Patent · US Expired

Cache bypass control for operand fetches

US4189770A · kind A · utility

29Cited by
5References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 16, 1978
Grant dateFeb 19, 1980
Priority date
Expiry dateMar 16, 1998

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F12/0886
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

In the case of a cache miss, the successive fetch requests by the I-unit for sublines (e.g. doublewords) of a variable length field operand are provided by the first through the highest-address fetched sublines in a line being accessed from main storage via a cache bypass. This avoids the time delay for the I-unit caused by waiting until the complete line has been transferred to the cache before all required sublines in the line are obtainable from the cache. Address operand pairs (AOP's) consisting of request and buffer registers are provided in the I-unit to handle the fetched sublines as fast as the cache bypass can provide them from main storage. If there is a cache hit, the sublines are accessed from the cache.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.