libstdc++-v3/include/ext/pb_ds/detail/resize_policy/hash_load_check_resize_trigger_imp.hpp

   1 // -*- C++ -*-
   2
   3 // Copyright (C) 2005-2020 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
  32 // representation about the suitability of this software for any
  33 // purpose. It is provided "as is" without express or implied
  34 // warranty.
  35
  36 /**
  37  * @file hash_load_check_resize_trigger_imp.hpp
  38  * Contains a resize trigger implementation.
  39  */
  40
  41 #ifdef PB_DS_CLASS_C_DEC
  42
  43 #define PB_DS_ASSERT_VALID(X)                                           \
  44   _GLIBCXX_DEBUG_ONLY(X.assert_valid(__FILE__, __LINE__);)
  45
  46 PB_DS_CLASS_T_DEC
  47 PB_DS_CLASS_C_DEC::
  48 hash_load_check_resize_trigger(float load_min, float load_max)
  49 : m_load_min(load_min), m_load_max(load_max), m_next_shrink_size(0),
  50   m_next_grow_size(0), m_resize_needed(false)
  51 { PB_DS_ASSERT_VALID((*this)) }
  52
  53 PB_DS_CLASS_T_DEC
  54 inline void
  55 PB_DS_CLASS_C_DEC::
  56 notify_find_search_start()
  57 { PB_DS_ASSERT_VALID((*this)) }
  58
  59 PB_DS_CLASS_T_DEC
  60 inline void
  61 PB_DS_CLASS_C_DEC::
  62 notify_find_search_collision()
  63 { PB_DS_ASSERT_VALID((*this)) }
  64
  65 PB_DS_CLASS_T_DEC
  66 inline void
  67 PB_DS_CLASS_C_DEC::
  68 notify_find_search_end()
  69 { PB_DS_ASSERT_VALID((*this)) }
  70
  71 PB_DS_CLASS_T_DEC
  72 inline void
  73 PB_DS_CLASS_C_DEC::
  74 notify_insert_search_start()
  75 { PB_DS_ASSERT_VALID((*this)) }
  76
  77 PB_DS_CLASS_T_DEC
  78 inline void
  79 PB_DS_CLASS_C_DEC::
  80 notify_insert_search_collision()
  81 { PB_DS_ASSERT_VALID((*this)) }
  82
  83 PB_DS_CLASS_T_DEC
  84 inline void
  85 PB_DS_CLASS_C_DEC::
  86 notify_insert_search_end()
  87 { PB_DS_ASSERT_VALID((*this)) }
  88
  89 PB_DS_CLASS_T_DEC
  90 inline void
  91 PB_DS_CLASS_C_DEC::
  92 notify_erase_search_start()
  93 { PB_DS_ASSERT_VALID((*this)) }
  94
  95 PB_DS_CLASS_T_DEC
  96 inline void
  97 PB_DS_CLASS_C_DEC::
  98 notify_erase_search_collision()
  99 { PB_DS_ASSERT_VALID((*this)) }
 100
 101 PB_DS_CLASS_T_DEC
 102 inline void
 103 PB_DS_CLASS_C_DEC::
 104 notify_erase_search_end()
 105 { PB_DS_ASSERT_VALID((*this)) }
 106
 107 PB_DS_CLASS_T_DEC
 108 inline void
 109 PB_DS_CLASS_C_DEC::
 110 notify_inserted(size_type num_entries)
 111 {
 112   m_resize_needed = (num_entries >= m_next_grow_size);
 113   size_base::set_size(num_entries);
 114   PB_DS_ASSERT_VALID((*this))
 115 }
 116
 117 PB_DS_CLASS_T_DEC
 118 inline void
 119 PB_DS_CLASS_C_DEC::
 120 notify_erased(size_type num_entries)
 121 {
 122   size_base::set_size(num_entries);
 123   m_resize_needed = num_entries <= m_next_shrink_size;
 124   PB_DS_ASSERT_VALID((*this))
 125 }
 126
 127 PB_DS_CLASS_T_DEC
 128 inline bool
 129 PB_DS_CLASS_C_DEC::
 130 is_resize_needed() const
 131 {
 132   PB_DS_ASSERT_VALID((*this))
 133   return m_resize_needed;
 134 }
 135
 136 PB_DS_CLASS_T_DEC
 137 inline bool
 138 PB_DS_CLASS_C_DEC::
 139 is_grow_needed(size_type /*size*/, size_type num_entries) const
 140 {
 141   _GLIBCXX_DEBUG_ASSERT(m_resize_needed);
 142   return num_entries >= m_next_grow_size;
 143 }
 144
 145 PB_DS_CLASS_T_DEC
 146 PB_DS_CLASS_C_DEC::
 147 ~hash_load_check_resize_trigger() { }
 148
 149 PB_DS_CLASS_T_DEC
 150 void
 151 PB_DS_CLASS_C_DEC::
 152 notify_resized(size_type new_size)
 153 {
 154   m_resize_needed = false;
 155   m_next_grow_size = size_type(m_load_max * new_size - 1);
 156   m_next_shrink_size = size_type(m_load_min * new_size);
 157
 158 #ifdef PB_DS_HT_MAP_RESIZE_TRACE_
 159   std::cerr << "hlcrt::notify_resized "  << std::endl
 160             << "1 " << new_size << std::endl
 161             << "2 " << m_load_min << std::endl
 162             << "3 " << m_load_max << std::endl
 163             << "4 " << m_next_shrink_size << std::endl
 164             << "5 " << m_next_grow_size << std::endl;
 165 #endif
 166
 167   PB_DS_ASSERT_VALID((*this))
 168 }
 169
 170 PB_DS_CLASS_T_DEC
 171 void
 172 PB_DS_CLASS_C_DEC::
