[ast2C] store old values of variables used in the pre construct

src/cprint.ml

@@ -41,7 +41,7 @@ let cp_prototype fmt (node, h): unit =
   | None -> failwith "This should not happend!"
   | Some nst ->
       begin
-        Format.fprintf fmt "void %s (%s *state, %a);\n"
+        Format.fprintf fmt "void %s (%s *state, %a)"
           node.n_name
           nst.nt_name
           cp_varlist (snd node.n_inputs)
@@ -49,9 +49,33 @@ let cp_prototype fmt (node, h): unit =
 
 let rec cp_prototypes fmt (nodes, h) =
   match nodes with
-  | [] -> Format.fprintf fmt "\n\n"
+  | [] -> ()
   | node :: nodes ->
-      Format.fprintf fmt "%a%a"
+      Format.fprintf fmt "%a;\n%a"
         cp_prototype (node, h)
         cp_prototypes (nodes, h)
 
+(** The ollowing function prints the code to remember previous values of
+  * variables used with the pre construct. *)
+let cp_prevars fmt (node, h) =
+  let node_st = Hashtbl.find h node.n_name in
+  List.iter
+    (fun v -> (** Note that «dst_array = src_array» should hold. *)
+      let (src_array, src_idx) = Hashtbl.find node_st.nt_map (v, false) in
+      let (dst_array, dst_idx) = Hashtbl.find node_st.nt_map (v, true) in
+      Format.fprintf fmt "\t%s[%d] = %s[%d];\n"
+        dst_array dst_idx src_array src_idx)
+    node_st.nt_prevars
+
+let rec cp_node fmt (node, h) =
+  Format.fprintf fmt "%a\n{\nTODO...\n%a}\n"
+    cp_prototype (node, h)
+    cp_prevars (node, h)
+
+let rec cp_nodes fmt (nodes, h) =
+  match nodes with
+  | [] -> ()
+  | node :: nodes ->
+      Format.fprintf fmt "%a\n%a"
+        cp_node (node, h)
+        cp_nodes (nodes, h)