jsobject.h

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    if (JSValuePtr* location = getDirectLocation(propertyName)) {
        if (m_structure->hasGetterSetterProperties() && location[0].isGetterSetter())
            fillGetterPropertySlot(slot, location);
        else
            slot.setValueSlot(this, location, offsetForLocation(location));
        return true;
    }

    // non-standard Netscape extension
    if (propertyName == exec->propertyNames().underscoreProto) {
        slot.setValue(prototype());
        return true;
    }

    return false;
}

ALWAYS_INLINE bool JSObject::getOwnPropertySlotForWrite(ExecState* exec, const Identifier& propertyName, PropertySlot& slot, bool& slotIsWriteable)
{
    unsigned attributes;
    if (JSValuePtr* location = getDirectLocation(propertyName, attributes)) {
        if (m_structure->hasGetterSetterProperties() && location[0].isGetterSetter()) {
            slotIsWriteable = false;
            fillGetterPropertySlot(slot, location);
        } else {
            slotIsWriteable = !(attributes & ReadOnly);
            slot.setValueSlot(this, location, offsetForLocation(location));
        }
        return true;
    }

    // non-standard Netscape extension
    if (propertyName == exec->propertyNames().underscoreProto) {
        slot.setValue(prototype());
        slotIsWriteable = false;
        return true;
    }

    return false;
}

// It may seem crazy to inline a function this large, especially a virtual function,
// but it makes a big difference to property lookup that derived classes can inline their
// base class call to this.
ALWAYS_INLINE bool JSObject::getOwnPropertySlot(ExecState* exec, const Identifier& propertyName, PropertySlot& slot)
{
    return inlineGetOwnPropertySlot(exec, propertyName, slot);
}

ALWAYS_INLINE bool JSCell::fastGetOwnPropertySlot(ExecState* exec, const Identifier& propertyName, PropertySlot& slot)
{
    if (structure()->typeInfo().hasStandardGetOwnPropertySlot())
        return asObject(this)->inlineGetOwnPropertySlot(exec, propertyName, slot);
    return getOwnPropertySlot(exec, propertyName, slot);
}

// It may seem crazy to inline a function this large but it makes a big difference
// since this is function very hot in variable lookup
inline bool JSObject::getPropertySlot(ExecState* exec, const Identifier& propertyName, PropertySlot& slot)
{
    JSObject* object = this;
    while (true) {
        if (object->fastGetOwnPropertySlot(exec, propertyName, slot))
            return true;
        JSValuePtr prototype = object->prototype();
        if (!prototype.isObject())
            return false;
        object = asObject(prototype);
    }
}

inline bool JSObject::getPropertySlot(ExecState* exec, unsigned propertyName, PropertySlot& slot)
{
    JSObject* object = this;
    while (true) {
        if (object->getOwnPropertySlot(exec, propertyName, slot))
            return true;
        JSValuePtr prototype = object->prototype();
        if (!prototype.isObject())
            return false;
        object = asObject(prototype);
    }
}

inline JSValuePtr JSObject::get(ExecState* exec, const Identifier& propertyName) const
{
    PropertySlot slot(this);
    if (const_cast<JSObject*>(this)->getPropertySlot(exec, propertyName, slot))
        return slot.getValue(exec, propertyName);
    
    return jsUndefined();
}

inline JSValuePtr JSObject::get(ExecState* exec, unsigned propertyName) const
{
    PropertySlot slot(this);
    if (const_cast<JSObject*>(this)->getPropertySlot(exec, propertyName, slot))
        return slot.getValue(exec, propertyName);

    return jsUndefined();
}

inline void JSObject::putDirect(const Identifier& propertyName, JSValuePtr value, unsigned attr)
{
    PutPropertySlot slot;
    putDirect(propertyName, value, attr, false, slot);
}

inline void JSObject::putDirect(const Identifier& propertyName, JSValuePtr value, unsigned attributes, bool checkReadOnly, PutPropertySlot& slot)
{
    ASSERT(!Heap::heap(value) || Heap::heap(value) == Heap::heap(this));

    if (m_structure->isDictionary()) {
        unsigned currentAttributes;
        size_t offset = m_structure->get(propertyName, currentAttributes);
        if (offset != WTF::notFound) {
            if (checkReadOnly && currentAttributes & ReadOnly)
                return;
            m_propertyStorage[offset] = value;
            slot.setExistingProperty(this, offset);
            return;
        }

        size_t currentCapacity = m_structure->propertyStorageCapacity();
        offset = m_structure->addPropertyWithoutTransition(propertyName, attributes);
        if (currentCapacity != m_structure->propertyStorageCapacity())
            allocatePropertyStorage(currentCapacity, m_structure->propertyStorageCapacity());

        ASSERT(offset < m_structure->propertyStorageCapacity());
        m_propertyStorage[offset] = value;
        slot.setNewProperty(this, offset);
        return;
    }

    size_t offset;
    size_t currentCapacity = m_structure->propertyStorageCapacity();
    if (RefPtr<Structure> structure = Structure::addPropertyTransitionToExistingStructure(m_structure, propertyName, attributes, offset)) {
        if (currentCapacity != structure->propertyStorageCapacity())
            allocatePropertyStorage(currentCapacity, structure->propertyStorageCapacity());

