1 /*
2  * Copyright (C) 2012 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #include <stdint.h>
18 #include <string.h>
19 
20 #include <benchmark/benchmark.h>
21 
22 constexpr auto KB = 1024;
23 
24 #define AT_COMMON_SIZES \
25     Arg(8)->Arg(64)->Arg(512)->Arg(1*KB)->Arg(8*KB)->Arg(16*KB)->Arg(32*KB)->Arg(64*KB)
26 
27 // TODO: test unaligned operation too? (currently everything will be 8-byte aligned by malloc.)
28 
BM_string_memcmp(benchmark::State & state)29 static void BM_string_memcmp(benchmark::State& state) {
30   const size_t nbytes = state.range(0);
31   char* src = new char[nbytes]; char* dst = new char[nbytes];
32   memset(src, 'x', nbytes);
33   memset(dst, 'x', nbytes);
34 
35   volatile int c __attribute__((unused)) = 0;
36   while (state.KeepRunning()) {
37     c += memcmp(dst, src, nbytes);
38   }
39 
40   state.SetBytesProcessed(uint64_t(state.iterations()) * uint64_t(nbytes));
41   delete[] src;
42   delete[] dst;
43 }
44 BENCHMARK(BM_string_memcmp)->AT_COMMON_SIZES;
45 
BM_string_memcpy(benchmark::State & state)46 static void BM_string_memcpy(benchmark::State& state) {
47   const size_t nbytes = state.range(0);
48   char* src = new char[nbytes]; char* dst = new char[nbytes];
49   memset(src, 'x', nbytes);
50 
51   while (state.KeepRunning()) {
52     memcpy(dst, src, nbytes);
53   }
54 
55   state.SetBytesProcessed(uint64_t(state.iterations()) * uint64_t(nbytes));
56   delete[] src;
57   delete[] dst;
58 }
59 BENCHMARK(BM_string_memcpy)->AT_COMMON_SIZES;
60 
BM_string_memmove(benchmark::State & state)61 static void BM_string_memmove(benchmark::State& state) {
62   const size_t nbytes = state.range(0);
63   char* buf = new char[nbytes + 64];
64   memset(buf, 'x', nbytes + 64);
65 
66   while (state.KeepRunning()) {
67     memmove(buf, buf + 1, nbytes); // Worst-case overlap.
68   }
69 
70   state.SetBytesProcessed(uint64_t(state.iterations()) * uint64_t(nbytes));
71   delete[] buf;
72 }
73 BENCHMARK(BM_string_memmove)->AT_COMMON_SIZES;
74 
BM_string_memset(benchmark::State & state)75 static void BM_string_memset(benchmark::State& state) {
76   const size_t nbytes = state.range(0);
77   char* dst = new char[nbytes];
78 
79   while (state.KeepRunning()) {
80     memset(dst, 0, nbytes);
81   }
82 
83   state.SetBytesProcessed(uint64_t(state.iterations()) * uint64_t(nbytes));
84   delete[] dst;
85 }
86 BENCHMARK(BM_string_memset)->AT_COMMON_SIZES;
87 
BM_string_strlen(benchmark::State & state)88 static void BM_string_strlen(benchmark::State& state) {
89   const size_t nbytes = state.range(0);
90   char* s = new char[nbytes];
91   memset(s, 'x', nbytes);
92   s[nbytes - 1] = 0;
93 
94   volatile int c __attribute__((unused)) = 0;
95   while (state.KeepRunning()) {
96     c += strlen(s);
97   }
98 
99   state.SetBytesProcessed(uint64_t(state.iterations()) * uint64_t(nbytes));
100   delete[] s;
101 }
102 BENCHMARK(BM_string_strlen)->AT_COMMON_SIZES;
103