Update src/3rdparty/javascriptcore and adapt src/script to the changes

- Update qscriptvalueiterator test to expect length property when
  iterating arrays and strings.

- Use EvalExecutable::create() instead of EvalExecutable constructor.
  The constructor is private.

- Reimplement getOwnPropertyDescriptor() in all custom script objects.

- Remove all reimplementations of getPropertyAttributes().
  It doesn't exist in trunk anymore (getOwnPropertyDescriptor() is used
  instead).

- Remove checkDontDelete argument from deleteProperty() reimplementations.
  The purpose of this argument was to support deleting properties
  with attribute Undeletable from C++. But it was quite an invasive
  patch to JavaScriptCore, and it doesn't seem worth it. If this feature
  is really crucial it should be re-done upstream.
  One of the tests needed to be updated so it's not sensitive to the
  C++ undeletability.

- Adapt getOwnPropertyNames() reimplementations to signature change.

- Add missing QScriptObject structure flags, otherwise we don't get all virtual calls.

- Remove our patch for reporting column numbers in the debugger callbacks.
  It was just too intrusive. As with the checkDontDelete issue, this should
  be redone upstream if it's really important. In 4.7, QScriptEngineAgent
  will always report a column number of 1.

Other compilation fixes:

- InternalFunction::name() takes an ExecState* argument, not GlobalData*
- ScopeChain::globalObject is no longer a function but a member variable
- ScopeChainNode constructor takes a GlobalObject argument
- Heap::collect() is called collectAllGarbage()
- JSValue::strictEqual() takes an ExecState* argument
- Debugger::exception() takes a bool hasHandler argument
- Debugger no longer reports column number (we decided to drop that patch from JSC)
- UString doesn't have operator+=(char*)

- Update the autotests to reflect the columnNumber=1 change.

- Add helper class to avoid crashing inside JSC.
  Ever since r52856 in WebKit trunk, this is needed. There are probably a lot of
  other public API functions that need this guard as well, but I'll add them as they
  are discovered.

- Update mkdist-javascriptcore tag, exclude a few more files.

- Set ENABLE_JSC_MULTIPLE_THREADS=0 define on Mac due to r52355 in trunk.

Reviewed-by: Simon Hausmann

18 files changed, 384 insertions, 231 deletions

diff --git a/src/3rdparty/javascriptcore/JavaScriptCore/API/APICast.h b/src/3rdparty/javascriptcore/JavaScriptCore/API/APICast.h
index b6d1532..4284c44 100644
--- a/src/3rdparty/javascriptcore/JavaScriptCore/API/APICast.h
+++ b/src/3rdparty/javascriptcore/JavaScriptCore/API/APICast.h
@@ -27,6 +27,7 @@
 #define APICast_h
 
 #include "JSAPIValueWrapper.h"
+#include "JSGlobalObject.h"
 #include "JSValue.h"
 #include <wtf/Platform.h>
 #include <wtf/UnusedParam.h>
@@ -50,16 +51,20 @@ typedef struct OpaqueJSValue* JSObjectRef;
 
 inline JSC::ExecState* toJS(JSContextRef c)
 {
+    ASSERT(c);
     return reinterpret_cast<JSC::ExecState*>(const_cast<OpaqueJSContext*>(c));
 }
 
 inline JSC::ExecState* toJS(JSGlobalContextRef c)
 {
+    ASSERT(c);
     return reinterpret_cast<JSC::ExecState*>(c);
 }
 
-inline JSC::JSValue toJS(JSC::ExecState*, JSValueRef v)
+inline JSC::JSValue toJS(JSC::ExecState* exec, JSValueRef v)
 {
+    ASSERT_UNUSED(exec, exec);
+    ASSERT(v);
 #if USE(JSVALUE32_64)
     JSC::JSCell* jsCell = reinterpret_cast<JSC::JSCell*>(const_cast<OpaqueJSValue*>(v));
     if (!jsCell)
@@ -72,6 +77,20 @@ inline JSC::JSValue toJS(JSC::ExecState*, JSValueRef v)
 #endif
 }
 
+inline JSC::JSValue toJSForGC(JSC::ExecState* exec, JSValueRef v)
+{
+    ASSERT_UNUSED(exec, exec);
+    ASSERT(v);
+#if USE(JSVALUE32_64)
+    JSC::JSCell* jsCell = reinterpret_cast<JSC::JSCell*>(const_cast<OpaqueJSValue*>(v));
+    if (!jsCell)
+        return JSC::JSValue();
+    return jsCell;
+#else
+    return JSC::JSValue::decode(reinterpret_cast<JSC::EncodedJSValue>(const_cast<OpaqueJSValue*>(v)));
+#endif
+}
+
 inline JSC::JSObject* toJS(JSObjectRef o)
 {
     return reinterpret_cast<JSC::JSObject*>(o);
@@ -118,6 +137,7 @@ inline JSContextRef toRef(JSC::ExecState* e)
 
 inline JSGlobalContextRef toGlobalRef(JSC::ExecState* e)
 {
+    ASSERT(e == e->lexicalGlobalObject()->globalExec());
     return reinterpret_cast<JSGlobalContextRef>(e);
 }
 
diff --git a/src/3rdparty/javascriptcore/JavaScriptCore/API/APIShims.h b/src/3rdparty/javascriptcore/JavaScriptCore/API/APIShims.h
new file mode 100644
index 0000000..f809d5d
--- /dev/null
+++ b/src/3rdparty/javascriptcore/JavaScriptCore/API/APIShims.h
@@ -0,0 +1,99 @@
+/*
+ * Copyright (C) 2009 Apple Inc. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
+ */
+
+#ifndef APIShims_h
+#define APIShims_h
+
+#include "CallFrame.h"
+#include "JSLock.h"
+
+namespace JSC {
+
+class APIEntryShimWithoutLock {
+protected:
+    APIEntryShimWithoutLock(JSGlobalData* globalData, bool registerThread)
+        : m_globalData(globalData)
+        , m_entryIdentifierTable(setCurrentIdentifierTable(globalData->identifierTable))
+    {
+        if (registerThread)
+            globalData->heap.registerThread();
+        m_globalData->timeoutChecker->start();
+    }
+
+    ~APIEntryShimWithoutLock()
+    {
+        m_globalData->timeoutChecker->stop();
+        setCurrentIdentifierTable(m_entryIdentifierTable);
+    }
+
+private:
+    JSGlobalData* m_globalData;
+    IdentifierTable* m_entryIdentifierTable;
+};
+
+class APIEntryShim : public APIEntryShimWithoutLock {
+public:
+    // Normal API entry
+    APIEntryShim(ExecState* exec, bool registerThread = true)
+        : APIEntryShimWithoutLock(&exec->globalData(), registerThread)
+        , m_lock(exec)
+    {
+    }
+
+    // JSPropertyNameAccumulator only has a globalData.
+    APIEntryShim(JSGlobalData* globalData, bool registerThread = true)
+        : APIEntryShimWithoutLock(globalData, registerThread)
+        , m_lock(globalData->isSharedInstance ? LockForReal : SilenceAssertionsOnly)
+    {
+    }
+
+private:
+    JSLock m_lock;
+};
+
+class APICallbackShim {
+public:
+    APICallbackShim(ExecState* exec)
+        : m_dropAllLocks(exec)
+        , m_globalData(&exec->globalData())
+    {
+        resetCurrentIdentifierTable();
+        m_globalData->timeoutChecker->start();
+    }
+
+    ~APICallbackShim()
+    {
+        m_globalData->timeoutChecker->stop();
+        setCurrentIdentifierTable(m_globalData->identifierTable);
+    }
+
+private:
+    JSLock::DropAllLocks m_dropAllLocks;
+    JSGlobalData* m_globalData;
+};
+
+}
+
+#endif
diff --git a/src/3rdparty/javascriptcore/JavaScriptCore/API/JSBase.cpp b/src/3rdparty/javascriptcore/JavaScriptCore/API/JSBase.cpp
index 4a32d35..ebfeafa 100644
--- a/src/3rdparty/javascriptcore/JavaScriptCore/API/JSBase.cpp
+++ b/src/3rdparty/javascriptcore/JavaScriptCore/API/JSBase.cpp
@@ -28,6 +28,7 @@
 #include "JSBasePrivate.h"
 
 #include "APICast.h"
+#include "APIShims.h"
 #include "Completion.h"
 #include "OpaqueJSString.h"
 #include "SourceCode.h"
@@ -43,8 +44,7 @@ using namespace JSC;
 JSValueRef JSEvaluateScript(JSContextRef ctx, JSStringRef script, JSObjectRef thisObject, JSStringRef sourceURL, int startingLineNumber, JSValueRef* exception)
 {
     ExecState* exec = toJS(ctx);
-    exec->globalData().heap.registerThread();
-    JSLock lock(exec);
+    APIEntryShim entryShim(exec);
 
     JSObject* jsThisObject = toJS(thisObject);
 
@@ -69,8 +69,7 @@ JSValueRef JSEvaluateScript(JSContextRef ctx, JSStringRef script, JSObjectRef th
 bool JSCheckScriptSyntax(JSContextRef ctx, JSStringRef script, JSStringRef sourceURL, int startingLineNumber, JSValueRef* exception)
 {
     ExecState* exec = toJS(ctx);
-    exec->globalData().heap.registerThread();
-    JSLock lock(exec);
+    APIEntryShim entryShim(exec);
 
     SourceCode source = makeSource(script->ustring(), sourceURL->ustring(), startingLineNumber);
     Completion completion = checkSyntax(exec->dynamicGlobalObject()->globalExec(), source);
@@ -94,12 +93,11 @@ void JSGarbageCollect(JSContextRef ctx)
         return;
 
