(***********************************************************************)
(* *)
(* TAToo *)
(* *)
(* Kim Nguyen, LRI UMR8623 *)
(* Université Paris-Sud & CNRS *)
(* *)
(* Copyright 2010-2013 Université Paris-Sud and Centre National de la *)
(* Recherche Scientifique. All rights reserved. This file is *)
(* distributed under the terms of the GNU Lesser General Public *)
(* License, with the special exception on linking described in file *)
(* ../LICENSE. *)
(* *)
(***********************************************************************)
INCLUDE "utils.ml"
open Format
open Misc
module Make (T : Tree.S) =
struct
module NodeSummary =
struct
(* Pack into an integer the result of the is_* and has_ predicates
for a given node *)
type t = int
let dummy = -1
(*
4444444444443210
4 -> kind
3 -> is_left
2 -> is_right
1 -> has_left
0 -> has_right
*)
let has_right (s : t) : bool =
Obj.magic (s land 1)
let has_left (s : t) : bool =
Obj.magic ((s lsr 1) land 1)
let is_right (s : t) : bool =
Obj.magic ((s lsr 2) land 1)
let is_left (s : t) : bool =
Obj.magic ((s lsr 3) land 1)
let kind (s : t) : Tree.NodeKind.t =
Obj.magic (s lsr 4)
let make is_left is_right has_left has_right kind =
((Obj.magic kind) lsl 4) lor
((int_of_bool is_left) lsl 3) lor
((int_of_bool is_right) lsl 2) lor
((int_of_bool has_left) lsl 1) lor
(int_of_bool has_right)
end
type node_status = {
sat : StateSet.t;
unsat : StateSet.t;
todo : Ata.TransList.t;
summary : NodeSummary.t;
}
(* Describe what is kept at each node for a run *)
module NodeStatus = Hcons.Make(struct
type t = node_status
let equal c d =
c == d ||
c.sat == d.sat &&
c.unsat == d.unsat &&
c.todo == d.todo &&
c.summary == d.summary
let hash c =
HASHINT4((c.sat.StateSet.id :> int),
(c.unsat.StateSet.id :> int),
(c.todo.Ata.TransList.id :> int),
c.summary)
end
)
let dummy_status =
NodeStatus.make { sat = StateSet.empty;
unsat = StateSet.empty;
todo = Ata.TransList.nil;
summary = NodeSummary.dummy;
}
type run = {
tree : T.t ;
(* The argument of the run *)
auto : Ata.t;
(* The automaton to be run *)
status : NodeStatus.t array;
(* A mapping from node preorders to NodeStatus *)
unstable : Bitvector.t;
(* A bitvector remembering whether a subtree is stable *)
mutable redo : bool;
(* A boolean indicating whether the run is incomplete *)
mutable pass : int;
(* The number of times this run was updated *)
mutable cache2 : Ata.TransList.t Cache.N2.t;
(* A cache from states * label to list of transitions *)
mutable cache4 : NodeStatus.t Cache.N4.t;
}
let pass r = r.pass
let stable r = not r.redo
let auto r = r.auto
let tree r = r.tree
let dummy_trl =
Ata.(TransList.cons
(Transition.make
(State.dummy,QNameSet.empty, Formula.false_))
TransList.nil)
let make auto tree =
let len = T.size tree in
{
tree = tree;
auto = auto;
status = Array.create len dummy_status;
unstable = Bitvector.create ~init:true len;
redo = true;
pass = 0;
cache2 = Cache.N2.create dummy_trl;
cache4 = Cache.N4.create dummy_status;
}
let get_status a i =
if i < 0 then dummy_status else Array.get a i
let unsafe_get_status a i =
if i < 0 then dummy_status else Array.unsafe_get a i
IFDEF HTMLTRACE
THEN
DEFINE TRACE(e) = (e)
ELSE
DEFINE TRACE(e) = ()
END
let html tree node i config msg =
let config = config.NodeStatus.node in
Html.trace (T.preorder tree node) i
"node: %i
%s
sat: %a
unsat: %a
todo: %around: %i
"
(T.preorder tree node)
msg
StateSet.print config.sat
StateSet.print config.unsat
(Ata.TransList.print ~sep:"
") config.todo i
let debug msg tree node i config =
