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lustrec / src / mutation.ml @ bde99c3f

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open LustreSpec
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open Corelang
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open Log
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open Format
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6
let random_seed = ref 0
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let threshold_delay = 95
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let threshold_inc_int = 97
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let threshold_dec_int = 97
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let threshold_random_int = 96
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let threshold_switch_int = 100 (* not implemented yet *)
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let threshold_random_float = 100 (* not used yet *)
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let threshold_negate_bool_var = 95
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let threshold_arith_op = 95
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let threshold_rel_op = 95
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let threshold_bool_op = 95
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let int_consts = ref []
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let rename_app id = 
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  if !Options.no_mutation_suffix then
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    id
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  else
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    id ^ "_mutant"
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(************************************************************************************)
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(*                    Gathering constants in the code                               *)
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(************************************************************************************)
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module IntSet = Set.Make (struct type t = int let compare = compare end)
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module OpCount = Mmap.Make (struct type t = string let compare = compare end)
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type records = {
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  consts: IntSet.t;
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  nb_boolexpr: int;
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  nb_pre: int;
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  nb_op: int OpCount.t;
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}
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let arith_op = ["+" ; "-" ; "*" ; "/"] 
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let bool_op = ["&&"; "||"; "xor";  "impl"] 
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let rel_op = ["<" ; "<=" ; ">" ; ">=" ; "!=" ; "=" ] 
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let ops = arith_op @ bool_op @ rel_op
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let all_ops = "not" :: ops
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let empty_records = 
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  {consts=IntSet.empty; nb_boolexpr=0; nb_pre=0; nb_op=OpCount.empty}
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let records = ref empty_records
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let merge_records records_list = 
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  let merge_record r1 r2 =
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    {
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      consts = IntSet.union r1.consts r2.consts;
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      nb_boolexpr = r1.nb_boolexpr + r2.nb_boolexpr;
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      nb_pre = r1.nb_pre + r2.nb_pre;
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      nb_op = OpCount.merge (fun op r1opt r2opt ->
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	match r1opt, r2opt with
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	| None, _ -> r2opt
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	| _, None -> r1opt
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	| Some x, Some y -> Some (x+y)
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      ) r1.nb_op r2.nb_op 
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    }
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  in
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  List.fold_left merge_record empty_records records_list
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let compute_records_const_value c =
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  match c with
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  | Const_int i -> {empty_records with consts = IntSet.singleton i}
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  | _ -> empty_records
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let rec compute_records_expr expr =
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  let boolexpr = 
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    if (Types.repr expr.expr_type).Types.tdesc = Types.Tbool then
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      {empty_records with nb_boolexpr = 1}
78
    else
79
      empty_records
80
  in
81
  let subrec = 
82
    match expr.expr_desc with
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    | Expr_const c -> compute_records_const_value c
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    | Expr_tuple l -> merge_records (List.map compute_records_expr l)
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    | Expr_ite (i,t,e) -> 
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      merge_records (List.map compute_records_expr [i;t;e])
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    | Expr_arrow (e1, e2) ->       
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      merge_records (List.map compute_records_expr [e1;e2])
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    | Expr_pre e -> 
90
      merge_records (
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	({empty_records with nb_pre = 1})
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	::[compute_records_expr e])
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    | Expr_appl (op_id, args, r) -> 
94
      if List.mem op_id ops then
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	merge_records (
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	  ({empty_records with nb_op = OpCount.singleton op_id 1})
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	  ::[compute_records_expr args])
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      else
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	compute_records_expr args
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    | _ -> empty_records
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  in
102
  merge_records [boolexpr;subrec]
103

    
104
let compute_records_eq eq = compute_records_expr eq.eq_rhs
105

    
106
let compute_records_node nd = 
107
  merge_records (List.map compute_records_eq (get_node_eqs nd))
108

    
109
let compute_records_top_decl td =
110
  match td.top_decl_desc with
111
  | Node nd -> compute_records_node nd
112
  | Const cst -> compute_records_const_value cst.const_value
113
  | _ -> empty_records
114

    
115
let compute_records prog = 
116
  merge_records (List.map compute_records_top_decl prog)
117

