gcc/bitmap.h

   1 /* Functions to support general ended bitmaps.
   2    Copyright (C) 1997 Free Software Foundation, Inc.
   3
   4 This file is part of GNU CC.
   5
   6 GNU CC is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2, or (at your option)
   9 any later version.
  10
  11 GNU CC is distributed in the hope that it will be useful,
  12 but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 GNU General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU CC; see the file COPYING.  If not, write to
  18 the Free Software Foundation, 59 Temple Place - Suite 330,
  19 Boston, MA 02111-1307, USA.  */
  20
  21 /* Number of words to use for each element in the linked list.  */
  22
  23 #ifndef BITMAP_ELEMENT_WORDS
  24 #define BITMAP_ELEMENT_WORDS 2
  25 #endif
  26
  27 /* Number of bits in each actual element of a bitmap.  We get slightly better
  28    code for bit % BITMAP_ELEMENT_ALL_BITS and bit / BITMAP_ELEMENT_ALL_BITS if
  29    bits is unsigned, assuming it is a power of 2.  */
  30
  31 #define BITMAP_ELEMENT_ALL_BITS \
  32   ((unsigned) (BITMAP_ELEMENT_WORDS * HOST_BITS_PER_WIDE_INT))
  33
  34 /* Bitmap set element.  We use a linked list to hold only the bits that
  35    are set.  This allows for use to grow the bitset dynamically without
  36    having to realloc and copy a giant bit array.  The `prev' field is
  37    undefined for an element on the free list.  */
  38
  39 typedef struct bitmap_element_def
  40 {
  41   struct bitmap_element_def *next;              /* Next element. */
  42   struct bitmap_element_def *prev;              /* Previous element. */
  43   unsigned int indx;                    /* regno/BITMAP_ELEMENT_ALL_BITS. */
  44   unsigned HOST_WIDE_INT bits[BITMAP_ELEMENT_WORDS]; /* Bits that are set. */
  45 } bitmap_element;
  46
  47 /* Head of bitmap linked list.  */
  48 typedef struct bitmap_head_def {
  49   bitmap_element *first;        /* First element in linked list. */
  50   bitmap_element *current;      /* Last element looked at. */
  51   int indx;                     /* Index of last element looked at. */
  52 } bitmap_head, *bitmap;
  53
  54 /* Enumeration giving the various operations we support.  */
  55 enum bitmap_bits {
  56   BITMAP_AND,                   /* TO = FROM1 & FROM2 */
  57   BITMAP_AND_COMPL,             /* TO = FROM1 & ~ FROM2 */
  58   BITMAP_IOR                    /* TO = FROM1 | FROM2 */
  59 };
  60
  61 /* Global data */
  62 extern bitmap_element *bitmap_free;     /* Freelist of bitmap elements */
  63 extern bitmap_element bitmap_zero;      /* Zero bitmap element */
  64
  65 /* Clear a bitmap by freeing up the linked list.  */
  66 extern void bitmap_clear PROTO((bitmap));
  67
  68 /* Copy a bitmap to another bitmap. */
  69 extern void bitmap_copy PROTO((bitmap, bitmap));
  70
  71 /* Perform an operation on two bitmaps, yielding a third.  */
  72 extern void bitmap_operation PROTO((bitmap, bitmap, bitmap, enum bitmap_bits));
  73
  74 /* `or' into one bitmap the `and' of a second bitmap witih the complement
  75    of a third.  */
  76 extern void bitmap_ior_and_compl PROTO((bitmap, bitmap, bitmap));
  77
  78 /* Clear a single register in a register set.  */
  79 extern void bitmap_clear_bit PROTO((bitmap, int));
  80
  81 /* Set a single register in a register set.  */
  82 extern void bitmap_set_bit PROTO((bitmap, int));
  83
  84 /* Return true if a register is set in a register set.  */
  85 extern int bitmap_bit_p PROTO((bitmap, int));
  86
  87 /* Debug functions to print a bitmap linked list.  */
  88 extern void bitmap_debug PROTO((bitmap));
  89 extern void bitmap_debug_file STDIO_PROTO((FILE *, bitmap));
  90
  91 /* Initialize a bitmap header.  */
  92 extern bitmap bitmap_initialize PROTO((bitmap));
  93
  94 /* Release all memory held by bitmaps.  */
  95 extern void bitmap_release_memory PROTO((void));
  96
  97 /* Allocate a bitmap with oballoc.  */
  98 #define BITMAP_OBSTACK_ALLOC(OBSTACK)                           \
  99   bitmap_initialize ((bitmap) obstack_alloc (OBSTACK, sizeof (bitmap_head)))
 100
 101 /* Allocate a bitmap with alloca.  */
 102 #define BITMAP_ALLOCA()                                         \
 103   bitmap_initialize ((bitmap) alloca (sizeof (bitmap_head)))
 104
 105 /* Do any cleanup needed on a bitmap when it is no longer used.  */
 106 #define BITMAP_FREE(BITMAP)                                     \
 107 do {                            \
 108   if (BITMAP)                   \
 109     {                           \
 110       bitmap_clear (BITMAP);    \
 111       (BITMAP) = 0;             \
 112     }                                                                   \
