Re: [RFA] gdbarch.sh: document REGISTER_SIZE and REGISTER_BYTES

[Michael Snyder <msnyder at redhat dot com>]

Andrew Cagney wrote:
> 
> Michael Snyder wrote:
> >
> > Andrew Cagney wrote:
> >
> > > Given that pseudo-register values are created using a fuction and raw
> > > register data, do they have any storage?
> >
> > Sometimes yes, sometimes no.  A pseudo-register can be just
> > an alias for another register, in which case it can share
> > storage.  But it can also be a computed value, in which case
> > it may have its own storage.  I had one case in which a
> > pseudo-register was the concatenation of two regular
> > registers -- but they weren't consecutive, so I had to
> > give the pseudo its own storage and copy them.
> 
> As far as I can tell, in all these cases that pseudo register could have
> been implemented as a functon.  The only reason I can think of for
> having to allocate storage is to work around warts in the way registers
> are currently implemented.  If the core of GDB only accessed registers
> using read/write methods then the storage problem could go away.

All true, of course.