[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

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

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

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
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             Target|                            |x86_64-*-*

--- Comment #1 from Richard Biener <rguenth at gcc dot gnu.org> ---
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).

Mangling the testcases to expect CSE with the (a&b) != a would be the thing
to test on GIMPLE (maybe simply expect ICF to happen?!)