gcc/sparseset.h

   1 /* SparseSet implementation.
   2    Copyright (C) 2007, 2010 Free Software Foundation, Inc.
   3    Contributed by Peter Bergner <bergner@vnet.ibm.com>
   4
   5 This file is part of GCC.
   6
   7 GCC is free software; you can redistribute it and/or modify it under
   8 the terms of the GNU General Public License as published by the Free
   9 Software Foundation; either version 3, or (at your option) any later
  10 version.
  11
  12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  14 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  15 for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GCC; see the file COPYING3.  If not see
  19 <http://www.gnu.org/licenses/>.  */
  20
  21 #ifndef GCC_SPARSESET_H
  22 #define GCC_SPARSESET_H
  23
  24 #define SPARSESET_ELT_BITS ((unsigned) HOST_BITS_PER_WIDEST_FAST_INT)
  25 #define SPARSESET_ELT_TYPE unsigned int
  26
  27 /* Data Structure used for the SparseSet representation.  */
  28
  29 typedef struct sparseset_def
  30 {
  31   SPARSESET_ELT_TYPE *dense;    /* Dense array.  */
  32   SPARSESET_ELT_TYPE *sparse;   /* Sparse array.  */
  33   SPARSESET_ELT_TYPE members;   /* Number of elements.  */
  34   SPARSESET_ELT_TYPE size;      /* Maximum number of elements.  */
  35   SPARSESET_ELT_TYPE iter;      /* Iterator index.  */
  36   unsigned char iter_inc;       /* Iteration increment amount.  */
  37   bool iterating;
  38   SPARSESET_ELT_TYPE elms[2];   /* Combined dense and sparse arrays.  */
  39 } *sparseset;
  40
  41 #define sparseset_free(MAP)  free(MAP)
  42 extern sparseset sparseset_alloc (SPARSESET_ELT_TYPE n_elms);
  43 extern void sparseset_clear_bit (sparseset, SPARSESET_ELT_TYPE);
  44 extern void sparseset_copy (sparseset, sparseset);
  45 extern void sparseset_and (sparseset, sparseset, sparseset);
  46 extern void sparseset_and_compl (sparseset, sparseset, sparseset);
  47 extern void sparseset_ior (sparseset, sparseset, sparseset);
  48 extern bool sparseset_equal_p (sparseset, sparseset);
  49
  50 /* Operation: S = {}
  51    Clear the set of all elements.  */
  52
  53 static inline void
  54 sparseset_clear (sparseset s)
  55 {
  56   s->members = 0;
  57   s->iterating = false;
  58 }
  59
  60 /* Return the number of elements currently in the set.  */
  61
  62 static inline SPARSESET_ELT_TYPE
  63 sparseset_cardinality (sparseset s)
  64 {
  65   return s->members;
  66 }
  67
  68 /* Return the maximum number of elements this set can hold.  */
  69
  70 static inline SPARSESET_ELT_TYPE
  71 sparseset_size (sparseset s)
  72 {
  73   return s->size;
  74 }
  75
  76 /* Return true if e is a member of the set S, otherwise return false.  */
  77
  78 static inline bool
  79 sparseset_bit_p (sparseset s, SPARSESET_ELT_TYPE e)
  80 {
  81   SPARSESET_ELT_TYPE idx;
  82
  83   gcc_assert (e < s->size);
  84
  85   idx = s->sparse[e];
  86
  87   return idx < s->members && s->dense[idx] == e;
  88 }
  89
  90 /* Low level insertion routine not meant for use outside of sparseset.[ch].
  91    Assumes E is valid and not already a member of the set S.  */
  92
  93 static inline void
  94 sparseset_insert_bit (sparseset s, SPARSESET_ELT_TYPE e, SPARSESET_ELT_TYPE idx)
  95 {
  96   s->sparse[e] = idx;
  97   s->dense[idx] = e;
  98 }
  99
 100 /* Operation: S = S + {e}
 101    Insert E into the set S, if it isn't already a member.  */
 102
 103 static inline void
 104 sparseset_set_bit (sparseset s, SPARSESET_ELT_TYPE e)
 105 {
 106   if (!sparseset_bit_p (s, e))
 107     sparseset_insert_bit (s, e, s->members++);
 108 }
 109
 110 /* Return and remove an arbitrary element from the set S.  */
 111
 112 static inline SPARSESET_ELT_TYPE
 113 sparseset_pop (sparseset s)
 114 {
 115   SPARSESET_ELT_TYPE mem = s->members;
 116
 117   gcc_assert (mem != 0);
 118
 119   s->members = mem - 1;
 120   return s->dense[mem];
 121 }
 122
 123 static inline void
 124 sparseset_iter_init (sparseset s)
 125 {
 126   s->iter = 0;
 127   s->iter_inc = 1;
 128   s->iterating = true;
 129 }
 130
 131 static inline bool
 132 sparseset_iter_p (sparseset s)
 133 {
 134   if (s->iterating && s->iter < s->members)
 135     return true;
 136   else
 137     return s->iterating = false;
 138 }
 139
 140 static inline SPARSESET_ELT_TYPE
 141 sparseset_iter_elm (sparseset s)
 142 {
 143   return s->dense[s->iter];
 144 }
 145
 146 static inline void
 147 sparseset_iter_next (sparseset s)
 148 {
 149   s->iter += s->iter_inc;
 150   s->iter_inc = 1;
 151 }
 152
 153 #define EXECUTE_IF_SET_IN_SPARSESET(SPARSESET, ITER)                    \
 154   for (sparseset_iter_init (SPARSESET);                                 \
 155        sparseset_iter_p (SPARSESET)                                     \
 156        && (((ITER) = sparseset_iter_elm (SPARSESET)) || 1);             \
 157        sparseset_iter_next (SPARSESET))
 158
 159 #endif /* GCC_SPARSESET_H */