1 // -*- C++ -*-
2 
3 // Copyright (C) 2005-2021 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 splay_tree_/splay_fn_imps.hpp
38  * Contains an implementation class for splay_tree_.
39  */
40 
41 #ifdef PB_DS_CLASS_C_DEC
42 
43 PB_DS_CLASS_T_DEC
44 void
45 PB_DS_CLASS_C_DEC::
splay(node_pointer p_nd)46 splay(node_pointer p_nd)
47 {
48   while (p_nd->m_p_parent != base_type::m_p_head)
49     {
50 #ifdef _GLIBCXX_DEBUG
51       {
52 	node_pointer p_head = base_type::m_p_head;
53 	assert_special_imp(p_head, __FILE__, __LINE__);
54       }
55 #endif
56 
57       PB_DS_ASSERT_BASE_NODE_CONSISTENT(p_nd)
58 
59       if (p_nd->m_p_parent->m_p_parent == base_type::m_p_head)
60 	{
61 	  base_type::rotate_parent(p_nd);
62 	  _GLIBCXX_DEBUG_ASSERT(p_nd == this->m_p_head->m_p_parent);
63 	}
64       else
65 	{
66 	  const node_pointer p_parent = p_nd->m_p_parent;
67 	  const node_pointer p_grandparent = p_parent->m_p_parent;
68 
69 #ifdef _GLIBCXX_DEBUG
70 	  const size_type total =
71 	    base_type::recursive_count(p_grandparent);
72 	  _GLIBCXX_DEBUG_ASSERT(total >= 3);
73 #endif
74 
75 	  if (p_parent->m_p_left == p_nd &&
76 	      p_grandparent->m_p_right == p_parent)
77 	    splay_zig_zag_left(p_nd, p_parent, p_grandparent);
78 	  else if (p_parent->m_p_right == p_nd &&
79 		   p_grandparent->m_p_left == p_parent)
80 	    splay_zig_zag_right(p_nd, p_parent, p_grandparent);
81 	  else if (p_parent->m_p_left == p_nd &&
82 		   p_grandparent->m_p_left == p_parent)
83 	    splay_zig_zig_left(p_nd, p_parent, p_grandparent);
84 	  else
85 	    splay_zig_zig_right(p_nd, p_parent, p_grandparent);
86 	  _GLIBCXX_DEBUG_ASSERT(total ==this->recursive_count(p_nd));
87 	}
88 
89       PB_DS_ASSERT_BASE_NODE_CONSISTENT(p_nd)
90     }
91 }
92 
93 PB_DS_CLASS_T_DEC
94 inline void
95 PB_DS_CLASS_C_DEC::
splay_zig_zag_left(node_pointer p_nd,node_pointer p_parent,node_pointer p_grandparent)96 splay_zig_zag_left(node_pointer p_nd, node_pointer p_parent,
97 		   node_pointer p_grandparent)
98 {
99   _GLIBCXX_DEBUG_ASSERT(p_parent == p_nd->m_p_parent);
100   _GLIBCXX_DEBUG_ASSERT(p_grandparent == p_parent->m_p_parent);
101 
102   PB_DS_ASSERT_BASE_NODE_CONSISTENT(p_grandparent)
103 
104   _GLIBCXX_DEBUG_ASSERT(p_parent->m_p_left == p_nd &&
105 			p_grandparent->m_p_right == p_parent);
106 
107   splay_zz_start(p_nd, p_parent, p_grandparent);
108 
109   node_pointer p_b = p_nd->m_p_right;
110   node_pointer p_c = p_nd->m_p_left;
111 
112   p_nd->m_p_right = p_parent;
113   p_parent->m_p_parent = p_nd;
114 
115   p_nd->m_p_left = p_grandparent;
116   p_grandparent->m_p_parent = p_nd;
117 
118   p_parent->m_p_left = p_b;
119   if (p_b != 0)
120     p_b->m_p_parent = p_parent;
121 
122   p_grandparent->m_p_right = p_c;
123   if (p_c != 0)
124     p_c->m_p_parent = p_grandparent;
125 
126   splay_zz_end(p_nd, p_parent, p_grandparent);
127 }
128 
129 PB_DS_CLASS_T_DEC
130 inline void
131 PB_DS_CLASS_C_DEC::
splay_zig_zag_right(node_pointer p_nd,node_pointer p_parent,node_pointer p_grandparent)132 splay_zig_zag_right(node_pointer p_nd, node_pointer p_parent,
133 		    node_pointer p_grandparent)
134 {
135   _GLIBCXX_DEBUG_ASSERT(p_parent == p_nd->m_p_parent);
136   _GLIBCXX_DEBUG_ASSERT(p_grandparent == p_parent->m_p_parent);
137 
138   PB_DS_ASSERT_BASE_NODE_CONSISTENT(p_grandparent)
139 
140   _GLIBCXX_DEBUG_ASSERT(p_parent->m_p_right == p_nd &&
141 	  		p_grandparent->m_p_left == p_parent);
142 
143   splay_zz_start(p_nd, p_parent, p_grandparent);
144 
145   node_pointer p_b = p_nd->m_p_left;
146   node_pointer p_c = p_nd->m_p_right;
147 
148   p_nd->m_p_left = p_parent;
149   p_parent->m_p_parent = p_nd;
150 
151   p_nd->m_p_right = p_grandparent;
152   p_grandparent->m_p_parent = p_nd;
153 
154   p_parent->m_p_right = p_b;
155   if (p_b != 0)
156     p_b->m_p_parent = p_parent;
157 
158   p_grandparent->m_p_left = p_c;
159   if (p_c != 0)
160     p_c->m_p_parent = p_grandparent;
161 
162   splay_zz_end(p_nd, p_parent, p_grandparent);
163 }
164 
165 PB_DS_CLASS_T_DEC
