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

   1 // -*- C++ -*-
   2
   3 // Copyright (C) 2005, 2006 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 2, 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 // You should have received a copy of the GNU General Public License
  17 // along with this library; see the file COPYING.  If not, write to
  18 // the Free Software Foundation, 59 Temple Place - Suite 330, Boston,
  19 // MA 02111-1307, USA.
  20
  21 // As a special exception, you may use this file as part of a free
  22 // software library without restriction.  Specifically, if other files
  23 // instantiate templates or use macros or inline functions from this
  24 // file, or you compile this file and link it with other files to
  25 // produce an executable, this file does not by itself cause the
  26 // resulting executable to be covered by the GNU General Public
  27 // License.  This exception does not however invalidate any other
  28 // reasons why the executable file might be covered by the GNU General
  29 // Public License.
  30
  31 // Copyright (C) 2004 Ami Tavory and Vladimir Dreizin, IBM-HRL.
  32
  33 // Permission to use, copy, modify, sell, and distribute this software
  34 // is hereby granted without fee, provided that the above copyright
  35 // notice appears in all copies, and that both that copyright notice
  36 // and this permission notice appear in supporting documentation. None
  37 // of the above authors, nor IBM Haifa Research Laboratories, make any
  38 // representation about the suitability of this software for any
  39 // purpose. It is provided "as is" without express or implied
  40 // warranty.
  41
  42 /**
  43  * @file hash_load_check_resize_trigger_imp.hpp
  44  * Contains a resize trigger implementation.
  45  */
  46
  47 #define PB_DS_STATIC_ASSERT(UNIQUE, E)                                  \
  48   typedef detail::static_assert_dumclass<sizeof(detail::static_assert<(bool)(E)>)> \
  49   UNIQUE##static_assert_type
  50
  51 PB_DS_CLASS_T_DEC
  52 PB_DS_CLASS_C_DEC::
  53 hash_load_check_resize_trigger(float load_min, float load_max) :
  54   m_load_min(load_min),
  55   m_load_max(load_max),
  56   m_next_shrink_size(0),
  57   m_next_grow_size(0),
  58   m_resize_needed(false)
  59 {
  60   PB_DS_DBG_ONLY(assert_valid();)
  61     }
  62
  63 PB_DS_CLASS_T_DEC
  64 inline void
  65 PB_DS_CLASS_C_DEC::
  66 notify_find_search_start()
  67 {
  68   PB_DS_DBG_ONLY(assert_valid();)
  69     }
  70
  71 PB_DS_CLASS_T_DEC
  72 inline void
  73 PB_DS_CLASS_C_DEC::
  74 notify_find_search_collision()
  75 {
  76   PB_DS_DBG_ONLY(assert_valid();)
  77     }
  78
  79 PB_DS_CLASS_T_DEC
  80 inline void
  81 PB_DS_CLASS_C_DEC::
  82 notify_find_search_end()
  83 {
  84   PB_DS_DBG_ONLY(assert_valid();)
  85     }
  86
  87 PB_DS_CLASS_T_DEC
  88 inline void
  89 PB_DS_CLASS_C_DEC::
  90 notify_insert_search_start()
  91 {
  92   PB_DS_DBG_ONLY(assert_valid();)
  93     }
  94
  95 PB_DS_CLASS_T_DEC
  96 inline void
  97 PB_DS_CLASS_C_DEC::
  98 notify_insert_search_collision()
  99 {
 100   PB_DS_DBG_ONLY(assert_valid();)
 101     }
 102
 103 PB_DS_CLASS_T_DEC
 104 inline void
 105 PB_DS_CLASS_C_DEC::
 106 notify_insert_search_end()
 107 {
 108   PB_DS_DBG_ONLY(assert_valid();)
 109     }
 110
 111 PB_DS_CLASS_T_DEC
 112 inline void
 113 PB_DS_CLASS_C_DEC::
