As long as the root is OK it will grow. It is fine under the snow, in fact the snow will protect it. After the snow goes and you can get to it carefully unwind from the plant from the broken trellis. Have a new support structure ready--trellis or whatever you are going to use. Set it in and tie the vines to the trellis with a soft material.Cloth, an old nylon stocking or soft twine.

I like the velcro tape for tieing plants. It is soft on the inside and has the velcro hooks on the outside and is green so it becomes almost invisible. It is easy to remove when it's no longer needed and is reusable.

If there are any broken pieces cut them off below the break. Watch and see if there are any dead canes that don't leaf out later and cut them out too. When it leafs out give it a dose of fertilizer and it should be fine