gcc/ebitmap.h

   1 /* Sparse array based bitmaps.
   2    Copyright (C) 2007, 2008, 2009 Free Software Foundation, Inc.
   3
   4 This file is part of GCC.
   5
   6 GCC is free software; you can redistribute it and/or modify it under
   7 the terms of the GNU General Public License as published by the Free
   8 Software Foundation; either version 3, or (at your option) any later
   9 version.
  10
  11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14 for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GCC; see the file COPYING3.  If not see
  18 <http://www.gnu.org/licenses/>.  */
  19
  20 #ifndef GCC_EBITMAP_H
  21 #define GCC_EBITMAP_H
  22
  23 #include "sbitmap.h"
  24
  25 #define EBITMAP_ELT_BITS ((unsigned) HOST_BITS_PER_WIDEST_FAST_INT)
  26 #define EBITMAP_ELT_TYPE unsigned HOST_WIDEST_FAST_INT
  27
  28 typedef struct ebitmap_def
  29 {
  30   unsigned int n_elts;          /* number of elements in the array.  */
  31   sbitmap wordmask;             /* wordmask saying which words are
  32                                    nonzero.  */
  33   unsigned int numwords;        /* number of nonzero words.  */
  34   unsigned int cacheindex;      /* which word cache is.  */
  35   EBITMAP_ELT_TYPE *elts;       /* nonzero element array.  */
  36   EBITMAP_ELT_TYPE *cache;      /* last tested element, or NULL.  */
  37 } *ebitmap;
  38
  39
  40 #define ebitmap_empty_p(MAP) ((MAP)->numwords == 0)
  41 #define ebitmap_free(MAP)  (free((MAP)->elts), \
  42                             sbitmap_free ((MAP)->wordmask),     \
  43                             free((MAP)))
  44
  45 extern void ebitmap_set_bit (ebitmap, unsigned int);
  46 extern void ebitmap_clear_bit (ebitmap, unsigned int);
  47 extern bool ebitmap_bit_p (ebitmap, unsigned int);
  48 extern void dump_ebitmap (FILE *, ebitmap);
  49 extern void dump_ebitmap_file (FILE *, ebitmap);
  50 extern void dump_ebitmap_vector (FILE *, const char *, const char *, ebitmap *,
  51                                  int);
  52 extern ebitmap ebitmap_alloc (unsigned int);
  53 extern ebitmap *ebitmap_vector_alloc (unsigned int, unsigned int);
  54 extern void ebitmap_copy (ebitmap, ebitmap);
  55 extern void ebitmap_and (ebitmap, ebitmap, ebitmap);
  56 extern void ebitmap_and_into (ebitmap, ebitmap);
  57 extern bool ebitmap_and_compl (ebitmap, ebitmap, ebitmap);
  58 extern bool ebitmap_and_compl_into (ebitmap, ebitmap);
  59 extern bool ebitmap_ior_into (ebitmap, ebitmap);
  60 extern bool ebitmap_ior (ebitmap, ebitmap, ebitmap);
  61 extern bool ebitmap_ior_and_compl (ebitmap, ebitmap, ebitmap, ebitmap);
  62 extern bool ebitmap_ior_and_compl_into (ebitmap, ebitmap, ebitmap);
  63 extern bool ebitmap_equal_p (ebitmap, ebitmap);
  64 extern void ebitmap_clear (ebitmap);
  65 extern int ebitmap_last_set_bit (ebitmap);
  66 extern void debug_ebitmap (ebitmap);
  67 extern void dump_ebitmap (FILE *, ebitmap);
  68 extern unsigned long ebitmap_popcount(ebitmap, unsigned long);
  69
  70 /* The iterator for ebitmap.  */
  71 typedef struct {
  72   /* The pointer to the first word of the bitmap.  */
  73   EBITMAP_ELT_TYPE *ptr;
  74
  75   /* Element number inside ptr that we are at.  */
  76   unsigned int eltnum;
  77
  78   /* The size of the bitmap.  */
  79   unsigned int size;
  80
  81   /* Current bit index.  */
  82   unsigned int bit_num;
  83
  84   /* The words currently visited.  */
  85   EBITMAP_ELT_TYPE word;
  86
  87   /* The word mask iterator.  */
  88   sbitmap_iterator maskiter;
  89 } ebitmap_iterator;
  90
  91 static inline void
  92 ebitmap_iter_init (ebitmap_iterator *i, ebitmap bmp, unsigned int min)
  93 {
  94   sbitmap_iter_init (&i->maskiter, bmp->wordmask,
  95                      min / EBITMAP_ELT_BITS);
  96   i->size = bmp->numwords;
  97   if (i->size == 0)
  98     {
  99       i->ptr = NULL;
 100       i->eltnum = 0;
 101       i->bit_num = 0;
 102       i->word = 0;
 103       return;
 104     }
 105   i->ptr = bmp->elts;
 106   i->bit_num = min;
 107   i->eltnum = 0;
 108
 109   if ((min / EBITMAP_ELT_BITS) >= bmp->wordmask->n_bits)
 110     {
 111       i->word = 0;
 112     }
 113   else
 114     {
 115       if (TEST_BIT (bmp->wordmask, min / EBITMAP_ELT_BITS) == 0)
 116         i->word = 0;
 117       else
 118         {
 119           unsigned int wordindex = min / EBITMAP_ELT_BITS;
 120           unsigned int count = sbitmap_popcount (bmp->wordmask, wordindex);
 121           i->word = i->ptr[count] >> (i->bit_num % (unsigned int)EBITMAP_ELT_BITS);
 122           i->eltnum = count + 1;
 123         }
 124     }
 125 }
 126
 127 static inline bool
 128 ebitmap_iter_cond (ebitmap_iterator *i, unsigned int *n)
 129 {
 130   unsigned int ourn = 0;
 131
 132   if (i->size == 0)
 133     return false;
 134
 135   if (i->word == 0)
 136     {
 137       sbitmap_iter_next (&i->maskiter);
 138       if (!sbitmap_iter_cond (&i->maskiter, &ourn))
 139         return false;
 140       i->bit_num = ourn * EBITMAP_ELT_BITS;
 141       i->word = i->ptr[i->eltnum++];
 142     }
 143
 144   /* Skip bits that are zero.  */
 145
 146   for (; (i->word & 1) == 0; i->word >>= 1)
 147     i->bit_num++;
 148
 149   *n = i->bit_num;
 150   return true;
 151 }
 152
 153 static inline void
 154 ebitmap_iter_next (ebitmap_iterator *i)
 155 {
 156   i->word >>= 1;
 157   i->bit_num++;
 158 }
 159
 160 /* Loop over all elements of EBITMAP, starting with MIN.  In each
 161    iteration, N is set to the index of the bit being visited.  ITER is
 162    an instance of ebitmap_iterator used to iterate the bitmap.  */
 163
 164 #define EXECUTE_IF_SET_IN_EBITMAP(EBITMAP, MIN, N, ITER)        \
 165   for (ebitmap_iter_init (&(ITER), (EBITMAP), (MIN));           \
 166        ebitmap_iter_cond (&(ITER), &(N));                       \
 167        ebitmap_iter_next (&(ITER)))
 168
 169
 170 #endif /* ! GCC_EBITMAP_H */