1 //---------------------------------------------------------------------------//
2 // Copyright (c) 2013 Kyle Lutz <kyle.r.lutz@gmail.com>
3 //
4 // Distributed under the Boost Software License, Version 1.0
5 // See accompanying file LICENSE_1_0.txt or copy at
6 // http://www.boost.org/LICENSE_1_0.txt
7 //
8 // See http://boostorg.github.com/compute for more information.
9 //---------------------------------------------------------------------------//
10
11 #ifndef BOOST_COMPUTE_ALGORITHM_DETAIL_INSERTION_SORT_HPP
12 #define BOOST_COMPUTE_ALGORITHM_DETAIL_INSERTION_SORT_HPP
13
14 #include <boost/compute/kernel.hpp>
15 #include <boost/compute/program.hpp>
16 #include <boost/compute/command_queue.hpp>
17 #include <boost/compute/detail/meta_kernel.hpp>
18 #include <boost/compute/detail/iterator_range_size.hpp>
19 #include <boost/compute/memory/local_buffer.hpp>
20
21 namespace boost {
22 namespace compute {
23 namespace detail {
24
25 template<class Iterator, class Compare>
serial_insertion_sort(Iterator first,Iterator last,Compare compare,command_queue & queue)26 inline void serial_insertion_sort(Iterator first,
27 Iterator last,
28 Compare compare,
29 command_queue &queue)
30 {
31 typedef typename std::iterator_traits<Iterator>::value_type T;
32
33 size_t count = iterator_range_size(first, last);
34 if(count < 2){
35 return;
36 }
37
38 meta_kernel k("serial_insertion_sort");
39 size_t local_data_arg = k.add_arg<T *>(memory_object::local_memory, "data");
40 size_t count_arg = k.add_arg<uint_>("n");
41
42 k <<
43 // copy data to local memory
44 "for(uint i = 0; i < n; i++){\n" <<
45 " data[i] = " << first[k.var<uint_>("i")] << ";\n"
46 "}\n"
47
48 // sort data in local memory
49 "for(uint i = 1; i < n; i++){\n" <<
50 " " << k.decl<const T>("value") << " = data[i];\n" <<
51 " uint pos = i;\n" <<
52 " while(pos > 0 && " <<
53 compare(k.var<const T>("value"),
54 k.var<const T>("data[pos-1]")) << "){\n" <<
55 " data[pos] = data[pos-1];\n" <<
56 " pos--;\n" <<
57 " }\n" <<
58 " data[pos] = value;\n" <<
59 "}\n" <<
60
61 // copy sorted data to output
62 "for(uint i = 0; i < n; i++){\n" <<
63 " " << first[k.var<uint_>("i")] << " = data[i];\n"
64 "}\n";
65
66 const context &context = queue.get_context();
67 ::boost::compute::kernel kernel = k.compile(context);
68 kernel.set_arg(local_data_arg, local_buffer<T>(count));
69 kernel.set_arg(count_arg, static_cast<uint_>(count));
70
71 queue.enqueue_task(kernel);
72 }
73
74 template<class Iterator>
serial_insertion_sort(Iterator first,Iterator last,command_queue & queue)75 inline void serial_insertion_sort(Iterator first,
76 Iterator last,
77 command_queue &queue)
78 {
79 typedef typename std::iterator_traits<Iterator>::value_type T;
80
81 ::boost::compute::less<T> less;
82
83 return serial_insertion_sort(first, last, less, queue);
84 }
85
86 template<class KeyIterator, class ValueIterator, class Compare>
serial_insertion_sort_by_key(KeyIterator keys_first,KeyIterator keys_last,ValueIterator values_first,Compare compare,command_queue & queue)87 inline void serial_insertion_sort_by_key(KeyIterator keys_first,
88 KeyIterator keys_last,
89 ValueIterator values_first,
90 Compare compare,
91 command_queue &queue)
92 {
93 typedef typename std::iterator_traits<KeyIterator>::value_type key_type;
94 typedef typename std::iterator_traits<ValueIterator>::value_type value_type;
95
96 size_t count = iterator_range_size(keys_first, keys_last);
97 if(count < 2){
98 return;
99 }
100
101 meta_kernel k("serial_insertion_sort_by_key");
102 size_t local_keys_arg = k.add_arg<key_type *>(memory_object::local_memory, "keys");
103 size_t local_data_arg = k.add_arg<value_type *>(memory_object::local_memory, "data");
104 size_t count_arg = k.add_arg<uint_>("n");
105
106 k <<
107 // copy data to local memory
108 "for(uint i = 0; i < n; i++){\n" <<
109 " keys[i] = " << keys_first[k.var<uint_>("i")] << ";\n"
110 " data[i] = " << values_first[k.var<uint_>("i")] << ";\n"
111 "}\n"
112
113 // sort data in local memory
114 "for(uint i = 1; i < n; i++){\n" <<
115 " " << k.decl<const key_type>("key") << " = keys[i];\n" <<
116 " " << k.decl<const value_type>("value") << " = data[i];\n" <<
117 " uint pos = i;\n" <<
118 " while(pos > 0 && " <<
119 compare(k.var<const key_type>("key"),
120 k.var<const key_type>("keys[pos-1]")) << "){\n" <<
121 " keys[pos] = keys[pos-1];\n" <<
122 " data[pos] = data[pos-1];\n" <<
123 " pos--;\n" <<
124 " }\n" <<
125 " keys[pos] = key;\n" <<
126 " data[pos] = value;\n" <<
127 "}\n" <<
128
129 // copy sorted data to output
130 "for(uint i = 0; i < n; i++){\n" <<
131 " " << keys_first[k.var<uint_>("i")] << " = keys[i];\n"
132 " " << values_first[k.var<uint_>("i")] << " = data[i];\n"
133 "}\n";
134
135 const context &context = queue.get_context();
136 ::boost::compute::kernel kernel = k.compile(context);
137 kernel.set_arg(local_keys_arg, static_cast<uint_>(count * sizeof(key_type)), 0);
138 kernel.set_arg(local_data_arg, static_cast<uint_>(count * sizeof(value_type)), 0);
139 kernel.set_arg(count_arg, static_cast<uint_>(count));
140
141 queue.enqueue_task(kernel);
142 }
143
144 template<class KeyIterator, class ValueIterator>
serial_insertion_sort_by_key(KeyIterator keys_first,KeyIterator keys_last,ValueIterator values_first,command_queue & queue)145 inline void serial_insertion_sort_by_key(KeyIterator keys_first,
146 KeyIterator keys_last,
147 ValueIterator values_first,
148 command_queue &queue)
149 {
150 typedef typename std::iterator_traits<KeyIterator>::value_type key_type;
151
152 serial_insertion_sort_by_key(
153 keys_first,
154 keys_last,
155 values_first,
156 boost::compute::less<key_type>(),
157 queue
158 );
159 }
160
161 } // end detail namespace
162 } // end compute namespace
163 } // end boost namespace
164
165 #endif // BOOST_COMPUTE_ALGORITHM_DETAIL_INSERTION_SORT_HPP
166