only for exceptions.
While adding this to exception_save and exception_restore, it was hard
to find a good place to put the instructions. The code sequence was
sufficiently arbitrarily ordered that the density was low (roughly 67%).
No explicit bundling was used.
Thus, I rewrote the functions to optimize for density (close to 80% now),
and added explicit bundles and nop instructions. The immediate operand
on the nop instruction has been incremented with each instance, to make
debugging a bit easier when looking at recurring patterns. Redundant
stops have been removed as much as possible. Future optimizations can
focus more on performance. A well-placed lfetch can make all the
difference here!
Also, the FRAME_Fxx defines in frame.h were mostly bogus. FRAME_F10 to
FRAME_F15 were copied from FRAME_F9 and still had the same index. We
don't use them yet, so nothing was broken.
* Fixes to the signal delivery code. Not quite right yet.
I would have preferred to wait until I have signal delivery actually
working but the current kernel in CVS doesn't build.
kernel backing store.
* Implement syscalls via break instructions.
* Fix backing store copying in cpu_fork() so that the child gets the right
register values.
This thing is actually starting to work now. This set of changes takes me
up to the second execve (the one which runs the first shell). Next stop
single-user mode :-).
not work on any real hardware (or fully work on any simulator). Much more
needs to happen before this is actually functional but its nice to see
the FreeBSD copyright message appear in the ia64 simulator.
