Add ObjectPool tag for external labels. Use LoadExternalLabel for native calls...

runtime/vm/object.h

 // 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.
 
 #ifndef VM_OBJECT_H_
 #define VM_OBJECT_H_
 
 #include "include/dart_api.h"
 #include "platform/assert.h"
 #include "platform/utils.h"
@@ skipping 3537 matching lines @@
 
 
 // ObjectPool contains constants, immediates and addresses embedded in code
 // and deoptimization infos. Each entry has an type-info associated with it
 // which is stored in a typed data array (info_array).
 class ObjectPool : public Object {
  public:
   enum EntryType {
     kTaggedObject,
     kImmediate,
+    kExternalLabel,
   };
 
   struct Entry {
     Entry() : raw_value_(), type_() { }
     explicit Entry(const Object* obj) : obj_(obj), type_(kTaggedObject) { }
     Entry(uword value, EntryType info) : raw_value_(value), type_(info) { }
     union {
       const Object* obj_;
       uword raw_value_;
     };
@@ skipping 4467 matching lines @@
 
 
 RawObject* MegamorphicCache::GetTargetFunction(const Array& array,
                                                intptr_t index) {
   return array.At((index * kEntryLength) + kTargetFunctionIndex);
 }
 
 }  // namespace dart
 
 #endif  // VM_OBJECT_H_