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 try { 40 StringBuilder sb = new StringBuilder(); 41 for(int i = 0; i < 1000000; ++i) { 42 int v = Math.abs(r.nextInt()); 43 sb.append('+').append(v).append('\n'); 44 x += v; 45 // To trigger the problem we must OSR in the following loop 46 // To make the problem 100% reproducible run with -XX:-TieredCompilation -XX:OSROnlyBCI=62 47 while(x < 0) x += 1000000000; 48 sb.append('=').append(x).append('\n'); 49 } 50 if (sb.toString().hashCode() != 0xaba94591) { 51 throw new Exception("Unexpected result"); 52 } 53 } catch(OutOfMemoryError e) { 54 // small heap, ignore 55 } 56 } 57 } 58