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 8078426

    28  * @summary split if finds predicates on several incoming paths when unswitched's loops are optimized out

    29  * @run main/othervm -XX:+IgnoreUnrecognizedVMOptions -XX:-UseOnStackReplacement -XX:-BackgroundCompilation -XX:-UseCompressedOops TestSplitIfUnswitchedLoopsEliminated

    30  *

    31  */

    32 

    33 

    34 public class TestSplitIfUnswitchedLoopsEliminated {

    35 

    36     static class A {

    37         int f;

    38     }

    39 

    40     static A aa = new A();

    41     static A aaa = new A();

    42 

    43     static int test_helper(int stop, boolean unswitch) {

    44         A a = null;

    45         for (int i = 3; i < 10; i++) {

    46             if (unswitch) {

    47                 a = null;

    48             } else {

    49                 a = aa;

    50                 int v = a.f;

    51             }

    52         }

    53         if (stop != 4) {

    54             a = aaa;

    55         }

    56         if (a != null) {

    57             return a.f;

    58         }

    59         return 0;

    60     }

    61 

    62     static int test(boolean unswitch) {

    63         int stop = 1;

    64         for (; stop < 3; stop *= 4) {

    65         }

    66         return test_helper(stop, unswitch);

    67     }

    68 

    69     public static void main(String[] args) {

    70         for (int i = 0; i < 20000; i++) {

    71             test_helper(10, i%2 == 0);

    72             test(i%2 == 0);

    73         }

    74     }

    75 }