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
17public class Main {
18  public static void main(String[] args) throws Exception {
19    System.loadLibrary(args[0]);
20    if (!hasJit()) {
21      return;
22    }
23    Foo.hotMethod();
24  }
25
26  public native static boolean hasJitCompiledEntrypoint(Class<?> cls, String methodName);
27  private native static boolean hasJit();
28}
29
30class Foo {
31  static void hotMethod() {
32    for (int i = 0; i < array.length; ++i) {
33      array[i] = array;
34    }
35  }
36
37  static {
38    array = new Object[10000];
39    while (!Main.hasJitCompiledEntrypoint(Foo.class, "hotMethod")) {
40      Foo.hotMethod();
41      try {
42        // Sleep to give a chance for the JIT to compile `hotMethod`.
43        Thread.sleep(100);
44      } catch (Exception e) {
45        // Ignore
46      }
47    }
48  }
49
50  static Object[] array;
51}
52