weex_core/Source/include/JavaScriptCore/dfg/DFGOSRExitJumpPlaceholder.h

/*
 * Copyright (C) 2012 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 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 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. 
 */

#pragma once

#if ENABLE(DFG_JIT)

#include "DFGCommon.h"
#include "MacroAssembler.h"

namespace JSC { namespace DFG {

class JITCompiler;
class SpeculativeJIT;

class OSRExitJumpPlaceholder {
public:
    OSRExitJumpPlaceholder()
        : m_index(std::numeric_limits<unsigned>::max())
    {
    }

private:
    friend class SpeculativeJIT;
    
    OSRExitJumpPlaceholder(unsigned index)
        : m_index(index)
    {
    }

public:
    bool operator!() const { return m_index == std::numeric_limits<unsigned>::max(); }
    
    void fill(JITCompiler&, const MacroAssembler::JumpList&);
    void fill(SpeculativeJIT*, const MacroAssembler::JumpList&);
    
private:
    unsigned m_index;
};

} } // namespace JSC::DFG

#endif // ENABLE(DFG_JIT)