Patent · US Expired

Millimode capable computer system providing global branch history table disables and separate millicode disables which enable millicode disable to be turned off for some sections of code execution but not disabled for all

US6125444A · kind A · utility

13Cited by
5References
14Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 30, 1998
Grant dateSep 26, 2000
Priority date
Expiry dateApr 30, 2018

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F9/3844
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A millimode capable computer system provides control to millicode to allow the BHT operations to continue except when the these special situations occur that require control of instruction fetch operations must be provided and the BHT can be turned off for some sections of code execution, but not disabled for all. A single free running BHT functions for both a normal mode and a millimode for the central processor which can execute in millimode with a branch history table directing instruction fetch for which both a global BHT disable and millicode disables exist. Hit detection logic receives input from the global BHT disable, as well as from an initialized control register bit and a processor control register bit to select the correct set target information and generate a "branch history table hit detected" control signal.

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