 113 } while (0)
 114
 115 /* Do any one-time initializations needed for bitmaps.  */
 116 #define BITMAP_INIT_ONCE()
 117
 118 /* Loop over all bits in BITMAP, starting with MIN, setting BITNUM to the
 119    bit number and executing CODE for all bits that are set. */
 120
 121 #define EXECUTE_IF_SET_IN_BITMAP(BITMAP, MIN, BITNUM, CODE)             \
 122 do {                                                                    \
 123   bitmap_element *ptr_ = (BITMAP)->first;                               \
 124   unsigned int indx_ = (MIN) / BITMAP_ELEMENT_ALL_BITS;                 \
 125   unsigned bit_num_ = (MIN) % ((unsigned) HOST_BITS_PER_WIDE_INT);      \
 126   unsigned word_num_ = (((MIN) / ((unsigned) HOST_BITS_PER_WIDE_INT))   \
 127                         % BITMAP_ELEMENT_WORDS);                        \
 128                                                                         \
 129                                                                         \
 130   /* Find the block the minimum bit is in.  */                          \
 131   while (ptr_ != 0 && ptr_->indx < indx_)                               \
 132     ptr_ = ptr_->next;                                                  \
 133                                                                         \
 134   if (ptr_ != 0 && ptr_->indx != indx_)                                 \
 135     {                                                                   \
 136       bit_num_ = 0;                                                     \
 137       word_num_ = 0;                                                    \
 138     }                                                                   \
 139                                                                         \
 140   for (; ptr_ != 0; ptr_ = ptr_->next)                                  \
 141     {                                                                   \
 142       for (; word_num_ < BITMAP_ELEMENT_WORDS; word_num_++)             \
 143         {                                                               \
 144           unsigned HOST_WIDE_INT word_ = ptr_->bits[word_num_];         \
 145                                                                         \
 146           if (word_ != 0)                                               \
 147             {                                                           \
 148               for (; bit_num_ < HOST_BITS_PER_WIDE_INT; bit_num_++)     \
 149                 {                                                       \
 150                   unsigned HOST_WIDE_INT mask_                          \
 151                     = ((unsigned HOST_WIDE_INT) 1) << bit_num_;         \
 152                                                                         \
 153                   if ((word_ & mask_) != 0)                             \
 154                     {                                                   \
 155                       word_ &= ~ mask_;                                 \
 156                       (BITNUM) = (ptr_->indx * BITMAP_ELEMENT_ALL_BITS  \
 157                                   + word_num_ * HOST_BITS_PER_WIDE_INT  \
 158                                   + bit_num_);                          \
 159                       CODE;                                             \
 160                                                                         \
 161                       if (word_ == 0)                                   \
 162                         break;                                          \
 163                     }                                                   \
 164                 }                                                       \
 165             }                                                           \
 166                                                                         \
 167           bit_num_ = 0;                                                 \
 168         }                                                               \
 169                                                                         \
 170       word_num_ = 0;                                                    \
 171     }                                                                   \
 172 } while (0)
 173
 174 /* Loop over all bits in BITMAP1 and BITMAP2, starting with MIN, setting
 175    BITNUM to the bit number and executing CODE for all bits that are set in
 176    the first bitmap and not set in the second. */
 177
 178 #define EXECUTE_IF_AND_COMPL_IN_BITMAP(BITMAP1, BITMAP2, MIN, BITNUM, CODE) \
 179 do {                                                                    \