let config = config.NodeStatus.node in
eprintf
"DEBUG:%s node: %i\nsat: %a\nunsat: %a\ntodo: %around: %i\n"
msg
(T.preorder tree node)
StateSet.print config.sat
StateSet.print config.unsat
(Ata.TransList.print ~sep:"\n") config.todo i
let get_trans cache2 auto tag states =
let trs =
Cache.N2.find cache2
(tag.QName.id :> int) (states.StateSet.id :> int)
in
if trs == dummy_trl then
let trs = Ata.get_trans auto tag states in
(Cache.N2.add
cache2
(tag.QName.id :> int)
(states.StateSet.id :> int) trs; trs)
else trs
let simplify_atom atom pos q { NodeStatus.node = status; _ } =
if (pos && StateSet.mem q status.sat)
|| ((not pos) && StateSet.mem q status.unsat) then Ata.Formula.true_
else if (pos && StateSet.mem q status.unsat)
|| ((not pos) && StateSet.mem q status.sat) then Ata.Formula.false_
else atom
let eval_form phi fcs nss ps ss summary =
let open Ata in
let rec loop phi =
begin match Formula.expr phi with
Boolean.True | Boolean.False -> phi
| Boolean.Atom (a, b) ->
begin
let open NodeSummary in
match a.Atom.node with
| Move (m, q) ->
let states = match m with
`First_child -> fcs
| `Next_sibling -> nss
| `Parent | `Previous_sibling -> ps
| `Stay -> ss
in simplify_atom phi b q states
| Is_first_child -> Formula.of_bool (b == is_left summary)
| Is_next_sibling -> Formula.of_bool (b == is_right summary)
| Is k -> Formula.of_bool (b == (k == kind summary))
| Has_first_child -> Formula.of_bool (b == has_left summary)
| Has_next_sibling -> Formula.of_bool (b == has_right summary)
end
| Boolean.And(phi1, phi2) -> Formula.and_ (loop phi1) (loop phi2)
| Boolean.Or (phi1, phi2) -> Formula.or_ (loop phi1) (loop phi2)
end
in
loop phi
type trivalent = False | True | Unknown
let or_ t1 t2 = match t1 with
False -> t2
| True -> True
| Unknown -> if t2 == True then True else Unknown
let and_ t1 t2 = match t1 with
False -> False
| True -> t2
| Unknown -> if t2 == False then False else Unknown
let of_bool = function false -> False | true -> True
let eval_form phi fcs nss ps ss summary =
let open Ata in
let rec loop phi =
begin match Formula.expr phi with
| Boolean.False -> False
| Boolean.True -> True
| Boolean.Atom (a, b) ->
begin
let open NodeSummary in
match a.Atom.node with
| Move (m, q) ->
let sum = match m with
`First_child -> fcs
| `Next_sibling -> nss
| `Parent | `Previous_sibling -> ps
| `Stay -> ss
in
if StateSet.mem q sum.NodeStatus.node.sat then of_bool b
else if StateSet.mem q sum.NodeStatus.node.unsat then of_bool (not b)
else Unknown
| Is_first_child -> of_bool (b == is_left summary)
| Is_next_sibling -> of_bool (b == is_right summary)
| Is k -> of_bool (b == (k == kind summary))
| Has_first_child -> of_bool (b == has_left summary)
| Has_next_sibling -> of_bool (b == has_right summary)
end
| Boolean.And(phi1, phi2) -> and_ (loop phi1) (loop phi2)
| Boolean.Or (phi1, phi2) -> or_ (loop phi1) (loop phi2)
end
in
loop phi
let eval_trans_aux cache4 fcs nss ps ss old_config =
let { sat = old_sat;
unsat = old_unsat;
todo = old_todo;
summary = old_summary } = old_config.NodeStatus.node
in
let sat, unsat, removed, kept, todo =
Ata.TransList.fold
(fun trs acc ->
let q, lab, phi = Ata.Transition.node trs in
let a_sat, a_unsat, a_rem, a_kept, a_todo = acc in
if StateSet.mem q a_sat || StateSet.mem q a_unsat then acc else
let phi_val =
eval_form phi fcs nss ps old_config old_summary
in
match phi_val with
| False -> a_sat, StateSet.add q a_unsat, StateSet.add q a_rem, a_kept, a_todo
| True -> StateSet.add q a_sat, a_unsat, StateSet.add q a_rem, a_kept, a_todo