     ExecState* exec = toJS(ctx);
-    JSGlobalData& globalData = exec->globalData();
-
-    JSLock lock(globalData.isSharedInstance ? LockForReal : SilenceAssertionsOnly);
+    APIEntryShim entryShim(exec, false);
 
+    JSGlobalData& globalData = exec->globalData();
     if (!globalData.heap.isBusy())
-        globalData.heap.collect();
+        globalData.heap.collectAllGarbage();
 
     // FIXME: Perhaps we should trigger a second mark and sweep
     // once the garbage collector is done if this is called when
@@ -109,8 +107,6 @@ void JSGarbageCollect(JSContextRef ctx)
 void JSReportExtraMemoryCost(JSContextRef ctx, size_t size)
 {
     ExecState* exec = toJS(ctx);
-    exec->globalData().heap.registerThread();
-    JSLock lock(exec);
-
+    APIEntryShim entryShim(exec);
     exec->globalData().heap.reportExtraMemoryCost(size);
 }
diff --git a/src/3rdparty/javascriptcore/JavaScriptCore/API/JSBase.h b/src/3rdparty/javascriptcore/JavaScriptCore/API/JSBase.h
index 0a0dcda..2e16720 100644
--- a/src/3rdparty/javascriptcore/JavaScriptCore/API/JSBase.h
+++ b/src/3rdparty/javascriptcore/JavaScriptCore/API/JSBase.h
@@ -64,33 +64,20 @@ typedef struct OpaqueJSValue* JSObjectRef;
 
 /* JavaScript symbol exports */
 
-#if !defined(JS_EXPORT)
-#if defined(BUILDING_WX__)
+#undef JS_EXPORT
+#if defined(JS_NO_EXPORT)
     #define JS_EXPORT
 #elif defined(__GNUC__) && !defined(__CC_ARM) && !defined(__ARMCC__)
     #define JS_EXPORT __attribute__((visibility("default")))
-#elif defined(_WIN32_WCE)
-    #if defined(JS_BUILDING_JS)
-        #define JS_EXPORT __declspec(dllexport)
-    #elif defined(JS_IMPORT_JS)
-        #define JS_EXPORT __declspec(dllimport)
-    #else
-        #define JS_EXPORT
-    #endif
-#elif defined(WIN32) || defined(_WIN32)
-    /*
-     * TODO: Export symbols with JS_EXPORT when using MSVC.
-     * See http://bugs.webkit.org/show_bug.cgi?id=16227
-     */
+#elif defined(WIN32) || defined(_WIN32) || defined(_WIN32_WCE)
     #if defined(BUILDING_JavaScriptCore) || defined(BUILDING_WTF)
-    #define JS_EXPORT __declspec(dllexport)
+        #define JS_EXPORT __declspec(dllexport)
     #else
-    #define JS_EXPORT __declspec(dllimport)
+        #define JS_EXPORT __declspec(dllimport)
     #endif
 #else
     #define JS_EXPORT
 #endif
-#endif
 
 #ifdef __cplusplus
 extern "C" {
diff --git a/src/3rdparty/javascriptcore/JavaScriptCore/API/JSCallbackConstructor.cpp b/src/3rdparty/javascriptcore/JavaScriptCore/API/JSCallbackConstructor.cpp
index 64c83cb..9c5f6d7 100644
--- a/src/3rdparty/javascriptcore/JavaScriptCore/API/JSCallbackConstructor.cpp
+++ b/src/3rdparty/javascriptcore/JavaScriptCore/API/JSCallbackConstructor.cpp
@@ -26,6 +26,7 @@
 #include "config.h"
 #include "JSCallbackConstructor.h"
 
+#include "APIShims.h"
 #include "APICast.h"
 #include <runtime/JSGlobalObject.h>
 #include <runtime/JSLock.h>
@@ -36,7 +37,7 @@ namespace JSC {
 
 const ClassInfo JSCallbackConstructor::info = { "CallbackConstructor", 0, 0, 0 };
 
-JSCallbackConstructor::JSCallbackConstructor(PassRefPtr<Structure> structure, JSClassRef jsClass, JSObjectCallAsConstructorCallback callback)
+JSCallbackConstructor::JSCallbackConstructor(NonNullPassRefPtr<Structure> structure, JSClassRef jsClass, JSObjectCallAsConstructorCallback callback)
     : JSObject(structure)
     , m_class(jsClass)
     , m_callback(callback)
@@ -66,7 +67,7 @@ static JSObject* constructJSCallback(ExecState* exec, JSObject* constructor, con
         JSValueRef exception = 0;
         JSObjectRef result;
         {
-            JSLock::DropAllLocks dropAllLocks(exec);
+            APICallbackShim callbackShim(exec);
             result = callback(ctx, constructorRef, argumentCount, arguments.data(), &exception);
         }
         if (exception)
diff --git a/src/3rdparty/javascriptcore/JavaScriptCore/API/JSCallbackConstructor.h b/src/3rdparty/javascriptcore/JavaScriptCore/API/JSCallbackConstructor.h
index 0497aa2..c4bd7ad 100644
--- a/src/3rdparty/javascriptcore/JavaScriptCore/API/JSCallbackConstructor.h
+++ b/src/3rdparty/javascriptcore/JavaScriptCore/API/JSCallbackConstructor.h
@@ -33,7 +33,7 @@ namespace JSC {
 
 class JSCallbackConstructor : public JSObject {
 public:
-    JSCallbackConstructor(PassRefPtr<Structure>, JSClassRef, JSObjectCallAsConstructorCallback);
+    JSCallbackConstructor(NonNullPassRefPtr<Structure>, JSClassRef, JSObjectCallAsConstructorCallback);
     virtual ~JSCallbackConstructor();
     JSClassRef classRef() const { return m_class; }
     JSObjectCallAsConstructorCallback callback() const { return m_callback; }
@@ -41,9 +41,12 @@ public:
     
     static PassRefPtr<Structure> createStructure(JSValue proto) 
     { 
-        return Structure::create(proto, TypeInfo(ObjectType, ImplementsHasInstance | HasStandardGetOwnPropertySlot | HasDefaultMark | HasDefaultGetPropertyNames)); 
+        return Structure::create(proto, TypeInfo(ObjectType, StructureFlags)); 
     }
 
+protected:
+    static const unsigned StructureFlags = ImplementsHasInstance | JSObject::StructureFlags;
+
 private:
     virtual ConstructType getConstructData(ConstructData&);
     virtual const ClassInfo* classInfo() const { return &info; }
diff --git a/src/3rdparty/javascriptcore/JavaScriptCore/API/JSCallbackFunction.cpp b/src/3rdparty/javascriptcore/JavaScriptCore/API/JSCallbackFunction.cpp
index b7dd768..0e434d9 100644
--- a/src/3rdparty/javascriptcore/JavaScriptCore/API/JSCallbackFunction.cpp
+++ b/src/3rdparty/javascriptcore/JavaScriptCore/API/JSCallbackFunction.cpp
@@ -27,6 +27,7 @@
 #include <wtf/Platform.h>
 #include "JSCallbackFunction.h"
 
+#include "APIShims.h"
 #include "APICast.h"
 #include "CodeBlock.h"
 #include "JSFunction.h"
@@ -61,7 +62,7 @@ JSValue JSCallbackFunction::call(ExecState* exec, JSObject* functionObject, JSVa
     JSValueRef exception = 0;
     JSValueRef result;
     {
-        JSLock::DropAllLocks dropAllLocks(exec);
+        APICallbackShim callbackShim(exec);
         result = static_cast<JSCallbackFunction*>(functionObject)->m_callback(execRef, functionRef, thisObjRef, argumentCount, arguments.data(), &exception);
     }
     if (exception)
diff --git a/src/3rdparty/javascriptcore/JavaScriptCore/API/JSCallbackFunction.h b/src/3rdparty/javascriptcore/JavaScriptCore/API/JSCallbackFunction.h
index 3a17fa2..0cf25c4 100644
--- a/src/3rdparty/javascriptcore/JavaScriptCore/API/JSCallbackFunction.h
+++ b/src/3rdparty/javascriptcore/JavaScriptCore/API/JSCallbackFunction.h
@@ -41,7 +41,7 @@ public:
     // refactor the code so this override isn't necessary
     static PassRefPtr<Structure> createStructure(JSValue proto) 
     { 
-        return Structure::create(proto, TypeInfo(ObjectType, HasStandardGetOwnPropertySlot | HasDefaultMark)); 
+        return Structure::create(proto, TypeInfo(ObjectType, StructureFlags)); 
     }
 
 private:
diff --git a/src/3rdparty/javascriptcore/JavaScriptCore/API/JSCallbackObject.h b/src/3rdparty/javascriptcore/JavaScriptCore/API/JSCallbackObject.h
index e767cb5..2e25991 100644
--- a/src/3rdparty/javascriptcore/JavaScriptCore/API/JSCallbackObject.h
+++ b/src/3rdparty/javascriptcore/JavaScriptCore/API/JSCallbackObject.h
@@ -36,7 +36,7 @@ namespace JSC {
 template <class Base>
 class JSCallbackObject : public Base {
 public:
-    JSCallbackObject(ExecState*, PassRefPtr<Structure>, JSClassRef, void* data);
+    JSCallbackObject(ExecState*, NonNullPassRefPtr<Structure>, JSClassRef, void* data);
     JSCallbackObject(JSClassRef);
     virtual ~JSCallbackObject();
 
