Re: [9fans] 6a bug

[Charles Forsyth <charles.forsyth@gmail.com>]

I'd replied, but "Reply"'s default is never right (either way).
It's as you say, and the reason it worked in the kernel is
that KZERO was a different value, which did satisfy the hardware's constraint.

On some of the older RISC machines, the loader might generate impossible
constants into a register itself, but that relied on defining a global REGTMP,
which was fine on a 32-ish register machine (you hardly ever need that many)
but not so good on the amd64 where the original registers are strange and
in short supply, and the new registers have a penalty, and there are only 16
in all.