[runtime] Avoid @@isConcatSpreadable lookup for fast path Array.prototype.concat

src/heap/heap.cc

 // Copyright 2012 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/heap/heap.h"
 
 #include "src/accessors.h"
 #include "src/api.h"
 #include "src/ast/scopeinfo.h"
 #include "src/base/bits.h"
@@ skipping 1202 matching lines @@
 
   Object* context = native_contexts_list();
   while (!context->IsUndefined()) {
     // GC can happen when the context is not fully initialized,
     // so the cache can be undefined.
     Object* cache =
         Context::cast(context)->get(Context::NORMALIZED_MAP_CACHE_INDEX);
     if (!cache->IsUndefined()) {
       NormalizedMapCache::cast(cache)->Clear();
     }
-    context = Context::cast(context)->get(Context::NEXT_CONTEXT_LINK);
+    context = Context::cast(context)->next_context_link();
   }
 }
 
 
 void Heap::UpdateSurvivalStatistics(int start_new_space_size) {
   if (start_new_space_size == 0) return;
 
   promotion_ratio_ = (static_cast<double>(promoted_objects_size_) /
                       static_cast<double>(start_new_space_size) * 100);
 
@@ skipping 1595 matching lines @@
   set_empty_script(*script);
 
   Handle<PropertyCell> cell = factory->NewPropertyCell();
   cell->set_value(Smi::FromInt(Isolate::kArrayProtectorValid));
   set_array_protector(*cell);
 
   cell = factory->NewPropertyCell();
   cell->set_value(the_hole_value());
   set_empty_property_cell(*cell);
 
-  Handle<PropertyCell> species_cell = factory->NewPropertyCell();
-  species_cell->set_value(Smi::FromInt(Isolate::kArrayProtectorValid));
+  Handle<Cell> is_concat_spreadable_cell = factory->NewCell(
+      handle(Smi::FromInt(Isolate::kArrayProtectorValid), isolate()));
+  set_is_concat_spreadable_protector(*is_concat_spreadable_cell);
+
+  Handle<Cell> species_cell = factory->NewCell(
+      handle(Smi::FromInt(Isolate::kArrayProtectorValid), isolate()));
   set_species_protector(*species_cell);
 
   set_weak_stack_trace_list(Smi::FromInt(0));
 
   set_noscript_shared_function_infos(Smi::FromInt(0));
 
   // Initialize keyed lookup cache.
   isolate_->keyed_lookup_cache()->Clear();
 
   // Initialize context slot cache.
@@ skipping 3496 matching lines @@
 }
 
 
 // static
 int Heap::GetStaticVisitorIdForMap(Map* map) {
   return StaticVisitorBase::GetVisitorId(map);
 }
 
 }  // namespace internal
 }  // namespace v8