Patent · US Expired

Parallel processing with improved instruction misalignment detection

US5504923A · kind A · utility

10Cited by
9References
6Claims
0Family size

Assignee

Inventor

Key dates

Filing dateSep 19, 1994
Grant dateApr 2, 1996
Priority date
Expiry dateSep 19, 2014

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F9/3816
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

Availability flag registers are used for storing flags ia1-ia4 indicating the availability of instructions IR1-IR4 stored in an instruction register. The flags ia1-ia4 are controlled in accordance with misalignment information which represents the degree of an address accessing an instruction cache being shifted from a four word boundary. Upon determining whether or not issuance of an instruction from instruction decoder is possible, it is determined to be unissuable if an availability flag corresponding to each instruction is off. A logic structure for nullifying an instruction stored in an instruction register, when an address in accessing instruction cache 1 is shifted from the four word boundary is implemented without providing the instruction register with a resetting function, and thus a circuit for implementing this logic can be constructed with a reduced number of transistors.

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