Merge WebKit at r75315: Initial merge by git.

Change-Id: I570314b346ce101c935ed22a626b48c2af266b84

1 files changed, 647 insertions, 0 deletions

diff --git a/Source/JavaScriptCore/runtime/JSString.h b/Source/JavaScriptCore/runtime/JSString.h
new file mode 100644
index 0000000..fefffde
--- /dev/null
+++ b/Source/JavaScriptCore/runtime/JSString.h
@@ -0,0 +1,647 @@
+/*
+ *  Copyright (C) 1999-2001 Harri Porten (porten@kde.org)
+ *  Copyright (C) 2001 Peter Kelly (pmk@post.com)
+ *  Copyright (C) 2003, 2004, 2005, 2006, 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 JSString_h
+#define JSString_h
+
+#include "CallFrame.h"
+#include "CommonIdentifiers.h"
+#include "Identifier.h"
+#include "JSNumberCell.h"
+#include "PropertyDescriptor.h"
+#include "PropertySlot.h"
+#include "RopeImpl.h"
+
+namespace JSC {
+
+    class JSString;
+
+    JSString* jsEmptyString(JSGlobalData*);
+    JSString* jsEmptyString(ExecState*);
+    JSString* jsString(JSGlobalData*, const UString&); // returns empty string if passed null string
+    JSString* jsString(ExecState*, const UString&); // returns empty string if passed null string
+
+    JSString* jsSingleCharacterString(JSGlobalData*, UChar);
+    JSString* jsSingleCharacterString(ExecState*, UChar);
+    JSString* jsSingleCharacterSubstring(ExecState*, const UString&, unsigned offset);
+    JSString* jsSubstring(JSGlobalData*, const UString&, unsigned offset, unsigned length);
+    JSString* jsSubstring(ExecState*, const UString&, unsigned offset, unsigned length);
+
+    // Non-trivial strings are two or more characters long.
+    // These functions are faster than just calling jsString.
+    JSString* jsNontrivialString(JSGlobalData*, const UString&);
+    JSString* jsNontrivialString(ExecState*, const UString&);
+    JSString* jsNontrivialString(JSGlobalData*, const char*);
+    JSString* jsNontrivialString(ExecState*, const char*);
+
+    // Should be used for strings that are owned by an object that will
+    // likely outlive the JSValue this makes, such as the parse tree or a
+    // DOM object that contains a UString
+    JSString* jsOwnedString(JSGlobalData*, const UString&); 
+    JSString* jsOwnedString(ExecState*, const UString&); 
+
+    typedef void (*JSStringFinalizerCallback)(JSString*, void* context);
+    JSString* jsStringWithFinalizer(ExecState*, const UString&, JSStringFinalizerCallback callback, void* context);
+
+    class JS_EXPORTCLASS JSString : public JSCell {
+    public:
+        friend class JIT;
+        friend class JSGlobalData;
+        friend class SpecializedThunkJIT;
+        friend struct ThunkHelpers;
+
+        class RopeBuilder {
+        public:
+            RopeBuilder(unsigned fiberCount)
+                : m_index(0)
+                , m_rope(RopeImpl::tryCreateUninitialized(fiberCount))
+            {
+            }
+
+            bool isOutOfMemory() { return !m_rope; }
+
+            void append(RopeImpl::Fiber& fiber)
+            {
+                ASSERT(m_rope);
+                m_rope->initializeFiber(m_index, fiber);
+            }
+            void append(const UString& string)
+            {
+                ASSERT(m_rope);
+                m_rope->initializeFiber(m_index, string.impl());
+            }
+            void append(JSString* jsString)
+            {
+                if (jsString->isRope()) {
+                    for (unsigned i = 0; i < jsString->m_fiberCount; ++i)
+                        append(jsString->m_other.m_fibers[i]);
+                } else
+                    append(jsString->string());
+            }
+
+            PassRefPtr<RopeImpl> release()
+            {
+                ASSERT(m_index == m_rope->fiberCount());
+                return m_rope.release();
+            }
+
+            unsigned length() { return m_rope->length(); }
+
+        private:
+            unsigned m_index;
+            RefPtr<RopeImpl> m_rope;
+        };
+
+        class RopeIterator {
+            public:
+                RopeIterator() { }
+
+                RopeIterator(RopeImpl::Fiber* fibers, size_t fiberCount)
+                {
+                    ASSERT(fiberCount);
+                    m_workQueue.append(WorkItem(fibers, fiberCount));
+                    skipRopes();
+                }
+
+                RopeIterator& operator++()
+                {
+                    WorkItem& item = m_workQueue.last();
+                    ASSERT(!RopeImpl::isRope(item.fibers[item.i]));
+                    if (++item.i == item.fiberCount)
+                        m_workQueue.removeLast();
+                    skipRopes();
+                    return *this;
