79 lines
2.6 KiB
Plaintext
79 lines
2.6 KiB
Plaintext
//---------------------------------------------------------------------------//
|
|
// 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_DETAIL_COUNT_IF_WITH_BALLOT_HPP
|
|
#define BOOST_COMPUTE_ALGORITHM_DETAIL_COUNT_IF_WITH_BALLOT_HPP
|
|
|
|
#include <boost/compute/context.hpp>
|
|
#include <boost/compute/command_queue.hpp>
|
|
#include <boost/compute/container/vector.hpp>
|
|
#include <boost/compute/algorithm/reduce.hpp>
|
|
#include <boost/compute/functional/detail/nvidia_ballot.hpp>
|
|
#include <boost/compute/functional/detail/nvidia_popcount.hpp>
|
|
#include <boost/compute/detail/meta_kernel.hpp>
|
|
|
|
namespace boost {
|
|
namespace compute {
|
|
namespace detail {
|
|
|
|
template<class InputIterator, class Predicate>
|
|
inline size_t count_if_with_ballot(InputIterator first,
|
|
InputIterator last,
|
|
Predicate predicate,
|
|
command_queue &queue)
|
|
{
|
|
size_t count = iterator_range_size(first, last);
|
|
size_t block_size = 32;
|
|
size_t block_count = count / block_size;
|
|
if(block_count * block_size != count){
|
|
block_count++;
|
|
}
|
|
|
|
const ::boost::compute::context &context = queue.get_context();
|
|
|
|
::boost::compute::vector<uint_> counts(block_count, context);
|
|
|
|
::boost::compute::detail::nvidia_popcount<uint_> popc;
|
|
::boost::compute::detail::nvidia_ballot<uint_> ballot;
|
|
|
|
meta_kernel k("count_if_with_ballot");
|
|
k <<
|
|
"const uint gid = get_global_id(0);\n" <<
|
|
|
|
"bool value = false;\n" <<
|
|
"if(gid < count)\n" <<
|
|
" value = " << predicate(first[k.var<const uint_>("gid")]) << ";\n" <<
|
|
|
|
"uint bits = " << ballot(k.var<const uint_>("value")) << ";\n" <<
|
|
|
|
"if(get_local_id(0) == 0)\n" <<
|
|
counts.begin()[k.var<uint_>("get_group_id(0)") ]
|
|
<< " = " << popc(k.var<uint_>("bits")) << ";\n";
|
|
|
|
k.add_set_arg<const uint_>("count", count);
|
|
|
|
k.exec_1d(queue, 0, block_size * block_count, block_size);
|
|
|
|
uint_ result;
|
|
::boost::compute::reduce(
|
|
counts.begin(),
|
|
counts.end(),
|
|
&result,
|
|
queue
|
|
);
|
|
return result;
|
|
}
|
|
|
|
} // end detail namespace
|
|
} // end compute namespace
|
|
} // end boost namespace
|
|
|
|
#endif // BOOST_COMPUTE_ALGORITHM_DETAIL_COUNT_IF_WITH_BALLOT_HPP
|