bjh21@netbsd.org said:
>  Having random undocumented #ifdefs all over the place (without even a
> defopt, usually) is one of the things that makes modifying the arm32
> sources painful. 

OK, I'll defopt this one, but I think we should use a generic name that 
can be used in other MD files.  Any suggestions?  My ideas would be

UNWIND_LOOPS
NO_ICACHE
SLOW_BRANCHES

with probably a mild preference for the first of those.