A cellular array processor (10) for efficiently performing data dependent processing such as floating point arithmetic functions. One module (84) in the array processor (12) generates a signal applied to bus line (24) when all of the bits in a register (86) are zero. The signal on bus line (24) effects the shifting operation of a shift register (36) in a memory module (34) located on a different functional plane. Thus, the processing functions carried out in each elemental processor (26) can be made to depend on the value of data stored therein instead of being dictated solely by a simultaneous executed instruction from the control processor (14) as is the normal case.