NetBSD-9 on 486DLC? (was Re: NetBSD-9 on 80486?)

I renamed the subject since this may be an issue with the 486DLC, but not 
with 80486 in general.

> Hmm, NetBSD 5.0 is the first release after i386 support was removed:
>
> http://gnats.netbsd.org/36163
>
> Cx486DLC may not fully support i486 instructions. Linux seems to drop
> its support along with i386:
>
> https://lkml.org/lkml/2012/12/11/131

The Cyrix and TI 486DLC support the atomic operations of the Intel 80486, 
according to their datasheets, although I'm not

"The LOCK prefix can be used with the following instructions:
Bit Test Instructions (BTS, BTR, BTC)
Exchange Instructions (XADD, XCHG, CMPXCHG)
One-operand Arithmetic and Logical Instructions
(DEC, INC, NEG, NOT)
Two-operand Arithmetic and Logical Instructions
(ADC, ADD, AND, OR, SBB, SUB, XOR)."

Now I can't help but wonder what else might've changed... I'll keep trying 
different things.

Thanks!
John