ceph/src/boost/boost/compute/algorithm/swap_ranges.hpp

   1 //---------------------------------------------------------------------------//
   2 // Copyright (c) 2013 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 #ifndef BOOST_COMPUTE_ALGORITHM_SWAP_RANGES_HPP
  12 #define BOOST_COMPUTE_ALGORITHM_SWAP_RANGES_HPP
  13
  14 #include <boost/static_assert.hpp>
  15
  16 #include <boost/compute/system.hpp>
  17 #include <boost/compute/command_queue.hpp>
  18 #include <boost/compute/algorithm/copy.hpp>
  19 #include <boost/compute/container/vector.hpp>
  20 #include <boost/compute/type_traits/is_device_iterator.hpp>
  21
  22 namespace boost {
  23 namespace compute {
  24
  25 /// Swaps the elements in the range [\p first1, \p last1) with the
  26 /// elements in the range beginning at \p first2.
  27 ///
  28 /// Space complexity: \Omega(distance(\p first1, \p last1))
  29 template<class Iterator1, class Iterator2>
  30 inline Iterator2 swap_ranges(Iterator1 first1,
  31                              Iterator1 last1,
  32                              Iterator2 first2,
  33                              command_queue &queue = system::default_queue())
  34 {
  35     BOOST_STATIC_ASSERT(is_device_iterator<Iterator1>::value);
  36     BOOST_STATIC_ASSERT(is_device_iterator<Iterator2>::value);
  37
  38     typedef typename std::iterator_traits<Iterator1>::value_type value_type;
  39
  40     Iterator2 last2 = first2 + std::distance(first1, last1);
  41
  42     ::boost::compute::vector<value_type> tmp(first1, last1, queue);
  43     ::boost::compute::copy(first2, last2, first1, queue);
  44     ::boost::compute::copy(tmp.begin(), tmp.end(), first2, queue);
  45
  46     return last2;
  47 }
  48
  49 } // end compute namespace
  50 } // end boost namespace
  51
  52 #endif // BOOST_COMPUTE_ALGORITHM_SWAP_RANGES_HPP