[PATCH] ipa-sra: Consider the first parameter of methods safe to dereference

[Richard Biener]

On Wed, Dec 14, 2022 at 4:20 PM Jan Hubicka via Gcc-patches
<gcc-patches@gcc.gnu.org> wrote:
>
> > Hi,
> >
> > Honza requested this after reviewing the patch that taught IPA-SRA
> > that REFERENCE_TYPEs are always non-NULL that the pass also handles
> > the first parameters of methods, this pointers, in the same way.  So
> > this patch does that.
> >
> > The patch is undergoing bootstrap and testing on an x86_64-linux right
> > now.  OK if it passes?
> >
> > Thanks,
> >
> > Martin
> >
> >
> > gcc/ChangeLog:
> >
> > 2022-12-14  Martin Jambor  <mjambor@suse.cz>
> >
> >       * ipa-sra.cc (create_parameter_descriptors): Consider the first
> >       parameter of a method safe to dereference.
> >
> > gcc/testsuite/ChangeLog:
> >
> > 2022-12-14  Martin Jambor  <mjambor@suse.cz>
> >
> >       * g++.dg/ipa/ipa-sra-6.C: New test.
>
> OK,

Are you sure that's safe?  The docs for METHOD_TYPE doesn't say 'this'
is the first parameter nor does it say methods cannot be invoked for a
nullptr object.

Do frontends other than C++ create METHOD_TYPE functions?  Grep
shows uses in ada and objective C at least.

> thanks a lot!
> Honza