I think that makes sense. I'll put a patch on RB for this soon. Jason
On Wed, Nov 23, 2016 at 5:09 AM Fernando Endo <[email protected]> wrote: > Hi all, > > Then, considering Arthur's answer, I suppose that we can remove > BPredUnit::predictInOrder() rather than updating and not testing it. > > Regards, > > -- > Fernando A. Endo, Post-doc > > INRIA Rennes-Bretagne Atlantique > France > > > 2016-11-21 19:19 GMT+01:00 Arthur Perais <[email protected]>: > > > I suppose it was called by the InOrder CPU once upon a time. Now the > Minor > > CPU uses the same branch prediction code as the o3 CPU, which may have > led > > to the current inconsistencies in how branch predictors handle > out-of-order > > mispredictions (or not :)). > > > > I've submitted a patch regarding this recently ( > > http://reviews.gem5.org/r/3727/), feel free to take a look. > > > > Arthur. > > > > > > > > Le 21/11/2016 à 16:40, Jason Lowe-Power a écrit : > > > >> Hi Fernando, > >> > >> I don't know what he original use of predictInOrder was, but you're > right, > >> it doesn't look like it's in use now. You may be able to figure out what > >> it > >> was used for by inferring its function from the code. > >> > >> Jason > >> > >> On Sun, Nov 13, 2016 at 2:37 PM Jason Lowe-Power <[email protected]> > >> wrote: > >> > >> Hi Fernando, > >>> > >>> I have no idea, off the top of my head. I'd have to look into the code > >>> and/or the history of the file to figure it out. > >>> > >>> I'm busy with an ISCA submission right now, but I can find time to look > >>> into this in a week or so. > >>> > >>> Cheers, > >>> Jason > >>> > >>> On Sun, Nov 13, 2016 at 2:26 PM Fernando Endo < > [email protected]> > >>> wrote: > >>> > >>> Hi Jason, > >>> > >>> I've been working a bit on the integration, and I wondered what is and > >>> where this method is used: > >>> > >>> BPredUnit::predictInOrder() > >>> > >>> I greped the source and built code and did not find a calling point. > >>> > >>> Thanks, > >>> > >>> -- > >>> Fernando A. Endo, Post-doc > >>> > >>> INRIA Rennes-Bretagne Atlantique > >>> France > >>> > >>> > >>> 2016-11-06 21:38 GMT+01:00 Jason Lowe-Power <[email protected]>: > >>> > >>> Hi Fernando, > >>>> > >>>> Yes, it seems like a good idea to include a TAGE predictor in gem5. > >>>> > >>> Please > >>> > >>>> make patches and post them to the reviewboard. We welcome the > >>>> > >>> contribution. > >>> > >>>> Additionally, I believe there was a recent email about a possible bug > >>>> > >>> when > >>> > >>>> updating the branch predictor state on a mis-speculation. If you're > >>>> familiar with this code, or know of a fix for this, we would > appreciate > >>>> a > >>>> patch. Or, if it's actually not broken, that would be great, too. It's > >>>> > >>> part > >>> > >>>> of the code that I'm not very familiar with. > >>>> > >>>> Cheers, > >>>> Jason > >>>> > >>>> On Fri, Nov 4, 2016 at 9:46 AM Fernando Endo < > [email protected]> > >>>> wrote: > >>>> > >>>> Hello all, > >>>> > >>>> I'd like to know if the gem5 community would like to have a TAGE > branch > >>>> prediction in gem5. > >>>> In my branch it seems to be working, so if you give me a positive > >>>> > >>> feedback > >>> > >>>> I may spend some spare time to rebase and test the patch over > >>>> mainstream. > >>>> > >>>> More specifically, I took the CBP2016 winner and removed local > >>>> prediction > >>>> tables. This specific version is called TAGE-GSC (Global Statistical > >>>> Corrector) and should go to src/cpu/pred/tage-gsc.hh. This file is > >>>> functionally equivalent to the original CBP2016 winner and can be > >>>> > >>> compared > >>> > >>>> against it without modification. Then, a glue code was implemented in > >>>> src/cpu/pred/TAGE.hh and src/cpu/pred/TAGE.cc, making tage-gsc.hh to > >>>> work > >>>> in gem5. > >>>> > >>>> I validated the gem5 implementation by comparing the predictor at > fetch > >>>> with a validator at commit. The prediction tables must be the same. > >>>> > >>>> Regards, > >>>> > >>>> -- > >>>> Fernando A. Endo, Post-doc > >>>> > >>>> INRIA Rennes-Bretagne Atlantique > >>>> France > >>>> _______________________________________________ > >>>> gem5-dev mailing list > >>>> [email protected] > >>>> http://m5sim.org/mailman/listinfo/gem5-dev > >>>> _______________________________________________ > >>>> gem5-dev mailing list > >>>> [email protected] > >>>> http://m5sim.org/mailman/listinfo/gem5-dev > >>>> > >>>> _______________________________________________ > >>> gem5-dev mailing list > >>> [email protected] > >>> http://m5sim.org/mailman/listinfo/gem5-dev > >>> > >>> > >>> _______________________________________________ > >> gem5-dev mailing list > >> [email protected] > >> http://m5sim.org/mailman/listinfo/gem5-dev > >> > > > > _______________________________________________ > > gem5-dev mailing list > > [email protected] > > http://m5sim.org/mailman/listinfo/gem5-dev > > > _______________________________________________ > gem5-dev mailing list > [email protected] > http://m5sim.org/mailman/listinfo/gem5-dev > _______________________________________________ gem5-dev mailing list [email protected] http://m5sim.org/mailman/listinfo/gem5-dev
