Becuase of cross-context calls, hydrogen-based Array constructor needs to ensure

src/hydrogen.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 1845 matching lines @@
   AddInstruction(new(zone()) HStoreNamedField(alloc_site,
       isolate()->factory()->payload_string(),
       payload,
       true,
       Representation::Tagged(),
       AllocationSiteInfo::kPayloadOffset));
   return alloc_site;
 }
 
 
+HInstruction* HGraphBuilder::BuildGetNativeContext(HValue* context) {
+  HInstruction* global_object = AddInstruction(new(zone())
+                                               HGlobalObject(context));
+  HInstruction* native_context = AddInstruction(new(zone())
+      HLoadNamedField(global_object, true, Representation::Tagged(),
+                      GlobalObject::kNativeContextOffset));
+  return native_context;
+}
+
+
+HInstruction* HGraphBuilder::BuildGetArrayFunction(HValue* context) {
+  HInstruction* native_context = BuildGetNativeContext(context);
+  int offset = Context::kHeaderSize +
+      kPointerSize * Context::ARRAY_FUNCTION_INDEX;
+  HInstruction* array_function = AddInstruction(new(zone())
+      HLoadNamedField(native_context, true, Representation::Tagged(), offset));
+  return array_function;
+}
+
+
 HGraphBuilder::JSArrayBuilder::JSArrayBuilder(HGraphBuilder* builder,
                                               ElementsKind kind,
                                               HValue* allocation_site_payload,
                                               AllocationSiteMode mode) :
         builder_(builder),
         kind_(kind),
         allocation_site_payload_(allocation_site_payload) {
   if (mode == DONT_TRACK_ALLOCATION_SITE) {
     mode_ = mode;
   } else {
     mode_ = AllocationSiteInfo::GetMode(kind);
   }
 }
 
 
 HValue* HGraphBuilder::JSArrayBuilder::EmitMapCode(HValue* context) {
-  // Get the global context, the native context, the map array
-  HInstruction* global_object = AddInstruction(new(zone())
-      HGlobalObject(context));
-  HInstruction* native_context = AddInstruction(new(zone())
-      HLoadNamedField(global_object, true, Representation::Tagged(),
-                      GlobalObject::kNativeContextOffset));
+  HInstruction* native_context = builder()->BuildGetNativeContext(context);
   int offset = Context::kHeaderSize +
       kPointerSize * Context::JS_ARRAY_MAPS_INDEX;
   HInstruction* map_array = AddInstruction(new(zone())
       HLoadNamedField(native_context, true, Representation::Tagged(), offset));
   offset = kind_ * kPointerSize + FixedArrayBase::kHeaderSize;
   return AddInstruction(new(zone()) HLoadNamedField(
       map_array, true, Representation::Tagged(), offset));
 }
 
 
@@ skipping 10375 matching lines @@
     }
   }
 
 #ifdef DEBUG
   if (graph_ != NULL) graph_->Verify(false);  // No full verify.
   if (allocator_ != NULL) allocator_->Verify();
 #endif
 }
 
 } }  // namespace v8::internal