241             chips = set(getattr(regmap, 'chips', ['undef']))
244             self.__chips.update(chips)
257                     other.chips = sorted(list(chips.union(other_chips)))
272                    type_ref != other_type_ref and chips.intersection(other_chips):
539     def chips(self):  member in RegisterDatabase
546     def merge_chips(self, chips, newchip):  argument
553         chips = set(chips)
562             if chips.isdisjoint(regmap.chips):
568                 if chips.isdisjoint(other.chips):
664                 regmap_accum.chips = [newchip]
668             joining_chips = chips.intersection(regmap.chips)
672             remaining_chips = set(regmap.chips).difference(chips)
676                 regmap.chips = sorted(remaining_chips.union([newchip]))
682                 regmap.chips = sorted(remaining_chips)
719                 chips = getattr(regmap, 'chips', [])
720                 suffix = '_' + chips[0] if chips else ''