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Re: [PATCH] Add flag to control straight-line strength reduction
On Wed, 2012-07-18 at 11:01 +0200, Richard Guenther wrote:
> On Wed, 18 Jul 2012, Steven Bosscher wrote:
>
> > On Wed, Jul 18, 2012 at 9:59 AM, Richard Guenther <rguenther@suse.de> wrote:
> > > On Tue, 17 Jul 2012, William J. Schmidt wrote:
> > >
> > >> I overlooked adding a pass-control flag for strength reduction, added
> > >> here. I named it -ftree-slsr for consistency with other -ftree- flags,
> > >> but could change it to -fgimple-slsr if you prefer that for a pass named
> > >> gimple-ssa-...
> > >>
> > >> Bootstrapped and tested on powerpc-unknown-linux-gnu with no new
> > >> regressions. Ok for trunk?
> > >
> > > The switch needs documentation in doc/invoke.texi. Other than that
> > > it's fine to stick with -ftree-..., even that exposes details to our
> > > users that are not necessary (RTL passes didn't have -frtl-... either).
> > > So in the end, why not re-use -fstrength-reduce that is already available
> > > (but stubbed out)?
> >
> > In the past, -fstrength-reduce applied to loop strength reduction in
> > loop.c. I don't think it should be re-used for a completely different
> > code transformation.
>
> Ok. I suppose -ftree-slsr is ok then.
It turns out I was looking at a very old copy of the manual, and the
-ftree... stuff is not as prevalent now as it once was. I'll just go
with -fslsr to be consistent with -fgcse, -fipa-sra, etc.
Thanks for the pointer to doc/invoke.texi -- it appears I also failed to
document -fhoist-adjacent-loads, so I will go ahead and do that as well.
Thanks!
Bill
>
> Thanks,
> Richard.
>