a method and apparatus for performing fast clip - testing operations in a general purpose processor are provided . this is accomplished by executing a single instruction for comparing a first value x to a second value y and , as a result of the comparison , determining whether x is less than y and whether x - is less than negative y . the values x and y are stored in respective source registers of the processor specified by the instruction . finally , as a result of the determination , one or more binary values representing the results of the determination are inserted into a destination register of the processor also specified by the instruction . accordingly , the invention advantageously provides a general purpose processor with the ability to execute a clip - testing function with a single instruction compared with prior art general purpose processors that require multiple instructions to perform the same function . thus , the general purpose processor of the present invention allows for more efficient and faster clip - testing operations .