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

   1 //---------------------------------------------------------------------------//
   2 // Copyright (c) 2014 Roshan <thisisroshansmail@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 <numeric>
  14 #include <vector>
  15
  16 #include <boost/compute/system.hpp>
  17 #include <boost/compute/algorithm/next_permutation.hpp>
  18 #include <boost/compute/algorithm/prev_permutation.hpp>
  19 #include <boost/compute/container/vector.hpp>
  20
  21 #include "perf.hpp"
  22
  23 int rand_int()
  24 {
  25     return static_cast<int>((rand() / double(RAND_MAX)) * 25.0);
  26 }
  27
  28 int main(int argc, char *argv[])
  29 {
  30     perf_parse_args(argc, argv);
  31     std::cout << "size: " << PERF_N << std::endl;
  32
  33     // setup context and queue for the default device
  34     boost::compute::device device = boost::compute::system::default_device();
  35     boost::compute::context context(device);
  36     boost::compute::command_queue queue(context, device);
  37     std::cout << "device: " << device.name() << std::endl;
  38
  39     // create vector of random numbers on the host
  40     std::vector<int> host_vector(PERF_N);
  41     std::generate(host_vector.begin(), host_vector.end(), rand_int);
  42     std::sort(host_vector.begin(), host_vector.end());
  43
  44     // create vector on the device and copy the data
  45     boost::compute::vector<int> device_vector(PERF_N, context);
  46     boost::compute::copy(
  47         host_vector.begin(), host_vector.end(), device_vector.begin(), queue
  48     );
  49
  50     perf_timer t;
  51     for(size_t trial = 0; trial < PERF_TRIALS; trial++){
  52         t.start();
  53         boost::compute::prev_permutation(
  54             device_vector.begin(), device_vector.end(), queue
  55         );
  56         queue.finish();
  57         t.stop();
  58         boost::compute::next_permutation(
  59             device_vector.begin(), device_vector.end(), queue
  60         );
  61     }
  62     std::cout << "time: " << t.min_time() / 1e6 << " ms" << std::endl;
  63
  64     return 0;
  65 }