[wp] added post-effects to global assigns

src/plugins/wp/cfgWP.ml

@@ -90,7 +90,7 @@ struct
   (* Authorized written region from an assigns specification *)
   type effect = {
     e_pid : P.t ; (* Assign Property *)
-    e_kind : a_kind ; (* Requires post effects (in case of loop-assigns) *)
+    e_post : bool ; (* Requires post effects (loop-assigns or post-assigns) *)
     e_label : c_label ; (* scope for collection *)
     e_valid : L.sigma ; (* sigma where locations are filtered for validity *)
     e_region : L.region ; (* expected from spec *)
@@ -444,21 +444,23 @@ struct
         ainfo.a_assigns
     in match authorized_region with
     | None -> None
-    | Some region -> Some {
-        e_pid = pid ;
-        e_kind = ainfo.a_kind ;
-        e_label = from ;
-        e_valid = sigma ;
-        e_region = region ;
-        e_warn = Warning.Set.empty ;
-      }
+    | Some region ->
+        let post = match ainfo.a_kind with
+          | LoopAssigns -> true
+          | StmtAssigns -> NormAtLabels.has_postassigns ainfo.a_assigns
+        in Some {
+          e_pid = pid ;
+          e_post = post ;
+          e_label = from ;
+          e_valid = sigma ;
+          e_region = region ;
+          e_warn = Warning.Set.empty ;
+        }
 
   let cc_posteffect e vcs =
-    match e.e_kind with
-    | StmtAssigns -> vcs
-    | LoopAssigns ->
-        let vc = { empty_vc with vars = L.vars e.e_region } in
-        Gmap.add (Gposteffect e.e_pid) (Splitter.singleton vc) vcs
+    if not e.e_post then vcs else
+      let vc = { empty_vc with vars = L.vars e.e_region } in
+      Gmap.add (Gposteffect e.e_pid) (Splitter.singleton vc) vcs
 
   (* -------------------------------------------------------------------------- *)
   (* --- WP RULES : adding axioms, hypotheses and goals                     --- *)
@@ -549,14 +551,13 @@ struct
              vars = xs }
          in
          let group =
-           match e.e_kind with
-           | StmtAssigns ->
-               Splitter.singleton (setup empty_vc)
-           | LoopAssigns ->
-               try Splitter.map setup (Gmap.find (Gposteffect e.e_pid) vcs)
-               with Not_found ->
-                 Wp_parameters.fatal "Missing post-effect for %a"
-                   WpPropId.pretty e.e_pid
+           if not e.e_post then
+             Splitter.singleton (setup empty_vc)
+           else
+             try Splitter.map setup (Gmap.find (Gposteffect e.e_pid) vcs)
+             with Not_found ->
+               Wp_parameters.fatal "Missing post-effect for %a"
+                 WpPropId.pretty e.e_pid
          in
          let target = match sloc with
            | None -> Gprop e.e_pid

src/plugins/wp/clabels.ml

@@ -74,6 +74,11 @@ let of_logic = function
   | BuiltinLabel LoopEntry -> loopentry
   | StmtLabel s -> stmt !s
 
+let is_post = function
+  | BuiltinLabel Post -> true
+  | FormalLabel a -> a = post
+  | _ -> false
+
 let name = function FormalLabel a -> a | _ -> ""
 
 let lookup labels a =

src/plugins/wp/clabels.mli

@@ -65,6 +65,9 @@ val of_logic : Cil_types.logic_label -> c_label
     labels. Ambiguous labels are: Old, LoopEntry and LoopCurrent, since
     they points to different program points dependending on the context. *)
 
+val is_post : Cil_types.logic_label -> bool
+(** Checks whether the logic-label is [Post] or [to_logic post] *)
+
 val pretty : Format.formatter -> c_label -> unit
 
 open Cil_types

src/plugins/wp/normAtLabels.ml

@@ -210,9 +210,27 @@ let preproc_assigns labels asgns =
   let visitor = new norm_at labels in
   List.map (Visitor.visitFramacFrom visitor) asgns
 
+let has_postassigns = function
+  | WritesAny -> false
+  | Writes froms ->
+      let exception HAS_POST in
+      let visitor = new norm_at (fun l ->
+          if Clabels.is_post l then raise HAS_POST
+          else Clabels.of_logic l
+        ) in
+      try
+        List.iter
+          (fun fr -> ignore @@ Visitor.visitFramacFrom visitor fr)
+          froms ;
+        false
+      with HAS_POST ->
+        true
+
 let catch_label_error ex txt1 txt2 = match ex with
   | LabelError lab ->
       Wp_parameters.warning
         "Unexpected label %a in %s : ignored %s"
         Wp_error.pp_logic_label lab txt1 txt2
   | _ -> raise ex
+
+(* -------------------------------------------------------------------------- *)

src/plugins/wp/normAtLabels.mli

@@ -42,5 +42,5 @@ val labels_predicate : (logic_label * logic_label) list -> label_mapping
 val labels_axiom : label_mapping
 
 val preproc_annot : label_mapping -> predicate -> predicate
-
 val preproc_assigns : label_mapping -> from list -> from list
+val has_postassigns : assigns -> bool