[Bug rtl-optimization/78638] [7 regression] test cases gcc.target/powerpc/rlwimi-0.c and rlwimi-2.c fail starting with r243000

[segher at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78638

--- Comment #4 from Segher Boessenkool <segher at gcc dot gnu.org> ---
I have a patch for the rlwimi ones.  The new ones are an actual regression
as well.