166 inline void
167 PB_DS_CLASS_C_DEC::
splay_zig_zig_left(node_pointer p_nd,node_pointer p_parent,node_pointer p_grandparent)168 splay_zig_zig_left(node_pointer p_nd, node_pointer p_parent,
169 		   node_pointer p_grandparent)
170 {
171   _GLIBCXX_DEBUG_ASSERT(p_parent == p_nd->m_p_parent);
172   _GLIBCXX_DEBUG_ASSERT(p_grandparent == p_parent->m_p_parent);
173 
174   PB_DS_ASSERT_BASE_NODE_CONSISTENT(p_grandparent)
175 
176   _GLIBCXX_DEBUG_ASSERT(p_parent->m_p_left == p_nd &&
177 		     p_nd->m_p_parent->m_p_parent->m_p_left == p_nd->m_p_parent);
178 
179   splay_zz_start(p_nd, p_parent, p_grandparent);
180 
181   node_pointer p_b = p_nd->m_p_right;
182   node_pointer p_c = p_parent->m_p_right;
183 
184   p_nd->m_p_right = p_parent;
185   p_parent->m_p_parent = p_nd;
186 
187   p_parent->m_p_right = p_grandparent;
188   p_grandparent->m_p_parent = p_parent;
189 
190   p_parent->m_p_left = p_b;
191   if (p_b != 0)
192     p_b->m_p_parent = p_parent;
193 
194   p_grandparent->m_p_left = p_c;
195   if (p_c != 0)
196     p_c->m_p_parent = p_grandparent;
197 
198   splay_zz_end(p_nd, p_parent, p_grandparent);
199 }
200 
201 PB_DS_CLASS_T_DEC
202 inline void
203 PB_DS_CLASS_C_DEC::
splay_zig_zig_right(node_pointer p_nd,node_pointer p_parent,node_pointer p_grandparent)204 splay_zig_zig_right(node_pointer p_nd, node_pointer p_parent,
205 		    node_pointer p_grandparent)
206 {
207   _GLIBCXX_DEBUG_ASSERT(p_parent == p_nd->m_p_parent);
208   _GLIBCXX_DEBUG_ASSERT(p_grandparent == p_parent->m_p_parent);
209   PB_DS_ASSERT_BASE_NODE_CONSISTENT(p_grandparent)
210   _GLIBCXX_DEBUG_ASSERT(p_parent->m_p_right == p_nd &&
211 		  p_nd->m_p_parent->m_p_parent->m_p_right == p_nd->m_p_parent);
212 
213   splay_zz_start(p_nd, p_parent, p_grandparent);
214 
215   node_pointer p_b = p_nd->m_p_left;
216   node_pointer p_c = p_parent->m_p_left;
217 
218   p_nd->m_p_left = p_parent;
219   p_parent->m_p_parent = p_nd;
220 
221   p_parent->m_p_left = p_grandparent;
222   p_grandparent->m_p_parent = p_parent;
223 
224   p_parent->m_p_right = p_b;
225   if (p_b != 0)
226     p_b->m_p_parent = p_parent;
227 
228   p_grandparent->m_p_right = p_c;
229   if (p_c != 0)
230     p_c->m_p_parent = p_grandparent;
231 
232   base_type::update_to_top(p_grandparent, (node_update*)this);
233   splay_zz_end(p_nd, p_parent, p_grandparent);
234 }
235 
236 PB_DS_CLASS_T_DEC
237 inline void
238 PB_DS_CLASS_C_DEC::
splay_zz_start(node_pointer p_nd,node_pointer p_parent,node_pointer p_grandparent)239 splay_zz_start(node_pointer p_nd,
240 #ifdef _GLIBCXX_DEBUG
241 	       node_pointer p_parent,
242 #else
243 	       node_pointer /*p_parent*/,
244 #endif
245 	       node_pointer p_grandparent)
246 {
247   _GLIBCXX_DEBUG_ASSERT(p_nd != 0);
248   _GLIBCXX_DEBUG_ASSERT(p_parent != 0);
249   _GLIBCXX_DEBUG_ASSERT(p_grandparent != 0);
250 
251   const bool grandparent_head = p_grandparent->m_p_parent == base_type::m_p_head;
252 
253   if (grandparent_head)
254     {
255       base_type::m_p_head->m_p_parent = base_type::m_p_head->m_p_parent;
256       p_nd->m_p_parent = base_type::m_p_head;
257       return;
258     }
259 
260   node_pointer p_greatgrandparent = p_grandparent->m_p_parent;
261 
262   p_nd->m_p_parent = p_greatgrandparent;
263 
264   if (p_grandparent == p_greatgrandparent->m_p_left)
265     p_greatgrandparent->m_p_left = p_nd;
266   else
267     p_greatgrandparent->m_p_right = p_nd;
268 }
269 
270 PB_DS_CLASS_T_DEC
271 inline void
272 PB_DS_CLASS_C_DEC::
splay_zz_end(node_pointer p_nd,node_pointer p_parent,node_pointer p_grandparent)273 splay_zz_end(node_pointer p_nd, node_pointer p_parent,
274 	     node_pointer p_grandparent)
275 {
276   if (p_nd->m_p_parent == base_type::m_p_head)
277     base_type::m_p_head->m_p_parent = p_nd;
278 
279   this->apply_update(p_grandparent, (node_update*)this);
280   this->apply_update(p_parent, (node_update*)this);
281   this->apply_update(p_nd, (node_update*)this);
282   PB_DS_ASSERT_BASE_NODE_CONSISTENT(p_nd)
283 }
284 #endif
285