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fccc685 Initial open-source release
MLstate authored
1 (*
2 Copyright © 2011 MLstate
3
4 This file is part of OPA.
5
6 OPA is free software: you can redistribute it and/or modify it under the
7 terms of the GNU Affero General Public License, version 3, as published by
8 the Free Software Foundation.
9
10 OPA is distributed in the hope that it will be useful, but WITHOUT ANY
11 WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
12 FOR A PARTICULAR PURPOSE. See the GNU Affero General Public License for
13 more details.
14
15 You should have received a copy of the GNU Affero General Public License
16 along with OPA. If not, see <http://www.gnu.org/licenses/>.
17 *)
18 (**
19 Opa and Qml compilers are based on this mechanism.
20 We use this file as a tutorial and a memo because in qml and opa, the proportion
21 of the asts may lead to be confusing about keeping in mind this global design.
22
23 This file is a also a tiny example of how to use the passlib pass handler and track system.
24
25 @author Mathieu Barbin
26 @author Quentin Bourgerie
27 @author Valentin Gatien-Baron
28 *)
29
30 (* you can search for 'open' in that file *)
31
32 module Arg = Base.Arg
33 module List = Base.List
34 module String = Base.String
35
36 module LangAst =
37 struct
38 type expr =
39 | A
40 | B of expr * expr
41 | K of int
42 | Directive of (PassTracker.t * expr)
43
44 type code_elt =
45 | Val of string * expr
46 | Package of [`declaration | `import] * string * FilePos.pos
47
48 type code = code_elt list
49 end
50
51 module LangWalk =
52 struct
53 module L = LangAst
54 module Subs =
55 struct
56 type 'a t = LangAst.expr constraint 'a = _ * _ * _
57 let foldmap tra acc t =
58 match t with
59 | L.A -> acc, t
60 | L.B (a, b) ->
61 let acc, a' = tra acc a in
62 let acc, b' = tra acc b in
63 acc,
64 if a == a' && b == b' then t else
65 L.B (a', b')
66 | L.K _ -> acc, t
67 | L.Directive (k, e) ->
68 let acc, e' = tra acc e in
69 acc,
70 if e == e' then t else
71 L.Directive (k, e')
72 let iter x = Traverse.Unoptimized.iter foldmap x
73 let map x = Traverse.Unoptimized.map foldmap x
74 let fold x = Traverse.Unoptimized.fold foldmap x
75 end
76 module Expr = Traverse.Make2 ( Subs )
77 module Elt_Subs =
78 struct
79 type 'a t = LangAst.expr constraint 'a = _ * _ * _
80 type 'a container = LangAst.code_elt constraint 'a = _ * _ * _
81 let foldmap tra acc t = match t with
82 | L.Val (s, e) ->
83 let acc, e' = tra acc e in
84 acc,
85 if e == e' then t else
86 L.Val (s, e')
87 | L.Package _ -> acc, t
88 let iter tra = function
89 | L.Val (_, e) -> tra e
90 | L.Package _ -> ()
91 let map x = Traverse.Unoptimized.map foldmap x
92 let fold x = Traverse.Unoptimized.fold foldmap x
93 end
94 module Elt = Traverse.MakeLift1 (Elt_Subs) (Expr)
95 module Code_Subs =
96 struct
97 type 'a t = LangAst.code_elt constraint 'a = _ * _ * _
98 type 'a container = LangAst.code constraint 'a = _ * _ * _
99 let iter = List.iter
100 let map = List.map
101 let fold = List.fold_left
102 let foldmap = List.fold_left_map
103 end
104 module Code = Traverse.MakeLift2 (Code_Subs) (Elt)
105 (* bring freds work there : ast projector *)
106 (* usefull for meta opa (bsl ast projector) *)
107 type 'proj projector =
108 {
109 a : 'proj ;
110 b : 'proj -> 'proj -> 'proj ;
111 k : int -> 'proj ;
