https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89536
--- Comment #5 from Eric Botcazou <ebotcazou at gcc dot gnu.org> ---
> I wonder if we shouldn't do:
> --- gcc/tree-ssa-dom.c.jj 2019-02-26 14:13:08.296824100 +0100
> +++ gcc/tree-ssa-dom.c 2019-02-28 15:46:52.285495060 +0100
> @@ -346,6 +346,9 @@ edge_info::derive_equivalences (tree nam
> boolean types with precision > 1. */
> if (code == BIT_NOT_EXPR
> && TREE_CODE (rhs) == SSA_NAME
> + && (TREE_CODE (TREE_TYPE (rhs)) == BOOLEAN_TYPE
> + || (INTEGRAL_TYPE_P (TREE_TYPE (rhs))
> + && TYPE_PRECISION (TREE_TYPE (rhs)) == 1))
> && ssa_name_has_boolean_range (rhs))
> {
> if (integer_zerop (value))
>
> because while ssa_name_has_boolean_range returns true for both the case
> where the type is BOOLEAN_TYPE and where the type is integral with precision
> 1 (and unsigned), we do not want to do this if the type has larger precision
> and just the value has [0, 1] value range.
> Perhaps we just should do the checks and not call ssa_name_has_boolean_range
> here.
There is very likely the same issue in the BIT_AND_EXPR case then.
