lib/Catch2/src/catch2/benchmark/catch_execution_plan.hpp

//              Copyright Catch2 Authors
// Distributed under the Boost Software License, Version 1.0.
//   (See accompanying file LICENSE.txt or copy at
//        https://www.boost.org/LICENSE_1_0.txt)

// SPDX-License-Identifier: BSL-1.0
// Adapted from donated nonius code.

#ifndef CATCH_EXECUTION_PLAN_HPP_INCLUDED
#define CATCH_EXECUTION_PLAN_HPP_INCLUDED

#include <catch2/interfaces/catch_interfaces_config.hpp>
#include <catch2/benchmark/catch_clock.hpp>
#include <catch2/benchmark/catch_environment.hpp>
#include <catch2/benchmark/detail/catch_benchmark_function.hpp>
#include <catch2/benchmark/detail/catch_repeat.hpp>
#include <catch2/benchmark/detail/catch_run_for_at_least.hpp>

#include <vector>

namespace Catch {
    namespace Benchmark {
        struct ExecutionPlan {
            int iterations_per_sample;
            FDuration estimated_duration;
            Detail::BenchmarkFunction benchmark;
            FDuration warmup_time;
            int warmup_iterations;

            template <typename Clock>
            std::vector<FDuration> run(const IConfig &cfg, Environment env) const {
                // warmup a bit
                Detail::run_for_at_least<Clock>(
                    std::chrono::duration_cast<IDuration>( warmup_time ),
                    warmup_iterations,
                    Detail::repeat( []() { return Clock::now(); } )
                );

                std::vector<FDuration> times;
                const auto num_samples = cfg.benchmarkSamples();
                times.reserve( num_samples );
                for ( size_t i = 0; i < num_samples; ++i ) {
                    Detail::ChronometerModel<Clock> model;
                    this->benchmark( Chronometer( model, iterations_per_sample ) );
                    auto sample_time = model.elapsed() - env.clock_cost.mean;
                    if ( sample_time < FDuration::zero() ) {
                        sample_time = FDuration::zero();
                    }
                    times.push_back(sample_time / iterations_per_sample);
                }
                return times;
            }
        };
    } // namespace Benchmark
} // namespace Catch

#endif // CATCH_EXECUTION_PLAN_HPP_INCLUDED