| /* |
| * Copyright (c) 2013, 2016, 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 jdk.internal.misc.Unsafe; |
| import jdk.internal.vm.annotation.Contended; |
| |
| /* |
| * @test |
| * @bug 8014509 |
| * @summary \@Contended: explicit default value behaves differently from the implicit value |
| * |
| * @modules java.base/jdk.internal.misc |
| * @modules java.base/jdk.internal.vm.annotation |
| * @run main/othervm -XX:-RestrictContended DefaultValue |
| */ |
| public class DefaultValue { |
| |
| private static final Unsafe U = Unsafe.getUnsafe(); |
| private static int ADDRESS_SIZE; |
| private static int HEADER_SIZE; |
| |
| static { |
| // 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; |
| } |
| |
| } |
| |