A processor is described including a plurality of data path elements 2, 4, 6, 8 which independently perform in parallel different data processing operations. Program instructions are provided which are decoded to generate control signals for controlling the data path elements. Multiple instruction sets are supported with the same data processing operation to be performed by the same data path element being differently encoded within different instructions of different instruction sets. This enables code compaction when little parallelism may be achieved and full parallelism to be specified when this is possible.