Approximate multiplication and division for arithmetic data value speculation in a RISC processor

Abstract

Arithmetic data value speculation increases the throughput of a processor by using approximation to speculatively issue instructions dependent on an arithmetic result. This chapter describes new approximate multipliers and dividers. The performance advantage of these units is demonstrated in a practical context through simulation of a 32 bit RISC processor, modified to use these approximate units for arithmetic data value speculation. Instruction throughput improved by more than 15% for some media benchmarks.