blob: 5f01f34b3a07ee2e3812d00aeda95d9d396ba5eb [file] [log] [blame]
/*
* Copyright (C) 2012 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.
*/
#include "config.h"
#include "WeakBlock.h"
#include "Heap.h"
#include "HeapRootVisitor.h"
#include "JSObject.h"
#include "Structure.h"
namespace JSC {
WeakBlock* WeakBlock::create(DeadBlock* block)
{
Region* region = block->region();
return new (NotNull, block) WeakBlock(region);
}
WeakBlock::WeakBlock(Region* region)
: HeapBlock<WeakBlock>(region)
{
for (size_t i = 0; i < weakImplCount(); ++i) {
WeakImpl* weakImpl = &weakImpls()[i];
new (NotNull, weakImpl) WeakImpl;
addToFreeList(&m_sweepResult.freeList, weakImpl);
}
ASSERT(isEmpty());
}
void WeakBlock::lastChanceToFinalize()
{
for (size_t i = 0; i < weakImplCount(); ++i) {
WeakImpl* weakImpl = &weakImpls()[i];
if (weakImpl->state() >= WeakImpl::Finalized)
continue;
weakImpl->setState(WeakImpl::Dead);
finalize(weakImpl);
}
}
void WeakBlock::sweep()
{
// If a block is completely empty, a sweep won't have any effect.
if (isEmpty())
return;
SweepResult sweepResult;
for (size_t i = 0; i < weakImplCount(); ++i) {
WeakImpl* weakImpl = &weakImpls()[i];
if (weakImpl->state() == WeakImpl::Dead)
finalize(weakImpl);
if (weakImpl->state() == WeakImpl::Deallocated)
addToFreeList(&sweepResult.freeList, weakImpl);
else
sweepResult.blockIsFree = false;
}
m_sweepResult = sweepResult;
ASSERT(!m_sweepResult.isNull());
}
void WeakBlock::visit(HeapRootVisitor& heapRootVisitor)
{
// If a block is completely empty, a visit won't have any effect.
if (isEmpty())
return;
SlotVisitor& visitor = heapRootVisitor.visitor();
for (size_t i = 0; i < weakImplCount(); ++i) {
WeakImpl* weakImpl = &weakImpls()[i];
if (weakImpl->state() != WeakImpl::Live)
continue;
const JSValue& jsValue = weakImpl->jsValue();
if (Heap::isLive(jsValue.asCell()))
continue;
WeakHandleOwner* weakHandleOwner = weakImpl->weakHandleOwner();
if (!weakHandleOwner)
continue;
if (!weakHandleOwner->isReachableFromOpaqueRoots(Handle<Unknown>::wrapSlot(&const_cast<JSValue&>(jsValue)), weakImpl->context(), visitor))
continue;
heapRootVisitor.visit(&const_cast<JSValue&>(jsValue));
}
}
void WeakBlock::reap()
{
// If a block is completely empty, a reaping won't have any effect.
if (isEmpty())
return;
for (size_t i = 0; i < weakImplCount(); ++i) {
WeakImpl* weakImpl = &weakImpls()[i];
if (weakImpl->state() > WeakImpl::Dead)
continue;
if (Heap::isLive(weakImpl->jsValue().asCell())) {
ASSERT(weakImpl->state() == WeakImpl::Live);
continue;
}
weakImpl->setState(WeakImpl::Dead);
}
}
} // namespace JSC