--- a/hotspot/src/share/vm/ci/ciMethod.hpp	Tue Jan 10 18:48:08 2017 +0000
+++ b/hotspot/src/share/vm/ci/ciMethod.hpp	Wed Jan 11 09:40:42 2017 +0100
@@ -136,15 +136,19 @@
     check_is_loaded();
     return _signature->size() + (_flags.is_static() ? 0 : 1);
   }
-  // Report the number of elements on stack when invoking this method.
-  // This is different than the regular arg_size because invokedynamic
-  // has an implicit receiver.
+  // Report the number of elements on stack when invoking the current method.
+  // If the method is loaded, arg_size() gives precise information about the
+  // number of stack elements (using the method's signature and its flags).
+  // However, if the method is not loaded, the number of stack elements must
+  // be determined differently, as the method's flags are not yet available.
+  // The invoke_arg_size() method assumes in that case that all bytecodes except
+  // invokestatic and invokedynamic have a receiver that is also pushed onto the
+  // stack by the caller of the current method.
   int invoke_arg_size(Bytecodes::Code code) const {
     if (is_loaded()) {
       return arg_size();
     } else {
       int arg_size = _signature->size();
-      // Add a receiver argument, maybe:
       if (code != Bytecodes::_invokestatic &&
           code != Bytecodes::_invokedynamic) {
         arg_size++;