Elide hole checks on KeyedLoads of holey double arrays.

src/heap.cc

 // Copyright 2012 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 5159 matching lines @@
   return result;
 }
 
 
 MaybeObject* Heap::AllocateJSArray(
     ElementsKind elements_kind,
     PretenureFlag pretenure) {
   Context* native_context = isolate()->context()->native_context();
   JSFunction* array_function = native_context->array_function();
   Map* map = array_function->initial_map();
-  Object* maybe_map_array = native_context->js_array_maps();
-  if (!maybe_map_array->IsUndefined()) {
-    Object* maybe_transitioned_map =
-        FixedArray::cast(maybe_map_array)->get(elements_kind);
-    if (!maybe_transitioned_map->IsUndefined()) {
-      map = Map::cast(maybe_transitioned_map);
-    }
-  }
-
+  Map* transition_map = isolate()->get_initial_js_array_map(elements_kind);
+  if (transition_map != NULL) map = transition_map;
   return AllocateJSObjectFromMap(map, pretenure);
 }
 
 
 MaybeObject* Heap::AllocateJSArrayWithAllocationSite(
     ElementsKind elements_kind,
     Handle<Object> allocation_site_info_payload) {
   Context* native_context = isolate()->context()->native_context();
   JSFunction* array_function = native_context->array_function();
   Map* map = array_function->initial_map();
@@ skipping 2684 matching lines @@
   if (FLAG_parallel_recompilation) {
     heap_->relocation_mutex_->Lock();
 #ifdef DEBUG
     heap_->relocation_mutex_locked_by_optimizer_thread_ =
         heap_->isolate()->optimizing_compiler_thread()->IsOptimizerThread();
 #endif  // DEBUG
   }
 }
 
 } }  // namespace v8::internal