mirror of
https://github.com/darlinghq/darling-JavaScriptCore.git
synced 2025-04-09 02:10:43 +00:00
84 lines
2.8 KiB
C++
84 lines
2.8 KiB
C++
/*
|
|
* Copyright (C) 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. ``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 "JSObject.h"
|
|
|
|
namespace JSC {
|
|
|
|
class JSWeakObjectRef final : public JSNonFinalObject {
|
|
public:
|
|
using Base = JSNonFinalObject;
|
|
|
|
DECLARE_EXPORT_INFO;
|
|
|
|
static Structure* createStructure(VM& vm, JSGlobalObject* globalObject, JSValue prototype)
|
|
{
|
|
return Structure::create(vm, globalObject, prototype, TypeInfo(ObjectType, StructureFlags), info());
|
|
}
|
|
|
|
static JSWeakObjectRef* create(VM& vm, Structure* structure, JSObject* target)
|
|
{
|
|
JSWeakObjectRef* instance = new (NotNull, allocateCell<JSWeakObjectRef>(vm.heap)) JSWeakObjectRef(vm, structure);
|
|
instance->finishCreation(vm, target);
|
|
return instance;
|
|
}
|
|
|
|
JSObject* deref(VM& vm)
|
|
{
|
|
if (m_value && vm.currentWeakRefVersion() != m_lastAccessVersion) {
|
|
m_lastAccessVersion = vm.currentWeakRefVersion();
|
|
// Perform a GC barrier here so we rescan this object and keep the object alive if we wouldn't otherwise.
|
|
vm.heap.writeBarrier(this);
|
|
}
|
|
|
|
return m_value.get();
|
|
}
|
|
|
|
template<typename CellType, SubspaceAccess mode>
|
|
static IsoSubspace* subspaceFor(VM& vm)
|
|
{
|
|
return vm.weakObjectRefSpace<mode>();
|
|
}
|
|
|
|
void finalizeUnconditionally(VM&);
|
|
static void visitChildren(JSCell*, SlotVisitor&);
|
|
|
|
private:
|
|
JSWeakObjectRef(VM& vm, Structure* structure)
|
|
: Base(vm, structure)
|
|
{
|
|
}
|
|
|
|
JS_EXPORT_PRIVATE void finishCreation(VM&, JSObject* value);
|
|
|
|
uintptr_t m_lastAccessVersion;
|
|
WriteBarrier<JSObject> m_value;
|
|
};
|
|
|
|
} // namespace JSC
|
|
|