Does having a separate subtractor from the adder in an ALU provide a (however small) speed advantage? Or is it universally better to just use the adder for both operations.
I'm thinking that having a separate subtractor would save you about two gate delays - and one of them being an XOR gate, but I'm wondering if the added space of an additional subtractor might increase the amount of time for a signal to pass through the ALU.
I'm thinking that having a separate subtractor would save you about two gate delays - and one of them being an XOR gate, but I'm wondering if the added space of an additional subtractor might increase the amount of time for a signal to pass through the ALU.