1 /*
   2  * Copyright (c) 2013, 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 
  24 /*
  25  * @test
  26  * @bug 8027751
  27  * @requires vm.gc=="G1" | vm.gc=="null"
  28  * @summary C1 crashes generating G1 post-barrier in Unsafe.getAndSetObject() intrinsic because of the new value spill
  29  * @run main/othervm -XX:+UseG1GC C1ObjectSpillInLogicOp
  30  *
  31  * G1 barriers use logical operators (xor) on T_OBJECT mixed with T_LONG or T_INT.
  32  * The current implementation of logical operations on x86 in C1 doesn't allow for long operands to be on stack.
  33  * There is a special code in the register allocator that forces long arguments in registers on x86. However T_OBJECT
  34  * can be spilled just fine, and in that case the xor emission will fail.
  35  */
  36 
  37 import java.util.concurrent.atomic.*;
  38 
  39 public class C1ObjectSpillInLogicOp {
  40   public static void main(String[] args) {
  41     AtomicReferenceArray<Integer> x = new AtomicReferenceArray(128);
  42     Integer y = new Integer(0);
  43     for (int i = 0; i < 50000; i++) {
  44       x.getAndSet(i % x.length(), y);
  45     }
  46   }
  47 }