Optimize getField by caching a closure generated from a specialized function kind.

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 1868 matching lines @@
   }
 
   // Returns true if this function represents an static initializer function.
   bool IsStaticInitializerFunction() const {
     return kind() == RawFunction::kStaticInitializer;
   }
 
   // Returns true if this function represents a (possibly implicit) closure
   // function.
   bool IsClosureFunction() const {
-    return kind() == RawFunction::kClosureFunction;
+    return (kind() == RawFunction::kClosureFunction) ||
+           (kind() == RawFunction::kGetFieldClosure) ||
+           (kind() == RawFunction::kSetFieldClosure);
   }
 
   // Returns true if this function represents an implicit closure function.
   bool IsImplicitClosureFunction() const;
 
   // Returns true if this function represents a non implicit closure function.
   bool IsNonImplicitClosureFunction() const {
     return IsClosureFunction() && !IsImplicitClosureFunction();
   }
 
@@ skipping 4757 matching lines @@
 
 
 RawObject* MegamorphicCache::GetTargetFunction(const Array& array,
                                                intptr_t index) {
   return array.At((index * kEntryLength) + kTargetFunctionIndex);
 }
 
 }  // namespace dart
 
 #endif  // VM_OBJECT_H_