1 /*

     2  * Copyright (c) 2019, 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

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    23 

    24 /**

    25  * @test

    26  * @bug 8233529

    27  * @summary Verify that correct loops are selected when trying to remove main/post.

    28  * @run main/othervm -XX:-TieredCompilation -Xbatch

    29  *                   -XX:CompileCommand=compileonly,compiler.loopopts.TestRemoveMainPostLoops::test

    30  *                   compiler.loopopts.TestRemoveMainPostLoops

    31  */

    32 

    33 package compiler.loopopts;

    34 

    35 public class TestRemoveMainPostLoops {

    36     static int cnt1 = 0;

    37     int cnt2 = 0;

    38 

    39     void testCallee() {

    40         // (5) Only main and post loops are created (no pre loop -> "PeelMainPost") and main is unrolled.

    41         for (int i = 0; i < 100; ++i) {

    42             // (4) Inner loop is fully unrolled and removed.

    43             for (int j = 0; j < 10; ++j) {

    44                 cnt1 += j;

    45             }

    46         }

    47     }

    48 

    49     void test() {

    50         for (int i = 0; i < 10_000; ++i) {

    51             // (0) testCallee method is inlined

    52             testCallee();

    53             cnt2 = 0;

    54             // (1) OSR compilation is triggered in this loop.

    55             // (2) Pre-/main-/post loops are created.

    56             // (3) Main and post loops found empty and removed.

    57             // (6) Pre loop is found empty, attempt to remove main and post loop then incorrectly selects main from (5).

    58             for (int j = 0; j < 10; ++j) {

    59                 cnt2 = cnt1 + j;

    60             }

    61         }

    62     }

    63 

    64     public static void main(String[] strArr) {

    65         TestRemoveMainPostLoops test = new TestRemoveMainPostLoops();

    66         for (int i = 0; i < 100; i++) {

    67             cnt1 = 0;

    68             test.cnt2 = 0;

    69             test.test();

    70             if (cnt1 != 45000000 || test.cnt2 != 45000009) {

    71                 throw new RuntimeException("Incorrect result: " + cnt1 + " " + test.cnt2);

    72             }

    73         }

    74     }

    75 }