diff -r 000000000000 -r 1918ee327afb src/3rdparty/webkit/JavaScriptCore/runtime/Identifier.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/3rdparty/webkit/JavaScriptCore/runtime/Identifier.cpp	Mon Jan 11 14:00:40 2010 +0000
@@ -0,0 +1,268 @@
+/*
+ *  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.
+ *
+ */
+
+#include "config.h"
+#include "Identifier.h"
+
+#include "CallFrame.h"
+#include <new> // for placement new
+#include <string.h> // for strlen
+#include <wtf/Assertions.h>
+#include <wtf/FastMalloc.h>
+#include <wtf/HashSet.h>
+
+namespace JSC {
+
+typedef HashMap<const char*, RefPtr<UString::Rep>, PtrHash<const char*> > LiteralIdentifierTable;
+
+class IdentifierTable : public FastAllocBase {
+public:
+    ~IdentifierTable()
+    {
+        HashSet<UString::Rep*>::iterator end = m_table.end();
+        for (HashSet<UString::Rep*>::iterator iter = m_table.begin(); iter != end; ++iter)
+            (*iter)->setIdentifierTable(0);
+    }
+    
+    std::pair<HashSet<UString::Rep*>::iterator, bool> add(UString::Rep* value)
+    {
+        std::pair<HashSet<UString::Rep*>::iterator, bool> result = m_table.add(value);
+        (*result.first)->setIdentifierTable(this);
+        return result;
+    }
+
+    template<typename U, typename V>
+    std::pair<HashSet<UString::Rep*>::iterator, bool> add(U value)
+    {
+        std::pair<HashSet<UString::Rep*>::iterator, bool> result = m_table.add<U, V>(value);
+        (*result.first)->setIdentifierTable(this);
+        return result;
+    }
+
+    void remove(UString::Rep* r) { m_table.remove(r); }
+
+    LiteralIdentifierTable& literalTable() { return m_literalTable; }
+
+private:
+    HashSet<UString::Rep*> m_table;
+    LiteralIdentifierTable m_literalTable;
+};
+
+IdentifierTable* createIdentifierTable()
+{
+    return new IdentifierTable;
+}
+
+void deleteIdentifierTable(IdentifierTable* table)
+{
+    delete table;
+}
+
+bool Identifier::equal(const UString::Rep* r, const char* s)
+{
+    int length = r->len;
+    const UChar* d = r->data();
+    for (int i = 0; i != length; ++i)
+        if (d[i] != (unsigned char)s[i])
+            return false;
+    return s[length] == 0;
+}
+
+bool Identifier::equal(const UString::Rep* r, const UChar* s, int length)
+{
+    if (r->len != length)
+        return false;
+    const UChar* d = r->data();
+    for (int i = 0; i != length; ++i)
+        if (d[i] != s[i])
+            return false;
+    return true;
+}
+
+struct CStringTranslator {
+    static unsigned hash(const char* c)
+    {
+        return UString::Rep::computeHash(c);
+    }
+
+    static bool equal(UString::Rep* r, const char* s)
+    {
+        return Identifier::equal(r, s);
+    }
+
+    static void translate(UString::Rep*& location, const char* c, unsigned hash)
+    {
+        size_t length = strlen(c);
+        UChar* d = static_cast<UChar*>(fastMalloc(sizeof(UChar) * length));
+        for (size_t i = 0; i != length; i++)
+            d[i] = static_cast<unsigned char>(c[i]); // use unsigned char to zero-extend instead of sign-extend
+        
+        UString::Rep* r = UString::Rep::create(d, static_cast<int>(length)).releaseRef();
+        r->_hash = hash;
+
+        location = r;
+    }
+};
+
+PassRefPtr<UString::Rep> Identifier::add(JSGlobalData* globalData, const char* c)
+{
+    if (!c) {
+        UString::Rep::null().hash();
+        return &UString::Rep::null();
+    }
+    if (!c[0]) {
+        UString::Rep::empty().hash();
+        return &UString::Rep::empty();
+    }
+    if (!c[1])
+        return add(globalData, globalData->smallStrings.singleCharacterStringRep(static_cast<unsigned char>(c[0])));
+
+    IdentifierTable& identifierTable = *globalData->identifierTable;
+    LiteralIdentifierTable& literalIdentifierTable = identifierTable.literalTable();
+
+    const LiteralIdentifierTable::iterator& iter = literalIdentifierTable.find(c);
+    if (iter != literalIdentifierTable.end())
+        return iter->second;
+
+    pair<HashSet<UString::Rep*>::iterator, bool> addResult = identifierTable.add<const char*, CStringTranslator>(c);
+
+    // If the string is newly-translated, then we need to adopt it.
