- def create_next_terms(self):
-
- _intermediate_terms = []
-
- def add_intermediate_term(value):
- _intermediate_terms.append(value)
-
- # create full adders for this recursive level.
- # this shrinks N terms to 2 * (N // 3) plus the remainder
- for i in self.groups:
- adder_i = MaskedFullAdder(self.output_width)
- self.adders.append((i, adder_i))
- # add both the sum and the masked-carry to the next level.
- # 3 inputs have now been reduced to 2...
- add_intermediate_term(adder_i.sum)
- add_intermediate_term(adder_i.mcarry)
- # handle the remaining inputs.
- if self.n_inputs % FULL_ADDER_INPUT_COUNT == 1:
- add_intermediate_term(self.i.inputs[-1])
- elif self.n_inputs % FULL_ADDER_INPUT_COUNT == 2:
- # Just pass the terms to the next layer, since we wouldn't gain
- # anything by using a half adder since there would still be 2 terms
- # and just passing the terms to the next layer saves gates.
- add_intermediate_term(self.i.inputs[-2])
- add_intermediate_term(self.i.inputs[-1])
- else:
- assert self.n_inputs % FULL_ADDER_INPUT_COUNT == 0
-
- self._intermediate_terms = _intermediate_terms
-