Adds the possibility of setting a Code object as the callback of a FunctionTemplate.

src/execution.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/execution.h"
 
 #include "src/bootstrapper.h"
 #include "src/codegen.h"
 #include "src/deoptimizer.h"
 #include "src/isolate-inl.h"
@@ skipping 118 matching lines @@
                                     Handle<Object> receiver, int argc,
                                     Handle<Object> argv[]) {
   // Convert calls on global objects to be calls on the global
   // receiver instead to avoid having a 'this' pointer which refers
   // directly to a global object.
   if (receiver->IsJSGlobalObject()) {
     receiver =
         handle(Handle<JSGlobalObject>::cast(receiver)->global_proxy(), isolate);
   }
 
+  bool is_callback = false;

[Benedikt Meurer, 2015/11/12 04:31:21]

Please add a TODO here, that this code will need cleanup once we know exactly
what we want in the end.

[epertoso, 2015/11/13 01:39:28]

I refactored the code a bit.

I'm not sure I understand your comment. With this patch, we will have two
possible callbacks: the regular FunctionCallback, and the 'fast' one which is
passed around as a code object. Do you foresee any way in which this might
change?

+  if (callable->IsJSFunction()) {
+    Handle<JSFunction> function = Handle<JSFunction>::cast(callable);
+    if (function->shared()->IsApiFunction()) {
+      Object* call_code = function->shared()->get_api_func_data()->call_code();
+      is_callback = call_code->IsCallHandlerInfo() &&
+                    !CallHandlerInfo::cast(call_code)->callback()->IsCode();
+    }
+  }
+
   // api callbacks can be called directly.
-  if (callable->IsJSFunction() &&
-      Handle<JSFunction>::cast(callable)->shared()->IsApiFunction()) {
+  if (is_callback) {
     Handle<JSFunction> function = Handle<JSFunction>::cast(callable);
     SaveContext save(isolate);
     isolate->set_context(function->context());
     // Do proper receiver conversion for non-strict mode api functions.
     if (!receiver->IsJSReceiver() &&
         is_sloppy(function->shared()->language_mode())) {
       if (receiver->IsUndefined() || receiver->IsNull()) {
         receiver = handle(function->global_proxy(), isolate);
       } else {
         ASSIGN_RETURN_ON_EXCEPTION(
@@ skipping 373 matching lines @@
 
   isolate_->counters()->stack_interrupts()->Increment();
   isolate_->counters()->runtime_profiler_ticks()->Increment();
   isolate_->runtime_profiler()->OptimizeNow();
 
   return isolate_->heap()->undefined_value();
 }
 
 }  // namespace internal
 }  // namespace v8