Invention Grant
- Patent Title: Branch misprediction recovery mechanism for microprocessors
- Patent Title (中): 微处理器分支错误预测恢复机制
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Application No.: US12346349Application Date: 2008-12-30
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Publication No.: US08099586B2Publication Date: 2012-01-17
- Inventor: Yuan C. Chou , Robert T. Golla , Mark A. Luttrell , Paul J. Jordan , Manish Shah
- Applicant: Yuan C. Chou , Robert T. Golla , Mark A. Luttrell , Paul J. Jordan , Manish Shah
- Applicant Address: US CA Redwood City
- Assignee: Oracle America, Inc.
- Current Assignee: Oracle America, Inc.
- Current Assignee Address: US CA Redwood City
- Agency: Meyertons, Hood, Kivlin, Kowert & Goetzel, P.C.
- Agent Rory D. Rankin
- Main IPC: G06F9/00
- IPC: G06F9/00

Abstract:
A system and method for reducing branch misprediction penalty. In response to detecting a mispredicted branch instruction, circuitry within a microprocessor identifies a predetermined condition prior to retirement of the branch instruction. Upon identifying this condition, the entire corresponding pipeline is flushed prior to retirement of the branch instruction, and instruction fetch is started at a corresponding address of an oldest instruction in the pipeline immediately prior to the flushing of the pipeline. The correct outcome is stored prior to the pipeline flush. In order to distinguish the mispredicted branch from other instructions, identification information may be stored alongside the correct outcome. One example of the predetermined condition being satisfied is in response to a timer reaching a predetermined threshold value, wherein the timer begins incrementing in response to the mispredicted branch detection and resets at retirement of the mispredicted branch.
Public/Granted literature
- US20100169611A1 BRANCH MISPREDICTION RECOVERY MECHANISM FOR MICROPROCESSORS Public/Granted day:2010-07-01
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