catch2/benchmark/catch_chronometer.hpp

0001
0002 //              Copyright Catch2 Authors
0003 // Distributed under the Boost Software License, Version 1.0.
0004 //   (See accompanying file LICENSE.txt or copy at
0005 //        https://www.boost.org/LICENSE_1_0.txt)
0006
0007 // SPDX-License-Identifier: BSL-1.0
0008 // Adapted from donated nonius code.
0009
0010 #ifndef CATCH_CHRONOMETER_HPP_INCLUDED
0011 #define CATCH_CHRONOMETER_HPP_INCLUDED
0012
0013 #include <catch2/benchmark/catch_clock.hpp>
0014 #include <catch2/benchmark/catch_optimizer.hpp>
0015 #include <catch2/internal/catch_meta.hpp>
0016 #include <catch2/internal/catch_move_and_forward.hpp>
0017
0018 namespace Catch {
0019     namespace Benchmark {
0020         namespace Detail {
0021             struct ChronometerConcept {
0022                 virtual void start() = 0;
0023                 virtual void finish() = 0;
0024                 virtual ~ChronometerConcept(); // = default;
0025
0026                 ChronometerConcept() = default;
0027                 ChronometerConcept(ChronometerConcept const&) = default;
0028                 ChronometerConcept& operator=(ChronometerConcept const&) = default;
0029             };
0030             template <typename Clock>
0031             struct ChronometerModel final : public ChronometerConcept {
0032                 void start() override { started = Clock::now(); }
0033                 void finish() override { finished = Clock::now(); }
0034
0035                 ClockDuration<Clock> elapsed() const { return finished - started; }
0036
0037                 TimePoint<Clock> started;
0038                 TimePoint<Clock> finished;
0039             };
0040         } // namespace Detail
0041
0042         struct Chronometer {
0043         public:
0044             template <typename Fun>
0045             void measure(Fun&& fun) { measure(CATCH_FORWARD(fun), is_callable<Fun(int)>()); }
0046
0047             int runs() const { return repeats; }
0048
0049             Chronometer(Detail::ChronometerConcept& meter, int repeats_)
0050                 : impl(&meter)
0051                 , repeats(repeats_) {}
0052
0053         private:
0054             template <typename Fun>
0055             void measure(Fun&& fun, std::false_type) {
0056                 measure([&fun](int) { return fun(); }, std::true_type());
0057             }
0058
0059             template <typename Fun>
0060             void measure(Fun&& fun, std::true_type) {
0061                 Detail::optimizer_barrier();
0062                 impl->start();
0063                 for (int i = 0; i < repeats; ++i) invoke_deoptimized(fun, i);
0064                 impl->finish();
0065                 Detail::optimizer_barrier();
0066             }
0067
0068             Detail::ChronometerConcept* impl;
0069             int repeats;
0070         };
0071     } // namespace Benchmark
0072 } // namespace Catch
0073
0074 #endif // CATCH_CHRONOMETER_HPP_INCLUDED