You re almost certain to badly damage the water-repellent coating, which is a polyurethane that is sprayed on in a thin film. And you might well snag the tents cords and zippers in the washer, tearing a seam. Dry out the tent entirely when you get home, and store in a loose, breathable bag. If the tent does get dirty, clean it with a damp sponge and a little soapy water.
Ivory soap is a good choice here.
Again, dry thoroughly. OK, you can breathe now.