cleanup alter_subreg; fix simplify_subreg

[Hans-Peter Nilsson]

On Wed, 21 Nov 2001, Kaveh R. Ghazi wrote:
> Jan,
>
> I'm pretty sure your change also broke solaris2 bootstraps.  The sparc
> port has a bunch of calls to alter_subreg and none of them appear to
> have been updated as per your parameter change.  See:
> http://gcc.gnu.org/ml/gcc-bugs/2001-11/msg00519.html

Maybe alter_subreg calls need changing, I don't know.  If it's
not that, then maybe it's because sparc.md uses define_peephole
which was also broken by that patch.  For laughs, try
<URL: http://gcc.gnu.org/ml/gcc-patches/2001-11/msg01407.html >.
It helped a bit on the road for arm-elf, but didn't solve the
build problem.  (Sorry: I see no SPARC here.)

brgds, H-P