Patent · US Expired

Method and apparatus for performing sequential executions of elements in cooperation with a transform

US6715064B1 · kind B1 · utility

43Cited by
5References
23Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 21, 2000
Grant dateMar 30, 2004
Priority date
Expiry dateJan 21, 2020

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG06F9/3848
  • WIPO fieldComputer technology
  • WIPO sectorElectrical engineering

Abstract

A method and apparatus for predicting the outcome of a branch instruction based on the branch history of preceding branch instruction. As a sequence of instructions passes through an instruction execution pipeline, a base branch instruction is chosen, a history index is generated for the base branch instruction and subsequent branch instructions, and a transform is created for the branch instruction to be predicted. When the sequence of instructions subsequently passes through the pipeline again, the transform is used to operate on the history index of the base branch instruction to produce a history index for the branch to be predicted. The result is used as an index into a prediction array to access the prediction logic for the branch instruction being predicted. By using the predetermined transform, a branch status prediction can be made before the branch to be predicted reaches the normal prediction stage in the pipeline.

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