Mercurial > jdk8-mips64-public > hotspot / file revision

 /*

  * Copyright (c) 2013, 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.

  */

 import java.io.BufferedReader;

 import java.io.InputStreamReader;

 import java.lang.Class;

 import java.lang.String;

 import java.lang.System;

 import java.lang.management.ManagementFactory;

 import java.lang.management.RuntimeMXBean;

 import java.util.ArrayList;

 import java.util.List;

 import java.util.concurrent.CyclicBarrier;

 import java.util.regex.Matcher;

 import java.util.regex.Pattern;

 import java.lang.reflect.Field;

 import java.lang.reflect.Modifier;

 import sun.misc.Unsafe;

 import sun.misc.Contended;

 /*

  * @test

  * @bug     8014509

  * @summary \@Contended: explicit default value behaves differently from the implicit value

  *

  * @run main/othervm -XX:-RestrictContended DefaultValue

  */

 public class DefaultValue {

     private static final Unsafe U;

     private static int ADDRESS_SIZE;

     private static int HEADER_SIZE;

     static {

         // steal Unsafe

         try {

             Field unsafe = Unsafe.class.getDeclaredField("theUnsafe");

             unsafe.setAccessible(true);

             U = (Unsafe) unsafe.get(null);

         } catch (NoSuchFieldException | IllegalAccessException e) {

             throw new IllegalStateException(e);

         }

         // When running with CompressedOops on 64-bit platform, the address size

         // reported by Unsafe is still 8, while the real reference fields are 4 bytes long.

         // Try to guess the reference field size with this naive trick.

         try {

             long off1 = U.objectFieldOffset(CompressedOopsClass.class.getField("obj1"));

             long off2 = U.objectFieldOffset(CompressedOopsClass.class.getField("obj2"));

             ADDRESS_SIZE = (int) Math.abs(off2 - off1);

             HEADER_SIZE = (int) Math.min(off1, off2);

         } catch (NoSuchFieldException e) {

             ADDRESS_SIZE = -1;

         }

     }

     static class CompressedOopsClass {

         public Object obj1;

         public Object obj2;

     }

     public static boolean arePaddedPairwise(Class klass, String field1, String field2) throws Exception {

         Field f1 = klass.getField(field1);

         Field f2 = klass.getField(field2);

         int diff = offset(f1) - offset(f2);

         if (diff < 0) {

             // f1 is first

             return (offset(f2) - (offset(f1) + getSize(f1))) > 64;

         } else {

             // f2 is first

             return (offset(f1) - (offset(f2) + getSize(f2))) > 64;

         }

     }

     public static boolean sameLayout(Class klass1, Class klass2) throws Exception {

         for (Field f1 : klass1.getDeclaredFields()) {

             Field f2 = klass2.getDeclaredField(f1.getName());

             if (offset(f1) != offset(f2)) {

                 return false;

             }

         }

         for (Field f2 : klass1.getDeclaredFields()) {

             Field f1 = klass2.getDeclaredField(f2.getName());

             if (offset(f1) != offset(f2)) {

                 return false;

             }

         }

         return true;

     }

     public static boolean isStatic(Field field) {

         return Modifier.isStatic(field.getModifiers());

     }

     public static int offset(Field field) {

         if (isStatic(field)) {

             return (int) U.staticFieldOffset(field);

         } else {

             return (int) U.objectFieldOffset(field);

         }

     }

     public static int getSize(Field field) {

         Class type = field.getType();

         if (type == byte.class)    { return 1; }

         if (type == boolean.class) { return 1; }

         if (type == short.class)   { return 2; }

         if (type == char.class)    { return 2; }

         if (type == int.class)     { return 4; }

         if (type == float.class)   { return 4; }

         if (type == long.class)    { return 8; }

         if (type == double.class)  { return 8; }

         return ADDRESS_SIZE;

     }

     public static void main(String[] args) throws Exception {

         boolean endResult = true;

         if (!arePaddedPairwise(R1.class, "int1", "int2")) {

             System.err.println("R1 failed");

             endResult &= false;

         }

         if (!arePaddedPairwise(R2.class, "int1", "int2")) {

             System.err.println("R2 failed");

             endResult &= false;

         }

         if (!arePaddedPairwise(R3.class, "int1", "int2")) {

             System.err.println("R3 failed");

             endResult &= false;

         }

         System.out.println(endResult ? "Test PASSES" : "Test FAILS");

         if (!endResult) {

            throw new Error("Test failed");

         }

     }

     public static class R1 {

         @Contended

         public int int1;

         @Contended

         public int int2;

     }

     public static class R2 {

         @Contended("")

         public int int1;

         @Contended("")

         public int int2;

     }

     public static class R3 {

         @Contended()

         public int int1;

         @Contended()

         public int int2;

     }

 }