| 1 |
type 'a obj = { id : int; mutable v : 'a }
|
| 2 |
|
| 3 |
type 'a t =
|
| 4 |
| True
|
| 5 |
| False
|
| 6 |
| Split of 'a obj * 'a t * 'a t * 'a t
|
| 7 |
|
| 8 |
let rec equal a b =
|
| 9 |
(a == b) ||
|
| 10 |
match (a,b) with
|
| 11 |
| Split (x1, p1,i1,n1), Split (x2, p2,i2,n2) ->
|
| 12 |
(x1.id = x2.id) && (equal p1 p2) & (equal i1 i2) &&
|
| 13 |
(equal n1 n2)
|
| 14 |
| _ -> false
|
| 15 |
|
| 16 |
let rec compare a b =
|
| 17 |
if (a == b) then 0
|
| 18 |
else match (a,b) with
|
| 19 |
| Split (x1, p1,i1,n1), Split (x2, p2,i2,n2) ->
|
| 20 |
if x1.id < x2.id then -1
|
| 21 |
else if x1.id > x2.id then 1
|
| 22 |
else let c = compare p1 p2 in if c <> 0 then c
|
| 23 |
else let c = compare i1 i2 in if c <> 0 then c
|
| 24 |
else compare n1 n2
|
| 25 |
| True,_ -> -1
|
| 26 |
| _, True -> 1
|
| 27 |
| False,_ -> -1
|
| 28 |
| _,False -> 1
|
| 29 |
|
| 30 |
let rec hash = function
|
| 31 |
| True -> 1
|
| 32 |
| False -> 2
|
| 33 |
| Split (x, p,i,n) ->
|
| 34 |
x.id + 17 * (hash p) + 257 * (hash i) + 16637 * (hash n)
|
| 35 |
|
| 36 |
let rec iter f = function
|
| 37 |
| Split (x, p,i,n) -> f x.v; iter f p; iter f i; iter f n
|
| 38 |
| _ -> ()
|
| 39 |
|
| 40 |
(* TODO: precompute hash value for Split node to have fast equality... *)
|
| 41 |
|
| 42 |
(*
|
| 43 |
let rec print f ppf = function
|
| 44 |
| True -> Format.fprintf ppf "True"
|
| 45 |
| False -> Format.fprintf ppf "False"
|
| 46 |
| Split (x, p,i,n) ->
|
| 47 |
Format.fprintf ppf "%a(@[%a,%a,%a@])"
|
| 48 |
f x.v (print f) p (print f) i (print f) n
|
| 49 |
*)
|
| 50 |
|
| 51 |
|
| 52 |
let rec print f ppf = function
|
| 53 |
| True -> Format.fprintf ppf "Any"
|
| 54 |
| False -> Format.fprintf ppf "Empty"
|
| 55 |
| Split (x, p,i, n) ->
|
| 56 |
(* Format.fprintf ppf "{%i}" x.id; *)
|
| 57 |
let flag = ref false in
|
| 58 |
let b () = if !flag then Format.fprintf ppf " | " else flag := true in
|
| 59 |
(match p with
|
| 60 |
| True -> b(); Format.fprintf ppf "%a" f x.v
|
| 61 |
| False -> ()
|
| 62 |
| _ -> b (); Format.fprintf ppf "%a & @[(%a)@]" f x.v (print f) p );
|
| 63 |
(match i with
|
| 64 |
| True -> assert false;
|
| 65 |
| False -> ()
|
| 66 |
| _ -> b(); print f ppf i);
|
| 67 |
(match n with
|
| 68 |
| True -> b (); Format.fprintf ppf "@[~%a@]" f x.v
|
| 69 |
| False -> ()
|
| 70 |
| _ -> b (); Format.fprintf ppf "@[~%a@] & @[(%a)@]" f x.v (print f) n)
|
| 71 |
|
| 72 |
|
| 73 |
|
| 74 |
let rec dump ppf = function
|
| 75 |
| True -> Format.fprintf ppf "True"
