/* * Copyright (c) 2019, 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. */ import sun.hotspot.WhiteBox; import java.lang.reflect.Method; import java.util.HashMap; public class TestJIT { private static final WhiteBox WHITE_BOX = WhiteBox.getWhiteBox(); static void doSomething() { HashMap map = new HashMap<>(); for (int i=0; i<400; i++) { // Call these methods so that the class/field/method references used // by these methods are resolved. This allows C2 to compile more code. String x = "Hello" + i; map.put(x, x); map.get(x); } } static public void main(String[] args) throws NoSuchMethodException { Method put_method = HashMap.class.getDeclaredMethod("put", Object.class, Object.class); Method get_method = HashMap.class.getDeclaredMethod("get", Object.class); Method test_method = TestJIT.class.getDeclaredMethod("doSomething"); doSomething(); // 4 == CompilerWhiteBoxTest.COMP_LEVEL_FULL_OPTIMIZATION => C2 WHITE_BOX.enqueueMethodForCompilation(get_method, 4); WHITE_BOX.enqueueMethodForCompilation(put_method, 4); WHITE_BOX.enqueueMethodForCompilation(test_method, 4); // Try to start dynamic dumping while the above compilations are still in progesss System.exit(0); } }