/*

 * Copyright (c) 2016, Red Hat, Inc. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * 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.

 */

/**

 * @test

 * @bug 8167298

 * @summary Unsafe.compareAndExchangeObject should keep track of returned type after matching

 * @modules java.base/jdk.internal.misc

 * @run main/othervm -XX:+IgnoreUnrecognizedVMOptions -XX:-BackgroundCompilation -XX:-UseOnStackReplacement -XX:-UseCompressedOops TestCAEAntiDep

 *

 */

import java.lang.reflect.Field;

import jdk.internal.misc.Unsafe;

public class TestCAEAntiDep {

    static final jdk.internal.misc.Unsafe UNSAFE = Unsafe.getUnsafe();

    static final long O_OFFSET;

    static class C {

        int f1;

    }

    C o = new C();

    static {

        try {

            Field oField = TestCAEAntiDep.class.getDeclaredField("o");

            O_OFFSET = UNSAFE.objectFieldOffset(oField);

        } catch (Exception e) {

            throw new RuntimeException(e);

        }

    }

    static int m(TestCAEAntiDep test, Object expected, Object x) {

        C old = (C)UNSAFE.compareAndExchangeObjectVolatile(test, O_OFFSET, expected, x);

        int res = old.f1;

        old.f1 = 0x42;

        return res;

    }

    static public void main(String[] args) {

        TestCAEAntiDep test = new TestCAEAntiDep();

        for (int i = 0; i < 20000; i++) {

            m(test, test.o, test.o);

        }

    }

}