|
| 76 |
| False -> Format.fprintf ppf "False"
|
| 77 |
| Split (x, p,i,n) ->
|
| 78 |
Format.fprintf ppf "%i(@[%a,%a,%a@])"
|
| 79 |
x.id dump p dump i dump n
|
| 80 |
|
| 81 |
let rec dnf accu pos neg = function
|
| 82 |
| True -> (pos,neg) :: accu
|
| 83 |
| False -> accu
|
| 84 |
| Split (x, p,i,n) ->
|
| 85 |
let accu = dnf accu (x.v::pos) neg p in
|
| 86 |
let accu = dnf accu pos (x.v::neg) n in
|
| 87 |
let accu = dnf accu pos neg i in
|
| 88 |
accu
|
| 89 |
|
| 90 |
let dnf x = dnf [] [] [] x
|
| 91 |
|
| 92 |
let compute ~empty ~any ~cup ~cap ~diff ~atom b =
|
| 93 |
let rec aux = function
|
| 94 |
| True -> any
|
| 95 |
| False -> empty
|
| 96 |
| Split(x, p,i,n) ->
|
| 97 |
let p = cap (atom x.v) (aux p)
|
| 98 |
and i = aux i
|
| 99 |
and n = diff (aux p) (atom x.v) in
|
| 100 |
cup (cup p i) n
|
| 101 |
in
|
| 102 |
aux b
|
| 103 |
|
| 104 |
(* Invariants:
|
| 105 |
Split (x, pos,ign,neg) ==> (ign <> True);
|
| 106 |
(pos <> False or neg <> False)
|
| 107 |
|
| 108 |
Other meaningful invariant that could be enforced:
|
| 109 |
- pos <> neg
|
| 110 |
- no ``subsumption'' --> DONE (cf below)
|
| 111 |
*)
|
| 112 |
|
| 113 |
let split x pos ign neg =
|
| 114 |
if ign = True then True
|
| 115 |
else if (pos = False) && (neg = False) then ign
|
| 116 |
else Split (x, pos, ign, neg)
|
| 117 |
|
| 118 |
|
| 119 |
let ( !! ) x = Split (x, True, False, False)
|
| 120 |
|
| 121 |
let empty = False
|
| 122 |
let any = True
|
| 123 |
|
| 124 |
let rec simplify a l =
|
| 125 |
(* Format.fprintf Format.std_formatter "simplify %a <=" dump a;
|
| 126 |
List.iter (fun b -> Format.fprintf Format.std_formatter " %a" dump b) l;
|
| 127 |
Format.fprintf Format.std_formatter "@\n";
|
| 128 |
*)
|
| 129 |
if (a = False) then False else simpl_aux1 a [] l
|
| 130 |
and simpl_aux1 a accu = function
|
| 131 |
| [] ->
|
| 132 |
if accu = [] then a else
|
| 133 |
(match a with
|
| 134 |
| True -> True
|
| 135 |
| False -> assert false
|
| 136 |
| Split (x,p,i,n) -> simpl_aux2 x p i n [] [] [] accu)
|
| 137 |
| False :: l -> simpl_aux1 a accu l
|
| 138 |
| True :: l -> False
|
| 139 |
| b :: l -> if a == b then False else simpl_aux1 a (b::accu) l
|
| 140 |
and simpl_aux2 x p i n ap ai an = function
|
| 141 |
| [] -> split x (simplify p ap) (simplify i ai) (simplify n an)
|
| 142 |
| (Split (x2,p2,i2,n2) as b) :: l ->
|
| 143 |
if x2.id < x.id then
|
| 144 |
simpl_aux3 x p i n ap ai an l i2
|
| 145 |
else if x.id < x2.id then
|
| 146 |
