C++ (Cpp) EBITSET_ZERO_P Examples

Example #1

File: ebitset.c Project: AnotherView/bison

/* Find list of up to NUM bits set in BSET starting from and including
 *NEXT and store in array LIST.  Return with actual number of bits
 found and with *NEXT indicating where search stopped.  */
static bitset_bindex
ebitset_list (bitset bset, bitset_bindex *list,
              bitset_bindex num, bitset_bindex *next)
{
  bitset_bindex bitno;
  bitset_windex windex;
  bitset_windex eindex;
  bitset_bindex count;
  bitset_windex size;
  ebitset_elt *elt;
  bitset_word word;
  ebitset_elts *elts;

  if (EBITSET_ZERO_P (bset))
    return 0;

  bitno = *next;
  count = 0;

  elts = EBITSET_ELTS (bset);
  size = EBITSET_SIZE (bset);
  eindex = bitno / EBITSET_ELT_BITS;

  if (bitno % EBITSET_ELT_BITS)
    {
      /* We need to start within an element.  This is not very common.  */

      elt = elts[eindex];
      if (elt)
        {
          bitset_windex woffset;
          bitset_word *srcp = EBITSET_WORDS (elt);

          windex = bitno / BITSET_WORD_BITS;
          woffset = eindex * EBITSET_ELT_WORDS;

          for (; (windex - woffset) < EBITSET_ELT_WORDS; windex++)
            {
              word = srcp[windex - woffset] >> (bitno % BITSET_WORD_BITS);

              for (; word; bitno++)
                {
                  if (word & 1)
                    {
                      list[count++] = bitno;
                      if (count >= num)
                        {
                          *next = bitno + 1;
                          return count;
                        }
                    }
                  word >>= 1;
                }
              bitno = (windex + 1) * BITSET_WORD_BITS;
            }
        }

      /* Skip to next element.  */
      eindex++;
    }

Example #2

File: table.c Project: cooljeanius/apple-gdb-1824

/* Copy bits from bitset SRC to bitset DST.  Return true if
   bitsets different.  */
static inline bool
tbitset_copy_cmp (bitset dst, bitset src)
{
  if (src == dst)
    return false;

  if (EBITSET_ZERO_P (dst))
    {
      tbitset_copy_ (dst, src);
      return !EBITSET_ZERO_P (src);
    }

  if (tbitset_equal_p (dst, src))
    return false;

  tbitset_copy_ (dst, src);
  return true;
}

Example #3

File: table.c Project: cooljeanius/apple-gdb-1824

/* Set all bits in the bitset to zero.  */
static inline void
tbitset_zero (bitset bset)
{
  if (EBITSET_ZERO_P (bset))
    return;

  tbitset_elts *elts = EBITSET_ELTS (bset);
  for (bitset_windex j = 0; j < EBITSET_SIZE (bset); j++)
    {
      tbitset_elt *elt = elts[j];
      if (elt)
        tbitset_elt_remove (bset, j);
    }

  /* All the bits are zero.  We could shrink the elts.
     For now just mark BSET as known to be zero.  */
  EBITSET_ZERO_SET (bset);
}

Example #4

File: ebitset.c Project: AnotherView/bison

/* Weed out the zero elements from the elts.  */
static inline bitset_windex
ebitset_weed (bitset bset)
{
  ebitset_elts *elts;
  bitset_windex j;
  bitset_windex count;

  if (EBITSET_ZERO_P (bset))
    return 0;

  elts = EBITSET_ELTS (bset);
  count = 0;
  for (j = 0; j < EBITSET_SIZE (bset); j++)
    {
      ebitset_elt *elt = elts[j];

      if (elt)
        {
          if (ebitset_elt_zero_p (elt))
            {
              ebitset_elt_remove (bset, j);
              count++;
            }
        }
      else
        count++;
    }

  count = j - count;
  if (!count)
    {
      /* All the bits are zero.  We could shrink the elts.
         For now just mark BSET as known to be zero.  */
      EBITSET_ZERO_SET (bset);
    }
  else
    EBITSET_NONZERO_SET (bset);

  return count;
}

Example #5

File: table.c Project: cooljeanius/apple-gdb-1824

/* Find list of up to NUM bits set in BSET starting from and including
 *NEXT and store in array LIST.  Return with actual number of bits
 found and with *NEXT indicating where search stopped.  */
static bitset_bindex
tbitset_list_reverse (bitset bset, bitset_bindex *list,
                      bitset_bindex num, bitset_bindex *next)
{
  if (EBITSET_ZERO_P (bset))
    return 0;

  bitset_windex size = EBITSET_SIZE (bset);
  bitset_bindex n_bits = size * EBITSET_ELT_BITS;
  bitset_bindex rbitno = *next;

  if (rbitno >= n_bits)
    return 0;

  tbitset_elts *elts = EBITSET_ELTS (bset);

  bitset_bindex bitno = n_bits - (rbitno + 1);

  bitset_windex windex = bitno / BITSET_WORD_BITS;
  bitset_windex eindex = bitno / EBITSET_ELT_BITS;
  bitset_windex woffset = windex - eindex * EBITSET_ELT_WORDS;

  /* If num is 1, we could speed things up with a binary search
     of the word of interest.  */
  bitset_bindex count = 0;
  unsigned bcount = bitno % BITSET_WORD_BITS;
  bitset_bindex boffset = windex * BITSET_WORD_BITS;

  do
    {
      tbitset_elt *elt = elts[eindex];
      if (elt)
        {
          bitset_word *srcp = EBITSET_WORDS (elt);

          do
            {
              for (bitset_word word = srcp[woffset] << (BITSET_WORD_BITS - 1 - bcount);
                   word; bcount--)
                {
                  if (word & BITSET_MSB)
                    {
                      list[count++] = boffset + bcount;
                      if (count >= num)
                        {
                          *next = n_bits - (boffset + bcount);
                          return count;
                        }
                    }
                  word <<= 1;
                }
              boffset -= BITSET_WORD_BITS;
              bcount = BITSET_WORD_BITS - 1;
            }
          while (woffset--);
        }

      woffset = EBITSET_ELT_WORDS - 1;
      boffset = eindex * EBITSET_ELT_BITS - BITSET_WORD_BITS;
    }
  while (eindex--);

  *next = n_bits - (boffset + 1);
  return count;
}