Abstract: A data processing apparatus which processes data held in memory. The data processing apparatus includes an address operation unit which obtains an address to read one-word data from the memory, wherein the one-word data is a unit of data access to the memory, and a logical operation unit which determines a content of an operation on a field basis based on information which designates the number of bits per field to construct one-word data with a plurality of fields having a same number of bits. The logical operation unit, based on the content thus determined, performs the operation in parallel on the fields of the one-word data read from the memory by the address thus obtained.