https://gcc.gnu.org/bugzilla/show_bug.cgi?id=111151
Jakub Jelinek <jakub at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |jakub at gcc dot gnu.org
--- Comment #7 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
(In reply to Richard Biener from comment #3)
> @@ -6970,8 +6972,11 @@ extract_muldiv_1 (tree t, tree c, enum tree_code
> code, tree wide_type,
>
> /* MIN (a, b) / 5 -> MIN (a / 5, b / 5) */
> sub_strict_overflow_p = false;
> - if ((t1 = extract_muldiv (op0, c, code, wide_type,
> - &sub_strict_overflow_p)) != 0
> + if ((wide_type
> + ? TYPE_OVERFLOW_UNDEFINED (wide_type)
> + : TYPE_OVERFLOW_UNDEFINED (TREE_TYPE (op0)))
> + && (t1 = extract_muldiv (op0, c, code, wide_type,
> + &sub_strict_overflow_p)) != 0
> && (t2 = extract_muldiv (op1, c, code, wide_type,
> &sub_strict_overflow_p)) != 0)
> {
Isn't it fine as is for unsigned divisions and modulos?
I'd think the only problem is TYPE_OVERFLOW_WRAPS code == MULT_EXPR or
!TYPE_UNSIGNED && TYPE_OVERFLOW_WRAPS division/modulo (say -fwrapv MIN (a, b) /
-1
-> MAX (a / -1, b / -1) transformation wouldn't be correct for a INT_MIN b 0,
because the first one is INT_MIN / -1 aka. INT_MIN, while the latter is 0
or perhaps TYPE_OVERFLOW_SANITIZED should be punted on as well.
