1 /*
  2  * Copyright (c) 2022, 2026, 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 id=with-coops
 26  * @library /test/lib /
 27  * @requires vm.bits == "64"
 28  * @modules java.base/jdk.internal.misc
 29  *          java.management
 30  * @build jdk.test.whitebox.WhiteBox
 31  * @run driver jdk.test.lib.helpers.ClassFileInstaller jdk.test.whitebox.WhiteBox
 32  * @run main/othervm -Xbootclasspath/a:. -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI -XX:+UseCompressedOops -XX:-UseCompactObjectHeaders BaseOffsets
 33  */
 34 
 35 /*
 36  * @test id=no-coops
 37  * @library /test/lib /
 38  * @requires vm.bits == "64"
 39  * @modules java.base/jdk.internal.misc
 40  *          java.management
 41  * @build jdk.test.whitebox.WhiteBox
 42  * @run driver jdk.test.lib.helpers.ClassFileInstaller jdk.test.whitebox.WhiteBox
 43  * @run main/othervm -Xbootclasspath/a:. -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI -XX:-UseCompressedOops -XX:-UseCompactObjectHeaders BaseOffsets
 44  */
 45 
 46 /*
 47  * @test id=with-coop-with-coh
 48  * @library /test/lib /
 49  * @requires vm.bits == "64"
 50  * @modules java.base/jdk.internal.misc
 51  *          java.management
 52  * @build jdk.test.whitebox.WhiteBox
 53  * @run driver jdk.test.lib.helpers.ClassFileInstaller jdk.test.whitebox.WhiteBox
 54  * @run main/othervm -Xbootclasspath/a:. -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI -XX:+UseCompressedOops -XX:+UseCompactObjectHeaders BaseOffsets
 55  */
 56 
 57 /*
 58  * @test id=no-coops-with-coh
 59  * @library /test/lib /
 60  * @requires vm.bits == "64"
 61  * @modules java.base/jdk.internal.misc
 62  *          java.management
 63  * @build jdk.test.whitebox.WhiteBox
 64  * @run driver jdk.test.lib.helpers.ClassFileInstaller jdk.test.whitebox.WhiteBox
 65  * @run main/othervm -Xbootclasspath/a:. -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI -XX:-UseCompressedOops -XX:+UseCompactObjectHeaders BaseOffsets
 66  */
 67 
 68 /*
 69  * @test id=32bit
 70  * @library /test/lib /
 71  * @requires vm.bits == "32"
 72  * @modules java.base/jdk.internal.misc
 73  *          java.management
 74  * @build jdk.test.whitebox.WhiteBox
 75  * @run driver jdk.test.lib.helpers.ClassFileInstaller jdk.test.whitebox.WhiteBox
 76  * @run main/othervm -Xbootclasspath/a:. -XX:+UnlockDiagnosticVMOptions -XX:+WhiteBoxAPI BaseOffsets
 77  */
 78 
 79 import java.lang.reflect.Field;
 80 import java.util.Arrays;
 81 import java.util.Comparator;
 82 import jdk.internal.misc.Unsafe;
 83 
 84 import jdk.test.lib.Asserts;
 85 import jdk.test.lib.Platform;
 86 import jdk.test.whitebox.WhiteBox;
 87 
 88 public class BaseOffsets {
 89 
 90     static class LIClass {
 91         public int i;
 92     }
 93 
 94     public static final WhiteBox WB = WhiteBox.getWhiteBox();
 95 
 96     static final long INT_OFFSET;
 97     static final long INT_ARRAY_OFFSET;
 98     static final long LONG_ARRAY_OFFSET;
 99     static {
100         if (!Platform.is64bit() || WB.getBooleanVMFlag("UseCompactObjectHeaders")) {
101             INT_OFFSET = 4;
102             INT_ARRAY_OFFSET = 8;
103             LONG_ARRAY_OFFSET = 8;
104         } else {
105             INT_OFFSET = 12;
106             INT_ARRAY_OFFSET = 16;
107             LONG_ARRAY_OFFSET = 16;
108         }
109     }
110 
111     static public void main(String[] args) {
112         Unsafe unsafe = Unsafe.getUnsafe();
113         Class c = LIClass.class;
114         Field[] fields = c.getFields();
115         for (int i = 0; i < fields.length; i++) {
116             long offset = unsafe.objectFieldOffset(fields[i]);
117             if (fields[i].getType() == int.class) {
118                 Asserts.assertEquals(offset, INT_OFFSET, "Misplaced int field");
119             } else {
120                 Asserts.fail("Unexpected field type");
121             }
122         }
123 
124         Asserts.assertEquals(unsafe.arrayBaseOffset(boolean[].class), INT_ARRAY_OFFSET,  "Misplaced boolean array base");
125         Asserts.assertEquals(unsafe.arrayBaseOffset(byte[].class),    INT_ARRAY_OFFSET,  "Misplaced byte    array base");
126         Asserts.assertEquals(unsafe.arrayBaseOffset(char[].class),    INT_ARRAY_OFFSET,  "Misplaced char    array base");
127         Asserts.assertEquals(unsafe.arrayBaseOffset(short[].class),   INT_ARRAY_OFFSET,  "Misplaced short   array base");
128         Asserts.assertEquals(unsafe.arrayBaseOffset(int[].class),     INT_ARRAY_OFFSET,  "Misplaced int     array base");
129         Asserts.assertEquals(unsafe.arrayBaseOffset(long[].class),    LONG_ARRAY_OFFSET, "Misplaced long    array base");
130         Asserts.assertEquals(unsafe.arrayBaseOffset(float[].class),   INT_ARRAY_OFFSET,  "Misplaced float   array base");
131         Asserts.assertEquals(unsafe.arrayBaseOffset(double[].class),  LONG_ARRAY_OFFSET, "Misplaced double  array base");
132         boolean narrowOops = System.getProperty("java.vm.compressedOopsMode") != null ||
133                              !Platform.is64bit();
134         long expected_objary_offset = narrowOops ? INT_ARRAY_OFFSET : LONG_ARRAY_OFFSET;
135         Asserts.assertEquals(unsafe.arrayBaseOffset(Object[].class),  expected_objary_offset, "Misplaced object  array base");
136     }
137 }