Exemple #1
0
size_t
gfc_merge_initializers (gfc_typespec ts, gfc_expr *e, unsigned char *data,
			unsigned char *chk, size_t length)
{
  size_t len = 0;
  gfc_constructor * c;

  switch (e->expr_type)
    {
    case EXPR_CONSTANT:
    case EXPR_STRUCTURE:
      len = expr_to_char (e, &data[0], &chk[0], length);

      break;

    case EXPR_ARRAY:
      for (c = e->value.constructor; c; c = c->next)
	{
	  size_t elt_size = gfc_target_expr_size (c->expr);

	  if (c->n.offset)
	    len = elt_size * (size_t)mpz_get_si (c->n.offset);

	  len = len + gfc_merge_initializers (ts, c->expr, &data[len],
					      &chk[len], length - len);
	}
      break;

    default:
      return 0;
    }

  return len;
}
Exemple #2
0
static tree
get_init_field (segment_info *head, tree union_type, tree *field_init,
		record_layout_info rli)
{
  segment_info *s;
  HOST_WIDE_INT length = 0;
  HOST_WIDE_INT offset = 0;
  unsigned HOST_WIDE_INT known_align, desired_align;
  bool overlap = false;
  tree tmp, field;
  tree init;
  unsigned char *data, *chk;
  VEC(constructor_elt,gc) *v = NULL;

  tree type = unsigned_char_type_node;
  int i;

  /* Obtain the size of the union and check if there are any overlapping
     initializers.  */
  for (s = head; s; s = s->next)
    {
      HOST_WIDE_INT slen = s->offset + s->length;
      if (s->sym->value)
	{
	  if (s->offset < offset)
            overlap = true;
	  offset = slen;
	}
      length = length < slen ? slen : length;
    }

  if (!overlap)
    return NULL_TREE;

  /* Now absorb all the initializer data into a single vector,
     whilst checking for overlapping, unequal values.  */
  data = XCNEWVEC (unsigned char, (size_t)length);
  chk = XCNEWVEC (unsigned char, (size_t)length);

  /* TODO - change this when default initialization is implemented.  */
  memset (data, '\0', (size_t)length);
  memset (chk, '\0', (size_t)length);
  for (s = head; s; s = s->next)
    if (s->sym->value)
      gfc_merge_initializers (s->sym->ts, s->sym->value,
			      &data[s->offset],
			      &chk[s->offset],
			     (size_t)s->length);
  
  for (i = 0; i < length; i++)
    CONSTRUCTOR_APPEND_ELT (v, NULL, build_int_cst (type, data[i]));

  free (data);
  free (chk);

  /* Build a char[length] array to hold the initializers.  Much of what
     follows is borrowed from build_field, above.  */

  tmp = build_int_cst (gfc_array_index_type, length - 1);
  tmp = build_range_type (gfc_array_index_type,
			  gfc_index_zero_node, tmp);
  tmp = build_array_type (type, tmp);
  field = build_decl (gfc_current_locus.lb->location,
		      FIELD_DECL, NULL_TREE, tmp);

  known_align = BIGGEST_ALIGNMENT;

  desired_align = update_alignment_for_field (rli, field, known_align);
  if (desired_align > known_align)
    DECL_PACKED (field) = 1;

  DECL_FIELD_CONTEXT (field) = union_type;
  DECL_FIELD_OFFSET (field) = size_int (0);
  DECL_FIELD_BIT_OFFSET (field) = bitsize_zero_node;
  SET_DECL_OFFSET_ALIGN (field, known_align);

  rli->offset = size_binop (MAX_EXPR, rli->offset,
                            size_binop (PLUS_EXPR,
                                        DECL_FIELD_OFFSET (field),
                                        DECL_SIZE_UNIT (field)));

  init = build_constructor (TREE_TYPE (field), v);
  TREE_CONSTANT (init) = 1;

  *field_init = init;

  for (s = head; s; s = s->next)
    {
      if (s->sym->value == NULL)
	continue;

      gfc_free_expr (s->sym->value);
      s->sym->value = NULL;
    }

  return field;
}