+    // The boolean in the pair tells us if that is so.
+    RefPtr<UString::Rep> addedString = addResult.second ? adoptRef(*addResult.first) : *addResult.first;
+
+    literalIdentifierTable.add(c, addedString.get());
+
+    return addedString.release();
+}
+
+PassRefPtr<UString::Rep> Identifier::add(ExecState* exec, const char* c)
+{
+    return add(&exec->globalData(), c);
+}
+
+struct UCharBuffer {
+    const UChar* s;
+    unsigned int length;
+};
+
+struct UCharBufferTranslator {
+    static unsigned hash(const UCharBuffer& buf)
+    {
+        return UString::Rep::computeHash(buf.s, buf.length);
+    }
+
+    static bool equal(UString::Rep* str, const UCharBuffer& buf)
+    {
+        return Identifier::equal(str, buf.s, buf.length);
+    }
+
+    static void translate(UString::Rep*& location, const UCharBuffer& buf, unsigned hash)
+    {
+        UChar* d = static_cast<UChar*>(fastMalloc(sizeof(UChar) * buf.length));
+        for (unsigned i = 0; i != buf.length; i++)
+            d[i] = buf.s[i];
+        
+        UString::Rep* r = UString::Rep::create(d, buf.length).releaseRef();
+        r->_hash = hash;
+        
+        location = r; 
+    }
+};
+
+PassRefPtr<UString::Rep> Identifier::add(JSGlobalData* globalData, const UChar* s, int length)
+{
+    if (length == 1) {
+        UChar c = s[0];
+        if (c <= 0xFF)
+            return add(globalData, globalData->smallStrings.singleCharacterStringRep(c));
+    }
+    if (!length) {
+        UString::Rep::empty().hash();
+        return &UString::Rep::empty();
+    }
+    UCharBuffer buf = {s, length}; 
+    pair<HashSet<UString::Rep*>::iterator, bool> addResult = globalData->identifierTable->add<UCharBuffer, UCharBufferTranslator>(buf);
+
+    // If the string is newly-translated, then we need to adopt it.
+    // The boolean in the pair tells us if that is so.
+    return addResult.second ? adoptRef(*addResult.first) : *addResult.first;
+}
+
+PassRefPtr<UString::Rep> Identifier::add(ExecState* exec, const UChar* s, int length)
+{
+    return add(&exec->globalData(), s, length);
+}
+
+PassRefPtr<UString::Rep> Identifier::addSlowCase(JSGlobalData* globalData, UString::Rep* r)
+{
+    ASSERT(!r->identifierTable());
+    if (r->len == 1) {
+        UChar c = r->data()[0];
+        if (c <= 0xFF)
+            r = globalData->smallStrings.singleCharacterStringRep(c);
+            if (r->identifierTable()) {
+#ifndef NDEBUG
+                checkSameIdentifierTable(globalData, r);
+#endif
+                return r;
+            }
+    }
+    if (!r->len) {
+        UString::Rep::empty().hash();
+        return &UString::Rep::empty();
+    }
+    return *globalData->identifierTable->add(r).first;
+}
+
+PassRefPtr<UString::Rep> Identifier::addSlowCase(ExecState* exec, UString::Rep* r)
+{
+    return addSlowCase(&exec->globalData(), r);
+}
+
+void Identifier::remove(UString::Rep* r)
+{
+    r->identifierTable()->remove(r);
+}
+
+#ifndef NDEBUG
+
+void Identifier::checkSameIdentifierTable(ExecState* exec, UString::Rep* rep)
+{
+    ASSERT(rep->identifierTable() == exec->globalData().identifierTable);
+}
+
+void Identifier::checkSameIdentifierTable(JSGlobalData* globalData, UString::Rep* rep)
+{
+    ASSERT(rep->identifierTable() == globalData->identifierTable);
+}
+
+#else
+
+void Identifier::checkSameIdentifierTable(ExecState*, UString::Rep*)
+{
+}
+
+void Identifier::checkSameIdentifierTable(JSGlobalData*, UString::Rep*)
+{
+}
+
+#endif
+
+} // namespace JSC