[Bug middle-end/90693] Missing popcount simplifications

[david.bolvansky at gmail dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=90693

--- Comment #3 from Dávid Bolvanský <david.bolvansky at gmail dot com> ---
I measured it a bit..

(x-1) <u (x & -x) is the fastest variant for me