104 lines
3.2 KiB
Plaintext
104 lines
3.2 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_SERIAL_SCAN_HPP
|
|
#define BOOST_COMPUTE_ALGORITHM_DETAIL_SERIAL_SCAN_HPP
|
|
|
|
#include <iterator>
|
|
|
|
#include <boost/compute/device.hpp>
|
|
#include <boost/compute/kernel.hpp>
|
|
#include <boost/compute/command_queue.hpp>
|
|
#include <boost/compute/detail/meta_kernel.hpp>
|
|
#include <boost/compute/detail/iterator_range_size.hpp>
|
|
|
|
namespace boost {
|
|
namespace compute {
|
|
namespace detail {
|
|
|
|
template<class InputIterator, class OutputIterator, class T, class BinaryOperator>
|
|
inline OutputIterator serial_scan(InputIterator first,
|
|
InputIterator last,
|
|
OutputIterator result,
|
|
bool exclusive,
|
|
T init,
|
|
BinaryOperator op,
|
|
command_queue &queue)
|
|
{
|
|
if(first == last){
|
|
return result;
|
|
}
|
|
|
|
typedef typename
|
|
std::iterator_traits<InputIterator>::value_type input_type;
|
|
typedef typename
|
|
std::iterator_traits<OutputIterator>::value_type output_type;
|
|
|
|
const context &context = queue.get_context();
|
|
|
|
// create scan kernel
|
|
meta_kernel k("serial_scan");
|
|
|
|
// Arguments
|
|
size_t n_arg = k.add_arg<ulong_>("n");
|
|
size_t init_arg = k.add_arg<output_type>("initial_value");
|
|
|
|
if(!exclusive){
|
|
k <<
|
|
k.decl<const ulong_>("start_idx") << " = 1;\n" <<
|
|
k.decl<output_type>("sum") << " = " << first[0] << ";\n" <<
|
|
result[0] << " = sum;\n";
|
|
}
|
|
else {
|
|
k <<
|
|
k.decl<const ulong_>("start_idx") << " = 0;\n" <<
|
|
k.decl<output_type>("sum") << " = initial_value;\n";
|
|
}
|
|
|
|
k <<
|
|
"for(ulong i = start_idx; i < n; i++){\n" <<
|
|
k.decl<const input_type>("x") << " = "
|
|
<< first[k.var<ulong_>("i")] << ";\n";
|
|
|
|
if(exclusive){
|
|
k << result[k.var<ulong_>("i")] << " = sum;\n";
|
|
}
|
|
|
|
k << " sum = "
|
|
<< op(k.var<output_type>("sum"), k.var<output_type>("x"))
|
|
<< ";\n";
|
|
|
|
if(!exclusive){
|
|
k << result[k.var<ulong_>("i")] << " = sum;\n";
|
|
}
|
|
|
|
k << "}\n";
|
|
|
|
// compile scan kernel
|
|
kernel scan_kernel = k.compile(context);
|
|
|
|
// setup kernel arguments
|
|
size_t n = detail::iterator_range_size(first, last);
|
|
scan_kernel.set_arg<ulong_>(n_arg, n);
|
|
scan_kernel.set_arg<output_type>(init_arg, static_cast<output_type>(init));
|
|
|
|
// execute the kernel
|
|
queue.enqueue_1d_range_kernel(scan_kernel, 0, 1, 1);
|
|
|
|
// return iterator pointing to the end of the result range
|
|
return result + n;
|
|
}
|
|
|
|
} // end detail namespace
|
|
} // end compute namespace
|
|
} // end boost namespace
|
|
|
|
#endif // BOOST_COMPUTE_ALGORITHM_DETAIL_SERIAL_SCAN_HPP
|