1 /*
   2  * Copyright (c) 2012, 2018, 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 package org.graalvm.compiler.graph;
  26 
  27 import java.lang.reflect.Field;
  28 
  29 import sun.misc.Unsafe;
  30 
  31 /**
  32  * Package private access to the {@link Unsafe} capability.
  33  */
  34 class UnsafeAccess {
  35 
  36     static final Unsafe UNSAFE = initUnsafe();
  37 
  38     private static Unsafe initUnsafe() {
  39         try {
  40             // Fast path when we are trusted.
  41             return Unsafe.getUnsafe();
  42         } catch (SecurityException se) {
  43             // Slow path when we are not trusted.
  44             try {
  45                 Field theUnsafe = Unsafe.class.getDeclaredField("theUnsafe");
  46                 theUnsafe.setAccessible(true);
  47                 return (Unsafe) theUnsafe.get(Unsafe.class);
  48             } catch (Exception e) {
  49                 throw new RuntimeException("exception while trying to get Unsafe", e);
  50             }
  51         }
  52     }
  53 }