In one example, an apparatus comprises: a buffer memory; and a memory access circuit configured to: fetch, from a first memory, a set of first groups of data elements of a first matrix, each first group of data elements being stored at consecutive memory addresses at the first memory; based on a first configuration, store the set of first groups of data elements at consecutive memory addresses or at non-consecutive memory addresses at the buffer memory; based on a second configuration that defines a memory address offset, fetch a set of second groups of the data elements from the buffer memory, each second group of the data elements being stored at consecutive memory addresses of the buffer memory, each second group being separated by the memory address offset in the buffer memory; and store each fetched second group at consecutive addresses of a destination memory to form a second matrix.