1. A multimode accessible storage facility that allows block access in a block access mode and row access in a row access mode, the storage facility comprising: a memory unit comprising a plurality of memory banks, each memory hank having a respective bank index, an address generator for generating, for each of said memory banks, a rotated bank address as a function of an input address and a shift parameter, an input vector data rotator for rotating an input vector and for providing vector elements of the rotated input vector to a respective bank of the memory unit, and an output vector rotator for inverse rotating a vector comprising vector elements retrieved from respective banks of the memory unit and for providing the rotated output vector.