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

 *

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 * under the terms of the GNU General Public License version 2 only, as

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 *

 * 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.

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/*

 * @test

 * @bug 8143930

 * @summary C1 LinearScan asserts when compiling two back-to-back CompareAndSwapLongs

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

 * @run testng/othervm -Diters=200000 -XX:TieredStopAtLevel=1 UnsafeTwoCASLong

 */

import org.testng.annotations.Test;

import java.lang.reflect.Field;

import static org.testng.Assert.*;

public class UnsafeTwoCASLong {

    static final int ITERS = Integer.getInteger("iters", 1);

    static final jdk.internal.misc.Unsafe UNSAFE;

    static final long V_OFFSET;

    static {

        try {

            Field f = jdk.internal.misc.Unsafe.class.getDeclaredField("theUnsafe");

            f.setAccessible(true);

            UNSAFE = (jdk.internal.misc.Unsafe) f.get(null);

        } catch (Exception e) {

            throw new RuntimeException("Unable to get Unsafe instance.", e);

        }

        try {

            Field vField = UnsafeTwoCASLong.class.getDeclaredField("v");

            V_OFFSET = UNSAFE.objectFieldOffset(vField);

        } catch (Exception e) {

            throw new RuntimeException(e);

        }

    }

    long v;

    @Test

    public void testFieldInstance() {

        UnsafeTwoCASLong t = new UnsafeTwoCASLong();

        for (int c = 0; c < ITERS; c++) {

            testAccess(t, V_OFFSET);

        }

    }

    static void testAccess(Object base, long offset) {

        UNSAFE.compareAndSwapLong(base, offset, 1L, 2L);

        UNSAFE.compareAndSwapLong(base, offset, 2L, 1L);

    }

}