Adder circuit incorporating byte boundaries

摘要

In accordance with the present invention, an adder is disclosed which combines byte boundary control signals with propagate-generate signal pairs immediately resulting from bit pairs of the input signals. Combining the byte boundary control signals with the first level propagate-generate signal pairs, rather than combining the byte boundary control signals with propagate-generate signal pairs indicative of the carry-out of a byte, allows the adder to utilize a more efficient tree signal path topology in which multiple levels of circuitry may be eliminated, thereby resulting in a reduction in propagation delay.