package frama-c

  1. Overview
  2. Docs
package frama-c
Legend:
Page
Library
Module
Module type
Parameter
Class
Class type
Source

Source file memory.ml

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
(**************************************************************************)
(*                                                                        *)
(*  This file is part of Frama-C.                                         *)
(*                                                                        *)
(*  Copyright (C) 2007-2024                                               *)
(*    CEA (Commissariat à l'énergie atomique et aux énergies              *)
(*         alternatives)                                                  *)
(*                                                                        *)
(*  you can redistribute it and/or modify it under the terms of the GNU   *)
(*  Lesser General Public License as published by the Free Software       *)
(*  Foundation, version 2.1.                                              *)
(*                                                                        *)
(*  It is distributed in the hope that it will be useful,                 *)
(*  but WITHOUT ANY WARRANTY; without even the implied warranty of        *)
(*  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *)
(*  GNU Lesser General Public License for more details.                   *)
(*                                                                        *)
(*  See the GNU Lesser General Public License version 2.1                 *)
(*  for more details (enclosed in the file licenses/LGPLv2.1).            *)
(*                                                                        *)
(**************************************************************************)

open Cil_types
open Cil_datatype
module Ufind = UnionFind.Make(Store)
module Vmap = Varinfo.Map
module Vset = Varinfo.Set
module Lmap = Map.Make(String)
module Lset = Set.Make(String)

(* -------------------------------------------------------------------------- *)
(* --- Region Maps                                                        --- *)
(* -------------------------------------------------------------------------- *)

(* All offsets in bits *)

type node = chunk Ufind.rref

and layout =
  | Blob
  | Cell of int * node option
  | Compound of int * Fields.domain * node Ranges.t

and chunk = {
  cparents: node list ;
  cpointed: node list ;
  croots: Vset.t ;
  clabels: Lset.t ;
  creads: Access.Set.t ;
  cwrites: Access.Set.t ;
  cshifts: Access.Set.t ;
  clayout: layout ;
}

type rg = node Ranges.range

type map = {
  store: chunk Ufind.store ;
  mutable locked: bool ;
  mutable roots: node Vmap.t ;
  mutable labels: node Lmap.t ;
}

(* -------------------------------------------------------------------------- *)
(* --- Accessors                                                          --- *)
(* -------------------------------------------------------------------------- *)

let sizeof = function Blob -> 0 | Cell(s,_) | Compound(s,_,_) -> s
let ranges = function Blob | Cell _ -> [] | Compound(_,_,R rs) -> rs
let fields = function Blob | Cell _ -> Fields.empty | Compound(_,fds,_) -> fds
let pointed = function Blob | Compound _ -> None | Cell(_,p) -> p

let types (m : chunk) : typ list =
  let pool = ref Typ.Set.empty in
  let add acs =
    pool := Typ.Set.add (Cil.unrollType @@ Access.typeof acs) !pool in
  Access.Set.iter add m.creads ;
  Access.Set.iter add m.cwrites ;
  Typ.Set.elements !pool

let failwith_locked m fn =
  if m.locked then raise (Invalid_argument fn)

let lock m = m.locked <- true
let unlock m = m.locked <- false

(* -------------------------------------------------------------------------- *)
(* --- Printers                                                           --- *)
(* -------------------------------------------------------------------------- *)

let pp_node fmt (n : node) = Format.fprintf fmt "R%04x" @@ Store.id n

let pp_field fields fmt fd =
  if Options.debug_atleast 1 then Ranges.pp_range fmt fd else
    Fields.pretty fields fmt fd

let pp_layout fmt = function
  | Blob -> Format.pp_print_string fmt "<blob>"
  | Cell(s,None) -> Format.fprintf fmt "<%04d>" s
  | Cell(s,Some n) -> Format.fprintf fmt "<%04d>(*%a)" s pp_node n
  | Compound(s,fields,rg) ->
    Format.fprintf fmt "@[<hv 0>{%04d" s ;
    Ranges.iteri
      (fun (rg : rg) ->
         Format.fprintf fmt "@ | %a: %a" (pp_field fields) rg pp_node rg.data
      ) rg ;
    Format.fprintf fmt "@ }@]"

