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diff --git a/src/script/bridge/qscriptstaticscopeobject.cpp b/src/script/bridge/qscriptstaticscopeobject.cpp
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+/****************************************************************************
+**
+** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the QtScript module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL-ONLY$
+** GNU Lesser General Public License Usage
+** This file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "config.h"
+#include "qscriptstaticscopeobject_p.h"
+
+namespace JSC
+{
+    ASSERT_CLASS_FITS_IN_CELL(QT_PREPEND_NAMESPACE(QScriptStaticScopeObject));
+}
+
+QT_BEGIN_NAMESPACE
+
+/*!
+  \class QScriptStaticScopeObject
+  \internal
+
+    Represents a static scope object.
+
+    This class allows the VM to determine at JS script compile time whether
+    the object has a given property or not. If the object has the property,
+    a fast, index-based read/write operation will be used. If the object
+    doesn't have the property, the compiler knows it can safely skip this
+    object when dynamically resolving the property. Either way, this can
+    greatly improve performance.
+
+  \sa QScriptContext::pushScope()
+*/
+
+const JSC::ClassInfo QScriptStaticScopeObject::info = { "QScriptStaticScopeObject", 0, 0, 0 };
+
+/*!
+    Creates a static scope object with a fixed set of undeletable properties.
+
+    It's not possible to add new properties to the object after construction.
+*/
+QScriptStaticScopeObject::QScriptStaticScopeObject(WTF::NonNullPassRefPtr<JSC::Structure> structure,
+                                                   int propertyCount, const PropertyInfo* props)
+    : JSC::JSVariableObject(structure, new Data(/*canGrow=*/false))
+{
+    int index = growRegisterArray(propertyCount);
+    for (int i = 0; i < propertyCount; ++i, --index) {
+        const PropertyInfo& prop = props[i];
+        JSC::SymbolTableEntry entry(index, prop.attributes);
+        symbolTable().add(prop.identifier.ustring().rep(), entry);
+        registerAt(index) = prop.value;
+    }
+}
+
+/*!
+    Creates an empty static scope object.
+
+    Properties can be added to the object after construction, either by
+    calling QScriptValue::setProperty(), or by pushing the object on the
+    scope chain; variable declarations ("var" statements) and function
+    declarations in JavaScript will create properties on the scope object.
+
+    Note that once the scope object has been used in a closure and the
+    resulting function has been compiled, it's no longer safe to add
+    properties to the scope object (because the VM will bypass this
+    object the next time the function is executed).
+*/
+QScriptStaticScopeObject::QScriptStaticScopeObject(WTF::NonNullPassRefPtr<JSC::Structure> structure)
+    : JSC::JSVariableObject(structure, new Data(/*canGrow=*/true))
+{
+}
+
+QScriptStaticScopeObject::~QScriptStaticScopeObject()
+{
+    delete d;
+}
+
+bool QScriptStaticScopeObject::getOwnPropertySlot(JSC::ExecState*, const JSC::Identifier& propertyName, JSC::PropertySlot& slot)
+{
+    return symbolTableGet(propertyName, slot);
+}
+
+bool QScriptStaticScopeObject::getOwnPropertyDescriptor(JSC::ExecState*, const JSC::Identifier& propertyName, JSC::PropertyDescriptor& descriptor)
+{
+    return symbolTableGet(propertyName, descriptor);
+}
+
+void QScriptStaticScopeObject::putWithAttributes(JSC::ExecState* exec, const JSC::Identifier &propertyName, JSC::JSValue value, unsigned attributes)
+{
+    if (symbolTablePutWithAttributes(propertyName, value, attributes))
+        return;
+    Q_ASSERT(d_ptr()->canGrow);
+    addSymbolTableProperty(propertyName, value, attributes);
+}
+
+void QScriptStaticScopeObject::put(JSC::ExecState* exec, const JSC::Identifier& propertyName, JSC::JSValue value, JSC::PutPropertySlot&)
+{
+    if (symbolTablePut(propertyName, value))
+        return;
+    Q_ASSERT(d_ptr()->canGrow);
+    addSymbolTableProperty(propertyName, value, /*attributes=*/0);
+}
+
+bool QScriptStaticScopeObject::deleteProperty(JSC::ExecState*, const JSC::Identifier&)
+{
+    return false;
+}
+
+void QScriptStaticScopeObject::markChildren(JSC::MarkStack& markStack)
+{
+    JSC::Register* registerArray = d_ptr()->registerArray.get();
+    if (!registerArray)
+        return;
+    markStack.appendValues(reinterpret_cast<JSC::JSValue*>(registerArray), d_ptr()->registerArraySize);
+}
+
+void QScriptStaticScopeObject::addSymbolTableProperty(const JSC::Identifier& name, JSC::JSValue value, unsigned attributes)
+{
+    int index = growRegisterArray(1);
+    JSC::SymbolTableEntry newEntry(index, attributes | JSC::DontDelete);
+    symbolTable().add(name.ustring().rep(), newEntry);
+    registerAt(index) = value;
+}
+
+/*!
+  Grows the register array by \a count elements, and returns the offset of
+  the newly added elements (note that the register file grows downwards,
+  starting at index -1).
+*/
+int QScriptStaticScopeObject::growRegisterArray(int count)
+{
+    size_t oldSize = d_ptr()->registerArraySize;
+    size_t newSize = oldSize + count;
+    JSC::Register* registerArray = new JSC::Register[newSize];
+    if (d_ptr()->registerArray)
+        memcpy(registerArray + count, d_ptr()->registerArray.get(), oldSize * sizeof(JSC::Register));
+    setRegisters(registerArray + newSize, registerArray);
+    d_ptr()->registerArraySize = newSize;
+    return -oldSize - 1;
+}
+
+QT_END_NAMESPACE