+                }
+
+                StringImpl* operator*()
+                {
+                    WorkItem& item = m_workQueue.last();
+                    RopeImpl::Fiber fiber = item.fibers[item.i];
+                    ASSERT(!RopeImpl::isRope(fiber));
+                    return static_cast<StringImpl*>(fiber);
+                }
+
+                bool operator!=(const RopeIterator& other) const
+                {
+                    return m_workQueue != other.m_workQueue;
+                }
+
+            private:
+                struct WorkItem {
+                    WorkItem(RopeImpl::Fiber* fibers, size_t fiberCount)
+                        : fibers(fibers)
+                        , fiberCount(fiberCount)
+                        , i(0)
+                    {
+                    }
+
+                    bool operator!=(const WorkItem& other) const
+                    {
+                        return fibers != other.fibers || fiberCount != other.fiberCount || i != other.i;
+                    }
+
+                    RopeImpl::Fiber* fibers;
+                    size_t fiberCount;
+                    size_t i;
+                };
+
+                void skipRopes()
+                {
+                    if (m_workQueue.isEmpty())
+                        return;
+
+                    while (1) {
+                        WorkItem& item = m_workQueue.last();
+                        RopeImpl::Fiber fiber = item.fibers[item.i];
+                        if (!RopeImpl::isRope(fiber))
+                            break;
+                        RopeImpl* rope = static_cast<RopeImpl*>(fiber);
+                        if (++item.i == item.fiberCount)
+                            m_workQueue.removeLast();
+                        m_workQueue.append(WorkItem(rope->fibers(), rope->fiberCount()));
+                    }
+                }
+
+                Vector<WorkItem, 16> m_workQueue;
+        };
+
+        ALWAYS_INLINE JSString(JSGlobalData* globalData, const UString& value)
+            : JSCell(globalData->stringStructure.get())
+            , m_length(value.length())
+            , m_value(value)
+            , m_fiberCount(0)
+        {
+            ASSERT(!m_value.isNull());
+            Heap::heap(this)->reportExtraMemoryCost(value.impl()->cost());
+        }
+
+        enum HasOtherOwnerType { HasOtherOwner };
+        JSString(JSGlobalData* globalData, const UString& value, HasOtherOwnerType)
+            : JSCell(globalData->stringStructure.get())
+            , m_length(value.length())
+            , m_value(value)
+            , m_fiberCount(0)
+        {
+            ASSERT(!m_value.isNull());
+        }
+        JSString(JSGlobalData* globalData, PassRefPtr<StringImpl> value, HasOtherOwnerType)
+            : JSCell(globalData->stringStructure.get())
+            , m_length(value->length())
+            , m_value(value)
+            , m_fiberCount(0)
+        {
+            ASSERT(!m_value.isNull());
+        }
+        JSString(JSGlobalData* globalData, PassRefPtr<RopeImpl> rope)
+            : JSCell(globalData->stringStructure.get())
+            , m_length(rope->length())
+            , m_fiberCount(1)
+        {
+            m_other.m_fibers[0] = rope.leakRef();
+        }
+        // This constructor constructs a new string by concatenating s1 & s2.
+        // This should only be called with fiberCount <= 3.
+        JSString(JSGlobalData* globalData, unsigned fiberCount, JSString* s1, JSString* s2)
+            : JSCell(globalData->stringStructure.get())
+            , m_length(s1->length() + s2->length())
+            , m_fiberCount(fiberCount)
+        {
+            ASSERT(fiberCount <= s_maxInternalRopeLength);
+            unsigned index = 0;
+            appendStringInConstruct(index, s1);
+            appendStringInConstruct(index, s2);
+            ASSERT(fiberCount == index);
+        }
+        // This constructor constructs a new string by concatenating s1 & s2.
+        // This should only be called with fiberCount <= 3.
+        JSString(JSGlobalData* globalData, unsigned fiberCount, JSString* s1, const UString& u2)
+            : JSCell(globalData->stringStructure.get())
+            , m_length(s1->length() + u2.length())
+            , m_fiberCount(fiberCount)
+        {
+            ASSERT(fiberCount <= s_maxInternalRopeLength);
+            unsigned index = 0;
+            appendStringInConstruct(index, s1);
+            appendStringInConstruct(index, u2);
+            ASSERT(fiberCount == index);
+        }
+        // This constructor constructs a new string by concatenating s1 & s2.
