avr.c (avr_function_arg_advance): Fix thinko about when a value is actually passed in regs.

	* config/avr/avr.c (avr_function_arg_advance): Fix thinko about
	when a value is actually passed in regs.

From-SVN: r174898

gcc/ChangeLog

+2011-06-10  Georg-Johann Lay  <avr@gjlay.de>
+	
+	* config/avr/avr.c (avr_function_arg_advance): Fix thinko about
+	when a value is actually passed in regs.
+
 2011-06-10  Eric Botcazou  <ebotcazou@adacore.com>
 	    Laurent Roug  <laurent.rouge@menta.fr>
 

gcc/config/avr/avr.c

@@ -1784,7 +1784,8 @@ avr_function_arg_advance (CUMULATIVE_ARGS *cum, enum machine_mode mode,
      a function must not pass arguments in call-saved regs in order to get
      tail-called. */
   
-  if (cum->regno >= 0
+  if (cum->regno >= 8
+      && cum->nregs >= 0
       && !call_used_regs[cum->regno])
     {
       /* FIXME: We ship info on failing tail-call in struct machine_function.
@@ -1800,7 +1801,8 @@ avr_function_arg_advance (CUMULATIVE_ARGS *cum, enum machine_mode mode,
      user has fixed a GPR needed to pass an argument, an (implicit) function
      call would clobber that fixed register.  See PR45099 for an example.  */
   
-  if (cum->regno >= 0)
+  if (cum->regno >= 8
+      && cum->nregs >= 0)
     {
       int regno;