Re: [kvm-unit-tests PATCH v3 7/7] s390x: Add test for STFLE interpretive execution (format-0)

Heiko Carstens
2024-09-03T10:46:30Z

On Mon, Sep 02, 2024 at 04:24:53PM +0200, Nina Schoetterl-Glausch wrote:
> On Tue, 2024-08-27 at 16:08 +0200, Nico Boehr wrote:
> > Quoting Nina Schoetterl-Glausch (2024-06-20 16:17:00)
> >
> > And: is long displacement even appropriate here?
> >
> > The cast also is hard to understand. Since this is not super high
> > performance code, do we just want to clobber memory so this gets a bit
> > easier to understand?
> >
> > > + [len] "+RT"(res[0])
> >
> > Same question about RT as above.
>
> Long, but providing a short displacement should be fine too.
> Not sure if there is any benefit to letting the compiler choose.

There are some older gcc compilers around which fail to compile if you
specify T for long displacement, but the compiler sees that a short
displacement would work. So please specify RT to avoid such compile
bugs.

See https://gcc.gnu.org/git/?p=gcc.git;a=commit;h=3e4be43f69da