by vector of allocnos.  */
  bool conflict_vec_p;

  /* The conflict vector or conflict bit vector.  */
  void *vec;

  /* The number of the current element in the vector (of type
     ira_object_t or IRA_INT_TYPE).  */
  unsigned int word_num;

  /* The bit vector size.  It is defined only if
     OBJECT_CONFLICT_VEC_P is FALSE.  */
  unsigned int size;

  /* The current bit index of bit vector.  It is defined only if
     OBJECT_CONFLICT_VEC_P is FALSE.  */
  unsigned int bit_num;

  /* The object id corresponding to the 1st bit of the bit vector.  It
     is defined only if OBJECT_CONFLICT_VEC_P is FALSE.  */
  int base_conflict_id;

  /* The word of bit vector currently visited.  It is defined only if
     OBJECT_CONFLICT_VEC_P is FALSE.  */
  unsigned IRA_INT_TYPE word;
};

/* Initialize the iterator I with ALLOCNO conflicts.  */
static inline void
ira_object_conflict_iter_init (ira_object_conflict_iterator *i,
			       ira_object_t obj)
{
  i->conflict_vec_p = OBJECT_CONFLICT_VEC_P (obj);
  i->vec = OBJECT_CONFLICT_ARRAY (obj);
  i->word_num = 0;
  if (i->conflict_vec_p)
    i->size = i->bit_num = i->base_conflict_id = i->word = 0;
  else
    {
      if (OBJECT_MIN (obj) > OBJECT_MAX (obj))
	i->size = 0;
      else
	i->size = ((OBJECT_MAX (obj) - OBJECT_MIN (obj)
		    + IRA_INT_BITS)
		   / IRA_INT_BITS) * sizeof (IRA_INT_TYPE);
      i->bit_num = 0;
      i->base_conflict_id = OBJECT_MIN (obj);
      i->word = (i->size == 0 ? 0 : ((IRA_INT_TYPE *) i->vec)[0]);
    }
}

/* Return TRUE if we have more conflicting allocnos to visit, in which
   case *A is set to the allocno to be visited.  Otherwise, return
   FALSE.  */
static inline bool
ira_object_conflict_iter_cond (ira_object_conflict_iterator *i,
			       ira_object_t *pobj)
{
  ira_object_t obj;

  if (i->conflict_vec_p)
    {
      obj = ((ira_object_t *) i->vec)[i->word_num++];
      if (obj == NULL)
	return false;
    }
  else
    {
      unsigned IRA_INT_TYPE word = i->word;
      unsigned int bit_num = i->bit_num;

      /* Skip words that are zeros.  */
      for (; word == 0; word = ((IRA_INT_TYPE *) i->vec)[i->word_num])
	{
	  i->word_num++;

	  /* If we have reached the end, break.  */
	  if (i->word_num * sizeof (IRA_INT_TYPE) >= i->size)
	    return false;

	  bit_num = i->word_num * IRA_INT_BITS;
	}

      /* Skip bits that are zero.  */
      for (; (word & 1) == 0; word >>= 1)
	bit_num++;

      obj = ira_object_id_map[bit_num + i->base_conflict_id];
      i->bit_num = bit_num + 1;
      i->word = word >> 1;
    }

  *pobj = obj;
  return true;
}

/* Loop over all objects conflicting with OBJ.  In each iteration,
   CONF is set to the next conflicting object.  ITER is an instance
   of ira_object_conflict_iterator used to iterate the conflicts.  */
#define FOR_EACH_OBJECT_CONFLICT(OBJ, CONF, ITER)			\
  for (ira_object_conflict_iter_init (&(ITER), (OBJ));			\
       ira_object_conflict_iter_cond (&(ITER), &(CONF));)