@@ -50,23 +50,27 @@ public:
 
     static PassRefPtr<Structure> createStructure(JSValue proto) 
     { 
-        return Structure::create(proto, TypeInfo(ObjectType, ImplementsHasInstance | OverridesHasInstance)); 
+        return Structure::create(proto, TypeInfo(ObjectType, StructureFlags)); 
     }
 
+protected:
+    static const unsigned StructureFlags = OverridesGetOwnPropertySlot | ImplementsHasInstance | OverridesHasInstance | OverridesMarkChildren | OverridesGetPropertyNames | Base::StructureFlags;
+
 private:
     virtual UString className() const;
 
     virtual bool getOwnPropertySlot(ExecState*, const Identifier&, PropertySlot&);
     virtual bool getOwnPropertySlot(ExecState*, unsigned, PropertySlot&);
+    virtual bool getOwnPropertyDescriptor(ExecState*, const Identifier&, PropertyDescriptor&);
     
     virtual void put(ExecState*, const Identifier&, JSValue, PutPropertySlot&);
 
-    virtual bool deleteProperty(ExecState*, const Identifier&, bool checkDontDelete = true);
-    virtual bool deleteProperty(ExecState*, unsigned, bool checkDontDelete = true);
+    virtual bool deleteProperty(ExecState*, const Identifier&);
+    virtual bool deleteProperty(ExecState*, unsigned);
 
     virtual bool hasInstance(ExecState* exec, JSValue value, JSValue proto);
 
-    virtual void getOwnPropertyNames(ExecState*, PropertyNameArray&, bool includeNonEnumerable = false);
+    virtual void getOwnPropertyNames(ExecState*, PropertyNameArray&, EnumerationMode mode = ExcludeDontEnumProperties);
 
     virtual double toNumber(ExecState*) const;
     virtual UString toString(ExecState*) const;
diff --git a/src/3rdparty/javascriptcore/JavaScriptCore/API/JSCallbackObjectFunctions.h b/src/3rdparty/javascriptcore/JavaScriptCore/API/JSCallbackObjectFunctions.h
index c84c191..4b28a99 100644
--- a/src/3rdparty/javascriptcore/JavaScriptCore/API/JSCallbackObjectFunctions.h
+++ b/src/3rdparty/javascriptcore/JavaScriptCore/API/JSCallbackObjectFunctions.h
@@ -24,6 +24,7 @@
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
  */
 
+#include "APIShims.h"
 #include "APICast.h"
 #include "Error.h"
 #include "JSCallbackFunction.h"
@@ -47,7 +48,7 @@ inline JSCallbackObject<Base>* JSCallbackObject<Base>::asCallbackObject(JSValue
 }
 
 template <class Base>
-JSCallbackObject<Base>::JSCallbackObject(ExecState* exec, PassRefPtr<Structure> structure, JSClassRef jsClass, void* data)
+JSCallbackObject<Base>::JSCallbackObject(ExecState* exec, NonNullPassRefPtr<Structure> structure, JSClassRef jsClass, void* data)
     : Base(structure)
     , m_callbackObjectData(new JSCallbackObjectData(data, jsClass))
 {
@@ -79,7 +80,7 @@ void JSCallbackObject<Base>::init(ExecState* exec)
     
     // initialize from base to derived
     for (int i = static_cast<int>(initRoutines.size()) - 1; i >= 0; i--) {
-        JSLock::DropAllLocks dropAllLocks(exec);
+        APICallbackShim callbackShim(exec);
         JSObjectInitializeCallback initialize = initRoutines[i];
         initialize(toRef(exec), toRef(this));
     }
@@ -117,7 +118,7 @@ bool JSCallbackObject<Base>::getOwnPropertySlot(ExecState* exec, const Identifie
         if (JSObjectHasPropertyCallback hasProperty = jsClass->hasProperty) {
             if (!propertyNameRef)
                 propertyNameRef = OpaqueJSString::create(propertyName.ustring());
-            JSLock::DropAllLocks dropAllLocks(exec);
+            APICallbackShim callbackShim(exec);
             if (hasProperty(ctx, thisRef, propertyNameRef.get())) {
                 slot.setCustom(this, callbackGetter);
                 return true;
@@ -128,18 +129,18 @@ bool JSCallbackObject<Base>::getOwnPropertySlot(ExecState* exec, const Identifie
             JSValueRef exception = 0;
             JSValueRef value;
             {
-                JSLock::DropAllLocks dropAllLocks(exec);
+                APICallbackShim callbackShim(exec);
                 value = getProperty(ctx, thisRef, propertyNameRef.get(), &exception);
             }
-            exec->setException(toJS(exec, exception));
-            if (value) {
-                slot.setValue(toJS(exec, value));
-                return true;
-            }
             if (exception) {
+                exec->setException(toJS(exec, exception));
                 slot.setValue(jsUndefined());
                 return true;
             }
+            if (value) {
+                slot.setValue(toJS(exec, value));
+                return true;
+            }
         }
         
         if (OpaqueJSClassStaticValuesTable* staticValues = jsClass->staticValues(exec)) {
@@ -167,6 +168,25 @@ bool JSCallbackObject<Base>::getOwnPropertySlot(ExecState* exec, unsigned proper
 }
 
 template <class Base>
+bool JSCallbackObject<Base>::getOwnPropertyDescriptor(ExecState* exec, const Identifier& propertyName, PropertyDescriptor& descriptor)
+{
+    PropertySlot slot;
+    if (getOwnPropertySlot(exec, propertyName, slot)) {
+        // Ideally we should return an access descriptor, but returning a value descriptor is better than nothing.
+        JSValue value = slot.getValue(exec, propertyName);
+        if (!exec->hadException())
+            descriptor.setValue(value);
+        // We don't know whether the property is configurable, but assume it is.
+        descriptor.setConfigurable(true);
+        // We don't know whether the property is enumerable (we could call getOwnPropertyNames() to find out), but assume it isn't.
+        descriptor.setEnumerable(false);
+        return true;
+    }
+
+    return Base::getOwnPropertyDescriptor(exec, propertyName, descriptor);
+}
+
+template <class Base>
 void JSCallbackObject<Base>::put(ExecState* exec, const Identifier& propertyName, JSValue value, PutPropertySlot& slot)
 {
     JSContextRef ctx = toRef(exec);
@@ -181,10 +201,11 @@ void JSCallbackObject<Base>::put(ExecState* exec, const Identifier& propertyName
             JSValueRef exception = 0;
             bool result;
             {
-                JSLock::DropAllLocks dropAllLocks(exec);
+                APICallbackShim callbackShim(exec);
                 result = setProperty(ctx, thisRef, propertyNameRef.get(), valueRef, &exception);
             }
-            exec->setException(toJS(exec, exception));
+            if (exception)
+                exec->setException(toJS(exec, exception));
             if (result || exception)
                 return;
         }
@@ -199,10 +220,11 @@ void JSCallbackObject<Base>::put(ExecState* exec, const Identifier& propertyName
                     JSValueRef exception = 0;
                     bool result;
                     {
-                        JSLock::DropAllLocks dropAllLocks(exec);
+                        APICallbackShim callbackShim(exec);
                         result = setProperty(ctx, thisRef, propertyNameRef.get(), valueRef, &exception);
                     }
-                    exec->setException(toJS(exec, exception));
+                    if (exception)
+                        exec->setException(toJS(exec, exception));
                     if (result || exception)
                         return;
                 } else
@@ -224,7 +246,7 @@ void JSCallbackObject<Base>::put(ExecState* exec, const Identifier& propertyName
 }
 
 template <class Base>
-bool JSCallbackObject<Base>::deleteProperty(ExecState* exec, const Identifier& propertyName, bool checkDontDelete)
+bool JSCallbackObject<Base>::deleteProperty(ExecState* exec, const Identifier& propertyName)
 {
     JSContextRef ctx = toRef(exec);
     JSObjectRef thisRef = toRef(this);
@@ -237,10 +259,11 @@ bool JSCallbackObject<Base>::deleteProperty(ExecState* exec, const Identifier& p
             JSValueRef exception = 0;
             bool result;
             {
-                JSLock::DropAllLocks dropAllLocks(exec);
+                APICallbackShim callbackShim(exec);
                 result = deleteProperty(ctx, thisRef, propertyNameRef.get(), &exception);
             }
-            exec->setException(toJS(exec, exception));
+            if (exception)
+                exec->setException(toJS(exec, exception));
             if (result || exception)
                 return true;
         }
@@ -262,13 +285,13 @@ bool JSCallbackObject<Base>::deleteProperty(ExecState* exec, const Identifier& p
         }
     }
     
