[elements, turbofan] Implement simple GrowElements

src/runtime/runtime-array.cc

 // Copyright 2014 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/runtime/runtime-utils.h"
 
 #include "src/arguments.h"
 #include "src/code-stubs.h"
 #include "src/conversions-inl.h"
 #include "src/elements.h"
@@ skipping 357 matching lines @@
   CONVERT_NUMBER_CHECKED(int, key, Int32, args[1]);
 
   if (key < 0) {
     return object->elements();
   }
 
   uint32_t capacity = static_cast<uint32_t>(object->elements()->length());
   uint32_t index = static_cast<uint32_t>(key);
 
   if (index >= capacity) {
-    if (object->map()->is_prototype_map() ||
-        object->WouldConvertToSlowElements(index)) {
-      // We don't want to allow operations that cause lazy deopt. Return a Smi
-      // as a signal that optimized code should eagerly deoptimize.
+    if (!object->GetElementsAccessor()->GrowCapacity(object, index)) {
       return Smi::FromInt(0);
     }
-
-    uint32_t new_capacity = JSObject::NewElementsCapacity(index + 1);
-    object->GetElementsAccessor()->GrowCapacityAndConvert(object, new_capacity);
   }
 
   // On success, return the fixed array elements.
   return object->elements();
 }
 
 
 RUNTIME_FUNCTION(Runtime_HasComplexElements) {
   HandleScope scope(isolate);
   DCHECK(args.length() == 1);
@@ skipping 243 matching lines @@
       if (search_element->StrictEquals(*element_k)) {
         return *index_obj;
       }
     }
   }
   return Smi::FromInt(-1);
 }
 
 }  // namespace internal
 }  // namespace v8