Index -> Entry and Key -> Index in elements.[cc|h]

src/elements.cc

Index: src/elements.cc
diff --git a/src/elements.cc b/src/elements.cc
index 6395e8fa79b0d958f4d06e6c03b7ac2f76361741..89b292a09338e6ad510ca7e59d95ec731751c8e1 100644
--- a/src/elements.cc
+++ b/src/elements.cc
@@ -123,13 +123,13 @@ ELEMENTS_LIST(ELEMENTS_TRAITS)
 #undef ELEMENTS_TRAITS
 
 
-static bool HasKey(Handle<FixedArray> array, Handle<Object> key_handle) {
+static bool HasIndex(Handle<FixedArray> array, Handle<Object> index_handle) {
   DisallowHeapAllocation no_gc;
-  Object* key = *key_handle;
+  Object* index = *index_handle;
   int len0 = array->length();
   for (int i = 0; i < len0; i++) {
     Object* element = array->get(i);
-    if (key->KeyEquals(element)) return true;
+    if (index->KeyEquals(element)) return true;
   }
   return false;
 }
@@ -542,69 +542,71 @@ class ElementsAccessorBase : public ElementsAccessor {
     ElementsAccessorSubclass::ValidateImpl(holder);
   }
 
-  virtual bool HasElement(Handle<JSObject> holder, uint32_t key,
+  virtual bool HasElement(Handle<JSObject> holder, uint32_t index,
                           Handle<FixedArrayBase> backing_store) final {
-    return ElementsAccessorSubclass::GetIndexForKeyImpl(*holder, *backing_store,
-                                                        key) != kMaxUInt32;
+    return ElementsAccessorSubclass::GetEntryForIndexImpl(
+               *holder, *backing_store, index) != kMaxUInt32;
   }
 
-  virtual Handle<Object> Get(Handle<JSObject> holder, uint32_t key,
+  virtual Handle<Object> Get(Handle<JSObject> holder, uint32_t index,
                              Handle<FixedArrayBase> backing_store) final {
     if (!IsExternalArrayElementsKind(ElementsTraits::Kind) &&
         FLAG_trace_js_array_abuse) {
-      CheckArrayAbuse(holder, "elements read", key);
+      CheckArrayAbuse(holder, "elements read", index);
     }
 
     if (IsExternalArrayElementsKind(ElementsTraits::Kind) &&
         FLAG_trace_external_array_abuse) {
-      CheckArrayAbuse(holder, "external elements read", key);
+      CheckArrayAbuse(holder, "external elements read", index);
     }
 
-    return ElementsAccessorSubclass::GetImpl(holder, key, backing_store);
+    return ElementsAccessorSubclass::GetImpl(holder, index, backing_store);
   }
 
-  static Handle<Object> GetImpl(Handle<JSObject> obj, uint32_t key,
+  static Handle<Object> GetImpl(Handle<JSObject> obj, uint32_t index,
                                 Handle<FixedArrayBase> backing_store) {
-    if (key < ElementsAccessorSubclass::GetCapacityImpl(*obj, *backing_store)) {
-      return BackingStore::get(Handle<BackingStore>::cast(backing_store), key);
+    if (index <
+        ElementsAccessorSubclass::GetCapacityImpl(*obj, *backing_store)) {
+      return BackingStore::get(Handle<BackingStore>::cast(backing_store),
+                               index);
     } else {
       return backing_store->GetIsolate()->factory()->the_hole_value();
     }
   }
 
-  virtual void Set(FixedArrayBase* backing_store, uint32_t key,
+  virtual void Set(FixedArrayBase* backing_store, uint32_t index,
                    Object* value) final {
-    ElementsAccessorSubclass::SetImpl(backing_store, key, value);
+    ElementsAccessorSubclass::SetImpl(backing_store, index, value);
   }
 
-  static void SetImpl(FixedArrayBase* backing_store, uint32_t key,
+  static void SetImpl(FixedArrayBase* backing_store, uint32_t index,
                       Object* value) {
-    BackingStore::cast(backing_store)->SetValue(key, value);
+    BackingStore::cast(backing_store)->SetValue(index, value);
   }
 
   virtual void Reconfigure(Handle<JSObject> object,
-                           Handle<FixedArrayBase> store, uint32_t index,
+                           Handle<FixedArrayBase> store, uint32_t entry,
                            Handle<Object> value,
                            PropertyAttributes attributes) final {
-    ElementsAccessorSubclass::ReconfigureImpl(object, store, index, value,
+    ElementsAccessorSubclass::ReconfigureImpl(object, store, entry, value,
                                               attributes);
   }
 
   static void ReconfigureImpl(Handle<JSObject> object,
-                              Handle<FixedArrayBase> store, uint32_t index,
+                              Handle<FixedArrayBase> store, uint32_t entry,
                               Handle<Object> value,
                               PropertyAttributes attributes) {
     UNREACHABLE();
   }
 
-  virtual void Add(Handle<JSObject> object, uint32_t index,
+  virtual void Add(Handle<JSObject> object, uint32_t entry,
                    Handle<Object> value, PropertyAttributes attributes,
                    uint32_t new_capacity) final {
-    ElementsAccessorSubclass::AddImpl(object, index, value, attributes,
+    ElementsAccessorSubclass::AddImpl(object, entry, value, attributes,
                                       new_capacity);
   }
 
