>
>
> Even if the offset value could be greater than 13 bits, the bias is
> still useful
> as it gives the window spill/fill code a quick way to see if the
> spill/fill is 32 bit
> or 64 bit (check the low order bit of the %sp, if 0 it is 32 bit, if
> 1, it is 64 bit).
> max
>
While I haven't looked at the nucleus code in a few years, I didn't
think we used the lower bit like that because we're tracking the stack
state / register window state in the %wstate register, which causes
processor to execute different trap table entries according to whether
it's a user, kernel, 32bit, 64bit frame, hence the trap handlers are
specific to the type of pointer they're handling.
Cheers,
Greg
