1/*
2 * Copyright (c) 2015, Oracle and/or its affiliates. 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 8086046
27 * @summary load bypasses arraycopy that sets the value after the ArrayCopyNode is expanded
28 *
29 * @run main/othervm -XX:-BackgroundCompilation  -XX:-UseOnStackReplacement
30 *                   -XX:CompileCommand=dontinline,compiler.arraycopy.TestLoadBypassArrayCopy::test_helper
31 *                   -XX:-TieredCompilation
32 *                   compiler.arraycopy.TestLoadBypassArrayCopy
33 */
34
35package compiler.arraycopy;
36
37public class TestLoadBypassArrayCopy {
38
39    static long i;
40    static boolean test_helper() {
41        i++;
42        if ((i%10) == 0) {
43            return false;
44        }
45        return true;
46    }
47
48    static int test(int[] src, int len, boolean flag) {
49        int[] dest = new int[10];
50        int res = 0;
51        while (test_helper()) {
52            System.arraycopy(src, 0, dest, 0, len);
53            // predicate moved out of loop so control of following
54            // load is not the ArrayCopyNode. Otherwise, if the memory
55            // of the load is changed and the control is set to the
56            // ArrayCopyNode the graph is unschedulable and the test
57            // doesn't fail.
58            if (flag) {
59            }
60            // The memory of this load shouldn't bypass the arraycopy
61            res = dest[0];
62        }
63        return res;
64    }
65
66    static public void main(String[] args) {
67        int[] src = new int[10];
68        src[0] = 0x42;
69        for (int i = 0; i < 20000; i++) {
70            int res = test(src, 10, false);
71            if (res != src[0]) {
72                throw new RuntimeException("test failed");
73            }
74        }
75    }
76}
77