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 <list>
15#include <string>
16#include <vector>
17
18#include <benchmark/benchmark.h>
19#include "../../GenerateInput.h"
20
21int main(int argc, char** argv) {
22 auto std_adjacent_find = [](auto first, auto last) { return std::adjacent_find(first, last); };
23 auto std_adjacent_find_pred = [](auto first, auto last) {
24 return std::adjacent_find(first, last, [](auto x, auto y) {
25 benchmark::DoNotOptimize(x);
26 benchmark::DoNotOptimize(y);
27 return x == y;
28 });
29 };
30 auto ranges_adjacent_find_pred = [](auto first, auto last) {
31 return std::ranges::adjacent_find(first, last, [](auto x, auto y) {
32 benchmark::DoNotOptimize(x);
33 benchmark::DoNotOptimize(y);
34 return x == y;
35 });
36 };
37
38 // Benchmark {std,ranges}::adjacent_find on a sequence of the form xyxyxyxyxyxyxyxyxyxy,
39 // which means we never find adjacent equal elements (the worst case of the algorithm).
40 {
41 auto bm = []<class Container>(std::string name, auto adjacent_find) {
42 benchmark::RegisterBenchmark(
43 name,
44 [adjacent_find](auto& st) {
45 std::size_t const size = st.range(0);
46 using ValueType = typename Container::value_type;
47 ValueType x = Generate<ValueType>::random();
48 ValueType y = random_different_from({x});
49 Container c;
50 for (std::size_t i = 0; i != size; ++i) {
51 c.push_back(i % 2 == 0 ? x : y);
52 }
53
54 for ([[maybe_unused]] auto _ : st) {
55 benchmark::DoNotOptimize(c);
56 auto result = adjacent_find(c.begin(), c.end());
57 benchmark::DoNotOptimize(result);
58 }
59 })
60 ->Arg(8)
61 ->Arg(50) // non power-of-two
62 ->Arg(1024)
63 ->Arg(8192)
64 ->Arg(1 << 20);
65 };
66
67 // {std,ranges}::adjacent_find
68 bm.operator()<std::vector<int>>(name: "std::adjacent_find(vector<int>)", adjacent_find: std_adjacent_find);
69 bm.operator()<std::deque<int>>(name: "std::adjacent_find(deque<int>)", adjacent_find: std_adjacent_find);
70 bm.operator()<std::list<int>>(name: "std::adjacent_find(list<int>)", adjacent_find: std_adjacent_find);
71 bm.operator()<std::vector<int>>("rng::adjacent_find(vector<int>)", std::ranges::adjacent_find);
72 bm.operator()<std::deque<int>>("rng::adjacent_find(deque<int>)", std::ranges::adjacent_find);
73 bm.operator()<std::list<int>>("rng::adjacent_find(list<int>)", std::ranges::adjacent_find);
74
75 // {std,ranges}::adjacent_find(pred)
76 bm.operator()<std::vector<int>>(name: "std::adjacent_find(vector<int>, pred)", adjacent_find: std_adjacent_find_pred);
77 bm.operator()<std::deque<int>>(name: "std::adjacent_find(deque<int>, pred)", adjacent_find: std_adjacent_find_pred);
78 bm.operator()<std::list<int>>(name: "std::adjacent_find(list<int>, pred)", adjacent_find: std_adjacent_find_pred);
79 bm.operator()<std::vector<int>>(name: "rng::adjacent_find(vector<int>, pred)", adjacent_find: ranges_adjacent_find_pred);
80 bm.operator()<std::deque<int>>(name: "rng::adjacent_find(deque<int>, pred)", adjacent_find: ranges_adjacent_find_pred);
81 bm.operator()<std::list<int>>(name: "rng::adjacent_find(list<int>, pred)", adjacent_find: ranges_adjacent_find_pred);
82 }
83
84 benchmark::Initialize(&argc, argv);
85 benchmark::RunSpecifiedBenchmarks();
86 benchmark::Shutdown();
87 return 0;
88}
89

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