let pp_chunk fmt (n: node) (m: chunk) =
  begin
    let acs r s = if Access.Set.is_empty s then '-' else r in
    Format.fprintf fmt "@[<hov 2>%a: %c%c%c" pp_node n
      (acs 'R' m.creads) (acs 'W' m.cwrites) (acs 'A' m.cshifts) ;
    List.iter (Format.fprintf fmt "@ (%a)" Typ.pretty) (types m) ;
    Lset.iter (Format.fprintf fmt "@ %s:") m.clabels ;
    Vset.iter (Format.fprintf fmt "@ %a" Varinfo.pretty) m.croots ;
    if Options.debug_atleast 1 then
      begin
        Access.Set.iter (Format.fprintf fmt "@ R:%a" Access.pretty) m.creads ;
        Access.Set.iter (Format.fprintf fmt "@ W:%a" Access.pretty) m.cwrites ;
        Access.Set.iter (Format.fprintf fmt "@ A:%a" Access.pretty) m.cshifts ;
      end ;
    Format.fprintf fmt "@ %a ;@]" pp_layout m.clayout ;
  end
[@@ warning "-32"]

(* -------------------------------------------------------------------------- *)
(* --- Map Constructors                                                   --- *)
(* -------------------------------------------------------------------------- *)

let create () = {
  locked = false ;
  store = Ufind.new_store () ;
  roots = Vmap.empty ;
  labels = Lmap.empty ;
}

let copy ?locked m = {
  locked = (match locked with None -> m.locked | Some l -> l) ;
  store = Ufind.copy m.store ;
  roots = m.roots ;
  labels = m.labels ;
}

let empty = {
  cparents = [] ;
  cpointed = [] ;
  croots = Vset.empty ;
  clabels = Lset.empty ;
  creads = Access.Set.empty ;
  cwrites = Access.Set.empty ;
  cshifts = Access.Set.empty ;
  clayout = Blob ;
}

(* -------------------------------------------------------------------------- *)
(* --- Map                                                                --- *)
(* -------------------------------------------------------------------------- *)

let id = Store.id
let forge = Store.forge
let equal (m: map) = Ufind.eq m.store

let node map node =
  try Ufind.find map.store node
  with Not_found -> node

let nodes map ns = Store.list @@ List.map (node map) ns

let get map node =
  try Ufind.get map.store node
  with Not_found -> empty

let update (m: map) (n: node) (f: chunk -> chunk) =
  let r = get m n in
  Ufind.set m.store n (f r)

(* -------------------------------------------------------------------------- *)
(* --- Chunk Constructors                                                 --- *)
(* -------------------------------------------------------------------------- *)

let new_chunk (m: map) ?(size=0) ?ptr ?pointed () =
  failwith_locked m "Region.Memory.new_chunk" ;
  let clayout =
    match ptr with
    | None -> if size = 0 then Blob else Cell(size,None)
    | Some _ -> Cell(Ranges.gcd size (Cil.bitsSizeOf Cil_const.voidPtrType), ptr)
  in
  let cpointed =
    match pointed with
    | None -> []
    | Some ptr -> [ptr]
  in
  Ufind.make m.store { empty with clayout ; cpointed }

let new_range (m: map) ?(fields=Fields.empty) ~size ~offset ~length data : node =
  failwith_locked m "Region.Memory.new_range" ;
  let last = offset + length in
  if not (0 <= offset && offset < last && last <= size) then
    raise (Invalid_argument "Region.Memory.add_range") ;
  let ranges = Ranges.singleton { offset ; length ; data } in
  let clayout = Compound(size, fields, ranges) in
  let n = Ufind.make m.store { empty with clayout } in
  update m data (fun r -> { r with cparents = nodes m @@ n :: r.cparents }) ; n

let add_root (m: map) v =
  try Vmap.find v m.roots with Not_found ->
    failwith_locked m "Region.Memory.add_root" ;
    let n = new_chunk m () in
    update m n (fun d -> { d with croots = Vset.singleton v }) ;
    m.roots <- Vmap.add v n m.roots ; n

let add_label (m: map) a =
  try Lmap.find a m.labels with Not_found ->
    failwith_locked m "Region.Memory.add_label" ;
    let n = new_chunk m () in
    update m n (fun d -> { d with clabels = Lset.singleton a }) ;
    m.labels <- Lmap.add a n m.labels ; n

