1/*
2 * Copyright (c) 2017, Red Hat, Inc. 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 8181742
27 * @summary Loads that bypass arraycopy ends up with wrong memory state
28 *
29 * @run main/othervm -XX:-BackgroundCompilation -XX:-UseOnStackReplacement -XX:+UnlockDiagnosticVMOptions -XX:+IgnoreUnrecognizedVMOptions -XX:+StressGCM -XX:+StressLCM TestLoadBypassACWithWrongMem
30 *
31 */
32
33import java.util.Arrays;
34
35public class TestLoadBypassACWithWrongMem {
36
37    static int test1(int[] src) {
38        int[] dst = new int[10];
39        System.arraycopy(src, 0, dst, 0, 10);
40        src[1] = 0x42;
41        // dst[1] is transformed to src[1], src[1] must use the
42        // correct memory state (not the store above).
43        return dst[1];
44    }
45
46    static int test2(int[] src) {
47        int[] dst = (int[])src.clone();
48        src[1] = 0x42;
49        // Same as above for clone
50        return dst[1];
51    }
52
53    static Object test5_src = null;
54    static int test3() {
55        int[] dst = new int[10];
56        System.arraycopy(test5_src, 0, dst, 0, 10);
57        ((int[])test5_src)[1] = 0x42;
58        System.arraycopy(test5_src, 0, dst, 0, 10);
59        // dst[1] is transformed to test5_src[1]. test5_src is Object
60        // but test5_src[1] must be on the slice for int[] not
61        // Object+some offset.
62        return dst[1];
63    }
64
65    static public void main(String[] args) {
66        int[] src = new int[10];
67        for (int i = 0; i < 20000; i++) {
68            Arrays.fill(src, 0);
69            int res = test1(src);
70            if (res != 0) {
71                throw new RuntimeException("bad result: " + res + " != " + 0);
72            }
73            Arrays.fill(src, 0);
74            res = test2(src);
75            if (res != 0) {
76                throw new RuntimeException("bad result: " + res + " != " + 0);
77            }
78            Arrays.fill(src, 0);
79            test5_src = src;
80            res = test3();
81            if (res != 0x42) {
82                throw new RuntimeException("bad result: " + res + " != " + 0x42);
83            }
84         }
85    }
86}
87