src/hotspot/share/gc/shared/accessBarrierSupport.hpp
author sjohanss
Wed, 02 May 2018 13:44:49 +0200
changeset 49946 2143feab681a
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child 53244 9807daeb47c4
permissions -rw-r--r--
8202140: TLAB logging is not correct for G1 Reviewed-by: tschatzl, sangheki
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/*
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 * Copyright (c) 2017, Oracle and/or its affiliates. All rights reserved.
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 *
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 * This code is free software; you can redistribute it and/or modify it
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 * under the terms of the GNU General Public License version 2 only, as
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 * published by the Free Software Foundation.
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 *
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 * This code is distributed in the hope that it will be useful, but WITHOUT
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 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
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 * version 2 for more details (a copy is included in the LICENSE file that
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 * accompanied this code).
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 *
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 * You should have received a copy of the GNU General Public License version
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 * 2 along with this work; if not, write to the Free Software Foundation,
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 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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 *
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 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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 * or visit www.oracle.com if you need additional information or have any
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 * questions.
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 *
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 */
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#ifndef SHARE_VM_GC_SHARED_ACCESSBARRIERSUPPORT_HPP
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#define SHARE_VM_GC_SHARED_ACCESSBARRIERSUPPORT_HPP
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#include "memory/allocation.hpp"
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#include "oops/access.hpp"
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class AccessBarrierSupport: AllStatic {
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private:
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  static DecoratorSet resolve_unknown_oop_ref_strength(DecoratorSet decorators, oop base, ptrdiff_t offset);
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public:
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  // Some collectors, like G1, needs to keep referents alive when loading them.
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  // Therefore, for APIs that accept unknown oop ref strength (e.g. unsafe),
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  // we need to dynamically find out if a given field is on a java.lang.ref.Reference object.
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  // and in that case what strength it has.
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  template<DecoratorSet decorators>
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  static DecoratorSet resolve_possibly_unknown_oop_ref_strength(oop base, ptrdiff_t offset);
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};
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#endif // SHARE_VM_GC_SHARED_ACCESSBARRIERSUPPORT_HPP