| /* |
| * Copyright (c) 2016, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| /* |
| * @test |
| * @bug 8159016 |
| * @summary Tests correct dominator information after over-unrolling a loop. |
| * @requires vm.gc == "Parallel" | vm.gc == "null" |
| * |
| * @run main/othervm -XX:+IgnoreUnrecognizedVMOptions -Xcomp -XX:-TieredCompilation |
| * -XX:-UseG1GC -XX:+UseParallelGC |
| * compiler.loopopts.TestOverunrolling |
| */ |
| |
| package compiler.loopopts; |
| |
| public class TestOverunrolling { |
| |
| public static Object test(int arg) { |
| Object arr[] = new Object[3]; |
| int lim = (arg & 3); |
| // The pre loop is executed for one iteration, initializing p[0]. |
| // The main loop is unrolled twice, initializing p[1], p[2], p[3] and p[4]. |
| // The p[3] and p[4] stores are always out of bounds and removed. However, |
| // C2 is unable to remove the "over-unrolled", dead main loop. As a result, |
| // there is a control path from the main loop to the post loop without a |
| // memory path (because the last store was replaced by TOP). We crash |
| // because we use a memory edge from a non-dominating region. |
| for (int i = 0; i < lim; ++i) { |
| arr[i] = new Object(); |
| } |
| // Avoid EA |
| return arr; |
| } |
| |
| public static void main(String args[]) { |
| for (int i = 0; i < 42; ++i) { |
| test(i); |
| } |
| } |
| } |
| |