Fast Modular Zero Sum and Ones Sum Determination

摘要

In one embodiment, a state determiner comprises a plurality of logic circuits and a second logic circuit. Each logic circuit corresponds to a respective bit position of a result of an adder. A first logic circuit corresponds to a least significant bit of the result and is coupled to receive a least significant bit of each operand of the adder and a carry-in input to the adder. Each remaining logic circuit is coupled to receive a respective bit from the respective bit position of each operand and a less significant bit adjacent to the respective bit of each operand. Each logic circuit is configured to generate an output signal indicative of whether or not a specific result occurs in the respective bit position of the result responsive only to inputs that the logic circuit is coupled to receive as stated previously. Coupled to receive the output signals from the logic circuits, the second logic circuit is configured to generate a sum signal indicative, when asserted, that the specific result occurs in each bit position of the result of the adder.