Implement class hierarchy analysis in the VM.

runtime/vm/raw_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_RAW_OBJECT_H_
 #define VM_RAW_OBJECT_H_
 
 #include "platform/assert.h"
 #include "vm/globals.h"
 #include "vm/token.h"
@@ skipping 390 matching lines @@
 
  private:
   RAW_HEAP_OBJECT_IMPLEMENTATION(Class);
 
   RawObject** from() { return reinterpret_cast<RawObject**>(&ptr()->name_); }
   RawString* name_;
   RawArray* functions_;
   RawArray* fields_;
   RawGrowableObjectArray* closure_functions_;  // Local functions and literals.
   RawArray* interfaces_;  // Array of AbstractType.
+  RawGrowableObjectArray* direct_subclasses_;  // Array of Class.
   RawScript* script_;
   RawLibrary* library_;
   RawTypeArguments* type_parameters_;  // Array of TypeParameter.
   RawType* super_type_;
   RawObject* factory_class_;  // UnresolvedClass (until finalization) or Class.
   RawFunction* signature_function_;  // Associated function for signature class.
   RawArray* constants_;  // Canonicalized values of this class.
   RawArray* canonical_types_;  // Canonicalized types of this class.
   RawCode* allocation_stub_;  // Stub code for allocation of instances.
   RawObject** to() {
@@ skipping 1164 matching lines @@
          kExternalUint64ArrayCid == kByteArrayCid + 18 &&
          kExternalFloat32ArrayCid == kByteArrayCid + 19 &&
          kExternalFloat64ArrayCid == kByteArrayCid + 20 &&
          kStacktraceCid == kByteArrayCid + 21);
   return (index >= kByteArrayCid && index <= kExternalFloat64ArrayCid);
 }
 
 }  // namespace dart
 
 #endif  // VM_RAW_OBJECT_H_