1 /*
   2  * Copyright (c) 2018, Red Hat, Inc. All rights reserved.
   3  *
   4  * This code is free software; you can redistribute it and/or modify it
   5  * under the terms of the GNU General Public License version 2 only, as
   6  * published by the Free Software Foundation.
   7  *
   8  * This code is distributed in the hope that it will be useful, but WITHOUT
   9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  11  * version 2 for more details (a copy is included in the LICENSE file that
  12  * accompanied this code).
  13  *
  14  * You should have received a copy of the GNU General Public License version
  15  * 2 along with this work; if not, write to the Free Software Foundation,
  16  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  17  *
  18  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  19  * or visit www.oracle.com if you need additional information or have any
  20  * questions.
  21  *
  22  */
  23 
  24 import java.util.concurrent.*;
  25 
  26 /*
  27  * @test TestArrayCopyStress
  28  *
  29  * @run main/othervm -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -XX:TieredStopAtLevel=0 -Xmx16m TestArrayCopyStress
  30  */
  31 public class TestArrayCopyStress {
  32 
  33   private static final int ARRAY_SIZE=1000;
  34   private static final int ITERATIONS = 10000;
  35 
  36   static class Foo {
  37       int num;
  38       Foo(int num) { this.num = num; }
  39   }
  40 
  41   static class Bar {}
  42 
  43   public static void main(String[] args) throws Exception {
  44     for (int i = 0; i < ITERATIONS; i++) {
  45       testConjoint();
  46     }
  47   }
  48 
  49   private static void testConjoint() {
  50     Foo[] array = new Foo[ARRAY_SIZE];
  51     for (int i = 0; i < ARRAY_SIZE; i++) {
  52       array[i] = new Foo(i);
  53     }
  54 
  55     int src_idx = ThreadLocalRandom.current().nextInt(0, ARRAY_SIZE);
  56     int dst_idx = ThreadLocalRandom.current().nextInt(0, ARRAY_SIZE);
  57     int len = ThreadLocalRandom.current().nextInt(0, Math.min(ARRAY_SIZE - src_idx, ARRAY_SIZE - dst_idx));
  58     System.arraycopy(array, src_idx, array, dst_idx, len);
  59 
  60     for (int i = 0; i < ARRAY_SIZE; i++) {
  61       if (i >= dst_idx && i < dst_idx + len) {
  62         assertEquals(array[i].num, i - (dst_idx - src_idx));
  63       } else {
  64         assertEquals(array[i].num, i);
  65       }
  66     }
  67   }
  68 
  69   private static void assertEquals(int a, int b) {
  70     if (a != b) throw new RuntimeException("assert failed");
  71   }
  72 
  73 }