A self-reparable semiconductor includes M functional units each including N sub-functional units. Each of the M functional units performs the same function. First ones of the N sub-functional units communicate with second ones of the N sub-functional units over a signal path that passes through third ones of the N sub-functional units. P spare sub-functional units are functionally interchangeable with P of the N sub-functional units. M, N and P are integers greater than one. Switching devices selectively replace at least one of the N sub-functional units of at least one of the M functional units with at least one of the P spare sub-functional units. Corresponding ones of the N sub-functional units of the M functional units perform the same function. The N sub-functional units within each of the M functional units perform different functions.