[PATCH] Add ISD::FROUND for libm round()

[Hal Finkel]

Ping.

 -Hal

----- Original Message -----
> ----- Original Message -----
> > Hi Hal,
> > 
> > 
> > I think that the round intrinsic should support all of the popular
> > rounding mode, and not only nearest integer.
> 
> I agree, and we do currently, except for the round-away-from-zero
> mode of round(). In libm, the different rounding modes have
> different function calls, and we currently support (have the ability
> to custom lower):
>       FCEIL, FTRUNC, FRINT, FNEARBYINT, FFLOOR,
> 
> which correspond to:
>   ceil - smallest integral value not less than
>   trunc - round to integer, towards zero
>   floor - largest integral value not greater than
>   rint/nearbyint - round to nearest integer using the current
>   rounding mode (which is normally ties-to-even)
> 
> and now I'd like to add the remaining one:
>   round - round to nearest integer, away from zero
> 
> Thanks again,
> Hal
> 
> > 
> > 
> > Thanks,
> > Nadav
> > 
> > 
> > 
> > On Jul 7, 2013, at 9:04 PM, Hal Finkel < hfinkel at anl.gov > wrote:
> > 
> > 
> > 
> > Hello!
> > 
> > round() has been feeling a little left out; all of its friends
> > (like
> > rint() and nearbyint()) have their own ISD nodes, and round()
> > doesn't. Recent PowerPC cores have an instruction for round(), and
> > so I'd like to correct this injustice and add ISD::FROUND.
> > 
> > For the most part, this is extremely straightforward. I've added an
> > intrinsic and matching ISD node just like those for nearbyint() and
> > friends. The SelectionDAG pattern I've named frnd (because
> > ISD::FP_ROUND has already claimed fround); obviously we can use a
> > different name if someone has a better suggestion. Please review.
> > 
> > Thanks again,
> > Hal
> > 
> > --
> > Hal Finkel
> > Assistant Computational Scientist
> > Leadership Computing Facility
> > Argonne National Laboratory
> > <isd_round.patch> _______________________________________________
> > llvm-commits mailing list
> > llvm-commits at cs.uiuc.edu
> > http://lists.cs.uiuc.edu/mailman/listinfo/llvm-commits
> > 
> 
> --
> Hal Finkel
> Assistant Computational Scientist
> Leadership Computing Facility
> Argonne National Laboratory
> _______________________________________________
> llvm-commits mailing list
> llvm-commits at cs.uiuc.edu
> http://lists.cs.uiuc.edu/mailman/listinfo/llvm-commits
> 

-- 
Hal Finkel
Assistant Computational Scientist
Leadership Computing Facility
Argonne National Laboratory