> On Thu, Jan 17, 2002 at 04:07:23PM -0800, Ulrich Drepper wrote:
> > The time is near when we (well, I) well start a drastic move toward
> > generally using thread registers. Even in non-threaded code.
> > This means that unless all architectures get thread registers (or
> > equivalent things like Alpha's special code) we'll have a two class
> > society of platforms where all code written for the platforms without
> > thread register can be run on the other systems, but not vice versa.
> > MIPS: Who feels responsible? Andreas, HJ?
> I don't see there are any registers we can use without breaking ABI.
> On the other hand, can we change the mips kernel to save k0 or k1 for
> user space?
Thank you for posting this to linux-mips, since I'm not sure
that anyone at MIPS is on the GNU_libc_hacker list.
It would, in principle, be possible to save/restore k0
or k1 (but not both) if no other clever solution can be found.
There are other VM OSes that manage to do so for MIPS,
for other outside-the-old-ABI reasons. It does, of course,
add some instructions and some memory traffic to the
low-level exception handling , and we would have to look
at whether we would want to make such a feature standard
or specific to a "thread-ready" kernel build.