Source/JavaScriptCore/dfg/DFGUseKind.h

/*
 * Copyright (C) 2013, 2014 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
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 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
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 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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 */

#ifndef DFGUseKind_h
#define DFGUseKind_h

#if ENABLE(DFG_JIT)

#include "SpeculatedType.h"
#include <wtf/PrintStream.h>

namespace JSC { namespace DFG {

enum UseKind {
    UntypedUse,
    Int32Use,
    KnownInt32Use,
    MachineIntUse,
    RealNumberUse,
    NumberUse,
    KnownNumberUse,
    BooleanUse,
    CellUse,
    KnownCellUse,
    ObjectUse,
    FinalObjectUse,
    ObjectOrOtherUse,
    StringIdentUse,
    StringUse,
    KnownStringUse,
    StringObjectUse,
    StringOrStringObjectUse,
    NotCellUse,
    OtherUse,
    MiscUse,
    LastUseKind // Must always be the last entry in the enum, as it is used to denote the number of enum elements.
};

ALWAYS_INLINE SpeculatedType typeFilterFor(UseKind useKind)
{
    switch (useKind) {
    case UntypedUse:
        return SpecFullTop;
    case Int32Use:
    case KnownInt32Use:
        return SpecInt32;
    case MachineIntUse:
        return SpecMachineInt;
    case RealNumberUse:
        return SpecFullRealNumber;
    case NumberUse:
    case KnownNumberUse:
        return SpecFullNumber;
    case BooleanUse:
        return SpecBoolean;
    case CellUse:
    case KnownCellUse:
        return SpecCell;
    case ObjectUse:
        return SpecObject;
    case FinalObjectUse:
        return SpecFinalObject;
    case ObjectOrOtherUse:
        return SpecObject | SpecOther;
    case StringIdentUse:
        return SpecStringIdent;
    case StringUse:
    case KnownStringUse:
        return SpecString;
    case StringObjectUse:
        return SpecStringObject;
    case StringOrStringObjectUse:
        return SpecString | SpecStringObject;
    case NotCellUse:
        return ~SpecCell;
    case OtherUse:
        return SpecOther;
    case MiscUse:
        return SpecMisc;
    default:
        RELEASE_ASSERT_NOT_REACHED();
        return SpecFullTop;
    }
}

ALWAYS_INLINE bool shouldNotHaveTypeCheck(UseKind kind)
{
    switch (kind) {
    case UntypedUse:
    case KnownInt32Use:
    case KnownNumberUse:
    case KnownCellUse:
    case KnownStringUse:
        return true;
    default:
        return false;
    }
}

ALWAYS_INLINE bool mayHaveTypeCheck(UseKind kind)
{
    return !shouldNotHaveTypeCheck(kind);
}

ALWAYS_INLINE bool isNumerical(UseKind kind)
{
    switch (kind) {
    case Int32Use:
    case KnownInt32Use:
    case MachineIntUse:
    case RealNumberUse:
    case NumberUse:
    case KnownNumberUse:
        return true;
    default:
        return false;
    }
}

ALWAYS_INLINE bool isDouble(UseKind kind)
{
    switch (kind) {
    case RealNumberUse:
    case NumberUse:
    case KnownNumberUse:
        return true;
    default:
        return false;
    }
}

ALWAYS_INLINE bool isCell(UseKind kind)
{
    switch (kind) {
    case CellUse:
    case KnownCellUse:
    case ObjectUse:
    case FinalObjectUse:
    case StringIdentUse:
    case StringUse:
    case KnownStringUse:
    case StringObjectUse:
    case StringOrStringObjectUse:
        return true;
    default:
        return false;
    }
}

// Returns true if it uses structure in a way that could be clobbered by
// things that change the structure.
ALWAYS_INLINE bool usesStructure(UseKind kind)
{
    switch (kind) {
    case StringObjectUse:
    case StringOrStringObjectUse:
        return true;
    default:
        return false;
    }
}

} } // namespace JSC::DFG

namespace WTF {

void printInternal(PrintStream&, JSC::DFG::UseKind);

} // namespace WTF

#endif // ENABLE(DFG_JIT)

#endif // DFGUseKind_h