[Bug target/71763] powerpc64: ICE due to need for output reload on jump

[segher at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71763

--- Comment #2 from Segher Boessenkool <segher at gcc dot gnu.org> ---
Well.  Here it is using a vector register (v31) as the iterator reg,
which we do not handle.  Should we?  Where does it come from?