[PTX] simplify calling struct

[Bernhard Reutner-Fischer]

On December 16, 2015 2:53:51 PM GMT+01:00, Nathan Sidwell <nathan@acm.org> wrote:
>PTX's machine_function structure squirrels away the function type to
>calculate 
>the presence of  varadic args later,  rather than calculate it
>immediately.  It 
>also uses an rtx field as a boolean.  This patch reorganizes it with
>less 
>verbose names and more apt types.


+  bool is_varadic;  /* This call is varadic  */
+  bool has_varadic;  /* Current function has a varadic call.  */

Just curious what varadic is? Is that maybe somehow related to variadic?

TIA,
>
>I also noticed that nvptx_hard_regno_mode_ok wasn't  being used, so
>that's deleted.
>
>nathan