The apparatus provides for efficient implementation of multiple-bit leap-forward LFSRu calculation in a SIMD processor. This provides an accelerated and programmable way to implement LFSR calculations in a SAID processor. Conditional vector exclusive-OR accumulation is used by manipulating the leap-forward matrix, whereby one conditional vector exclusive-OR operation is performed for each column and partial results are accumulated. For an N-wide SIMD this results in close to N times acceleration of leap-forward LFSR calculation without additional resources or dedicated logic.