Move SetFastDoubleElementsCapacity into GrowCapacityAndConvert

BUG=v8:4137
LOG=n

Review URL: https://codereview.chromium.org/1193343002

Cr-Commit-Position: refs/heads/master@{#29182}

src/elements.cc

@@ -644,10 +644,16 @@ class ElementsAccessorBase : public ElementsAccessor {
   static void SetLengthImpl(Handle<JSArray> array, uint32_t length,
                             Handle<FixedArrayBase> backing_store);
 
-  static void GrowCapacityAndConvert(Handle<JSObject> obj, int capacity) {
+  static void GrowCapacityAndConvertImpl(Handle<JSObject> obj,
+                                         uint32_t capacity) {
     UNIMPLEMENTED();
   }
 
+  virtual void GrowCapacityAndConvert(Handle<JSObject> object,
+                                      uint32_t capacity) final {
+    ElementsAccessorSubclass::GrowCapacityAndConvertImpl(object, capacity);
+  }
+
   virtual void Delete(Handle<JSObject> obj, uint32_t key,
                       LanguageMode language_mode) override = 0;
 
@@ -1031,7 +1037,8 @@ class FastSmiOrObjectElementsAccessor
   }
 
 
-  static void GrowCapacityAndConvert(Handle<JSObject> obj, uint32_t capacity) {
+  static void GrowCapacityAndConvertImpl(Handle<JSObject> obj,
+                                         uint32_t capacity) {
     JSObject::SetFastElementsCapacitySmiMode set_capacity_mode =
         obj->HasFastSmiElements()
             ? JSObject::kAllowSmiElements
@@ -1098,8 +1105,32 @@ class FastDoubleElementsAccessor
       : FastElementsAccessor<FastElementsAccessorSubclass,
                              KindTraits>(name) {}
 
-  static void GrowCapacityAndConvert(Handle<JSObject> obj, uint32_t capacity) {
-    JSObject::SetFastDoubleElementsCapacity(obj, capacity);
+  static void GrowCapacityAndConvertImpl(Handle<JSObject> object,
+                                         uint32_t capacity) {
+    Handle<FixedArrayBase> elements =
+        object->GetIsolate()->factory()->NewFixedDoubleArray(capacity);
+    ElementsKind from_kind = object->GetElementsKind();
+    ElementsKind to_kind = IsHoleyElementsKind(from_kind)
+                               ? FAST_HOLEY_DOUBLE_ELEMENTS
+                               : FAST_DOUBLE_ELEMENTS;
+
+    Handle<Map> new_map = JSObject::GetElementsTransitionMap(object, to_kind);
+
+    Handle<FixedArrayBase> old_elements(object->elements());
+    int packed = kPackedSizeNotKnown;
+    if (IsFastPackedElementsKind(from_kind) && object->IsJSArray()) {
+      packed = Smi::cast(JSArray::cast(*object)->length())->value();
+    }
+    CopyElementsImpl(*old_elements, 0, *elements, from_kind, 0, packed,
+                     ElementsAccessor::kCopyToEndAndInitializeToHole);
+
+    JSObject::SetMapAndElements(object, new_map, elements);
+    JSObject::ValidateElements(object);
+
+    if (FLAG_trace_elements_transitions) {
+      JSObject::PrintElementsTransition(stdout, object, from_kind, old_elements,
+                                        to_kind, elements);
+    }
   }
 
  protected:
@@ -1664,7 +1695,7 @@ void ElementsAccessorBase<ElementsAccessorSubclass, ElementsKindTraits>::
   } else {
     // Check whether the backing store should be expanded.
     capacity = Max(length, JSObject::NewElementsCapacity(capacity));
-    ElementsAccessorSubclass::GrowCapacityAndConvert(array, capacity);
+    ElementsAccessorSubclass::GrowCapacityAndConvertImpl(array, capacity);
   }
 
   array->set_length(Smi::FromInt(length));

src/elements.h

@@ -121,6 +121,9 @@ class ElementsAccessor {
       *from_holder, 0, from_kind, to, 0, kCopyToEndAndInitializeToHole);
   }
 
+  virtual void GrowCapacityAndConvert(Handle<JSObject> object,
+                                      uint32_t capacity) = 0;
+
   virtual Handle<FixedArray> AddElementsToFixedArray(
       Handle<JSObject> receiver, Handle<FixedArray> to,
       FixedArray::KeyFilter filter) = 0;

