> m_parameters;
         SegmentedVector<Label, 32> m_labels;

-        SegmentedVector<LabelScope, 8> m_labelScopes;
+        LabelScopeStore m_labelScopes;

         RefPtr<RegisterID> m_lastVar;
         int m_finallyDepth;
         RefPtr<RegisterID> m_lastVar;
         int m_finallyDepth;

-        int m_dynamicScopeDepth;
-        int m_baseScopeDepth;
+        int m_localScopeDepth;

         CodeType m_codeType;
 
         CodeType m_codeType;
 

-        Vector<ControlFlowContext> m_scopeContextStack;
+        Vector<ControlFlowContext, 0, UnsafeVectorOverflow> m_scopeContextStack;

         Vector<SwitchInfo> m_switchContextStack;
         Vector<ForInContext> m_forInContextStack;
         Vector<SwitchInfo> m_switchContextStack;
         Vector<ForInContext> m_forInContextStack;

+        Vector<TryContext> m_tryContextStack;
+        Vector<std::pair<RefPtr<RegisterID>, const DeconstructionPatternNode*>> m_deconstructedParameters;
+        
+        Vector<TryRange> m_tryRanges;
+        SegmentedVector<TryData, 8> m_tryData;

 
         int m_firstConstantIndex;
         int m_nextConstantOffset;
 
         int m_firstConstantIndex;
         int m_nextConstantOffset;


@@ -564,10 +661,9 @@ namespace JSC {
 
         int m_globalVarStorageOffset;
 
 
         int m_globalVarStorageOffset;
 

-        bool m_hasCreatedActivation;

         int m_firstLazyFunction;
         int m_lastLazyFunction;
         int m_firstLazyFunction;
         int m_lastLazyFunction;

-        HashMap<unsigned int, FunctionBodyNode*, WTF::IntHash<unsigned int>, WTF::UnsignedWithZeroKeyHashTraits<unsigned int> > m_lazyFunctions;
+        HashMap<unsigned int, FunctionBodyNode*, WTF::IntHash<unsigned int>, WTF::UnsignedWithZeroKeyHashTraits<unsigned int>> m_lazyFunctions;

         typedef HashMap<FunctionBodyNode*, unsigned> FunctionOffsetMap;
         FunctionOffsetMap m_functionOffsets;
         
         typedef HashMap<FunctionBodyNode*, unsigned> FunctionOffsetMap;
         FunctionOffsetMap m_functionOffsets;
         


@@ -577,18 +673,20 @@ namespace JSC {
         NumberMap m_numberMap;
         IdentifierStringMap m_stringMap;
 
         NumberMap m_numberMap;
         IdentifierStringMap m_stringMap;
 

-        JSGlobalData* m_globalData;
+        StaticPropertyAnalyzer m_staticPropertyAnalyzer;
+
+        VM* m_vm;

 
         OpcodeID m_lastOpcodeID;
 #ifndef NDEBUG
         size_t m_lastOpcodePosition;
 #endif
 
 
         OpcodeID m_lastOpcodeID;
 #ifndef NDEBUG
         size_t m_lastOpcodePosition;
 #endif
 

-        StackBounds m_stack;
-

         bool m_usesExceptions;
         bool m_expressionTooDeep;
         bool m_usesExceptions;
         bool m_expressionTooDeep;

+        bool m_isBuiltinFunction;

     };
     };

+

 }
 
 #endif // BytecodeGenerator_h
 }
 
 #endif // BytecodeGenerator_h