A method and apparatus for implementing FIR filters in a processor includes a plurality of execution units executing instructions of an instruction set. The execution units include a number of FIR filter circuits, each of which is associated with a corresponding one of a number FIR filter instructions. Furthermore, each of the FIR filter circuits is and dedicated exclusively to executing its corresponding one of the FIR filter instructions. Each FIR filter execution unit receives input data and provides filtered output data.