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
|
// Copyright 2018 The Abseil Authors.
//
// Licensed 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.
#include "absl/strings/str_cat.h"
#include <cstdint>
#include <string>
#include "benchmark/benchmark.h"
#include "absl/strings/substitute.h"
namespace {
const char kStringOne[] = "Once Upon A Time, ";
const char kStringTwo[] = "There was a string benchmark";
// We want to include negative numbers in the benchmark, so this function
// is used to count 0, 1, -1, 2, -2, 3, -3, ...
inline int IncrementAlternatingSign(int i) {
return i > 0 ? -i : 1 - i;
}
void BM_Sum_By_StrCat(benchmark::State& state) {
int i = 0;
char foo[100];
for (auto _ : state) {
// NOLINTNEXTLINE(runtime/printf)
strcpy(foo, absl::StrCat(kStringOne, i, kStringTwo, i * 65536ULL).c_str());
int sum = 0;
for (char* f = &foo[0]; *f != 0; ++f) {
sum += *f;
}
benchmark::DoNotOptimize(sum);
i = IncrementAlternatingSign(i);
}
}
BENCHMARK(BM_Sum_By_StrCat);
void BM_StrCat_By_snprintf(benchmark::State& state) {
int i = 0;
char on_stack[1000];
for (auto _ : state) {
snprintf(on_stack, sizeof(on_stack), "%s %s:%d", kStringOne, kStringTwo, i);
i = IncrementAlternatingSign(i);
}
}
BENCHMARK(BM_StrCat_By_snprintf);
void BM_StrCat_By_Strings(benchmark::State& state) {
int i = 0;
for (auto _ : state) {
std::string result =
std::string(kStringOne) + " " + kStringTwo + ":" + absl::StrCat(i);
benchmark::DoNotOptimize(result);
i = IncrementAlternatingSign(i);
}
}
BENCHMARK(BM_StrCat_By_Strings);
void BM_StrCat_By_StringOpPlus(benchmark::State& state) {
int i = 0;
for (auto _ : state) {
std::string result = kStringOne;
result += " ";
result += kStringTwo;
result += ":";
result += absl::StrCat(i);
benchmark::DoNotOptimize(result);
i = IncrementAlternatingSign(i);
}
}
BENCHMARK(BM_StrCat_By_StringOpPlus);
void BM_StrCat_By_StrCat(benchmark::State& state) {
int i = 0;
for (auto _ : state) {
std::string result = absl::StrCat(kStringOne, " ", kStringTwo, ":", i);
benchmark::DoNotOptimize(result);
i = IncrementAlternatingSign(i);
}
}
BENCHMARK(BM_StrCat_By_StrCat);
void BM_HexCat_By_StrCat(benchmark::State& state) {
int i = 0;
for (auto _ : state) {
std::string result =
absl::StrCat(kStringOne, " ", absl::Hex(int64_t{i} + 0x10000000));
benchmark::DoNotOptimize(result);
i = IncrementAlternatingSign(i);
}
}
BENCHMARK(BM_HexCat_By_StrCat);
void BM_HexCat_By_Substitute(benchmark::State& state) {
int i = 0;
for (auto _ : state) {
std::string result = absl::Substitute(
"$0 $1", kStringOne, reinterpret_cast<void*>(int64_t{i} + 0x10000000));
benchmark::DoNotOptimize(result);
i = IncrementAlternatingSign(i);
}
}
BENCHMARK(BM_HexCat_By_Substitute);
void BM_FloatToString_By_StrCat(benchmark::State& state) {
int i = 0;
float foo = 0.0f;
for (auto _ : state) {
std::string result = absl::StrCat(foo += 1.001f, " != ", int64_t{i});
benchmark::DoNotOptimize(result);
i = IncrementAlternatingSign(i);
}
}
BENCHMARK(BM_FloatToString_By_StrCat);
void BM_DoubleToString_By_SixDigits(benchmark::State& state) {
int i = 0;
double foo = 0.0;
for (auto _ : state) {
std::string result =
absl::StrCat(absl::SixDigits(foo += 1.001), " != ", int64_t{i});
benchmark::DoNotOptimize(result);
i = IncrementAlternatingSign(i);
}
}
BENCHMARK(BM_DoubleToString_By_SixDigits);
} // namespace
|
