ceph/src/boost/libs/compute/perf/perf_stl_saxpy.cpp

   1 //---------------------------------------------------------------------------//
   2 // Copyright (c) 2013-2014 Kyle Lutz <kyle.r.lutz@gmail.com>
   3 //
   4 // Distributed under the Boost Software License, Version 1.0
   5 // See accompanying file LICENSE_1_0.txt or copy at
   6 // http://www.boost.org/LICENSE_1_0.txt
   7 //
   8 // See http://boostorg.github.com/compute for more information.
   9 //---------------------------------------------------------------------------//
  10
  11 #include <algorithm>
  12 #include <iostream>
  13 #include <vector>
  14
  15 #include "perf.hpp"
  16
  17 float rand_float()
  18 {
  19     return (float(rand()) / float(RAND_MAX)) * 1000.f;
  20 }
  21
  22 // y <- alpha * x + y
  23 void serial_saxpy(size_t n, float alpha, const float *x, float *y)
  24 {
  25     for(size_t i = 0; i < n; i++){
  26         y[i] = alpha * x[i] + y[i];
  27     }
  28 }
  29
  30 int main(int argc, char *argv[])
  31 {
  32     perf_parse_args(argc, argv);
  33
  34     std::cout << "size: " << PERF_N << std::endl;
  35
  36     float alpha = 2.5f;
  37
  38     std::vector<float> host_x(PERF_N);
  39     std::vector<float> host_y(PERF_N);
  40     std::generate(host_x.begin(), host_x.end(), rand_float);
  41     std::generate(host_y.begin(), host_y.end(), rand_float);
  42
  43     perf_timer t;
  44     for(size_t trial = 0; trial < PERF_TRIALS; trial++){
  45         t.start();
  46         serial_saxpy(PERF_N, alpha, &host_x[0], &host_y[0]);
  47         t.stop();
  48     }
  49     std::cout << "time: " << t.min_time() / 1e6 << " ms" << std::endl;
  50
  51     return 0;
  52 }