libcxx/test/benchmarks/algorithms/modifying/swap_ranges.bench.cpp

//===----------------------------------------------------------------------===//
//
// 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 <iterator>
#include <list>
#include <string>
#include <vector>

#include "benchmark/benchmark.h"
#include "../../GenerateInput.h"

int main(int argc, char** argv) {
  auto std_swap_ranges = [](auto first1, auto last1, auto first2, auto) {
    return std::swap_ranges(first1, last1, first2);
  };

  // {std,ranges}::swap_ranges(normal container)
  {
    auto bm = []<class Container>(std::string name, auto swap_ranges) {
      benchmark::RegisterBenchmark(
          name,
          [swap_ranges](auto& st) {
            std::size_t const size = st.range(0);
            using ValueType        = typename Container::value_type;
            Container c1, c2;
            std::generate_n(std::back_inserter(c1), size, [] { return Generate<ValueType>::random(); });
            std::generate_n(std::back_inserter(c2), size, [] { return Generate<ValueType>::random(); });

            for ([[maybe_unused]] auto _ : st) {
              benchmark::DoNotOptimize(c1);
              benchmark::DoNotOptimize(c2);
              auto result = swap_ranges(c1.begin(), c1.end(), c2.begin(), c2.end());
              benchmark::DoNotOptimize(result);
              benchmark::DoNotOptimize(c1);
              benchmark::DoNotOptimize(c2);
            }
          })
          ->Arg(32)
          ->Arg(50) // non power-of-two
          ->Arg(1024)
          ->Arg(8192);
    };
    bm.operator()<std::vector<int>>("std::swap_ranges(vector<int>)", std_swap_ranges);
    bm.operator()<std::deque<int>>("std::swap_ranges(deque<int>)", std_swap_ranges);
    bm.operator()<std::list<int>>("std::swap_ranges(list<int>)", std_swap_ranges);
    bm.operator()<std::vector<int>>("rng::swap_ranges(vector<int>)", std::ranges::swap_ranges);
    bm.operator()<std::deque<int>>("rng::swap_ranges(deque<int>)", std::ranges::swap_ranges);
    bm.operator()<std::list<int>>("rng::swap_ranges(list<int>)", std::ranges::swap_ranges);
  }

  benchmark::Initialize(&argc, argv);
  benchmark::RunSpecifiedBenchmarks();
  benchmark::Shutdown();
  return 0;
}