Make function lookup in classes thread-safe:

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 296 matching lines @@
 
   // Returns the name that is used to identify an object in the
   // namespace dictionary.
   // Object::DictionaryName() returns String::null(). Only subclasses
   // of Object that need to be entered in the library and library prefix
   // namespaces need to provide an implementation.
   virtual RawString* DictionaryName() const;
 
   bool IsNew() const { return raw()->IsNewObject(); }
   bool IsOld() const { return raw()->IsOldObject(); }
-  bool InVMHeap() const {
 #if defined(DEBUG)
-    if (raw()->IsVMHeapObject()) {
-      Heap* vm_isolate_heap = Dart::vm_isolate()->heap();
-      ASSERT(vm_isolate_heap->Contains(RawObject::ToAddr(raw())));
-    }
-#endif
-    return raw()->IsVMHeapObject();
-  }
+  bool InVMHeap() const;
+#else
+  bool InVMHeap() const { return raw()->IsVMHeapObject(); }
+#endif  // DEBUG
 
   // Print the object on stdout for debugging.
   void Print() const;
 
   bool IsZoneHandle() const {
     return VMHandles::IsZoneHandle(reinterpret_cast<uword>(this));
   }
 
   bool IsReadOnlyHandle() const;
 
@@ skipping 8092 matching lines @@
 
 
 RawObject* MegamorphicCache::GetTargetFunction(const Array& array,
                                                intptr_t index) {
   return array.At((index * kEntryLength) + kTargetFunctionIndex);
 }
 
 }  // namespace dart
 
 #endif  // VM_OBJECT_H_