wp_is_post_autosave()

wp_is_post_autosave( int|WP_Post $post ): int|false

function wp_is_post_autosave( $post ) {
	$post = wp_get_post_revision( $post );

	if ( ! $post ) {
		return false;
	}

	if ( str_contains( $post->post_name, "{$post->post_parent}-autosave" ) ) {
		return (int) $post->post_parent;
	}

	return false;
}