    
118
(*****************************************************************)
119
(*                  Random mutation                              *)
120
(*****************************************************************)
121

    
122
let check_mut e1 e2 =
123
  let rec eq e1 e2 =
124
    match e1.expr_desc, e2.expr_desc with
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    | Expr_const c1, Expr_const c2 -> c1 = c2
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    | Expr_ident id1, Expr_ident id2 -> id1 = id2
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    | Expr_tuple el1, Expr_tuple el2 -> List.length el1 = List.length el2 && List.for_all2 eq el1 el2
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    | Expr_ite (i1, t1, e1), Expr_ite (i2, t2, e2) -> eq i1 i2 && eq t1 t2 && eq e1 e2
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    | Expr_arrow (x1, y1), Expr_arrow (x2, y2) -> eq x1 x2 && eq y1 y2
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    | Expr_pre e1, Expr_pre e2 -> eq e1 e2
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    | Expr_appl (id1, e1, _), Expr_appl (id2, e2, _) -> id1 = id2 && eq e1 e2
132
  | _ -> false
133
  in
134
  if not (eq e1 e2) then
135
    Some (e1, e2)
136
  else
137
    None
138

    
139
let mk_cst_expr c = mkexpr Location.dummy_loc (Expr_const c)
140

    
141
let rdm_mutate_int i = 
142
  if Random.int 100 > threshold_inc_int then
143
    i+1
144
  else if Random.int 100 > threshold_dec_int then
145
    i-1
146
  else if Random.int 100 > threshold_random_int then
147
    Random.int 10
148
  else if Random.int 100 > threshold_switch_int then
149
    let idx = Random.int (List.length !int_consts) in
150
    List.nth !int_consts idx
151
  else
152
    i
153
  
154
let rdm_mutate_real r =
155
  if Random.int 100 > threshold_random_float then
156
    (* interval [0, bound] for random values *)
157
    let bound = 10 in
158
    (* max number of digits after comma *)
159
    let digits = 5 in
160
    (* number of digits after comma *)
161
    let shift = Random.int (digits + 1) in
162
    let eshift = 10. ** (float_of_int shift) in
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    let i = Random.int (1 + bound * (int_of_float eshift)) in
164
    let f = float_of_int i /. eshift in
165
    (Num.num_of_int i, shift, string_of_float f)
166
  else 
167
    r
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169
let rdm_mutate_op op = 
170
match op with
171
| "+" | "-" | "*" | "/" when Random.int 100 > threshold_arith_op ->
172
  let filtered = List.filter (fun x -> x <> op) ["+"; "-"; "*"; "/"] in
173
  List.nth filtered (Random.int 3)
174
| "&&" | "||" | "xor" | "impl" when Random.int 100 > threshold_bool_op ->
175
  let filtered = List.filter (fun x -> x <> op) ["&&"; "||"; "xor"; "impl"] in
176
  List.nth filtered (Random.int 3)
177
| "<" | "<=" | ">" | ">=" | "!=" | "=" when Random.int 100 > threshold_rel_op ->
178
  let filtered = List.filter (fun x -> x <> op) ["<"; "<="; ">"; ">="; "!="; "="] in
179
  List.nth filtered (Random.int 5)
180
| _ -> op
181

    
182

    
183
let rdm_mutate_var expr = 
184
  match (Types.repr expr.expr_type).Types.tdesc with 
185
  | Types.Tbool ->
186
    (* if Random.int 100 > threshold_negate_bool_var then *)
187
    let new_e = mkpredef_call expr.expr_loc "not" [expr] in
188
    Some (expr, new_e), new_e
189
    (* else  *)
190
    (*   expr *)
191
  | _ -> None, expr
192
    
193
let rdm_mutate_pre orig_expr = 
194
  let new_e = Expr_pre orig_expr in
195
  Some (orig_expr, {orig_expr with expr_desc = new_e}), new_e
196

    
197

    
198
let rdm_mutate_const_value c =
199
  match c with
200
  | Const_int i -> Const_int (rdm_mutate_int i)
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  | Const_real (n, i, s) -> let (n', i', s') = rdm_mutate_real (n, i, s) in Const_real (n', i', s')
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  | Const_array _
203
  | Const_string _
204
  | Const_struct _
205
  | Const_tag _ -> c
206

