Properly handle FastDoubleArrays in Runtime_MoveArrayContents

src/runtime.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 9571 matching lines @@
 // Move contents of argument 0 (an array) to argument 1 (an array)
 RUNTIME_FUNCTION(MaybeObject*, Runtime_MoveArrayContents) {
   ASSERT(args.length() == 2);
   CONVERT_CHECKED(JSArray, from, args[0]);
   CONVERT_CHECKED(JSArray, to, args[1]);
   HeapObject* new_elements = from->elements();
   MaybeObject* maybe_new_map;
   if (new_elements->map() == isolate->heap()->fixed_array_map() ||
       new_elements->map() == isolate->heap()->fixed_cow_array_map()) {
     maybe_new_map = to->map()->GetFastElementsMap();
+  } else if (new_elements->map() ==
+             isolate->heap()->fixed_double_array_map()) {
+    maybe_new_map = to->map()->GetFastDoubleElementsMap();
   } else {
     maybe_new_map = to->map()->GetSlowElementsMap();
   }
   Object* new_map;
   if (!maybe_new_map->ToObject(&new_map)) return maybe_new_map;
   to->set_map(Map::cast(new_map));
   to->set_elements(new_elements);
   to->set_length(from->length());
   Object* obj;
   { MaybeObject* maybe_obj = from->ResetElements();
@@ skipping 67 matching lines @@
     for (int i = 0; i < keys_length; i++) {
       Object* key = keys->get(i);
       uint32_t index = 0;
       if (!key->ToArrayIndex(&index) || index >= length) {
         // Zap invalid keys.
         keys->set_undefined(i);
       }
     }
     return *isolate->factory()->NewJSArrayWithElements(keys);
   } else {
-    ASSERT(array->HasFastElements());
+    ASSERT(array->HasFastElements() || array->HasFastDoubleElements());
     Handle<FixedArray> single_interval = isolate->factory()->NewFixedArray(2);
     // -1 means start of array.
     single_interval->set(0, Smi::FromInt(-1));
+    FixedArrayBase* elements = FixedArrayBase::cast(array->elements());
     uint32_t actual_length =
-        static_cast<uint32_t>(FixedArray::cast(array->elements())->length());
+        static_cast<uint32_t>(elements->length());
     uint32_t min_length = actual_length < length ? actual_length : length;
     Handle<Object> length_object =
         isolate->factory()->NewNumber(static_cast<double>(min_length));
     single_interval->set(1, *length_object);
     return *isolate->factory()->NewJSArrayWithElements(single_interval);
   }
 }
 
 
 // DefineAccessor takes an optional final argument which is the
@@ skipping 3067 matching lines @@
   } else {
     // Handle last resort GC and make sure to allow future allocations
     // to grow the heap without causing GCs (if possible).
     isolate->counters()->gc_last_resort_from_js()->Increment();
     isolate->heap()->CollectAllGarbage(false);
   }
 }
 
 
 } }  // namespace v8::internal