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 /**

    26  * @test

    27  * @bug 8072753

    28  * @summary Inner loop induction variable increment occurs before compare which causes integer overflow

    29  * @run main/othervm CountedLoopProblem

    30  *

    31  */

    32 

    33 import java.util.*;

    34 

    35 public class CountedLoopProblem {

    36     public static void main(String[] args) throws Exception {

    37         Random r = new Random(42);

    38         int x = 0;

    39         StringBuilder sb = new StringBuilder();

    40         for(int i = 0; i < 1000000; ++i) {

    41             int v = Math.abs(r.nextInt());

    42             sb.append('+').append(v).append('\n');

    43             x += v;

    44             // To trigger the problem we must OSR in the following loop

    45             // To make the problem 100% reproducible run with -XX:-TieredCompilation -XX:OSROnlyBCI=62

    46             while(x < 0) x += 1000000000;

    47             sb.append('=').append(x).append('\n');

    48         }

    49         if (sb.toString().hashCode() != 0xaba94591) {

    50             throw new Exception("Unexpected result");

    51         }

    52     }

    53 }

    54