i386: Fix assert in ix86_function_arg [PR105970]

The mode of pointer argument should equal ptr_mode, not Pmode.

2022-06-17  Uroš Bizjak  <ubizjak@gmail.com>

gcc/ChangeLog:

	PR target/105970
	* config/i386/i386.cc (ix86_function_arg): Assert that
	the mode of pointer argumet is equal to ptr_mode, not Pmode.

gcc/testsuite/ChangeLog:

	PR target/105970
	* gcc.target/i386/pr105970.c: New test.

gcc/config/i386/i386.cc

@@ -3348,7 +3348,7 @@ ix86_function_arg (cumulative_args_t cum_v, const function_arg_info &arg)
       if (POINTER_TYPE_P (arg.type))
 	{
 	  /* This is the pointer argument.  */
-	  gcc_assert (TYPE_MODE (arg.type) == Pmode);
+	  gcc_assert (TYPE_MODE (arg.type) == ptr_mode);
 	  /* It is at -WORD(AP) in the current frame in interrupt and
 	     exception handlers.  */
 	  reg = plus_constant (Pmode, arg_pointer_rtx, -UNITS_PER_WORD);

gcc/testsuite/gcc.target/i386/pr105970.c

@@ -0,0 +1,6 @@
+/* PR target/105970 */
+/* { dg-do compile { target { ! ia32 } } } */
+/* { dg-require-effective-target maybe_x32 } */
+/* { dg-options "-mx32 -mgeneral-regs-only -maddress-mode=long" } */
+
+#include "../../gcc.dg/torture/pr68037-1.c"