Macro with same operands is misbehaving

[Frank Ch. Eigler]

Hi -

> If I define the instruction fsgnj.s and followed by fmv.s macro, during
> disassembly `fsgnj.s` is always chosen, although assembly works fine.
> [...]
> I can't find a way to say: `fmv.s` matches for disassembly but only if
> `f1` == `f2` in `fsgnj.s f0, f1, f2`.

I don't know of a way either, at the cgen .cpu level.  But I must ask
... why is this particular disassembly heuristic seem important, given
that those are equivalent?  Anyway, it may be possible to handle at
the disassmembler driver level (in C code) even if .cpu/cgen can't
express it.

- FChE