+        // This should only be called with fiberCount <= 3.
+        JSString(JSGlobalData* globalData, unsigned fiberCount, const UString& u1, JSString* s2)
+            : JSCell(globalData->stringStructure.get())
+            , m_length(u1.length() + s2->length())
+            , m_fiberCount(fiberCount)
+        {
+            ASSERT(fiberCount <= s_maxInternalRopeLength);
+            unsigned index = 0;
+            appendStringInConstruct(index, u1);
+            appendStringInConstruct(index, s2);
+            ASSERT(fiberCount == index);
+        }
+        // This constructor constructs a new string by concatenating v1, v2 & v3.
+        // This should only be called with fiberCount <= 3 ... which since every
+        // value must require a fiberCount of at least one implies that the length
+        // for each value must be exactly 1!
+        JSString(ExecState* exec, JSValue v1, JSValue v2, JSValue v3)
+            : JSCell(exec->globalData().stringStructure.get())
+            , m_length(0)
+            , m_fiberCount(s_maxInternalRopeLength)
+        {
+            unsigned index = 0;
+            appendValueInConstructAndIncrementLength(exec, index, v1);
+            appendValueInConstructAndIncrementLength(exec, index, v2);
+            appendValueInConstructAndIncrementLength(exec, index, v3);
+            ASSERT(index == s_maxInternalRopeLength);
+        }
+
+        // This constructor constructs a new string by concatenating u1 & u2.
+        JSString(JSGlobalData* globalData, const UString& u1, const UString& u2)
+            : JSCell(globalData->stringStructure.get())
+            , m_length(u1.length() + u2.length())
+            , m_fiberCount(2)
+        {
+            unsigned index = 0;
+            appendStringInConstruct(index, u1);
+            appendStringInConstruct(index, u2);
+            ASSERT(index <= s_maxInternalRopeLength);
+        }
+
+        // This constructor constructs a new string by concatenating u1, u2 & u3.
+        JSString(JSGlobalData* globalData, const UString& u1, const UString& u2, const UString& u3)
+            : JSCell(globalData->stringStructure.get())
+            , m_length(u1.length() + u2.length() + u3.length())
+            , m_fiberCount(s_maxInternalRopeLength)
+        {
+            unsigned index = 0;
+            appendStringInConstruct(index, u1);
+            appendStringInConstruct(index, u2);
+            appendStringInConstruct(index, u3);
+            ASSERT(index <= s_maxInternalRopeLength);
+        }
+
+        JSString(JSGlobalData* globalData, const UString& value, JSStringFinalizerCallback finalizer, void* context)
+            : JSCell(globalData->stringStructure.get())
+            , m_length(value.length())
+            , m_value(value)
+            , m_fiberCount(0)
+        {
+            ASSERT(!m_value.isNull());
+            // nasty hack because we can't union non-POD types
+            m_other.m_finalizerCallback = finalizer;
+            m_other.m_finalizerContext = context;
+            Heap::heap(this)->reportExtraMemoryCost(value.impl()->cost());
+        }
+
+        ~JSString()
+        {
+            ASSERT(vptr() == JSGlobalData::jsStringVPtr);
+            for (unsigned i = 0; i < m_fiberCount; ++i)
+                RopeImpl::deref(m_other.m_fibers[i]);
+
+            if (!m_fiberCount && m_other.m_finalizerCallback)
+                m_other.m_finalizerCallback(this, m_other.m_finalizerContext);
+        }
+
+        const UString& value(ExecState* exec) const
+        {
+            if (isRope())
+                resolveRope(exec);
+            return m_value;
+        }
+        const UString& tryGetValue() const
+        {
+            if (isRope())
+                resolveRope(0);
+            return m_value;
+        }
+        unsigned length() { return m_length; }
+
+        bool getStringPropertySlot(ExecState*, const Identifier& propertyName, PropertySlot&);
+        bool getStringPropertySlot(ExecState*, unsigned propertyName, PropertySlot&);
+        bool getStringPropertyDescriptor(ExecState*, const Identifier& propertyName, PropertyDescriptor&);
+
+        bool canGetIndex(unsigned i) { return i < m_length; }
+        JSString* getIndex(ExecState*, unsigned);
+        JSString* getIndexSlowCase(ExecState*, unsigned);
+
+        JSValue replaceCharacter(ExecState*, UChar, const UString& replacement);
+
