Add Type::cast

src/types.h

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 166 matching lines @@
 
   Iterator<Map> Classes() {
     if (this->is_bitset()) return Iterator<Map>();
     return Iterator<Map>(this->handle());
   }
   Iterator<v8::internal::Object> Constants() {
     if (this->is_bitset()) return Iterator<v8::internal::Object>();
     return Iterator<v8::internal::Object>(this->handle());
   }
 
+  static Type* cast(v8::internal::Object* object) {
+    Type* t = static_cast<Type*>(object);
+    ASSERT(t->is_bitset() || t->is_class() ||
+           t->is_constant() || t->is_union());
+    return t;
+  }
+
  private:
   // A union is a fixed array containing types. Invariants:
   // - its length is at least 2
   // - at most one field is a bitset, and it must go into index 0
   // - no field is a union
   typedef FixedArray Unioned;
 
   enum {
     kNull = 1 << 0,
     kUndefined = 1 << 1,
@@ skipping 66 matching lines @@
   int GlbBitset();  // greatest lower bound that's a bitset
   bool InUnion(Handle<Unioned> unioned, int current_size);
   int ExtendUnion(Handle<Unioned> unioned, int current_size);
   int ExtendIntersection(
       Handle<Unioned> unioned, Handle<Type> type, int current_size);
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_TYPES_H_