We went to Wagamama in Birmingham for our 'adopted' son/ little brother's birthday as is becoming a tradition and I just had to say how much I like them.
On their website they list which dishes can be made gluten free and indeed do the same for a whole host of other allergens. Once you get to the restaurant you tell them you want the gluten free menu and they bring a book that lists all the allergens, dishes you can have and what had to be removed to make it safe.. then you order say number 26 no seasoning and you get a gluten free version. I do wish more places would do that. Apart from the occasional replacement of wheat noodles with rice ones they don't do any additions to dishes so some of them end up pretty plain but there are still a better selection than most places and if you have more than one allergy you can just cross check several lists.
The second reason I love them is that they bring the kids dishes FIRST as standard. You have no idea how many brownie points they score for that one, it seems standard in this country to bring the kids dishes last which is insane as they want their food colder than adults (and it has to start hot or it isn't cooked!) and they don't find waiting easy when hungry particularly if others have food plus you need to cut it up for them if they are small which means your food goes cold. We are so fed up with this we have started putting in complaints at anywhere that does it and Wagamama's is one of the few we haven't had to !!