ifcvt/crossjump patch: Fix PR 42496, 21803

[Eric Botcazou]

> Can we all agree that the problem can be viewed as either cfg
> manipulations or insn movement and that what we're really arguing about
> is which is the most appropriate way to view the problem?

Yes.

> If so, then we really need to determine which implementation is the
> easiest to understand, implement & maintain.

Yes, and I think only experiments can give a definitive answer.  That's all 
what I requested from Bernd.

-- 
Eric Botcazou