109 lines
3.4 KiB
Java
109 lines
3.4 KiB
Java
/*
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* Copyright (c) 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 8077504
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* @summary Unsafe load can loose control dependency and cause crash
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* @modules java.base/jdk.internal.misc:+open
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*
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* @run main/othervm -XX:-BackgroundCompilation -XX:-UseOnStackReplacement
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* compiler.unsafe.TestUnsafeLoadControl
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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 TestUnsafeLoadControl {
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private static final Unsafe UNSAFE;
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static {
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try {
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Field unsafeField = Unsafe.class.getDeclaredField("theUnsafe");
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unsafeField.setAccessible(true);
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UNSAFE = (Unsafe) unsafeField.get(null);
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} catch(Exception e) {
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throw new RuntimeException(e);
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}
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}
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static int val;
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static void test1(int[] a, boolean[] flags, boolean flag, long j) {
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for (int i = 0; i < 10; i++) {
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if (flags[i]) {
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if (flag) {
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long address = (j << 2) + UNSAFE.ARRAY_INT_BASE_OFFSET;
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int v = UNSAFE.getInt(a, address);
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val = v;
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}
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}
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}
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}
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static int test2(int[] a, boolean[] flags, boolean flag, long j) {
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int sum = 0;
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for (int i = 0; i < 10; i++) {
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if (flags[i]) {
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if (flag) {
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long address = (j << 2) + UNSAFE.ARRAY_INT_BASE_OFFSET;
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int v = UNSAFE.getInt(a, address);
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if (v == 0) {
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sum++;
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}
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}
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}
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}
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return sum;
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}
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static public void main(String[] args) {
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boolean[] flags = new boolean[10];
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for (int i = 0; i < flags.length; i++) {
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flags[i] = true;
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}
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int[] array = new int[10];
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for (int i = 0; i < 20000; i++) {
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test1(array, flags, true, 0);
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}
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for (int i = 0; i < flags.length; i++) {
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flags[i] = false;
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}
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test1(array, flags, true, Long.MAX_VALUE/4);
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for (int i = 0; i < flags.length; i++) {
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flags[i] = true;
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}
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for (int i = 0; i < 20000; i++) {
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test2(array, flags, true, 0);
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}
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for (int i = 0; i < flags.length; i++) {
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flags[i] = false;
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}
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test2(array, flags, true, Long.MAX_VALUE/4);
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}
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}
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