(* -------------------------------------------------------------------------- *)
(* --- Iterator                                                           --- *)
(* -------------------------------------------------------------------------- *)

type range = {
  label: string ; (* pretty printed fields *)
  offset: int ;
  length: int ;
  cells: int ;
  data: node ;
}

type region = {
  node: node ;
  parents: node list ;
  roots: varinfo list ;
  labels: string list ;
  types: typ list ;
  fields: Fields.domain ;
  reads: Access.acs list ;
  writes: Access.acs list ;
  shifts: Access.acs list ;
  sizeof: int ;
  ranges: range list ;
  pointed: node option ;
}

let pp_cells fmt = function
  | 1 -> ()
  | 0 -> Format.fprintf fmt "[…]"
  | n -> Format.fprintf fmt "[%d]" n

type slice =
  | Padding of int
  | Range of range

let pad p q s =
  let n = q - p in
  if n > 0 then Padding n :: s else s

let rec span k s = function
  | [] -> pad k s []
  | r::rs -> pad k r.offset @@ Range r :: span (r.offset + r.length) s rs

let pp_slice fields fmt = function
  | Padding n ->
    Format.fprintf fmt "@ %a;" Fields.pp_bits n
  | Range r ->
    Format.fprintf fmt "@ %t: %a%a;"
      (Fields.pslice ~fields ~offset:r.offset ~length:r.length)
      pp_node r.data
      pp_cells r.cells

let pp_range fmt (r: range) =
  Format.fprintf fmt "@ %d..%d: %a%a;"
    r.offset (r.offset + r.length) pp_node r.data pp_cells r.cells

let pp_region fmt (m: region) =
  begin
    let acs r s = if s = [] then '-' else r in
    Format.fprintf fmt "@[<hov 2>%a: %c%c%c"
      pp_node m.node
      (acs 'R' m.reads) (acs 'W' m.writes) (acs 'A' m.shifts) ;
    List.iter (Format.fprintf fmt "@ %s:") m.labels ;
    List.iter (Format.fprintf fmt "@ %a" Varinfo.pretty) m.roots ;
    List.iter (Format.fprintf fmt "@ (%a)" Typ.pretty) m.types ;
    Format.fprintf fmt "@ %db" m.sizeof ;
    Option.iter (Format.fprintf fmt "@ (*%a)" pp_node) m.pointed ;
    if m.ranges <> [] then
      begin
        Format.fprintf fmt "@ @[<hv 0>@[<hv 2>{" ;
        if Options.debug_atleast 1 then
          List.iter (pp_range fmt) m.ranges
        else
          List.iter (pp_slice m.fields fmt) (span 0 m.sizeof m.ranges) ;
        Format.fprintf fmt "@]@ }@]" ;
      end ;
    if Options.debug_atleast 1 then
      begin
        List.iter (Format.fprintf fmt "@ R:%a" Access.pretty) m.reads ;
        List.iter (Format.fprintf fmt "@ W:%a" Access.pretty) m.writes ;
        List.iter (Format.fprintf fmt "@ A:%a" Access.pretty) m.shifts ;
      end ;
    Format.fprintf fmt " ;@]" ;
  end

let make_range (m: map) fields Ranges.{ length ; offset ; data } : range =
  let s = sizeof (get m data).clayout in
  let p = Fields.pslice ~fields ~offset ~length in
  {
    label = Format.asprintf "%t" p ;
    offset ; length ;
    cells = if s = 0 then 0 else length / s ;
    data = node m data ;
  }

let make_region (m: map) (n: node) (r: chunk) : region =
  let fields = fields r.clayout in
  {
    node = n ;
    parents = nodes m r.cparents ;
    roots = Vset.elements r.croots ;
    labels = Lset.elements r.clabels ;
    reads = Access.Set.elements r.creads ;
    writes = Access.Set.elements r.cwrites ;
    shifts = Access.Set.elements r.cshifts ;
    types = types r ;
    sizeof = sizeof r.clayout ;
    fields ; ranges = List.map (make_range m fields) @@ ranges r.clayout ;
    pointed = Option.map (node m) (pointed r.clayout) ;
  }

let region map n = make_region map n (get map n)

