85 lines · cpp
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-exception6//7//===----------------------------------------------------------------------===//8 9// UNSUPPORTED: c++03, c++11, c++14, c++1710 11#include <algorithm>12#include <cstddef>13#include <deque>14#include <iterator>15#include <list>16#include <string>17#include <vector>18 19#include "benchmark/benchmark.h"20#include "../../GenerateInput.h"21#include "test_macros.h"22 23int main(int argc, char** argv) {24 auto std_copy_backward = [](auto first, auto last, auto out) { return std::copy_backward(first, last, out); };25 26 // {std,ranges}::copy_n(normal container)27 {28 auto bm = []<class Container>(std::string name, auto copy_backward) {29 benchmark::RegisterBenchmark(name, [copy_backward](auto& st) {30 std::size_t const n = st.range(0);31 using ValueType = typename Container::value_type;32 Container c;33 std::generate_n(std::back_inserter(c), n, [] { return Generate<ValueType>::random(); });34 35 std::vector<ValueType> out(n);36 37 for ([[maybe_unused]] auto _ : st) {38 benchmark::DoNotOptimize(c);39 benchmark::DoNotOptimize(out);40 auto result = copy_backward(c.begin(), c.end(), out.end());41 benchmark::DoNotOptimize(result);42 }43 })->Range(8, 1 << 20);44 };45 bm.operator()<std::vector<int>>("std::copy_backward(vector<int>)", std_copy_backward);46 bm.operator()<std::deque<int>>("std::copy_backward(deque<int>)", std_copy_backward);47 bm.operator()<std::list<int>>("std::copy_backward(list<int>)", std_copy_backward);48 bm.operator()<std::vector<int>>("rng::copy_backward(vector<int>)", std::ranges::copy_backward);49 bm.operator()<std::deque<int>>("rng::copy_backward(deque<int>)", std::ranges::copy_backward);50 bm.operator()<std::list<int>>("rng::copy_backward(list<int>)", std::ranges::copy_backward);51 }52 53 // {std,ranges}::copy_n(vector<bool>)54 {55 auto bm = []<bool Aligned>(std::string name, auto copy_backward) {56 benchmark::RegisterBenchmark(name, [copy_backward](auto& st) {57 std::size_t const n = st.range(0);58 std::vector<bool> in(n, true);59 std::vector<bool> out(Aligned ? n : n + 8);60 benchmark::DoNotOptimize(&in);61 auto first = in.begin();62 auto last = in.end();63 auto dst = Aligned ? out.end() : out.end() - 4;64 for ([[maybe_unused]] auto _ : st) {65 benchmark::DoNotOptimize(in);66 benchmark::DoNotOptimize(out);67 auto result = copy_backward(first, last, dst);68 benchmark::DoNotOptimize(result);69 }70 })->Range(64, 1 << 20);71 };72 bm.operator()<true>("std::copy_backward(vector<bool>) (aligned)", std_copy_backward);73 bm.operator()<false>("std::copy_backward(vector<bool>) (unaligned)", std_copy_backward);74#if TEST_STD_VER >= 23 // vector<bool>::iterator is not an output_iterator before C++2375 bm.operator()<true>("rng::copy_backward(vector<bool>) (aligned)", std::ranges::copy_backward);76 bm.operator()<false>("rng::copy_backward(vector<bool>) (unaligned)", std::ranges::copy_backward);77#endif78 }79 80 benchmark::Initialize(&argc, argv);81 benchmark::RunSpecifiedBenchmarks();82 benchmark::Shutdown();83 return 0;84}85