re PR bootstrap/80978 (LTO/PGO bootstrap broken by r248863)

	PR bootstrap/80978
	* tree-cfg.c (execute_fixup_cfg): Fix condition on when to rescale
	profile.

From-SVN: r248915

gcc/ChangeLog

 2017-06-06  Jan Hubicka  <hubicka@ucw.cz>
 
+	PR bootstrap/80978
+	* tree-cfg.c (execute_fixup_cfg): Fix condition on when to rescale
+	profile.
+
+2017-06-06  Jan Hubicka  <hubicka@ucw.cz>
+
 	* shrink-wrap.c (handle_simple_exit): Update profile.
 	(try_shrink_wrapping): Upate profile.
 

gcc/tree-cfg.c

@@ -9077,7 +9077,9 @@ execute_fixup_cfg (void)
   cgraph_node *node = cgraph_node::get (current_function_decl);
   profile_count num = node->count;
   profile_count den = ENTRY_BLOCK_PTR_FOR_FN (cfun)->count;
-  bool scale = num.initialized_p () && den.initialized_p () && !(num == den);
+  bool scale = num.initialized_p ()
+	       && (den > 0 || num == profile_count::zero ())
+	       && !(num == den);
 
   if (scale)
     {