
This patch adds a `-z` option to js and test-js. When run in this mode, garbage cells are never actually destroyed. We instead keep them around in a special zombie state. This allows us to validate that zombies don't get marked in future GC scans (since there were not supposed to be any more references!) :^) Cells get notified when they become a zombie (via did_become_zombie()) and this is used by WeakContainer cells to deregister themselves from the heap.
40 lines
943 B
C++
40 lines
943 B
C++
/*
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* Copyright (c) 2021, Idan Horowitz <idan.horowitz@serenityos.org>
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*
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* SPDX-License-Identifier: BSD-2-Clause
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*/
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#pragma once
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#include <LibJS/Runtime/GlobalObject.h>
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#include <LibJS/Runtime/Object.h>
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#include <LibJS/Runtime/WeakContainer.h>
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namespace JS {
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class WeakRef final
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: public Object
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, public WeakContainer {
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JS_OBJECT(WeakRef, Object);
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public:
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static WeakRef* create(GlobalObject&, Object*);
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explicit WeakRef(Object*, Object& prototype);
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virtual ~WeakRef() override;
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Object* value() const { return m_value; };
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void update_execution_generation() { m_last_execution_generation = vm().execution_generation(); };
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virtual void remove_swept_cells(Badge<Heap>, Span<Cell*>) override;
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private:
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virtual void visit_edges(Visitor&) override;
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virtual void did_become_zombie() override { deregister(); }
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Object* m_value { nullptr };
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u32 m_last_execution_generation { 0 };
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};
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}
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