Verify dominators in early-out calculate_dominance_info

2015-06-22  Tom de Vries  <tom@codesourcery.com>

	* dominance.c (calculate_dominance_info): Verify dominators if
	early-out.

From-SVN: r224744

gcc/ChangeLog

+2015-06-22  Tom de Vries  <tom@codesourcery.com>
+
+	* dominance.c (calculate_dominance_info): Verify dominators if
+	early-out.
+
 2015-06-22  Marek Polacek  <polacek@redhat.com>
 
 	* match.pd ((x ^ y) ^ (x | y) -> x & y,

gcc/dominance.c

@@ -646,7 +646,12 @@ calculate_dominance_info (enum cdi_direction dir)
   bool reverse = (dir == CDI_POST_DOMINATORS) ? true : false;
 
   if (dom_computed[dir_index] == DOM_OK)
-    return;
+    {
+#if ENABLE_CHECKING
+      verify_dominators (CDI_DOMINATORS);
+#endif
+      return;
+    }
 
   timevar_push (TV_DOMINANCE);
   if (!dom_info_available_p (dir))