xref: /dflybsd-src/contrib/gcc-8.0/gcc/et-forest.h (revision 38fd149817dfbff97799f62fcb70be98c4e32523)
1*38fd1498Szrj /* Et-forest data structure implementation.
2*38fd1498Szrj    Copyright (C) 2002-2018 Free Software Foundation, Inc.
3*38fd1498Szrj 
4*38fd1498Szrj    This program is free software; you can redistribute it and/or modify
5*38fd1498Szrj    it under the terms of the GNU General Public License as published by
6*38fd1498Szrj    the Free Software Foundation; either version 3 of the License, or
7*38fd1498Szrj    (at your option) any later version.
8*38fd1498Szrj 
9*38fd1498Szrj    This program is distributed in the hope that it will be useful,
10*38fd1498Szrj    but WITHOUT ANY WARRANTY; without even the implied warranty of
11*38fd1498Szrj    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12*38fd1498Szrj    GNU General Public License for more details.
13*38fd1498Szrj 
14*38fd1498Szrj    You should have received a copy of the GNU General Public License
15*38fd1498Szrj    along with this program; see the file COPYING3.  If not see
16*38fd1498Szrj    <http://www.gnu.org/licenses/>.  */
17*38fd1498Szrj 
18*38fd1498Szrj /* This package implements ET forest data structure. Each tree in
19*38fd1498Szrj    the structure maintains a tree structure and offers logarithmic time
20*38fd1498Szrj    for tree operations (insertion and removal of nodes and edges) and
21*38fd1498Szrj    poly-logarithmic time for nearest common ancestor.
22*38fd1498Szrj 
23*38fd1498Szrj    ET tree stores its structure as a sequence of symbols obtained
24*38fd1498Szrj    by dfs(root)
25*38fd1498Szrj 
26*38fd1498Szrj    dfs (node)
27*38fd1498Szrj    {
28*38fd1498Szrj      s = node;
29*38fd1498Szrj      for each child c of node do
30*38fd1498Szrj        s = concat (s, c, node);
31*38fd1498Szrj      return s;
32*38fd1498Szrj    }
33*38fd1498Szrj 
34*38fd1498Szrj    For example for tree
35*38fd1498Szrj 
36*38fd1498Szrj             1
37*38fd1498Szrj           / | \
38*38fd1498Szrj          2  3  4
39*38fd1498Szrj        / |
40*38fd1498Szrj       4  5
41*38fd1498Szrj 
42*38fd1498Szrj    the sequence is 1 2 4 2 5 3 1 3 1 4 1.
43*38fd1498Szrj 
44*38fd1498Szrj    The sequence is stored in a slightly modified splay tree.
45*38fd1498Szrj    In order to support various types of node values, a hashtable
46*38fd1498Szrj    is used to convert node values to the internal representation.  */
47*38fd1498Szrj 
48*38fd1498Szrj #ifndef _ET_TREE_H
49*38fd1498Szrj #define _ET_TREE_H
50*38fd1498Szrj 
51*38fd1498Szrj #ifdef __cplusplus
52*38fd1498Szrj extern "C" {
53*38fd1498Szrj #endif /* __cplusplus */
54*38fd1498Szrj 
55*38fd1498Szrj /* The node representing the node in an et tree.  */
56*38fd1498Szrj struct et_node
57*38fd1498Szrj {
58*38fd1498Szrj   void *data;			/* The data represented by the node.  */
59*38fd1498Szrj 
60*38fd1498Szrj   int dfs_num_in, dfs_num_out;	/* Number of the node in the dfs ordering.  */
61*38fd1498Szrj 
62*38fd1498Szrj   struct et_node *father;	/* Father of the node.  */
63*38fd1498Szrj   struct et_node *son;		/* The first of the sons of the node.  */
64*38fd1498Szrj   struct et_node *left;
65*38fd1498Szrj   struct et_node *right;	/* The brothers of the node.  */
66*38fd1498Szrj 
67*38fd1498Szrj   struct et_occ *rightmost_occ;	/* The rightmost occurrence.  */
68*38fd1498Szrj   struct et_occ *parent_occ;	/* The occurrence of the parent node.  */
69*38fd1498Szrj };
70*38fd1498Szrj 
71*38fd1498Szrj struct et_node *et_new_tree (void *data);
72*38fd1498Szrj void et_free_tree (struct et_node *);
73*38fd1498Szrj void et_free_tree_force (struct et_node *);
74*38fd1498Szrj void et_free_pools (void);
75*38fd1498Szrj void et_set_father (struct et_node *, struct et_node *);
76*38fd1498Szrj void et_split (struct et_node *);
77*38fd1498Szrj struct et_node *et_nca (struct et_node *, struct et_node *);
78*38fd1498Szrj bool et_below (struct et_node *, struct et_node *);
79*38fd1498Szrj struct et_node *et_root (struct et_node *);
80*38fd1498Szrj 
81*38fd1498Szrj #ifdef __cplusplus
82*38fd1498Szrj }
83*38fd1498Szrj #endif /* __cplusplus */
84*38fd1498Szrj 
85*38fd1498Szrj #endif /* _ET_TREE_H */
86