-  static void AddImpl(Handle<JSObject> object, uint32_t index,
+  static void AddImpl(Handle<JSObject> object, uint32_t entry,
                       Handle<Object> value, PropertyAttributes attributes,
                       uint32_t new_capacity) {
     UNREACHABLE();
@@ -678,8 +680,8 @@ class ElementsAccessorBase : public ElementsAccessor {
     ElementsAccessorSubclass::GrowCapacityAndConvertImpl(object, capacity);
   }
 
-  virtual void Delete(Handle<JSObject> obj, uint32_t index) final {
-    ElementsAccessorSubclass::DeleteImpl(obj, index);
+  virtual void Delete(Handle<JSObject> obj, uint32_t entry) final {
+    ElementsAccessorSubclass::DeleteImpl(obj, entry);
   }
 
   static void CopyElementsImpl(FixedArrayBase* from, uint32_t from_start,
@@ -755,10 +757,11 @@ class ElementsAccessorBase : public ElementsAccessor {
     // Compute how many elements are not in other.
     uint32_t extra = 0;
     for (uint32_t y = 0; y < len1; y++) {
-      if (ElementsAccessorSubclass::HasIndexImpl(*from, y)) {
-        uint32_t key = ElementsAccessorSubclass::GetKeyForIndexImpl(*from, y);
+      if (ElementsAccessorSubclass::HasEntryImpl(*from, y)) {
+        uint32_t index =
+            ElementsAccessorSubclass::GetIndexForEntryImpl(*from, y);
         Handle<Object> value =
-            ElementsAccessorSubclass::GetImpl(receiver, key, from);
+            ElementsAccessorSubclass::GetImpl(receiver, index, from);
 
         DCHECK(!value->IsTheHole());
         DCHECK(!value->IsAccessorPair());
@@ -766,7 +769,7 @@ class ElementsAccessorBase : public ElementsAccessor {
         if (filter == FixedArray::NON_SYMBOL_KEYS && value->IsSymbol()) {
           continue;
         }
-        if (!HasKey(to, value)) {
+        if (!HasIndex(to, value)) {
           extra++;
         }
       }
@@ -788,24 +791,25 @@ class ElementsAccessorBase : public ElementsAccessor {
       }
     }
     // Fill in the extra values.
-    uint32_t index = 0;
+    uint32_t entry = 0;
     for (uint32_t y = 0; y < len1; y++) {
-      if (ElementsAccessorSubclass::HasIndexImpl(*from, y)) {
-        uint32_t key = ElementsAccessorSubclass::GetKeyForIndexImpl(*from, y);
+      if (ElementsAccessorSubclass::HasEntryImpl(*from, y)) {
+        uint32_t index =
+            ElementsAccessorSubclass::GetIndexForEntryImpl(*from, y);
         Handle<Object> value =
-            ElementsAccessorSubclass::GetImpl(receiver, key, from);
+            ElementsAccessorSubclass::GetImpl(receiver, index, from);
         DCHECK(!value->IsAccessorPair());
         DCHECK(!value->IsExecutableAccessorInfo());
         if (filter == FixedArray::NON_SYMBOL_KEYS && value->IsSymbol()) {
           continue;
         }
-        if (!value->IsTheHole() && !HasKey(to, value)) {
-          result->set(len0 + index, *value);
-          index++;
+        if (!value->IsTheHole() && !HasIndex(to, value)) {
+          result->set(len0 + entry, *value);
+          entry++;
         }
       }
     }
-    DCHECK(extra == index);
+    DCHECK(extra == entry);
     return result;
   }
 
@@ -818,49 +822,44 @@ class ElementsAccessorBase : public ElementsAccessor {
     return ElementsAccessorSubclass::GetCapacityImpl(holder, backing_store);
   }
 
-  static bool HasIndexImpl(FixedArrayBase* backing_store, uint32_t index) {
+  static bool HasEntryImpl(FixedArrayBase* backing_store, uint32_t entry) {
     return true;
   }
 
-  virtual bool HasIndex(FixedArrayBase* backing_store, uint32_t index) final {
-    return ElementsAccessorSubclass::HasIndexImpl(backing_store, index);
-  }
-
-  static uint32_t GetKeyForIndexImpl(FixedArrayBase* backing_store,
-                                     uint32_t index) {
-    return index;
+  virtual bool HasEntry(FixedArrayBase* backing_store, uint32_t entry) final {
+    return ElementsAccessorSubclass::HasEntryImpl(backing_store, entry);
   }
 
-  virtual uint32_t GetKeyForIndex(FixedArrayBase* backing_store,
-                                  uint32_t index) final {
-    return ElementsAccessorSubclass::GetKeyForIndexImpl(backing_store, index);
+  static uint32_t GetIndexForEntryImpl(FixedArrayBase* backing_store,
+                                       uint32_t entry) {
+    return entry;
   }
 
-  static uint32_t GetIndexForKeyImpl(JSObject* holder,
-                                     FixedArrayBase* backing_store,
-                                     uint32_t key) {
-    return key < ElementsAccessorSubclass::GetCapacityImpl(holder,
-                                                           backing_store) &&
-                   !BackingStore::cast(backing_store)->is_the_hole(key)
-               ? key
+  static uint32_t GetEntryForIndexImpl(JSObject* holder,
+                                       FixedArrayBase* backing_store,
+                                       uint32_t index) {
+    return index < ElementsAccessorSubclass::GetCapacityImpl(holder,
+                                                             backing_store) &&
+                   !BackingStore::cast(backing_store)->is_the_hole(index)
+               ? index
                : kMaxUInt32;
   }
 
