xref: /oneTBB/examples/parallel_reduce/primes/main.cpp (revision b15aabb3)

/*
    Copyright (c) 2005-2021 Intel Corporation

    Licensed under the Apache License, Version 2.0 (the "License");
    you may not use this file except in compliance with the License.
    You may obtain a copy of the License at

        http://www.apache.org/licenses/LICENSE-2.0

    Unless required by applicable law or agreed to in writing, software
    distributed under the License is distributed on an "AS IS" BASIS,
    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    See the License for the specific language governing permissions and
    limitations under the License.
*/

#include <cstdlib>
#include <cstdio>
#include <cstring>
#include <cctype>

#include <utility>
#include <iostream>
#include <sstream>

#include "oneapi/tbb/tick_count.h"

#include "common/utility/utility.hpp"

#include "primes.hpp"

struct RunOptions {
    //! NumberType of threads to use.
    utility::thread_number_range threads;
    //whether to suppress additional output
    bool silentFlag;
    //
    NumberType n;
    //! Grain size parameter
    NumberType grainSize;
    // number of time to repeat calculation
    NumberType repeatNumber;

    RunOptions(utility::thread_number_range threads_,
               NumberType grainSize_,
               NumberType n_,
               bool silentFlag_,
               NumberType repeatNumber_)
            : threads(threads_),
              silentFlag(silentFlag_),
              n(n_),
              grainSize(grainSize_),
              repeatNumber(repeatNumber_) {}
};

//! Parse the command line.
static RunOptions ParseCommandLine(int argc, char* argv[]) {
    utility::thread_number_range threads(
        utility::get_default_num_threads, 0, utility::get_default_num_threads());
    NumberType grainSize = 1000;
    bool silent = false;
    NumberType number = 100000000;
    NumberType repeatNumber = 1;

    utility::parse_cli_arguments(
        argc,
        argv,
        utility::cli_argument_pack()
            //"-h" option for displaying help is present implicitly
            .positional_arg(threads, "n-of-threads", utility::thread_number_range_desc)
            .positional_arg(number,
                            "number",
                            "upper bound of range to search primes in, must be a positive integer")
            .positional_arg(grainSize, "grain-size", "must be a positive integer")
            .positional_arg(
                repeatNumber,
                "n-of-repeats",
                "repeat the calculation this number of times, must be a positive integer")
            .arg(silent, "silent", "no output except elapsed time"));

    RunOptions options(threads, grainSize, number, silent, repeatNumber);
    return options;
}

int main(int argc, char* argv[]) {
    oneapi::tbb::tick_count mainBeginMark = oneapi::tbb::tick_count::now();
    RunOptions options = ParseCommandLine(argc, argv);

    // Try different numbers of threads
    for (int p = options.threads.first; p <= options.threads.last; p = options.threads.step(p)) {
        for (NumberType i = 0; i < options.repeatNumber; ++i) {
            oneapi::tbb::tick_count iterationBeginMark = oneapi::tbb::tick_count::now();
            NumberType count = 0;
            NumberType n = options.n;
            if (p == 0) {
                count = SerialCountPrimes(n);
            }
            else {
                NumberType grainSize = options.grainSize;
                count = ParallelCountPrimes(n, p, grainSize);
            }
            oneapi::tbb::tick_count iterationEndMark = oneapi::tbb::tick_count::now();
            if (!options.silentFlag) {
                std::cout << "#primes from [2.." << options.n << "] = " << count << " ("
                          << (iterationEndMark - iterationBeginMark).seconds() << " sec with ";
                if (0 != p)
                    std::cout << p << "-way parallelism";
                else
                    std::cout << "serial code";
                std::cout << ")\n";
            }
        }
    }
    utility::report_elapsed_time((oneapi::tbb::tick_count::now() - mainBeginMark).seconds());
    return 0;
}