let rec walk h m f n =
  let n = Ufind.find m.store n in
  let id = Store.id n in
  try Hashtbl.find h id with Not_found ->
    Hashtbl.add h id () ;
    let r = Ufind.get m.store n in
    f (make_region m n r) ;
    match r.clayout with
    | Blob -> ()
    | Cell(_,p) -> Option.iter (walk h m f) p
    | Compound(_,_,rg) -> Ranges.iter (walk h m f) rg

let iter (m:map) (f: region -> unit) =
  let h = Hashtbl.create 0 in
  Vmap.iter (fun _x n -> walk h m f n) m.roots

let rec walk_node h m (f: node -> unit) n =
  let n = Ufind.find m.store n in
  let id = Store.id n in
  try Hashtbl.find h id with Not_found ->
    Hashtbl.add h id () ;
    f n ;
    let r = Ufind.get m.store n in
    match r.clayout with
    | Blob -> ()
    | Cell(_,p) -> Option.iter (walk_node h m f) p
    | Compound(_,_,rg) -> Ranges.iter (walk_node h m f) rg

let iter_node (m:map) (f: node -> unit) =
  let h = Hashtbl.create 0 in
  Vmap.iter (fun _x n -> walk_node h m f n) m.roots

let regions map =
  let pool = ref [] in
  iter map (fun r -> pool := r :: !pool) ;
  List.rev !pool


let parents (m: map) (r: node) =
  let chunk = Ufind.get m.store r in
  nodes m chunk.cparents

let roots (m: map) (r: node) =
  let chunk = Ufind.get m.store r in Vset.elements chunk.croots

(* -------------------------------------------------------------------------- *)
(* --- Merge                                                              --- *)
(* -------------------------------------------------------------------------- *)

type queue = (node * node) Queue.t

let singleton ~size = function
  | None -> Ranges.empty
  | Some r -> Ranges.range ~length:size r

let merge_node (m: map) (q: queue) (a: node) (b: node) : node =
  if not @@ Ufind.eq m.store a b then Queue.push (a,b) q ;
  Ufind.find m.store (min a b)

let merge_opt (m: map) (q: queue)
    (pa : node option) (pb : node option) : node option =
  match pa, pb with
  | None, p | p, None -> p
  | Some pa, Some pb -> Some (merge_node m q pa pb)

let merge_range (m: map) (q: queue) (ra : rg) (rb : rg) : node =
  let na = ra.data in
  let nb = rb.data in
  let ma = ra.offset + ra.length in
  let mb = rb.offset + rb.length in
  let dp = ra.offset - rb.offset in
  let dq = ma - mb in
  let sa = sizeof (get m na).clayout in
  let sb = sizeof (get m nb).clayout in
  let size = Ranges.(sa %. sb %. dp %. dq) in
  let data = merge_node m q na nb in
  if size = sa && size = sb then data else
    merge_node m q (new_chunk m ~size ()) data

let merge_ranges (m: map) (q: queue)
    (sa : int) (fa : Fields.domain) (wa : node Ranges.t)
    (sb : int) (fb : Fields.domain) (wb : node Ranges.t)
  : layout =
  let fields = Fields.union fa fb in
  if sa = sb then
    Compound(sa, fields, Ranges.merge (merge_range m q) wa wb)
  else
    let size = Ranges.gcd sa sb in
    let ra = Ranges.squash (merge_node m q) wa in
    let rb = Ranges.squash (merge_node m q) wb in
    Compound(size, fields, singleton ~size @@ merge_opt m q ra rb)

let merge_layout (m: map) (q: queue) (a : layout) (b : layout) : layout =
  match a, b with
  | Blob, c | c, Blob -> c

  | Cell(sa,pa) , Cell(sb,pb) -> Cell(Ranges.gcd sa sb, merge_opt m q pa pb)

  | Compound(sa,fa,wa), Compound(sb,fb,wb) ->
    merge_ranges m q sa fa wa sb fb wb

  | Compound(sr,fr,wr), Cell(sx,None)
  | Cell(sx,None), Compound(sr,fr,wr) ->
    let size = Ranges.gcd sx sr in
    Compound(size, fr, singleton ~size @@ Ranges.squash (merge_node m q) wr)