-  virtual uint32_t GetIndexForKey(JSObject* holder,
-                                  FixedArrayBase* backing_store,
-                                  uint32_t key) final {
-    return ElementsAccessorSubclass::GetIndexForKeyImpl(holder, backing_store,
-                                                        key);
+  virtual uint32_t GetEntryForIndex(JSObject* holder,
+                                    FixedArrayBase* backing_store,
+                                    uint32_t index) final {
+    return ElementsAccessorSubclass::GetEntryForIndexImpl(holder, backing_store,
+                                                          index);
   }
 
   static PropertyDetails GetDetailsImpl(FixedArrayBase* backing_store,
-                                        uint32_t index) {
+                                        uint32_t entry) {
     return PropertyDetails(NONE, DATA, 0, PropertyCellType::kNoCell);
   }
 
   virtual PropertyDetails GetDetails(FixedArrayBase* backing_store,
-                                     uint32_t index) final {
-    return ElementsAccessorSubclass::GetDetailsImpl(backing_store, index);
+                                     uint32_t entry) final {
+    return ElementsAccessorSubclass::GetDetailsImpl(backing_store, entry);
   }
 
  private:
@@ -890,9 +889,9 @@ class DictionaryElementsAccessor
         // deleted and adjust range accordingly.
         for (int i = 0; i < capacity; i++) {

[Igor Sheludko, 2015/07/07 11:01:42]

i -> entry?

           DisallowHeapAllocation no_gc;
-          Object* key = dict->KeyAt(i);
-          if (key->IsNumber()) {
-            uint32_t number = static_cast<uint32_t>(key->Number());
+          Object* index = dict->KeyAt(i);
+          if (index->IsNumber()) {
+            uint32_t number = static_cast<uint32_t>(index->Number());
             if (length <= number && number < old_length) {
               PropertyDetails details = dict->DetailsAt(i);
               if (!details.IsConfigurable()) length = number + 1;
@@ -910,9 +909,9 @@ class DictionaryElementsAccessor
         int removed_entries = 0;
         Handle<Object> the_hole_value = isolate->factory()->the_hole_value();
         for (int i = 0; i < capacity; i++) {

[Igor Sheludko, 2015/07/07 11:01:42]

i -> entry?

-          Object* key = dict->KeyAt(i);
-          if (key->IsNumber()) {
-            uint32_t number = static_cast<uint32_t>(key->Number());
+          Object* index = dict->KeyAt(i);
+          if (index->IsNumber()) {
+            uint32_t number = static_cast<uint32_t>(index->Number());
             if (length <= number && number < old_length) {
               dict->SetEntry(i, the_hole_value, the_hole_value);
               removed_entries++;
@@ -937,51 +936,52 @@ class DictionaryElementsAccessor
   }
 
 
-  static void DeleteImpl(Handle<JSObject> obj, uint32_t index) {
-    // TODO(verwaest): Remove reliance on key in Shrink.
+  static void DeleteImpl(Handle<JSObject> obj, uint32_t entry) {
+    // TODO(verwaest): Remove reliance on index in Shrink.
     Handle<SeededNumberDictionary> dict(
         SeededNumberDictionary::cast(obj->elements()));
-    uint32_t key = GetKeyForIndexImpl(*dict, index);
-    Handle<Object> result = SeededNumberDictionary::DeleteProperty(dict, index);
+    uint32_t index = GetIndexForEntryImpl(*dict, entry);
+    Handle<Object> result = SeededNumberDictionary::DeleteProperty(dict, entry);
     USE(result);
     DCHECK(result->IsTrue());
-    Handle<FixedArray> new_elements = SeededNumberDictionary::Shrink(dict, key);
+    Handle<FixedArray> new_elements =
+        SeededNumberDictionary::Shrink(dict, index);
     obj->set_elements(*new_elements);
   }
 
-  static Handle<Object> GetImpl(Handle<JSObject> obj, uint32_t key,
+  static Handle<Object> GetImpl(Handle<JSObject> obj, uint32_t index,
                                 Handle<FixedArrayBase> store) {
     Handle<SeededNumberDictionary> backing_store =
         Handle<SeededNumberDictionary>::cast(store);
     Isolate* isolate = backing_store->GetIsolate();
-    int entry = backing_store->FindEntry(key);
+    int entry = backing_store->FindEntry(index);
     if (entry != SeededNumberDictionary::kNotFound) {
       return handle(backing_store->ValueAt(entry), isolate);
     }
     return isolate->factory()->the_hole_value();
   }
 
-  static void SetImpl(FixedArrayBase* store, uint32_t key, Object* value) {
+  static void SetImpl(FixedArrayBase* store, uint32_t index, Object* value) {
     SeededNumberDictionary* dictionary = SeededNumberDictionary::cast(store);
-    int entry = dictionary->FindEntry(key);
+    int entry = dictionary->FindEntry(index);
     DCHECK_NE(SeededNumberDictionary::kNotFound, entry);
     dictionary->ValueAtPut(entry, value);
   }
 
   static void ReconfigureImpl(Handle<JSObject> object,
-                              Handle<FixedArrayBase> store, uint32_t index,
+                              Handle<FixedArrayBase> store, uint32_t entry,
                               Handle<Object> value,
                               PropertyAttributes attributes) {
     SeededNumberDictionary* dictionary = SeededNumberDictionary::cast(*store);
     if (attributes != NONE) dictionary->set_requires_slow_elements();
-    dictionary->ValueAtPut(index, *value);
-    PropertyDetails details = dictionary->DetailsAt(index);
+    dictionary->ValueAtPut(entry, *value);
+    PropertyDetails details = dictionary->DetailsAt(entry);
     details = PropertyDetails(attributes, DATA, details.dictionary_index(),
                               PropertyCellType::kNoCell);
-    dictionary->DetailsAtPut(index, details);
+    dictionary->DetailsAtPut(entry, details);
   }
 