112 directive : PassTracker.t -> 'proj -> 'proj ;
113 }
114 let projection proj =
115 let rec aux = function
116 | L.A -> proj.a
117 | L.B (a, b) -> proj.b (aux a) (aux b)
118 | L.K i -> proj.k i
119 | L.Directive (t, e) -> proj.directive t (aux e)
120 in aux
121 (* even more generical than the traverse *)
122 (* if we define a foldmap_projection, you'll get
123 the walker foldmap by applying it with LangCons
124 as argument *)
125 end
126
127 module LangCons =
128 struct
129 module L = LangAst
130 let a = L.A
131 let b a b = L.B (a, b)
132 let k i = L.K i
133 end
134
135 module LangPrint =
136 struct
137 module L = LangAst
138 class print =
139 object(self)
140 method expr fmt = function
141 | L.A -> Format.pp_print_char fmt 'A'
142 | L.B (a, b) -> Format.fprintf fmt "@[<v2>B@ (%a)@ (%a)@]" self#expr a self#expr b
143 | L.K i -> Format.pp_print_int fmt i
144 | L.Directive (_, e) -> self#expr fmt e
145 method code_elt fmt = function
146 | L.Val (s, expr') -> Format.fprintf fmt "@[<2>val %s =@\n%a@]" s self#expr expr'
147 | L.Package (`declaration, name, _) -> Format.fprintf fmt "package %s" name
148 | L.Package (`import, name, _) -> Format.fprintf fmt "import %s" name
149 method code fmt =
150 List.iter (fun elt -> Format.fprintf fmt "%a@\n@\n" self#code_elt elt)
151 end
152 class bb_printer =
153 object(self)
154 inherit print as super
155 method expr fmt = function
156 | L.B (a, b) -> Format.fprintf fmt "@[<v2>BB@ (%a)@ (%a)@]" self#expr a self#expr b
157 | e -> super#expr fmt e
158 end
159 let p = new print
160 let expr = p#expr
161 let code_elt = p#code_elt
162 let code = p#code
163 end
164
165 module LangUtils =
166 struct
167 module B =
168 struct
169 type 'a b_util = LangAst.expr -> LangAst.expr -> 'a
170 end
171 end
172
173 module LangTrack =
174 struct
175 module L = LangAst
176
177 let trackers iter =
178 LangWalk.Code.iter
179 (function
180 | L.Directive (t, e) -> iter.PassTracker.track (PassTracker.filename t) LangPrint.expr e
181 | _ -> () )
182
183 let vals iter = List.iter (
184 function
185 | ( L.Val (s, _) ) as v -> iter.PassTracker.track s LangPrint.code_elt v
186 | _ -> ()
187 )
188
189 let code_id = PassHandler.define_printer "code"
190
191 let printers = [
192 code_id, LangPrint.code ;
193 ]
194
195 let trackers_id = PassHandler.define_tracker "trackers"
196 let val_id = PassHandler.define_tracker "val"
197
198 let trackers = [
199 trackers_id, trackers ;
200 val_id, vals ;
201 ]
202 end
203
204 module LangError :
205 sig
206 type context = (* or abstract *)
207 {
208 code_elt : LangAst.code_elt ;
209 expr : LangAst.expr ;
210 }
211 val context : LangAst.code_elt -> LangAst.expr -> context
212 val check_fail : PassHandler.cond_id -> context -> ('a, 'error) OManager.oformat -> 'a
213 val scheck_fail : PassHandler.cond_id -> context -> ('a, unit) OManager.oformat -> 'a
214
215 (** Overlaying PassHandler for located internal errors *)
216 val cond_violation : PassHandler.cond_id -> context -> ('a, 'error) OManager.oformat -> 'a
217 val scond_violation : PassHandler.cond_id -> context -> ('a, unit) OManager.oformat -> 'a
218 val i_error : PassHandler.cond_id option -> context -> ('a, 'error) OManager.oformat -> 'a
219 val i_serror : PassHandler.cond_id option -> context -> ('a, unit) OManager.oformat -> 'a
220
221 (** Overlaying OManager for located errors *)
222 (* val error : context -> ('a, unit, string, unit) format4 -> 'a *)
