corrected again a regression bug in causality/scheduling: bad handling of tuples

src/causality.ml

@@ -118,6 +118,7 @@ module ExprDep = struct
 
   let is_read_var v = v.[0] = '#'
   let is_instance_var v = v.[0] = '!' || v.[0] = '?'
+  let is_call_instance_var v = v.[0] = '?'
   let is_ghost_var v = is_instance_var v || is_read_var v
 
   let undo_read_var id =

src/causality.mli

@@ -40,6 +40,7 @@ module ExprDep : sig
   val mk_return_instance_var : ident -> ident
   val mk_read_var : ident -> ident
   val is_instance_var : ident -> bool
+  val is_call_instance_var : ident -> bool
   val is_ghost_var : ident -> bool
   val is_read_var : ident -> bool
   val undo_instance_var : ident -> ident

src/scheduling.ml

@@ -30,7 +30,7 @@ open Scheduling_type
 (* Checks whether the currently scheduled variable [choice] is an output of a
    call, possibly among others *)
 let is_call_output choice g =
-  List.exists ExprDep.is_instance_var (IdentDepGraph.succ g choice)
+  List.exists ExprDep.is_call_instance_var (IdentDepGraph.succ g choice)
 
 (* Adds successors of [v] in graph [g] in [pending] or [frontier] sets, wrt
    [eq_equiv], then removes [v] from [g] *)
@@ -55,6 +55,7 @@ let next_element eq_equiv g sort call pending frontier =
     pending := p;
     frontier := f;
     call := is_call_output choice g;
+    (*if !call then Format.eprintf "call var@."*)
     add_successors eq_equiv g choice pending frontier;
     if not (ExprDep.is_ghost_var choice) then sort := [ choice ] :: !sort)
   else
@@ -62,6 +63,7 @@ let next_element eq_equiv g sort call pending frontier =
     (*Format.eprintf "-2-> %s@." choice;*)
     pending := ISet.remove choice !pending;
     add_successors eq_equiv g choice pending frontier;
+    (*if !call then Format.eprintf "call var@."*)
     if not (ExprDep.is_ghost_var choice) then
       sort :=
         if !call then (choice :: List.hd !sort) :: List.tl !sort
@@ -82,6 +84,7 @@ let topological_sort eq_equiv g =
     next_element eq_equiv g sorted call pending frontier
   done;
   IdentDepGraph.clear g;
+  (*List.iter (fun l -> Format.eprintf "(%a) " (fun fmt -> List.iter (fun v -> Format.pp_print_string fmt v)) l) !sorted;*)
   !sorted
 
 (* XXX: UNUSED *)