1 /* 2 * Copyright (C) 2017 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 public class Main { main(String[] args)18 public static void main(String[] args) throws Exception { 19 System.loadLibrary(args[0]); 20 if (!hasJit()) { 21 return; 22 } 23 // Force initialization. 24 Foo.initialize(); 25 } 26 hasJitCompiledEntrypoint(Class<?> cls, String methodName)27 public native static boolean hasJitCompiledEntrypoint(Class<?> cls, String methodName); hasJit()28 private native static boolean hasJit(); 29 } 30 31 class Foo { 32 // This method needs to be virtual for the test. Otherwise if it's a static method, 33 // the JIT compiler won't compile while its entrypoint is the resolution stub. $noinline$hotMethod()34 void $noinline$hotMethod() { 35 for (int i = 0; i < array.length; ++i) { 36 array[i] = array; 37 } 38 } 39 40 static { 41 array = new Object[10000]; 42 while (!Main.hasJitCompiledEntrypoint(Foo.class, "$noinline$hotMethod")) { 43 new Foo().$noinline$hotMethod(); 44 try { 45 // Sleep to give a chance for the JIT to compile `hotMethod`. 46 Thread.sleep(100); 47 } catch (Exception e) { 48 // Ignore 49 } 50 } 51 } 52 initialize()53 static void initialize() { 54 } 55 56 static Object[] array; 57 } 58