1 /*
   2  * Copyright (c) 2008, 2012, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  */
  23 package org.graalvm.compiler.jtt.jdk;
  24 
  25 import org.graalvm.compiler.jtt.JTTTest;
  26 import org.junit.Test;
  27 
  28 import jdk.vm.ci.meta.ResolvedJavaMethod;
  29 
  30 public class Unsafe_compareAndSwap extends JTTTest {
  31 
  32     static final long valueOffset;
  33     static {
  34         try {
  35             valueOffset = UNSAFE.objectFieldOffset(Unsafe_compareAndSwap.class.getDeclaredField("value"));
  36         } catch (Exception ex) {
  37             throw new Error(ex);
  38         }
  39     }
  40 
  41     public static String test(Unsafe_compareAndSwap u, Object o, String expected, String newValue) {
  42         // First arg is not an array - can use a field write barrier
  43         UNSAFE.compareAndSwapObject(u, valueOffset, expected, newValue);
  44         // Not known if first arg is an array - different write barrier may be used
  45         UNSAFE.compareAndSwapObject(o, valueOffset, expected, newValue);
  46 
  47         return instance.value;
  48     }
  49 
  50     private String value;
  51 
  52     private static final Unsafe_compareAndSwap instance = new Unsafe_compareAndSwap();
  53 
  54     @Override
  55     protected void before(ResolvedJavaMethod m) {
  56         instance.value = "a";
  57     }
  58 
  59     @Test
  60     public void run0() throws Throwable {
  61         runTest("test", instance, instance, "a", "b");
  62     }
  63 }