117 lines
3.9 KiB
Plaintext
117 lines
3.9 KiB
Plaintext
|
//---------------------------------------------------------------------------//
|
||
|
|
// Copyright (c) 2014 Roshan <thisisroshansmail@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_DETAIL_MERGE_PATH_HPP
|
||
|
|
#define BOOST_COMPUTE_ALGORITHM_DETAIL_MERGE_PATH_HPP
|
||
|
|
|
||
|
|
#include <iterator>
|
||
|
|
|
||
|
|
#include <boost/compute/algorithm/find_if.hpp>
|
||
|
|
#include <boost/compute/container/vector.hpp>
|
||
|
|
#include <boost/compute/detail/iterator_range_size.hpp>
|
||
|
|
#include <boost/compute/detail/meta_kernel.hpp>
|
||
|
|
#include <boost/compute/lambda.hpp>
|
||
|
|
#include <boost/compute/system.hpp>
|
||
|
|
|
||
|
|
namespace boost {
|
||
|
|
namespace compute {
|
||
|
|
namespace detail {
|
||
|
|
|
||
|
|
///
|
||
|
|
/// \brief Merge Path kernel class
|
||
|
|
///
|
||
|
|
/// Subclass of meta_kernel to break two sets into tiles according
|
||
|
|
/// to their merge path
|
||
|
|
///
|
||
|
|
class merge_path_kernel : public meta_kernel
|
||
|
|
{
|
||
|
|
public:
|
||
|
|
unsigned int tile_size;
|
||
|
|
|
||
|
|
merge_path_kernel() : meta_kernel("merge_path")
|
||
|
|
{
|
||
|
|
tile_size = 4;
|
||
|
|
}
|
||
|
|
|
||
|
|
template<class InputIterator1, class InputIterator2,
|
||
|
|
class OutputIterator1, class OutputIterator2,
|
||
|
|
class Compare>
|
||
|
|
void set_range(InputIterator1 first1,
|
||
|
|
InputIterator1 last1,
|
||
|
|
InputIterator2 first2,
|
||
|
|
InputIterator2 last2,
|
||
|
|
OutputIterator1 result_a,
|
||
|
|
OutputIterator2 result_b,
|
||
|
|
Compare comp)
|
||
|
|
{
|
||
|
|
m_a_count = iterator_range_size(first1, last1);
|
||
|
|
m_a_count_arg = add_arg<uint_>("a_count");
|
||
|
|
|
||
|
|
m_b_count = iterator_range_size(first2, last2);
|
||
|
|
m_b_count_arg = add_arg<uint_>("b_count");
|
||
|
|
|
||
|
|
*this <<
|
||
|
|
"uint i = get_global_id(0);\n" <<
|
||
|
|
"uint target = (i+1)*" << tile_size << ";\n" <<
|
||
|
|
"uint start = max(convert_int(0),convert_int(target)-convert_int(b_count));\n" <<
|
||
|
|
"uint end = min(target,a_count);\n" <<
|
||
|
|
"uint a_index, b_index;\n" <<
|
||
|
|
"while(start<end)\n" <<
|
||
|
|
"{\n" <<
|
||
|
|
" a_index = (start + end)/2;\n" <<
|
||
|
|
" b_index = target - a_index - 1;\n" <<
|
||
|
|
" if(!(" << comp(first2[expr<uint_>("b_index")],
|
||
|
|
first1[expr<uint_>("a_index")]) << "))\n" <<
|
||
|
|
" start = a_index + 1;\n" <<
|
||
|
|
" else end = a_index;\n" <<
|
||
|
|
"}\n" <<
|
||
|
|
result_a[expr<uint_>("i")] << " = start;\n" <<
|
||
|
|
result_b[expr<uint_>("i")] << " = target - start;\n";
|
||
|
|
}
|
||
|
|
|
||
|
|
template<class InputIterator1, class InputIterator2,
|
||
|
|
class OutputIterator1, class OutputIterator2>
|
||
|
|
void set_range(InputIterator1 first1,
|
||
|
|
InputIterator1 last1,
|
||
|
|
InputIterator2 first2,
|
||
|
|
InputIterator2 last2,
|
||
|
|
OutputIterator1 result_a,
|
||
|
|
OutputIterator2 result_b)
|
||
|
|
{
|
||
|
|
typedef typename std::iterator_traits<InputIterator1>::value_type value_type;
|
||
|
|
::boost::compute::less<value_type> less_than;
|
||
|
|
set_range(first1, last1, first2, last2, result_a, result_b, less_than);
|
||
|
|
}
|
||
|
|
|
||
|
|
event exec(command_queue &queue)
|
||
|
|
{
|
||
|
|
if((m_a_count + m_b_count)/tile_size == 0) {
|
||
|
|
return event();
|
||
|
|
}
|
||
|
|
|
||
|
|
set_arg(m_a_count_arg, uint_(m_a_count));
|
||
|
|
set_arg(m_b_count_arg, uint_(m_b_count));
|
||
|
|
|
||
|
|
return exec_1d(queue, 0, (m_a_count + m_b_count)/tile_size);
|
||
|
|
}
|
||
|
|
|
||
|
|
private:
|
||
|
|
size_t m_a_count;
|
||
|
|
size_t m_a_count_arg;
|
||
|
|
size_t m_b_count;
|
||
|
|
size_t m_b_count_arg;
|
||
|
|
};
|
||
|
|
|
||
|
|
} //end detail namespace
|
||
|
|
} //end compute namespace
|
||
|
|
} //end boost namespace
|
||
|
|
|
||
|
|
#endif // BOOST_COMPUTE_ALGORITHM_DETAIL_MERGE_PATH_HPP
|