1 /*
2 * Copyright (c) 2013 SAP SE. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 */
23
24 /**
25 * @test
26 * @bug 8007898
27 * @summary Incorrect optimization of Memory Barriers in Matcher::post_store_load_barrier().
28 * @run main/othervm -Xbatch -XX:+IgnoreUnrecognizedVMOptions -XX:-TieredCompilation
29 * -XX:CICompilerCount=1 -XX:+StressGCM -XX:+StressLCM
30 * compiler.membars.DekkerTest
31 * @run main/othervm -Xbatch -XX:+IgnoreUnrecognizedVMOptions -XX:-TieredCompilation
32 * -XX:CICompilerCount=1 -XX:+StressGCM -XX:+StressLCM
33 * compiler.membars.DekkerTest
34 * @run main/othervm -Xbatch -XX:+IgnoreUnrecognizedVMOptions -XX:-TieredCompilation
35 * -XX:CICompilerCount=1 -XX:+StressGCM -XX:+StressLCM
36 * compiler.membars.DekkerTest
37 * @author Martin Doerr martin DOT doerr AT sap DOT com
38 *
39 * Run 3 times since the failure is intermittent.
40 */
41
42 package compiler.membars;
43
44 public class DekkerTest {
45
46 /*
47 Read After Write Test (basically a simple Dekker test with volatile variables)
48 Derived from the original jcstress test, available at:
49 http://hg.openjdk.java.net/code-tools/jcstress/file/6c339a5aa00d/
50 tests-custom/src/main/java/org/openjdk/jcstress/tests/volatiles/DekkerTest.java
51 */
52
53 static final int ITERATIONS = 1000000;
54
55 static class TestData {
56 public volatile int a;
57 public volatile int b;
58 }
59
60 static class ResultData {
61 public int a;
62 public int b;
63 }
64
65 TestData[] testDataArray;
66 ResultData[] results;
67
68 volatile boolean start;
69
70 public DekkerTest() {
71 testDataArray = new TestData[ITERATIONS];
72 results = new ResultData[ITERATIONS];
73 for (int i = 0; i < ITERATIONS; ++i) {
74 testDataArray[i] = new TestData();
75 results[i] = new ResultData();
76 }
77 start = false;
78 }
79
80 public void reset() {
81 for (int i = 0; i < ITERATIONS; ++i) {
82 testDataArray[i].a = 0;
83 testDataArray[i].b = 0;
84 results[i].a = 0;
85 results[i].b = 0;
86 }
87 start = false;
88 }
89
90 int actor1(TestData t) {
91 t.a = 1;
92 return t.b;
93 }
94
95 int actor2(TestData t) {
96 t.b = 1;
97 return t.a;
98 }
99
100 class Runner1 extends Thread {
101 public void run() {
102 do {} while (!start);
103 for (int i = 0; i < ITERATIONS; ++i) {
104 results[i].a = actor1(testDataArray[i]);
105 }
106 }
107 }
108
109 class Runner2 extends Thread {
110 public void run() {
111 do {} while (!start);
112 for (int i = 0; i < ITERATIONS; ++i) {
113 results[i].b = actor2(testDataArray[i]);
114 }
115 }
116 }
117
118 void testRunner() {
119 Thread thread1 = new Runner1();
120 Thread thread2 = new Runner2();
121 thread1.start();
122 thread2.start();
123 do {} while (!thread1.isAlive());
124 do {} while (!thread2.isAlive());
125 start = true;
126 Thread.yield();
127 try {
128 thread1.join();
129 thread2.join();
130 } catch (InterruptedException e) {
131 System.out.println("interrupted!");
132 System.exit(1);
133 }
134 }
135
136 boolean printResult() {
137 int[] count = new int[4];
138 for (int i = 0; i < ITERATIONS; ++i) {
139 int event_kind = (results[i].a << 1) + results[i].b;
140 ++count[event_kind];
141 }
142 if (count[0] == 0 && count[3] == 0) {
143 System.out.println("[not interesting]");
144 return false; // not interesting
145 }
146 String error = (count[0] == 0) ? " ok" : " disallowed!";
147 System.out.println("[0,0] " + count[0] + error);
148 System.out.println("[0,1] " + count[1]);
149 System.out.println("[1,0] " + count[2]);
150 System.out.println("[1,1] " + count[3]);
151 return (count[0] != 0);
152 }
153
154 public static void main(String args[]) {
155 DekkerTest test = new DekkerTest();
156 final int runs = 30;
157 int failed = 0;
158 for (int c = 0; c < runs; ++c) {
159 test.testRunner();
160 if (test.printResult()) {
161 failed++;
162 }
163 test.reset();
164 }
165 if (failed > 0) {
166 throw new InternalError("FAILED. Got " + failed + " failed ITERATIONS");
167 }
168 System.out.println("PASSED.");
169 }
170
171 }