/usr/include/boost/compute/algorithm/detail
Edit: /usr/include/boost/compute/algorithm/detail/count_if_with_ballot.hpp (2605B)
//---------------------------------------------------------------------------//
// Copyright (c) 2013 Kyle Lutz
//
// 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
#include
#include
#include
#include
#include
#include
namespace boost {
namespace compute {
namespace detail {
template
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 counts(block_count, context);
::boost::compute::detail::nvidia_popcount popc;
::boost::compute::detail::nvidia_ballot 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("gid")]) << ";\n" <<
"uint bits = " << ballot(k.var("value")) << ";\n" <<
"if(get_local_id(0) == 0)\n" <<
counts.begin()[k.var("get_group_id(0)") ]
<< " = " << popc(k.var("bits")) << ";\n";
k.add_set_arg("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