Patent · US Expired

Speculative instruction issue in a simultaneously multithreaded processor

US7366877B2 · kind B2 · utility

7Cited by
21References
14Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 17, 2003
Grant dateApr 29, 2008
Priority date
Expiry dateApr 28, 2025

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F9/3851
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A method for optimizing throughput in a microprocessor that is capable of processing multiple threads of instructions simultaneously. Instruction issue logic is provided between the input buffers and the pipeline of the microprocessor. The instruction issue logic speculatively issues instructions from a given thread based on the probability that the required operands will be available when the instruction reaches the stage in the pipeline where they are required. Issue of an instruction is blocked if the current pipeline conditions indicate that there is a significant probability that the instruction will need to stall in a shared resource to wait for operands. Once the probability that the instruction will stall is below a certain threshold, based on current pipeline conditions, the instruction is allowed to issue.

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