[Bug tree-optimization/66299] more optimize oppotunity

[pinskia at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=66299

--- Comment #1 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
1<<x == 2 can be transformed into x == 1 and that seems like it is not being
done.

Related to bug 15350.