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 21 * questions. 22 */ 23 24 import sun.hotspot.WhiteBox; 25 26 import java.lang.reflect.Method; 27 import java.util.HashMap; 28 29 public class TestJIT { 30 31 private static final WhiteBox WHITE_BOX = WhiteBox.getWhiteBox(); 32 33 static void doSomething() { 34 HashMap<String,String> map = new HashMap<>(); 35 for (int i=0; i<400; i++) { 36 // Call these methods so that the class/field/method references used 37 // by these methods are resolved. This allows C2 to compile more code. 38 String x = "Hello" + i; 39 map.put(x, x); 40 map.get(x); 41 } 42 } 43 44 static public void main(String[] args) throws NoSuchMethodException { 45 Method put_method = HashMap.class.getDeclaredMethod("put", Object.class, Object.class); 46 Method get_method = HashMap.class.getDeclaredMethod("get", Object.class); 47 Method test_method = TestJIT.class.getDeclaredMethod("doSomething"); 48 49 doSomething(); 50 51 // 4 == CompilerWhiteBoxTest.COMP_LEVEL_FULL_OPTIMIZATION => C2 52 WHITE_BOX.enqueueMethodForCompilation(get_method, 4); 53 WHITE_BOX.enqueueMethodForCompilation(put_method, 4); 54 WHITE_BOX.enqueueMethodForCompilation(test_method, 4); 55 56 // Try to start dynamic dumping while the above compilations are still in progesss 57 System.exit(0); 58 } 59 }