[Bug tree-optimization/119509] Missed optimization for comparison of division equivalent to right shift

[skrll at netbsd dot org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=119509

--- Comment #6 from Nick Hudson <skrll at netbsd dot org> ---
I attached a patch that works for the test case provided. I'm really not sure I
got it right though.