/* * Copyright (c) 2024, 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 8337660 * @summary Test that C2 does not remove blocks with BoxLock nodes that are * otherwise empty. * @run main/othervm -Xbatch -XX:LockingMode=1 * -XX:CompileOnly=compiler.locks.TestSynchronizeWithEmptyBlock::* * compiler.locks.TestSynchronizeWithEmptyBlock * @run main/othervm -Xbatch * -XX:CompileOnly=compiler.locks.TestSynchronizeWithEmptyBlock::* * compiler.locks.TestSynchronizeWithEmptyBlock */ package compiler.locks; public class TestSynchronizeWithEmptyBlock { static int c; static final Object obj = new Object(); static void test1() { synchronized (TestSynchronizeWithEmptyBlock.class) { int i = 0; while (i < 1000) { i++; if (i < 5); } } synchronized (TestSynchronizeWithEmptyBlock.class) { int i = 0; do { i++; if (i < 4) { boolean p = true; int j = 0; do { j++; if (p) { c++; } } while (j < 100); } } while (i < 1000); } } static void test2() { synchronized (obj) { for (long i = 0; i < 1_000_000_000_000L; i+=6_500_000_000L) {} } synchronized (obj) { for (long i = 0; i < 1_000_000_000_000L; i+=6_500_000_000L) {} } } public static void main(String[] args) { for (int i = 0; i < 10_000; i++) { test1(); } for (int i = 0; i < 10_000; i++) { test2(); } } }