31 lines
804 B
C
31 lines
804 B
C
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// Copyright 2020 the V8 project authors. All rights reserved.
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// Use of this source code is governed by a BSD-style license that can be
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// found in the LICENSE file.
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#ifndef INCLUDE_CPPGC_EPHEMERON_PAIR_H_
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#define INCLUDE_CPPGC_EPHEMERON_PAIR_H_
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#include "cppgc/liveness-broker.h"
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#include "cppgc/member.h"
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namespace cppgc {
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/**
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* An ephemeron pair is used to conditionally retain an object.
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* The `value` will be kept alive only if the `key` is alive.
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*/
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template <typename K, typename V>
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struct EphemeronPair {
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EphemeronPair(K* k, V* v) : key(k), value(v) {}
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WeakMember<K> key;
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Member<V> value;
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void ClearValueIfKeyIsDead(const LivenessBroker& broker) {
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if (!broker.IsHeapObjectAlive(key)) value = nullptr;
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}
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};
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} // namespace cppgc
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#endif // INCLUDE_CPPGC_EPHEMERON_PAIR_H_
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