77 lines
2.5 KiB
Java
77 lines
2.5 KiB
Java
/*
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* Copyright (c) 2013, 2015, 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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* @test
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* @bug 8016474
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* @summary The bug only happens with C1 and G1 using a different ObjectAlignmentInBytes than KlassAlignmentInBytes (which is 8)
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*
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* @modules java.base/jdk.internal.misc:+open
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* @run main/othervm -Xbatch -XX:+IgnoreUnrecognizedVMOptions -XX:ObjectAlignmentInBytes=32
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* compiler.unsafe.GetUnsafeObjectG1PreBarrier
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*/
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package compiler.unsafe;
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import jdk.internal.misc.Unsafe;
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import java.lang.reflect.Field;
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public class GetUnsafeObjectG1PreBarrier {
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private static final Unsafe unsafe;
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private static final int N = 100_000;
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static {
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try {
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Field theUnsafe = Unsafe.class.getDeclaredField("theUnsafe");
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theUnsafe.setAccessible(true);
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unsafe = (Unsafe) theUnsafe.get(null);
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} catch (NoSuchFieldException | IllegalAccessException e) {
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throw new IllegalStateException(e);
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}
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}
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public Object a;
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public static void main(String[] args) throws Throwable {
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new GetUnsafeObjectG1PreBarrier();
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}
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public GetUnsafeObjectG1PreBarrier() throws Throwable {
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doit();
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}
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private void doit() throws Throwable {
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Field field = GetUnsafeObjectG1PreBarrier.class.getField("a");
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long fieldOffset = unsafe.objectFieldOffset(field);
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for (int i = 0; i < N; i++) {
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readField(this, fieldOffset);
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}
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}
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private void readField(Object o, long fieldOffset) {
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unsafe.getReference(o, fieldOffset);
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}
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}
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