1 /*
 2  * Copyright (c) 2025, 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 org.openjdk.bench.valhalla.hash;
24 
25 
26 import org.openjdk.jmh.annotations.Benchmark;
27 import org.openjdk.jmh.annotations.BenchmarkMode;
28 import org.openjdk.jmh.annotations.Fork;
29 import org.openjdk.jmh.annotations.Measurement;
30 import org.openjdk.jmh.annotations.Mode;
31 import org.openjdk.jmh.annotations.OutputTimeUnit;
32 import org.openjdk.jmh.annotations.Scope;
33 import org.openjdk.jmh.annotations.State;
34 import org.openjdk.jmh.annotations.Warmup;
35 
36 import java.util.concurrent.TimeUnit;
37 
38 @Fork(value = 3, jvmArgsAppend = {"--enable-preview"})
39 @Warmup(iterations = 5, time = 1)
40 @Measurement(iterations = 5, time = 1)
41 @OutputTimeUnit(TimeUnit.NANOSECONDS)
42 @BenchmarkMode(Mode.AverageTime)
43 @State(Scope.Thread)
44 public class Value1 {
45 
46     public static value class ValueInt1Hash {
47 
48         public final int v0;
49 
50         public ValueInt1Hash(int v0) {
51             this.v0 = v0;
52         }
53 
54         public int value() {
55             return v0;
56         }
57 
58         @Override
59         public int hashCode() {
60             return v0;
61         }
62 
63     }
64 
65     public static value class ValueInt1 {
66 
67         public final int v0;
68 
69         public ValueInt1(int v0) {
70             this.v0 = v0;
71         }
72 
73         public int value() {
74             return v0;
75         }
76 
77     }
78 
79 
80     @Benchmark
81     public int explicit() {
82         return new ValueInt1Hash(42).hashCode();
83     }
84 
85     @Benchmark
86     public int implicit() {
87         return new ValueInt1(42).hashCode();
88     }
89 
90     @Benchmark
91     public int direct() {
92         return System.identityHashCode(new ValueInt1(42));
93     }
94 }