libstdc++
cc_hash_table_map_/resize_fn_imps.hpp
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1 // -*- C++ -*-
2 
3 // Copyright (C) 2005-2019 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 terms
7 // of the GNU General Public License as published by the Free Software
8 // Foundation; either version 3, or (at your option) any later
9 // version.
10 
11 // This library is distributed in the hope that it will be useful, but
12 // WITHOUT ANY WARRANTY; without even the implied warranty of
13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
14 // 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 and
21 // a copy of the GCC Runtime Library Exception along with this program;
22 // see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
23 // <http://www.gnu.org/licenses/>.
24 
25 // Copyright (C) 2004 Ami Tavory and Vladimir Dreizin, IBM-HRL.
26 
27 // Permission to use, copy, modify, sell, and distribute this software
28 // is hereby granted without fee, provided that the above copyright
29 // notice appears in all copies, and that both that copyright notice
30 // and this permission notice appear in supporting documentation. None
31 // of the above authors, nor IBM Haifa Research Laboratories, make any
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34 // warranty.
35 
36 /**
37  * @file cc_hash_table_map_/resize_fn_imps.hpp
38  * Contains implementations of cc_ht_map_'s resize related functions.
39  */
40 
41 PB_DS_CLASS_T_DEC
42 inline bool
43 PB_DS_CLASS_C_DEC::
44 do_resize_if_needed()
45 {
46  if (!resize_base::is_resize_needed())
47  return false;
48  resize_imp(resize_base::get_new_size(m_num_e, m_num_used_e));
49  return true;
50 }
51 
52 PB_DS_CLASS_T_DEC
53 void
54 PB_DS_CLASS_C_DEC::
55 do_resize(size_type len)
56 { resize_imp(resize_base::get_nearest_larger_size(len)); }
57 
58 PB_DS_CLASS_T_DEC
59 inline void
60 PB_DS_CLASS_C_DEC::
61 do_resize_if_needed_no_throw()
62 {
63  if (!resize_base::is_resize_needed())
64  return;
65 
66  __try
67  {
68  resize_imp(resize_base::get_new_size(m_num_e, m_num_used_e));
69  }
70  __catch(...)
71  { }
72 
73  PB_DS_ASSERT_VALID((*this))
74 }
75 
76 PB_DS_CLASS_T_DEC
77 void
78 PB_DS_CLASS_C_DEC::
79 resize_imp(size_type new_size)
80 {
81  PB_DS_ASSERT_VALID((*this))
82  if (new_size == m_num_e)
83  return;
84 
85  const size_type old_size = m_num_e;
86  entry_pointer_array a_p_entries_resized;
87 
88  // Following line might throw an exception.
89  ranged_hash_fn_base::notify_resized(new_size);
90 
91  __try
92  {
93  // Following line might throw an exception.
94  a_p_entries_resized = s_entry_pointer_allocator.allocate(new_size);
95  m_num_e = new_size;
96  }
97  __catch(...)
98  {
99  ranged_hash_fn_base::notify_resized(old_size);
100  __throw_exception_again;
101  }
102 
103  // At this point no exceptions can be thrown.
104  resize_imp_no_exceptions(new_size, a_p_entries_resized, old_size);
105  Resize_Policy::notify_resized(new_size);
106  PB_DS_ASSERT_VALID((*this))
107 }
108 
109 PB_DS_CLASS_T_DEC
110 void
111 PB_DS_CLASS_C_DEC::
112 resize_imp_no_exceptions(size_type new_size, entry_pointer_array a_p_entries_resized, size_type old_size)
113 {
114  std::fill(a_p_entries_resized, a_p_entries_resized + m_num_e,
115  entry_pointer(0));
116 
117  for (size_type pos = 0; pos < old_size; ++pos)
118  {
119  entry_pointer p_e = m_entries[pos];
120  while (p_e != 0)
121  p_e = resize_imp_no_exceptions_reassign_pointer(p_e, a_p_entries_resized, traits_base::m_store_extra_indicator);
122  }
123 
124  m_num_e = new_size;
125  _GLIBCXX_DEBUG_ONLY(assert_entry_pointer_array_valid(a_p_entries_resized,
126  __FILE__, __LINE__);)
127  s_entry_pointer_allocator.deallocate(m_entries, old_size);
128  m_entries = a_p_entries_resized;
129  PB_DS_ASSERT_VALID((*this))
130 }
131 
134