/usr/include/boost/compute/algorithm
Edit: /usr/include/boost/compute/algorithm/lexicographical_compare.hpp (4950B)
//---------------------------------------------------------------------------//
// Copyright (c) 2014 Mageswaran.D
//
// 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.
//---------------------------------------------------------------------------//
#include
#include
#include
#include
#include
#include
#include
#include
namespace boost {
namespace compute {
namespace detail {
const char lexicographical_compare_source[] =
"__kernel void lexicographical_compare(const uint size1,\n"
" const uint size2,\n"
" __global const T1 *range1,\n"
" __global const T2 *range2,\n"
" __global bool *result_buf)\n"
"{\n"
" const uint i = get_global_id(0);\n"
" if((i != size1) && (i != size2)){\n"
//Individual elements are compared and results are stored in parallel.
//0 is true
" if(range1[i] < range2[i])\n"
" result_buf[i] = 0;\n"
" else\n"
" result_buf[i] = 1;\n"
" }\n"
" else\n"
" result_buf[i] = !((i == size1) && (i != size2));\n"
"}\n";
template
inline bool dispatch_lexicographical_compare(InputIterator1 first1,
InputIterator1 last1,
InputIterator2 first2,
InputIterator2 last2,
command_queue &queue)
{
const boost::compute::context &context = queue.get_context();
boost::shared_ptr cache =
program_cache::get_global_cache(context);
size_t iterator_size1 = iterator_range_size(first1, last1);
size_t iterator_size2 = iterator_range_size(first2, last2);
size_t max_size = (std::max)(iterator_size1, iterator_size2);
if(max_size == 0){
return false;
}
boost::compute::vector result_vector(max_size, context);
typedef typename std::iterator_traits::value_type value_type1;
typedef typename std::iterator_traits::value_type value_type2;
// load (or create) lexicographical compare program
std::string cache_key =
std::string("__boost_lexicographical_compare")
+ type_name() + type_name();
std::stringstream options;
options << " -DT1=" << type_name();
options << " -DT2=" << type_name();
program lexicographical_compare_program = cache->get_or_build(
cache_key, options.str(), lexicographical_compare_source, context
);
kernel lexicographical_compare_kernel(lexicographical_compare_program,
"lexicographical_compare");
lexicographical_compare_kernel.set_arg(0, iterator_size1);
lexicographical_compare_kernel.set_arg(1, iterator_size2);
lexicographical_compare_kernel.set_arg(2, first1.get_buffer());
lexicographical_compare_kernel.set_arg(3, first2.get_buffer());
lexicographical_compare_kernel.set_arg(4, result_vector.get_buffer());
queue.enqueue_1d_range_kernel(lexicographical_compare_kernel,
0,
max_size,
0);
return boost::compute::any_of(result_vector.begin(),
result_vector.end(),
_1 == 0,
queue);
}
} // end detail namespace
/// Checks if the first range [first1, last1) is lexicographically
/// less than the second range [first2, last2).
///
/// Space complexity:
/// \Omega(max(distance(\p first1, \p last1), distance(\p first2, \p last2)))
template
inline bool lexicographical_compare(InputIterator1 first1,
InputIterator1 last1,
InputIterator2 first2,
InputIterator2 last2,
command_queue &queue = system::default_queue())
{
BOOST_STATIC_ASSERT(is_device_iterator::value);
BOOST_STATIC_ASSERT(is_device_iterator::value);
return detail::dispatch_lexicographical_compare(first1, last1, first2, last2, queue);
}
} // end compute namespace
} // end boost namespac