darling-JavaScriptCore/runtime/WeakMapImpl.cpp

118 lines
4.2 KiB
C++

/*
* Copyright (C) 2017 Apple Inc. All rights reserved.
* Copyright (C) 2017 Yusuke Suzuki <utatane.tea@gmail.com>.
*
* 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.
*/
#include "config.h"
#include "WeakMapImpl.h"
#include "AuxiliaryBarrierInlines.h"
#include "StructureInlines.h"
#include "WeakMapImplInlines.h"
namespace JSC {
template <typename WeakMapBucket>
void WeakMapImpl<WeakMapBucket>::destroy(JSCell* cell)
{
static_cast<WeakMapImpl*>(cell)->~WeakMapImpl();
}
template <typename WeakMapBucket>
void WeakMapImpl<WeakMapBucket>::visitChildren(JSCell* cell, SlotVisitor& visitor)
{
WeakMapImpl* thisObject = jsCast<WeakMapImpl*>(cell);
ASSERT_GC_OBJECT_INHERITS(thisObject, info());
Base::visitChildren(thisObject, visitor);
visitor.reportExtraMemoryVisited(thisObject->m_capacity * sizeof(WeakMapBucket));
}
template <typename WeakMapBucket>
size_t WeakMapImpl<WeakMapBucket>::estimatedSize(JSCell* cell, VM& vm)
{
auto* thisObject = static_cast<WeakMapImpl*>(cell);
return Base::estimatedSize(thisObject, vm) + (sizeof(WeakMapImpl) - sizeof(Base)) + thisObject->m_capacity * sizeof(WeakMapBucket);
}
template <>
void WeakMapImpl<WeakMapBucket<WeakMapBucketDataKey>>::visitOutputConstraints(JSCell*, SlotVisitor&)
{
// Only JSWeakMap needs to harvest value references
}
template <>
void WeakMapImpl<WeakMapBucket<WeakMapBucketDataKeyValue>>::visitOutputConstraints(JSCell* cell, SlotVisitor& visitor)
{
VM& vm = visitor.vm();
auto* thisObject = jsCast<WeakMapImpl*>(cell);
auto locker = holdLock(thisObject->cellLock());
auto* buffer = thisObject->buffer();
for (uint32_t index = 0; index < thisObject->m_capacity; ++index) {
auto* bucket = buffer + index;
if (bucket->isEmpty() || bucket->isDeleted())
continue;
if (!vm.heap.isMarked(bucket->key()))
continue;
bucket->visitAggregate(visitor);
}
}
template <typename WeakMapBucket>
template<typename Appender>
void WeakMapImpl<WeakMapBucket>::takeSnapshotInternal(unsigned limit, Appender appender)
{
DisallowGC disallowGC;
unsigned fetched = 0;
forEach([&] (JSObject* key, JSValue value) {
appender(key, value);
++fetched;
if (limit && fetched >= limit)
return IterationState::Stop;
return IterationState::Continue;
});
}
// takeSnapshot must not invoke garbage collection since iterating WeakMap may be modified.
template <>
void WeakMapImpl<WeakMapBucket<WeakMapBucketDataKey>>::takeSnapshot(MarkedArgumentBuffer& buffer, unsigned limit)
{
takeSnapshotInternal(limit, [&] (JSObject* key, JSValue) {
buffer.append(key);
});
}
template <>
void WeakMapImpl<WeakMapBucket<WeakMapBucketDataKeyValue>>::takeSnapshot(MarkedArgumentBuffer& buffer, unsigned limit)
{
takeSnapshotInternal(limit, [&] (JSObject* key, JSValue value) {
buffer.append(key);
buffer.append(value);
});
}
template class WeakMapImpl<WeakMapBucket<WeakMapBucketDataKeyValue>>;
template class WeakMapImpl<WeakMapBucket<WeakMapBucketDataKey>>;
} // namespace JSC