| Unknown ->
(a_sat, a_unsat, a_rem, StateSet.add q a_kept, (Ata.TransList.cons trs a_todo))
) old_todo (old_sat, old_unsat, StateSet.empty, StateSet.empty, Ata.TransList.nil)
in
(* States that have been removed from the todo list and not kept are now
unsatisfiable *)
let unsat = StateSet.union unsat (StateSet.diff removed kept) in
(* States that were found once to be satisfiable remain so *)
let unsat = StateSet.diff unsat sat in
let new_config = NodeStatus.make { old_config.NodeStatus.node with sat; unsat; todo; } in
new_config
let eval_trans cache4 fcs nss ps ss =
let fcsid = (fcs.NodeStatus.id :> int) in
let nssid = (nss.NodeStatus.id :> int) in
let psid = (ps.NodeStatus.id :> int) in
let rec loop old_config =
let oid = (old_config.NodeStatus.id :> int) in
let res =
let res = Cache.N4.find cache4 oid fcsid nssid psid in
if res != dummy_status then res
else
let new_config =
eval_trans_aux cache4 fcs nss ps ss old_config
in
Cache.N4.add cache4 oid fcsid nssid psid new_config;
new_config
in
if res == old_config then res else loop res
in
loop ss
let top_down run =
let tree = run.tree in
let auto = run.auto in
let status = run.status in
let cache2 = run.cache2 in
let cache4 = run.cache4 in
let unstable = run.unstable in
let rec loop node =
let node_id = T.preorder tree node in
if node == T.nil || not (Bitvector.get unstable node_id) then false else begin
let parent = T.parent tree node in
let fc = T.first_child tree node in
let fc_id = T.preorder tree fc in
let ns = T.next_sibling tree node in
let ns_id = T.preorder tree ns in
let tag = T.tag tree node in
(* We enter the node from its parent *)
let status0 =
let c = unsafe_get_status status node_id in
if c == dummy_status then
(* first time we visit the node *)
let ltrs = get_trans cache2 auto tag (Ata.get_states auto) in
NodeStatus.make
{ sat = StateSet.empty;
unsat = Ata.get_starting_states auto;
todo = ltrs;
summary = NodeSummary.make
(node == T.first_child tree parent) (* is_left *)
(node == T.next_sibling tree parent) (* is_right *)
(fc != T.nil) (* has_left *)
(ns != T.nil) (* has_right *)
(T.kind tree node) (* kind *)
}
else c
in
TRACE(html tree node _i config0 "Entering node");
(* get the node_statuses for the first child, next sibling and parent *)
let ps = unsafe_get_status status (T.preorder tree parent) in
let fcs = unsafe_get_status status fc_id in
let nss = unsafe_get_status status ns_id in
(* evaluate the transitions with all this statuses *)
let status1 = eval_trans cache4 fcs nss ps status0 in
TRACE(html tree node _i config1 "Updating transitions");
(* update the cache if the status of the node changed *)
if status1 != status0 then status.(node_id) <- status1;
(* recursively traverse the first child *)
let unstable_left = loop fc in
(* here we re-enter the node from its first child,
get the new status of the first child *)
let fcs1 = unsafe_get_status status fc_id in
(* update the status *)
let status2 = eval_trans cache4 fcs1 nss ps status1 in
TRACE(html tree node _i config2 "Updating transitions (after first-child)");
if status2 != status1 then status.(node_id) <- status2;
let unstable_right = loop ns in
let nss1 = unsafe_get_status status ns_id in
let status3 = eval_trans cache4 fcs1 nss1 ps status2 in
TRACE(html tree node _i config3 "Updating transitions (after next-sibling)");
if status3 != status2 then status.(node_id) <- status3;
let unstable_self =
(* if either our left or right child is unstable or if we still have transitions
pending, the current node is unstable *)
