ceph/src/boost/boost/compute/algorithm/partial_sum.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_PARTIAL_SUM_HPP
  12 #define BOOST_COMPUTE_ALGORITHM_PARTIAL_SUM_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/inclusive_scan.hpp>
  19 #include <boost/compute/type_traits/is_device_iterator.hpp>
  20
  21 namespace boost {
  22 namespace compute {
  23
  24 /// Calculates the cumulative sum of the elements in the range [\p first,
  25 /// \p last) and writes the resulting values to the range beginning at
  26 /// \p result.
  27 ///
  28 /// Space complexity on GPUs: \Omega(n)<br>
  29 /// Space complexity on GPUs when \p first == \p result: \Omega(2n)<br>
  30 /// Space complexity on CPUs: \Omega(1)
  31 template<class InputIterator, class OutputIterator>
  32 inline OutputIterator
  33 partial_sum(InputIterator first,
  34             InputIterator last,
  35             OutputIterator result,
  36             command_queue &queue = system::default_queue())
  37 {
  38     BOOST_STATIC_ASSERT(is_device_iterator<InputIterator>::value);
  39     BOOST_STATIC_ASSERT(is_device_iterator<OutputIterator>::value);
  40     return ::boost::compute::inclusive_scan(first, last, result, queue);
  41 }
  42
  43 } // end compute namespace
  44 } // end boost namespace
  45
  46 #endif // BOOST_COMPUTE_ALGORITHM_PARTIAL_SUM_HPP