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-rw-r--r--boost/compute/algorithm/detail/serial_merge.hpp97
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diff --git a/boost/compute/algorithm/detail/serial_merge.hpp b/boost/compute/algorithm/detail/serial_merge.hpp
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+//---------------------------------------------------------------------------//
+// 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_SERIAL_MERGE_HPP
+#define BOOST_COMPUTE_ALGORITHM_SERIAL_MERGE_HPP
+
+#include <iterator>
+
+#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 InputIterator1,
+ class InputIterator2,
+ class OutputIterator,
+ class Compare>
+inline OutputIterator serial_merge(InputIterator1 first1,
+ InputIterator1 last1,
+ InputIterator2 first2,
+ InputIterator2 last2,
+ OutputIterator result,
+ Compare comp,
+ command_queue &queue)
+{
+ typedef typename
+ std::iterator_traits<InputIterator1>::value_type
+ input_type1;
+ typedef typename
+ std::iterator_traits<InputIterator2>::value_type
+ input_type2;
+ typedef typename
+ std::iterator_traits<OutputIterator>::difference_type
+ result_difference_type;
+
+ std::ptrdiff_t size1 = std::distance(first1, last1);
+ std::ptrdiff_t size2 = std::distance(first2, last2);
+
+ meta_kernel k("serial_merge");
+ k.add_set_arg<uint_>("size1", static_cast<uint_>(size1));
+ k.add_set_arg<uint_>("size2", static_cast<uint_>(size2));
+
+ k <<
+ "uint i = 0;\n" << // index in result range
+ "uint j = 0;\n" << // index in first input range
+ "uint k = 0;\n" << // index in second input range
+
+ // fetch initial values from each range
+ k.decl<input_type1>("j_value") << " = " << first1[0] << ";\n" <<
+ k.decl<input_type2>("k_value") << " = " << first2[0] << ";\n" <<
+
+ // merge values from both input ranges to the result range
+ "while(j < size1 && k < size2){\n" <<
+ " if(" << comp(k.var<input_type1>("j_value"),
+ k.var<input_type2>("k_value")) << "){\n" <<
+ " " << result[k.var<uint_>("i++")] << " = j_value;\n" <<
+ " j_value = " << first1[k.var<uint_>("++j")] << ";\n" <<
+ " }\n" <<
+ " else{\n"
+ " " << result[k.var<uint_>("i++")] << " = k_value;\n"
+ " k_value = " << first2[k.var<uint_>("++k")] << ";\n" <<
+ " }\n"
+ "}\n"
+
+ // copy any remaining values from first range
+ "while(j < size1){\n" <<
+ result[k.var<uint_>("i++")] << " = " <<
+ first1[k.var<uint_>("j++")] << ";\n" <<
+ "}\n"
+
+ // copy any remaining values from second range
+ "while(k < size2){\n" <<
+ result[k.var<uint_>("i++")] << " = " <<
+ first2[k.var<uint_>("k++")] << ";\n" <<
+ "}\n";
+
+ // run kernel
+ k.exec(queue);
+
+ return result + static_cast<result_difference_type>(size1 + size2);
+}
+
+} // end detail namespace
+} // end compute namespace
+} // end boost namespace
+
+#endif // BOOST_COMPUTE_ALGORITHM_SERIAL_MERGE_HPP