[ic] Use validity cells to protect keyed element stores against object's prototype chain modificati…

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 <memory>
 #include <sstream>
@@ skipping 6135 matching lines @@
     object->set_elements(*new_elements);
   } else {
     object->set_elements(object->map()->GetInitialElements());
   }
 }
 
 
 void JSObject::RequireSlowElements(SeededNumberDictionary* dictionary) {
   if (dictionary->requires_slow_elements()) return;
   dictionary->set_requires_slow_elements();
   // TODO(verwaest): Remove this hack.

[Jakob Kummerow, 2016/11/28 18:48:05]

I think you're addressing this TODO :-)

[Igor Sheludko, 2016/11/28 22:25:54]

Done.

   if (map()->is_prototype_map()) {
-    TypeFeedbackVector::ClearAllKeyedStoreICs(GetIsolate());
+    // If this object is a prototype (the callee will check), invalidate any
+    // prototype chains involving it.
+    InvalidatePrototypeChains(map());
   }
 }
 
 
 Handle<SeededNumberDictionary> JSObject::NormalizeElements(
     Handle<JSObject> object) {
   DCHECK(!object->HasFixedTypedArrayElements());
   Isolate* isolate = object->GetIsolate();
   bool is_arguments = object->HasSloppyArgumentsElements();
   {
@@ skipping 9435 matching lines @@
     }
   } else {
     DCHECK(!object->IsAccessCheckNeeded());
   }
 
   Heap* heap = isolate->heap();
   // Silently ignore the change if value is not a JSObject or null.
   // SpiderMonkey behaves this way.
   if (!value->IsJSReceiver() && !value->IsNull(isolate)) return Just(true);
 
-  bool dictionary_elements_in_chain =
-      object->map()->DictionaryElementsInPrototypeChainOnly();
-
   bool all_extensible = object->map()->is_extensible();
   Handle<JSObject> real_receiver = object;
   if (from_javascript) {
     // Find the first object in the chain whose prototype object is not
     // hidden.
     PrototypeIterator iter(isolate, real_receiver, kStartAtPrototype,
                            PrototypeIterator::END_AT_NON_HIDDEN);
     while (!iter.IsAtEnd()) {
       // Casting to JSObject is fine because hidden prototypes are never
       // JSProxies.
@@ skipping 45 matching lines @@
   // Set the new prototype of the object.
 
   isolate->UpdateArrayProtectorOnSetPrototype(real_receiver);
 
   PrototypeOptimizationMode mode =
       from_javascript ? REGULAR_PROTOTYPE : FAST_PROTOTYPE;
   Handle<Map> new_map = Map::TransitionToPrototype(map, value, mode);
   DCHECK(new_map->prototype() == *value);
   JSObject::MigrateToMap(real_receiver, new_map);
 
-  if (from_javascript && !dictionary_elements_in_chain &&
-      new_map->DictionaryElementsInPrototypeChainOnly()) {
-    // If the prototype chain didn't previously have element callbacks, then
-    // KeyedStoreICs need to be cleared to ensure any that involve this
-    // map go generic.
-    TypeFeedbackVector::ClearAllKeyedStoreICs(isolate);
-  }
-
   heap->ClearInstanceofCache();
   DCHECK(size == object->Size());
   return Just(true);
 }
 
 // static
 void JSObject::SetImmutableProto(Handle<JSObject> object) {
   DCHECK(!object->IsAccessCheckNeeded());  // Never called from JS
   Handle<Map> map(object->map());
 
@@ skipping 1676 matching lines @@
     uint32_t key = NumberToUint32(k);
     if (key < limit) {
       if (value->IsUndefined(isolate)) {
         undefs++;
       } else if (pos > static_cast<uint32_t>(Smi::kMaxValue)) {
         // Adding an entry with the key beyond smi-range requires
         // allocation. Bailout.
         return bailout;
       } else {
         Handle<Object> result = SeededNumberDictionary::AddNumberEntry(
-            new_dict, pos, value, details, object->map()->is_prototype_map());
+            new_dict, pos, value, details, object);
         DCHECK(result.is_identical_to(new_dict));
         USE(result);
         pos++;
       }
     } else if (key > static_cast<uint32_t>(Smi::kMaxValue)) {
       // Adding an entry with the key beyond smi-range requires
       // allocation. Bailout.
       return bailout;
     } else {
       Handle<Object> result = SeededNumberDictionary::AddNumberEntry(
-          new_dict, key, value, details, object->map()->is_prototype_map());
+          new_dict, key, value, details, object);
       DCHECK(result.is_identical_to(new_dict));
       USE(result);
     }
   }
 
   uint32_t result = pos;
   PropertyDetails no_details = PropertyDetails::Empty();
   while (undefs > 0) {
     if (pos > static_cast<uint32_t>(Smi::kMaxValue)) {
       // Adding an entry with the key beyond smi-range requires
       // allocation. Bailout.
       return bailout;
     }
     HandleScope scope(isolate);
     Handle<Object> result = SeededNumberDictionary::AddNumberEntry(
         new_dict, pos, isolate->factory()->undefined_value(), no_details,
-        object->map()->is_prototype_map());
+        object);
     DCHECK(result.is_identical_to(new_dict));
     USE(result);
     pos++;
     undefs--;
   }
 
   object->set_elements(*new_dict);
 
