src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/gc/z/ZPageTableEntry.java
author stefank
Tue, 19 Feb 2019 10:04:28 +0100
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permissions -rw-r--r--
8218922: SA: Enable best-effort implementation of live regions iteration for ZGC Reviewed-by: eosterlund, ysuenaga
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/*
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 * Copyright (c) 2018, 2019, 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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package sun.jvm.hotspot.gc.z;
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import sun.jvm.hotspot.debugger.Address;
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import sun.jvm.hotspot.runtime.VMObjectFactory;
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class ZPageTableEntry {
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    Address entry;
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    ZPageTableEntry(Address address) {
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        entry = address;
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    }
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    ZPage page() {
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        return (ZPage)VMObjectFactory.newObject(ZPage.class, zPageBits());
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    }
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    private Address zPageBits() {
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        return entry.andWithMask(~1L);
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    }
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    boolean relocating() {
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        return (entry.asLongValue() & 1) == 1;
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    }
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    boolean isEmpty() {
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        return entry == null || zPageBits() == null;
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    }
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}