Bookkeeping for allocation site pretenuring

src/allocation-site-scopes.cc

Index: src/allocation-site-scopes.cc
diff --git a/src/allocation-site-scopes.cc b/src/allocation-site-scopes.cc
index 31120b902531a4c5bd54c9f010e0d74ea67a0329..bbfb39b122c336ad7e8df8846550fb5fec85d831 100644
--- a/src/allocation-site-scopes.cc
+++ b/src/allocation-site-scopes.cc
@@ -82,4 +82,21 @@ void AllocationSiteCreationContext::ExitScope(
   }
 }
 
+
+bool AllocationSiteUsageContext::ShouldCreateMemento(Handle<JSObject> object) {
+  if (activated_ && AllocationSite::CanTrack(object->map()->instance_type())) {
+    if (FLAG_allocation_site_pretenuring ||
+        AllocationSite::GetMode(object->GetElementsKind()) ==
+        TRACK_ALLOCATION_SITE) {
+      if (FLAG_trace_creation_allocation_sites) {
+        PrintF("*** Creating Memento for %s %p\n",
+               object->IsJSArray() ? "JSArray" : "JSObject",
+               static_cast<void*>(*object));
+      }
+      return true;
+    }
+  }
+  return false;
+}
+
 } }  // namespace v8::internal