 114 notify_erase_search_start()
 115 {
 116   PB_DS_DBG_ONLY(assert_valid();)
 117     }
 118
 119 PB_DS_CLASS_T_DEC
 120 inline void
 121 PB_DS_CLASS_C_DEC::
 122 notify_erase_search_collision()
 123 {
 124   PB_DS_DBG_ONLY(assert_valid();)
 125     }
 126
 127 PB_DS_CLASS_T_DEC
 128 inline void
 129 PB_DS_CLASS_C_DEC::
 130 notify_erase_search_end()
 131 {
 132   PB_DS_DBG_ONLY(assert_valid();)
 133     }
 134
 135 PB_DS_CLASS_T_DEC
 136 inline void
 137 PB_DS_CLASS_C_DEC::
 138 notify_inserted(size_type num_entries)
 139 {
 140   m_resize_needed = (num_entries >= m_next_grow_size);
 141
 142   size_base::set_size(num_entries);
 143
 144   PB_DS_DBG_ONLY(assert_valid();)
 145     }
 146
 147 PB_DS_CLASS_T_DEC
 148 inline void
 149 PB_DS_CLASS_C_DEC::
 150 notify_erased(size_type num_entries)
 151 {
 152   size_base::set_size(num_entries);
 153
 154   m_resize_needed =
 155     num_entries <= m_next_shrink_size;
 156
 157   PB_DS_DBG_ONLY(assert_valid();)
 158     }
 159
 160 PB_DS_CLASS_T_DEC
 161 inline bool
 162 PB_DS_CLASS_C_DEC::
 163 is_resize_needed() const
 164 {
 165   PB_DS_DBG_ONLY(assert_valid();)
 166
 167     return (m_resize_needed);
 168 }
 169
 170 PB_DS_CLASS_T_DEC
 171 inline bool
 172 PB_DS_CLASS_C_DEC::
 173 is_grow_needed(size_type /*size*/, size_type num_entries) const
 174 {
 175   PB_DS_DBG_ASSERT(m_resize_needed);
 176
 177   return (num_entries >= m_next_grow_size);
 178 }
 179
 180 PB_DS_CLASS_T_DEC
 181 PB_DS_CLASS_C_DEC::
 182 ~hash_load_check_resize_trigger()
 183 { }
 184
 185 PB_DS_CLASS_T_DEC
 186 void
 187 PB_DS_CLASS_C_DEC::
 188 notify_resized(size_type new_size)
 189 {
 190   m_resize_needed = false;
 191
 192   m_next_grow_size =
 193     size_type(m_load_max*  new_size - 1);
 194
 195   m_next_shrink_size =
 196     size_type(m_load_min*  new_size);
 197
 198 #ifdef PB_DS_HT_MAP_RESIZE_TRACE_
 199   std::cerr << "hlcrt::notify_resized " <<
 200     static_cast<unsigned long>(new_size) <<    "    " <<
 201     static_cast<unsigned long>(m_load_min) <<    "    " <<
 202     static_cast<unsigned long>(m_load_max) <<    "    " <<
 203     static_cast<unsigned long>(m_next_shrink_size) << " " <<
 204     static_cast<unsigned long>(m_next_grow_size) <<    "    " << std::endl;
 205 #endif // #ifdef PB_DS_HT_MAP_RESIZE_TRACE_
 206
 207   PB_DS_DBG_ONLY(assert_valid();)
 208     }
 209
 210 PB_DS_CLASS_T_DEC
 211 void
 212 PB_DS_CLASS_C_DEC::
 213 notify_externally_resized(size_type new_size)
 214 {
 215   m_resize_needed = false;
 216
 217   size_type new_grow_size =
 218     size_type(m_load_max*  new_size - 1);
 219
 220   size_type new_shrink_size =
 221     size_type(m_load_min*  new_size );
 222
 223   if (new_grow_size >= m_next_grow_size)
 224     {
 225       PB_DS_DBG_ASSERT(new_shrink_size > m_next_shrink_size);
 226
 227       m_next_grow_size = new_grow_size;
 228
 229       PB_DS_DBG_ONLY(assert_valid();)
 230
 231 #ifdef PB_DS_HT_MAP_RESIZE_TRACE_
 232         std::cerr << "hlcrt::notify_externally_resized1 " <<
 233         static_cast<unsigned long>(new_size) <<    "    " <<
 234         static_cast<unsigned long>(m_load_min) <<    "    " <<
 235         static_cast<unsigned long>(m_load_max) <<    "    " <<
 236         static_cast<unsigned long>(m_next_shrink_size) << " " <<
 237         static_cast<unsigned long>(m_next_grow_size) <<    "    " << std::endl;
