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test/compiler/unsafe/GetUnsafeObjectG1PreBarrier.java@710a3c8b516e (annotated)

test/compiler/unsafe/GetUnsafeObjectG1PreBarrier.java

Tue, 08 Aug 2017 15:57:29 +0800

author

aoqi

date

Tue, 08 Aug 2017 15:57:29 +0800

changeset 6876

710a3c8b516e

parent 5490

71526a36ebb4

parent 0

f90c822e73f8

permissions

-rw-r--r--

merge

aoqi@0	1	/*
aoqi@0	2	* Copyright (c) 2013, Oracle and/or its affiliates. All rights reserved.
aoqi@0	3	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
aoqi@0	4	*
aoqi@0	5	* This code is free software; you can redistribute it and/or modify it
aoqi@0	6	* under the terms of the GNU General Public License version 2 only, as
aoqi@0	7	* published by the Free Software Foundation.
aoqi@0	8	*
aoqi@0	9	* This code is distributed in the hope that it will be useful, but WITHOUT
aoqi@0	10	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
aoqi@0	11	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
aoqi@0	12	* version 2 for more details (a copy is included in the LICENSE file that
aoqi@0	13	* accompanied this code).
aoqi@0	14	*
aoqi@0	15	* You should have received a copy of the GNU General Public License version
aoqi@0	16	* 2 along with this work; if not, write to the Free Software Foundation,
aoqi@0	17	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
aoqi@0	18	*
aoqi@0	19	* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
aoqi@0	20	* or visit www.oracle.com if you need additional information or have any
aoqi@0	21	* questions.
aoqi@0	22	*/
aoqi@0	23
aoqi@0	24	/*
aoqi@0	25	* @test
aoqi@0	26	* @bug 8016474
aoqi@0	27	* @summary The bug only happens with C1 and G1 using a different ObjectAlignmentInBytes than KlassAlignmentInBytes (which is 8)
aoqi@0	28	* @run main/othervm -Xbatch -XX:+IgnoreUnrecognizedVMOptions -XX:ObjectAlignmentInBytes=32 GetUnsafeObjectG1PreBarrier
aoqi@0	29	*/
aoqi@0	30
aoqi@0	31	import java.lang.reflect.Field;
aoqi@0	32
aoqi@0	33	import sun.misc.Unsafe;
aoqi@0	34
aoqi@0	35	public class GetUnsafeObjectG1PreBarrier {
aoqi@0	36	private static final Unsafe unsafe;
aoqi@0	37	private static final int N = 100_000;
aoqi@0	38
aoqi@0	39	static {
aoqi@0	40	try {
aoqi@0	41	Field theUnsafe = Unsafe.class.getDeclaredField("theUnsafe");
aoqi@0	42	theUnsafe.setAccessible(true);
aoqi@0	43	unsafe = (Unsafe) theUnsafe.get(null);
aoqi@0	44	} catch (NoSuchFieldException | IllegalAccessException e) {
aoqi@0	45	throw new IllegalStateException(e);
aoqi@0	46	}
aoqi@0	47	}
aoqi@0	48
aoqi@0	49	public Object a;
aoqi@0	50
aoqi@0	51	public static void main(String[] args) throws Throwable {
aoqi@0	52	new GetUnsafeObjectG1PreBarrier();
aoqi@0	53	}
aoqi@0	54
aoqi@0	55	public GetUnsafeObjectG1PreBarrier() throws Throwable {
aoqi@0	56	doit();
aoqi@0	57	}
aoqi@0	58
aoqi@0	59	private void doit() throws Throwable {
aoqi@0	60	Field field = GetUnsafeObjectG1PreBarrier.class.getField("a");
aoqi@0	61	long fieldOffset = unsafe.objectFieldOffset(field);
aoqi@0	62
aoqi@0	63	for (int i = 0; i < N; i++) {
aoqi@0	64	readField(this, fieldOffset);
aoqi@0	65	}
aoqi@0	66	}
aoqi@0	67
aoqi@0	68	private void readField(Object o, long fieldOffset) {
aoqi@0	69	unsafe.getObject(o, fieldOffset);
aoqi@0	70	}
aoqi@0	71	}