Re: new gdb arch routine FRAME_UNCHANGED

[Andrew Cagney <ac131313@ges.redhat.com>]

> The patch below defines a new gdbarch routine called FRAME_UNCHANGED.
> This is needed for gdb/ia64 because the ia64 architecture has two
> separate stack pointers (one for memory stack and one for register stack).
> Because of the two stacks, it's not possible to look just at the frame
> pointer and PC to determine whether a frame changed.
> 
> If the patch looks OK, I'd appreciate if someone could apply it.
> 
> Note: the patch below doesn't include the ia64 version of
> FRAME_UNCHANGED.  It is part of a larger update to add unwind library
> support to gdb/ia64 and I'll submit that separately.  So, for now, the
> patch is effectively a no-op for all platforms.
> 
> Also, it will be necessary to re-generate gdbarch.[ch] after applying
> the patch.

Just to follow this up.  The frame_id code has been committed.  I think 
this has the potential of affecting the way you did your patch.  For 
instance, it could compare frame_id's for either sameness or more 
inner_than.

Andrew