A data processing apparatus includes a three input arithmetic logic unit (230) that generates a combination of the three inputs that is selected by a function signal. Data registers (200) store the three data inputs and the arithmetic logic unit output. The second input signal comes from a controllable...http://www.google.com.au/patents/US5590350?utm_source=gb-gplus-sharePatent US5590350 - Three input arithmetic logic unit with mask generator
