[Bug target/81291] [6/7/8 Regression] wrong code with -O2 -fno-rerun-cse-after-loop -fno-tree-ter -fno-tree-vrp -funroll-loops due to improper carry

[segher at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81291

--- Comment #4 from Segher Boessenkool <segher at gcc dot gnu.org> ---
Fixed on trunk.  This may be the same as PR82621, which I'll backport this
week.