In reply to Ian Parsons:
steff is correct, Bavarian dialect version of hilft (to help, 3ps).
"Huift nix" can sometimes mean that something is not beneficial in a given situation (as in Aspirin "huift nix" against a broken leg).
More likely, though, is a second connotation, where it is used to indicate that nothing else can be done to improve the current situation, so that one might as well start the job at hand without further ado (as in: Can't find a way get that pro in. "Huift nix", might as well start climbing without...)
CB