-    return Base::deleteProperty(exec, propertyName, checkDontDelete);
+    return Base::deleteProperty(exec, propertyName);
 }
 
 template <class Base>
-bool JSCallbackObject<Base>::deleteProperty(ExecState* exec, unsigned propertyName, bool checkDontDelete)
+bool JSCallbackObject<Base>::deleteProperty(ExecState* exec, unsigned propertyName)
 {
-    return deleteProperty(exec, Identifier::from(exec, propertyName), checkDontDelete);
+    return deleteProperty(exec, Identifier::from(exec, propertyName));
 }
 
 template <class Base>
@@ -298,10 +321,11 @@ JSObject* JSCallbackObject<Base>::construct(ExecState* exec, JSObject* construct
             JSValueRef exception = 0;
             JSObject* result;
             {
-                JSLock::DropAllLocks dropAllLocks(exec);
+                APICallbackShim callbackShim(exec);
                 result = toJS(callAsConstructor(execRef, constructorRef, argumentCount, arguments.data(), &exception));
             }
-            exec->setException(toJS(exec, exception));
+            if (exception)
+                exec->setException(toJS(exec, exception));
             return result;
         }
     }
@@ -322,10 +346,11 @@ bool JSCallbackObject<Base>::hasInstance(ExecState* exec, JSValue value, JSValue
             JSValueRef exception = 0;
             bool result;
             {
-                JSLock::DropAllLocks dropAllLocks(exec);
+                APICallbackShim callbackShim(exec);
                 result = hasInstance(execRef, thisRef, valueRef, &exception);
             }
-            exec->setException(toJS(exec, exception));
+            if (exception)
+                exec->setException(toJS(exec, exception));
             return result;
         }
     }
@@ -360,10 +385,11 @@ JSValue JSCallbackObject<Base>::call(ExecState* exec, JSObject* functionObject,
             JSValueRef exception = 0;
             JSValue result;
             {
-                JSLock::DropAllLocks dropAllLocks(exec);
+                APICallbackShim callbackShim(exec);
                 result = toJS(exec, callAsFunction(execRef, functionRef, thisObjRef, argumentCount, arguments.data(), &exception));
             }
-            exec->setException(toJS(exec, exception));
+            if (exception)
+                exec->setException(toJS(exec, exception));
             return result;
         }
     }
@@ -373,14 +399,14 @@ JSValue JSCallbackObject<Base>::call(ExecState* exec, JSObject* functionObject,
 }
 
 template <class Base>
-void JSCallbackObject<Base>::getOwnPropertyNames(ExecState* exec, PropertyNameArray& propertyNames, bool includeNonEnumerable)
+void JSCallbackObject<Base>::getOwnPropertyNames(ExecState* exec, PropertyNameArray& propertyNames, EnumerationMode mode)
 {
     JSContextRef execRef = toRef(exec);
     JSObjectRef thisRef = toRef(this);
     
     for (JSClassRef jsClass = classRef(); jsClass; jsClass = jsClass->parentClass) {
         if (JSObjectGetPropertyNamesCallback getPropertyNames = jsClass->getPropertyNames) {
-            JSLock::DropAllLocks dropAllLocks(exec);
+            APICallbackShim callbackShim(exec);
             getPropertyNames(execRef, thisRef, toRef(&propertyNames));
         }
         
@@ -390,7 +416,7 @@ void JSCallbackObject<Base>::getOwnPropertyNames(ExecState* exec, PropertyNameAr
             for (iterator it = staticValues->begin(); it != end; ++it) {
                 UString::Rep* name = it->first.get();
                 StaticValueEntry* entry = it->second;
-                if (entry->getProperty && !(entry->attributes & kJSPropertyAttributeDontEnum))
+                if (entry->getProperty && (!(entry->attributes & kJSPropertyAttributeDontEnum) || (mode == IncludeDontEnumProperties)))
                     propertyNames.add(Identifier(exec, name));
             }
         }
@@ -401,13 +427,13 @@ void JSCallbackObject<Base>::getOwnPropertyNames(ExecState* exec, PropertyNameAr
             for (iterator it = staticFunctions->begin(); it != end; ++it) {
                 UString::Rep* name = it->first.get();
                 StaticFunctionEntry* entry = it->second;
-                if (!(entry->attributes & kJSPropertyAttributeDontEnum))
+                if (!(entry->attributes & kJSPropertyAttributeDontEnum) || (mode == IncludeDontEnumProperties))
                     propertyNames.add(Identifier(exec, name));
             }
         }
     }
     
-    Base::getOwnPropertyNames(exec, propertyNames, includeNonEnumerable);
+    Base::getOwnPropertyNames(exec, propertyNames, mode);
 }
 
 template <class Base>
@@ -426,7 +452,7 @@ double JSCallbackObject<Base>::toNumber(ExecState* exec) const
             JSValueRef exception = 0;
             JSValueRef value;
             {
-                JSLock::DropAllLocks dropAllLocks(exec);
+                APICallbackShim callbackShim(exec);
                 value = convertToType(ctx, thisRef, kJSTypeNumber, &exception);
             }
             if (exception) {
@@ -435,7 +461,8 @@ double JSCallbackObject<Base>::toNumber(ExecState* exec) const
             }
 
             double dValue;
-            return toJS(exec, value).getNumber(dValue) ? dValue : NaN;
+            if (value)
+                return toJS(exec, value).getNumber(dValue) ? dValue : NaN;
         }
             
     return Base::toNumber(exec);
@@ -452,14 +479,15 @@ UString JSCallbackObject<Base>::toString(ExecState* exec) const
             JSValueRef exception = 0;
             JSValueRef value;
             {
-                JSLock::DropAllLocks dropAllLocks(exec);
+                APICallbackShim callbackShim(exec);
                 value = convertToType(ctx, thisRef, kJSTypeString, &exception);
             }
             if (exception) {
                 exec->setException(toJS(exec, exception));
                 return "";
             }
-            return toJS(exec, value).getString();
+            if (value)
+                return toJS(exec, value).getString(exec);
         }
             
     return Base::toString(exec);
@@ -504,16 +532,17 @@ JSValue JSCallbackObject<Base>::staticValueGetter(ExecState* exec, const Identif
                     JSValueRef exception = 0;
                     JSValueRef value;
                     {
-                        JSLock::DropAllLocks dropAllLocks(exec);
+                        APICallbackShim callbackShim(exec);
                         value = getProperty(toRef(exec), thisRef, propertyNameRef.get(), &exception);
                     }
-                    exec->setException(toJS(exec, exception));
+                    if (exception) {
+                        exec->setException(toJS(exec, exception));
+                        return jsUndefined();
+                    }
                     if (value)
                         return toJS(exec, value);
-                    if (exception)
-                        return jsUndefined();
                 }
-                    
+
     return throwError(exec, ReferenceError, "Static value property defined with NULL getProperty callback.");
 }
 
@@ -557,14 +586,15 @@ JSValue JSCallbackObject<Base>::callbackGetter(ExecState* exec, const Identifier
             JSValueRef exception = 0;
             JSValueRef value;
             {
-                JSLock::DropAllLocks dropAllLocks(exec);
+                APICallbackShim callbackShim(exec);
                 value = getProperty(toRef(exec), thisRef, propertyNameRef.get(), &exception);
             }
-            exec->setException(toJS(exec, exception));
+            if (exception) {
+                exec->setException(toJS(exec, exception));
+                return jsUndefined();
+            }
             if (value)
                 return toJS(exec, value);
-            if (exception)
-                return jsUndefined();
         }
             
     return throwError(exec, ReferenceError, "hasProperty callback returned true for a property that doesn't exist.");
diff --git a/src/3rdparty/javascriptcore/JavaScriptCore/API/JSClassRef.cpp b/src/3rdparty/javascriptcore/JavaScriptCore/API/JSClassRef.cpp
index afde7ce..c6685bf 100644
--- a/src/3rdparty/javascriptcore/JavaScriptCore/API/JSClassRef.cpp
+++ b/src/3rdparty/javascriptcore/JavaScriptCore/API/JSClassRef.cpp
@@ -34,6 +34,7 @@
 #include <runtime/ObjectPrototype.h>
 #include <runtime/Identifier.h>
 
+using namespace std;
 using namespace JSC;
 
 const JSClassDefinition kJSClassDefinitionEmpty = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
@@ -52,7 +53,7 @@ OpaqueJSClass::OpaqueJSClass(const JSClassDefinition* definition, OpaqueJSClass*
     , callAsConstructor(definition->callAsConstructor)
     , hasInstance(definition->hasInstance)
     , convertToType(definition->convertToType)
-    , m_className(UString::Rep::createFromUTF8(definition->className))
+    , m_className(UString::createFromUTF8(definition->className).rep()->ref())
     , m_staticValues(0)
     , m_staticFunctions(0)
 {
@@ -61,8 +62,9 @@ OpaqueJSClass::OpaqueJSClass(const JSClassDefinition* definition, OpaqueJSClass*
     if (const JSStaticValue* staticValue = definition->staticValues) {
         m_staticValues = new OpaqueJSClassStaticValuesTable();
         while (staticValue->name) {
-            m_staticValues->add(UString::Rep::createFromUTF8(staticValue->name),
-                              new StaticValueEntry(staticValue->getProperty, staticValue->setProperty, staticValue->attributes));
+            // Use a local variable here to sidestep an RVCT compiler bug.
+            StaticValueEntry* entry = new StaticValueEntry(staticValue->getProperty, staticValue->setProperty, staticValue->attributes);
+            m_staticValues->add(UString::createFromUTF8(staticValue->name).rep()->ref(), entry);
             ++staticValue;
         }
     }
@@ -70,8 +72,9 @@ OpaqueJSClass::OpaqueJSClass(const JSClassDefinition* definition, OpaqueJSClass*
     if (const JSStaticFunction* staticFunction = definition->staticFunctions) {
         m_staticFunctions = new OpaqueJSClassStaticFunctionsTable();
         while (staticFunction->name) {
-            m_staticFunctions->add(UString::Rep::createFromUTF8(staticFunction->name),
-                                 new StaticFunctionEntry(staticFunction->callAsFunction, staticFunction->attributes));
+            // Use a local variable here to sidestep an RVCT compiler bug.
+            StaticFunctionEntry* entry = new StaticFunctionEntry(staticFunction->callAsFunction, staticFunction->attributes);
+            m_staticFunctions->add(UString::createFromUTF8(staticFunction->name).rep()->ref(), entry);
             ++staticFunction;
         }
     }
@@ -82,12 +85,12 @@ OpaqueJSClass::OpaqueJSClass(const JSClassDefinition* definition, OpaqueJSClass*
 