223 (* val serror : context -> ('a, unit, string, unit) format4 -> 'a *)
224 (* val warning : wclass:WarningClass.wclass -> context -> ('a, unit, string, unit) format4 -> 'a *)
225 (* etc with the interface of OManager by partial call of the type (using internally OManager) *)
226 end =
227 struct
228 type context =
229 {
230 code_elt : LangAst.code_elt ;
231 expr : LangAst.expr ;
232 }
233 let context code_elt expr = { code_elt = code_elt ; expr = expr }
234 let context_printer fmt context =
235 Format.fprintf fmt "In the following toplevel definition :@\n%a@\nIn the following expression@\n%a\n" LangPrint.code_elt context.code_elt LangPrint.expr context.expr
236 let console fmt context = Format.fprintf fmt "%a@\n" LangPrint.expr context.expr
237 let check_fail c =
238 PassHandler.check_fail ~full:context_printer ~console c
239
240 let scheck_fail c =
241 PassHandler.scheck_fail ~full:context_printer ~console c
242
243 (* overlaying for passes *)
244 let scond_violation c = PassHandler.scond_violation context_printer c
245 let cond_violation c = PassHandler.cond_violation context_printer c
246 let i_error c = PassHandler.i_error context_printer c
247 let i_serror c = PassHandler.i_serror context_printer c
248 end
249
250 (* introduce some buggy scenario in the compiler (see documentation in arg.parse) *)
251 let bug_rewriting = ref false
252 let bug_allowed_cond_violation = ref false
253 let bug_cond_violation_contradiction = ref false
254 let bug_unbound_cond_violation = ref false
255 let bug_not_found = ref false
256
257 let current_filename = ref ""
258 let current_content = ref ""
259 let current_package_index = ref 1
260
261 let extrapaths = ref []
262
263 module LangCheck =
264 struct
265 type ('env, 'a) checker = ('env -> 'a) -> 'env PassHandler.cond
266 module K_values :
267 sig
268 val positives : ('env, LangAst.code) checker
269 val positives_id : PassHandler.cond_id
270 end =
271 struct
272 module L = LangAst
273
274 let (!!) code_elt expr = LangError.context code_elt expr
275
276 let positives_id = PassHandler.define_cond (* WarningClass.cond_theme_example
277 but there for testing : *) WarningClass.cond
278 (* all K are positives *)
279 let positives extract =
280 PassHandler.make_condition positives_id
281 (fun env -> List.iter
282 (function
283 | ( L.Val (_, e) ) as v ->
284 LangWalk.Expr.iter
285 (fun e -> match e with
286 | ( L.K i ) as e -> if !bug_cond_violation_contradiction then () else
287 if i < 0 then LangError.scheck_fail positives_id (!! v e) "positives check: %d < 0\n" i
288 | _ -> ()
289 ) e
290 | _ -> ()
291 )
292 (extract env)
293 )
294 end
295
296 module OtherTheme =
297 struct
298 end
299 end
300
301 module Lang =
302 struct
303 module Ast = LangAst
304 module Walk = LangWalk
305 module Cons = LangCons
306 (* module DeCons = LangDecons *)
307 module Print = LangPrint
308 (* module Parse = LangParse *)
309 module Utils = LangUtils
310 module Track = LangTrack
311 module Error = LangError
312 module Check = LangCheck
313 end
314
315 (* OUTSIDE OF THE KERNEL OF THE LANG *)
316
317 (* EXAMPLES OF PASSES *)
318
319 (* loading object *)
320 module LoadObjects =
321 struct
322 module L = Lang.Ast
323 let load code k =
324 let extract_packages_decl = function
325 | L.Package (kind, name, pos) -> Some (kind, name, pos)
326 | _ -> None in
