METHOD AND SYSTEM FOR A RESULT CODE FOR A SINGLE-INSTRUCTION MULTIPLE-DATA PREDICATE COMPARE OPERATION

A method and system is disclosed which summarizes the results of a classical single-instruction multiple-data SIMD predicate comparison operation, signaling whether all comparisons resulted in a false result or true result, and placing that status into a separate status register, such as the Power PC Condition Register. The method and system utilizes first and second status bits to support the signaling whether all element comparisons resulted in true or false. The first status bit is set when all element comparisons resulted in false (i.e. a NOR of all predicate comparison results), and the second status bit is set when all element comparisons resulted in true (i.e. an AND of all predicate comparison results). This capability allows control flow using conditional branching on the event when all comparison results are false or when all comparison results are true. The method and system of the present invention is useful in 3-D graphics such as lighting and trivial acceptance testing where executing down both paths of a branch and then selecting the correct result is not tolerable.