compute/perf/perf_max_element.cpp

94 lines
2.9 KiB
C++

//---------------------------------------------------------------------------//
// Copyright (c) 2013-2014 Rastko Anicic <anicic.rastko@gmail.com>
//
// Distributed under the Boost Software License, Version 1.0
// See accompanying file LICENSE_1_0.txt or copy at
// http://www.boost.org/LICENSE_1_0.txt
//
// See http://boostorg.github.com/compute for more information.
//---------------------------------------------------------------------------//
#include <algorithm>
#include <iostream>
#include <vector>
#include <boost/compute/system.hpp>
#include <boost/compute/algorithm/max_element.hpp>
#include <boost/compute/container/vector.hpp>
#include "perf.hpp"
int rand_int()
{
return static_cast<int>(rand() % 10000000);
}
int main(int argc, char *argv[])
{
perf_parse_args(argc, argv);
std::cout << "size: " << PERF_N << std::endl;
// setup context and queue for the default device
boost::compute::device device = boost::compute::system::default_device();
boost::compute::context context(device);
boost::compute::command_queue queue(context, device);
std::cout << "device: " << device.name() << std::endl;
// create vector of random numbers on the host
std::vector<int> host_vector(PERF_N);
std::generate(host_vector.begin(), host_vector.end(), rand_int);
// create vector on the device and copy the data
boost::compute::vector<int> device_vector(PERF_N, context);
boost::compute::copy(
host_vector.begin(),
host_vector.end(),
device_vector.begin(),
queue
);
boost::compute::vector<int>::iterator device_max_iter
= device_vector.begin();
perf_timer t;
for(size_t trial = 0; trial < PERF_TRIALS; trial++){
t.start();
device_max_iter = boost::compute::max_element(
device_vector.begin(), device_vector.end(), queue
);
queue.finish();
t.stop();
}
int device_max = device_max_iter.read(queue);
std::cout << "time: " << t.min_time() / 1e6 << " ms" << std::endl;
std::cout << "max: " << device_max << std::endl;
// verify max is correct
std::vector<int>::iterator host_max_iter
= std::max_element(host_vector.begin(), host_vector.end());
int host_max = *host_max_iter;
if(device_max != host_max){
std::cout << "ERROR: "
<< "device_max (" << device_max << ") "
<< "!= "
<< "host_max (" << host_max << ")"
<< std::endl;
return -1;
}
size_t host_max_idx = std::distance(host_vector.begin(), host_max_iter);
size_t device_max_idx = std::distance(device_vector.begin(), device_max_iter);
if(device_max_idx != host_max_idx){
std::cout << "ERROR: "
<< "device_max index (" << device_max_idx << ") "
<< "!= "
<< "host_max index (" << host_max_idx << ")"
<< std::endl;
return -1;
}
return 0;
}