libstdc++

profiler_algos.h
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1 // -*- C++ -*-
2 //
3 // Copyright (C) 2010-2013 Free Software Foundation, Inc.
4 //
5 // This file is part of the GNU ISO C++ Library. This library is free
6 // software; you can redistribute it and/or modify it under the
7 // terms of the GNU General Public License as published by the
8 // Free Software Foundation; either version 3, or (at your option)
9 // any later version.
10 //
11 // This library is distributed in the hope that it will be useful,
12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 // GNU General Public License for more details.
15
16 // Under Section 7 of GPL version 3, you are granted additional
17 // permissions described in the GCC Runtime Library Exception, version
18 // 3.1, as published by the Free Software Foundation.
19
20 // You should have received a copy of the GNU General Public License along
21 // with this library; see the file COPYING3. If not see
22 // <http://www.gnu.org/licenses/>.
23
24 /** @file profile/impl/profiler_algos.h
25 * @brief Algorithms used by the profile extension.
26 *
27 * This file is needed to avoid including <algorithm> or <bits/stl_algo.h>.
28 * Including those files would result in recursive includes.
29 * These implementations are oversimplified. In general, efficiency may be
30 * sacrificed to minimize maintenance overhead.
31 */
32
33 #ifndef _GLIBCXX_PROFILE_PROFILER_ALGOS_H
34 #define _GLIBCXX_PROFILE_PROFILER_ALGOS_H 1
35
36 namespace __gnu_profile
37 {
38 /* Helper for __top_n. Insert in sorted vector, but not beyond Nth elem. */
39 template<typename _Container>
40 void
41 __insert_top_n(_Container& __output,
42 const typename _Container::value_type& __value,
43 typename _Container::size_type __n)
44 {
45 typename _Container::iterator __it = __output.begin();
46 typename _Container::size_type __count = 0;
47
48 // Skip up to N - 1 elements larger than VALUE.
49 // XXX: Could do binary search for random iterators.
50 while (true)
51 {
52 if (__count >= __n)
53 // VALUE is not in top N.
54 return;
55
56 if (__it == __output.end())
57 break;
58
59 if (*__it < __value)
60 break;
61
62 ++__it;
63 ++__count;
64 }
65
66 __output.insert(__it, __value);
67 }
68
69 /* Copy the top N elements in INPUT, sorted in reverse order, to OUTPUT. */
70 template<typename _Container>
71 void
72 __top_n(const _Container& __input, _Container& __output,
73 typename _Container::size_type __n)
74 {
75 __output.clear();
76 typename _Container::const_iterator __it;
77 for (__it = __input.begin(); __it != __input.end(); ++__it)
78 __insert_top_n(__output, *__it, __n);
79 }
80
81 /* Simplified clone of std::for_each. */
82 template<typename _InputIterator, typename _Function>
83 _Function
84 __for_each(_InputIterator __first, _InputIterator __last, _Function __f)
85 {
86 for (; __first != __last; ++__first)
87 __f(*__first);
88 return __f;
89 }
90
91 /* Simplified clone of std::remove. */
92 template<typename _ForwardIterator, typename _Tp>
93 _ForwardIterator
94 __remove(_ForwardIterator __first, _ForwardIterator __last,
95 const _Tp& __value)
96 {
97 if(__first == __last)
98 return __first;
99 _ForwardIterator __result = __first;
100 ++__first;
101 for(; __first != __last; ++__first)
102 if(!(*__first == __value))
103 {
104 *__result = *__first;
105 ++__result;
106 }
107 return __result;
108 }
109 } // namespace __gnu_profile
110
111 #endif /* _GLIBCXX_PROFILE_PROFILER_ALGOS_H */