    
207
let rdm_mutate_const c =
208
  let new_const = rdm_mutate_const_value c.const_value in
209
  let mut = check_mut (mk_cst_expr c.const_value) (mk_cst_expr new_const) in
210
  mut, { c with const_value = new_const }
211

    
212

    
213
let select_in_list list rdm_mutate_elem = 
214
  let selected = Random.int (List.length list) in
215
  let mutation_opt, new_list, _ = 
216
    List.fold_right
217
      (fun elem (mutation_opt, res, cpt) -> if cpt = selected then 
218
	  let mutation, new_elem = rdm_mutate_elem elem in
219
	  Some mutation, new_elem::res, cpt+1  else mutation_opt, elem::res, cpt+1)
220
      list 
221
      (None, [], 0)
222
  in
223
  match mutation_opt with
224
  | Some mut -> mut, new_list
225
  | _ -> assert false
226

    
227

    
228
let rec rdm_mutate_expr expr =
229
  let mk_e d = { expr with expr_desc = d } in
230
  match expr.expr_desc with
231
  | Expr_ident id -> rdm_mutate_var expr
232
  | Expr_const c -> 
233
    let new_const = rdm_mutate_const_value c in 
234
    let mut = check_mut (mk_cst_expr c) (mk_cst_expr new_const) in
235
    mut, mk_e (Expr_const new_const)
236
  | Expr_tuple l -> 
237
    let mut, l' = select_in_list l rdm_mutate_expr in
238
    mut, mk_e (Expr_tuple l')
239
  | Expr_ite (i,t,e) -> 
240
    let mut, [i'; t'; e'] = select_in_list [i; t; e] rdm_mutate_expr in
241
    mut, mk_e (Expr_ite (i', t', e'))
242
  | Expr_arrow (e1, e2) -> 
243
    let mut, [e1'; e2'] = select_in_list [e1; e2] rdm_mutate_expr in
244
    mut, mk_e (Expr_arrow (e1', e2'))
245
  | Expr_pre e -> 
246
    let select_pre = Random.bool () in
247
    if select_pre then
248
      let mut, new_expr = rdm_mutate_pre expr in
249
      mut, mk_e new_expr
250
    else
251
      let mut, e' = rdm_mutate_expr e in
252
      mut, mk_e (Expr_pre e')
253
  | Expr_appl (op_id, args, r) -> 
254
    let select_op = Random.bool () in
255
    if select_op then
256
      let new_op_id = rdm_mutate_op op_id in
257
      let new_e = mk_e (Expr_appl (new_op_id, args, r)) in
258
      let mut = check_mut expr new_e in
259
      mut, new_e
260
    else
261
      let mut, new_args = rdm_mutate_expr args in
262
      mut, mk_e (Expr_appl (op_id, new_args, r))
263
  (* Other constructs are kept.
264
  | Expr_fby of expr * expr
265
  | Expr_array of expr list
266
  | Expr_access of expr * Dimension.dim_expr
267
  | Expr_power of expr * Dimension.dim_expr
268
  | Expr_when of expr * ident * label
269
  | Expr_merge of ident * (label * expr) list
270
  | Expr_uclock of expr * int
271
  | Expr_dclock of expr * int
272
  | Expr_phclock of expr * rat *)
273
   | _ -> None, expr
274
  
275

    
276
let rdm_mutate_eq eq =
277
  let mutation, new_rhs = rdm_mutate_expr eq.eq_rhs in
278
  mutation, { eq with eq_rhs = new_rhs }
279

    
280
let rnd_mutate_stmt stmt =
281
  match stmt with
282
  | Eq eq   -> let mut, new_eq = rdm_mutate_eq eq in
283
		 report ~level:1 
284
		   (fun fmt -> fprintf fmt "mutation: %a becomes %a@." 
285
		     Printers.pp_node_eq eq
286
		     Printers.pp_node_eq new_eq);
287
		 mut, Eq new_eq 
288
  | Aut aut -> assert false
289

