Performance evaluation of a decoded instruction cache for variable instruction-length computers

  • Authors:
  • Gideon Intrater;Ilan Spillinger

  • Affiliations:
  • -;-

  • Venue:
  • ISCA '92 Proceedings of the 19th annual international symposium on Computer architecture
  • Year:
  • 1992

Quantified Score

Hi-index 0.00

Visualization

Abstract

A Decoded INstruction Cache (DINC) serves as a buffer between the instruction decoder and the other instruction-pipeline stages. In this paper we explain how techniques that reduce the branch penalty based on such a cache, can improve CPU performance. We analyze the impact of some of the design parameters of DINCs on variable instruction-length computers, e.g., CISC machines.Our study indicates that tuning the mapping function of the instructions into the cache, can improve the performance substantially. This tuning must be based on the instruction length distribution for a specific architecture. In addition, the associativity degree has a greater effect on the DINC's performance, than on the performance of regular caches. We also discuss the difference between the performance of DINCs and other caches, when longer cache lines are used. The results presented were obtained by both analytical study and trace-driven simulations of several integer UNIX applications.