  | Compound(sr,fr,wr), Cell(sx,Some ptr)
  | Cell(sx,Some ptr), Compound(sr,fr,wr) ->
    let rp = new_chunk m ~size:sx ~ptr () in
    let fx = Fields.empty in
    let wx = Ranges.range ~length:sx rp in
    merge_ranges m q sx fx wx sr fr wr

let merge_region (m: map) (q: queue) (a : chunk) (b : chunk) : chunk = {
  cparents = nodes m @@ Store.bag a.cparents b.cparents ;
  cpointed = nodes m @@ Store.bag a.cpointed b.cpointed ;
  clabels = Lset.union a.clabels b.clabels ;
  croots = Vset.union a.croots b.croots ;
  creads = Access.Set.union a.creads b.creads ;
  cwrites = Access.Set.union a.cwrites b.cwrites ;
  cshifts = Access.Set.union a.cshifts b.cshifts ;
  clayout = merge_layout m q a.clayout b.clayout ;
}

let do_merge (m: map) (q: queue) (a: node) (b: node): unit =
  begin
    let ra = Ufind.get m.store a in
    let rb = Ufind.get m.store b in
    let rx = Ufind.union m.store a b in
    let rc = merge_region m q ra rb in
    Ufind.set m.store rx rc ;
  end

let merge_all (m:map) = function
  | [] -> ()
  | r::rs ->
    let q = Queue.create () in
    List.iter (fun r' -> ignore @@ merge_node m q r r') rs ;
    while not @@ Queue.is_empty q do
      let a,b = Queue.pop q in
      do_merge m q a b ;
    done

let merge (m: map) (a: node) (b: node) : unit =
  failwith_locked m "Region.Memory.merge" ;
  merge_all m [a;b]

let merge_copy (m: map) ~(l: node) ~(r: node) : unit =
  let { clayout } = get m r in
  merge_all m [ l; Ufind.make m.store { empty with clayout } ]

(* -------------------------------------------------------------------------- *)
(* --- Offset                                                             --- *)
(* -------------------------------------------------------------------------- *)

let add_field (m:map) (r:node) (fd:fieldinfo) : node =
  let ci = fd.fcomp in
  if ci.cstruct then
    let size = Cil.bitsSizeOf (TComp(ci,[])) in
    let offset, length = Cil.fieldBitsOffset fd in
    let rf = new_chunk m () in
    let fields = Fields.singleton fd in
    let rc = new_range m ~fields ~size ~offset ~length rf in
    ignore @@ merge m r rc ; rf
  else r

let add_index (m:map) (r:node) (ty:typ) (n:int) : node =
  let s = Cil.bitsSizeOf ty * n in
  let re = new_chunk m () in
  let rc = new_range m ~size:s ~offset:0 ~length:s re in
  ignore @@ merge m r rc ; re

let add_points_to (m: map) (a: node) (b : node) =
  begin
    failwith_locked m "Region.Memory.points_to" ;
    ignore @@ merge m a @@ new_chunk m ~ptr:b () ;
    ignore @@ merge m b @@ new_chunk m ~pointed:a () ;
  end

let add_value (m:map) (rv:node) (ty:typ) : node option =
  if Cil.isPointerType ty then
    begin
      failwith_locked m "Region.Memory.add_value" ;
      let rp = new_chunk m ~pointed:rv () in
      ignore @@ merge m rv @@ new_chunk m ~ptr:rp () ;
      Some rp
    end
  else
    None

(* -------------------------------------------------------------------------- *)
(* --- Access                                                             --- *)
(* -------------------------------------------------------------------------- *)

let sized (m:map) (a:node) (ty: typ) =
  let sr = sizeof (get m a).clayout in
  let size = Ranges.gcd sr (Cil.bitsSizeOf ty) in
  if sr <> size then ignore (merge m a (new_chunk m ~size ()))

let read (m: map) (a: node) from =
  failwith_locked m "Region.Memory.read" ;
  let r = get m a in
  Ufind.set m.store a { r with creads = Access.Set.add from r.creads } ;
  sized m a (Access.typeof from)

let write (m: map) (a: node) from =
  failwith_locked m "Region.Memory.write" ;
  let r = get m a in
  Ufind.set m.store a { r with cwrites = Access.Set.add from r.cwrites } ;
  sized m a (Access.typeof from)

let shift (m: map) (a: node) from =
  failwith_locked m "Region.Memory.shift" ;
  let r = get m a in
  Ufind.set m.store a { r with cshifts = Access.Set.add from r.cshifts } ;
  sized m a (Access.typeof from)

