Patent ID: 6958718

Claim:
Apparatus for processing data, said apparatus comprising: a register data store operable to store data to be processed and accessed via registers corresponding to respective portions of said register data store; processing logic operable to perform data processing operations upon data stored with said register data store; and an instruction decoder responsive to a program instruction to generate control signals operable to control said processing logic to perform a data processing operation specified by said program instruction; wherein said instruction decoder is responsive to a table lookup extension instruction specifying one or more index registers storing a plurality of index values and one or more table registers storing a plurality of data elements to store into respective locations within one or more result registers a plurality of data elements selected from said one or more table registers in dependence upon respective index values from said one or more index registers, said instruction decoder being responsive to an index value outside of a predetermined range of index values to preserve a current value stored in a corresponding location within said one or more result registers.