First take on custom call generators.

src/objects-inl.h

 // Copyright 2006-2008 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 2343 matching lines @@
 ACCESSORS(BreakPointInfo, code_position, Smi, kCodePositionIndex)
 ACCESSORS(BreakPointInfo, source_position, Smi, kSourcePositionIndex)
 ACCESSORS(BreakPointInfo, statement_position, Smi, kStatementPositionIndex)
 ACCESSORS(BreakPointInfo, break_point_objects, Object, kBreakPointObjectsIndex)
 #endif
 
 ACCESSORS(SharedFunctionInfo, construct_stub, Code, kConstructStubOffset)
 ACCESSORS(SharedFunctionInfo, name, Object, kNameOffset)
 ACCESSORS(SharedFunctionInfo, instance_class_name, Object,
           kInstanceClassNameOffset)
-ACCESSORS(SharedFunctionInfo, function_data, Object,
-          kExternalReferenceDataOffset)
+ACCESSORS(SharedFunctionInfo, function_data, Object, kFunctionDataOffset)
 ACCESSORS(SharedFunctionInfo, script, Object, kScriptOffset)
 ACCESSORS(SharedFunctionInfo, debug_info, Object, kDebugInfoOffset)
 ACCESSORS(SharedFunctionInfo, inferred_name, String, kInferredNameOffset)
 ACCESSORS(SharedFunctionInfo, this_property_assignments, Object,
           kThisPropertyAssignmentsOffset)
 
 BOOL_ACCESSORS(FunctionTemplateInfo, flag, hidden_prototype,
                kHiddenPrototypeBit)
 BOOL_ACCESSORS(FunctionTemplateInfo, flag, undetectable, kUndetectableBit)
 BOOL_ACCESSORS(FunctionTemplateInfo, flag, needs_access_check,
@@ skipping 70 matching lines @@
   CONDITIONAL_WRITE_BARRIER(this, kCodeOffset, mode);
 }
 
 
 bool SharedFunctionInfo::is_compiled() {
   // TODO(1242782): Create a code kind for uncompiled code.
   return code()->kind() != Code::STUB;
 }
 
 
+bool SharedFunctionInfo::IsApiFunction() {
+  return function_data()->IsFunctionTemplateInfo();
+}
+
+
+FunctionTemplateInfo* SharedFunctionInfo::get_api_func_data() {
+  ASSERT(IsApiFunction());
+  return FunctionTemplateInfo::cast(function_data());
+}
+
+
+bool SharedFunctionInfo::HasCustomCallGenerator() {
+  return function_data()->IsProxy();
+}
+
+
 bool JSFunction::IsBoilerplate() {
   return map() == Heap::boilerplate_function_map();
 }
 
 
 bool JSFunction::IsBuiltin() {
   return context()->global()->IsJSBuiltinsObject();
 }
 
 
@@ skipping 596 matching lines @@
 #undef WRITE_INT_FIELD
 #undef READ_SHORT_FIELD
 #undef WRITE_SHORT_FIELD
 #undef READ_BYTE_FIELD
 #undef WRITE_BYTE_FIELD
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_OBJECTS_INL_H_