 OpaqueJSClass::~OpaqueJSClass()
 {
-    ASSERT(!m_className.rep()->identifierTable());
+    ASSERT(!m_className.rep()->isIdentifier());
 
     if (m_staticValues) {
         OpaqueJSClassStaticValuesTable::const_iterator end = m_staticValues->end();
         for (OpaqueJSClassStaticValuesTable::const_iterator it = m_staticValues->begin(); it != end; ++it) {
-            ASSERT(!it->first->identifierTable());
+            ASSERT(!it->first->isIdentifier());
             delete it->second;
         }
         delete m_staticValues;
@@ -96,7 +99,7 @@ OpaqueJSClass::~OpaqueJSClass()
     if (m_staticFunctions) {
         OpaqueJSClassStaticFunctionsTable::const_iterator end = m_staticFunctions->end();
         for (OpaqueJSClassStaticFunctionsTable::const_iterator it = m_staticFunctions->begin(); it != end; ++it) {
-            ASSERT(!it->first->identifierTable());
+            ASSERT(!it->first->isIdentifier());
             delete it->second;
         }
         delete m_staticFunctions;
@@ -118,39 +121,32 @@ static void clearReferenceToPrototype(JSObjectRef prototype)
     jsClassData->cachedPrototype = 0;
 }
 
-PassRefPtr<OpaqueJSClass> OpaqueJSClass::create(const JSClassDefinition* definition)
+PassRefPtr<OpaqueJSClass> OpaqueJSClass::create(const JSClassDefinition* clientDefinition)
 {
-    if (const JSStaticFunction* staticFunctions = definition->staticFunctions) {
-        // copy functions into a prototype class
-        JSClassDefinition protoDefinition = kJSClassDefinitionEmpty;
-        protoDefinition.staticFunctions = staticFunctions;
-        protoDefinition.finalize = clearReferenceToPrototype;
-        
-        // We are supposed to use JSClassRetain/Release but since we know that we currently have
-        // the only reference to this class object we cheat and use a RefPtr instead.
-        RefPtr<OpaqueJSClass> protoClass = adoptRef(new OpaqueJSClass(&protoDefinition, 0));
-
-        // remove functions from the original class
-        JSClassDefinition objectDefinition = *definition;
-        objectDefinition.staticFunctions = 0;
-
-        return adoptRef(new OpaqueJSClass(&objectDefinition, protoClass.get()));
-    }
+    JSClassDefinition definition = *clientDefinition; // Avoid modifying client copy.
 
-    return adoptRef(new OpaqueJSClass(definition, 0));
+    JSClassDefinition protoDefinition = kJSClassDefinitionEmpty;
+    protoDefinition.finalize = clearReferenceToPrototype;
+    swap(definition.staticFunctions, protoDefinition.staticFunctions); // Move static functions to the prototype.
+    
+    // We are supposed to use JSClassRetain/Release but since we know that we currently have
+    // the only reference to this class object we cheat and use a RefPtr instead.
+    RefPtr<OpaqueJSClass> protoClass = adoptRef(new OpaqueJSClass(&protoDefinition, 0));
+    return adoptRef(new OpaqueJSClass(&definition, protoClass.get()));
 }
 
 OpaqueJSClassContextData::OpaqueJSClassContextData(OpaqueJSClass* jsClass)
     : m_class(jsClass)
-    , cachedPrototype(0)
 {
     if (jsClass->m_staticValues) {
         staticValues = new OpaqueJSClassStaticValuesTable;
         OpaqueJSClassStaticValuesTable::const_iterator end = jsClass->m_staticValues->end();
         for (OpaqueJSClassStaticValuesTable::const_iterator it = jsClass->m_staticValues->begin(); it != end; ++it) {
-            ASSERT(!it->first->identifierTable());
-            staticValues->add(UString::Rep::createCopying(it->first->data(), it->first->size()),
-                              new StaticValueEntry(it->second->getProperty, it->second->setProperty, it->second->attributes));
+            ASSERT(!it->first->isIdentifier());
+            // Use a local variable here to sidestep an RVCT compiler bug.
+            StaticValueEntry* entry = new StaticValueEntry(it->second->getProperty, it->second->setProperty, it->second->attributes);
+            staticValues->add(UString::Rep::create(it->first->data(), it->first->size()), entry);
+
         }
             
     } else
@@ -161,9 +157,10 @@ OpaqueJSClassContextData::OpaqueJSClassContextData(OpaqueJSClass* jsClass)
         staticFunctions = new OpaqueJSClassStaticFunctionsTable;
         OpaqueJSClassStaticFunctionsTable::const_iterator end = jsClass->m_staticFunctions->end();
         for (OpaqueJSClassStaticFunctionsTable::const_iterator it = jsClass->m_staticFunctions->begin(); it != end; ++it) {
-            ASSERT(!it->first->identifierTable());
-            staticFunctions->add(UString::Rep::createCopying(it->first->data(), it->first->size()),
-                              new StaticFunctionEntry(it->second->callAsFunction, it->second->attributes));
+            ASSERT(!it->first->isIdentifier());
+            // Use a local variable here to sidestep an RVCT compiler bug.
+            StaticFunctionEntry* entry = new StaticFunctionEntry(it->second->callAsFunction, it->second->attributes);
+            staticFunctions->add(UString::Rep::create(it->first->data(), it->first->size()), entry);
         }
             
     } else
@@ -240,5 +237,5 @@ JSObject* OpaqueJSClass::prototype(ExecState* exec)
                 jsClassData.cachedPrototype->setPrototype(prototype);
         }
     }
-    return jsClassData.cachedPrototype;
+    return jsClassData.cachedPrototype.get();
 }
diff --git a/src/3rdparty/javascriptcore/JavaScriptCore/API/JSClassRef.h b/src/3rdparty/javascriptcore/JavaScriptCore/API/JSClassRef.h
index c4777dd..ae60aad 100644
--- a/src/3rdparty/javascriptcore/JavaScriptCore/API/JSClassRef.h
+++ b/src/3rdparty/javascriptcore/JavaScriptCore/API/JSClassRef.h
@@ -31,6 +31,7 @@
 #include <runtime/JSObject.h>
 #include <runtime/Protect.h>
 #include <runtime/UString.h>
+#include <runtime/WeakGCPtr.h>
 #include <wtf/HashMap.h>
 #include <wtf/RefCounted.h>
 
@@ -76,7 +77,7 @@ struct OpaqueJSClassContextData : Noncopyable {
 
     OpaqueJSClassStaticValuesTable* staticValues;
     OpaqueJSClassStaticFunctionsTable* staticFunctions;
-    JSC::JSObject* cachedPrototype;
+    JSC::WeakGCPtr<JSC::JSObject> cachedPrototype;
 };
 
 struct OpaqueJSClass : public ThreadSafeShared<OpaqueJSClass> {
diff --git a/src/3rdparty/javascriptcore/JavaScriptCore/API/JSContextRef.cpp b/src/3rdparty/javascriptcore/JavaScriptCore/API/JSContextRef.cpp
index c358a84..6bdc3c8 100644
--- a/src/3rdparty/javascriptcore/JavaScriptCore/API/JSContextRef.cpp
+++ b/src/3rdparty/javascriptcore/JavaScriptCore/API/JSContextRef.cpp
@@ -25,6 +25,7 @@
 
 #include "config.h"
 #include "JSContextRef.h"
+#include "JSContextRefPrivate.h"
 
 #include "APICast.h"
 #include "InitializeThreading.h"
@@ -34,7 +35,7 @@
 #include "JSObject.h"
 #include <wtf/Platform.h>
 
-#if PLATFORM(DARWIN)
+#if OS(DARWIN)
 #include <mach-o/dyld.h>
 
 static const int32_t webkitFirstVersionWithConcurrentGlobalContexts = 0x2100500; // 528.5.0
@@ -45,7 +46,7 @@ using namespace JSC;
 JSContextGroupRef JSContextGroupCreate()
 {
     initializeThreading();
-    return toRef(JSGlobalData::create().releaseRef());
+    return toRef(JSGlobalData::createNonDefault().releaseRef());
 }
 
 JSContextGroupRef JSContextGroupRetain(JSContextGroupRef group)
@@ -62,7 +63,7 @@ void JSContextGroupRelease(JSContextGroupRef group)
 JSGlobalContextRef JSGlobalContextCreate(JSClassRef globalObjectClass)
 {
     initializeThreading();
-#if PLATFORM(DARWIN)
+#if OS(DARWIN)
     // When running on Tiger or Leopard, or if the application was linked before JSGlobalContextCreate was changed
     // to use a unique JSGlobalData, we use a shared one for compatibility.
 #if !defined(BUILDING_ON_TIGER) && !defined(BUILDING_ON_LEOPARD)
@@ -73,7 +74,7 @@ JSGlobalContextRef JSGlobalContextCreate(JSClassRef globalObjectClass)
         JSLock lock(LockForReal);
         return JSGlobalContextCreateInGroup(toRef(&JSGlobalData::sharedInstance()), globalObjectClass);
     }
-#endif // PLATFORM(DARWIN)
+#endif // OS(DARWIN)
 
     return JSGlobalContextCreateInGroup(0, globalObjectClass);
 }
@@ -83,8 +84,9 @@ JSGlobalContextRef JSGlobalContextCreateInGroup(JSContextGroupRef group, JSClass
     initializeThreading();
 
     JSLock lock(LockForReal);
+    RefPtr<JSGlobalData> globalData = group ? PassRefPtr<JSGlobalData>(toJS(group)) : JSGlobalData::createNonDefault();
 
-    RefPtr<JSGlobalData> globalData = group ? PassRefPtr<JSGlobalData>(toJS(group)) : JSGlobalData::create();
+    APIEntryShim entryShim(globalData.get(), false);
 
