forked from netty/netty
/
DecodeHexBenchmark.java
177 lines (162 loc) · 5.37 KB
/
DecodeHexBenchmark.java
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
/*
* Copyright 2019 The Netty Project
*
* The Netty Project licenses this file to you under the Apache License,
* version 2.0 (the "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at:
*
* https://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*/
package io.netty.handler.codec.http;
import io.netty.microbench.util.AbstractMicrobenchmark;
import io.netty.util.internal.PlatformDependent;
import io.netty.util.internal.StringUtil;
import org.jctools.util.Pow2;
import org.openjdk.jmh.annotations.Benchmark;
import org.openjdk.jmh.annotations.CompilerControl;
import org.openjdk.jmh.annotations.CompilerControl.Mode;
import org.openjdk.jmh.annotations.Measurement;
import org.openjdk.jmh.annotations.OutputTimeUnit;
import org.openjdk.jmh.annotations.Param;
import org.openjdk.jmh.annotations.Scope;
import org.openjdk.jmh.annotations.Setup;
import org.openjdk.jmh.annotations.State;
import org.openjdk.jmh.annotations.Warmup;
import java.util.Arrays;
import java.util.Random;
import java.util.concurrent.TimeUnit;
@State(Scope.Benchmark)
@Warmup(iterations = 5, time = 1)
@Measurement(iterations = 5, time = 1)
@OutputTimeUnit(TimeUnit.MICROSECONDS)
public class DecodeHexBenchmark extends AbstractMicrobenchmark {
@Param({
//with HEX chars
"135aBa9BBCEA030b947d79fCcaf48Bde",
//with HEX chars + 'g'
"4DDeA5gDD1C6fE567E1b6gf0C40FEcDg",
})
private String hex;
// Needs to specify a high number of inputs to allow the current strategy
// on nextHexDigits to produce enough branch-misses
@Param({ "2048" })
private int inputs;
private char[][] hexDigits;
private static final long SEED = 1578675524L;
private long next;
@Setup
public void init() {
final char[] hexCh = hex.toCharArray();
next = 0;
inputs = Pow2.roundToPowerOfTwo(inputs);
hexDigits = new char[inputs][];
hexDigits[0] = hexCh;
if (inputs > 1) {
final Random rnd = new Random(SEED);
for (int i = 1; i < inputs; i++) {
hexDigits[i] = shuffle(Arrays.copyOf(hexCh, hexCh.length), rnd);
}
}
}
// https://en.wikipedia.org/wiki/Fisher%E2%80%93Yates_shuffle
private static char[] shuffle(char[] chars, Random rnd) {
int index;
char tmp;
for (int i = chars.length - 1; i > 0; i--) {
index = rnd.nextInt(i + 1);
tmp = chars[index];
chars[index] = chars[i];
chars[i] = tmp;
}
return chars;
}
private int nextHexDigits() {
final int idx = (int) (next & (inputs - 1));
next++;
return idx;
}
@Benchmark
@CompilerControl(Mode.DONT_INLINE)
public long hexDigits() {
long v = 0;
final char[] hexDigits = this.hexDigits[nextHexDigits()];
for (int i = 0, size = hexDigits.length; i < size; i++) {
v += StringUtil.decodeHexNibble(hexDigits[i]);
}
return v;
}
@Benchmark
@CompilerControl(Mode.DONT_INLINE)
public long hexDigitsWithChecks() {
long v = 0;
final char[] hexDigits = this.hexDigits[nextHexDigits()];
for (int i = 0, size = hexDigits.length; i < size; i++) {
v += decodeHexNibbleWithCheck(hexDigits[i]);
}
return v;
}
@Benchmark
@CompilerControl(Mode.DONT_INLINE)
public long hexDigitsOriginal() {
long v = 0;
final char[] hexDigits = this.hexDigits[nextHexDigits()];
for (int i = 0, size = hexDigits.length; i < size; i++) {
v += decodeHexNibble(hexDigits[i]);
}
return v;
}
private static int decodeHexNibble(final char c) {
if (c >= '0' && c <= '9') {
return c - '0';
}
if (c >= 'A' && c <= 'F') {
return c - ('A' - 0xA);
}
if (c >= 'a' && c <= 'f') {
return c - ('a' - 0xA);
}
return -1;
}
private static final byte[] HEX2B;
static {
HEX2B = new byte['f' + 1];
Arrays.fill(HEX2B, (byte) -1);
HEX2B['0'] = (byte) 0;
HEX2B['1'] = (byte) 1;
HEX2B['2'] = (byte) 2;
HEX2B['3'] = (byte) 3;
HEX2B['4'] = (byte) 4;
HEX2B['5'] = (byte) 5;
HEX2B['6'] = (byte) 6;
HEX2B['7'] = (byte) 7;
HEX2B['8'] = (byte) 8;
HEX2B['9'] = (byte) 9;
HEX2B['A'] = (byte) 10;
HEX2B['B'] = (byte) 11;
HEX2B['C'] = (byte) 12;
HEX2B['D'] = (byte) 13;
HEX2B['E'] = (byte) 14;
HEX2B['F'] = (byte) 15;
HEX2B['a'] = (byte) 10;
HEX2B['b'] = (byte) 11;
HEX2B['c'] = (byte) 12;
HEX2B['d'] = (byte) 13;
HEX2B['e'] = (byte) 14;
HEX2B['f'] = (byte) 15;
}
private static int decodeHexNibbleWithCheck(final char c) {
if ((int) c >= HEX2B.length) {
return -1;
}
if (PlatformDependent.hasUnsafe()) {
return PlatformDependent.getByte(HEX2B, c);
}
return HEX2B[c];
}
}