1 /*
2 * Copyright (c) 2016, 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 * @test
26 * @bug 8155781
27 * @modules java.base/jdk.internal.misc
28 *
29 * @run main/bootclasspath/othervm -XX:+IgnoreUnrecognizedVMOptions -XX:+UnlockDiagnosticVMOptions
30 * -XX:-TieredCompilation -Xbatch
31 * -XX:+UseCompressedOops -XX:+UseCompressedClassPointers
32 * -XX:CompileCommand=dontinline,compiler.unsafe.OpaqueAccesses::test*
33 * compiler.unsafe.OpaqueAccesses
34 * @run main/bootclasspath/othervm -XX:+IgnoreUnrecognizedVMOptions -XX:+UnlockDiagnosticVMOptions
35 * -XX:-TieredCompilation -Xbatch
36 * -XX:-UseCompressedOops -XX:+UseCompressedClassPointers
37 * -XX:CompileCommand=dontinline,compiler.unsafe.OpaqueAccesses::test*
38 * compiler.unsafe.OpaqueAccesses
39 */
40 package compiler.unsafe;
41
42 import jdk.internal.misc.Unsafe;
43
44 import java.lang.reflect.Field;
45
46 public class OpaqueAccesses {
47 private static final Unsafe UNSAFE = Unsafe.getUnsafe();
48
49 private static final Object INSTANCE = new OpaqueAccesses();
50
51 private static final Object[] ARRAY = new Object[10];
52
53 private static final long F_OFFSET;
54 private static final long E_OFFSET;
55
56 static {
57 try {
58 Field field = OpaqueAccesses.class.getDeclaredField("f");
59 F_OFFSET = UNSAFE.objectFieldOffset(field);
60
61 E_OFFSET = UNSAFE.arrayBaseOffset(ARRAY.getClass());
62 } catch (NoSuchFieldException e) {
63 throw new Error(e);
64 }
65 }
66
67 private Object f = new Object();
68 private long l1, l2;
69
70 static Object testFixedOffsetField(Object o) {
71 return UNSAFE.getReference(o, F_OFFSET);
72 }
73
74 static int testFixedOffsetHeader0(Object o) {
75 return UNSAFE.getInt(o, 0);
76 }
77
78 static int testFixedOffsetHeader4(Object o) {
79 return UNSAFE.getInt(o, 4);
80 }
81
82 static int testFixedOffsetHeader8(Object o) {
83 return UNSAFE.getInt(o, 8);
84 }
85
86 static int testFixedOffsetHeader12(Object o) {
87 return UNSAFE.getInt(o, 12);
88 }
89
90 static int testFixedOffsetHeader16(Object o) {
91 return UNSAFE.getInt(o, 16);
92 }
93
94 static int testFixedOffsetHeader17(Object o) {
95 return UNSAFE.getIntUnaligned(o, 17);
96 }
97
98 static Object testFixedBase(long off) {
99 return UNSAFE.getReference(INSTANCE, off);
100 }
101
102 static Object testOpaque(Object o, long off) {
103 return UNSAFE.getReference(o, off);
104 }
105
106 static int testFixedOffsetHeaderArray0(Object[] arr) {
107 return UNSAFE.getInt(arr, 0);
108 }
109
110 static int testFixedOffsetHeaderArray4(Object[] arr) {
111 return UNSAFE.getInt(arr, 4);
112 }
113
114 static int testFixedOffsetHeaderArray8(Object[] arr) {
115 return UNSAFE.getInt(arr, 8);
116 }
117
118 static int testFixedOffsetHeaderArray12(Object[] arr) {
119 return UNSAFE.getInt(arr, 12);
120 }
121
122 static int testFixedOffsetHeaderArray16(Object[] arr) {
123 return UNSAFE.getInt(arr, 16);
124 }
125
126 static int testFixedOffsetHeaderArray17(Object[] arr) {
127 return UNSAFE.getIntUnaligned(arr, 17);
128 }
129
130 static Object testFixedOffsetArray(Object[] arr) {
131 return UNSAFE.getReference(arr, E_OFFSET);
132 }
133
134 static Object testFixedBaseArray(long off) {
135 return UNSAFE.getReference(ARRAY, off);
136 }
137
138 static Object testOpaqueArray(Object[] o, long off) {
139 return UNSAFE.getReference(o, off);
140 }
141
142 static final long ADDR = UNSAFE.allocateMemory(10);
143 static boolean flag;
144
145 static int testMixedAccess() {
146 flag = !flag;
147 Object o = (flag ? INSTANCE : null);
148 long off = (flag ? F_OFFSET : ADDR);
149 return UNSAFE.getInt(o, off);
150 }
151
152 public static void main(String[] args) {
153 for (int i = 0; i < 20_000; i++) {
154 // Instance
155 testFixedOffsetField(INSTANCE);
156 testFixedOffsetHeader0(INSTANCE);
157 testFixedOffsetHeader4(INSTANCE);
158 testFixedOffsetHeader8(INSTANCE);
159 testFixedOffsetHeader12(INSTANCE);
160 testFixedOffsetHeader16(INSTANCE);
161 testFixedOffsetHeader17(INSTANCE);
162 testFixedBase(F_OFFSET);
163 testOpaque(INSTANCE, F_OFFSET);
164 testMixedAccess();
165
166 // Array
167 testFixedOffsetHeaderArray0(ARRAY);
168 testFixedOffsetHeaderArray4(ARRAY);
169 testFixedOffsetHeaderArray8(ARRAY);
170 testFixedOffsetHeaderArray12(ARRAY);
171 testFixedOffsetHeaderArray16(ARRAY);
172 testFixedOffsetHeaderArray17(ARRAY);
173 testFixedOffsetArray(ARRAY);
174 testFixedBaseArray(E_OFFSET);
175 testOpaqueArray(ARRAY, E_OFFSET);
176 }
177 System.out.println("TEST PASSED");
178 }
179 }