include/splay-tree.h

   1 /* A splay-tree datatype.
   2    Copyright (C) 1998-2015 Free Software Foundation, Inc.
   3    Contributed by Mark Mitchell (mark@markmitchell.com).
   4
   5    This file is part of GCC.
   6
   7    GCC is free software; you can redistribute it and/or modify it
   8    under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 2, or (at your option)
  10    any later version.
  11
  12    GCC is distributed in the hope that it will be useful, but
  13    WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15    General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with GCC; see the file COPYING.  If not, write to
  19    the Free Software Foundation, 51 Franklin Street - Fifth Floor,
  20    Boston, MA 02110-1301, USA.  */
  21
  22 /* For an easily readable description of splay-trees, see:
  23
  24      Lewis, Harry R. and Denenberg, Larry.  Data Structures and Their
  25      Algorithms.  Harper-Collins, Inc.  1991.
  26
  27    The major feature of splay trees is that all basic tree operations
  28    are amortized O(log n) time for a tree with n nodes.  */
  29
  30 #ifndef _SPLAY_TREE_H
  31 #define _SPLAY_TREE_H
  32
  33 #ifdef __cplusplus
  34 extern "C" {
  35 #endif /* __cplusplus */
  36
  37 #include "ansidecl.h"
  38
  39 #ifdef HAVE_STDINT_H
  40 #include <stdint.h>
  41 #endif
  42 #ifdef HAVE_INTTYPES_H
  43 #include <inttypes.h>
  44 #endif
  45
  46 #ifndef GTY
  47 #define GTY(X)
  48 #endif
  49
  50 /* Use typedefs for the key and data types to facilitate changing
  51    these types, if necessary.  These types should be sufficiently wide
  52    that any pointer or scalar can be cast to these types, and then
  53    cast back, without loss of precision.  */
  54 typedef uintptr_t splay_tree_key;
  55 typedef uintptr_t splay_tree_value;
  56
  57 /* Forward declaration for a node in the tree.  */
  58 typedef struct splay_tree_node_s *splay_tree_node;
  59
  60 /* The type of a function which compares two splay-tree keys.  The
  61    function should return values as for qsort.  */
  62 typedef int (*splay_tree_compare_fn) (splay_tree_key, splay_tree_key);
  63
  64 /* The type of a function used to deallocate any resources associated
  65    with the key.  */
  66 typedef void (*splay_tree_delete_key_fn) (splay_tree_key);
  67
  68 /* The type of a function used to deallocate any resources associated
  69    with the value.  */
  70 typedef void (*splay_tree_delete_value_fn) (splay_tree_value);
  71
  72 /* The type of a function used to iterate over the tree.  */
  73 typedef int (*splay_tree_foreach_fn) (splay_tree_node, void*);
  74
  75 /* The type of a function used to allocate memory for tree root and
  76    node structures.  The first argument is the number of bytes needed;
  77    the second is a data pointer the splay tree functions pass through
  78    to the allocator.  This function must never return zero.  */
  79 typedef void *(*splay_tree_allocate_fn) (int, void *);
  80
  81 /* The type of a function used to free memory allocated using the
  82    corresponding splay_tree_allocate_fn.  The first argument is the
  83    memory to be freed; the latter is a data pointer the splay tree
  84    functions pass through to the freer.  */
  85 typedef void (*splay_tree_deallocate_fn) (void *, void *);
  86
  87 /* The nodes in the splay tree.  */
  88 struct GTY(()) splay_tree_node_s {
  89   /* The key.  */
  90   splay_tree_key GTY ((use_param1)) key;
  91
  92   /* The value.  */
  93   splay_tree_value GTY ((use_param2)) value;
  94
  95   /* The left and right children, respectively.  */
  96   splay_tree_node GTY ((use_params)) left;
  97   splay_tree_node GTY ((use_params)) right;
  98 };
  99
 100 /* The splay tree itself.  */
 101 struct GTY(()) splay_tree_s {
 102   /* The root of the tree.  */
 103   splay_tree_node GTY ((use_params)) root;
 104
 105   /* The comparision function.  */
 106   splay_tree_compare_fn comp;
 107
 108   /* The deallocate-key function.  NULL if no cleanup is necessary.  */
 109   splay_tree_delete_key_fn delete_key;
 110
 111   /* The deallocate-value function.  NULL if no cleanup is necessary.  */
 112   splay_tree_delete_value_fn delete_value;
 113
 114   /* Node allocate function.  Takes allocate_data as a parameter. */
 115   splay_tree_allocate_fn allocate;
 116
 117   /* Free function for nodes and trees.  Takes allocate_data as a parameter.  */
 118   splay_tree_deallocate_fn deallocate;
 119
 120   /* Parameter for allocate/free functions.  */
 121   void * GTY((skip)) allocate_data;
 122 };
 123
 124 typedef struct splay_tree_s *splay_tree;
 125
 126 extern splay_tree splay_tree_new (splay_tree_compare_fn,
 127                                   splay_tree_delete_key_fn,
 128                                   splay_tree_delete_value_fn);
 129 extern splay_tree splay_tree_new_with_allocator (splay_tree_compare_fn,
 130                                                  splay_tree_delete_key_fn,
 131                                                  splay_tree_delete_value_fn,
 132                                                  splay_tree_allocate_fn,
 133                                                  splay_tree_deallocate_fn,
 134                                                  void *);
 135 extern splay_tree splay_tree_new_typed_alloc (splay_tree_compare_fn,
 136                                               splay_tree_delete_key_fn,
 137                                               splay_tree_delete_value_fn,
 138                                               splay_tree_allocate_fn,
 139                                               splay_tree_allocate_fn,
 140                                               splay_tree_deallocate_fn,
 141                                               void *);
 142 extern void splay_tree_delete (splay_tree);
 143 extern splay_tree_node splay_tree_insert (splay_tree,
 144                                           splay_tree_key,
 145                                           splay_tree_value);
 146 extern void splay_tree_remove   (splay_tree, splay_tree_key);
 147 extern splay_tree_node splay_tree_lookup (splay_tree, splay_tree_key);
 148 extern splay_tree_node splay_tree_predecessor (splay_tree, splay_tree_key);
 149 extern splay_tree_node splay_tree_successor (splay_tree, splay_tree_key);
 150 extern splay_tree_node splay_tree_max (splay_tree);
 151 extern splay_tree_node splay_tree_min (splay_tree);
 152 extern int splay_tree_foreach (splay_tree, splay_tree_foreach_fn, void*);
 153 extern int splay_tree_compare_ints (splay_tree_key, splay_tree_key);
 154 extern int splay_tree_compare_pointers (splay_tree_key, splay_tree_key);
 155
 156 #ifdef __cplusplus
 157 }
 158 #endif /* __cplusplus */
 159
 160 #endif /* _SPLAY_TREE_H */