unstable_left
|| unstable_right
|| Ata.TransList.nil != status3.NodeStatus.node.todo
in
Bitvector.unsafe_set unstable node_id unstable_self;
TRACE((if not unstable_self then
Html.finalize_node
node_id
_i
Ata.(StateSet.intersect config3.Config.node.sat auto.selection_states)));
unstable_self
end
in
run.redo <- loop (T.root tree);
run.pass <- run.pass + 1
(*
let stats run =
let count = ref 0 in
let len = Bitvector.length run.unstable in
for i = 0 to len - 1 do
if not (Bitvector.unsafe_get run.unstable i) then
incr count
done;
Logger.msg `STATS
"%i nodes over %i were skipped in iteration %i (%.2f %%), redo is: %b"
!count len run.pass (100. *. (float !count /. float len))
run.redo
let eval auto tree node =
let len = T.size tree in
let run = { config = Array.create len Ata.dummy_config;
unstable = Bitvector.create ~init:true len;
redo = true;
pass = 0
}
in
while run.redo do
run.redo <- false;
Ata.reset auto; (* prevents the .cache2 and .cache4 memoization tables from growing too much *)
run.redo <- top_down_run auto tree node run;
stats run;
run.pass <- run.pass + 1;
done;
at_exit (fun () -> Logger.msg `STATS "%i iterations" run.pass);
at_exit (fun () -> stats run);
let r = get_results auto tree node run.config in
TRACE(Html.gen_trace (module T : Tree.S with type t = T.t) (tree));
r
*)
let get_results run =
let cache = run.status in
let auto = run.auto in
let tree = run.tree in
let rec loop node acc =
if node == T.nil then acc
else
let acc0 = loop (T.next_sibling tree node) acc in
let acc1 = loop (T.first_child tree node) acc0 in
if Ata.(
StateSet.intersect
cache.(T.preorder tree node).NodeStatus.node.sat
(get_selecting_states auto)) then node::acc1
else acc1
in
loop (T.root tree) []
let get_full_results run =
let cache = run.status in
let auto = run.auto in
let tree = run.tree in
let res_mapper = Hashtbl.create MED_H_SIZE in
let () =
StateSet.iter
(fun q -> Hashtbl.add res_mapper q [])
(Ata.get_selecting_states auto)
in
let rec loop node =
if node != T.nil then
let () = loop (T.next_sibling tree node) in
let () = loop (T.first_child tree node) in
StateSet.iter
(fun q ->
try
let acc = Hashtbl.find res_mapper q in
Hashtbl.replace res_mapper q (node::acc)
with
Not_found -> ())
cache.(T.preorder tree node).NodeStatus.node.sat
in
loop (T.root tree);
StateSet.fold
(fun q acc -> (q, Hashtbl.find res_mapper q)::acc)
(Ata.get_selecting_states auto) []
let prepare_run run list =
let tree = run.tree in
let auto = run.auto in
let status = run.status in
let cache2 = run.cache2 in
List.iter (fun node ->
let parent = T.parent tree node in
let fc = T.first_child tree node in
let ns = T.next_sibling tree node in
let tag = T.tag tree node in
let status0 =
NodeStatus.make
{ sat = Ata.get_starting_states auto;
unsat = StateSet.empty;
todo = get_trans cache2 auto tag (Ata.get_states auto);
summary = NodeSummary.make
(node == T.first_child tree parent) (* is_left *)
(node == T.next_sibling tree parent) (* is_right *)
(fc != T.nil) (* has_left *)
(ns != T.nil) (* has_right *)
(T.kind tree node) (* kind *)
}
in
let node_id = T.preorder tree node in
status.(node_id) <- status0) list
let eval full auto tree nodes =
let run = make auto tree in
prepare_run run nodes;
while run.redo do
top_down run
done;
if full then `Full (get_full_results run)
else `Normal (get_results run)
let full_eval auto tree nodes =
match eval true auto tree nodes with
`Full l -> l
| _ -> assert false
let eval auto tree nodes =
match eval false auto tree nodes with
`Normal l -> l
| _ -> assert false
end