Source/JavaScriptCore/b3/B3PureCSE.h

/*
 * Copyright (C) 2016 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
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 */

#pragma once

#if ENABLE(B3_JIT)

#include "B3ValueKey.h"
#include <wtf/HashMap.h>
#include <wtf/Vector.h>

namespace JSC { namespace B3 {

class BasicBlock;
class Dominators;
class Value;

typedef Vector<Value*, 1> Matches;

// This is a reusable utility for doing pure CSE. You can use it to do pure CSE on a program by just
// proceeding in order and calling process().
class PureCSE {
public:
    PureCSE();
    ~PureCSE();

    void clear();

    Value* findMatch(const ValueKey&, BasicBlock*, Dominators&);

    bool process(Value*, Dominators&);
    
private:
    HashMap<ValueKey, Matches> m_map;
};

bool pureCSE(Procedure&);

} } // namespace JSC::B3

#endif // ENABLE(B3_JIT)