Patent ID: 7146491

Claim:
A data processing apparatus comprising: a data processing unit operable in response to an instruction to perform a data processing operation on one or more data values; shift logic operable to selectively apply a shift operation to data to produce one of said one or more data values for said data processing operation; a plurality of registers for storing data; the instruction having a register specifier field for identifying a register and a shift specifier field for specifying a shift to be applied to that register's data in order to produce one of said one or more data values for the data processing operation; the register specifier field being allocatable a distinguished value, if the register specifier field has that distinguished value, the shift logic being provided with a predetermined value and being operable to generate one of a plurality of constant values dependent on the shift specified by the shift specifier field, the generated constant value being used as one of said one or more data values for the data processing operation.