using overflow_free_p to simplify pattern

In r14-3582, an "overflow_free_p" interface is added.
The pattern of "(t * 2) / 2" in match.pd can be simplified
by using this interface.

gcc/ChangeLog:

	* match.pd ((t * 2) / 2): Update to use overflow_free_p.

diff --git a/gcc/match.pd b/gcc/match.pd
index a37af05f8730cc7b354f9e84b0292920af13d9ef..ce24957926f4b4a1dbdb7b5ecc891fb4619705b2 100644 (file)
--- a/gcc/match.pd
+++ b/gcc/match.pd
@@ -926,36 +926,12 @@ DEFINE_INT_AND_FLOAT_ROUND_FN (RINT)
    (if (TYPE_OVERFLOW_UNDEFINED (type))
     @0
 #if GIMPLE
-    (with
-     {
-       bool overflowed = true;
-       value_range vr0, vr1;
-       if (INTEGRAL_TYPE_P (type)
-          && get_range_query (cfun)->range_of_expr (vr0, @0)
-          && get_range_query (cfun)->range_of_expr (vr1, @1)
-          && !vr0.varying_p () && !vr0.undefined_p ()
-          && !vr1.varying_p () && !vr1.undefined_p ())
-        {
-          wide_int wmin0 = vr0.lower_bound ();
-          wide_int wmax0 = vr0.upper_bound ();
-          wide_int wmin1 = vr1.lower_bound ();
-          wide_int wmax1 = vr1.upper_bound ();
-          /* If the multiplication can't overflow/wrap around, then
-             it can be optimized too.  */
-          wi::overflow_type min_ovf, max_ovf;
-          wi::mul (wmin0, wmin1, TYPE_SIGN (type), &min_ovf);
-          wi::mul (wmax0, wmax1, TYPE_SIGN (type), &max_ovf);
-          if (min_ovf == wi::OVF_NONE && max_ovf == wi::OVF_NONE)
-            {
-              wi::mul (wmin0, wmax1, TYPE_SIGN (type), &min_ovf);
-              wi::mul (wmax0, wmin1, TYPE_SIGN (type), &max_ovf);
-              if (min_ovf == wi::OVF_NONE && max_ovf == wi::OVF_NONE)
-                overflowed = false;
-            }
-        }
-     }
-    (if (!overflowed)
-     @0))
+    (with {value_range vr0, vr1;}
+     (if (INTEGRAL_TYPE_P (type)
+         && get_range_query (cfun)->range_of_expr (vr0, @0)
+         && get_range_query (cfun)->range_of_expr (vr1, @1)
+         && range_op_handler (MULT_EXPR).overflow_free_p (vr0, vr1))
+      @0))
 #endif
    ))))