-  static void AddImpl(Handle<JSObject> object, uint32_t index,
+  static void AddImpl(Handle<JSObject> object, uint32_t entry,
                       Handle<Object> value, PropertyAttributes attributes,
                       uint32_t new_capacity) {
     PropertyDetails details(attributes, DATA, 0, PropertyCellType::kNoCell);
@@ -990,41 +990,41 @@ class DictionaryElementsAccessor
             ? JSObject::NormalizeElements(object)
             : handle(SeededNumberDictionary::cast(object->elements()));
     Handle<SeededNumberDictionary> new_dictionary =
-        SeededNumberDictionary::AddNumberEntry(dictionary, index, value,
+        SeededNumberDictionary::AddNumberEntry(dictionary, entry, value,
                                                details);
     if (attributes != NONE) new_dictionary->set_requires_slow_elements();
     if (dictionary.is_identical_to(new_dictionary)) return;
     object->set_elements(*new_dictionary);
   }
 
-  static bool HasIndexImpl(FixedArrayBase* store, uint32_t index) {
+  static bool HasEntryImpl(FixedArrayBase* store, uint32_t entry) {
     DisallowHeapAllocation no_gc;
     SeededNumberDictionary* dict = SeededNumberDictionary::cast(store);
-    Object* key = dict->KeyAt(index);
-    return !key->IsTheHole();
+    Object* index = dict->KeyAt(entry);
+    return !index->IsTheHole();
   }
 
-  static uint32_t GetKeyForIndexImpl(FixedArrayBase* store, uint32_t index) {
+  static uint32_t GetIndexForEntryImpl(FixedArrayBase* store, uint32_t entry) {
     DisallowHeapAllocation no_gc;
     SeededNumberDictionary* dict = SeededNumberDictionary::cast(store);
     uint32_t result = 0;
-    CHECK(dict->KeyAt(index)->ToArrayIndex(&result));
+    CHECK(dict->KeyAt(entry)->ToArrayIndex(&result));
     return result;
   }
 
-  static uint32_t GetIndexForKeyImpl(JSObject* holder, FixedArrayBase* store,
-                                     uint32_t key) {
+  static uint32_t GetEntryForIndexImpl(JSObject* holder, FixedArrayBase* store,
+                                       uint32_t index) {
     DisallowHeapAllocation no_gc;
     SeededNumberDictionary* dict = SeededNumberDictionary::cast(store);
-    int entry = dict->FindEntry(key);
+    int entry = dict->FindEntry(index);
     return entry == SeededNumberDictionary::kNotFound
                ? kMaxUInt32
                : static_cast<uint32_t>(entry);
   }
 
   static PropertyDetails GetDetailsImpl(FixedArrayBase* backing_store,
-                                        uint32_t index) {
-    return SeededNumberDictionary::cast(backing_store)->DetailsAt(index);
+                                        uint32_t entry) {
+    return SeededNumberDictionary::cast(backing_store)->DetailsAt(entry);
   }
 };
 
@@ -1041,13 +1041,13 @@ class FastElementsAccessor
 
   typedef typename KindTraits::BackingStore BackingStore;
 
-  static void DeleteCommon(Handle<JSObject> obj, uint32_t index,
+  static void DeleteCommon(Handle<JSObject> obj, uint32_t entry,
                            Handle<FixedArrayBase> store) {
     DCHECK(obj->HasFastSmiOrObjectElements() ||
            obj->HasFastDoubleElements() ||
            obj->HasFastArgumentsElements());
     Handle<BackingStore> backing_store = Handle<BackingStore>::cast(store);
-    backing_store->set_the_hole(index);
+    backing_store->set_the_hole(entry);
 
     // TODO(verwaest): Move this out of elements.cc.
     // If an old space backing store is larger than a certain size and
@@ -1063,8 +1063,8 @@ class FastElementsAccessor
     } else {
       length = static_cast<uint32_t>(store->length());
     }
-    if ((index > 0 && backing_store->is_the_hole(index - 1)) ||
-        (index + 1 < length && backing_store->is_the_hole(index + 1))) {
+    if ((entry > 0 && backing_store->is_the_hole(entry - 1)) ||
+        (entry + 1 < length && backing_store->is_the_hole(entry + 1))) {
       int num_used = 0;
       for (int i = 0; i < backing_store->length(); ++i) {
         if (!backing_store->is_the_hole(i)) ++num_used;
@@ -1078,17 +1078,17 @@ class FastElementsAccessor
   }
 
   static void ReconfigureImpl(Handle<JSObject> object,
-                              Handle<FixedArrayBase> store, uint32_t index,
+                              Handle<FixedArrayBase> store, uint32_t entry,
                               Handle<Object> value,
                               PropertyAttributes attributes) {
     Handle<SeededNumberDictionary> dictionary =
         JSObject::NormalizeElements(object);
-    index = dictionary->FindEntry(index);
-    DictionaryElementsAccessor::ReconfigureImpl(object, dictionary, index,
+    entry = dictionary->FindEntry(entry);
+    DictionaryElementsAccessor::ReconfigureImpl(object, dictionary, entry,
                                                 value, attributes);
   }
 
