Mark null and undefined as undetectable, and use it to handle abstract equality comparison in the g…

src/objects.cc

 // Copyright 2015 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/objects.h"
 
 #include <cmath>
 #include <iomanip>
 #include <sstream>
 
@@ skipping 394 matching lines @@
     if (!that->IsSimd128Value()) return false;
     return Simd128Value::cast(this)->Equals(Simd128Value::cast(that));
   }
   return this == that;
 }
 
 
 // static
 Handle<String> Object::TypeOf(Isolate* isolate, Handle<Object> object) {
   if (object->IsNumber()) return isolate->factory()->number_string();
-  if (object->IsUndefined() || object->IsUndetectableObject()) {
+  if (object->IsOddball()) return handle(Oddball::cast(*object)->type_of());
+  if (object->IsUndetectableObject()) {
     return isolate->factory()->undefined_string();
   }
-  if (object->IsBoolean()) return isolate->factory()->boolean_string();
   if (object->IsString()) return isolate->factory()->string_string();
   if (object->IsSymbol()) return isolate->factory()->symbol_string();
   if (object->IsString()) return isolate->factory()->string_string();
 #define SIMD128_TYPE(TYPE, Type, type, lane_count, lane_type) \
   if (object->Is##Type()) return isolate->factory()->type##_string();
   SIMD128_TYPES(SIMD128_TYPE)
 #undef SIMD128_TYPE
   if (object->IsCallable()) return isolate->factory()->function_string();
   return isolate->factory()->object_string();
 }
@@ skipping 19494 matching lines @@
   if (cell->value() != *new_value) {
     cell->set_value(*new_value);
     Isolate* isolate = cell->GetIsolate();
     cell->dependent_code()->DeoptimizeDependentCodeGroup(
         isolate, DependentCode::kPropertyCellChangedGroup);
   }
 }
 
 }  // namespace internal
 }  // namespace v8