Source/JavaScriptCore/b3/B3SwitchValue.h

/*
 * Copyright (C) 2015-2016 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
 * 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(B3_JIT)

#include "B3CaseCollection.h"
#include "B3SwitchCase.h"
#include "B3Value.h"

namespace JSC { namespace B3 {

class SwitchValue : public Value {
public:
    static bool accepts(Kind kind) { return kind == Switch; }

    ~SwitchValue();

    // numCaseValues() + 1 == numSuccessors().
    unsigned numCaseValues() const { return m_values.size(); }

    // The successor for this case value is at the same index.
    int64_t caseValue(unsigned index) const { return m_values[index]; }
    
    const Vector<int64_t>& caseValues() const { return m_values; }

    CaseCollection cases(const BasicBlock* owner) const { return CaseCollection(this, owner); }
    CaseCollection cases() const { return cases(owner); }

    bool hasFallThrough(const BasicBlock*) const;
    bool hasFallThrough() const;

    BasicBlock* fallThrough(const BasicBlock* owner);

    // These two functions can be called in any order.
    void setFallThrough(BasicBlock*, const FrequentedBlock&);
    void appendCase(BasicBlock*, const SwitchCase&);
    
    JS_EXPORT_PRIVATE void setFallThrough(const FrequentedBlock&);
    JS_EXPORT_PRIVATE void appendCase(const SwitchCase&);

    void dumpSuccessors(const BasicBlock*, PrintStream&) const override;

    B3_SPECIALIZE_VALUE_FOR_FIXED_CHILDREN(1)
    B3_SPECIALIZE_VALUE_FOR_FINAL_SIZE_FIXED_CHILDREN

protected:
    void dumpMeta(CommaPrinter&, PrintStream&) const override;

private:
    friend class Procedure;
    friend class Value;

    static Opcode opcodeFromConstructor(Origin, Value*) { return Switch; }
    JS_EXPORT_PRIVATE SwitchValue(Origin, Value* child);

    Vector<int64_t> m_values;
};

} } // namespace JSC::B3

#endif // ENABLE(B3_JIT)