+        static PassRefPtr<Structure> createStructure(JSValue proto) { return Structure::create(proto, TypeInfo(StringType, OverridesGetOwnPropertySlot | NeedsThisConversion), AnonymousSlotCount); }
+
+    private:
+        enum VPtrStealingHackType { VPtrStealingHack };
+        JSString(VPtrStealingHackType) 
+            : JSCell(0)
+            , m_fiberCount(0)
+        {
+        }
+
+        void resolveRope(ExecState*) const;
+        JSString* substringFromRope(ExecState*, unsigned offset, unsigned length);
+
+        void appendStringInConstruct(unsigned& index, const UString& string)
+        {
+            StringImpl* impl = string.impl();
+            impl->ref();
+            m_other.m_fibers[index++] = impl;
+        }
+
+        void appendStringInConstruct(unsigned& index, JSString* jsString)
+        {
+            if (jsString->isRope()) {
+                for (unsigned i = 0; i < jsString->m_fiberCount; ++i) {
+                    RopeImpl::Fiber fiber = jsString->m_other.m_fibers[i];
+                    fiber->ref();
+                    m_other.m_fibers[index++] = fiber;
+                }
+            } else
+                appendStringInConstruct(index, jsString->string());
+        }
+
+        void appendValueInConstructAndIncrementLength(ExecState* exec, unsigned& index, JSValue v)
+        {
+            if (v.isString()) {
+                ASSERT(v.asCell()->isString());
+                JSString* s = static_cast<JSString*>(v.asCell());
+                ASSERT(s->fiberCount() == 1);
+                appendStringInConstruct(index, s);
+                m_length += s->length();
+            } else {
+                UString u(v.toString(exec));
+                StringImpl* impl = u.impl();
+                impl->ref();
+                m_other.m_fibers[index++] = impl;
+                m_length += u.length();
+            }
+        }
+
+        virtual JSValue toPrimitive(ExecState*, PreferredPrimitiveType) const;
+        virtual bool getPrimitiveNumber(ExecState*, double& number, JSValue& value);
+        virtual bool toBoolean(ExecState*) const;
+        virtual double toNumber(ExecState*) const;
+        virtual JSObject* toObject(ExecState*) const;
+        virtual UString toString(ExecState*) const;
+
+        virtual JSObject* toThisObject(ExecState*) const;
+
+        // Actually getPropertySlot, not getOwnPropertySlot (see JSCell).
+        virtual bool getOwnPropertySlot(ExecState*, const Identifier& propertyName, PropertySlot&);
+        virtual bool getOwnPropertySlot(ExecState*, unsigned propertyName, PropertySlot&);
+        virtual bool getOwnPropertyDescriptor(ExecState*, const Identifier&, PropertyDescriptor&);
+
+        static const unsigned s_maxInternalRopeLength = 3;
+
+        // A string is represented either by a UString or a RopeImpl.
+        unsigned m_length;
+        mutable UString m_value;
+        mutable unsigned m_fiberCount;
+        // This structure exists to support a temporary workaround for a GC issue.
+        struct JSStringFinalizerStruct {
+            JSStringFinalizerStruct() : m_finalizerCallback(0) {}
+            union {
+                mutable FixedArray<RopeImpl::Fiber, s_maxInternalRopeLength> m_fibers;
+                struct {
+                    JSStringFinalizerCallback m_finalizerCallback;
+                    void* m_finalizerContext;
+                };
+            };
+        } m_other;
+
+        bool isRope() const { return m_fiberCount; }
+        UString& string() { ASSERT(!isRope()); return m_value; }
+        unsigned fiberCount() { return m_fiberCount ? m_fiberCount : 1; }
+
+        friend JSValue jsString(ExecState* exec, JSString* s1, JSString* s2);
+        friend JSValue jsString(ExecState* exec, const UString& u1, JSString* s2);
+        friend JSValue jsString(ExecState* exec, JSString* s1, const UString& u2);
+        friend JSValue jsString(ExecState* exec, Register* strings, unsigned count);
+        friend JSValue jsString(ExecState* exec, JSValue thisValue);
+        friend JSString* jsStringWithFinalizer(ExecState*, const UString&, JSStringFinalizerCallback callback, void* context);
+        friend JSString* jsSubstring(ExecState* exec, JSString* s, unsigned offset, unsigned length);
+    };
+
+    JSString* asString(JSValue);
+
+    // When an object is created from a different DLL, MSVC changes vptr to a "local" one right after invoking a constructor,
+    // see <http://groups.google.com/group/microsoft.public.vc.language/msg/55cdcefeaf770212>.
