Type handling for special cases and optimization

src/types.cc

 // 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 113 matching lines @@
     if (this->is_class()) {
       map = *this->as_class();
     } else {
       Handle<v8::internal::Object> value = this->as_constant();
       if (value->IsSmi()) return kSmi;
       map = HeapObject::cast(*value)->map();
       if (map->instance_type() == ODDBALL_TYPE) {
         if (value->IsUndefined()) return kUndefined;
         if (value->IsNull()) return kNull;
         if (value->IsTrue() || value->IsFalse()) return kBoolean;
+        if (value->IsTheHole()) return kAny;
       }
     }
     switch (map->instance_type()) {
       case STRING_TYPE:
       case ASCII_STRING_TYPE:
       case CONS_STRING_TYPE:
       case CONS_ASCII_STRING_TYPE:
       case SLICED_STRING_TYPE:
       case SLICED_ASCII_STRING_TYPE:
       case EXTERNAL_STRING_TYPE:
@@ skipping 49 matching lines @@
         // When compiling stub templates, the meta map is used as a place holder
         // for the actual map with which the template is later instantiated.
         // We treat it as a kind of type variable whose upper bound is Any.
         // TODO(rossberg): for caching of CompareNilIC stubs to work correctly,
         // we must exclude Undetectable here. This makes no sense, really,
         // because it means that the template isn't actually parametric.
         // Also, it doesn't apply elsewhere. 8-(
         // We ought to find a cleaner solution for compiling stubs parameterised
         // over type or class variables, esp ones with bounds...
         return kDetectable;
+      case DECLARED_ACCESSOR_INFO_TYPE:
+      case EXECUTABLE_ACCESSOR_INFO_TYPE:
+      case ACCESSOR_PAIR_TYPE:
+        return kInternal;
       default:
         UNREACHABLE();
         return kNone;
     }
   }
 }
 
 
 // Get the largest bitset subsumed by this type.
 int Type::GlbBitset() {
   if (this->is_bitset()) {
     return this->as_bitset();
   } else if (this->is_union()) {
     // All but the first are non-bitsets and thus would yield kNone anyway.
     return union_get(this->as_union(), 0)->GlbBitset();
   } else {
     return kNone;
   }
 }
 
 
 // Check this <= that.
-bool Type::Is(Type* that) {
+bool Type::IsSlowCase(Type* that) {
   // Fast path for bitsets.
   if (that->is_bitset()) {
     return (this->LubBitset() | that->as_bitset()) == that->as_bitset();
   }
 
   if (that->is_class()) {
     return this->is_class() && *this->as_class() == *that->as_class();
   }
   if (that->is_constant()) {
     return this->is_constant() && *this->as_constant() == *that->as_constant();
@@ skipping 229 matching lines @@
 }
 
 
 Type* Type::Optional(Handle<Type> type) {
   return type->is_bitset()
       ? from_bitset(type->as_bitset() | kUndefined)
       : Union(type, Undefined()->handle_via_isolate_of(*type));
 }
 
 } }  // namespace v8::internal