    
290
let rdm_mutate_node nd = 
291
  let mutation, new_node_stmts =       
292
    select_in_list 
293
      nd.node_stmts rnd_mutate_stmt
294
  in
295
  mutation, { nd with node_stmts = new_node_stmts }
296

    
297
let rdm_mutate_top_decl td =
298
  match td.top_decl_desc with
299
  | Node nd -> 
300
    let mutation, new_node = rdm_mutate_node nd in 
301
    mutation, { td with top_decl_desc = Node new_node}
302
  | Const cst -> 
303
    let mut, new_cst = rdm_mutate_const cst in
304
    mut, { td with top_decl_desc = Const new_cst }
305
  | _ -> None, td
306
    
307
(* Create a single mutant with the provided random seed *)
308
let rdm_mutate_prog prog = 
309
  select_in_list prog rdm_mutate_top_decl
310

    
311
let rdm_mutate nb prog = 
312
  let rec iterate nb res =
313
    incr random_seed;
314
    if nb <= 0 then
315
      res
316
    else (
317
      Random.init !random_seed;
318
      let mutation, new_mutant = rdm_mutate_prog prog in
319
      match mutation with
320
	None -> iterate nb res 
321
      | Some mutation -> ( 
322
	if List.mem_assoc mutation res then (
323
	  iterate nb res
324
	)
325
	else (
326
	  report ~level:1 (fun fmt -> fprintf fmt "%i mutants remaining@." nb); 
327
	  iterate (nb-1) ((mutation, new_mutant)::res)
328
	)
329
      )
330
    )
331
  in
332
  iterate nb []
333

    
334

    
335
(*****************************************************************)
336
(*                  Random mutation                              *)
337
(*****************************************************************)
338

    
339
type mutant_t = Boolexpr of int | Pre of int | Op of string * int * string | IncrIntCst of int | DecrIntCst of int | SwitchIntCst of int * int 
340

    
341
let target : mutant_t option ref = ref None
342

    
343
let print_directive fmt d =
344
  match d with
345
  | Pre n -> Format.fprintf fmt "pre %i" n
346
  | Boolexpr n -> Format.fprintf fmt "boolexpr %i" n
347
  | Op (o, i, d) -> Format.fprintf fmt "%s %i -> %s" o i d
348
  | IncrIntCst n ->  Format.fprintf fmt "incr int cst %i" n
349
  | DecrIntCst n ->  Format.fprintf fmt "decr int cst %i" n
350
  | SwitchIntCst (n, m) ->  Format.fprintf fmt "switch int cst %i -> %i" n m
351

    
352
let fold_mutate_int i = 
353
  if Random.int 100 > threshold_inc_int then
354
    i+1
355
  else if Random.int 100 > threshold_dec_int then
356
    i-1
357
  else if Random.int 100 > threshold_random_int then
358
    Random.int 10
359
  else if Random.int 100 > threshold_switch_int then
360
    try
361
	let idx = Random.int (List.length !int_consts) in
362
        List.nth !int_consts idx
363
    with _ -> i
364
  else
365
    i
366
  
367
let fold_mutate_float f =
368
  if Random.int 100 > threshold_random_float then
369
    Random.float 10.
370
  else 
371
    f
372

    
373
let fold_mutate_op op = 
374
(* match op with *)
375
(* | "+" | "-" | "*" | "/" when Random.int 100 > threshold_arith_op -> *)
376
(*   let filtered = List.filter (fun x -> x <> op) ["+"; "-"; "*"; "/"] in *)
377
(*   List.nth filtered (Random.int 3) *)
378
(* | "&&" | "||" | "xor" | "impl" when Random.int 100 > threshold_bool_op -> *)
379
(*   let filtered = List.filter (fun x -> x <> op) ["&&"; "||"; "xor"; "impl"] in *)
380
(*   List.nth filtered (Random.int 3) *)
381
(* | "<" | "<=" | ">" | ">=" | "!=" | "=" when Random.int 100 > threshold_rel_op -> *)
382
(*   let filtered = List.filter (fun x -> x <> op) ["<"; "<="; ">"; ">="; "!="; "="] in *)
383
(*   List.nth filtered (Random.int 5) *)
384
(* | _ -> op *)
385
  match !target with
386
  | Some (Op(op_orig, 0, op_new)) when op_orig = op -> (
387
    target := None;
388
    op_new
389
  )
390
  | Some (Op(op_orig, n, op_new)) when op_orig = op -> (
391
    target := Some (Op(op_orig, n-1, op_new));
392
    op
393
  )
394
  | _ -> if List.mem op Basic_library.internal_funs then op else rename_app op
395