 #if ENABLE(JSC_MULTIPLE_THREADS)
     globalData->makeUsableFromMultipleThreads();
@@ -107,12 +109,9 @@ JSGlobalContextRef JSGlobalContextCreateInGroup(JSContextGroupRef group, JSClass
 JSGlobalContextRef JSGlobalContextRetain(JSGlobalContextRef ctx)
 {
     ExecState* exec = toJS(ctx);
-    JSLock lock(exec);
+    APIEntryShim entryShim(exec);
 
     JSGlobalData& globalData = exec->globalData();
-
-    globalData.heap.registerThread();
-
     gcProtect(exec->dynamicGlobalObject());
     globalData.ref();
     return ctx;
@@ -121,18 +120,16 @@ JSGlobalContextRef JSGlobalContextRetain(JSGlobalContextRef ctx)
 void JSGlobalContextRelease(JSGlobalContextRef ctx)
 {
     ExecState* exec = toJS(ctx);
-    JSLock lock(exec);
+    APIEntryShim entryShim(exec, false);
 
     gcUnprotect(exec->dynamicGlobalObject());
 
     JSGlobalData& globalData = exec->globalData();
     if (globalData.refCount() == 2) { // One reference is held by JSGlobalObject, another added by JSGlobalContextRetain().
         // The last reference was released, this is our last chance to collect.
-        ASSERT(!globalData.heap.protectedObjectCount());
-        ASSERT(!globalData.heap.isBusy());
         globalData.heap.destroy();
     } else
-        globalData.heap.collect();
+        globalData.heap.collectAllGarbage();
 
     globalData.deref();
 }
@@ -140,8 +137,7 @@ void JSGlobalContextRelease(JSGlobalContextRef ctx)
 JSObjectRef JSContextGetGlobalObject(JSContextRef ctx)
 {
     ExecState* exec = toJS(ctx);
-    exec->globalData().heap.registerThread();
-    JSLock lock(exec);
+    APIEntryShim entryShim(exec);
 
     // It is necessary to call toThisObject to get the wrapper object when used with WebCore.
     return toRef(exec->lexicalGlobalObject()->toThisObject(exec));
@@ -152,3 +148,11 @@ JSContextGroupRef JSContextGetGroup(JSContextRef ctx)
     ExecState* exec = toJS(ctx);
     return toRef(&exec->globalData());
 }
+
+JSGlobalContextRef JSContextGetGlobalContext(JSContextRef ctx)
+{
+    ExecState* exec = toJS(ctx);
+    APIEntryShim entryShim(exec);
+
+    return toGlobalRef(exec->lexicalGlobalObject()->globalExec());
+}
diff --git a/src/3rdparty/javascriptcore/JavaScriptCore/API/JSContextRefPrivate.h b/src/3rdparty/javascriptcore/JavaScriptCore/API/JSContextRefPrivate.h
new file mode 100644
index 0000000..ff014ec
--- /dev/null
+++ b/src/3rdparty/javascriptcore/JavaScriptCore/API/JSContextRefPrivate.h
@@ -0,0 +1,53 @@
+/*
+ * Copyright (C) 2009 Apple Computer, Inc.  All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
+ * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
+ * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+ * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+ * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
+ * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 
+ */
+
+#ifndef JSContextRefPrivate_h
+#define JSContextRefPrivate_h
+
+#include <JavaScriptCore/JSObjectRef.h>
+#include <JavaScriptCore/JSValueRef.h>
+#include <JavaScriptCore/WebKitAvailability.h>
+
+#ifndef __cplusplus
+#include <stdbool.h>
+#endif
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/*!
+@function
+@abstract Gets the global context of a JavaScript execution context.
+@param ctx The JSContext whose global context you want to get.
+@result ctx's global context.
+*/
+JS_EXPORT JSGlobalContextRef JSContextGetGlobalContext(JSContextRef ctx);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* JSContextRefPrivate_h */
diff --git a/src/3rdparty/javascriptcore/JavaScriptCore/API/JSObjectRef.cpp b/src/3rdparty/javascriptcore/JavaScriptCore/API/JSObjectRef.cpp
index 06ef578..faaa4eb 100644
--- a/src/3rdparty/javascriptcore/JavaScriptCore/API/JSObjectRef.cpp
+++ b/src/3rdparty/javascriptcore/JavaScriptCore/API/JSObjectRef.cpp
@@ -76,8 +76,7 @@ void JSClassRelease(JSClassRef jsClass)
 JSObjectRef JSObjectMake(JSContextRef ctx, JSClassRef jsClass, void* data)
 {
     ExecState* exec = toJS(ctx);
-    exec->globalData().heap.registerThread();
-    JSLock lock(exec);
+    APIEntryShim entryShim(exec);
 
     if (!jsClass)
         return toRef(new (exec) JSObject(exec->lexicalGlobalObject()->emptyObjectStructure())); // slightly more efficient
@@ -92,8 +91,7 @@ JSObjectRef JSObjectMake(JSContextRef ctx, JSClassRef jsClass, void* data)
 JSObjectRef JSObjectMakeFunctionWithCallback(JSContextRef ctx, JSStringRef name, JSObjectCallAsFunctionCallback callAsFunction)
 {
     ExecState* exec = toJS(ctx);
-    exec->globalData().heap.registerThread();
-    JSLock lock(exec);
+    APIEntryShim entryShim(exec);
 
     Identifier nameID = name ? name->identifier(&exec->globalData()) : Identifier(exec, "anonymous");
     
@@ -103,8 +101,7 @@ JSObjectRef JSObjectMakeFunctionWithCallback(JSContextRef ctx, JSStringRef name,
 JSObjectRef JSObjectMakeConstructor(JSContextRef ctx, JSClassRef jsClass, JSObjectCallAsConstructorCallback callAsConstructor)
 {
     ExecState* exec = toJS(ctx);
-    exec->globalData().heap.registerThread();
-    JSLock lock(exec);
+    APIEntryShim entryShim(exec);
 
     JSValue jsPrototype = jsClass ? jsClass->prototype(exec) : 0;
     if (!jsPrototype)
@@ -118,8 +115,7 @@ JSObjectRef JSObjectMakeConstructor(JSContextRef ctx, JSClassRef jsClass, JSObje
 JSObjectRef JSObjectMakeFunction(JSContextRef ctx, JSStringRef name, unsigned parameterCount, const JSStringRef parameterNames[], JSStringRef body, JSStringRef sourceURL, int startingLineNumber, JSValueRef* exception)
 {
     ExecState* exec = toJS(ctx);
-    exec->globalData().heap.registerThread();
-    JSLock lock(exec);
+    APIEntryShim entryShim(exec);
 
     Identifier nameID = name ? name->identifier(&exec->globalData()) : Identifier(exec, "anonymous");
     
@@ -141,8 +137,7 @@ JSObjectRef JSObjectMakeFunction(JSContextRef ctx, JSStringRef name, unsigned pa
 JSObjectRef JSObjectMakeArray(JSContextRef ctx, size_t argumentCount, const JSValueRef arguments[],  JSValueRef* exception)
 {
     ExecState* exec = toJS(ctx);
-    exec->globalData().heap.registerThread();
-    JSLock lock(exec);
+    APIEntryShim entryShim(exec);
 
     JSObject* result;
     if (argumentCount) {
@@ -167,8 +162,7 @@ JSObjectRef JSObjectMakeArray(JSContextRef ctx, size_t argumentCount, const JSVa
 JSObjectRef JSObjectMakeDate(JSContextRef ctx, size_t argumentCount, const JSValueRef arguments[],  JSValueRef* exception)
 {
     ExecState* exec = toJS(ctx);
-    exec->globalData().heap.registerThread();
-    JSLock lock(exec);
+    APIEntryShim entryShim(exec);
 
     MarkedArgumentBuffer argList;
     for (size_t i = 0; i < argumentCount; ++i)
@@ -188,8 +182,7 @@ JSObjectRef JSObjectMakeDate(JSContextRef ctx, size_t argumentCount, const JSVal
 JSObjectRef JSObjectMakeError(JSContextRef ctx, size_t argumentCount, const JSValueRef arguments[],  JSValueRef* exception)
 {
     ExecState* exec = toJS(ctx);
-    exec->globalData().heap.registerThread();
-    JSLock lock(exec);
+    APIEntryShim entryShim(exec);
 
     MarkedArgumentBuffer argList;
     for (size_t i = 0; i < argumentCount; ++i)
@@ -209,8 +202,7 @@ JSObjectRef JSObjectMakeError(JSContextRef ctx, size_t argumentCount, const JSVa
 JSObjectRef JSObjectMakeRegExp(JSContextRef ctx, size_t argumentCount, const JSValueRef arguments[],  JSValueRef* exception)
 {
     ExecState* exec = toJS(ctx);
-    exec->globalData().heap.registerThread();
-    JSLock lock(exec);
+    APIEntryShim entryShim(exec);
 
     MarkedArgumentBuffer argList;
     for (size_t i = 0; i < argumentCount; ++i)
@@ -230,8 +222,7 @@ JSObjectRef JSObjectMakeRegExp(JSContextRef ctx, size_t argumentCount, const JSV
 JSValueRef JSObjectGetPrototype(JSContextRef ctx, JSObjectRef object)
 {
     ExecState* exec = toJS(ctx);
-    exec->globalData().heap.registerThread();
-    JSLock lock(exec);
+    APIEntryShim entryShim(exec);
 
