re PR tree-optimization/81463 (ICE in scale_loop_profile at gcc/cfgloopmanip.c:603)

	PR middle-end/81463
	* cfgloopmanip.c (scale_loop_profile): Watch out for zero frequency
	again.

From-SVN: r250311

gcc/ChangeLog

 2017-07-18  Jan Hubicka  <hubicka@ucw.cz>
 
+	PR middle-end/81463
+	* cfgloopmanip.c (scale_loop_profile): Watch out for zero frequency
+	again.
+
+2017-07-18  Jan Hubicka  <hubicka@ucw.cz>
+
 	PR middle-end/81462
 	* predict.c (set_even_probabilities): Cleanup; do not affect
 	probabilities that are already known.

gcc/cfgloopmanip.c

@@ -591,7 +591,7 @@ scale_loop_profile (struct loop *loop, profile_probability p,
 	      determined = true;
 	    }
 	}
-      if (!determined)
+      if (!determined && loop->header->frequency)
 	{
 	  int freq_in = 0;