A method for rapidly mapping a bitmask returned by a Single Instruction Multiple Data (SIMD) computer compare instruction is provided. A user supplied partitioned mapping variable includes multiple mapping elements. Each of the multiple mapping elements is applied to the inputs of a different one of multiple digital multiplexers. The bitmask returned by the SIMD compare instruction is applied to the selects or all of the multiple digital multiplexers. Each multiplexer outputs one bit, as selected by the bitmask, from the respective mapping element applied to each multiplexer. The one bit outputs are accumulated in a mapped output variable as a mapped bitmask.