1 /*

     2  * Copyright (c) 2014, 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  * @test

    26  * @bug 8032011

    27  * @summary biased locking's revoke_bias locks monitor in compiled frame with eliminated lock

    28  * @run main/othervm -XX:-UseOnStackReplacement -XX:CompileCommand=dontinline,TestLockEliminatedAtDeopt$A.m2 -XX:-BackgroundCompilation -XX:BiasedLockingStartupDelay=0 TestLockEliminatedAtDeopt

    29  *

    30  */

    31 

    32 public class TestLockEliminatedAtDeopt {

    33 

    34     static class A {

    35         void m() {

    36         }

    37 

    38         // This lock is not eliminated but biased to main thread on

    39         // first call

    40         synchronized void m2(boolean trap) {

    41             if (trap) {

    42                 new B();

    43             }

    44         }

    45     }

    46 

    47     static class B extends A {

    48         void m() {

    49         }

    50     }

    51 

    52     static void m1(boolean trap) {

    53         A a = new A();

    54         // This lock is eliminated by c2

    55         synchronized(a) {

    56             a.m2(trap);

    57             a.m();

    58         }

    59     }

    60 

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

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

    63             m1(false);

    64         }

    65         // Trigger uncommon trap in A.m2() (class unloaded) and

    66         // deoptimization of m1() (CHA invalidated). Uncommon trap

    67         // code locks monitor in m1's frame where's it's eliminated.

    68         m1(true);

    69     }

    70 }