It's not Smilax. Smilax has smooth edged leaves not toothed, it also has tendrils with which to grasp and climb. Smilax berries are also larger and darker, even black.
I have a weed (because it volunteered, I didn't plant it) much like the picture growing off my back deck. I think it is some type of vervain, botanical genus
Verbena, maybe
Verbena bonariensis. I haven't munched on it yet, nor have I fed it to any of the livestock. Plants for a future (
www.pfaf.org) has 4 species of verbena listed, all only marginally edible.