--- a/hotspot/src/share/vm/opto/cfgnode.cpp	Fri Jul 18 09:04:01 2014 +0200
+++ b/hotspot/src/share/vm/opto/cfgnode.cpp	Fri Jul 25 10:06:17 2014 +0200
@@ -108,6 +108,7 @@
 
         rreq++;                 // One more input to Region
       } // Found a region to merge into Region
+      igvn->_worklist.push(r);
       // Clobber pointer to the now dead 'r'
       region->set_req(i, phase->C->top());
     }
@@ -449,6 +450,7 @@
   // Remove TOP or NULL input paths. If only 1 input path remains, this Region
   // degrades to a copy.
   bool add_to_worklist = false;
+  bool modified = false;
   int cnt = 0;                  // Count of values merging
   DEBUG_ONLY( int cnt_orig = req(); ) // Save original inputs count
   int del_it = 0;               // The last input path we delete
@@ -459,6 +461,7 @@
       // Remove useless control copy inputs
       if( n->is_Region() && n->as_Region()->is_copy() ) {
         set_req(i, n->nonnull_req());
+        modified = true;
         i--;
         continue;
       }
@@ -466,12 +469,14 @@
         Node *call = n->in(0);
         if (call->is_Call() && call->as_Call()->entry_point() == OptoRuntime::rethrow_stub()) {
           set_req(i, call->in(0));
+          modified = true;
           i--;
           continue;
         }
       }
       if( phase->type(n) == Type::TOP ) {
         set_req(i, NULL);       // Ignore TOP inputs
+        modified = true;
         i--;
         continue;
       }
@@ -691,7 +696,7 @@
     }
   }
 
-  return NULL;
+  return modified ? this : NULL;
 }