GCC Middle and Back End API Reference
et-forest.h
Go to the documentation of this file.
1 /* Et-forest data structure implementation.
2  Copyright (C) 2002-2013 Free Software Foundation, Inc.
3 
4  This program is free software; you can redistribute it and/or modify
5  it under the terms of the GNU General Public License as published by
6  the Free Software Foundation; either version 3 of the License, or
7  (at your option) any later version.
8 
9  This program is distributed in the hope that it will be useful,
10  but WITHOUT ANY WARRANTY; without even the implied warranty of
11  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12  GNU General Public License for more details.
13 
14  You should have received a copy of the GNU General Public License
15  along with this program; see the file COPYING3. If not see
16  <http://www.gnu.org/licenses/>. */
17 
18 /* This package implements ET forest data structure. Each tree in
19  the structure maintains a tree structure and offers logarithmic time
20  for tree operations (insertion and removal of nodes and edges) and
21  poly-logarithmic time for nearest common ancestor.
22 
23  ET tree stores its structure as a sequence of symbols obtained
24  by dfs(root)
25 
26  dfs (node)
27  {
28  s = node;
29  for each child c of node do
30  s = concat (s, c, node);
31  return s;
32  }
33 
34  For example for tree
35 
36  1
37  / | \
38  2 3 4
39  / |
40  4 5
41 
42  the sequence is 1 2 4 2 5 3 1 3 1 4 1.
43 
44  The sequence is stored in a slightly modified splay tree.
45  In order to support various types of node values, a hashtable
46  is used to convert node values to the internal representation. */
47 
48 #ifndef _ET_TREE_H
49 #define _ET_TREE_H
50 
51 #ifdef __cplusplus
52 extern "C" {
53 #endif /* __cplusplus */
54 
55 /* The node representing the node in an et tree. */
56 struct et_node
57 {
58  void *data; /* The data represented by the node. */
59 
60  int dfs_num_in, dfs_num_out; /* Number of the node in the dfs ordering. */
61 
62  struct et_node *father; /* Father of the node. */
63  struct et_node *son; /* The first of the sons of the node. */
64  struct et_node *left;
65  struct et_node *right; /* The brothers of the node. */
66 
67  struct et_occ *rightmost_occ; /* The rightmost occurrence. */
68  struct et_occ *parent_occ; /* The occurrence of the parent node. */
69 };
70 
71 struct et_node *et_new_tree (void *data);
72 void et_free_tree (struct et_node *);
73 void et_free_tree_force (struct et_node *);
74 void et_free_pools (void);
75 void et_set_father (struct et_node *, struct et_node *);
76 void et_split (struct et_node *);
77 struct et_node *et_nca (struct et_node *, struct et_node *);
78 bool et_below (struct et_node *, struct et_node *);
79 struct et_node *et_root (struct et_node *);
80 
81 #ifdef __cplusplus
82 }
83 #endif /* __cplusplus */
84 
85 #endif /* _ET_TREE_H */