 180   bitmap_element *ptr1_ = (BITMAP1)->first;                             \
 181   bitmap_element *ptr2_ = (BITMAP2)->first;                             \
 182   unsigned int indx_ = (MIN) / BITMAP_ELEMENT_ALL_BITS;                 \
 183   unsigned bit_num_ = (MIN) % ((unsigned) HOST_BITS_PER_WIDE_INT);      \
 184   unsigned word_num_ = (((MIN) / ((unsigned) HOST_BITS_PER_WIDE_INT))   \
 185                         % BITMAP_ELEMENT_WORDS);                        \
 186                                                                         \
 187   /* Find the block the minimum bit is in in the first bitmap.  */      \
 188   while (ptr1_ != 0 && ptr1_->indx < indx_)                             \
 189     ptr1_ = ptr1_->next;                                                \
 190                                                                         \
 191   if (ptr1_ != 0 && ptr1_->indx != indx_)                               \
 192     {                                                                   \
 193       bit_num_ = 0;                                                     \
 194       word_num_ = 0;                                                    \
 195     }                                                                   \
 196                                                                         \
 197   for (; ptr1_ != 0 ; ptr1_ = ptr1_->next)                              \
 198     {                                                                   \
 199       /* Advance BITMAP2 to the equivalent link, using an all           \
 200          zero element if an equavialent link doesn't exist.  */         \
 201       bitmap_element *tmp2_;                                            \
 202                                                                         \
 203       while (ptr2_ != 0 && ptr2_->indx < ptr1_->indx)                   \
 204         ptr2_ = ptr2_->next;                                            \
 205                                                                         \
 206       tmp2_ = ((ptr2_ != 0 && ptr2_->indx == ptr1_->indx)               \
 207                ? ptr2_ : &bitmap_zero);                                 \
 208                                                                         \
 209       for (; word_num_ < BITMAP_ELEMENT_WORDS; word_num_++)             \
 210         {                                                               \
 211           unsigned HOST_WIDE_INT word_ = (ptr1_->bits[word_num_]        \
 212                                           & ~ tmp2_->bits[word_num_]);  \
 213           if (word_ != 0)                                               \
 214             {                                                           \
 215               for (; bit_num_ < HOST_BITS_PER_WIDE_INT; bit_num_++)     \
 216                 {                                                       \
 217                   unsigned HOST_WIDE_INT mask_                          \
 218                     = ((unsigned HOST_WIDE_INT)1) << bit_num_;          \
 219                                                                         \
 220                   if ((word_ & mask_) != 0)                             \
 221                     {                                                   \
 222                       word_ &= ~ mask_;                                 \
 223                       (BITNUM) = (ptr1_->indx * BITMAP_ELEMENT_ALL_BITS \
 224                                   + word_num_ * HOST_BITS_PER_WIDE_INT  \
 225                                   + bit_num_);                          \
 226                                                                         \
 227                       CODE;                                             \
 228                       if (word_ == 0)                                   \
 229                         break;                                          \
 230                     }                                                   \
 231                 }                                                       \
 232             }                                                           \
 233                                                                         \
 234           bit_num_ = 0;                                                 \
 235         }                                                               \
 236                                                                         \
 237       word_num_ = 0;                                                    \
 238     }                                                                   \
 239 } while (0)