https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82439
--- Comment #6 from Marc Glisse <glisse at gcc dot gnu.org> ---
(In reply to Andrew Pinski from comment #1)
> "(x | y) == x" is simpler than "(y & ~x) == 0" on the tree level. 2 gimple
> vs 3.
We do indeed tend to use the number of stmts to chose canonical forms on
gimple, but that's not the only possible criterion. The second form uses x only
once instead of twice ("simpler" as in: fewer uses), and there are a number of
gimple optimizations that are gated by single_use, which arguably gives some
advantage to the second form. (I am not saying we should pick the second form,
just that the choice may not be completely obvious)