   AllowHeapAllocation allocate_return_value;
   return isolate->factory()->NewNumberFromUint(result);
@@ skipping 751 matching lines @@
     if (!this->IsKey(isolate, k)) continue;
     DCHECK(!IsDeleted(i));
     PropertyDetails details = this->DetailsAt(i);
     if (details.type() == ACCESSOR_CONSTANT) return true;
     PropertyAttributes attr = details.attributes();
     if (attr & ALL_ATTRIBUTES_MASK) return true;
   }
   return false;
 }
 
-void SeededNumberDictionary::UpdateMaxNumberKey(uint32_t key,
-                                                bool used_as_prototype) {
+void SeededNumberDictionary::UpdateMaxNumberKey(
+    uint32_t key, Handle<JSObject> dictionary_holder) {
   DisallowHeapAllocation no_allocation;
   // If the dictionary requires slow elements an element has already
   // been added at a high index.
   if (requires_slow_elements()) return;
   // Check if this index is high enough that we should require slow
   // elements.
   if (key > kRequiresSlowElementsLimit) {
-    if (used_as_prototype) {
-      // TODO(verwaest): Remove this hack.
-      TypeFeedbackVector::ClearAllKeyedStoreICs(GetIsolate());
+    if (!dictionary_holder.is_null()) {
+      dictionary_holder->RequireSlowElements(this);
     }
     set_requires_slow_elements();
     return;
   }
   // Update max key value.
   Object* max_index_object = get(kMaxNumberKeyIndex);
   if (!max_index_object->IsSmi() || max_number_key() < key) {
     FixedArray::set(kMaxNumberKeyIndex,
                     Smi::FromInt(key << kRequiresSlowElementsTagSize));
   }
 }
 
-
 Handle<SeededNumberDictionary> SeededNumberDictionary::AddNumberEntry(
     Handle<SeededNumberDictionary> dictionary, uint32_t key,
-    Handle<Object> value, PropertyDetails details, bool used_as_prototype) {
-  dictionary->UpdateMaxNumberKey(key, used_as_prototype);
+    Handle<Object> value, PropertyDetails details,
+    Handle<JSObject> dictionary_holder) {
+  dictionary->UpdateMaxNumberKey(key, dictionary_holder);
   SLOW_DCHECK(dictionary->FindEntry(key) == kNotFound);
   return Add(dictionary, key, value, details);
 }
 
 
 Handle<UnseededNumberDictionary> UnseededNumberDictionary::AddNumberEntry(
     Handle<UnseededNumberDictionary> dictionary,
     uint32_t key,
     Handle<Object> value) {
   SLOW_DCHECK(dictionary->FindEntry(key) == kNotFound);
   return Add(dictionary, key, value, PropertyDetails::Empty());
 }
 
 Handle<UnseededNumberDictionary> UnseededNumberDictionary::DeleteKey(
     Handle<UnseededNumberDictionary> dictionary, uint32_t key) {
   int entry = dictionary->FindEntry(key);
   if (entry == kNotFound) return dictionary;
 
   Factory* factory = dictionary->GetIsolate()->factory();
   dictionary->SetEntry(entry, factory->the_hole_value(),
                        factory->the_hole_value());
   dictionary->ElementRemoved();
   return dictionary->Shrink(dictionary, key);
 }
 
 Handle<SeededNumberDictionary> SeededNumberDictionary::AtNumberPut(
     Handle<SeededNumberDictionary> dictionary, uint32_t key,
-    Handle<Object> value, bool used_as_prototype) {
-  dictionary->UpdateMaxNumberKey(key, used_as_prototype);
+    Handle<Object> value, Handle<JSObject> dictionary_holder) {
+  dictionary->UpdateMaxNumberKey(key, dictionary_holder);
   return AtPut(dictionary, key, value);
 }
 
 
 Handle<UnseededNumberDictionary> UnseededNumberDictionary::AtNumberPut(
     Handle<UnseededNumberDictionary> dictionary,
     uint32_t key,
     Handle<Object> value) {
   return AtPut(dictionary, key, value);
 }
 
-
 Handle<SeededNumberDictionary> SeededNumberDictionary::Set(
     Handle<SeededNumberDictionary> dictionary, uint32_t key,
-    Handle<Object> value, PropertyDetails details, bool used_as_prototype) {
+    Handle<Object> value, PropertyDetails details,
+    Handle<JSObject> dictionary_holder) {
   int entry = dictionary->FindEntry(key);
   if (entry == kNotFound) {
-    return AddNumberEntry(dictionary, key, value, details, used_as_prototype);
+    return AddNumberEntry(dictionary, key, value, details, dictionary_holder);
   }
   // Preserve enumeration index.
   details = details.set_index(dictionary->DetailsAt(entry).dictionary_index());
   Handle<Object> object_key =
       SeededNumberDictionaryShape::AsHandle(dictionary->GetIsolate(), key);
   dictionary->SetEntry(entry, object_key, value, details);
   return dictionary;
 }
 
 
@@ skipping 2167 matching lines @@
       // depend on this.
       return DICTIONARY_ELEMENTS;
     }
     DCHECK_LE(kind, LAST_ELEMENTS_KIND);
     return kind;
   }
 }
 
 }  // namespace internal
 }  // namespace v8