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/*
* Copyright (c) 2021, Idan Horowitz <idan.horowitz@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <LibJS/Runtime/WeakRef.h>
namespace JS {
WeakRef* WeakRef::create(GlobalObject& global_object, Object* object)
{
return global_object.heap().allocate<WeakRef>(global_object, object, *global_object.weak_ref_prototype());
}
WeakRef::WeakRef(Object* object, Object& prototype)
: Object(prototype)
, WeakContainer(heap())
, m_value(object)
, m_last_execution_generation(vm().execution_generation())
{
}
WeakRef::~WeakRef()
{
}
void WeakRef::remove_swept_cells(Badge<Heap>, Vector<Cell*>& cells)
{
VERIFY(m_value);
for (auto* cell : cells) {
if (m_value != cell)
continue;
m_value = nullptr;
// This is an optimization, we deregister from the garbage collector early (even if we were not garbage collected ourself yet)
// to reduce the garbage collection overhead, which we can do because a cleared weak ref cannot be reused.
WeakContainer::deregister();
break;
}
}
void WeakRef::visit_edges(Visitor& visitor)
{
Object::visit_edges(visitor);
if (vm().execution_generation() == m_last_execution_generation)
visitor.visit(m_value);
}
}
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