The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 16, 2010
Filed:
Sep. 14, 2004
Alexander Edward Nancekievill, Cambridge, GB;
Alexander Edward Nancekievill, Cambridge, GB;
ARM Limited, Cambridge, GB;
Abstract
A data processing systemincorporating an instruction pipelineand a prefetch unitis provided with a branch prediction mechanism using both a branch prediction memorystoring 1-bit values indicating strongly taken or strongly not taken together with a branch prediction cache indicating for certain selected branch history values either weakly taken or weakly not taken predictions. When a conditional branch instruction is encountered, then the preceding branch prediction history is used to access a first prediction within the branch prediction memoryand is looked up to check for a hit within the branch prediction cache. If a hit occurs, then a second prediction within the branch prediction cacheis used in preference to the first prediction, otherwise the first prediction is used. The misprediction by a first prediction value stored within the branch prediction memorytriggers a second prediction to be cached within the branch prediction cachecorresponding to that mispredicted history value.