diff --git a/src/ic/call-optimization.cc b/src/ic/call-optimization.cc
index 45717b5..571b614 100644
--- a/src/ic/call-optimization.cc
+++ b/src/ic/call-optimization.cc
@@ -8,8 +8,16 @@
 namespace v8 {
 namespace internal {
 
-CallOptimization::CallOptimization(Handle<JSFunction> function) {
-  Initialize(function);
+CallOptimization::CallOptimization(Handle<Object> function) {
+  constant_function_ = Handle<JSFunction>::null();
+  is_simple_api_call_ = false;
+  expected_receiver_type_ = Handle<FunctionTemplateInfo>::null();
+  api_call_info_ = Handle<CallHandlerInfo>::null();
+  if (function->IsJSFunction()) {
+    Initialize(Handle<JSFunction>::cast(function));
+  } else if (function->IsFunctionTemplateInfo()) {
+    Initialize(Handle<FunctionTemplateInfo>::cast(function));
+  }
 }
 
 
@@ -27,9 +35,8 @@
     return Handle<JSObject>::null();
   }
   for (int depth = 1; true; depth++) {
-    if (!object_map->prototype()->IsJSObject()) break;
+    if (!object_map->has_hidden_prototype()) break;
     Handle<JSObject> prototype(JSObject::cast(object_map->prototype()));
-    if (!prototype->map()->is_hidden_prototype()) break;
     object_map = handle(prototype->map());
     if (expected_receiver_type_->IsTemplateFor(*object_map)) {
       *holder_lookup = kHolderFound;
@@ -80,13 +87,20 @@
   return false;
 }
 
+void CallOptimization::Initialize(
+    Handle<FunctionTemplateInfo> function_template_info) {
+  if (function_template_info->call_code()->IsUndefined()) return;
+  api_call_info_ =
+      handle(CallHandlerInfo::cast(function_template_info->call_code()));
+
+  if (!function_template_info->signature()->IsUndefined()) {
+    expected_receiver_type_ =
+        handle(FunctionTemplateInfo::cast(function_template_info->signature()));
+  }
+  is_simple_api_call_ = true;
+}
 
 void CallOptimization::Initialize(Handle<JSFunction> function) {
-  constant_function_ = Handle<JSFunction>::null();
-  is_simple_api_call_ = false;
-  expected_receiver_type_ = Handle<FunctionTemplateInfo>::null();
-  api_call_info_ = Handle<CallHandlerInfo>::null();
-
   if (function.is_null() || !function->is_compiled()) return;
 
   constant_function_ = function;