1 /* A splay-tree datatype.
2    Copyright 1998, 1999, 2000, 2002, 2005, 2007, 2009, 2010
3    Free Software Foundation, Inc.
4    Contributed by Mark Mitchell (mark@markmitchell.com).
5 
6    This file is part of GCC.
7 
8    GCC is free software; you can redistribute it and/or modify it
9    under the terms of the GNU General Public License as published by
10    the Free Software Foundation; either version 2, or (at your option)
11    any later version.
12 
13    GCC is distributed in the hope that it will be useful, but
14    WITHOUT ANY WARRANTY; without even the implied warranty of
15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
16    General Public License for more details.
17 
18    You should have received a copy of the GNU General Public License
19    along with GCC; see the file COPYING.  If not, write to
20    the Free Software Foundation, 51 Franklin Street - Fifth Floor,
21    Boston, MA 02110-1301, USA.  */
22 
23 /* For an easily readable description of splay-trees, see:
24 
25      Lewis, Harry R. and Denenberg, Larry.  Data Structures and Their
26      Algorithms.  Harper-Collins, Inc.  1991.
27 
28    The major feature of splay trees is that all basic tree operations
29    are amortized O(log n) time for a tree with n nodes.  */
30 
31 #ifndef _SPLAY_TREE_H
32 #define _SPLAY_TREE_H
33 
34 #ifdef __cplusplus
35 extern "C" {
36 #endif /* __cplusplus */
37 
38 #include "ansidecl.h"
39 
40 #ifndef _WIN64
41   typedef unsigned long int libi_uhostptr_t;
42   typedef long int libi_shostptr_t;
43 #else
44 #ifdef __GNUC__
45   __extension__
46 #endif
47   typedef unsigned long long libi_uhostptr_t;
48 #ifdef __GNUC__
49   __extension__
50 #endif
51   typedef long long libi_shostptr_t;
52 #endif
53 
54 #ifndef GTY
55 #define GTY(X)
56 #endif
57 
58 /* Use typedefs for the key and data types to facilitate changing
59    these types, if necessary.  These types should be sufficiently wide
60    that any pointer or scalar can be cast to these types, and then
61    cast back, without loss of precision.  */
62 typedef libi_uhostptr_t splay_tree_key;
63 typedef libi_uhostptr_t splay_tree_value;
64 
65 /* Forward declaration for a node in the tree.  */
66 typedef struct splay_tree_node_s *splay_tree_node;
67 
68 /* The type of a function which compares two splay-tree keys.  The
69    function should return values as for qsort.  */
70 typedef int (*splay_tree_compare_fn) (splay_tree_key, splay_tree_key);
71 
72 /* The type of a function used to deallocate any resources associated
73    with the key.  */
74 typedef void (*splay_tree_delete_key_fn) (splay_tree_key);
75 
76 /* The type of a function used to deallocate any resources associated
77    with the value.  */
78 typedef void (*splay_tree_delete_value_fn) (splay_tree_value);
79 
80 /* The type of a function used to iterate over the tree.  */
81 typedef int (*splay_tree_foreach_fn) (splay_tree_node, void*);
82 
83 /* The type of a function used to allocate memory for tree root and
84    node structures.  The first argument is the number of bytes needed;
85    the second is a data pointer the splay tree functions pass through
86    to the allocator.  This function must never return zero.  */
87 typedef void *(*splay_tree_allocate_fn) (int, void *);
88 
89 /* The type of a function used to free memory allocated using the
90    corresponding splay_tree_allocate_fn.  The first argument is the
91    memory to be freed; the latter is a data pointer the splay tree
92    functions pass through to the freer.  */
93 typedef void (*splay_tree_deallocate_fn) (void *, void *);
94 
95 /* The nodes in the splay tree.  */
96 struct GTY(()) splay_tree_node_s {
97   /* The key.  */
98   splay_tree_key GTY ((use_param1)) key;
99 
100   /* The value.  */
101   splay_tree_value GTY ((use_param2)) value;
102 
103   /* The left and right children, respectively.  */
104   splay_tree_node GTY ((use_params)) left;
105   splay_tree_node GTY ((use_params)) right;
106 };
107 
108 /* The splay tree itself.  */
109 struct GTY(()) splay_tree_s {
110   /* The root of the tree.  */
111   splay_tree_node GTY ((use_params)) root;
112 
113   /* The comparision function.  */
114   splay_tree_compare_fn comp;
115 
116   /* The deallocate-key function.  NULL if no cleanup is necessary.  */
117   splay_tree_delete_key_fn delete_key;
118 
119   /* The deallocate-value function.  NULL if no cleanup is necessary.  */
120   splay_tree_delete_value_fn delete_value;
121 
122   /* Node allocate function.  Takes allocate_data as a parameter. */
123   splay_tree_allocate_fn allocate;
124 
125   /* Free function for nodes and trees.  Takes allocate_data as a parameter.  */
126   splay_tree_deallocate_fn deallocate;
127 
128   /* Parameter for allocate/free functions.  */
129   void * GTY((skip)) allocate_data;
130 };
131 
132 typedef struct splay_tree_s *splay_tree;
133 
134 extern splay_tree splay_tree_new (splay_tree_compare_fn,
135 				  splay_tree_delete_key_fn,
136 				  splay_tree_delete_value_fn);
137 extern splay_tree splay_tree_new_with_allocator (splay_tree_compare_fn,
138 						 splay_tree_delete_key_fn,
139 						 splay_tree_delete_value_fn,
140 						 splay_tree_allocate_fn,
141 						 splay_tree_deallocate_fn,
142 						 void *);
143 extern splay_tree splay_tree_new_typed_alloc (splay_tree_compare_fn,
144 					      splay_tree_delete_key_fn,
145 					      splay_tree_delete_value_fn,
146 					      splay_tree_allocate_fn,
147 					      splay_tree_allocate_fn,
148 					      splay_tree_deallocate_fn,
149 					      void *);
150 extern void splay_tree_delete (splay_tree);
151 extern splay_tree_node splay_tree_insert (splay_tree,
152 					  splay_tree_key,
153 					  splay_tree_value);
154 extern void splay_tree_remove	(splay_tree, splay_tree_key);
155 extern splay_tree_node splay_tree_lookup (splay_tree, splay_tree_key);
156 extern splay_tree_node splay_tree_predecessor (splay_tree, splay_tree_key);
157 extern splay_tree_node splay_tree_successor (splay_tree, splay_tree_key);
158 extern splay_tree_node splay_tree_max (splay_tree);
159 extern splay_tree_node splay_tree_min (splay_tree);
160 extern int splay_tree_foreach (splay_tree, splay_tree_foreach_fn, void*);
161 extern int splay_tree_compare_ints (splay_tree_key, splay_tree_key);
162 extern int splay_tree_compare_pointers (splay_tree_key,	splay_tree_key);
163 
164 #ifdef __cplusplus
165 }
166 #endif /* __cplusplus */
167 
168 #endif /* _SPLAY_TREE_H */
169