| /* |
| * 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 |