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Re: Remove NOTE_INSN_PREDICTION
> On Wednesday 21 July 2004 19:09, Jan Hubicka wrote:
> > > Hi,
> > >
> > > NOTE_INSN_PREDICTION was only still used for return predictions,
> > > which are broken since the patch to unify return statements for
> > > lower GIMPLE. So we spend a lot of time (computing DOM and PDOM)
> > > in predict.c only to predict a single return with a very poor and
> > > broken prediction.
> > >
> > > With this patch, we no longer predict returns like this. I will
> > > reimplement this in the tree branch prediction code instead.
> > >
> > > Bootstrapped on i686-suse-linux-gnu, testing ongoing. OK when it
> > > passes?
> >
> > Yes, this is OK.
>
> Thanks.
>
>
> > I intended to propose this once we do have replacement
> > for this logic (via branch prediction on trees), but there is no need
> > to keep broken feature around anyway. Tree profiling already replace
> > most of the logic, I just need to find time to do the merge.
>
> You already merged the return predictors. They're also broken
> because we only have one RETURN_EXPR on GIMPLE. But at least
> we can fix those, whereas these RTL predictors are broken beyond
> repair.
Yep, Richard has changed this afterwards. I will fix these ;)
Honza