A data processing apparatus comprising: a data store comprising a plurality of storage elements for storing data elements; an instruction decoder configured to decode at least one conditional select instruction, said at least one conditional select instruction specifying a primary source storage element (R n), a secondary source storage element (R m), a condition (Cond), and an operation to be performed on a data element stored in said secondary source storage element, wherein said operation comprises one of incrementing said data element from said secondary source storage element, logically inverting said data element from said secondary source storage element to generate a logically bitwise inverted storage element value or logically inverting said data element from said secondary source storage element and incrementing it to generate an arithmetic negation of said data element; said instruction decoder being configured to output an increment control signal in response to said operation including an incrementing step; a data processor configured to perform data processing operations controlled by said instruction decoder wherein: said data processor comprises an adder configured to receive said data element from said secondary storage element, said data processor being configured to increment said received data element in response to said increment control signal; said data processor is responsive to said decoded at least one conditional select instruction and said condition having a predetermined outcome to perform said operation on said data element from said secondary source storage element (R m) to form a resultant data element (R d); and said data processor is responsive to said decoded at least one conditional select instruction and said condition not having said predetermined outcome to form said resultant data element (R d) from said data element within said primary storage element (R n). a data store comprising a plurality of storage elements for storing data elements; an instruction decoder configured to decode at least one conditional select instruction, said at least one conditional select instruction specifying a primary source storage element (R n), a secondary source storage element (R m), a condition (Cond), and an operation to be performed on a data element stored in said secondary source storage element, wherein said operation comprises one of incrementing said data element from said secondary source storage element, logically inverting said data element from said secondary source storage element to generate a logically bitwise inverted storage element value or logically inverting said data element from said secondary source storage element and incrementing it to generate an arithmetic negation of said data element; said instruction decoder being configured to output an increment control signal in response to said operation including an incrementing step; a data processor configured to perform data processing operations controlled by said instruction decoder wherein: said data processor comprises an adder configured to receive said data element from said secondary storage element, said data processor being configured to increment said received data element in response to said increment control signal; said data processor is responsive to said decoded at least one conditional select instruction and said condition having a predetermined outcome to perform said operation on said data element from said secondary source storage element (R m) to form a resultant data element (R d); and said data processor is responsive to said decoded at least one conditional select instruction and said condition not having said predetermined outcome to form said resultant data element (R d) from said data element within said primary storage element (R n). said data processor comprises an adder configured to receive said data element from said secondary storage element, said data processor being configured to increment said received data element in response to said increment control signal; said data processor is responsive to said decoded at least one conditional select instruction and said condition having a predetermined outcome to perform said operation on said data element from said secondary source storage element (R m) to form a resultant data element (R d); and said data processor is responsive to said decoded at least one conditional select instruction and said condition not having said predetermined outcome to form said resultant data element (R d) from said data element within said primary storage element (R n).