darling-JavaScriptCore/bytecode/LLIntCallLinkInfo.h
2020-08-29 15:28:47 -04:00

97 lines
3.1 KiB
C++

/*
* Copyright (C) 2012-2018 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
#include "JSCPtrTag.h"
#include "JSFunction.h"
#include "MacroAssemblerCodeRef.h"
#include <wtf/SentinelLinkedList.h>
namespace JSC {
struct Instruction;
class LLIntCallLinkInfo : public PackedRawSentinelNode<LLIntCallLinkInfo> {
public:
friend class LLIntOffsetsExtractor;
static constexpr uintptr_t unlinkedBit = 0x1;
LLIntCallLinkInfo() = default;
~LLIntCallLinkInfo()
{
if (isOnList())
remove();
}
bool isLinked() const { return !(m_calleeOrLastSeenCalleeWithLinkBit & unlinkedBit); }
void link(VM& vm, JSCell* owner, JSObject* callee, MacroAssemblerCodePtr<JSEntryPtrTag> codePtr)
{
if (isOnList())
remove();
m_calleeOrLastSeenCalleeWithLinkBit = bitwise_cast<uintptr_t>(callee);
vm.heap.writeBarrier(owner, callee);
m_machineCodeTarget = codePtr;
}
void unlink()
{
// Make link invalidated. It works because LLInt tests the given callee with this pointer. But it is still valid as lastSeenCallee!
m_calleeOrLastSeenCalleeWithLinkBit |= unlinkedBit;
m_machineCodeTarget = MacroAssemblerCodePtr<JSEntryPtrTag>();
if (isOnList())
remove();
}
JSObject* callee() const
{
if (!isLinked())
return nullptr;
return bitwise_cast<JSObject*>(m_calleeOrLastSeenCalleeWithLinkBit);
}
JSObject* lastSeenCallee() const
{
return bitwise_cast<JSObject*>(m_calleeOrLastSeenCalleeWithLinkBit & ~unlinkedBit);
}
void clearLastSeenCallee()
{
m_calleeOrLastSeenCalleeWithLinkBit = unlinkedBit;
}
ArrayProfile m_arrayProfile;
private:
uintptr_t m_calleeOrLastSeenCalleeWithLinkBit { unlinkedBit };
MacroAssemblerCodePtr<JSEntryPtrTag> m_machineCodeTarget;
};
} // namespace JSC