simpl_aux2 x p i n (b :: ap) (b :: ai) (b :: an) l
|
| 147 |
else
|
| 148 |
simpl_aux2 x p i n (p2 :: i2 :: ap) (i2 :: ai) (n2 :: i2 :: an) l
|
| 149 |
| _ -> assert false
|
| 150 |
and simpl_aux3 x p i n ap ai an l = function
|
| 151 |
| False -> simpl_aux2 x p i n ap ai an l
|
| 152 |
| True -> assert false
|
| 153 |
| Split (x2,p2,i2,n2) as b ->
|
| 154 |
if x2.id < x.id then
|
| 155 |
simpl_aux3 x p i n ap ai an l i2
|
| 156 |
else if x.id < x2.id then
|
| 157 |
simpl_aux2 x p i n (b :: ap) (b :: ai) (b :: an) l
|
| 158 |
else
|
| 159 |
simpl_aux2 x p i n (p2 :: i2 :: ap) (i2 :: ai) (n2 :: i2 :: an) l
|
| 160 |
|
| 161 |
let split x p i n =
|
| 162 |
split x (simplify p [i]) i (simplify n [i])
|
| 163 |
|
| 164 |
let rec ( ++ ) a b =
|
| 165 |
if a == b then a
|
| 166 |
else match (a,b) with
|
| 167 |
| True, _ | _, True -> True
|
| 168 |
| False, a | a, False -> a
|
| 169 |
| Split (x1, p1,i1,n1), Split (x2, p2,i2,n2) ->
|
| 170 |
if x1.id = x2.id then
|
| 171 |
split x1 (p1 ++ p2) (i1 ++ i2) (n1 ++ n2)
|
| 172 |
else if x1.id < x2.id then
|
| 173 |
split x1 p1 (i1 ++ b) n1
|
| 174 |
else
|
| 175 |
split x2 p2 (i2 ++ a) n2
|
| 176 |
|
| 177 |
|
| 178 |
(* TODO: optimize the cup with 3 arguments ? *)
|
| 179 |
|
| 180 |
let rec ( ** ) a b =
|
| 181 |
if a == b then a
|
| 182 |
else match (a,b) with
|
| 183 |
| True, a | a, True -> a
|
| 184 |
| False, _ | _, False -> False
|
| 185 |
| Split (x1, p1,i1,n1), Split (x2, p2,i2,n2) ->
|
| 186 |
if x1.id = x2.id then
|
| 187 |
split x1
|
| 188 |
((p1 ** p2) ++ (p1 ** i2) ++ (p2 ** i1))
|
| 189 |
(i1 ** i2)
|
| 190 |
((n1 ** n2) ++ (n1 ** i2) ++ (n2 ** i1))
|
| 191 |
else if x1.id < x2.id then
|
| 192 |
split x1 (p1 ** b) (i1 ** b) (n1 ** b)
|
| 193 |
else
|
| 194 |
split x2 (p2 ** a) (i2 ** a) (n2 ** a)
|
| 195 |
|
| 196 |
let rec ( // ) a b =
|
| 197 |
if a == b then False
|
| 198 |
else match (a,b) with
|
| 199 |
| False,_ | _, True -> False
|
| 200 |
| a, False -> a
|
| 201 |
| True, Split (x2, p2,i2,n2) ->
|
| 202 |
let i = True // i2 in
|
| 203 |
split x2 (i // p2) False (i // n2)
|
| 204 |
| Split (x1, p1,i1,n1), Split (x2, p2,i2,n2) ->
|
| 205 |
if x1.id = x2.id then
|
| 206 |
let i = i1 // i2 in
|
| 207 |
split x1
|
| 208 |
((p1 // p2 // i2) ++ (i // p2))
|
| 209 |
False
|
| 210 |
((n1 // n2 // i2) ++ (i // n2))
|
| 211 |
else if x1.id < x2.id then
|
| 212 |
split x1 (p1 // b) (i1 // b) (n1 // b)
|
| 213 |
else
|
| 214 |
let i = a // i2 in
|
| 215 |
split x2 (i // p2) False (i // n2)
|