JavaScriptCore/kjs/LabelScope.h

/*
 * Copyright (C) 2008 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.
 * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
 *     its contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE 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 OR ITS 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
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 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#ifndef LabelScope_h
#define LabelScope_h

#include <wtf/PassRefPtr.h>
#include "LabelID.h"

namespace JSC {

    class Identifier;

    class LabelScope {
    public:
        enum Type { Loop, Switch, NamedLabel };

        LabelScope(Type type, const Identifier* name, int scopeDepth, PassRefPtr<LabelID> breakTarget, PassRefPtr<LabelID> continueTarget)
            : m_refCount(0)
            , m_type(type)
            , m_name(name)
            , m_scopeDepth(scopeDepth)
            , m_breakTarget(breakTarget)
            , m_continueTarget(continueTarget)
        {
        }

        // It doesn't really make sense to copy a LabelScope, but we need this copy
        // constructor to support moving LabelScopes in a Vector.

        LabelScope(const LabelScope& other)
            : m_refCount(other.m_refCount)
            , m_type(other.m_type)
            , m_name(other.m_name)
            , m_scopeDepth(other.m_scopeDepth)
            , m_breakTarget(other.m_breakTarget)
            , m_continueTarget(other.m_continueTarget)
        {
        }

        void ref() { ++m_refCount; }
        void deref()
        {
            --m_refCount;
            ASSERT(m_refCount >= 0);
        }
        int refCount() const { return m_refCount; }

        LabelID* breakTarget() const { return m_breakTarget.get(); }
        LabelID* continueTarget() const { return m_continueTarget.get(); }

        Type type() const { return m_type; }
        const Identifier* name() const { return m_name; }
        int scopeDepth() const { return m_scopeDepth; }

    private:
        int m_refCount;
        Type m_type;
        const Identifier* m_name;
        int m_scopeDepth;
        RefPtr<LabelID> m_breakTarget;
        RefPtr<LabelID> m_continueTarget;
    };

} // namespace JSC

#endif // LabelScope_h