A processor includes a memory port for accessing a physical memory under control of an address. A processing unit executing instructions stored in the memory and/or operates on data stored in the memory. An address generation unit ("AGU") generates address for controlling access to the memory; the AGU being associated with a plurality of N registers enabling the AGU to generate the address under control of an address generation mechanism. A memory unit is operative to save/load k of the N registers, where 2<=k<=N, triggered by one operation. To this end, the memory unit includes a concatenator for concatenating the k registers to one memory word to be written to the memory through the memory port and a splitter for separating a word read from the memory through the memory port into the k registers.