PR target/77728

	PR target/77728
	* config/aarch64/aarch64.c (struct aarch64_fn_arg_alignment): New
	type.
	(aarch64_function_arg_alignment): Return aarch64_fn_arg_alignment
	struct.  Ignore DECL_ALIGN of decls other than FIELD_DECL for
	the alignment computation, but return their maximum in warn_alignment.
	(aarch64_layout_arg): Adjust aarch64_function_arg_alignment caller.
	Emit a -Wpsabi note if warn_alignment is 16 bytes, but alignment
	is smaller.
	(aarch64_function_arg_boundary): Likewise.  Simplify using MIN/MAX.
	(aarch64_gimplify_va_arg_expr): Adjust aarch64_function_arg_alignment
	caller.
testsuite/
	* g++.dg/abi/pr77728-2.C: New test.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@247239 138bc75d-0d04-0410-961f-82ee72b054a4