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 8080156 8060036
27 * @summary Test correctness of type propagation to CmpUNodes.
28 *
29 * @run main compiler.types.TestTypePropagationToCmpU
30 */
31
32package compiler.types;
33
34public class TestTypePropagationToCmpU {
35    public static void main(String[] args) {
36        try {
37            // Trigger compilation
38            for (int i = 0; i < 100_000; ++i) {
39                test();
40            }
41        } catch (NullPointerException e) {
42            // Test should never throw a NullPointerException
43            throw new RuntimeException("Test failed");
44        }
45    }
46
47    static int global = 42;
48
49    public static void test() {
50        int a = Integer.MIN_VALUE;
51        int b = global;
52        char[] buf = { 0 };
53        for (int i = 0; i <= b; ++i) {
54            a = i - b;
55        }
56        // C2 adds a range check and an uncommon trap here to ensure that the array index
57        // is in bounds. If type information is not propagated correctly to the corresponding
58        // CmpUNode, this trap may be always taken. Because C2 also removes the unnecessary
59        // allocation of 'buf', a NullPointerException is thrown in this case.
60        char c = buf[(a * 11) / 2 - a]; // a is 0 here if global >= 0
61        buf[0] = 0;
62    }
63}
64