Abstract: Disclosed is a data processing system and a method for performing an arithmetic operation on a plurality of signed data values. In the data processing system and the method, there is a first step in which two or more signed data values are encoded into a composite value and an arithmetic operation is applied to the composite value to produce an encoded result. The encoded result can then be decoded to produce final results where each final result represents the application of the arithmetic operation to a corresponding signed data value. Thus, by using the encoded composite value, a single arithmetic operation can be applied simultaneously to multiple data values and the result then decoded. The decoded result represents the result of applying the arithmetic operation to each data value separately. The advantage of this operation is that operations can be formed on multiple data values without requiring the provision of dedicated hardware or new instructions as required by the prior art.

Abstract: When performing data processing operations upon data words 2, 4 including a plurality of abutting data values a0, a1, a2, a3, b0, b1, b2 and b3 the results of the operation upon one data value may influence a neighboring data value in an undesired manner. An error correcting value 34 may be determined from the input data words 2, 4 and then combined with the intermediate result 32 to correct for any undesired interactions between adjacent data values.