o3: Fix front-end pipeline interlock behavior
Review Request #2296 - Created June 12, 2014 and submitted
| Information | |
|---|---|
| Ali Saidi | |
| gem5 | |
| default | |
| Reviewers | |
| Default | |
Changeset 10251:faaade247267 --------------------------- o3: Fix front-end pipeline interlock behavior The o3 pipeline interlock/stall logic is incorrect. o3 unnecessicarily stalled fetch and decode due to later stages in the pipeline. In general, a stage should usually only consider if it is stalled by the adjacent, downstream stage. Forcing stalls due to later stages creates and results in bubbles in the pipeline. Additionally, o3 stalled the entire frontend (fetch, decode, rename) on a branch mispredict while the ROB is being serially walked to update the RAT (robSquashing). Only should have stalled @ rename.
