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//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
// UNSUPPORTED: c++03, c++11, c++14, c++17
#include <algorithm>
#include <cstddef>
#include <deque>
#include <initializer_list>
#include <list>
#include <string>
#include <vector>
#include <benchmark/benchmark.h>
#include "../../GenerateInput.h"
int main(int argc, char** argv) {
auto std_find_first_of = [](auto first1, auto last1, auto first2, auto last2) {
return std::find_first_of(first1, last1, first2, last2);
};
auto std_find_first_of_pred = [](auto first1, auto last1, auto first2, auto last2) {
return std::find_first_of(first1, last1, first2, last2, [](auto x, auto y) {
benchmark::DoNotOptimize(x);
benchmark::DoNotOptimize(y);
return x == y;
});
};
auto ranges_find_first_of_pred = [](auto first1, auto last1, auto first2, auto last2) {
return std::ranges::find_first_of(first1, last1, first2, last2, [](auto x, auto y) {
benchmark::DoNotOptimize(x);
benchmark::DoNotOptimize(y);
return x == y;
});
};
// Benchmark {std,ranges}::find_first_of where we never find a match in the needle, and the needle is small.
// This is the worst case of the most common case (a small needle).
{
auto bm = []<class Container>(std::string name, auto find_first_of) {
benchmark::RegisterBenchmark(
name,
[find_first_of](auto& st) {
std::size_t const size = st.range(0);
using ValueType = typename Container::value_type;
ValueType x = Generate<ValueType>::random();
ValueType y = random_different_from({x});
Container haystack(size, x);
Container needle(10, y);
for ([[maybe_unused]] auto _ : st) {
benchmark::DoNotOptimize(haystack);
benchmark::DoNotOptimize(needle);
auto result = find_first_of(haystack.begin(), haystack.end(), needle.begin(), needle.end());
benchmark::DoNotOptimize(result);
}
})
->Arg(32)
->Arg(50) // non power-of-two
->Arg(1024)
->Arg(8192);
};
// {std,ranges}::find_first_of(it1, it1, it2, it2)
bm.operator()<std::vector<int>>("std::find_first_of(vector<int>) (small needle)", std_find_first_of);
bm.operator()<std::deque<int>>("std::find_first_of(deque<int>) (small needle)", std_find_first_of);
bm.operator()<std::list<int>>("std::find_first_of(list<int>) (small needle)", std_find_first_of);
bm.operator()<std::vector<int>>("rng::find_first_of(vector<int>) (small needle)", std::ranges::find_first_of);
bm.operator()<std::deque<int>>("rng::find_first_of(deque<int>) (small needle)", std::ranges::find_first_of);
bm.operator()<std::list<int>>("rng::find_first_of(list<int>) (small needle)", std::ranges::find_first_of);
// {std,ranges}::find_first_of(it1, it1, it2, it2, pred)
bm.operator()<std::vector<int>>("std::find_first_of(vector<int>, pred) (small needle)", std_find_first_of_pred);
bm.operator()<std::deque<int>>("std::find_first_of(deque<int>, pred) (small needle)", std_find_first_of_pred);
bm.operator()<std::list<int>>("std::find_first_of(list<int>, pred) (small needle)", std_find_first_of_pred);
bm.operator()<std::vector<int>>("rng::find_first_of(vector<int>, pred) (small needle)", ranges_find_first_of_pred);
bm.operator()<std::deque<int>>("rng::find_first_of(deque<int>, pred) (small needle)", ranges_find_first_of_pred);
bm.operator()<std::list<int>>("rng::find_first_of(list<int>, pred) (small needle)", ranges_find_first_of_pred);
}
// Special case: the needle is large compared to the haystack, and we find a match early in the haystack.
{
auto bm = []<class Container>(std::string name, auto find_first_of) {
benchmark::RegisterBenchmark(
name,
[find_first_of](auto& st) {
std::size_t const size = st.range(0);
using ValueType = typename Container::value_type;
ValueType x = Generate<ValueType>::random();
ValueType y = random_different_from({x});
Container haystack(size, x);
Container needle(size * 10, y);
// put a match at 10% of the haystack
*std::next(haystack.begin(), haystack.size() / 10) = y;
for ([[maybe_unused]] auto _ : st) {
benchmark::DoNotOptimize(haystack);
benchmark::DoNotOptimize(needle);
auto result = find_first_of(haystack.begin(), haystack.end(), needle.begin(), needle.end());
benchmark::DoNotOptimize(result);
}
})
->Arg(32)
->Arg(50) // non power-of-two
->Arg(1024)
->Arg(8192);
};
// {std,ranges}::find_first_of(it1, it1, it2, it2)
bm.operator()<std::vector<int>>("std::find_first_of(vector<int>) (large needle)", std_find_first_of);
bm.operator()<std::deque<int>>("std::find_first_of(deque<int>) (large needle)", std_find_first_of);
bm.operator()<std::list<int>>("std::find_first_of(list<int>) (large needle)", std_find_first_of);
bm.operator()<std::vector<int>>("rng::find_first_of(vector<int>) (large needle)", std::ranges::find_first_of);
bm.operator()<std::deque<int>>("rng::find_first_of(deque<int>) (large needle)", std::ranges::find_first_of);
bm.operator()<std::list<int>>("rng::find_first_of(list<int>) (large needle)", std::ranges::find_first_of);
// {std,ranges}::find_first_of(it1, it1, it2, it2, pred)
bm.operator()<std::vector<int>>("std::find_first_of(vector<int>, pred) (large needle)", std_find_first_of_pred);
bm.operator()<std::deque<int>>("std::find_first_of(deque<int>, pred) (large needle)", std_find_first_of_pred);
bm.operator()<std::list<int>>("std::find_first_of(list<int>, pred) (large needle)", std_find_first_of_pred);
bm.operator()<std::vector<int>>("rng::find_first_of(vector<int>, pred) (large needle)", ranges_find_first_of_pred);
bm.operator()<std::deque<int>>("rng::find_first_of(deque<int>, pred) (large needle)", ranges_find_first_of_pred);
bm.operator()<std::list<int>>("rng::find_first_of(list<int>, pred) (large needle)", ranges_find_first_of_pred);
}
benchmark::Initialize(&argc, argv);
benchmark::RunSpecifiedBenchmarks();
benchmark::Shutdown();
return 0;
}
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