1 /*
 2  * Copyright (c) 2020, 2022, 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.java.lang.foreign;
24 
25 import java.lang.foreign.Arena;
26 import java.lang.foreign.MemorySegment;
27 
28 import org.openjdk.jmh.annotations.Benchmark;
29 import org.openjdk.jmh.annotations.BenchmarkMode;
30 import org.openjdk.jmh.annotations.Fork;
31 import org.openjdk.jmh.annotations.Measurement;
32 import org.openjdk.jmh.annotations.Mode;
33 import org.openjdk.jmh.annotations.OutputTimeUnit;
34 import org.openjdk.jmh.annotations.Setup;
35 import org.openjdk.jmh.annotations.State;
36 import org.openjdk.jmh.annotations.TearDown;
37 import org.openjdk.jmh.annotations.Warmup;
38 
39 import java.lang.invoke.MethodHandles;
40 import java.lang.invoke.VarHandle;
41 import java.util.concurrent.TimeUnit;
42 
43 import static java.lang.foreign.ValueLayout.JAVA_INT;
44 
45 @BenchmarkMode(Mode.AverageTime)
46 @Warmup(iterations = 5, time = 500, timeUnit = TimeUnit.MILLISECONDS)
47 @Measurement(iterations = 10, time = 500, timeUnit = TimeUnit.MILLISECONDS)
48 @State(org.openjdk.jmh.annotations.Scope.Thread)
49 @OutputTimeUnit(TimeUnit.NANOSECONDS)
50 @Fork(value = 3, jvmArgsAppend = "--enable-preview")
51 public class VarHandleExact {
52 
53     static final VarHandle exact;
54     static final VarHandle generic;
55 
56     static {
57         generic = MethodHandles.memorySegmentViewVarHandle(JAVA_INT);
58         exact = generic.withInvokeExactBehavior();
59     }
60 
61     Arena arena;
62     MemorySegment data;
63 
64     @Setup
65     public void setup() {
66         arena = Arena.ofConfined();
67         data = arena.allocate(JAVA_INT);
68     }
69 
70     @TearDown
71     public void tearDown() {
72         arena.close();
73     }
74 
75     @Benchmark
76     public void exact_exactInvocation() {
77         exact.set(data, (long) 0, 42);
78     }
79 
80     @Benchmark
81     public void generic_genericInvocation() {
82         generic.set(data, 0, 42);
83     }
84 
85     @Benchmark
86     public void generic_exactInvocation() {
87         generic.set(data, (long) 0, 42);
88     }
89 }