        ASSERT(offset < structure->propertyStorageCapacity());
        m_propertyStorage[offset] = value;
        slot.setNewProperty(this, offset);
        slot.setWasTransition(true);
        setStructure(structure.release());
        return;
    }

    unsigned currentAttributes;
    offset = m_structure->get(propertyName, currentAttributes);
    if (offset != WTF::notFound) {
        if (checkReadOnly && currentAttributes & ReadOnly)
            return;
        m_propertyStorage[offset] = value;
        slot.setExistingProperty(this, offset);
        return;
    }

    RefPtr<Structure> structure = Structure::addPropertyTransition(m_structure, propertyName, attributes, offset);
    if (currentCapacity != structure->propertyStorageCapacity())
        allocatePropertyStorage(currentCapacity, structure->propertyStorageCapacity());

    ASSERT(offset < structure->propertyStorageCapacity());
    m_propertyStorage[offset] = value;
    slot.setNewProperty(this, offset);
    slot.setWasTransition(true);
    setStructure(structure.release());
}

inline void JSObject::putDirectWithoutTransition(const Identifier& propertyName, JSValuePtr value, unsigned attributes)
{
    size_t currentCapacity = m_structure->propertyStorageCapacity();
    size_t offset = m_structure->addPropertyWithoutTransition(propertyName, attributes);
    if (currentCapacity != m_structure->propertyStorageCapacity())
        allocatePropertyStorage(currentCapacity, m_structure->propertyStorageCapacity());
    m_propertyStorage[offset] = value;
}

inline void JSObject::transitionTo(Structure* newStructure)
{
    if (m_structure->propertyStorageCapacity() != newStructure->propertyStorageCapacity())
        allocatePropertyStorage(m_structure->propertyStorageCapacity(), newStructure->propertyStorageCapacity());
    setStructure(newStructure);
}

inline JSValuePtr JSObject::toPrimitive(ExecState* exec, PreferredPrimitiveType preferredType) const
{
    return defaultValue(exec, preferredType);
}

inline JSValuePtr JSValuePtr::get(ExecState* exec, const Identifier& propertyName) const
{
    PropertySlot slot(asValue());
    return get(exec, propertyName, slot);
}

inline JSValuePtr JSValuePtr::get(ExecState* exec, const Identifier& propertyName, PropertySlot& slot) const
{
    if (UNLIKELY(!isCell())) {
        JSObject* prototype = JSImmediate::prototype(asValue(), exec);
        if (!prototype->getPropertySlot(exec, propertyName, slot))
            return jsUndefined();
        return slot.getValue(exec, propertyName);
    }
    JSCell* cell = asCell();
    while (true) {
        if (cell->fastGetOwnPropertySlot(exec, propertyName, slot))
            return slot.getValue(exec, propertyName);
        ASSERT(cell->isObject());
        JSValuePtr prototype = static_cast<JSObject*>(cell)->prototype();
        if (!prototype.isObject())
            return jsUndefined();
        cell = asObject(prototype);
    }
}

inline JSValuePtr JSValuePtr::get(ExecState* exec, unsigned propertyName) const
{
    PropertySlot slot(asValue());
    return get(exec, propertyName, slot);
}

inline JSValuePtr JSValuePtr::get(ExecState* exec, unsigned propertyName, PropertySlot& slot) const
{
    if (UNLIKELY(!isCell())) {
        JSObject* prototype = JSImmediate::prototype(asValue(), exec);
        if (!prototype->getPropertySlot(exec, propertyName, slot))
            return jsUndefined();
        return slot.getValue(exec, propertyName);
    }
    JSCell* cell = const_cast<JSCell*>(asCell());
    while (true) {
        if (cell->getOwnPropertySlot(exec, propertyName, slot))
            return slot.getValue(exec, propertyName);
        ASSERT(cell->isObject());
        JSValuePtr prototype = static_cast<JSObject*>(cell)->prototype();
        if (!prototype.isObject())
            return jsUndefined();
        cell = prototype.asCell();
    }
}

inline void JSValuePtr::put(ExecState* exec, const Identifier& propertyName, JSValuePtr value, PutPropertySlot& slot)
{
    if (UNLIKELY(!isCell())) {
        JSImmediate::toObject(asValue(), exec)->put(exec, propertyName, value, slot);
        return;
    }
    asCell()->put(exec, propertyName, value, slot);
}

inline void JSValuePtr::put(ExecState* exec, unsigned propertyName, JSValuePtr value)
{
    if (UNLIKELY(!isCell())) {
        JSImmediate::toObject(asValue(), exec)->put(exec, propertyName, value);
        return;
    }
    asCell()->put(exec, propertyName, value);
}

ALWAYS_INLINE void JSObject::allocatePropertyStorageInline(size_t oldSize, size_t newSize)
{
    ASSERT(newSize > oldSize);

    JSValuePtr* oldPropertyStorage = m_propertyStorage;
    m_propertyStorage = new JSValuePtr[newSize];

    for (unsigned i = 0; i < oldSize; ++i)
        m_propertyStorage[i] = oldPropertyStorage[i];

    if (oldPropertyStorage != m_inlineStorage)
        delete [] oldPropertyStorage;
}

} // namespace JSC

#endif // JSObject_h