src/lookup.cc

@@ -121,26 +121,10 @@ void LookupIterator::PrepareForDataProperty(Handle<Object> value) {
       JSObject::UpdateAllocationSite(holder, new_kind);
       if (IsFastDoubleElementsKind(old_kind) !=
           IsFastDoubleElementsKind(new_kind)) {
-        Handle<FixedArrayBase> old_elements(holder->elements());
-        int capacity = old_elements->length();
-        Handle<FixedArrayBase> new_elements;
-        if (IsFastDoubleElementsKind(new_kind)) {
-          new_elements = factory()->NewFixedDoubleArray(capacity);
-        } else {
-          new_elements = factory()->NewFixedArray(capacity);
-        }
-
+        uint32_t capacity = holder->elements()->length();
         ElementsAccessor* accessor = ElementsAccessor::ForKind(new_kind);
-        accessor->CopyElements(holder, new_elements, old_kind);
-
-        JSObject::ValidateElements(holder);
-        JSObject::SetMapAndElements(holder, holder_map_, new_elements);
-
-        if (FLAG_trace_elements_transitions) {
-          JSObject::PrintElementsTransition(
-              stdout, holder, old_kind, old_elements, new_kind, new_elements);
-        }
-        // SetMapAndElements above migrated the object. No reloading of property
+        accessor->GrowCapacityAndConvert(holder, capacity);
+        // GrowCapacityAndConvert migrated the object. No reloading of property
         // infomation is necessary for elements.
         return;
       } else if (FLAG_trace_elements_transitions) {

src/objects.cc

@@ -11874,49 +11874,14 @@ Handle<FixedArray> JSObject::SetFastElementsCapacityAndLength(
 }
 
 
-Handle<FixedArrayBase> JSObject::SetFastDoubleElementsCapacity(
-    Handle<JSObject> object, int capacity) {
-  // We should never end in here with a pixel or external array.
-  DCHECK(!object->HasExternalArrayElements());
-
-  Handle<FixedArrayBase> elems =
-      object->GetIsolate()->factory()->NewFixedDoubleArray(capacity);
-
-  ElementsKind elements_kind = object->GetElementsKind();
-  CHECK(elements_kind != SLOPPY_ARGUMENTS_ELEMENTS);
-  ElementsKind new_elements_kind = elements_kind;
-  if (IsHoleyElementsKind(elements_kind)) {
-    new_elements_kind = FAST_HOLEY_DOUBLE_ELEMENTS;
-  } else {
-    new_elements_kind = FAST_DOUBLE_ELEMENTS;
-  }
-
-  Handle<Map> new_map = GetElementsTransitionMap(object, new_elements_kind);
-
-  Handle<FixedArrayBase> old_elements(object->elements());
+void JSObject::SetFastDoubleElementsCapacityAndLength(Handle<JSObject> object,
+                                                      int capacity,
+                                                      int length) {
   ElementsAccessor* accessor = ElementsAccessor::ForKind(FAST_DOUBLE_ELEMENTS);
-  accessor->CopyElements(object, elems, elements_kind);
-
-  JSObject::ValidateElements(object);
-  JSObject::SetMapAndElements(object, new_map, elems);
-
-  if (FLAG_trace_elements_transitions) {
-    PrintElementsTransition(stdout, object, elements_kind, old_elements,
-                            object->GetElementsKind(), elems);
-  }
-
-  return elems;
-}
-
-
-Handle<FixedArrayBase> JSObject::SetFastDoubleElementsCapacityAndLength(
-    Handle<JSObject> object, int capacity, int length) {
-  Handle<FixedArrayBase> new_elements =
-      SetFastDoubleElementsCapacity(object, capacity);
+  accessor->GrowCapacityAndConvert(object, capacity);
   if (object->IsJSArray()) {
     Handle<JSArray>::cast(object)->set_length(Smi::FromInt(length));
   }
-  return new_elements;
 }
 
 

src/objects.h

@@ -2049,8 +2049,6 @@ class JSObject: public JSReceiver {
   static Handle<FixedArray> SetFastElementsCapacity(
       Handle<JSObject> object, int capacity,
       SetFastElementsCapacitySmiMode smi_mode);
-  static Handle<FixedArrayBase> SetFastDoubleElementsCapacity(
-      Handle<JSObject> object, int capacity);
 
   // Replace the elements' backing store with fast elements of the given
   // capacity.  Update the length for JSArrays.  Returns the new backing
@@ -2060,8 +2058,8 @@ class JSObject: public JSReceiver {
       int capacity,
       int length,
       SetFastElementsCapacitySmiMode smi_mode);
-  static Handle<FixedArrayBase> SetFastDoubleElementsCapacityAndLength(
-      Handle<JSObject> object, int capacity, int length);
+  static void SetFastDoubleElementsCapacityAndLength(Handle<JSObject> object,
+                                                     int capacity, int length);
 
   // Lookup interceptors are used for handling properties controlled by host
   // objects.

src/runtime/runtime-array.cc

@@ -1258,16 +1258,7 @@ RUNTIME_FUNCTION(Runtime_GrowArrayElements) {
     }
 
     uint32_t new_capacity = JSObject::NewElementsCapacity(index + 1);
-    ElementsKind kind = object->GetElementsKind();
-    if (IsFastDoubleElementsKind(kind)) {
-      JSObject::SetFastDoubleElementsCapacity(object, new_capacity);
-    } else {
-      JSObject::SetFastElementsCapacitySmiMode set_capacity_mode =
-          object->HasFastSmiElements() ? JSObject::kAllowSmiElements
-                                       : JSObject::kDontAllowSmiElements;
-      JSObject::SetFastElementsCapacity(object, new_capacity,
-                                        set_capacity_mode);
-    }
+    object->GetElementsAccessor()->GrowCapacityAndConvert(object, new_capacity);
   }
 
   // On success, return the fixed array elements.