1 /*
2 * Copyright (c) 2019, 2024, 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 package runtime.valhalla.inlinetypes;
24
25 import jdk.test.lib.Asserts;
26
27 import java.lang.reflect.Field;
28
29 import jdk.internal.value.ValueClass;
30 import jdk.internal.vm.annotation.ImplicitlyConstructible;
31 import jdk.internal.vm.annotation.LooselyConsistentValue;
32 import jdk.internal.vm.annotation.NullRestricted;
33
34
35 /*
36 * @test
37 * @summary Test support for empty inline types (no instance fields)
38 * @library /test/lib
39 * @modules java.base/jdk.internal.vm.annotation
40 * java.base/jdk.internal.value
41 * @enablePreview
42 * @compile EmptyInlineTest.java
43 * @run main/othervm -XX:InlineFieldMaxFlatSize=128 runtime.valhalla.inlinetypes.EmptyInlineTest
44 */
45
46 public class EmptyInlineTest {
47
48 @ImplicitlyConstructible
49 @LooselyConsistentValue
50 static value class EmptyInline {
51 public boolean isEmpty() {
52 return true;
53 }
54 }
55
56 @ImplicitlyConstructible
57 @LooselyConsistentValue
58 static value class EmptyField {
59 @NullRestricted
60 EmptyInline empty;
61
62 EmptyField() {
63 this.empty = new EmptyInline();
64 }
65 }
66
67 static class WithInt {
68 int i;
69 }
70
71 static class WithEmptyField extends WithInt {
72 // With current layout strategy for reference classs, the empty
73 // inline field would be placed between the int and the Object
74 // fields, along with some padding.
75 Object o;
76 @NullRestricted
77 EmptyInline empty;
78 }
79
80 public static void main(String[] args) {
81 // Create an empty inline
82 EmptyInline empty = new EmptyInline();
83 Asserts.assertTrue(empty.isEmpty());
84
85 // Create an inline with an empty inline field
86 EmptyField emptyField = new EmptyField();
87 Asserts.assertEquals(emptyField.empty.getClass(), EmptyInline.class);
88 Asserts.assertTrue(emptyField.empty.isEmpty());
89 System.out.println(emptyField.empty.isEmpty());
90
91 // Regular instance with an empty field inside
92 WithEmptyField w = new WithEmptyField();
93 Asserts.assertEquals(w.empty.getClass(), EmptyInline.class);
94 Asserts.assertTrue(w.empty.isEmpty());
95 w.empty = new EmptyInline();
96 Asserts.assertEquals(w.empty.getClass(), EmptyInline.class);
97 Asserts.assertTrue(w.empty.isEmpty());
98
99 // Create an array of empty inlines
100 EmptyInline[] emptyArray = (EmptyInline[])ValueClass.newNullRestrictedArray(EmptyInline.class, 100);
101 for(EmptyInline element : emptyArray) {
102 Asserts.assertEquals(element.getClass(), EmptyInline.class);
103 Asserts.assertTrue(element.isEmpty());
104 }
105
106 // Testing arrayCopy
107 EmptyInline[] array2 = (EmptyInline[])ValueClass.newNullRestrictedArray(EmptyInline.class, 100);
108 // with two arrays
109 System.arraycopy(emptyArray, 10, array2, 20, 50);
110 for(EmptyInline element : array2) {
111 Asserts.assertEquals(element.getClass(), EmptyInline.class);
112 Asserts.assertTrue(element.isEmpty());
113 }
114 // single array, no overlap
115 System.arraycopy(emptyArray, 10, emptyArray, 50, 20);
116 for(EmptyInline element : emptyArray) {
117 Asserts.assertEquals(element.getClass(), EmptyInline.class);
118 Asserts.assertTrue(element.isEmpty());
119 }
120 // single array with overlap
121 System.arraycopy(emptyArray, 10, emptyArray, 20, 50);
122 for(EmptyInline element : emptyArray) {
123 Asserts.assertEquals(element.getClass(), EmptyInline.class);
124 Asserts.assertTrue(element.isEmpty());
125 }
126
127 // Passing an empty inline in argument
128 assert isEmpty(empty);
129
130 // Returning an empty inline
131 assert getEmpty().isEmpty();
132
133 // Checking fields with reflection
134 Class<?> c = empty.getClass();
135 try {
136 Field[] fields = c.getDeclaredFields();
137 Asserts.assertTrue(fields.length == 0);
138 } catch (Throwable t) {
139 t.printStackTrace();
140 throw t;
141 }
142 WithEmptyField w0 = new WithEmptyField();
143 Class<?> c2 = w0.getClass();
144 try {
145 Field emptyfield = c2.getDeclaredField("empty");
146 EmptyInline e = (EmptyInline)emptyfield.get(w0);
147 Asserts.assertEquals(e.getClass(), EmptyInline.class);
148 Asserts.assertTrue(e.isEmpty());
149 emptyfield.set(w0, new EmptyInline());
150 e = (EmptyInline)emptyfield.get(w0);
151 Asserts.assertEquals(e.getClass(), EmptyInline.class);
152 Asserts.assertTrue(e.isEmpty());
153 } catch(Throwable t) {
154 t.printStackTrace();
155 throw new RuntimeException("Reflection tests failed: " + t);
156 }
157
158 // Testing JIT compiler
159 // for(int i=0; i < 100000; i++) {
160 // test();
161 // }
162 }
163
164 static boolean isEmpty(EmptyInline empty) {
165 return empty.isEmpty();
166 }
167
168 static EmptyInline getEmpty() {
169 return new EmptyInline();
170 }
171
172 static void test() {
173 for(int i=0; i < 10000; i++) {
174 Asserts.assertTrue(getEmpty().isEmpty());
175 }
176 }
177 }