https://gcc.gnu.org/bugzilla/show_bug.cgi?id=71026
Christophe Lyon <clyon at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |clyon at gcc dot gnu.org
--- Comment #13 from Christophe Lyon <clyon at gcc dot gnu.org> ---
(In reply to Wilco from comment #12)
> It looks the only case left to do is f5:
>
> x * C <= 0.0 -> x <= 0.0 if C >= 1.0
> x * C <= 0.0 -> x < FLT_MIN/C if C < 1.0
Commit r266142 (from #c11) added this to match.pd:
(for cmp (lt le gt ge)
neg_cmp (gt ge lt le)
/* Simplify (x * C1) cmp C2 -> x cmp (C2 / C1), where C1 != 0. */
(simplify
(cmp (mult @0 REAL_CST@1) REAL_CST@2)
(with
{ tree tem = const_binop (RDIV_EXPR, type, @2, @1); }
(if (tem
&& !(REAL_VALUE_ISINF (TREE_REAL_CST (tem))
|| (real_zerop (tem) && !real_zerop (@1))))
(switch
(if (real_less (&dconst0, TREE_REAL_CST_PTR (@1)))
(cmp @0 { tem; }))
(if (real_less (TREE_REAL_CST_PTR (@1), &dconst0))
(neg_cmp @0 { tem; })))))))
Doesn't || (real_zerop (tem) && !real_zerop (@1)) prevent
> x * C <= 0.0 -> x <= 0.0 if C >= 1.0
from happening?
