a method of operating a processor . the method comprises a first step of fetching an instruction . the instruction includes an instruction opcode , a first data operand bit group corresponding to a first data operand , and a second data operand bit group corresponding to a second data operand . at least one of the first data operand and the second data operand consists of an integer number n bits . the instruction also comprises at least one immediate bit manipulation operand consisting of an integer number m bits , wherein 2 m is less than the integer number n . the method further includes a second step of executing the instruction , comprising the step of manipulating a number of bits of one of the first data operand and the second data operand . finally , the number of manipulated bits is in response to the at least one immediate bit manipulation operand , and the manipulating step is further in response to the instruction opcode .