1//===----------------------------------------------------------------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8
9// UNSUPPORTED: c++03, c++11, c++14, c++17
10
11#include <algorithm>
12#include <cstddef>
13#include <deque>
14#include <initializer_list>
15#include <list>
16#include <string>
17#include <vector>
18
19#include <benchmark/benchmark.h>
20#include "../../GenerateInput.h"
21
22int main(int argc, char** argv) {
23 auto std_find_first_of = [](auto first1, auto last1, auto first2, auto last2) {
24 return std::find_first_of(first1, last1, first2, last2);
25 };
26 auto std_find_first_of_pred = [](auto first1, auto last1, auto first2, auto last2) {
27 return std::find_first_of(first1, last1, first2, last2, [](auto x, auto y) {
28 benchmark::DoNotOptimize(x);
29 benchmark::DoNotOptimize(y);
30 return x == y;
31 });
32 };
33 auto ranges_find_first_of_pred = [](auto first1, auto last1, auto first2, auto last2) {
34 return std::ranges::find_first_of(first1, last1, first2, last2, [](auto x, auto y) {
35 benchmark::DoNotOptimize(x);
36 benchmark::DoNotOptimize(y);
37 return x == y;
38 });
39 };
40
41 // Benchmark {std,ranges}::find_first_of where we never find a match in the needle, and the needle is small.
42 // This is the worst case of the most common case (a small needle).
43 {
44 auto bm = []<class Container>(std::string name, auto find_first_of) {
45 benchmark::RegisterBenchmark(
46 name,
47 [find_first_of](auto& st) {
48 std::size_t const size = st.range(0);
49 using ValueType = typename Container::value_type;
50 ValueType x = Generate<ValueType>::random();
51 ValueType y = random_different_from({x});
52 Container haystack(size, x);
53 Container needle(10, y);
54
55 for ([[maybe_unused]] auto _ : st) {
56 benchmark::DoNotOptimize(haystack);
57 benchmark::DoNotOptimize(needle);
58 auto result = find_first_of(haystack.begin(), haystack.end(), needle.begin(), needle.end());
59 benchmark::DoNotOptimize(result);
60 }
61 })
62 ->Arg(32)
63 ->Arg(50) // non power-of-two
64 ->Arg(1024)
65 ->Arg(8192);
66 };
67 // {std,ranges}::find_first_of(it1, it1, it2, it2)
68 bm.operator()<std::vector<int>>(name: "std::find_first_of(vector<int>) (small needle)", find_first_of: std_find_first_of);
69 bm.operator()<std::deque<int>>(name: "std::find_first_of(deque<int>) (small needle)", find_first_of: std_find_first_of);
70 bm.operator()<std::list<int>>(name: "std::find_first_of(list<int>) (small needle)", find_first_of: std_find_first_of);
71 bm.operator()<std::vector<int>>("rng::find_first_of(vector<int>) (small needle)", std::ranges::find_first_of);
72 bm.operator()<std::deque<int>>("rng::find_first_of(deque<int>) (small needle)", std::ranges::find_first_of);
73 bm.operator()<std::list<int>>("rng::find_first_of(list<int>) (small needle)", std::ranges::find_first_of);
74
75 // {std,ranges}::find_first_of(it1, it1, it2, it2, pred)
76 bm.operator()<std::vector<int>>(name: "std::find_first_of(vector<int>, pred) (small needle)", find_first_of: std_find_first_of_pred);
77 bm.operator()<std::deque<int>>(name: "std::find_first_of(deque<int>, pred) (small needle)", find_first_of: std_find_first_of_pred);
78 bm.operator()<std::list<int>>(name: "std::find_first_of(list<int>, pred) (small needle)", find_first_of: std_find_first_of_pred);
79 bm.operator()<std::vector<int>>(name: "rng::find_first_of(vector<int>, pred) (small needle)", find_first_of: ranges_find_first_of_pred);
80 bm.operator()<std::deque<int>>(name: "rng::find_first_of(deque<int>, pred) (small needle)", find_first_of: ranges_find_first_of_pred);
81 bm.operator()<std::list<int>>(name: "rng::find_first_of(list<int>, pred) (small needle)", find_first_of: ranges_find_first_of_pred);
82 }
83
84 // Special case: the needle is large compared to the haystack, and we find a match early in the haystack.
85 {
86 auto bm = []<class Container>(std::string name, auto find_first_of) {
87 benchmark::RegisterBenchmark(
88 name,
89 [find_first_of](auto& st) {
90 std::size_t const size = st.range(0);
91 using ValueType = typename Container::value_type;
92 ValueType x = Generate<ValueType>::random();
93 ValueType y = random_different_from({x});
94 Container haystack(size, x);
95 Container needle(size * 10, y);
96
97 // put a match at 10% of the haystack
98 *std::next(haystack.begin(), haystack.size() / 10) = y;
99
100 for ([[maybe_unused]] auto _ : st) {
101 benchmark::DoNotOptimize(haystack);
102 benchmark::DoNotOptimize(needle);
103 auto result = find_first_of(haystack.begin(), haystack.end(), needle.begin(), needle.end());
104 benchmark::DoNotOptimize(result);
105 }
106 })
107 ->Arg(32)
108 ->Arg(50) // non power-of-two
109 ->Arg(1024)
110 ->Arg(8192);
111 };
112 // {std,ranges}::find_first_of(it1, it1, it2, it2)
113 bm.operator()<std::vector<int>>(name: "std::find_first_of(vector<int>) (large needle)", find_first_of: std_find_first_of);
114 bm.operator()<std::deque<int>>(name: "std::find_first_of(deque<int>) (large needle)", find_first_of: std_find_first_of);
115 bm.operator()<std::list<int>>(name: "std::find_first_of(list<int>) (large needle)", find_first_of: std_find_first_of);
116 bm.operator()<std::vector<int>>("rng::find_first_of(vector<int>) (large needle)", std::ranges::find_first_of);
117 bm.operator()<std::deque<int>>("rng::find_first_of(deque<int>) (large needle)", std::ranges::find_first_of);
118 bm.operator()<std::list<int>>("rng::find_first_of(list<int>) (large needle)", std::ranges::find_first_of);
119
120 // {std,ranges}::find_first_of(it1, it1, it2, it2, pred)
121 bm.operator()<std::vector<int>>(name: "std::find_first_of(vector<int>, pred) (large needle)", find_first_of: std_find_first_of_pred);
122 bm.operator()<std::deque<int>>(name: "std::find_first_of(deque<int>, pred) (large needle)", find_first_of: std_find_first_of_pred);
123 bm.operator()<std::list<int>>(name: "std::find_first_of(list<int>, pred) (large needle)", find_first_of: std_find_first_of_pred);
124 bm.operator()<std::vector<int>>(name: "rng::find_first_of(vector<int>, pred) (large needle)", find_first_of: ranges_find_first_of_pred);
125 bm.operator()<std::deque<int>>(name: "rng::find_first_of(deque<int>, pred) (large needle)", find_first_of: ranges_find_first_of_pred);
126 bm.operator()<std::list<int>>(name: "rng::find_first_of(list<int>, pred) (large needle)", find_first_of: ranges_find_first_of_pred);
127 }
128
129 benchmark::Initialize(&argc, argv);
130 benchmark::RunSpecifiedBenchmarks();
131 benchmark::Shutdown();
132 return 0;
133}
134

source code of libcxx/test/benchmarks/algorithms/nonmodifying/find_first_of.bench.cpp