LOOK-UP TABLE APPARATUS TO PERFORM TWO-BIT ARITHMETIC OPERATION INCLUDING CARRY GENERATION

A look-up table apparatus is provided for performing two-bit arithmetic operation including carry generation. The look-up table is modified to perform two concurrent combinatorial functions, or one function for an increased number of inputs. The look-up table can implement two full adders or subtractors, or two-bit counters, for example. One portion of the modified look-up table provides two bits of a sum output, and another portion of the modified table provides a fast carry out signal for application to a next stage of an adder/subtractor/counter.