-  static void AddImpl(Handle<JSObject> object, uint32_t index,
+  static void AddImpl(Handle<JSObject> object, uint32_t entry,
                       Handle<Object> value, PropertyAttributes attributes,
                       uint32_t new_capacity) {
     DCHECK_EQ(NONE, attributes);
@@ -1110,10 +1110,10 @@ class FastElementsAccessor
         JSObject::EnsureWritableFastElements(object);
       }
     }
-    FastElementsAccessorSubclass::SetImpl(object->elements(), index, *value);
+    FastElementsAccessorSubclass::SetImpl(object->elements(), entry, *value);
   }
 
-  static void DeleteImpl(Handle<JSObject> obj, uint32_t index) {
+  static void DeleteImpl(Handle<JSObject> obj, uint32_t entry) {
     ElementsKind kind = KindTraits::Kind;
     if (IsFastPackedElementsKind(kind)) {
       JSObject::TransitionElementsKind(obj, GetHoleyElementsKind(kind));
@@ -1121,11 +1121,11 @@ class FastElementsAccessor
     if (IsFastSmiOrObjectElementsKind(KindTraits::Kind)) {
       JSObject::EnsureWritableFastElements(obj);
     }
-    DeleteCommon(obj, index, handle(obj->elements()));
+    DeleteCommon(obj, entry, handle(obj->elements()));
   }
 
-  static bool HasIndexImpl(FixedArrayBase* backing_store, uint32_t index) {
-    return !BackingStore::cast(backing_store)->is_the_hole(index);
+  static bool HasEntryImpl(FixedArrayBase* backing_store, uint32_t entry) {
+    return !BackingStore::cast(backing_store)->is_the_hole(entry);
   }
 
   static void ValidateContents(Handle<JSObject> holder, int length) {
@@ -1342,17 +1342,18 @@ class TypedElementsAccessor
   typedef typename ElementsKindTraits<Kind>::BackingStore BackingStore;
   typedef TypedElementsAccessor<Kind> AccessorClass;
 
-  static Handle<Object> GetImpl(Handle<JSObject> obj, uint32_t key,
+  static Handle<Object> GetImpl(Handle<JSObject> obj, uint32_t index,
                                 Handle<FixedArrayBase> backing_store) {
-    if (key < AccessorClass::GetCapacityImpl(*obj, *backing_store)) {
-      return BackingStore::get(Handle<BackingStore>::cast(backing_store), key);
+    if (index < AccessorClass::GetCapacityImpl(*obj, *backing_store)) {
+      return BackingStore::get(Handle<BackingStore>::cast(backing_store),
+                               index);
     } else {
       return backing_store->GetIsolate()->factory()->undefined_value();
     }
   }
 
   static PropertyDetails GetDetailsImpl(FixedArrayBase* backing_store,
-                                        uint32_t index) {
+                                        uint32_t entry) {
     return PropertyDetails(DONT_DELETE, DATA, 0, PropertyCellType::kNoCell);
   }
 
@@ -1362,15 +1363,15 @@ class TypedElementsAccessor
     UNREACHABLE();
   }
 
-  static void DeleteImpl(Handle<JSObject> obj, uint32_t index) {
+  static void DeleteImpl(Handle<JSObject> obj, uint32_t entry) {
     UNREACHABLE();
   }
 
-  static uint32_t GetIndexForKeyImpl(JSObject* holder,
-                                     FixedArrayBase* backing_store,
-                                     uint32_t key) {
-    return key < AccessorClass::GetCapacityImpl(holder, backing_store)
-               ? key
+  static uint32_t GetEntryForIndexImpl(JSObject* holder,
+                                       FixedArrayBase* backing_store,
+                                       uint32_t index) {
+    return index < AccessorClass::GetCapacityImpl(holder, backing_store)
+               ? index
                : kMaxUInt32;
   }
 
@@ -1409,30 +1410,30 @@ class SloppyArgumentsElementsAccessor
       : ElementsAccessorBase<SloppyArgumentsElementsAccessorSubclass,
                              KindTraits>(name) {}
 
-  static Handle<Object> GetImpl(Handle<JSObject> obj, uint32_t key,
+  static Handle<Object> GetImpl(Handle<JSObject> obj, uint32_t index,
                                 Handle<FixedArrayBase> parameters) {
     Isolate* isolate = obj->GetIsolate();
     Handle<FixedArray> parameter_map = Handle<FixedArray>::cast(parameters);
-    Handle<Object> probe(GetParameterMapArg(*parameter_map, key), isolate);
+    Handle<Object> probe(GetParameterMapArg(*parameter_map, index), isolate);
     if (!probe->IsTheHole()) {
       DisallowHeapAllocation no_gc;
       Context* context = Context::cast(parameter_map->get(0));
-      int context_index = Handle<Smi>::cast(probe)->value();
-      DCHECK(!context->get(context_index)->IsTheHole());
-      return handle(context->get(context_index), isolate);
+      int context_entry = Handle<Smi>::cast(probe)->value();
+      DCHECK(!context->get(context_entry)->IsTheHole());
+      return handle(context->get(context_entry), isolate);
     } else {
       // Object is not mapped, defer to the arguments.
       Handle<FixedArray> arguments(FixedArray::cast(parameter_map->get(1)),
                                    isolate);
-      Handle<Object> result = ArgumentsAccessor::GetImpl(obj, key, arguments);
+      Handle<Object> result = ArgumentsAccessor::GetImpl(obj, index, arguments);
       // Elements of the arguments object in slow mode might be slow aliases.
       if (result->IsAliasedArgumentsEntry()) {
         DisallowHeapAllocation no_gc;
         AliasedArgumentsEntry* entry = AliasedArgumentsEntry::cast(*result);
         Context* context = Context::cast(parameter_map->get(0));
-        int context_index = entry->aliased_context_slot();
-        DCHECK(!context->get(context_index)->IsTheHole());
-        return handle(context->get(context_index), isolate);
+        int context_entry = entry->aliased_context_slot();
+        DCHECK(!context->get(context_entry)->IsTheHole());
+        return handle(context->get(context_entry), isolate);
       } else {
         return result;
       }
@@ -1444,17 +1445,17 @@ class SloppyArgumentsElementsAccessor
     UNREACHABLE();
   }
 
