[runtime] Record runtime call stats for Map::TransitionTo*Property, JSObject::OptimizeAsPrototype t…

src/lookup.cc

 // Copyright 2014 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/lookup.h"
 
 #include "src/bootstrapper.h"
 #include "src/deoptimizer.h"
 #include "src/elements.h"
 #include "src/field-type.h"
@@ skipping 334 matching lines @@
 }
 
 
 void LookupIterator::Delete() {
   Handle<JSReceiver> holder = Handle<JSReceiver>::cast(holder_);
   if (IsElement()) {
     Handle<JSObject> object = Handle<JSObject>::cast(holder);
     ElementsAccessor* accessor = object->GetElementsAccessor();
     accessor->Delete(object, number_);
   } else {
-    PropertyNormalizationMode mode = holder->map()->is_prototype_map()
-                                         ? KEEP_INOBJECT_PROPERTIES
-                                         : CLEAR_INOBJECT_PROPERTIES;
+    bool is_prototype_map = holder->map()->is_prototype_map();
+    RuntimeCallTimerScope stats_scope(
+        isolate_, is_prototype_map
+                      ? &RuntimeCallStats::PrototypeObject_DeleteProperty
+                      : &RuntimeCallStats::Object_DeleteProperty);

[Camillo Bruni, 2016/05/11 13:01:46]

I hope this case doesn't happen too much, I've seen quite some impact by the
counter when using them for the builtins. That's why I added the separate branch
that only jumps there if we enable the flag. Otherwise I could still see the
overhead, since clang inlined the timer scope nevertheless and probably reserved
stack in either case.

+
+    PropertyNormalizationMode mode =
+        is_prototype_map ? KEEP_INOBJECT_PROPERTIES : CLEAR_INOBJECT_PROPERTIES;
 
     if (holder->HasFastProperties()) {
       JSObject::NormalizeProperties(Handle<JSObject>::cast(holder), mode, 0,
                                     "DeletingProperty");
       ReloadPropertyInformation<false>();
     }
     // TODO(verwaest): Get rid of the name_ argument.
     JSReceiver::DeleteNormalizedProperty(holder, name_, number_);
     if (holder->IsJSObject()) {
       JSObject::ReoptimizeIfPrototype(Handle<JSObject>::cast(holder));
@@ skipping 395 matching lines @@
     case v8::internal::kAccessor:
       return ACCESSOR;
   }
 
   UNREACHABLE();
   return state_;
 }
 
 }  // namespace internal
 }  // namespace v8