calls: Fix up TYPE_NO_NAMED_ARGS_STDARG_P handling [PR107453]

calls: Fix up TYPE_NO_NAMED_ARGS_STDARG_P handling [PR107453]

On powerpc64le-linux, the following patch fixes
-FAIL: gcc.dg/c2x-stdarg-4.c execution test
-FAIL: gcc.dg/torture/c2x-stdarg-split-1a.c   -O0  execution test
-FAIL: gcc.dg/torture/c2x-stdarg-split-1a.c   -O1  execution test
-FAIL: gcc.dg/torture/c2x-stdarg-split-1a.c   -O2  execution test
-FAIL: gcc.dg/torture/c2x-stdarg-split-1a.c   -O2 -flto -fno-use-linker-plugin -flto-partition=none  execution test
-FAIL: gcc.dg/torture/c2x-stdarg-split-1a.c   -O2 -flto -fuse-linker-plugin -fno-fat-lto-objects  execution test
-FAIL: gcc.dg/torture/c2x-stdarg-split-1a.c   -O3 -g  execution test
-FAIL: gcc.dg/torture/c2x-stdarg-split-1a.c   -Os  execution test
The problem is mismatch between the caller and callee side.
On the callee side, we do:
  /* NAMED_ARG is a misnomer.  We really mean 'non-variadic'. */
  if (!cfun->stdarg)
    data->arg.named = 1;  /* No variadic parms.  */
  else if (DECL_CHAIN (parm))
    data->arg.named = 1;  /* Not the last non-variadic parm. */
  else if (targetm.calls.strict_argument_naming (all->args_so_far))
    data->arg.named = 1;  /* Only variadic ones are unnamed.  */
  else
    data->arg.named = 0;  /* Treat as variadic.  */
which is later passed to the target hooks to determine if a particular
argument is named or not.  Now, cfun->stdarg is determined from the stdarg_p
call, which for the new C2X TYPE_NO_NAMED_ARGS_STDARG_P function types
(rettype fn (...)) returns true.  Such functions have no named arguments,
so data->arg.named will be 0 in function.cc.  But on the caller side,
as TYPE_NO_NAMED_ARGS_STDARG_P function types have TYPE_ARG_TYPES NULL,
we instead treat those calls as unprototyped even when they are prototyped
- /* If we know nothing, treat all args as named.  */ n_named_args = num_actuals;
in 2 spots.  We need to treat the TYPE_NO_NAMED_ARGS_STDARG_P cases as
prototyped with no named arguments.

2023-01-09  Jakub Jelinek  <jakub@redhat.com>

	PR target/107453
	* calls.cc (expand_call): For calls with
	TYPE_NO_NAMED_ARGS_STDARG_P (funtype) use zero for n_named_args.
	Formatting fix.