Bookkeeping for allocation site pretenuring

src/allocation-site-scopes.cc

 // Copyright 2013 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 65 matching lines @@
         PrintF("Setting AllocationSite (%p, %p) transition_info %p\n",
                static_cast<void*>(*top()),
                static_cast<void*>(*scope_site),
                static_cast<void*>(*object));
       }
     }
   }
 }
 
 
+bool AllocationSiteUsageContext::ShouldCreateMemento(Handle<JSObject> object) {
+  if (activated_) {
+    if (AllocationSite::CanTrack(object->map()->instance_type())) {
+      if (!FLAG_allocation_site_pretenuring) {
+        ASSERT(object->IsJSArray());
+        if (AllocationSite::GetMode(object->GetElementsKind()) ==
+            TRACK_ALLOCATION_SITE) {
+          if (FLAG_trace_creation_allocation_sites) {
+            PrintF("*** Creating Memento for JSArray %p\n",
+                   static_cast<void*>(*object));
+          }
+          return true;
+        }
+      } else {
+        ASSERT(FLAG_allocation_site_pretenuring);
+        if (FLAG_trace_creation_allocation_sites) {
+          PrintF("*** Creating Memento for JSObject/JSArray %p\n",
+                 static_cast<void*>(*object));
+        }
+        return true;
+      }
+    }
+  }
+  return false;
+}
+
+
 Handle<AllocationSite> AllocationSiteUsageContext::EnterNewScope() {
   if (top().is_null()) {
     InitializeTraversal(top_site_);
   } else {
     // Advance current site
     Object* nested_site = current()->nested_site();
     // Something is wrong if we advance to the end of the list here.
     ASSERT(nested_site->IsAllocationSite());
     update_current_site(AllocationSite::cast(nested_site));
   }
   return Handle<AllocationSite>(*current(), isolate());
 }
 
 
 void AllocationSiteUsageContext::ExitScope(
     Handle<AllocationSite> scope_site,
     Handle<JSObject> object) {
   // This assert ensures that we are pointing at the right sub-object in a
   // recursive walk of a nested literal.
   ASSERT(object.is_null() || *object == scope_site->transition_info());
 }
 
 } }  // namespace v8::internal