ceph/src/boost/libs/local_function/example/profile_local_functor.cpp

   1
   2 // Copyright (C) 2009-2012 Lorenzo Caminiti
   3 // Distributed under the Boost Software License, Version 1.0
   4 // (see accompanying file LICENSE_1_0.txt or a copy at
   5 // http://www.boost.org/LICENSE_1_0.txt)
   6 // Home at http://www.boost.org/libs/local_function
   7
   8 #include <boost/chrono.hpp>
   9 #include <vector>
  10 #include <algorithm>
  11 #include <iostream>
  12 #include "profile_helpers.hpp"
  13
  14 int main(int argc, char* argv[]) {
  15     unsigned long size = 0, trials = 0;
  16     profile::args(argc, argv, size, trials);
  17
  18     double sum = 0.0;
  19     int factor = 1;
  20
  21     boost::chrono::system_clock::time_point start =
  22             boost::chrono::system_clock::now();
  23     struct local_add {
  24         local_add(double& _sum, const int& _factor):
  25                 sum(_sum), factor(_factor) {}
  26         inline void operator()(const double& num) {
  27             sum += factor * num;
  28         }
  29     private:
  30         double& sum;
  31         const int& factor;
  32     } add(sum, factor);
  33     boost::chrono::duration<double> decl_sec =
  34             boost::chrono::system_clock::now() - start;
  35
  36     std::vector<double> v(size);
  37     std::fill(v.begin(), v.end(), 1.0);
  38
  39     boost::chrono::duration<double> trials_sec;
  40     for(unsigned long i = 0; i < trials; ++i) {
  41         boost::chrono::system_clock::time_point start =
  42                 boost::chrono::system_clock::now();
  43         for(unsigned long j = 0; j < v.size(); ++j) add(v[j]); // No for_each.
  44         trials_sec += boost::chrono::system_clock::now() - start;
  45     }
  46
  47     profile::display(size, trials, sum, trials_sec.count(), decl_sec.count());
  48     return 0;
  49 }
  50