--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/hotspot/test/compiler/7190310/Test7190310_unsafe.java	Mon Aug 20 09:58:58 2012 -0700
@@ -0,0 +1,142 @@
+/*
+ * Copyright (c) 2012, Oracle and/or its affiliates. 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 7190310
+ * @summary Inlining WeakReference.get(), and hoisting $referent may lead to non-terminating loops
+ * @run main/othervm -Xbatch Test7190310_unsafe
+ */
+
+import java.lang.ref.*;
+import java.lang.reflect.*;
+import sun.misc.Unsafe;
+
+public class Test7190310_unsafe {
+
+  static class TestObject {
+    public String toString() {
+      return "TestObject";
+    }
+  };
+
+  private static TestObject str = new TestObject();
+  private static final WeakReference ref = new WeakReference(str);
+
+  private TestObject obj;
+
+  public static void main(String[] args) throws Exception {
+    Class c = Test7190310_unsafe.class.getClassLoader().loadClass("sun.misc.Unsafe");
+    Field f = c.getDeclaredField("theUnsafe");
+    f.setAccessible(true);
+    Unsafe unsafe = (Unsafe)f.get(c);
+
+    f = Reference.class.getDeclaredField("referent");
+    f.setAccessible(true);
+    long referent_offset = unsafe.objectFieldOffset(f);
+
+    Test7190310_unsafe t = new Test7190310_unsafe();
+    TestObject o = new TestObject();
+    t.obj = o;
+
+    // Warmup (compile methods)
+    System.err.println("Warmup");
+    Object obj = null;
+    for (int i = 0; i < 11000; i++) {
+      obj = getRef0(ref);
+    }
+    for (int i = 0; i < 11000; i++) {
+      obj = getRef1(unsafe, ref, referent_offset);
+    }
+    for (int i = 0; i < 11000; i++) {
+      obj = getRef2(unsafe, ref, referent_offset);
+    }
+    for (int i = 0; i < 11000; i++) {
+      obj = getRef3(unsafe, ref, referent_offset);
+    }
+    for (int i = 0; i < 11000; i++) {
+      obj = getRef4(unsafe, t, referent_offset);
+    }
+
+    // Access verification
+    System.err.println("Verification");
+    if (!verifyGet(referent_offset, unsafe)) {
+      System.exit(97);
+    }
+
+    obj = getRef3(unsafe, t, referent_offset);
+    if (obj != o) {
+      System.out.println("FAILED: unsafe.getObject(Object, " + referent_offset + ") " + obj + " != " + o);
+      System.exit(97);
+    }
+    obj = getRef4(unsafe, t, referent_offset);
+    if (obj != o) {
+      System.out.println("FAILED: unsafe.getObject(Test7190310, " + referent_offset + ") " + obj + " != " + o);
+      System.exit(97);
+    }
+  }
+
+  static boolean verifyGet(long referent_offset, Unsafe unsafe) throws Exception {
+    // Access verification
+    System.out.println("referent: " + str);
+    Object obj = getRef0(ref);
+    if (obj != str) {
+      System.out.println("FAILED: weakRef.get() " + obj + " != " + str);
+      return false;
+    }
+    obj = getRef1(unsafe, ref, referent_offset);
+    if (obj != str) {
+      System.out.println("FAILED: unsafe.getObject(weakRef, " + referent_offset + ") " + obj + " != " + str);
+      return false;
+    }
+    obj = getRef2(unsafe, ref, referent_offset);
+    if (obj != str) {
+      System.out.println("FAILED: unsafe.getObject(abstRef, " + referent_offset + ") " + obj + " != " + str);
+      return false;
+    }
+    obj = getRef3(unsafe, ref, referent_offset);
+    if (obj != str) {
+      System.out.println("FAILED: unsafe.getObject(Object, " + referent_offset + ") " + obj + " != " + str);
+      return false;
+    }
+    return true;
+  }
+
+  static Object getRef0(WeakReference ref) throws Exception {
+    return ref.get();
+  }
+  static Object getRef1(Unsafe unsafe, WeakReference ref, long referent_offset) throws Exception {
+    return unsafe.getObject(ref, referent_offset);
+  }
+  static Object getRef2(Unsafe unsafe, Reference ref, long referent_offset) throws Exception {
+    return unsafe.getObject(ref, referent_offset);
+  }
+  static Object getRef3(Unsafe unsafe, Object ref, long referent_offset) throws Exception {
+    return unsafe.getObject(ref, referent_offset);
+  }
+  static Object getRef4(Unsafe unsafe, Test7190310_unsafe ref, long referent_offset) throws Exception {
+    return unsafe.getObject(ref, referent_offset);
+  }
+}
+