/*

 * Copyright (c) 2018, Red Hat, Inc. All rights reserved.

 *

 * 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 java.util.concurrent.*;

/*

 * @test TestArrayCopyStress

 * @key gc

 * @requires vm.gc.Shenandoah

 *

 * @run main/othervm -XX:+UnlockExperimentalVMOptions -XX:+UseShenandoahGC -XX:TieredStopAtLevel=0 -Xmx16m TestArrayCopyStress

 */

public class TestArrayCopyStress {

    private static final int ARRAY_SIZE = 1000;

    private static final int ITERATIONS = 10000;

    static class Foo {

        int num;

        Foo(int num) {

            this.num = num;

        }

    }

    static class Bar {}

    public static void main(String[] args) throws Exception {

        for (int i = 0; i < ITERATIONS; i++) {

            testConjoint();

        }

    }

    private static void testConjoint() {

        Foo[] array = new Foo[ARRAY_SIZE];

        for (int i = 0; i < ARRAY_SIZE; i++) {

            array[i] = new Foo(i);

        }

        int src_idx = ThreadLocalRandom.current().nextInt(0, ARRAY_SIZE);

        int dst_idx = ThreadLocalRandom.current().nextInt(0, ARRAY_SIZE);

        int len = ThreadLocalRandom.current().nextInt(0, Math.min(ARRAY_SIZE - src_idx, ARRAY_SIZE - dst_idx));

        System.arraycopy(array, src_idx, array, dst_idx, len);

        for (int i = 0; i < ARRAY_SIZE; i++) {

            if (i >= dst_idx && i < dst_idx + len) {

                assertEquals(array[i].num, i - (dst_idx - src_idx));

            } else {

                assertEquals(array[i].num, i);

            }

        }

    }

    private static void assertEquals(int a, int b) {

        if (a != b) throw new RuntimeException("assert failed");

    }

}