[Bug tree-optimization/81913] [8 Regression] wrong code at -O1

[amker at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81913

--- Comment #5 from amker at gcc dot gnu.org ---
(In reply to Martin Liška from comment #4)
> Started with r249778.

Looks like overflow handling.  Thanks for bisecting.