Re: [PATCH 1/3] Inline vect_get_max_nscalars_per_iter

[Richard Biener <rguenther@suse.de>]

On Wed, 14 Jun 2023, Richard Sandiford wrote:

> Richard Biener via Gcc-patches <gcc-patches@gcc.gnu.org> writes:
> > The function is only meaningful for LOOP_VINFO_MASKS processing so
> > inline it into the single use.
> >
> > Bootstrapped and tested on x86_64-unknown-linux-gnu, OK?
> >
> > 	* tree-vect-loop.cc (vect_get_max_nscalars_per_iter): Inline
> > 	into ...
> > 	(vect_verify_full_masking): ... this.
> 
> I think we did have a use for the separate function internally,
> but obviously it was never submitted.  Personally I'd prefer
> to keep things as they are though.

OK - after 3/3 it's no longer "generic" (it wasn't before,
it doesn't inspect the _len groups either), it's only meaningful
for WHILE_ULT style analysis.

> 
> 
> > ---
> >  gcc/tree-vect-loop.cc | 22 ++++++----------------
> >  1 file changed, 6 insertions(+), 16 deletions(-)
> >
> > diff --git a/gcc/tree-vect-loop.cc b/gcc/tree-vect-loop.cc
> > index ace9e759f5b..a9695e5b25d 100644
> > --- a/gcc/tree-vect-loop.cc
> > +++ b/gcc/tree-vect-loop.cc
> > @@ -1117,20 +1117,6 @@ can_produce_all_loop_masks_p (loop_vec_info loop_vinfo, tree cmp_type)
> >    return true;
> >  }
> >  
> > -/* Calculate the maximum number of scalars per iteration for every
> > -   rgroup in LOOP_VINFO.  */
> > -
> > -static unsigned int
> > -vect_get_max_nscalars_per_iter (loop_vec_info loop_vinfo)
> > -{
> > -  unsigned int res = 1;
> > -  unsigned int i;
> > -  rgroup_controls *rgm;
> > -  FOR_EACH_VEC_ELT (LOOP_VINFO_MASKS (loop_vinfo), i, rgm)
> > -    res = MAX (res, rgm->max_nscalars_per_iter);
> > -  return res;
> > -}
> > -
> >  /* Calculate the minimum precision necessary to represent:
> >  
> >        MAX_NITERS * FACTOR
> > @@ -1210,8 +1196,6 @@ static bool
> >  vect_verify_full_masking (loop_vec_info loop_vinfo)
> >  {
> >    unsigned int min_ni_width;
> > -  unsigned int max_nscalars_per_iter
> > -    = vect_get_max_nscalars_per_iter (loop_vinfo);
> >  
> >    /* Use a normal loop if there are no statements that need masking.
> >       This only happens in rare degenerate cases: it means that the loop
> > @@ -1219,6 +1203,12 @@ vect_verify_full_masking (loop_vec_info loop_vinfo)
> >    if (LOOP_VINFO_MASKS (loop_vinfo).is_empty ())
> >      return false;
> >  
> > +  /* Calculate the maximum number of scalars per iteration for every rgroup.  */
> > +  unsigned int max_nscalars_per_iter = 1;
> > +  for (auto rgm : LOOP_VINFO_MASKS (loop_vinfo))
> > +    max_nscalars_per_iter
> > +      = MAX (max_nscalars_per_iter, rgm.max_nscalars_per_iter);
> > +
> >    /* Work out how many bits we need to represent the limit.  */
> >    min_ni_width
> >      = vect_min_prec_for_max_niters (loop_vinfo, max_nscalars_per_iter);
> 

-- 
Richard Biener <rguenther@suse.de>
SUSE Software Solutions Germany GmbH, Frankenstrasse 146, 90461 Nuernberg,
Germany; GF: Ivo Totev, Andrew Myers, Andrew McDonald, Boudien Moerman;
HRB 36809 (AG Nuernberg)