+    // This breaks isJSString(), and we don't need that hack anyway, so we change vptr back to primary one.
+    // The below function must be called by any inline function that invokes a JSString constructor.
+#if COMPILER(MSVC) && !defined(BUILDING_JavaScriptCore)
+    inline JSString* fixupVPtr(JSGlobalData* globalData, JSString* string) { string->setVPtr(globalData->jsStringVPtr); return string; }
+#else
+    inline JSString* fixupVPtr(JSGlobalData*, JSString* string) { return string; }
+#endif
+
+    inline JSString* asString(JSValue value)
+    {
+        ASSERT(value.asCell()->isString());
+        return static_cast<JSString*>(value.asCell());
+    }
+
+    inline JSString* jsEmptyString(JSGlobalData* globalData)
+    {
+        return globalData->smallStrings.emptyString(globalData);
+    }
+
+    inline JSString* jsSingleCharacterString(JSGlobalData* globalData, UChar c)
+    {
+        if (c <= 0xFF)
+            return globalData->smallStrings.singleCharacterString(globalData, c);
+        return fixupVPtr(globalData, new (globalData) JSString(globalData, UString(&c, 1)));
+    }
+
+    inline JSString* jsSingleCharacterSubstring(ExecState* exec, const UString& s, unsigned offset)
+    {
+        JSGlobalData* globalData = &exec->globalData();
+        ASSERT(offset < static_cast<unsigned>(s.length()));
+        UChar c = s.characters()[offset];
+        if (c <= 0xFF)
+            return globalData->smallStrings.singleCharacterString(globalData, c);
+        return fixupVPtr(globalData, new (globalData) JSString(globalData, UString(StringImpl::create(s.impl(), offset, 1))));
+    }
+
+    inline JSString* jsNontrivialString(JSGlobalData* globalData, const char* s)
+    {
+        ASSERT(s);
+        ASSERT(s[0]);
+        ASSERT(s[1]);
+        return fixupVPtr(globalData, new (globalData) JSString(globalData, s));
+    }
+
+    inline JSString* jsNontrivialString(JSGlobalData* globalData, const UString& s)
+    {
+        ASSERT(s.length() > 1);
+        return fixupVPtr(globalData, new (globalData) JSString(globalData, s));
+    }
+
+    inline JSString* JSString::getIndex(ExecState* exec, unsigned i)
+    {
+        ASSERT(canGetIndex(i));
+        if (isRope())
+            return getIndexSlowCase(exec, i);
+        ASSERT(i < m_value.length());
+        return jsSingleCharacterSubstring(exec, m_value, i);
+    }
+
+    inline JSString* jsString(JSGlobalData* globalData, const UString& s)
+    {
+        int size = s.length();
+        if (!size)
+            return globalData->smallStrings.emptyString(globalData);
+        if (size == 1) {
+            UChar c = s.characters()[0];
+            if (c <= 0xFF)
+                return globalData->smallStrings.singleCharacterString(globalData, c);
+        }
+        return fixupVPtr(globalData, new (globalData) JSString(globalData, s));
+    }
+
+    inline JSString* jsStringWithFinalizer(ExecState* exec, const UString& s, JSStringFinalizerCallback callback, void* context)
+    {
+        ASSERT(s.length() && (s.length() > 1 || s.characters()[0] > 0xFF));
+        JSGlobalData* globalData = &exec->globalData();
+        return fixupVPtr(globalData, new (globalData) JSString(globalData, s, callback, context));
+    }
+    
+    inline JSString* jsSubstring(ExecState* exec, JSString* s, unsigned offset, unsigned length)
+    {
+        ASSERT(offset <= static_cast<unsigned>(s->length()));
+        ASSERT(length <= static_cast<unsigned>(s->length()));
+        ASSERT(offset + length <= static_cast<unsigned>(s->length()));
+        JSGlobalData* globalData = &exec->globalData();
+        if (!length)
+            return globalData->smallStrings.emptyString(globalData);
+        if (s->isRope())
+            return s->substringFromRope(exec, offset, length);
+        return jsSubstring(globalData, s->m_value, offset, length);
+    }
+
+    inline JSString* jsSubstring(JSGlobalData* globalData, const UString& s, unsigned offset, unsigned length)
+    {
+        ASSERT(offset <= static_cast<unsigned>(s.length()));
+        ASSERT(length <= static_cast<unsigned>(s.length()));
+        ASSERT(offset + length <= static_cast<unsigned>(s.length()));
+        if (!length)
