[Bug middle-end/112382] `(a&b) != a` where a is known to have one known bit set is not optimized to ((~b&a)>>shift) & 1

[pinskia at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112382

--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
(In reply to Richard Biener from comment #1)
> Note ((~b&a)>>shift) & 1 is two more GIMPLE ops than (a&b) != a so I'd
> expect the reverse transform on GIMPLE and maybe target specific expansion
> tweaks (or combine at work).


Right, that is why I put the component as middle-end. Specifically because I
think `(a&b) != a` should be the Canonical form and only expanded either in
isel or expand .