-----------------------------------------------------------
This is an automatically generated e-mail. To reply, visit:
http://reviews.gem5.org/r/2296/
-----------------------------------------------------------

Review request for Default.


Repository: gem5


Description
-------

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.


Diffs
-----

  src/cpu/o3/comm.hh a2bb75a474fd 
  src/cpu/o3/commit.hh a2bb75a474fd 
  src/cpu/o3/commit_impl.hh a2bb75a474fd 
  src/cpu/o3/decode.hh a2bb75a474fd 
  src/cpu/o3/decode_impl.hh a2bb75a474fd 
  src/cpu/o3/fetch.hh a2bb75a474fd 
  src/cpu/o3/fetch_impl.hh a2bb75a474fd 
  src/cpu/o3/iew.hh a2bb75a474fd 
  src/cpu/o3/iew_impl.hh a2bb75a474fd 
  src/cpu/o3/rename_impl.hh a2bb75a474fd 

Diff: http://reviews.gem5.org/r/2296/diff/


Testing
-------


Thanks,

Ali Saidi

_______________________________________________
gem5-dev mailing list
[email protected]
http://m5sim.org/mailman/listinfo/gem5-dev

Reply via email to