libstdc++
profiler_algos.h
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1 // -*- C++ -*-
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3 // Copyright (C) 2010 Free Software Foundation, Inc.
4 //
5 // This file is part of the GNU ISO C++ Library. This library is free
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15 
16 // Under Section 7 of GPL version 3, you are granted additional
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18 // 3.1, as published by the Free Software Foundation.
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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 */