https://gcc.gnu.org/bugzilla/show_bug.cgi?id=96779
--- Comment #3 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
(In reply to Andrew Pinski from comment #2)
> This is simple, I will take.
> (for cmp (eq ne)
> (simplify
> (cmp:c @0 (negate @0))
> (if (ANY_INTEGRAL_TYPE_P (TREE_TYPE (@0)))
> (cmp:c @0 { build_zero_cst (TREE_TYPE(@0)); })))))
>
> Should be enough.
But it is wrong for wrapping types.
For wrapping types:
-a == a -> (a << 1) == a or (a + a) == 0
But this is worse on targets which have a pattern for -a CMP a (hint aarch64).
So for wrapping types keep the -a == a is the best I think.