 238 #endif // #ifdef PB_DS_HT_MAP_RESIZE_TRACE_
 239
 240       return;
 241     }
 242
 243   PB_DS_DBG_ASSERT(new_shrink_size <= m_next_shrink_size);
 244
 245   m_next_shrink_size = new_shrink_size;
 246
 247 #ifdef PB_DS_HT_MAP_RESIZE_TRACE_
 248   std::cerr << "hlcrt::notify_externally_resized2 " <<
 249     static_cast<unsigned long>(new_size) <<    "    " <<
 250     static_cast<unsigned long>(m_load_min) <<    "    " <<
 251     static_cast<unsigned long>(m_load_max) <<    "    " <<
 252     static_cast<unsigned long>(m_next_shrink_size) << " " <<
 253     static_cast<unsigned long>(m_next_grow_size) <<    "    " << std::endl;
 254 #endif // #ifdef PB_DS_HT_MAP_RESIZE_TRACE_
 255
 256   PB_DS_DBG_ONLY(assert_valid();)
 257     }
 258
 259 PB_DS_CLASS_T_DEC
 260 void
 261 PB_DS_CLASS_C_DEC::
 262 notify_cleared()
 263 {
 264   PB_DS_DBG_ONLY(assert_valid();)
 265
 266     size_base::set_size(0);
 267
 268   m_resize_needed = (0 < m_next_shrink_size);
 269
 270   PB_DS_DBG_ONLY(assert_valid();)
 271     }
 272
 273 PB_DS_CLASS_T_DEC
 274 void
 275 PB_DS_CLASS_C_DEC::
 276 swap(PB_DS_CLASS_C_DEC& other)
 277 {
 278   PB_DS_DBG_ONLY(assert_valid();)
 279     PB_DS_DBG_ONLY(other.assert_valid();)
 280
 281     size_base::swap(other);
 282
 283   std::swap(m_load_min, other.m_load_min);
 284   std::swap(m_load_max, other.m_load_max);
 285
 286   std::swap(m_resize_needed, other.m_resize_needed);
 287
 288   std::swap(m_next_grow_size, other.m_next_grow_size);
 289   std::swap(m_next_shrink_size, other.m_next_shrink_size);
 290
 291   PB_DS_DBG_ONLY(assert_valid();)
 292     PB_DS_DBG_ONLY(other.assert_valid();)
 293     }
 294
 295 PB_DS_CLASS_T_DEC
 296 inline std::pair<float, float>
 297 PB_DS_CLASS_C_DEC::
 298 get_loads() const
 299 {
 300   PB_DS_STATIC_ASSERT(access, external_load_access);
 301
 302   return (std::make_pair(m_load_min, m_load_max));
 303 }
 304
 305 PB_DS_CLASS_T_DEC
 306 void
 307 PB_DS_CLASS_C_DEC::
 308 set_loads(std::pair<float, float> load_pair)
 309 {
 310   PB_DS_STATIC_ASSERT(access, external_load_access);
 311
 312   const float old_load_min = m_load_min;
 313   const float old_load_max = m_load_max;
 314   const size_type old_next_shrink_size = m_next_shrink_size;
 315   const size_type old_next_grow_size = m_next_grow_size;
 316   const bool old_resize_needed = m_resize_needed;
 317
 318   try
 319     {
 320       m_load_min = load_pair.first;
 321       m_load_max = load_pair.second;
 322
 323       do_resize(static_cast<size_type>(
 324                                        size_base::get_size() / ((m_load_min + m_load_max) / 2)));
 325     }
 326   catch(...)
 327     {
 328       m_load_min = old_load_min;
 329       m_load_max = old_load_max;
 330       m_next_shrink_size = old_next_shrink_size;
 331       m_next_grow_size = old_next_grow_size;
 332       m_resize_needed = old_resize_needed;
 333
 334       throw;
 335     }
 336 }
 337
 338 PB_DS_CLASS_T_DEC
 339 void
 340 PB_DS_CLASS_C_DEC::
 341 do_resize(size_type /*new_size*/)
 342 {
 343   abort();
 344 }
 345
 346 #ifdef PB_DS_HASH_POLICY_DEBUG
 347 PB_DS_CLASS_T_DEC
 348 void
 349 PB_DS_CLASS_C_DEC::
 350 assert_valid() const
 351 {
 352   PB_DS_DBG_ASSERT(m_load_max > m_load_min);
 353
 354   PB_DS_DBG_ASSERT(m_next_grow_size >= m_next_shrink_size);
 355 }
 356 #endif // #ifdef PB_DS_HASH_POLICY_DEBUG
 357
 358 #undef PB_DS_STATIC_ASSERT
 359