     JSObject* jsObject = toJS(object);
     return toRef(exec, jsObject->prototype());
@@ -240,8 +231,7 @@ JSValueRef JSObjectGetPrototype(JSContextRef ctx, JSObjectRef object)
 void JSObjectSetPrototype(JSContextRef ctx, JSObjectRef object, JSValueRef value)
 {
     ExecState* exec = toJS(ctx);
-    exec->globalData().heap.registerThread();
-    JSLock lock(exec);
+    APIEntryShim entryShim(exec);
 
     JSObject* jsObject = toJS(object);
     JSValue jsValue = toJS(exec, value);
@@ -252,8 +242,7 @@ void JSObjectSetPrototype(JSContextRef ctx, JSObjectRef object, JSValueRef value
 bool JSObjectHasProperty(JSContextRef ctx, JSObjectRef object, JSStringRef propertyName)
 {
     ExecState* exec = toJS(ctx);
-    exec->globalData().heap.registerThread();
-    JSLock lock(exec);
+    APIEntryShim entryShim(exec);
 
     JSObject* jsObject = toJS(object);
     
@@ -263,8 +252,7 @@ bool JSObjectHasProperty(JSContextRef ctx, JSObjectRef object, JSStringRef prope
 JSValueRef JSObjectGetProperty(JSContextRef ctx, JSObjectRef object, JSStringRef propertyName, JSValueRef* exception)
 {
     ExecState* exec = toJS(ctx);
-    exec->globalData().heap.registerThread();
-    JSLock lock(exec);
+    APIEntryShim entryShim(exec);
 
     JSObject* jsObject = toJS(object);
 
@@ -280,8 +268,7 @@ JSValueRef JSObjectGetProperty(JSContextRef ctx, JSObjectRef object, JSStringRef
 void JSObjectSetProperty(JSContextRef ctx, JSObjectRef object, JSStringRef propertyName, JSValueRef value, JSPropertyAttributes attributes, JSValueRef* exception)
 {
     ExecState* exec = toJS(ctx);
-    exec->globalData().heap.registerThread();
-    JSLock lock(exec);
+    APIEntryShim entryShim(exec);
 
     JSObject* jsObject = toJS(object);
     Identifier name(propertyName->identifier(&exec->globalData()));
@@ -304,8 +291,7 @@ void JSObjectSetProperty(JSContextRef ctx, JSObjectRef object, JSStringRef prope
 JSValueRef JSObjectGetPropertyAtIndex(JSContextRef ctx, JSObjectRef object, unsigned propertyIndex, JSValueRef* exception)
 {
     ExecState* exec = toJS(ctx);
-    exec->globalData().heap.registerThread();
-    JSLock lock(exec);
+    APIEntryShim entryShim(exec);
 
     JSObject* jsObject = toJS(object);
 
@@ -322,8 +308,7 @@ JSValueRef JSObjectGetPropertyAtIndex(JSContextRef ctx, JSObjectRef object, unsi
 void JSObjectSetPropertyAtIndex(JSContextRef ctx, JSObjectRef object, unsigned propertyIndex, JSValueRef value, JSValueRef* exception)
 {
     ExecState* exec = toJS(ctx);
-    exec->globalData().heap.registerThread();
-    JSLock lock(exec);
+    APIEntryShim entryShim(exec);
 
     JSObject* jsObject = toJS(object);
     JSValue jsValue = toJS(exec, value);
@@ -339,8 +324,7 @@ void JSObjectSetPropertyAtIndex(JSContextRef ctx, JSObjectRef object, unsigned p
 bool JSObjectDeleteProperty(JSContextRef ctx, JSObjectRef object, JSStringRef propertyName, JSValueRef* exception)
 {
     ExecState* exec = toJS(ctx);
-    exec->globalData().heap.registerThread();
-    JSLock lock(exec);
+    APIEntryShim entryShim(exec);
 
     JSObject* jsObject = toJS(object);
 
@@ -389,8 +373,7 @@ bool JSObjectIsFunction(JSContextRef, JSObjectRef object)
 JSValueRef JSObjectCallAsFunction(JSContextRef ctx, JSObjectRef object, JSObjectRef thisObject, size_t argumentCount, const JSValueRef arguments[], JSValueRef* exception)
 {
     ExecState* exec = toJS(ctx);
-    exec->globalData().heap.registerThread();
-    JSLock lock(exec);
+    APIEntryShim entryShim(exec);
 
     JSObject* jsObject = toJS(object);
     JSObject* jsThisObject = toJS(thisObject);
@@ -427,8 +410,7 @@ bool JSObjectIsConstructor(JSContextRef, JSObjectRef object)
 JSObjectRef JSObjectCallAsConstructor(JSContextRef ctx, JSObjectRef object, size_t argumentCount, const JSValueRef arguments[], JSValueRef* exception)
 {
     ExecState* exec = toJS(ctx);
-    exec->globalData().heap.registerThread();
-    JSLock lock(exec);
+    APIEntryShim entryShim(exec);
 
     JSObject* jsObject = toJS(object);
 
@@ -466,8 +448,7 @@ JSPropertyNameArrayRef JSObjectCopyPropertyNames(JSContextRef ctx, JSObjectRef o
 {
     JSObject* jsObject = toJS(object);
     ExecState* exec = toJS(ctx);
-    exec->globalData().heap.registerThread();
-    JSLock lock(exec);
+    APIEntryShim entryShim(exec);
 
     JSGlobalData* globalData = &exec->globalData();
 
@@ -492,7 +473,7 @@ JSPropertyNameArrayRef JSPropertyNameArrayRetain(JSPropertyNameArrayRef array)
 void JSPropertyNameArrayRelease(JSPropertyNameArrayRef array)
 {
     if (--array->refCount == 0) {
-        JSLock lock(array->globalData->isSharedInstance ? LockForReal : SilenceAssertionsOnly);
+        APIEntryShim entryShim(array->globalData, false);
         delete array;
     }
 }
@@ -510,9 +491,6 @@ JSStringRef JSPropertyNameArrayGetNameAtIndex(JSPropertyNameArrayRef array, size
 void JSPropertyNameAccumulatorAddName(JSPropertyNameAccumulatorRef array, JSStringRef propertyName)
 {
     PropertyNameArray* propertyNames = toJS(array);
-
-    propertyNames->globalData()->heap.registerThread();
-    JSLock lock(propertyNames->globalData()->isSharedInstance ? LockForReal : SilenceAssertionsOnly);
-
+    APIEntryShim entryShim(propertyNames->globalData());
     propertyNames->add(propertyName->identifier(propertyNames->globalData()));
 }
diff --git a/src/3rdparty/javascriptcore/JavaScriptCore/API/JSStringRef.h b/src/3rdparty/javascriptcore/JavaScriptCore/API/JSStringRef.h
index 41d8978..c58b958 100644
--- a/src/3rdparty/javascriptcore/JavaScriptCore/API/JSStringRef.h
+++ b/src/3rdparty/javascriptcore/JavaScriptCore/API/JSStringRef.h
@@ -37,7 +37,7 @@
 extern "C" {
 #endif
 
-#if (!defined(WIN32) && !defined(_WIN32) && !defined(__WINSCW__))
+#if !defined(WIN32) && !defined(_WIN32) && !defined(__WINSCW__)
 /*!
 @typedef JSChar
 @abstract A Unicode character.
diff --git a/src/3rdparty/javascriptcore/JavaScriptCore/API/JSValueRef.cpp b/src/3rdparty/javascriptcore/JavaScriptCore/API/JSValueRef.cpp
index 2207181..a12cc34 100644
--- a/src/3rdparty/javascriptcore/JavaScriptCore/API/JSValueRef.cpp
+++ b/src/3rdparty/javascriptcore/JavaScriptCore/API/JSValueRef.cpp
@@ -28,6 +28,7 @@
 
 #include <wtf/Platform.h>
 #include "APICast.h"
+#include "APIShims.h"
 #include "JSCallbackObject.h"
 
 #include <runtime/JSGlobalObject.h>
@@ -41,13 +42,14 @@
 
 #include <algorithm> // for std::min
 
-JSType JSValueGetType(JSContextRef ctx, JSValueRef value)
+using namespace JSC;
+
+::JSType JSValueGetType(JSContextRef ctx, JSValueRef value)
 {
-    JSC::ExecState* exec = toJS(ctx);
-    exec->globalData().heap.registerThread();
-    JSC::JSLock lock(exec);
+    ExecState* exec = toJS(ctx);
+    APIEntryShim entryShim(exec);
 
-    JSC::JSValue jsValue = toJS(exec, value);
+    JSValue jsValue = toJS(exec, value);
 
     if (jsValue.isUndefined())
         return kJSTypeUndefined;
@@ -63,13 +65,10 @@ JSType JSValueGetType(JSContextRef ctx, JSValueRef value)
     return kJSTypeObject;
 }
 
-using namespace JSC; // placed here to avoid conflict between JSC::JSType and JSType, above.
-
 bool JSValueIsUndefined(JSContextRef ctx, JSValueRef value)
 {
     ExecState* exec = toJS(ctx);
-    exec->globalData().heap.registerThread();
-    JSLock lock(exec);
+    APIEntryShim entryShim(exec);
 
     JSValue jsValue = toJS(exec, value);
     return jsValue.isUndefined();
@@ -78,8 +77,7 @@ bool JSValueIsUndefined(JSContextRef ctx, JSValueRef value)
 bool JSValueIsNull(JSContextRef ctx, JSValueRef value)
 {
     ExecState* exec = toJS(ctx);
-    exec->globalData().heap.registerThread();
-    JSLock lock(exec);
+    APIEntryShim entryShim(exec);
 
