contrib/gcc-8.0/libstdc++-v3/include/ext/pb_ds/detail/pat_trie_/split_fn_imps.hpp

   1 // -*- C++ -*-
   2
   3 // Copyright (C) 2005-2018 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 pat_trie_/split_fn_imps.hpp
  38  * Contains an implementation class for pat_trie.
  39  */
  40
  41 PB_DS_CLASS_T_DEC
  42 void
  43 PB_DS_CLASS_C_DEC::
  44 split(key_const_reference r_key, PB_DS_CLASS_C_DEC& other)
  45 {
  46   PB_DS_ASSERT_VALID((*this))
  47   PB_DS_ASSERT_VALID(other)
  48   branch_bag bag;
  49   leaf_pointer p_split_lf = split_prep(r_key, other, bag);
  50   if (p_split_lf == 0)
  51     {
  52       _GLIBCXX_DEBUG_ASSERT(bag.empty());
  53       PB_DS_ASSERT_VALID((*this))
  54       PB_DS_ASSERT_VALID(other)
  55       return;
  56     }
  57
  58   _GLIBCXX_DEBUG_ASSERT(!bag.empty());
  59   other.clear();
  60
  61   m_p_head->m_p_parent = rec_split(m_p_head->m_p_parent, pref_begin(p_split_lf),
  62                                    pref_end(p_split_lf), other, bag);
  63
  64   m_p_head->m_p_parent->m_p_parent = m_p_head;
  65
  66   head_pointer __ohead = other.m_p_head;
  67   __ohead->m_p_max = m_p_head->m_p_max;
  68   m_p_head->m_p_max = rightmost_descendant(m_p_head->m_p_parent);
  69   __ohead->m_p_min = other.leftmost_descendant(__ohead->m_p_parent);
  70
  71   other.m_size = std::distance(other.PB_DS_CLASS_C_DEC::begin(),
  72                                other.PB_DS_CLASS_C_DEC::end());
  73   m_size -= other.m_size;
  74   PB_DS_ASSERT_VALID((*this))
  75   PB_DS_ASSERT_VALID(other)
  76 }
  77
  78 PB_DS_CLASS_T_DEC
  79 typename PB_DS_CLASS_C_DEC::leaf_pointer
  80 PB_DS_CLASS_C_DEC::
  81 split_prep(key_const_reference r_key, PB_DS_CLASS_C_DEC& other,
  82            branch_bag& r_bag)
  83 {
  84   _GLIBCXX_DEBUG_ASSERT(r_bag.empty());
  85   if (m_size == 0)
  86     {
  87       other.clear();
  88       PB_DS_ASSERT_VALID((*this))
  89       PB_DS_ASSERT_VALID(other)
  90       return 0;
  91     }
  92
  93   if (synth_access_traits::cmp_keys(r_key,
  94                                     PB_DS_V2F(static_cast<leaf_const_pointer>(m_p_head->m_p_min)->value())))
  95     {
  96       other.clear();
  97       value_swap(other);
  98       PB_DS_ASSERT_VALID((*this))
  99       PB_DS_ASSERT_VALID(other)
 100       return 0;
 101     }
 102
 103   if (!synth_access_traits::cmp_keys(r_key,
 104                                        PB_DS_V2F(static_cast<leaf_const_pointer>(m_p_head->m_p_max)->value())))
 105     {
 106       PB_DS_ASSERT_VALID((*this))
 107       PB_DS_ASSERT_VALID(other)
 108       return 0;
 109     }
 110
 111   iterator it = lower_bound(r_key);
 112
 113   if (!synth_access_traits::equal_keys(PB_DS_V2F(*it), r_key))
 114     --it;
 115
 116   node_pointer p_nd = it.m_p_nd;
 117   _GLIBCXX_DEBUG_ASSERT(p_nd->m_type == leaf_node);
 118   leaf_pointer p_ret_l = static_cast<leaf_pointer>(p_nd);
 119   while (p_nd->m_type != head_node)
 120     {
 121       r_bag.add_branch();
 122       p_nd = p_nd->m_p_parent;
 123     }
 124   _GLIBCXX_DEBUG_ONLY(debug_base::split(r_key,(synth_access_traits&)(*this), other);)
 125
 126   return p_ret_l;
 127 }
 128
 129 PB_DS_CLASS_T_DEC
 130 typename PB_DS_CLASS_C_DEC::node_pointer
 131 PB_DS_CLASS_C_DEC::
 132 rec_split(node_pointer p_nd, a_const_iterator b_it, a_const_iterator e_it,
 133           PB_DS_CLASS_C_DEC& other, branch_bag& r_bag)
 134 {
 135   if (p_nd->m_type == leaf_node)
 136     {
 137       _GLIBCXX_DEBUG_ASSERT(other.m_p_head->m_p_parent == 0);
 138       return p_nd;
 139     }
 140
 141   _GLIBCXX_DEBUG_ASSERT(p_nd->m_type == i_node);
 142   inode_pointer p_ind = static_cast<inode_pointer>(p_nd);
 143
 144   node_pointer pfirst = p_ind->get_child_node(b_it, e_it, this);
