--- a/graal/com.oracle.max.graal.hotspot/src/com/oracle/max/graal/hotspot/ri/HotSpotRuntime.java	Fri Jan 27 18:16:32 2012 -0800
+++ b/graal/com.oracle.max.graal.hotspot/src/com/oracle/max/graal/hotspot/ri/HotSpotRuntime.java	Fri Jan 27 21:17:33 2012 -0800
@@ -313,13 +313,12 @@
         } else if (n instanceof ArrayHeaderSizeNode) {
             ArrayHeaderSizeNode arrayHeaderSize = (ArrayHeaderSizeNode) n;
             graph.replaceFloating(arrayHeaderSize, ConstantNode.forLong(config.getArrayOffset(arrayHeaderSize.elementKind()), n.graph()));
-        } else if (n instanceof ObjectClassNode) {
-            ObjectClassNode objectClassNode = (ObjectClassNode) n;
+        } else if (n instanceof ReadClassNode) {
+            ReadClassNode objectClassNode = (ReadClassNode) n;
             LocationNode location = LocationNode.create(LocationNode.FINAL_LOCATION, CiKind.Object, config.hubOffset, graph);
-            FloatingReadNode memoryRead = graph.add(new FloatingReadNode(CiKind.Object, objectClassNode.object(), null, location));
-            // TODO (ch) this fails because ObjectClass is only used as an input value
-            //memoryRead.setGuard((GuardNode) tool.createGuard(graph.unique(new NullCheckNode(objectClassNode.object(), false))));
-            graph.replaceFloating(objectClassNode, memoryRead);
+            ReadNode memoryRead = graph.add(new ReadNode(CiKind.Object, objectClassNode.object(), location));
+            memoryRead.setGuard((GuardNode) tool.createGuard(graph.unique(new NullCheckNode(objectClassNode.object(), false))));
+            graph.replaceFixed(objectClassNode, memoryRead);
         }
     }