+            return globalData->smallStrings.emptyString(globalData);
+        if (length == 1) {
+            UChar c = s.characters()[offset];
+            if (c <= 0xFF)
+                return globalData->smallStrings.singleCharacterString(globalData, c);
+        }
+        return fixupVPtr(globalData, new (globalData) JSString(globalData, UString(StringImpl::create(s.impl(), offset, length)), JSString::HasOtherOwner));
+    }
+
+    inline JSString* jsOwnedString(JSGlobalData* globalData, const UString& s)
+    {
+        int size = s.length();
+        if (!size)
+            return globalData->smallStrings.emptyString(globalData);
+        if (size == 1) {
+            UChar c = s.characters()[0];
+            if (c <= 0xFF)
+                return globalData->smallStrings.singleCharacterString(globalData, c);
+        }
+        return fixupVPtr(globalData, new (globalData) JSString(globalData, s, JSString::HasOtherOwner));
+    }
+
+    inline JSString* jsEmptyString(ExecState* exec) { return jsEmptyString(&exec->globalData()); }
+    inline JSString* jsString(ExecState* exec, const UString& s) { return jsString(&exec->globalData(), s); }
+    inline JSString* jsSingleCharacterString(ExecState* exec, UChar c) { return jsSingleCharacterString(&exec->globalData(), c); }
+    inline JSString* jsSubstring(ExecState* exec, const UString& s, unsigned offset, unsigned length) { return jsSubstring(&exec->globalData(), s, offset, length); }
+    inline JSString* jsNontrivialString(ExecState* exec, const UString& s) { return jsNontrivialString(&exec->globalData(), s); }
+    inline JSString* jsNontrivialString(ExecState* exec, const char* s) { return jsNontrivialString(&exec->globalData(), s); }
+    inline JSString* jsOwnedString(ExecState* exec, const UString& s) { return jsOwnedString(&exec->globalData(), s); } 
+
+    ALWAYS_INLINE bool JSString::getStringPropertySlot(ExecState* exec, const Identifier& propertyName, PropertySlot& slot)
+    {
+        if (propertyName == exec->propertyNames().length) {
+            slot.setValue(jsNumber(m_length));
+            return true;
+        }
+
+        bool isStrictUInt32;
+        unsigned i = propertyName.toUInt32(isStrictUInt32);
+        if (isStrictUInt32 && i < m_length) {
+            slot.setValue(getIndex(exec, i));
+            return true;
+        }
+
+        return false;
+    }
+        
+    ALWAYS_INLINE bool JSString::getStringPropertySlot(ExecState* exec, unsigned propertyName, PropertySlot& slot)
+    {
+        if (propertyName < m_length) {
+            slot.setValue(getIndex(exec, propertyName));
+            return true;
+        }
+
+        return false;
+    }
+
+    inline bool isJSString(JSGlobalData* globalData, JSValue v) { return v.isCell() && v.asCell()->vptr() == globalData->jsStringVPtr; }
+
+    // --- JSValue inlines ----------------------------
+
+    inline UString JSValue::toString(ExecState* exec) const
+    {
+        if (isString())
+            return static_cast<JSString*>(asCell())->value(exec);
+        if (isInt32())
+            return exec->globalData().numericStrings.add(asInt32());
+        if (isDouble())
+            return exec->globalData().numericStrings.add(asDouble());
+        if (isTrue())
+            return "true";
+        if (isFalse())
+            return "false";
+        if (isNull())
+            return "null";
+        if (isUndefined())
+            return "undefined";
+        ASSERT(isCell());
+        return asCell()->toString(exec);
+    }
+
+    inline UString JSValue::toPrimitiveString(ExecState* exec) const
+    {
+        if (isString())
+            return static_cast<JSString*>(asCell())->value(exec);
+        if (isInt32())
+            return exec->globalData().numericStrings.add(asInt32());
+        if (isDouble())
+            return exec->globalData().numericStrings.add(asDouble());
+        if (isTrue())
+            return "true";
+        if (isFalse())
+            return "false";
+        if (isNull())
+            return "null";
+        if (isUndefined())
+            return "undefined";
+        ASSERT(isCell());
+        return asCell()->toPrimitive(exec, NoPreference).toString(exec);
+    }
+
+} // namespace JSC
+
+#endif // JSString_h