darling-JavaScriptCore/heap/WeakSet.h

136 lines
3.7 KiB
C++

/*
* Copyright (C) 2012-2019 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. AND ITS CONTRIBUTORS ``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 ITS 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 "CellContainer.h"
#include "WeakBlock.h"
#include <wtf/SentinelLinkedList.h>
namespace JSC {
class Heap;
class WeakImpl;
class WeakSet : public BasicRawSentinelNode<WeakSet> {
friend class LLIntOffsetsExtractor;
public:
static WeakImpl* allocate(JSValue, WeakHandleOwner* = nullptr, void* context = nullptr);
static void deallocate(WeakImpl*);
WeakSet(VM&);
~WeakSet();
void lastChanceToFinalize();
Heap* heap() const;
VM& vm() const;
bool isEmpty() const;
bool isTriviallyDestructible() const;
void visit(SlotVisitor&);
void reap();
void sweep();
void shrink();
void resetAllocator();
static ptrdiff_t offsetOfVM() { return OBJECT_OFFSETOF(WeakSet, m_vm); }
private:
JS_EXPORT_PRIVATE WeakBlock::FreeCell* findAllocator(CellContainer);
WeakBlock::FreeCell* tryFindAllocator();
WeakBlock::FreeCell* addAllocator(CellContainer);
void removeAllocator(WeakBlock*);
WeakBlock::FreeCell* m_allocator { nullptr };
WeakBlock* m_nextAllocator { nullptr };
DoublyLinkedList<WeakBlock> m_blocks;
// m_vm must be a pointer (instead of a reference) because the JSCLLIntOffsetsExtractor
// cannot handle it being a reference.
VM* m_vm;
};
inline WeakSet::WeakSet(VM& vm)
: m_vm(&vm)
{
}
inline VM& WeakSet::vm() const
{
return *m_vm;
}
inline bool WeakSet::isEmpty() const
{
for (WeakBlock* block = m_blocks.head(); block; block = block->next()) {
if (!block->isEmpty())
return false;
}
return true;
}
inline bool WeakSet::isTriviallyDestructible() const
{
if (!m_blocks.isEmpty())
return false;
if (isOnList())
return false;
return true;
}
inline void WeakSet::deallocate(WeakImpl* weakImpl)
{
weakImpl->setState(WeakImpl::Deallocated);
}
inline void WeakSet::lastChanceToFinalize()
{
for (WeakBlock* block = m_blocks.head(); block; block = block->next())
block->lastChanceToFinalize();
}
inline void WeakSet::visit(SlotVisitor& visitor)
{
for (WeakBlock* block = m_blocks.head(); block; block = block->next())
block->visit(visitor);
}
inline void WeakSet::reap()
{
for (WeakBlock* block = m_blocks.head(); block; block = block->next())
block->reap();
}
inline void WeakSet::resetAllocator()
{
m_allocator = nullptr;
m_nextAllocator = m_blocks.head();
}
} // namespace JSC