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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 <list>
#include <string>
#include <vector>
#include <benchmark/benchmark.h>
#include "../../GenerateInput.h"
int main(int argc, char** argv) {
auto std_adjacent_find = [](auto first, auto last) { return std::adjacent_find(first, last); };
auto std_adjacent_find_pred = [](auto first, auto last) {
return std::adjacent_find(first, last, [](auto x, auto y) {
benchmark::DoNotOptimize(x);
benchmark::DoNotOptimize(y);
return x == y;
});
};
auto ranges_adjacent_find_pred = [](auto first, auto last) {
return std::ranges::adjacent_find(first, last, [](auto x, auto y) {
benchmark::DoNotOptimize(x);
benchmark::DoNotOptimize(y);
return x == y;
});
};
// Benchmark {std,ranges}::adjacent_find on a sequence of the form xyxyxyxyxyxyxyxyxyxy,
// which means we never find adjacent equal elements (the worst case of the algorithm).
{
auto bm = []<class Container>(std::string name, auto adjacent_find) {
benchmark::RegisterBenchmark(
name,
[adjacent_find](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 c;
for (std::size_t i = 0; i != size; ++i) {
c.push_back(i % 2 == 0 ? x : y);
}
for ([[maybe_unused]] auto _ : st) {
benchmark::DoNotOptimize(c);
auto result = adjacent_find(c.begin(), c.end());
benchmark::DoNotOptimize(result);
}
})
->Arg(8)
->Arg(50) // non power-of-two
->Arg(1024)
->Arg(8192)
->Arg(1 << 20);
};
// {std,ranges}::adjacent_find
bm.operator()<std::vector<int>>("std::adjacent_find(vector<int>)", std_adjacent_find);
bm.operator()<std::deque<int>>("std::adjacent_find(deque<int>)", std_adjacent_find);
bm.operator()<std::list<int>>("std::adjacent_find(list<int>)", std_adjacent_find);
bm.operator()<std::vector<int>>("rng::adjacent_find(vector<int>)", std::ranges::adjacent_find);
bm.operator()<std::deque<int>>("rng::adjacent_find(deque<int>)", std::ranges::adjacent_find);
bm.operator()<std::list<int>>("rng::adjacent_find(list<int>)", std::ranges::adjacent_find);
// {std,ranges}::adjacent_find(pred)
bm.operator()<std::vector<int>>("std::adjacent_find(vector<int>, pred)", std_adjacent_find_pred);
bm.operator()<std::deque<int>>("std::adjacent_find(deque<int>, pred)", std_adjacent_find_pred);
bm.operator()<std::list<int>>("std::adjacent_find(list<int>, pred)", std_adjacent_find_pred);
bm.operator()<std::vector<int>>("rng::adjacent_find(vector<int>, pred)", ranges_adjacent_find_pred);
bm.operator()<std::deque<int>>("rng::adjacent_find(deque<int>, pred)", ranges_adjacent_find_pred);
bm.operator()<std::list<int>>("rng::adjacent_find(list<int>, pred)", ranges_adjacent_find_pred);
}
benchmark::Initialize(&argc, argv);
benchmark::RunSpecifiedBenchmarks();
benchmark::Shutdown();
return 0;
}
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