ARM: Implement runtime function for array literal transitions.

src/builtins.cc

 // Copyright 2011 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 757 matching lines @@
   CopyElements(heap, &no_gc, result_elms, 0, elms, k, result_len);
 
   // Set elements.
   result_array->set_elements(result_elms);
 
   // Set the length.
   result_array->set_length(Smi::FromInt(result_len));
 
   // Set the ElementsKind.
   ElementsKind elements_kind = JSObject::cast(receiver)->GetElementsKind();
-  if (result_array->GetElementsKind() != elements_kind) {
+  if (IsMoreGeneralElementsKindTransition(result_array->GetElementsKind(),
+                                          elements_kind)) {
     MaybeObject* maybe = result_array->TransitionElementsKind(elements_kind);
     if (maybe->IsFailure()) return maybe;
   }
   return result_array;
 }
 
 
 BUILTIN(ArraySplice) {
   Heap* heap = isolate->heap();
   Object* receiver = *args.receiver();
@@ skipping 79 matching lines @@
                  actual_delete_count);
 
     // Set elements.
     result_array->set_elements(result_elms);
 
     // Set the length.
     result_array->set_length(Smi::FromInt(actual_delete_count));
 
     // Set the ElementsKind.
     ElementsKind elements_kind = array->GetElementsKind();
-    if (result_array->GetElementsKind() != elements_kind) {
+    if (IsMoreGeneralElementsKindTransition(result_array->GetElementsKind(),
+                                            elements_kind)) {
       MaybeObject* maybe = result_array->TransitionElementsKind(elements_kind);
       if (maybe->IsFailure()) return maybe;
     }
   }
 
   int item_count = (n_arguments > 1) ? (n_arguments - 2) : 0;
   int new_length = len - actual_delete_count + item_count;
 
   bool elms_changed = false;
   if (item_count < actual_delete_count) {
@@ skipping 897 matching lines @@
   return Handle<Code>(code_address);                        \
 }
 BUILTIN_LIST_C(DEFINE_BUILTIN_ACCESSOR_C)
 BUILTIN_LIST_A(DEFINE_BUILTIN_ACCESSOR_A)
 BUILTIN_LIST_DEBUG_A(DEFINE_BUILTIN_ACCESSOR_A)
 #undef DEFINE_BUILTIN_ACCESSOR_C
 #undef DEFINE_BUILTIN_ACCESSOR_A
 
 
 } }  // namespace v8::internal