Patent · US Expired

Speculative scheduling of instructions with source operand validity bit and rescheduling upon carried over destination operand invalid bit detection

US6925550B2 · kind B2 · utility

14Cited by
8References
23Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 2, 2002
Grant dateAug 2, 2005
Priority date
Expiry dateJul 24, 2023

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F9/3858
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A method and apparatus to execute data speculative instructions in a processor comprising at least one source register, each source register comprising a bit to indicate validity of data in the at least one source register. A data validity circuit coupled to the one or more source registers to determine the validity of the data in the source registers, and to indicate the validity of the data in a destination register based upon the validity bit in the at least one source register. The processor optionally comprising a checker unit to retire those instructions from the execution unit which write valid data to the destination register, and to re-schedules those instructions for execution which write invalid data to the destination register.

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