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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
// UNSUPPORTED: no-filesystem, no-localization, no-tzdb
// XFAIL: libcpp-has-no-experimental-tzdb
// XFAIL: availability-tzdb-missing
#include <chrono>
#include "benchmark/benchmark.h"
// Benchmarks the performance of the UTC <-> system time conversions. These
// operations determine the sum of leap second insertions at a specific time.
static void BM_from_sys(benchmark::State& state) {
std::chrono::sys_days date{std::chrono::July / 1 / state.range(0)};
for (auto _ : state)
benchmark::DoNotOptimize(std::chrono::utc_clock::from_sys(date));
}
BENCHMARK(BM_from_sys)
->Arg(1970) // before the first leap seconds
->Arg(1979) // in the first half of inserted leap seconds
->Arg(1993) // in the second half of inserted leap seconds
->Arg(2100); // after the last leap second
BENCHMARK(BM_from_sys)->Arg(1970)->Arg(1979)->Arg(1993)->Arg(2100)->Threads(4);
BENCHMARK(BM_from_sys)->Arg(1970)->Arg(1979)->Arg(1993)->Arg(2100)->Threads(16);
static void BM_to_sys(benchmark::State& state) {
// 59 sec offset means we pass th UTC offset for the leap second; assuming
// there won't be more than 59 leap seconds ever.
std::chrono::utc_seconds date{
std::chrono::sys_days{std::chrono::July / 1 / state.range(0)}.time_since_epoch() + std::chrono::seconds{59}};
for (auto _ : state)
benchmark::DoNotOptimize(std::chrono::utc_clock::to_sys(date));
}
BENCHMARK(BM_to_sys)
->Arg(1970) // before the first leap seconds
->Arg(1979) // in the first half of inserted leap seconds
->Arg(1993) // in the second half of inserted leap seconds
->Arg(2100); // after the last leap second
BENCHMARK(BM_to_sys)->Arg(1970)->Arg(1979)->Arg(1993)->Arg(2100)->Threads(4);
BENCHMARK(BM_to_sys)->Arg(1970)->Arg(1979)->Arg(1993)->Arg(2100)->Threads(16);
int main(int argc, char** argv) {
benchmark::Initialize(&argc, argv);
if (benchmark::ReportUnrecognizedArguments(argc, argv))
return 1;
benchmark::RunSpecifiedBenchmarks();
}
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