(* -------------------------------------------------------------------------- *)
(* --- Lookup                                                            ---- *)
(* -------------------------------------------------------------------------- *)

let points_to m (r : node) : node option =
  let rg = Ufind.get m.store r in
  match rg.clayout with
  | Blob | Compound _ | Cell(_,None) -> None
  | Cell(_,Some r) -> Some (Ufind.find m.store r)

let pointed_by m (r : node) =
  let rg = Ufind.get m.store r in rg.cpointed

let cvar (m: map) (v: varinfo) : node =
  Ufind.find m.store @@ Vmap.find v m.roots

let rec move (m: map) (r: node) (p: int) (s: int) =
  let c = Ufind.get m.store r in
  match c.clayout with
  | Blob | Cell _ -> r
  | Compound(s0,_,rgs) ->
    if s0 <= s then r else
      let rg = Ranges.find p rgs in
      move m rg.data (p - rg.offset) s

let field (m: map) (r: node) (fd: fieldinfo) : node =
  let s = Cil.bitsSizeOf fd.ftype in
  let (p,_) = Cil.fieldBitsOffset fd in
  move m r p s

let index (m : map) (r: node) (ty:typ) : node =
  move m r 0 (Cil.bitsSizeOf ty)

let rec lval (m: map) (h,ofs) : node =
  offset m (lhost m h) (Cil.typeOfLhost h) ofs

and lhost (m: map) (h: lhost) : node =
  match h with
  | Var x -> cvar m x
  | Mem e ->
    match exp m e with
    | Some r -> r
    | None -> raise Not_found

and offset (m: map) (r: node) (ty: typ) (ofs: offset) : node =
  match ofs with
  | NoOffset -> Ufind.find m.store r
  | Field (fd, ofs) ->
    offset m (field m r fd) fd.ftype ofs
  | Index (_, ofs) ->
    let te = Cil.typeOf_array_elem ty in
    offset m (index m r te) te ofs

and exp (m: map) (e: exp) : node option =
  match e.enode with
  | Const _
  | SizeOf _ | SizeOfE _ | SizeOfStr _ | AlignOf _ | AlignOfE _ -> None
  | Lval lv -> points_to m @@ lval m lv
  | AddrOf lv | StartOf lv -> Some (lval m lv)
  | CastE(_, e) -> exp m e
  | BinOp((PlusPI|MinusPI),p,_,_) -> exp m p
  | UnOp (_, _, _) | BinOp (_, _, _, _) -> None

(* -------------------------------------------------------------------------- *)

let included map source target : bool =
  let exception Reached in
  try
    let q = Queue.create () in (* only marked nodes *)
    let push r =
      let r = node map r in
      if equal map target r then raise Reached else Queue.push r q
    in
    push source ;
    let visited = Hashtbl.create 0 in
    while true do
      let node = Queue.pop q in
      if equal map target node then raise Exit else
        let id = id node in
        if not @@ Hashtbl.mem visited id then
          begin
            Hashtbl.add visited id () ;
            List.iter push (parents map node) ;
          end
    done ;
    assert false
  with
  | Queue.Empty -> false
  | Reached -> true

let separated map r1 r2 =
  not (included map r1 r2) && not (included map r2 r1)

(* -------------------------------------------------------------------------- *)

let reads (m : map) (r:node) =
  let node = Ufind.get m.store r in
  List.map Access.typeof @@ Access.Set.elements node.creads

let writes (m : map) (r:node) =
  let node = Ufind.get m.store r in
  List.map Access.typeof @@ Access.Set.elements node.cwrites

let shifts (m : map) (r:node) =
  let node = Ufind.get m.store r in
  List.map Access.typeof @@ Access.Set.elements node.cshifts
OCaml

Innovation. Community. Security.

GitHub Discord Twitter Peertube RSS
About
Changelog Releases Industrial Users Academic Users Why OCaml
Ecosystem
Packages Community Events OCaml Planet Jobs
Resources
Install OCaml Get Started Platform Tools Language Manual Standard Library API Books Exercises Papers OCaml Playground Logo
Policies
Carbon Footprint Governance Privacy Code of Conduct