 145   node_pointer p_child_ret = rec_split(pfirst, b_it, e_it, other, r_bag);
 146   PB_DS_ASSERT_NODE_VALID(p_child_ret)
 147   p_ind->replace_child(p_child_ret, b_it, e_it, this);
 148   apply_update(p_ind, (node_update*)this);
 149
 150   inode_iterator child_it = p_ind->get_child_it(b_it, e_it, this);
 151   const size_type lhs_dist = std::distance(p_ind->begin(), child_it);
 152   const size_type lhs_num_children = lhs_dist + 1;
 153   _GLIBCXX_DEBUG_ASSERT(lhs_num_children > 0);
 154
 155   const size_type rhs_dist =  std::distance(p_ind->begin(), p_ind->end());
 156   size_type rhs_num_children = rhs_dist - lhs_num_children;
 157   if (rhs_num_children == 0)
 158     {
 159       apply_update(p_ind, (node_update*)this);
 160       return p_ind;
 161     }
 162
 163   other.split_insert_branch(p_ind->get_e_ind(), b_it, child_it,
 164                             rhs_num_children, r_bag);
 165
 166   child_it = p_ind->get_child_it(b_it, e_it, this);
 167   while (rhs_num_children != 0)
 168     {
 169       ++child_it;
 170       p_ind->remove_child(child_it);
 171       --rhs_num_children;
 172     }
 173   apply_update(p_ind, (node_update*)this);
 174
 175   const size_type int_dist = std::distance(p_ind->begin(), p_ind->end());
 176   _GLIBCXX_DEBUG_ASSERT(int_dist >= 1);
 177   if (int_dist > 1)
 178     {
 179       p_ind->update_prefixes(this);
 180       PB_DS_ASSERT_NODE_VALID(p_ind)
 181       apply_update(p_ind, (node_update*)this);
 182       return p_ind;
 183     }
 184
 185   node_pointer p_ret = *p_ind->begin();
 186   p_ind->~inode();
 187   s_inode_allocator.deallocate(p_ind, 1);
 188   apply_update(p_ret, (node_update*)this);
 189   return p_ret;
 190 }
 191
 192 PB_DS_CLASS_T_DEC
 193 void
 194 PB_DS_CLASS_C_DEC::
 195 split_insert_branch(size_type e_ind, a_const_iterator b_it,
 196                     inode_iterator child_b_it,
 197                     size_type num_children, branch_bag& r_bag)
 198 {
 199 #ifdef _GLIBCXX_DEBUG
 200   if (m_p_head->m_p_parent != 0)
 201     PB_DS_ASSERT_NODE_VALID(m_p_head->m_p_parent)
 202 #endif
 203
 204   const size_type start = m_p_head->m_p_parent == 0 ? 0 : 1;
 205   const size_type total_num_children = start + num_children;
 206   if (total_num_children == 0)
 207     {
 208       _GLIBCXX_DEBUG_ASSERT(m_p_head->m_p_parent == 0);
 209       return;
 210     }
 211
 212   if (total_num_children == 1)
 213     {
 214       if (m_p_head->m_p_parent != 0)
 215         {
 216           PB_DS_ASSERT_NODE_VALID(m_p_head->m_p_parent)
 217           return;
 218         }
 219
 220       _GLIBCXX_DEBUG_ASSERT(m_p_head->m_p_parent == 0);
 221       ++child_b_it;
 222       m_p_head->m_p_parent = *child_b_it;
 223       m_p_head->m_p_parent->m_p_parent = m_p_head;
 224       apply_update(m_p_head->m_p_parent, (node_update*)this);
 225       PB_DS_ASSERT_NODE_VALID(m_p_head->m_p_parent)
 226       return;
 227     }
 228
 229   _GLIBCXX_DEBUG_ASSERT(total_num_children > 1);
 230   inode_pointer p_new_root = r_bag.get_branch();
 231   new (p_new_root) inode(e_ind, b_it);
 232   size_type num_inserted = 0;
 233   while (num_inserted++ < num_children)
 234     {
 235       ++child_b_it;
 236       PB_DS_ASSERT_NODE_VALID((*child_b_it))
 237       p_new_root->add_child(*child_b_it, pref_begin(*child_b_it),
 238                             pref_end(*child_b_it), this);
 239     }
 240
 241   if (m_p_head->m_p_parent != 0)
 242     p_new_root->add_child(m_p_head->m_p_parent,
 243                           pref_begin(m_p_head->m_p_parent),
 244                           pref_end(m_p_head->m_p_parent), this);
 245
 246   m_p_head->m_p_parent = p_new_root;
 247   p_new_root->m_p_parent = m_p_head;
 248   apply_update(m_p_head->m_p_parent, (node_update*)this);
 249   PB_DS_ASSERT_NODE_VALID(m_p_head->m_p_parent)
 250 }