[Bug testsuite/106516] New test case gcc.dg/pr104992.c fails on power 10

["linkw at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106516

--- Comment #7 from Kewen Lin <linkw at gcc dot gnu.org> ---
(In reply to Peter Bergner from comment #6)
> (In reply to Kewen Lin from comment #5)
> > Created attachment 53492 [details]
> > Adjust pr104992.c with vect_int_mod
> > 
> > > So it sounds like we want a generic target supports test that is true on
> > > targets (like power10) with a vector mod and key off that.  Any ideas how we
> > > can do that?
> > 
> > Add one effective target vect_int_mod for it, one quick grepping for i386
> > and aarch64 shows they don't have such support.
> 
> Heh, I was thinking of whether we could actually test whether an actual
> target supported it, but given no other arches seem to be failing this test
> case other than P10, I guess that will work. :-)

Thanks for the clarification, I guess that's doable. In this patch, I mainly
followed the existing practice vect_int_mult (there are also some similar
effective targets describing target vector support capability). With this way,
if some other arches support this in future, target owners need to add their
own conditions.