gcc/sparseset.h

   1 /* SparseSet implementation.
   2    Copyright (C) 2007 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 #include "system.h"
  25 #include <assert.h>
  26
  27 #define SPARSESET_ELT_BITS ((unsigned) HOST_BITS_PER_WIDEST_FAST_INT)
  28 #define SPARSESET_ELT_TYPE unsigned int
  29
  30 /* Data Structure used for the SparseSet representation.  */
  31
  32 typedef struct sparseset_def
  33 {
  34   SPARSESET_ELT_TYPE *dense;    /* Dense array.  */
  35   SPARSESET_ELT_TYPE *sparse;   /* Sparse array.  */
  36   SPARSESET_ELT_TYPE members;   /* Number of elements.  */
  37   SPARSESET_ELT_TYPE size;      /* Maximum number of elements.  */
  38   SPARSESET_ELT_TYPE iter;      /* Iterator index.  */
  39   unsigned char iter_inc;       /* Iteration increment amount.  */
  40   bool iterating;
  41   SPARSESET_ELT_TYPE elms[2];   /* Combined dense and sparse arrays.  */
  42 } *sparseset;
  43
  44 #define sparseset_free(MAP)  free(MAP)
  45 extern sparseset sparseset_alloc (SPARSESET_ELT_TYPE n_elms);
  46 extern void sparseset_clear_bit (sparseset, SPARSESET_ELT_TYPE);
  47 extern void sparseset_copy (sparseset, sparseset);
  48 extern void sparseset_and (sparseset, sparseset, sparseset);
  49 extern void sparseset_and_compl (sparseset, sparseset, sparseset);
  50 extern void sparseset_ior (sparseset, sparseset, sparseset);
  51 extern bool sparseset_equal_p (sparseset, sparseset);
  52
  53 /* Operation: S = {}
  54    Clear the set of all elements.  */
  55
  56 static inline void
  57 sparseset_clear (sparseset s)
  58 {
  59   s->members = 0;
  60   s->iterating = false;
  61 }
  62
  63 /* Return the number of elements currently in the set.  */
  64
  65 static inline SPARSESET_ELT_TYPE
  66 sparseset_cardinality (sparseset s)
  67 {
  68   return s->members;
  69 }
  70
  71 /* Return the maximum number of elements this set can hold.  */
  72
  73 static inline SPARSESET_ELT_TYPE
  74 sparseset_size (sparseset s)
  75 {
  76   return s->size;
  77 }
  78
  79 /* Return true if e is a member of the set S, otherwise return false.  */
  80
  81 static inline bool
  82 sparseset_bit_p (sparseset s, SPARSESET_ELT_TYPE e)
  83 {
  84   SPARSESET_ELT_TYPE idx;
  85
  86   gcc_assert (e < s->size);
  87
  88   idx = s->sparse[e];
  89
  90   return idx < s->members && s->dense[idx] == e;
  91 }
  92
  93 /* Low level insertion routine not meant for use outside of sparseset.[ch].
  94    Assumes E is valid and not already a member of the set S.  */
  95
  96 static inline void
  97 sparseset_insert_bit (sparseset s, SPARSESET_ELT_TYPE e, SPARSESET_ELT_TYPE idx)
  98 {
  99   s->sparse[e] = idx;
 100   s->dense[idx] = e;
 101 }
 102
 103 /* Operation: S = S + {e}
 104    Insert E into the set S, if it isn't already a member.  */
 105
 106 static inline void
 107 sparseset_set_bit (sparseset s, SPARSESET_ELT_TYPE e)
 108 {
 109   if (!sparseset_bit_p (s, e))
 110     sparseset_insert_bit (s, e, s->members++);
 111 }
 112
 113 /* Return and remove an arbitrary element from the set S.  */
 114
 115 static inline SPARSESET_ELT_TYPE
 116 sparseset_pop (sparseset s)
 117 {
 118   SPARSESET_ELT_TYPE mem = s->members;
 119
 120   gcc_assert (mem != 0);
 121
 122   s->members = mem - 1;
 123   return s->dense[mem];
 124 }
 125
 126 static inline void
 127 sparseset_iter_init (sparseset s)
 128 {
 129   s->iter = 0;
 130   s->iter_inc = 1;
 131   s->iterating = true;
 132 }
 133
 134 static inline bool
 135 sparseset_iter_p (sparseset s)
 136 {
 137   if (s->iterating && s->iter < s->members)
 138     return true;
 139   else
 140     return s->iterating = false;
 141 }
 142
 143 static inline SPARSESET_ELT_TYPE
 144 sparseset_iter_elm (sparseset s)
 145 {
 146   return s->dense[s->iter];
 147 }
 148
 149 static inline void
 150 sparseset_iter_next (sparseset s)
 151 {
 152   s->iter += s->iter_inc;
 153   s->iter_inc = 1;
 154 }
 155
 156 #define EXECUTE_IF_SET_IN_SPARSESET(SPARSESET, ITER)                    \
 157   for (sparseset_iter_init (SPARSESET);                                 \
 158        sparseset_iter_p (SPARSESET)                                     \
 159        && (((ITER) = sparseset_iter_elm (SPARSESET)) || 1);             \
 160        sparseset_iter_next (SPARSESET))
 161
 162 #endif /* GCC_SPARSESET_H */