darling-JavaScriptCore/dfg/DFGEpoch.h

126 lines
3.0 KiB
C++

/*
* Copyright (C) 2015-2019 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 <wtf/PrintStream.h>
namespace JSC { namespace DFG {
// Utility class for epoch-based analyses.
class Epoch {
public:
Epoch()
: m_epoch(s_none)
{
}
static Epoch fromUnsigned(unsigned value)
{
Epoch result;
result.m_epoch = value;
return result;
}
unsigned toUnsigned() const
{
return m_epoch;
}
static Epoch first()
{
Epoch result;
result.m_epoch = s_first;
return result;
}
bool operator!() const
{
return m_epoch == s_none;
}
explicit operator bool() const
{
return !!*this;
}
Epoch next() const
{
Epoch result;
result.m_epoch = m_epoch + 1;
return result;
}
void bump()
{
*this = next();
}
bool operator==(const Epoch& other) const
{
return m_epoch == other.m_epoch;
}
bool operator!=(const Epoch& other) const
{
return !(*this == other);
}
bool operator<(const Epoch& other) const
{
return m_epoch < other.m_epoch;
}
bool operator>(const Epoch& other) const
{
return other < *this;
}
bool operator<=(const Epoch& other) const
{
return !(*this > other);
}
bool operator>=(const Epoch& other) const
{
return !(*this < other);
}
void dump(PrintStream&) const;
private:
static constexpr unsigned s_none = 0;
static constexpr unsigned s_first = 1;
unsigned m_epoch;
};
} } // namespace JSC::DFG
#endif // ENABLE(DFG_JIT)