     JSValue jsValue = toJS(exec, value);
     return jsValue.isNull();
@@ -88,8 +86,7 @@ bool JSValueIsNull(JSContextRef ctx, JSValueRef value)
 bool JSValueIsBoolean(JSContextRef ctx, JSValueRef value)
 {
     ExecState* exec = toJS(ctx);
-    exec->globalData().heap.registerThread();
-    JSLock lock(exec);
+    APIEntryShim entryShim(exec);
 
     JSValue jsValue = toJS(exec, value);
     return jsValue.isBoolean();
@@ -98,8 +95,7 @@ bool JSValueIsBoolean(JSContextRef ctx, JSValueRef value)
 bool JSValueIsNumber(JSContextRef ctx, JSValueRef value)
 {
     ExecState* exec = toJS(ctx);
-    exec->globalData().heap.registerThread();
-    JSLock lock(exec);
+    APIEntryShim entryShim(exec);
 
     JSValue jsValue = toJS(exec, value);
     return jsValue.isNumber();
@@ -108,8 +104,7 @@ bool JSValueIsNumber(JSContextRef ctx, JSValueRef value)
 bool JSValueIsString(JSContextRef ctx, JSValueRef value)
 {
     ExecState* exec = toJS(ctx);
-    exec->globalData().heap.registerThread();
-    JSLock lock(exec);
+    APIEntryShim entryShim(exec);
 
     JSValue jsValue = toJS(exec, value);
     return jsValue.isString();
@@ -118,8 +113,7 @@ bool JSValueIsString(JSContextRef ctx, JSValueRef value)
 bool JSValueIsObject(JSContextRef ctx, JSValueRef value)
 {
     ExecState* exec = toJS(ctx);
-    exec->globalData().heap.registerThread();
-    JSLock lock(exec);
+    APIEntryShim entryShim(exec);
 
     JSValue jsValue = toJS(exec, value);
     return jsValue.isObject();
@@ -128,8 +122,7 @@ bool JSValueIsObject(JSContextRef ctx, JSValueRef value)
 bool JSValueIsObjectOfClass(JSContextRef ctx, JSValueRef value, JSClassRef jsClass)
 {
     ExecState* exec = toJS(ctx);
-    exec->globalData().heap.registerThread();
-    JSLock lock(exec);
+    APIEntryShim entryShim(exec);
 
     JSValue jsValue = toJS(exec, value);
     
@@ -145,8 +138,7 @@ bool JSValueIsObjectOfClass(JSContextRef ctx, JSValueRef value, JSClassRef jsCla
 bool JSValueIsEqual(JSContextRef ctx, JSValueRef a, JSValueRef b, JSValueRef* exception)
 {
     ExecState* exec = toJS(ctx);
-    exec->globalData().heap.registerThread();
-    JSLock lock(exec);
+    APIEntryShim entryShim(exec);
 
     JSValue jsA = toJS(exec, a);
     JSValue jsB = toJS(exec, b);
@@ -163,20 +155,18 @@ bool JSValueIsEqual(JSContextRef ctx, JSValueRef a, JSValueRef b, JSValueRef* ex
 bool JSValueIsStrictEqual(JSContextRef ctx, JSValueRef a, JSValueRef b)
 {
     ExecState* exec = toJS(ctx);
-    exec->globalData().heap.registerThread();
-    JSLock lock(exec);
+    APIEntryShim entryShim(exec);
 
     JSValue jsA = toJS(exec, a);
     JSValue jsB = toJS(exec, b);
 
-    return JSValue::strictEqual(jsA, jsB);
+    return JSValue::strictEqual(exec, jsA, jsB);
 }
 
 bool JSValueIsInstanceOfConstructor(JSContextRef ctx, JSValueRef value, JSObjectRef constructor, JSValueRef* exception)
 {
     ExecState* exec = toJS(ctx);
-    exec->globalData().heap.registerThread();
-    JSLock lock(exec);
+    APIEntryShim entryShim(exec);
 
     JSValue jsValue = toJS(exec, value);
 
@@ -195,8 +185,7 @@ bool JSValueIsInstanceOfConstructor(JSContextRef ctx, JSValueRef value, JSObject
 JSValueRef JSValueMakeUndefined(JSContextRef ctx)
 {
     ExecState* exec = toJS(ctx);
-    exec->globalData().heap.registerThread();
-    JSLock lock(exec);
+    APIEntryShim entryShim(exec);
 
     return toRef(exec, jsUndefined());
 }
@@ -204,8 +193,7 @@ JSValueRef JSValueMakeUndefined(JSContextRef ctx)
 JSValueRef JSValueMakeNull(JSContextRef ctx)
 {
     ExecState* exec = toJS(ctx);
-    exec->globalData().heap.registerThread();
-    JSLock lock(exec);
+    APIEntryShim entryShim(exec);
 
     return toRef(exec, jsNull());
 }
@@ -213,8 +201,7 @@ JSValueRef JSValueMakeNull(JSContextRef ctx)
 JSValueRef JSValueMakeBoolean(JSContextRef ctx, bool value)
 {
     ExecState* exec = toJS(ctx);
-    exec->globalData().heap.registerThread();
-    JSLock lock(exec);
+    APIEntryShim entryShim(exec);
 
     return toRef(exec, jsBoolean(value));
 }
@@ -222,8 +209,7 @@ JSValueRef JSValueMakeBoolean(JSContextRef ctx, bool value)
 JSValueRef JSValueMakeNumber(JSContextRef ctx, double value)
 {
     ExecState* exec = toJS(ctx);
-    exec->globalData().heap.registerThread();
-    JSLock lock(exec);
+    APIEntryShim entryShim(exec);
 
     return toRef(exec, jsNumber(exec, value));
 }
@@ -231,8 +217,7 @@ JSValueRef JSValueMakeNumber(JSContextRef ctx, double value)
 JSValueRef JSValueMakeString(JSContextRef ctx, JSStringRef string)
 {
     ExecState* exec = toJS(ctx);
-    exec->globalData().heap.registerThread();
-    JSLock lock(exec);
+    APIEntryShim entryShim(exec);
 
     return toRef(exec, jsString(exec, string->ustring()));
 }
@@ -240,8 +225,7 @@ JSValueRef JSValueMakeString(JSContextRef ctx, JSStringRef string)
 bool JSValueToBoolean(JSContextRef ctx, JSValueRef value)
 {
     ExecState* exec = toJS(ctx);
-    exec->globalData().heap.registerThread();
-    JSLock lock(exec);
+    APIEntryShim entryShim(exec);
 
     JSValue jsValue = toJS(exec, value);
     return jsValue.toBoolean(exec);
@@ -250,8 +234,7 @@ bool JSValueToBoolean(JSContextRef ctx, JSValueRef value)
 double JSValueToNumber(JSContextRef ctx, JSValueRef value, JSValueRef* exception)
 {
     ExecState* exec = toJS(ctx);
-    exec->globalData().heap.registerThread();
-    JSLock lock(exec);
+    APIEntryShim entryShim(exec);
 
     JSValue jsValue = toJS(exec, value);
 
@@ -268,8 +251,7 @@ double JSValueToNumber(JSContextRef ctx, JSValueRef value, JSValueRef* exception
 JSStringRef JSValueToStringCopy(JSContextRef ctx, JSValueRef value, JSValueRef* exception)
 {
     ExecState* exec = toJS(ctx);
-    exec->globalData().heap.registerThread();
-    JSLock lock(exec);
+    APIEntryShim entryShim(exec);
 
     JSValue jsValue = toJS(exec, value);
     
@@ -286,8 +268,7 @@ JSStringRef JSValueToStringCopy(JSContextRef ctx, JSValueRef value, JSValueRef*
 JSObjectRef JSValueToObject(JSContextRef ctx, JSValueRef value, JSValueRef* exception)
 {
     ExecState* exec = toJS(ctx);
-    exec->globalData().heap.registerThread();
-    JSLock lock(exec);
+    APIEntryShim entryShim(exec);
 
     JSValue jsValue = toJS(exec, value);
     
@@ -304,19 +285,17 @@ JSObjectRef JSValueToObject(JSContextRef ctx, JSValueRef value, JSValueRef* exce
 void JSValueProtect(JSContextRef ctx, JSValueRef value)
 {
     ExecState* exec = toJS(ctx);
-    exec->globalData().heap.registerThread();
-    JSLock lock(exec);
+    APIEntryShim entryShim(exec);
 
-    JSValue jsValue = toJS(exec, value);
+    JSValue jsValue = toJSForGC(exec, value);
     gcProtect(jsValue);
 }
 
 void JSValueUnprotect(JSContextRef ctx, JSValueRef value)
 {
     ExecState* exec = toJS(ctx);
-    exec->globalData().heap.registerThread();
-    JSLock lock(exec);
+    APIEntryShim entryShim(exec);
 
-    JSValue jsValue = toJS(exec, value);
+    JSValue jsValue = toJSForGC(exec, value);
     gcUnprotect(jsValue);
 }
diff --git a/src/3rdparty/javascriptcore/JavaScriptCore/API/OpaqueJSString.cpp b/src/3rdparty/javascriptcore/JavaScriptCore/API/OpaqueJSString.cpp
index 7c7b1af..f740abe 100644
--- a/src/3rdparty/javascriptcore/JavaScriptCore/API/OpaqueJSString.cpp
+++ b/src/3rdparty/javascriptcore/JavaScriptCore/API/OpaqueJSString.cpp
@@ -42,7 +42,7 @@ PassRefPtr<OpaqueJSString> OpaqueJSString::create(const UString& ustring)
 UString OpaqueJSString::ustring() const
 {
     if (this && m_characters)
-        return UString(m_characters, m_length, true);
+        return UString(m_characters, m_length);
     return UString::null();
 }