[Isolates] Avoid dereferencing Isolate::Current() to check oddball identities...

src/objects-inl.h

 // Copyright 2006-2008 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 504 matching lines @@
 }
 
 
 bool Object::IsProxy() {
   return Object::IsHeapObject()
     && HeapObject::cast(this)->map()->instance_type() == PROXY_TYPE;
 }
 
 
 bool Object::IsBoolean() {
-  return IsTrue() || IsFalse();
+  return IsOddball() &&
+      ((Oddball::cast(this)->kind() & Oddball::kNotBooleanMask) == 0);
 }
 
 
 bool Object::IsJSArray() {
   return Object::IsHeapObject()
     && HeapObject::cast(this)->map()->instance_type() == JS_ARRAY_TYPE;
 }
 
 
 bool Object::IsJSRegExp() {
@@ skipping 117 matching lines @@
 #define MAKE_STRUCT_PREDICATE(NAME, Name, name)                  \
   bool Object::Is##Name() {                                      \
     return Object::IsHeapObject()                                \
       && HeapObject::cast(this)->map()->instance_type() == NAME##_TYPE; \
   }
   STRUCT_LIST(MAKE_STRUCT_PREDICATE)
 #undef MAKE_STRUCT_PREDICATE
 
 
 bool Object::IsUndefined() {
-  return this == HEAP->undefined_value();
+  return IsOddball() && Oddball::cast(this)->kind() == Oddball::kUndefined;
 }
 
 
 bool Object::IsTheHole() {
-  return this == HEAP->the_hole_value();
+  return IsOddball() && Oddball::cast(this)->kind() == Oddball::kTheHole;
 }
 
 
 bool Object::IsNull() {
-  return this == HEAP->null_value();
+  return IsOddball() && Oddball::cast(this)->kind() == Oddball::kNull;
 }
 
 
 bool Object::IsTrue() {
-  return this == HEAP->true_value();
+  return IsOddball() && Oddball::cast(this)->kind() == Oddball::kTrue;
 }
 
 
 bool Object::IsFalse() {
-  return this == HEAP->false_value();
+  return IsOddball() && Oddball::cast(this)->kind() == Oddball::kFalse;
 }
 
 
 double Object::Number() {
   ASSERT(IsNumber());
   return IsSmi()
     ? static_cast<double>(reinterpret_cast<Smi*>(this)->value())
     : reinterpret_cast<HeapNumber*>(this)->value();
 }
 
 
-
 Object* Object::ToSmi() {
   if (IsSmi()) return this;
   if (IsHeapNumber()) {
     double value = HeapNumber::cast(this)->value();
     int int_value = FastD2I(value);
     if (value == FastI2D(int_value) && Smi::IsValid(int_value)) {
       return Smi::FromInt(int_value);
     }
   }
   return Failure::Exception();
@@ skipping 490 matching lines @@
   set_map(Map::cast(obj));
   initialize_elements();
   return this;
 }
 
 
 ACCESSORS(Oddball, to_string, String, kToStringOffset)
 ACCESSORS(Oddball, to_number, Object, kToNumberOffset)
 
 
+byte Oddball::kind() {
+  return READ_BYTE_FIELD(this, kKindOffset);
+}
+
+
+void Oddball::set_kind(byte value) {
+  WRITE_BYTE_FIELD(this, kKindOffset, value);
+}
+
+
 Object* JSGlobalPropertyCell::value() {
   return READ_FIELD(this, kValueOffset);
 }
 
 
 void JSGlobalPropertyCell::set_value(Object* val, WriteBarrierMode ignored) {
   // The write barrier is not used for global property cells.
   ASSERT(!val->IsJSGlobalPropertyCell());
   WRITE_FIELD(this, kValueOffset, val);
 }
@@ skipping 1492 matching lines @@
   return Context::cast(READ_FIELD(this, kContextOffset));
 }
 
 
 Object* JSFunction::unchecked_context() {
   return READ_FIELD(this, kContextOffset);
 }
 
 
 void JSFunction::set_context(Object* value) {
-  ASSERT(value == HEAP->undefined_value() || value->IsContext());
+  ASSERT(value->IsUndefined() || value->IsContext());
   WRITE_FIELD(this, kContextOffset, value);
   WRITE_BARRIER(this, kContextOffset);
 }
 
 ACCESSORS(JSFunction, prototype_or_initial_map, Object,
           kPrototypeOrInitialMapOffset)
 
 
 Map* JSFunction::initial_map() {
   return Map::cast(prototype_or_initial_map());
@@ skipping 610 matching lines @@
 #undef WRITE_INT_FIELD
 #undef READ_SHORT_FIELD
 #undef WRITE_SHORT_FIELD
 #undef READ_BYTE_FIELD
 #undef WRITE_BYTE_FIELD
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_OBJECTS_INL_H_