//---------------------------------------------------------------------------// // Copyright (c) 2013 Kyle Lutz <kyle.r.lutz@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. //---------------------------------------------------------------------------// #ifndef BOOST_COMPUTE_ALGORITHM_INPLACE_MERGE_HPP #define BOOST_COMPUTE_ALGORITHM_INPLACE_MERGE_HPP #include <iterator> #include <boost/static_assert.hpp> #include <boost/compute/system.hpp> #include <boost/compute/command_queue.hpp> #include <boost/compute/algorithm/merge.hpp> #include <boost/compute/container/vector.hpp> #include <boost/compute/type_traits/is_device_iterator.hpp> namespace boost { namespace compute { /// Merges the sorted values in the range [\p first, \p middle) with /// the sorted values in the range [\p middle, \p last) in-place. /// /// Space complexity: \Omega(n) template<class Iterator> inline void inplace_merge(Iterator first, Iterator middle, Iterator last, command_queue &queue = system::default_queue()) { BOOST_STATIC_ASSERT(is_device_iterator<Iterator>::value); BOOST_ASSERT(first < middle && middle < last); typedef typename std::iterator_traits<Iterator>::value_type T; const context &context = queue.get_context(); ptrdiff_t left_size = std::distance(first, middle); ptrdiff_t right_size = std::distance(middle, last); vector<T> left(left_size, context); vector<T> right(right_size, context); copy(first, middle, left.begin(), queue); copy(middle, last, right.begin(), queue); ::boost::compute::merge( left.begin(), left.end(), right.begin(), right.end(), first, queue ); } } // end compute namespace } // end boost namespace #endif // BOOST_COMPUTE_ALGORITHM_INPLACE_MERGE_HPP