Cleanup: Replace LoadInstanceFieldInstr with LoadVMFieldInstr.

runtime/vm/flow_graph_optimizer.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/flow_graph_optimizer.h"
 
 #include "vm/bit_vector.h"
 #include "vm/cha.h"
 #include "vm/flow_graph_builder.h"
 #include "vm/hash_map.h"
@@ skipping 596 matching lines @@
         String::Handle(Field::NameFromGetter(call->function_name()));
     const Field& field = Field::Handle(GetField(class_ids[0], field_name));
     ASSERT(!field.IsNull());
 
     if (InstanceCallNeedsClassCheck(call)) {
       AddCheckClass(call, call->ArgumentAt(0)->value()->Copy());
     }
     // Detach environment from the original instruction because it can't
     // deoptimize.
     call->set_env(NULL);
-    LoadInstanceFieldInstr* load =
-        new LoadInstanceFieldInstr(field, call->ArgumentAt(0)->value());
+    LoadVMFieldInstr* load = new LoadVMFieldInstr(
+        call->ArgumentAt(0)->value(),
+        field.Offset(),
+        AbstractType::ZoneHandle(field.type()));
     call->ReplaceWith(load, current_iterator());
     RemovePushArguments(call);
     return true;
   }
 
   // Not an implicit getter.
   MethodRecognizer::Kind recognized_kind =
       MethodRecognizer::RecognizeKind(target);
 
   // VM objects length getter.
@@ skipping 788 matching lines @@
       DirectChainedHashMap<Definition*> child_map(*map);  // Copy map.
       OptimizeRecursive(child, &child_map);
     } else {
       OptimizeRecursive(child, map);  // Reuse map for the last child.
     }
   }
 }
 
 
 }  // namespace dart