RFC: s390x: correct core file register layout

[Jim Blandy]

Michael Snyder <msnyder@redhat.com> writes:

> Jim Blandy wrote:
> > 
> > 2003-05-23  Jim Blandy  <jimb@redhat.com>
> > 
> >         * s390-nat.c (supply_gregset, fill_gregset): On the s390x, the
> >         elements of gregset_t are 64 bits each, but access registers
> >         are still 32 bits, so they're packed two per gregset_t
> >         element.  Unpack/pack them properly.
> 
> What sort of comment are you looking for?

Well, lewd ones, in particular.  But given the nature of the patch I
wasn't expecting much along those lines, and would have settled for
"this isn't the way we deal with native targets, idiot, look at
foo-nat.c" and stuff like that.

I take it it's kosher to use CONFIG_ARCH_foo in -nat.c files, right?
I feel icky writing that in these modern gdbarch'ed times.  But as
long as we're getting types like gregset_t from the system headers,
the decision on how registers are laid out within that type is
inevitably a compile-time thing, so it's legitimate to use #ifdefs to
select the appropriate code.  Right?

Ideally, I was hoping someone from IBM would check it for
correctness.  But they don't seem to follow these lists,
unfortunately.