In case of holder with fast properties that allows to fetch the property

immediately if holder has this property or saves binary search on holder if
property doesn't belong to holder.  Of course, in the cases when named getter
returns nothing.

That gives ~20% for dom benchmark/Document Object String Get, speeds up overall
dom_perf (not dramatically) and overall score for peacekeeper.  Strange, but DOM
part of peacekeepr runs somewhat slower.
Review URL: http://codereview.chromium.org/118118

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@2093 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/objects-inl.h

@@ -2554,6 +2554,24 @@ bool JSObject::HasElement(uint32_t index) {
 }
 
 
+Smi* JSObject::InterceptorPropertyLookupHint(String* name) {
+  // TODO(antonm): Do we want to do any shortcuts for global object?
+  if (HasFastProperties()) {
+    LookupResult lookup;
+    LocalLookupRealNamedProperty(name, &lookup);
+    if (lookup.IsValid()) {
+      if (lookup.type() == FIELD && lookup.IsCacheable()) {
+        return Smi::FromInt(lookup.GetFieldIndex());
+      }
+    } else {
+      return Smi::FromInt(kLookupInPrototype);
+    }
+  }
+
+  return Smi::FromInt(kLookupInHolder);
+}
+
+
 bool AccessorInfo::all_can_read() {
   return BooleanBit::get(flag(), kAllCanReadBit);
 }

src/objects.cc

@@ -5617,9 +5617,10 @@ Object* JSObject::GetPropertyPostInterceptor(JSObject* receiver,
 }
 
 
-Object* JSObject::GetPropertyWithInterceptor(JSObject* receiver,
-                                             String* name,
-                                             PropertyAttributes* attributes) {
+Object* JSObject::GetPropertyWithInterceptorProper(
+    JSObject* receiver,
+    String* name,
+    PropertyAttributes* attributes) {
   HandleScope scope;
   Handle<InterceptorInfo> interceptor(GetNamedInterceptor());
   Handle<JSObject> receiver_handle(receiver);
@@ -5647,12 +5648,75 @@ Object* JSObject::GetPropertyWithInterceptor(JSObject* receiver,
     }
   }
 
-  Object* raw_result = holder_handle->GetPropertyPostInterceptor(
+  return NULL;
+}
+
+
+Object* JSObject::GetInterceptorPropertyWithLookupHint(
+    JSObject* receiver,
+    Smi* lookup_hint,
+    String* name,
+    PropertyAttributes* attributes) {
+  HandleScope scope;
+  Handle<JSObject> receiver_handle(receiver);
+  Handle<JSObject> holder_handle(this);
+  Handle<String> name_handle(name);
+
+  Object* result = GetPropertyWithInterceptorProper(receiver, name, attributes);
+  if (result) return result;
+
+  int property_index = lookup_hint->value();
+  if (property_index >= 0) {
+    result = holder_handle->FastPropertyAt(property_index);
+  } else {
+    switch (property_index) {
+      case kLookupInPrototype: {
+          Object* pt = holder_handle->GetPrototype();
+          *attributes = ABSENT;
+          if (pt == Heap::null_value()) return Heap::undefined_value();
+          result = pt->GetPropertyWithReceiver(
+              *receiver_handle,
+              *name_handle,
+              attributes);
+          RETURN_IF_SCHEDULED_EXCEPTION();
+        }
+        break;
+
+      case kLookupInHolder:
+        result = holder_handle->GetPropertyPostInterceptor(
+            *receiver_handle,
+            *name_handle,
+            attributes);
+        RETURN_IF_SCHEDULED_EXCEPTION();
+        break;
+
+      default:
+        UNREACHABLE();
+    }
+  }
+
+  return result;
+}
+
+
+Object* JSObject::GetPropertyWithInterceptor(
+    JSObject* receiver,
+    String* name,
+    PropertyAttributes* attributes) {
+  HandleScope scope;
+  Handle<JSObject> receiver_handle(receiver);
+  Handle<JSObject> holder_handle(this);
+  Handle<String> name_handle(name);
+
+  Object* result = GetPropertyWithInterceptorProper(receiver, name, attributes);
+  if (result) return result;
+
+  result = holder_handle->GetPropertyPostInterceptor(
       *receiver_handle,
       *name_handle,
       attributes);
   RETURN_IF_SCHEDULED_EXCEPTION();
-  return raw_result;
+  return result;
 }
 
 

src/stub-cache.cc

@@ -719,10 +719,12 @@ Object* LoadInterceptorProperty(Arguments args) {
   JSObject* recv = JSObject::cast(args[0]);
   JSObject* holder = JSObject::cast(args[1]);
   String* name = String::cast(args[2]);
+  Smi* lookup_hint = Smi::cast(args[3]);
   ASSERT(holder->HasNamedInterceptor());
   PropertyAttributes attr = NONE;
-  Object* result = holder->GetPropertyWithInterceptor(recv, name, &attr);
 
+  Object* result = holder->GetInterceptorPropertyWithLookupHint(
+      recv, lookup_hint, name, &attr);
   if (result->IsFailure()) return result;
 
   // If the property is present, return it.