-  static void SetImpl(FixedArrayBase* store, uint32_t key, Object* value) {
+  static void SetImpl(FixedArrayBase* store, uint32_t index, Object* value) {
     FixedArray* parameter_map = FixedArray::cast(store);
-    Object* probe = GetParameterMapArg(parameter_map, key);
+    Object* probe = GetParameterMapArg(parameter_map, index);
     if (!probe->IsTheHole()) {
       Context* context = Context::cast(parameter_map->get(0));
-      int context_index = Smi::cast(probe)->value();
-      DCHECK(!context->get(context_index)->IsTheHole());
-      context->set(context_index, value);
+      int context_entry = Smi::cast(probe)->value();
+      DCHECK(!context->get(context_entry)->IsTheHole());
+      context->set(context_entry, value);
     } else {
       FixedArray* arguments = FixedArray::cast(parameter_map->get(1));
-      ArgumentsAccessor::SetImpl(arguments, key, value);
+      ArgumentsAccessor::SetImpl(arguments, index, value);
     }
   }
 
@@ -1472,70 +1473,71 @@ class SloppyArgumentsElementsAccessor
            ArgumentsAccessor::GetCapacityImpl(holder, arguments);
   }
 
-  static bool HasIndexImpl(FixedArrayBase* parameters, uint32_t index) {
+  static bool HasEntryImpl(FixedArrayBase* parameters, uint32_t entry) {
     FixedArray* parameter_map = FixedArray::cast(parameters);
     uint32_t length = parameter_map->length() - 2;
-    if (index < length) {
-      return !GetParameterMapArg(parameter_map, index)->IsTheHole();
+    if (entry < length) {
+      return !GetParameterMapArg(parameter_map, entry)->IsTheHole();
     }
 
     FixedArrayBase* arguments = FixedArrayBase::cast(parameter_map->get(1));
-    return ArgumentsAccessor::HasIndexImpl(arguments, index - length);
+    return ArgumentsAccessor::HasEntryImpl(arguments, entry - length);
   }
 
-  static uint32_t GetKeyForIndexImpl(FixedArrayBase* parameters,
-                                     uint32_t index) {
+  static uint32_t GetIndexForEntryImpl(FixedArrayBase* parameters,
+                                       uint32_t entry) {
     FixedArray* parameter_map = FixedArray::cast(parameters);
     uint32_t length = parameter_map->length() - 2;
-    if (index < length) return index;
+    if (entry < length) return entry;
 
     FixedArray* arguments = FixedArray::cast(parameter_map->get(1));
-    return ArgumentsAccessor::GetKeyForIndexImpl(arguments, index - length);
+    return ArgumentsAccessor::GetIndexForEntryImpl(arguments, entry - length);
   }
 
-  static uint32_t GetIndexForKeyImpl(JSObject* holder,
-                                     FixedArrayBase* parameters, uint32_t key) {
+  static uint32_t GetEntryForIndexImpl(JSObject* holder,
+                                       FixedArrayBase* parameters,
+                                       uint32_t index) {
     FixedArray* parameter_map = FixedArray::cast(parameters);
-    Object* probe = GetParameterMapArg(parameter_map, key);
-    if (!probe->IsTheHole()) return key;
+    Object* probe = GetParameterMapArg(parameter_map, index);
+    if (!probe->IsTheHole()) return index;
 
     FixedArray* arguments = FixedArray::cast(parameter_map->get(1));
-    uint32_t index =
-        ArgumentsAccessor::GetIndexForKeyImpl(holder, arguments, key);
-    if (index == kMaxUInt32) return index;
-    return (parameter_map->length() - 2) + index;
+    uint32_t entry =
+        ArgumentsAccessor::GetEntryForIndexImpl(holder, arguments, index);
+    if (entry == kMaxUInt32) return entry;
+    return (parameter_map->length() - 2) + entry;
   }
 
   static PropertyDetails GetDetailsImpl(FixedArrayBase* parameters,
-                                        uint32_t index) {
+                                        uint32_t entry) {
     FixedArray* parameter_map = FixedArray::cast(parameters);
     uint32_t length = parameter_map->length() - 2;
-    if (index < length) {
+    if (entry < length) {
       return PropertyDetails(NONE, DATA, 0, PropertyCellType::kNoCell);
     }
-    index -= length;
+    entry -= length;
     FixedArray* arguments = FixedArray::cast(parameter_map->get(1));
-    return ArgumentsAccessor::GetDetailsImpl(arguments, index);
+    return ArgumentsAccessor::GetDetailsImpl(arguments, entry);
   }
 
-  static Object* GetParameterMapArg(FixedArray* parameter_map, uint32_t key) {
+  static Object* GetParameterMapArg(FixedArray* parameter_map, uint32_t index) {
     uint32_t length = parameter_map->length() - 2;
-    return key < length
-               ? parameter_map->get(key + 2)
+    return index < length
+               ? parameter_map->get(index + 2)
                : Object::cast(parameter_map->GetHeap()->the_hole_value());
   }
 