    
396

    
397
let fold_mutate_var expr = 
398
  (* match (Types.repr expr.expr_type).Types.tdesc with  *)
399
  (* | Types.Tbool -> *)
400
  (*     (\* if Random.int 100 > threshold_negate_bool_var then *\) *)
401
  (*     mkpredef_unary_call Location.dummy_loc "not" expr *)
402
  (*   (\* else  *\) *)
403
  (*   (\*   expr *\) *)
404
  (* | _ -> 
405
 *)expr
406

    
407
let fold_mutate_boolexpr expr =
408
  match !target with
409
  | Some (Boolexpr 0) -> (
410
    target := None;
411
    mkpredef_call expr.expr_loc "not" [expr]
412
  )
413
  | Some (Boolexpr n) ->
414
      (target := Some (Boolexpr (n-1)); expr)
415
  | _ -> expr
416
    
417
let fold_mutate_pre orig_expr e = 
418
  match !target with
419
    Some (Pre 0) -> (
420
      target := None;
421
      Expr_pre ({orig_expr with expr_desc = Expr_pre e}) 
422
    )
423
  | Some (Pre n) -> (
424
    target := Some (Pre (n-1));
425
    Expr_pre e
426
  )
427
  | _ -> Expr_pre e
428
    
429
let fold_mutate_const_value c = 
430
match c with
431
| Const_int i -> (
432
  match !target with
433
  | Some (IncrIntCst 0) -> (target := None; Const_int (i+1))
434
  | Some (DecrIntCst 0) -> (target := None; Const_int (i-1))
435
  | Some (SwitchIntCst (0, id)) -> (target := None; Const_int (List.nth (IntSet.elements (IntSet.remove i !records.consts)) id)) 
436
  | Some (IncrIntCst n) -> (target := Some (IncrIntCst (n-1)); c)
437
  | Some (DecrIntCst n) -> (target := Some (DecrIntCst (n-1)); c)
438
  | Some (SwitchIntCst (n, id)) -> (target := Some (SwitchIntCst (n-1, id)); c)
439
  | _ -> c)
440
| _ -> c
441

    
442
(*
443
  match c with
444
  | Const_int i -> Const_int (fold_mutate_int i)
445
  | Const_real s -> Const_real s (* those are string, let's leave them *)
446
  | Const_float f -> Const_float (fold_mutate_float f)
447
  | Const_array _
448
  | Const_tag _ -> c
449
TODO
450

    
451
				  *)
452
let fold_mutate_const c =
453
  { c with const_value = fold_mutate_const_value c.const_value }
454

    
455
let rec fold_mutate_expr expr =
456
  let new_expr = 
457
    match expr.expr_desc with
458
    | Expr_ident id -> fold_mutate_var expr
459
    | _ -> (
460
      let new_desc = match expr.expr_desc with
461
	| Expr_const c -> Expr_const (fold_mutate_const_value c)
462
	| Expr_tuple l -> Expr_tuple (List.fold_right (fun e res -> (fold_mutate_expr e)::res) l [])
463
	| Expr_ite (i,t,e) -> Expr_ite (fold_mutate_expr i, fold_mutate_expr t, fold_mutate_expr e)
464
	| Expr_arrow (e1, e2) -> Expr_arrow (fold_mutate_expr e1, fold_mutate_expr e2)
465
	| Expr_pre e -> fold_mutate_pre expr (fold_mutate_expr e)
466
	| Expr_appl (op_id, args, r) -> Expr_appl (fold_mutate_op op_id, fold_mutate_expr args, r)
467
  (* Other constructs are kept.
468
  | Expr_fby of expr * expr
469
  | Expr_array of expr list
470
  | Expr_access of expr * Dimension.dim_expr
471
  | Expr_power of expr * Dimension.dim_expr
472
  | Expr_when of expr * ident * label
473
  | Expr_merge of ident * (label * expr) list
474
  | Expr_uclock of expr * int
475
  | Expr_dclock of expr * int
476
  | Expr_phclock of expr * rat *)
477
  | _ -> expr.expr_desc
478
    
