New port^2: Renesas RL78

[DJ Delorie]

> > (define_expand "umulqihi3"
> >   [(set (match_operand:HI 0 "register_operand")
> >         (mult:HI (zero_extend:HI (match_operand:QI 1 "register_operand"))
> >                  (zero_extend:HI (match_operand:QI 2 "register_operand"))))]
> >   "0"
> >   ""
> > )
> 
> Just delete it?

No, we actually have that insn.  It's the 0 that needs to be deleted.

> It sure looks like 99% of the *_real and *_virt insn patterns should
> have "*" names so that they don't generate unused expanders.

Turns out it was 100%.

> > #define FAILED
> > #define MAYBE_OK(insn) if (insn_ok_now (insn)) return;
> 
> That non-fallback FAILED probably still ought to be gcc_unreachable.

I added that.