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 * 29 * @run main/othervm -XX:-UseOnStackReplacement 30 * -XX:CompileCommand=dontinline,compiler.uncommontrap.TestLockEliminatedAtDeopt$A::m2 31 * -XX:-BackgroundCompilation -XX:BiasedLockingStartupDelay=0 32 * compiler.uncommontrap.TestLockEliminatedAtDeopt 33 */ 34 35 package compiler.uncommontrap; 36 37 public class TestLockEliminatedAtDeopt { 38 39 static class A { 40 void m() { 41 } 42 43 // This lock is not eliminated but biased to main thread on 44 // first call 45 synchronized void m2(boolean trap) { 46 if (trap) { 47 new B(); 48 } 49 } 50 } 51 52 static class B extends A { 53 void m() { 54 } 55 } 56 57 static void m1(boolean trap) { 58 A a = new A(); 59 // This lock is eliminated by c2 60 synchronized(a) { 61 a.m2(trap); 62 a.m(); 63 } 64 } 65 66 public static void main(String[] args) { 67 for (int i = 0; i < 20000; i++) { 68 m1(false); 69 } 70 // Trigger uncommon trap in A.m2() (class unloaded) and 71 // deoptimization of m1() (CHA invalidated). Uncommon trap 72 // code locks monitor in m1's frame where's it's eliminated. 73 m1(true); 74 } 75 }