Invention Grant
US08555040B2 Indirect branch target predictor that prevents speculation if mispredict is expected
有权
间接分支目标预测器,如果预期有误预测,则可以防止投机
- Patent Title: Indirect branch target predictor that prevents speculation if mispredict is expected
- Patent Title (中): 间接分支目标预测器,如果预期有误预测,则可以防止投机
-
Application No.: US12785939Application Date: 2010-05-24
-
Publication No.: US08555040B2Publication Date: 2013-10-08
- Inventor: Andrew J. Beaumont-Smith , Ramesh Gunna
- Applicant: Andrew J. Beaumont-Smith , Ramesh Gunna
- Applicant Address: US CA Cupertino
- Assignee: Apple Inc.
- Current Assignee: Apple Inc.
- Current Assignee Address: US CA Cupertino
- Agency: Meyertons, Hood, Kivlin, Kowert & Goetzel, P.C.
- Agent Lawrence J. Merkel
- Main IPC: G06F9/32
- IPC: G06F9/32

Abstract:
In one embodiment, a processor implements an indirect branch target predictor to predict target addresses of indirect branch instructions. The indirect branch target predictor may store target addresses generated during previous executions of indirect branches, and may use the stored target addresses as predictions for current indirect branches. The indirect branch target predictor may also store a validation tag corresponding to each stored target address. The validation tag may be compared to similar data corresponding to the current indirect branch being predicted. If the validation tag does not match, the indirect branch is presumed to be mispredicted (since the branch target address actually belongs to a different instruction). The indirect branch target predictor may inhibit speculative execution subsequent to the mispredicted indirect branch until the redirect is signalled for the mispredicted indirect branch.
Public/Granted literature
- US20110289300A1 Indirect Branch Target Predictor that Prevents Speculation if Mispredict Is Expected Public/Granted day:2011-11-24
Information query