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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 <iterator>
#include <list>
#include <string>
#include <vector>
#include "benchmark/benchmark.h"
#include "../../GenerateInput.h"
int main(int argc, char** argv) {
auto std_copy_if = [](auto first, auto last, auto out, auto pred) { return std::copy_if(first, last, out, pred); };
// Benchmark {std,ranges}::copy_if where we copy one out of two element, in alternance.
// This is basically the worst case for this algorithm, I don't think there are many
// optimizations that can be applied in this case.
{
auto bm = []<class Container>(std::string name, auto copy_if) {
benchmark::RegisterBenchmark(name, [copy_if](auto& st) {
std::size_t const n = st.range(0);
using ValueType = typename Container::value_type;
Container c;
std::generate_n(std::back_inserter(c), n, [] { return Generate<ValueType>::random(); });
std::vector<ValueType> out(n);
for ([[maybe_unused]] auto _ : st) {
bool do_copy = false;
auto pred = [&do_copy](auto& element) {
benchmark::DoNotOptimize(element);
do_copy = !do_copy;
return do_copy;
};
benchmark::DoNotOptimize(c);
benchmark::DoNotOptimize(out);
auto result = copy_if(c.begin(), c.end(), out.begin(), pred);
benchmark::DoNotOptimize(result);
}
})->Range(8, 1 << 20);
};
bm.operator()<std::vector<int>>("std::copy_if(vector<int>) (every other)", std_copy_if);
bm.operator()<std::deque<int>>("std::copy_if(deque<int>) (every other)", std_copy_if);
bm.operator()<std::list<int>>("std::copy_if(list<int>) (every other)", std_copy_if);
bm.operator()<std::vector<int>>("rng::copy_if(vector<int>) (every other)", std::ranges::copy_if);
bm.operator()<std::deque<int>>("rng::copy_if(deque<int>) (every other)", std::ranges::copy_if);
bm.operator()<std::list<int>>("rng::copy_if(list<int>) (every other)", std::ranges::copy_if);
}
// Benchmark {std,ranges}::copy_if where we copy the full range.
// Copy the full range.
{
auto bm = []<class Container>(std::string name, auto copy_if) {
benchmark::RegisterBenchmark(name, [copy_if](auto& st) {
std::size_t const n = st.range(0);
using ValueType = typename Container::value_type;
Container c;
std::generate_n(std::back_inserter(c), n, [] { return Generate<ValueType>::random(); });
std::vector<ValueType> out(n);
for ([[maybe_unused]] auto _ : st) {
auto pred = [](auto& element) {
benchmark::DoNotOptimize(element);
return true;
};
benchmark::DoNotOptimize(c);
benchmark::DoNotOptimize(out);
auto result = copy_if(c.begin(), c.end(), out.begin(), pred);
benchmark::DoNotOptimize(result);
}
})->Range(8, 1 << 20);
};
bm.operator()<std::vector<int>>("std::copy_if(vector<int>) (entire range)", std_copy_if);
bm.operator()<std::deque<int>>("std::copy_if(deque<int>) (entire range)", std_copy_if);
bm.operator()<std::list<int>>("std::copy_if(list<int>) (entire range)", std_copy_if);
bm.operator()<std::vector<int>>("rng::copy_if(vector<int>) (entire range)", std::ranges::copy_if);
bm.operator()<std::deque<int>>("rng::copy_if(deque<int>) (entire range)", std::ranges::copy_if);
bm.operator()<std::list<int>>("rng::copy_if(list<int>) (entire range)", std::ranges::copy_if);
}
benchmark::Initialize(&argc, argv);
benchmark::RunSpecifiedBenchmarks();
benchmark::Shutdown();
return 0;
}
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