diff --git a/JavaScriptCore/interpreter/CallFrame.h b/JavaScriptCore/interpreter/CallFrame.h
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+++ b/JavaScriptCore/interpreter/CallFrame.h
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+/*
+ *  Copyright (C) 1999-2001 Harri Porten (porten@kde.org)
+ *  Copyright (C) 2001 Peter Kelly (pmk@post.com)
+ *  Copyright (C) 2003, 2007, 2008 Apple Inc. All rights reserved.
+ *
+ *  This library is free software; you can redistribute it and/or
+ *  modify it under the terms of the GNU Library General Public
+ *  License as published by the Free Software Foundation; either
+ *  version 2 of the License, or (at your option) any later version.
+ *
+ *  This library is distributed in the hope that it will be useful,
+ *  but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ *  Library General Public License for more details.
+ *
+ *  You should have received a copy of the GNU Library General Public License
+ *  along with this library; see the file COPYING.LIB.  If not, write to
+ *  the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+ *  Boston, MA 02110-1301, USA.
+ *
+ */
+
+#ifndef CallFrame_h
+#define CallFrame_h
+
+#include "JSGlobalData.h"
+#include "RegisterFile.h"
+#include "ScopeChain.h"
+
+namespace JSC  {
+
+    class Arguments;
+    class JSActivation;
+    class Interpreter;
+
+    // Represents the current state of script execution.
+    // Passed as the first argument to most functions.
+    class ExecState : private Register {
+    public:
+        JSFunction* callee() const { return this[RegisterFile::Callee].function(); }
+        CodeBlock* codeBlock() const { return this[RegisterFile::CodeBlock].Register::codeBlock(); }
+        ScopeChainNode* scopeChain() const { return this[RegisterFile::ScopeChain].Register::scopeChain(); }
+
+        JSValue* thisValue();
+
+        // Global object in which execution began.
+        JSGlobalObject* dynamicGlobalObject();
+
+        // Global object in which the currently executing code was defined.
+        // Differs from dynamicGlobalObject() during function calls across web browser frames.
+        JSGlobalObject* lexicalGlobalObject() const
+        {
+            return scopeChain()->globalObject();
+        }
+
+        // Differs from lexicalGlobalObject because this will have DOM window shell rather than
+        // the actual DOM window, which can't be "this" for security reasons.
+        JSObject* globalThisValue() const
+        {
+            return scopeChain()->globalThisObject();
+        }
+
+        // FIXME: Elsewhere, we use JSGlobalData* rather than JSGlobalData&.
+        // We should make this more uniform and either use a reference everywhere
+        // or a pointer everywhere.
+        JSGlobalData& globalData() const
+        {
+            return *scopeChain()->globalData;
+        }
+
+        // Convenience functions for access to global data.
+        // It takes a few memory references to get from a call frame to the global data
+        // pointer, so these are inefficient, and should be used sparingly in new code.
+        // But they're used in many places in legacy code, so they're not going away any time soon.
+
+        void setException(JSValue* exception) { globalData().exception = exception; }
+        void clearException() { globalData().exception = noValue(); }
+        JSValue* exception() const { return globalData().exception; }
+        JSValue** exceptionSlot() { return &globalData().exception; }
+        bool hadException() const { return !!globalData().exception; }
+
+        const CommonIdentifiers& propertyNames() const { return *globalData().propertyNames; }
+        const ArgList& emptyList() const { return *globalData().emptyList; }
+        Interpreter* interpreter() { return globalData().interpreter; }
+        Heap* heap() { return &globalData().heap; }
+
+        static const HashTable* arrayTable(CallFrame* callFrame) { return callFrame->globalData().arrayTable; }
+        static const HashTable* dateTable(CallFrame* callFrame) { return callFrame->globalData().dateTable; }
+        static const HashTable* mathTable(CallFrame* callFrame) { return callFrame->globalData().mathTable; }
+        static const HashTable* numberTable(CallFrame* callFrame) { return callFrame->globalData().numberTable; }
+        static const HashTable* regExpTable(CallFrame* callFrame) { return callFrame->globalData().regExpTable; }
+        static const HashTable* regExpConstructorTable(CallFrame* callFrame) { return callFrame->globalData().regExpConstructorTable; }
+        static const HashTable* stringTable(CallFrame* callFrame) { return callFrame->globalData().stringTable; }
+
+    private:
+        friend class Arguments;
+        friend class JSActivation;
+        friend class JSGlobalObject;
+        friend class Interpreter;
+
+        static CallFrame* create(Register* callFrameBase) { return static_cast<CallFrame*>(callFrameBase); }
+        Register* registers() { return this; }
+
+        CallFrame& operator=(const Register& r) { *static_cast<Register*>(this) = r; return *this; }
+
+        int argumentCount() const { return this[RegisterFile::ArgumentCount].i(); }
+        CallFrame* callerFrame() const { return this[RegisterFile::CallerFrame].callFrame(); }
+        Arguments* optionalCalleeArguments() const { return this[RegisterFile::OptionalCalleeArguments].arguments(); }
+        Instruction* returnPC() const { return this[RegisterFile::ReturnPC].vPC(); }
+        int returnValueRegister() const { return this[RegisterFile::ReturnValueRegister].i(); }
+
+        void setArgumentCount(int count) { this[RegisterFile::ArgumentCount] = count; }
+        void setCallee(JSFunction* callee) { this[RegisterFile::Callee] = callee; }
+        void setCalleeArguments(Arguments* arguments) { this[RegisterFile::OptionalCalleeArguments] = arguments; }
+        void setCallerFrame(CallFrame* callerFrame) { this[RegisterFile::CallerFrame] = callerFrame; }
+        void setCodeBlock(CodeBlock* codeBlock) { this[RegisterFile::CodeBlock] = codeBlock; }
+        void setScopeChain(ScopeChainNode* scopeChain) { this[RegisterFile::ScopeChain] = scopeChain; }
+
+        ALWAYS_INLINE void init(CodeBlock* codeBlock, Instruction* vPC, ScopeChainNode* scopeChain,
+            CallFrame* callerFrame, int returnValueRegister, int argc, JSFunction* function)
+        {
+            ASSERT(callerFrame); // Use noCaller() rather than 0 for the outer host call frame caller.
+
+            setCodeBlock(codeBlock);
+            setScopeChain(scopeChain);
+            setCallerFrame(callerFrame);
+            this[RegisterFile::ReturnPC] = vPC;
+            this[RegisterFile::ReturnValueRegister] = returnValueRegister;
+            setArgumentCount(argc); // original argument count (for the sake of the "arguments" object)
+            setCallee(function);
+            setCalleeArguments(0);
+        }
+
+        static const intptr_t HostCallFrameFlag = 1;
+
+        static CallFrame* noCaller() { return reinterpret_cast<CallFrame*>(HostCallFrameFlag); }
+        bool hasHostCallFrameFlag() const { return reinterpret_cast<intptr_t>(this) & HostCallFrameFlag; }
+        CallFrame* addHostCallFrameFlag() const { return reinterpret_cast<CallFrame*>(reinterpret_cast<intptr_t>(this) | HostCallFrameFlag); }
+        CallFrame* removeHostCallFrameFlag() { return reinterpret_cast<CallFrame*>(reinterpret_cast<intptr_t>(this) & ~HostCallFrameFlag); }
+
+        ExecState();
+        ~ExecState();
+    };
+
+} // namespace JSC
+
+#endif // CallFrame_h