479
      in
480
      { expr with expr_desc = new_desc }
481
    )
482
  in
483
  if (Types.repr expr.expr_type).Types.tdesc = Types.Tbool then
484
    fold_mutate_boolexpr new_expr  
485
  else
486
    new_expr
487

    
488
let fold_mutate_eq eq =
489
  { eq with eq_rhs = fold_mutate_expr eq.eq_rhs }
490

    
491
let fold_mutate_stmt stmt =
492
  match stmt with
493
  | Eq eq   -> Eq (fold_mutate_eq eq)
494
  | Aut aut -> assert false
495

    
496
let fold_mutate_node nd = 
497
  { nd with 
498
    node_stmts = 
499
      List.fold_right (fun stmt res -> (fold_mutate_stmt stmt)::res) nd.node_stmts [];
500
    node_id = rename_app nd.node_id
501
  }
502

    
503
let fold_mutate_top_decl td =
504
  match td.top_decl_desc with
505
  | Node nd   -> { td with top_decl_desc = Node  (fold_mutate_node nd)}
506
  | Const cst -> { td with top_decl_desc = Const (fold_mutate_const cst)}
507
  | _ -> td
508
    
509
(* Create a single mutant with the provided random seed *)
510
let fold_mutate_prog prog = 
511
  List.fold_right (fun e res -> (fold_mutate_top_decl e)::res) prog []
512

    
513
let create_mutant prog directive =  
514
  target := Some directive; 
515
  let prog' = fold_mutate_prog prog in
516
  target := None;
517
  prog'
518
  
519

    
520
let op_mutation op = 
521
  let res =
522
    let rem_op l = List.filter (fun e -> e <> op) l in
523
  if List.mem op arith_op then rem_op arith_op else 
524
    if List.mem op bool_op then rem_op bool_op else 
525
      if List.mem op rel_op then rem_op rel_op else 
526
	(Format.eprintf "Failing with op %s@." op;
527
	  assert false
528
	)
529
  in
530
  (* Format.eprintf "Mutation op %s to [%a]@." op (Utils.fprintf_list ~sep:"," Format.pp_print_string) res; *)
531
  res
532

    
533
let rec remains select list =
534
  match list with 
535
    [] -> []
536
  | hd::tl -> if select hd then tl else remains select tl
537
      
538
let next_change m =
539
  let res = 
540
  let rec first_op () = 
541
    try
542
      let min_binding = OpCount.min_binding !records.nb_op in
543
      Op (fst min_binding, 0, List.hd (op_mutation (fst min_binding)))
544
    with Not_found -> first_boolexpr () 
545
  and first_boolexpr () =
546
    if !records.nb_boolexpr > 0 then 
547
      Boolexpr 0 
548
    else first_pre ()
549
  and first_pre () = 
550
    if !records.nb_pre > 0 then 
551
      Pre 0 
552
    else
553
      first_op ()
554
  and first_intcst () =
555
    if IntSet.cardinal !records.consts > 0 then
556
      IncrIntCst 0
557
    else
558
      first_boolexpr ()
559
  in
560
  match m with
561
  | Boolexpr n -> 
562
    if n+1 >= !records.nb_boolexpr then 
563
      first_pre ()
564
    else
565
      Boolexpr (n+1)
566
  | Pre n -> 
567
    if n+1 >= !records.nb_pre then 
568
      first_op ()
569
    else Pre (n+1)
570
  | Op (orig, id, mut_op) -> (
571
    match remains (fun x -> x = mut_op) (op_mutation orig) with
572
    | next_op::_ -> Op (orig, id, next_op)
573
    | [] -> if id+1 >= OpCount.find orig !records.nb_op then (
574
      match remains (fun (k1, _) -> k1 = orig) (OpCount.bindings !records.nb_op) with
575
      | [] -> first_intcst ()
576
      | hd::_ -> Op (fst hd, 0, List.hd (op_mutation (fst hd)))
577
    ) else
578
	Op(orig, id+1, List.hd (op_mutation orig))
579
  )
580
  | IncrIntCst n ->
581
    if n+1 >= IntSet.cardinal !records.consts then
582
      DecrIntCst 0
583
    else IncrIntCst (n+1)
584
  | DecrIntCst n ->
585
    if n+1 >= IntSet.cardinal !records.consts then
586
      SwitchIntCst (0, 0)
587
    else DecrIntCst (n+1)
588
  | SwitchIntCst (n, m) ->
589
    if m+1 > -1 + IntSet.cardinal !records.consts then
590
      SwitchIntCst (n, m+1)
591
    else if n+1 >= IntSet.cardinal !records.consts then
592
      SwitchIntCst (n+1, 0)
593
    else first_boolexpr ()
594