-  static void DeleteImpl(Handle<JSObject> obj, uint32_t index) {
+  static void DeleteImpl(Handle<JSObject> obj, uint32_t entry) {
     FixedArray* parameter_map = FixedArray::cast(obj->elements());
     uint32_t length = static_cast<uint32_t>(parameter_map->length()) - 2;
-    if (index < length) {
+    if (entry < length) {
       // TODO(kmillikin): We could check if this was the last aliased
       // parameter, and revert to normal elements in that case.  That
       // would enable GC of the context.
-      parameter_map->set_the_hole(index + 2);
+      parameter_map->set_the_hole(entry + 2);
     } else {
       SloppyArgumentsElementsAccessorSubclass::DeleteFromArguments(
-          obj, index - length);
+          obj, entry - length);
     }
   }
 };
@@ -1551,20 +1553,21 @@ class SlowSloppyArgumentsElementsAccessor
             SlowSloppyArgumentsElementsAccessor, DictionaryElementsAccessor,
             ElementsKindTraits<SLOW_SLOPPY_ARGUMENTS_ELEMENTS> >(name) {}
 
-  static void DeleteFromArguments(Handle<JSObject> obj, uint32_t index) {
+  static void DeleteFromArguments(Handle<JSObject> obj, uint32_t entry) {
     Handle<FixedArray> parameter_map(FixedArray::cast(obj->elements()));
     Handle<SeededNumberDictionary> dict(
         SeededNumberDictionary::cast(parameter_map->get(1)));
-    // TODO(verwaest): Remove reliance on key in Shrink.
-    uint32_t key = GetKeyForIndexImpl(*dict, index);
-    Handle<Object> result = SeededNumberDictionary::DeleteProperty(dict, index);
+    // TODO(verwaest): Remove reliance on index in Shrink.
+    uint32_t index = GetIndexForEntryImpl(*dict, entry);
+    Handle<Object> result = SeededNumberDictionary::DeleteProperty(dict, entry);
     USE(result);
     DCHECK(result->IsTrue());
-    Handle<FixedArray> new_elements = SeededNumberDictionary::Shrink(dict, key);
+    Handle<FixedArray> new_elements =
+        SeededNumberDictionary::Shrink(dict, index);
     parameter_map->set(1, *new_elements);
   }
 
-  static void AddImpl(Handle<JSObject> object, uint32_t key,
+  static void AddImpl(Handle<JSObject> object, uint32_t index,
                       Handle<Object> value, PropertyAttributes attributes,
                       uint32_t new_capacity) {
     Handle<FixedArray> parameter_map(FixedArray::cast(object->elements()));
@@ -1576,7 +1579,8 @@ class SlowSloppyArgumentsElementsAccessor
             : JSObject::NormalizeElements(object);
     PropertyDetails details(attributes, DATA, 0, PropertyCellType::kNoCell);
     Handle<SeededNumberDictionary> new_dictionary =
-        SeededNumberDictionary::AddNumberEntry(dictionary, key, value, details);
+        SeededNumberDictionary::AddNumberEntry(dictionary, index, value,
+                                               details);
     if (attributes != NONE) new_dictionary->set_requires_slow_elements();
     if (*dictionary != *new_dictionary) {
       FixedArray::cast(object->elements())->set(1, *new_dictionary);
@@ -1584,38 +1588,38 @@ class SlowSloppyArgumentsElementsAccessor
   }
 
   static void ReconfigureImpl(Handle<JSObject> object,
-                              Handle<FixedArrayBase> store, uint32_t index,
+                              Handle<FixedArrayBase> store, uint32_t entry,
                               Handle<Object> value,
                               PropertyAttributes attributes) {
     Handle<FixedArray> parameter_map = Handle<FixedArray>::cast(store);
     uint32_t length = parameter_map->length() - 2;
-    if (index < length) {
-      Object* probe = parameter_map->get(index + 2);
+    if (entry < length) {
+      Object* probe = parameter_map->get(entry + 2);
       DCHECK(!probe->IsTheHole());
       Context* context = Context::cast(parameter_map->get(0));
-      int context_index = Smi::cast(probe)->value();
-      DCHECK(!context->get(context_index)->IsTheHole());
-      context->set(context_index, *value);
+      int context_entry = Smi::cast(probe)->value();
+      DCHECK(!context->get(context_entry)->IsTheHole());
+      context->set(context_entry, *value);
 
       // Redefining attributes of an aliased element destroys fast aliasing.
-      parameter_map->set_the_hole(index + 2);
+      parameter_map->set_the_hole(entry + 2);
       // For elements that are still writable we re-establish slow aliasing.
       if ((attributes & READ_ONLY) == 0) {
         Isolate* isolate = store->GetIsolate();
-        value = isolate->factory()->NewAliasedArgumentsEntry(context_index);
+        value = isolate->factory()->NewAliasedArgumentsEntry(context_entry);
       }
 
       PropertyDetails details(attributes, DATA, 0, PropertyCellType::kNoCell);
       Handle<SeededNumberDictionary> arguments(
           SeededNumberDictionary::cast(parameter_map->get(1)));
-      arguments = SeededNumberDictionary::AddNumberEntry(arguments, index,
+      arguments = SeededNumberDictionary::AddNumberEntry(arguments, entry,
                                                          value, details);
       parameter_map->set(1, *arguments);
     } else {
       Handle<FixedArrayBase> arguments(
           FixedArrayBase::cast(parameter_map->get(1)));
       DictionaryElementsAccessor::ReconfigureImpl(
-          object, arguments, index - length, value, attributes);
+          object, arguments, entry - length, value, attributes);
     }
   }
 };
@@ -1632,13 +1636,13 @@ class FastSloppyArgumentsElementsAccessor
             FastHoleyObjectElementsAccessor,
             ElementsKindTraits<FAST_SLOPPY_ARGUMENTS_ELEMENTS> >(name) {}
 
