Characterization and exploitation of narrow-width loads

Abstract

This paper exploits small-value locality to accelerate the execution of memory instructions. We find that narrow-width loads (NWLDs) --- loads with small-value operands of 8 bits or less --- comprise 26% of all executed loads across 40 applications of the SPEC benchmark suites. We establish that the frequency of NWLDs are almost independent of compiler and input data. We introduce narrow-width caches (NWC) to cache small-value memory words. NWCs provide a significant speedup for several memory-intensive applications with a negligible chip-area overhead. NWCs also reduce the overall energy dissipation and memory traffic.