    
595
  in
596
  (* Format.eprintf "from: %a to: %a@." print_directive m print_directive res; *)
597
  res
598

    
599
let fold_mutate nb prog = 
600
  incr random_seed;
601
  Random.init !random_seed;
602
  let find_next_new mutants mutant =
603
    let rec find_next_new init current =
604
      if init = current then raise Not_found else
605
	if List.mem current mutants then
606
	  find_next_new init (next_change current)
607
	else
608
	  current
609
    in
610
    find_next_new mutant (next_change mutant) 
611
  in
612
  (* Creating list of nb elements of mutants *)
613
  let rec create_mutants_directives rnb mutants = 
614
    if rnb <= 0 then mutants 
615
    else 
616
      let random_mutation = 
617
	match Random.int 6 with
618
	| 5 -> IncrIntCst (try Random.int (IntSet.cardinal !records.consts) with _ -> 0)
619
	| 4 -> DecrIntCst (try Random.int (IntSet.cardinal !records.consts) with _ -> 0)
620
	| 3 -> SwitchIntCst ((try Random.int (IntSet.cardinal !records.consts) with _ -> 0), (try Random.int (-1 + IntSet.cardinal !records.consts) with _ -> 0))
621
	| 2 -> Pre (try Random.int !records.nb_pre with _ -> 0)
622
	| 1 -> Boolexpr (try Random.int !records.nb_boolexpr with _ -> 0)
623
	| 0 -> let bindings = OpCount.bindings !records.nb_op in
624
	       let op, nb_op = List.nth bindings (try Random.int (List.length bindings) with _ -> 0) in
625
	       let new_op = List.nth (op_mutation op) (try Random.int (List.length (op_mutation op)) with _ -> 0) in
626
	       Op (op, (try Random.int nb_op with _ -> 0), new_op)
627
	| _ -> assert false
628
      in
629
      if List.mem random_mutation mutants then
630
	try
631
	  let new_mutant = (find_next_new mutants random_mutation) in
632
	  report ~level:2 (fun fmt -> fprintf fmt " %i mutants generated out of %i expected@." (nb-rnb) nb);
633
	 create_mutants_directives (rnb-1) (new_mutant::mutants) 
634
	with Not_found -> (
635
	  report ~level:1 (fun fmt -> fprintf fmt "Only %i mutants generated out of %i expected@." (nb-rnb) nb); 
636
	  mutants
637
	)
638
      else
639
	create_mutants_directives (rnb-1) (random_mutation::mutants)
640
  in
641
  let mutants_directives = create_mutants_directives nb [] in
642
  List.map (fun d -> d, create_mutant prog d) mutants_directives 
643
  
644

    
645
let mutate nb prog =
646
  records := compute_records prog;
647
  (* Format.printf "Records: %i pre, %i boolexpr" (\* , %a ops *\) *)
648
  (*   !records.nb_pre *)
649
(*     !records.nb_boolexpr *)
650
(*     (\* !records.op *\) *)
651
(* ;  *)   
652
  fold_mutate nb prog, print_directive
653

    
654

    
655

    
656

    
657
(* Local Variables: *)
658
(* compile-command:"make -C .." *)
659
(* End: *)
660

    
661