 173 notify_externally_resized(size_type new_size)
 174 {
 175   m_resize_needed = false;
 176   size_type new_grow_size = size_type(m_load_max * new_size - 1);
 177   size_type new_shrink_size = size_type(m_load_min * new_size);
 178
 179 #ifdef PB_DS_HT_MAP_RESIZE_TRACE_
 180   std::cerr << "hlcrt::notify_externally_resized "  << std::endl
 181             << "1 " << new_size << std::endl
 182             << "2 " << m_load_min << std::endl
 183             << "3 " << m_load_max << std::endl
 184             << "4 " << m_next_shrink_size << std::endl
 185             << "5 " << m_next_grow_size << std::endl
 186             << "6 " << new_shrink_size << std::endl
 187             << "7 " << new_grow_size << std::endl;
 188 #endif
 189
 190   if (new_grow_size >= m_next_grow_size)
 191     {
 192       _GLIBCXX_DEBUG_ASSERT(new_shrink_size >= m_next_shrink_size);
 193       m_next_grow_size = new_grow_size;
 194     }
 195   else
 196     {
 197       _GLIBCXX_DEBUG_ASSERT(new_shrink_size <= m_next_shrink_size);
 198       m_next_shrink_size = new_shrink_size;
 199     }
 200
 201   PB_DS_ASSERT_VALID((*this))
 202 }
 203
 204 PB_DS_CLASS_T_DEC
 205 void
 206 PB_DS_CLASS_C_DEC::
 207 notify_cleared()
 208 {
 209   PB_DS_ASSERT_VALID((*this))
 210   size_base::set_size(0);
 211   m_resize_needed = (0 < m_next_shrink_size);
 212   PB_DS_ASSERT_VALID((*this))
 213 }
 214
 215 PB_DS_CLASS_T_DEC
 216 void
 217 PB_DS_CLASS_C_DEC::
 218 swap(PB_DS_CLASS_C_DEC& other)
 219 {
 220   PB_DS_ASSERT_VALID((*this))
 221   PB_DS_ASSERT_VALID(other)
 222
 223   size_base::swap(other);
 224   std::swap(m_load_min, other.m_load_min);
 225   std::swap(m_load_max, other.m_load_max);
 226   std::swap(m_resize_needed, other.m_resize_needed);
 227   std::swap(m_next_grow_size, other.m_next_grow_size);
 228   std::swap(m_next_shrink_size, other.m_next_shrink_size);
 229
 230   PB_DS_ASSERT_VALID((*this))
 231   PB_DS_ASSERT_VALID(other)
 232 }
 233
 234 PB_DS_CLASS_T_DEC
 235 inline std::pair<float, float>
 236 PB_DS_CLASS_C_DEC::
 237 get_loads() const
 238 {
 239   PB_DS_STATIC_ASSERT(access, external_load_access);
 240   return std::make_pair(m_load_min, m_load_max);
 241 }
 242
 243 PB_DS_CLASS_T_DEC
 244 void
 245 PB_DS_CLASS_C_DEC::
 246 set_loads(std::pair<float, float> load_pair)
 247 {
 248   PB_DS_STATIC_ASSERT(access, external_load_access);
 249   const float old_load_min = m_load_min;
 250   const float old_load_max = m_load_max;
 251   const size_type old_next_shrink_size = m_next_shrink_size;
 252   const size_type old_next_grow_size = m_next_grow_size;
 253   const bool old_resize_needed = m_resize_needed;
 254
 255   __try
 256     {
 257       m_load_min = load_pair.first;
 258       m_load_max = load_pair.second;
 259       do_resize(static_cast<size_type>(size_base::get_size() / ((m_load_min + m_load_max) / 2)));
 260     }
 261   __catch(...)
 262     {
 263       m_load_min = old_load_min;
 264       m_load_max = old_load_max;
 265       m_next_shrink_size = old_next_shrink_size;
 266       m_next_grow_size = old_next_grow_size;
 267       m_resize_needed = old_resize_needed;
 268       __throw_exception_again;
 269     }
 270 }
 271
 272 PB_DS_CLASS_T_DEC
 273 void
 274 PB_DS_CLASS_C_DEC::
 275 do_resize(size_type)
 276 { std::abort(); }
 277
 278 #ifdef _GLIBCXX_DEBUG
 279 # define PB_DS_DEBUG_VERIFY(_Cond)                                      \
 280   _GLIBCXX_DEBUG_VERIFY_AT(_Cond,                                       \
 281                            _M_message(#_Cond" assertion from %1;:%2;")  \
 282                            ._M_string(__FILE__)._M_integer(__LINE__)    \
 283                            ,__file,__line)
 284
 285 PB_DS_CLASS_T_DEC
 286 void
 287 PB_DS_CLASS_C_DEC::
 288 assert_valid(const char* __file, int __line) const
 289 {
 290   PB_DS_DEBUG_VERIFY(m_load_max > m_load_min);
 291   PB_DS_DEBUG_VERIFY(m_next_grow_size >= m_next_shrink_size);
 292 }
 293 # undef PB_DS_DEBUG_VERIFY
 294 #endif
 295 #undef PB_DS_ASSERT_VALID
 296 #endif