Factor out super-class and interface array subtype checks into a stub.

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 471 matching lines @@
 
   RawLibrary* library() const { return raw_ptr()->library_; }
   void set_library(const Library& value) const;
 
   // The type parameters are specified as an array of TypeParameter.
   RawTypeArguments* type_parameters() const {
       return raw_ptr()->type_parameters_;
   }
   void set_type_parameters(const TypeArguments& value) const;
   intptr_t NumTypeParameters() const;
+  static intptr_t type_parameters_offset() {
+    return OFFSET_OF(RawClass, type_parameters_);
+  }
 
   // Type parameter bounds (implicitly Dynamic if not explicitly specified) as
   // an array of AbstractType.
   RawTypeArguments* type_parameter_bounds() const {
     return raw_ptr()->type_parameter_bounds_;
   }
   void set_type_parameter_bounds(const TypeArguments& value) const;
 
   // Return a TypeParameter if the type_name is a type parameter of this class.
   // Return null otherwise.
@@ skipping 110 matching lines @@
   void InsertCanonicalConstant(intptr_t index, const Instance& constant) const;
 
   static intptr_t InstanceSize() {
     return RoundedAllocationSize(sizeof(RawClass));
   }
 
   bool is_interface() const {
     return raw_ptr()->is_interface_;
   }
   void set_is_interface() const;
+  static intptr_t is_interface_offset() {
+    return OFFSET_OF(RawClass, is_interface_);
+  }
 
   bool is_finalized() const {
     return raw_ptr()->class_state_ == RawClass::kFinalized;
   }
   void set_is_finalized() const;
 
   bool is_prefinalized() const {
     return raw_ptr()->class_state_ == RawClass::kPreFinalized;
   }
 
@@ skipping 3276 matching lines @@
 }
 
 
 intptr_t Stackmap::SizeInBits() const {
   return (Smi::Value(raw_ptr()->bitmap_size_in_bytes_) * kBitsPerByte);
 }
 
 }  // namespace dart
 
 #endif  // VM_OBJECT_H_