Introduce LookupIterator::Restart() and use it

src/objects.cc

 // Copyright 2013 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 6036 matching lines @@
   Isolate* isolate = it->isolate();
   // == OrdinaryDefineOwnProperty (O, P, Desc) ==
   // 1. Let current be O.[[GetOwnProperty]](P).
   // 2. ReturnIfAbrupt(current).
   PropertyDescriptor current;
   if (!GetOwnPropertyDescriptor(it, &current) &&
       isolate->has_pending_exception()) {
     return false;
   }
   // 3. Let extensible be the value of the [[Extensible]] internal slot of O.
-  Handle<JSObject> o = Handle<JSObject>::cast(it->GetReceiver());
-  bool extensible = JSObject::IsExtensible(o);
+  Handle<JSObject> object = Handle<JSObject>::cast(it->GetReceiver());
+  bool extensible = JSObject::IsExtensible(object);
 
   bool desc_is_data_descriptor = PropertyDescriptor::IsDataDescriptor(desc);
   bool desc_is_accessor_descriptor =
       PropertyDescriptor::IsAccessorDescriptor(desc);
   bool desc_is_generic_descriptor =
       PropertyDescriptor::IsGenericDescriptor(desc);
 
   // == ValidateAndApplyPropertyDescriptor (O, P, extensible, Desc, current) ==
   // 2. If current is undefined, then
   if (current.is_empty()) {
     // 2a. If extensible is false, return false.
     if (!extensible) {
       if (should_throw == THROW_ON_ERROR) {
         isolate->Throw(*isolate->factory()->NewTypeError(
             MessageTemplate::kDefineDisallowed, it->GetName()));
       }
       return false;
     }
-    // We have to use a fresh LookupIterator to handle interceptors properly.
-    LookupIterator lookup_for_store =
-        it->IsElement() ? LookupIterator(isolate, it->GetReceiver(),
-                                         it->index(), LookupIterator::HIDDEN)
-                        : LookupIterator(it->GetReceiver(), it->name(),
-                                         LookupIterator::HIDDEN);
+    // We have to reset the LookupIterator to handle interceptors properly.
+    Map* map = Handle<HeapObject>::cast(object)->map();
+    if ((it->IsElement() && map->has_indexed_interceptor()) ||
+        (!it->IsElement() && map->has_named_interceptor())) {
+      it->Restart();
+    }
 
     // 2c. If IsGenericDescriptor(Desc) or IsDataDescriptor(Desc) is true, then:
     // (This is equivalent to !IsAccessorDescriptor(desc).)
     DCHECK((desc_is_generic_descriptor || desc_is_data_descriptor) ==
            !desc_is_accessor_descriptor);
     if (!desc_is_accessor_descriptor) {
       // 2c i. If O is not undefined, create an own data property named P of
       // object O whose [[Value]], [[Writable]], [[Enumerable]] and
       // [[Configurable]] attribute values are described by Desc. If the value
       // of an attribute field of Desc is absent, the attribute of the newly
       // created property is set to its default value.
-      if (!o->IsUndefined()) {
+      if (!object->IsUndefined()) {
         if (!desc->has_writable()) desc->set_writable(false);
         if (!desc->has_enumerable()) desc->set_enumerable(false);
         if (!desc->has_configurable()) desc->set_configurable(false);
         Handle<Object> value(
             desc->has_value()
                 ? desc->value()
                 : Handle<Object>::cast(isolate->factory()->undefined_value()));
         MaybeHandle<Object> result =
             JSObject::DefineOwnPropertyIgnoreAttributes(
-                &lookup_for_store, value, desc->ToAttributes(),
-                JSObject::DONT_FORCE_FIELD);
+                it, value, desc->ToAttributes(), JSObject::DONT_FORCE_FIELD);
         if (result.is_null()) return false;
       }
     } else {
       // 2d. Else Desc must be an accessor Property Descriptor,
       DCHECK(desc_is_accessor_descriptor);
       // 2d i. If O is not undefined, create an own accessor property named P
       // of object O whose [[Get]], [[Set]], [[Enumerable]] and
       // [[Configurable]] attribute values are described by Desc. If the value
       // of an attribute field of Desc is absent, the attribute of the newly
       // created property is set to its default value.
-      if (!o->IsUndefined()) {
+      if (!object->IsUndefined()) {
         if (!desc->has_enumerable()) desc->set_enumerable(false);
         if (!desc->has_configurable()) desc->set_configurable(false);
         Handle<Object> getter(
             desc->has_get()
                 ? desc->get()
                 : Handle<Object>::cast(isolate->factory()->undefined_value()));
         Handle<Object> setter(
             desc->has_set()
                 ? desc->set()
                 : Handle<Object>::cast(isolate->factory()->undefined_value()));
-        MaybeHandle<Object> result = JSObject::DefineAccessor(
-            &lookup_for_store, getter, setter, desc->ToAttributes());
+        MaybeHandle<Object> result =
+            JSObject::DefineAccessor(it, getter, setter, desc->ToAttributes());
         if (result.is_null()) return false;
       }
     }
     // 2e. Return true.
     return true;
   }
   // 3. Return true, if every field in Desc is absent.
   // 4. Return true, if every field in Desc also occurs in current and the
   // value of every field in Desc is the same value as the corresponding field
   // in current when compared using the SameValue algorithm.
@@ skipping 67 matching lines @@
     }
 
     // 8. Else if IsDataDescriptor(current) and IsDataDescriptor(Desc) are both
     // true, then:
   } else if (current_is_data_descriptor && desc_is_data_descriptor) {
     // 8a. If the [[Configurable]] field of current is false, then:
     if (!current.configurable()) {
       // [Strong mode] Disallow changing writable -> readonly for
       // non-configurable properties.
       if (current.writable() && desc->has_writable() && !desc->writable() &&
-          o->map()->is_strong()) {
+          object->map()->is_strong()) {
         if (should_throw == THROW_ON_ERROR) {
           isolate->Throw(*isolate->factory()->NewTypeError(
-              MessageTemplate::kStrongRedefineDisallowed, o, it->GetName()));
+              MessageTemplate::kStrongRedefineDisallowed, object,
+              it->GetName()));
         }
         return false;
       }
       // 8a i. Return false, if the [[Writable]] field of current is false and
       // the [[Writable]] field of Desc is true.
       if (!current.writable() && desc->has_writable() && desc->writable()) {
         if (should_throw == THROW_ON_ERROR) {
           isolate->Throw(*isolate->factory()->NewTypeError(
               MessageTemplate::kRedefineDisallowed, it->GetName()));
         }
@@ skipping 34 matching lines @@
         if (should_throw == THROW_ON_ERROR) {
           isolate->Throw(*isolate->factory()->NewTypeError(
               MessageTemplate::kRedefineDisallowed, it->GetName()));
         }
         return false;
       }
     }
   }
 
   // 10. If O is not undefined, then:
-  if (!o->IsUndefined()) {
+  if (!object->IsUndefined()) {
     // 10a. For each field of Desc that is present, set the corresponding
     // attribute of the property named P of object O to the value of the field.
     PropertyAttributes attrs = NONE;
 
     if (desc->has_enumerable()) {
       attrs = static_cast<PropertyAttributes>(
           attrs | (desc->enumerable() ? NONE : DONT_ENUM));
     } else {
       attrs = static_cast<PropertyAttributes>(
           attrs | (current.enumerable() ? NONE : DONT_ENUM));
@@ skipping 11547 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