Source/JavaScriptCore/runtime/JSDestructibleObject.h

/*
 * Copyright (C) 2012-2019 Apple Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
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 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``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 INC. OR ITS CONTRIBUTORS
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#pragma once

#include "JSObject.h"

namespace JSC {

struct ClassInfo;

class JSDestructibleObject : public JSNonFinalObject {
public:
    typedef JSNonFinalObject Base;

    static constexpr bool needsDestruction = true;
    
    template<typename CellType, SubspaceAccess>
    static CompleteSubspace* subspaceFor(VM& vm)
    {
        return &vm.destructibleObjectSpace;
    }

    const ClassInfo* classInfo() const { return m_classInfo; }
    
    static ptrdiff_t classInfoOffset() { return OBJECT_OFFSETOF(JSDestructibleObject, m_classInfo); }

protected:
    JSDestructibleObject(VM& vm, Structure* structure, Butterfly* butterfly = 0)
        : JSNonFinalObject(vm, structure, butterfly)
        , m_classInfo(structure->classInfo())
    {
        ASSERT(m_classInfo);
    }

private:
    const ClassInfo* m_classInfo;
};

} // namespace JSC