-  static void DeleteFromArguments(Handle<JSObject> obj, uint32_t index) {
+  static void DeleteFromArguments(Handle<JSObject> obj, uint32_t entry) {
     FixedArray* parameter_map = FixedArray::cast(obj->elements());
     Handle<FixedArray> arguments(FixedArray::cast(parameter_map->get(1)));
-    FastHoleyObjectElementsAccessor::DeleteCommon(obj, index, arguments);
+    FastHoleyObjectElementsAccessor::DeleteCommon(obj, entry, arguments);
   }
 
-  static void AddImpl(Handle<JSObject> object, uint32_t key,
+  static void AddImpl(Handle<JSObject> object, uint32_t index,
                       Handle<Object> value, PropertyAttributes attributes,
                       uint32_t new_capacity) {
     DCHECK_EQ(NONE, attributes);
@@ -1649,21 +1653,21 @@ class FastSloppyArgumentsElementsAccessor
         static_cast<uint32_t>(old_elements->length()) < new_capacity) {
       GrowCapacityAndConvertImpl(object, new_capacity);
     }
-    SetImpl(object->elements(), key, *value);
+    SetImpl(object->elements(), index, *value);
   }
 
   static void ReconfigureImpl(Handle<JSObject> object,
-                              Handle<FixedArrayBase> store, uint32_t index,
+                              Handle<FixedArrayBase> store, uint32_t entry,
                               Handle<Object> value,
                               PropertyAttributes attributes) {
     Handle<SeededNumberDictionary> dictionary =
         JSObject::NormalizeElements(object);
     FixedArray::cast(*store)->set(1, *dictionary);
     uint32_t length = static_cast<uint32_t>(store->length()) - 2;
-    if (index >= length) {
-      index = dictionary->FindEntry(index - length) + length;
+    if (entry >= length) {
+      entry = dictionary->FindEntry(entry - length) + length;
     }
-    SlowSloppyArgumentsElementsAccessor::ReconfigureImpl(object, store, index,
+    SlowSloppyArgumentsElementsAccessor::ReconfigureImpl(object, store, entry,
                                                          value, attributes);
   }
 
@@ -1749,7 +1753,7 @@ void ElementsAccessorBase<ElementsAccessorSubclass, ElementsKindTraits>::
 }  // namespace
 
 
-void CheckArrayAbuse(Handle<JSObject> obj, const char* op, uint32_t key,
+void CheckArrayAbuse(Handle<JSObject> obj, const char* op, uint32_t index,
                      bool allow_appending) {
   DisallowHeapAllocation no_allocation;
   Object* raw_length = NULL;
@@ -1768,10 +1772,10 @@ void CheckArrayAbuse(Handle<JSObject> obj, const char* op, uint32_t key,
       int32_t int32_length = DoubleToInt32(n);
       uint32_t compare_length = static_cast<uint32_t>(int32_length);
       if (allow_appending) compare_length++;
-      if (key >= compare_length) {
+      if (index >= compare_length) {
         PrintF("[OOB %s %s (%s length = %d, element accessed = %d) in ",
                elements_type, op, elements_type, static_cast<int>(int32_length),
-               static_cast<int>(key));
+               static_cast<int>(index));
         TraceTopFrame(obj->GetIsolate());
         PrintF("]\n");
       }
@@ -1844,8 +1848,8 @@ MaybeHandle<Object> ArrayConstructInitializeElements(Handle<JSArray> array,
     case FAST_HOLEY_SMI_ELEMENTS:
     case FAST_SMI_ELEMENTS: {
       Handle<FixedArray> smi_elms = Handle<FixedArray>::cast(elms);
-      for (int index = 0; index < number_of_elements; index++) {
-        smi_elms->set(index, (*args)[index], SKIP_WRITE_BARRIER);
+      for (int entry = 0; entry < number_of_elements; entry++) {
+        smi_elms->set(entry, (*args)[entry], SKIP_WRITE_BARRIER);
       }
       break;
     }
@@ -1854,8 +1858,8 @@ MaybeHandle<Object> ArrayConstructInitializeElements(Handle<JSArray> array,
       DisallowHeapAllocation no_gc;
       WriteBarrierMode mode = elms->GetWriteBarrierMode(no_gc);
       Handle<FixedArray> object_elms = Handle<FixedArray>::cast(elms);
-      for (int index = 0; index < number_of_elements; index++) {
-        object_elms->set(index, (*args)[index], mode);
+      for (int entry = 0; entry < number_of_elements; entry++) {
+        object_elms->set(entry, (*args)[entry], mode);
       }
       break;
     }
@@ -1863,8 +1867,8 @@ MaybeHandle<Object> ArrayConstructInitializeElements(Handle<JSArray> array,
     case FAST_DOUBLE_ELEMENTS: {
       Handle<FixedDoubleArray> double_elms =
           Handle<FixedDoubleArray>::cast(elms);
-      for (int index = 0; index < number_of_elements; index++) {
-        double_elms->set(index, (*args)[index]->Number());
+      for (int entry = 0; entry < number_of_elements; entry++) {
+        double_elms->set(entry, (*args)[entry]->Number());
       }
       break;
     }