Re: [PATCH 3/4 v15] Add support for lookup, overload resolution and invocation of C++ xmethod (was debug methods)

[Doug Evans <dje at google dot com>]

Siva Chandra writes:
 > As explained in the posting of 2/4, the changes in this part from v14
 > are the name and that find_overload_match returns the matching xmethod
 > as a TYPE_CODE_XMETHOD value.
 > 
 > The 2/4 posting: https://sourceware.org/ml/gdb-patches/2014-04/msg00585.html
 > 
 > ChangeLog
 > 2014-04-28  Siva Chandra Reddy  <sivachandra@google.com>
 > 
 >         * eval.c (evaluate_subexp_standard): Call the xmethod if the
 >         best match method returned by find_overload_match is an xmethod.
 >         * valarith.c (value_x_binop, value_x_unop): Call the xmethod if
 >         the best matching operator returned by find_overload_match is an
 >         xmethod.
 >         * valops.c: #include "extension.h".
 >         (find_method_list): Add "fn_list" and "dm_worker_vec" arguments.
 >         Return void.  The list of matching source methods is returned in
 >         "fn_list" and a vector of matching debug method workers is
 >         returned in "dm_worker_vec".  Update all callers.
 >         (value_find_oload_method_list): Likewise.
 >         (find_oload_champ): Add "dm_worker_vec" parameter.  If it is
 >         non-NULL, then the index of the best matching method in this
 >         vector is returned.  Update all callers.
 >         (find_overload_match): Include xmethods while performing overload
 >         resolution.
 >         (value_has_indirect_dynamic_type, cast_args_to_param_types,
 >         equal_param_types_p, derived_hides_base_method): New functions.
 > diff --git a/gdb/eval.c b/gdb/eval.c
 > index 3e62ead..c9f402b 100644
 > --- a/gdb/eval.c
 > +++ b/gdb/eval.c
 > @@ -1758,11 +1758,25 @@ evaluate_subexp_standard (struct type *expect_type,
 >  	    error (_("Expression of type other than "
 >  		     "\"Function returning ...\" used as function"));
 >  	}
 > -      if (TYPE_CODE (value_type (argvec[0])) == TYPE_CODE_INTERNAL_FUNCTION)
 > -	return call_internal_function (exp->gdbarch, exp->language_defn,
 > -				       argvec[0], nargs, argvec + 1);
 > +      switch (TYPE_CODE (value_type (argvec[0])))
 > +	{
 > +	case TYPE_CODE_INTERNAL_FUNCTION:
 > +	  return call_internal_function (exp->gdbarch, exp->language_defn,
 > +					 argvec[0], nargs, argvec + 1);
 > +	case TYPE_CODE_XMETHOD:
 > +	  {
 > +	    struct value *retval;
 > +	    struct cleanup *xm_cleanup;
 > +
 > +	    xm_cleanup = make_cleanup (free_xmethod_value, argvec[0]);
 > +	    retval = call_xmethod (argvec[0], nargs, argvec + 1);
 > +	    do_cleanups (xm_cleanup);
 >  
 > -      return call_function_by_hand (argvec[0], nargs, argvec + 1);
 > +	    return retval;
 > +	  }
 > +	default:
 > +	  return call_function_by_hand (argvec[0], nargs, argvec + 1);
 > +	}
 >        /* pai: FIXME save value from call_function_by_hand, then adjust
 >  	 pc by adjust_fn_pc if +ve.  */
 >  

Hi.
I wonder if we could simplify some code by having a wrapper function
to call_internal_function, call_xmethod, call_function_by_hand.
The above code would be put into this function, and
evaluate_subexp_standard would just call this function.
I'm hoping it could be used everywhere you add calls to call_xmethod.