[Bug tree-optimization/81503] Wrong code at -O2

[glisse at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81503

--- Comment #1 from Marc Glisse <glisse at gcc dot gnu.org> ---
Looks like SLSR does an overflow-unsafe transformation, then VRP2 takes
advantage of it. Maybe.