let update_at_label env l p =
try
let mem_lab = List.assoc l env.states in
let mem_here = mem_at env Clabels.Here in
let dov vi v_l p =
let v_here = get_var ~create:true mem_here vi in
D.subst v_l (F.var v_here) p
in Varinfo.Hashtbl.fold dov mem_lab.variables p
with Not_found -> p