re PR target/77728 (Miscompilation multiple vector iteration on ARM)

re PR target/77728 (Miscompilation multiple vector iteration on ARM)

	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.

Co-Authored-By: Jakub Jelinek <jakub@redhat.com>
From-SVN: r247239