327 let extract_more_deps _ = StringMap.empty in
328 ObjectFiles.set_extrapaths ~no_stdlib:true !extrapaths;
329 let l = [(!current_filename,!current_content,code)] in
330 ObjectFiles.load ~no_stdlib:true extract_packages_decl extract_more_deps l
331 (function
332 | [(_,_,code)] -> k code
333 | _ -> assert false)
334 end
335
336 (* alpha renaming *)
337 module AlphaConv =
338 struct
339 module L = Lang.Ast
340 type env = int IntMap.t * int
341
342 (* separation *)
343 module S =
344 struct
345 (* keep the bigger index used for renaming variables *)
346 type t = int
347 let pass = "AlphaConv"
348 let pp = Format.pp_print_int
349 end
350 module R = ObjectFiles.Make(S)
351
352 let initial () =
353 let fold index t = max index t in
354 let index = R.fold fold 0 in
355 IntMap.empty, index
356
357 let expr env =
358 Lang.Walk.Expr.foldmap
359 (fun ((env, index) as acc) -> function
360 | L.K i -> if !bug_rewriting then acc, L.K (-1) else
361 begin
362 match IntMap.find_opt i env with
363 | None ->
364 let env = IntMap.add i index env in
365 (env, succ index), L.K index
366 | Some i ->
367 (env, index), L.K i
368 end
369 | t -> acc, t) env
370 let code_elt e = Lang.Walk.Elt.foldmap_nonrec expr e
371 let code e = Lang.Walk.Code.foldmap_nonrec expr e
372
373 let pass c =
374 let e = initial () in
375 let (_, i), c = code e c in
376 R.save i;
377 c
378 end
379
380 (*
381 dummy1 :
382 + K 0 => A
383 *)
384 module Dummy1 =
385 struct
386 module L = Lang.Ast
387 let (!!) v e = Lang.Error.context v e
388 let expr v =
389 Lang.Walk.Expr.map_up
390 (function
391 | (L.K _) as t when !bug_cond_violation_contradiction ->
392 Lang.Error.cond_violation Lang.Check.K_values.positives_id (!! v t) "contradiction"
393 | (L.K i) as t ->
394 (if !bug_allowed_cond_violation && (i < 0) then
395 Lang.Error.cond_violation Lang.Check.K_values.positives_id (!! v t) "%d < 0" i
396 );
397 if i = 0 then L.A else t
398 | t -> t)
399 let code_elt code_elt = Lang.Walk.Elt.map_nonrec (expr code_elt) code_elt
400 let code env = List.map code_elt env
401 end
402
403 (*
404 dummy2
405 + B (a, b) => B (9, b)
406 *)
407 module Dummy2 =
408 struct
409 module L = Lang.Ast
410 let (!!) v e = Lang.Error.context v e
411 let expr v =
412 Lang.Walk.Expr.map_up
413 (function
414 | (L.K i) as e ->
415 (if !bug_unbound_cond_violation && (i < 0) then
416 Lang.Error.scond_violation Lang.Check.K_values.positives_id (!! v e) "%d < 0" i
417 );
418 e
419 | L.B (_, b) -> L.B (L.K (if !bug_rewriting then (-9) else 9), b)
420 | t -> t)
421 let code_elt code_elt = Lang.Walk.Elt.map_nonrec (expr code_elt) code_elt
422 let code env = List.map code_elt env
423 end
424
425 module InsertTracker =
426 struct
427 module L = Lang.Ast
428
429 (* For the example, we add track at top level *)
430 let insert = List.map
431 (function
432 | L.Val (id, e) ->
433 let t = PassTracker.next id in
434 L.Val (id, L.Directive (t, e))
435 | c -> c
436 )
437 end
438
439 (*
440 Simulating the linking.
441 In compilation mode: store the code.
442 In linking mode: regroup all the code.
443 *)
444 module Linking =
445 struct
446
447 module S =
448 struct
449 type t = LangAst.code
450 let pass = "Linking"
451 let pp f _ = Format.pp_print_string f "<dummy>"
452 end
453 module R = ObjectFiles.Make(S)
454
455 let pass code =
456 match ObjectFiles.compilation_mode () with
457 | `compilation ->
458 OManager.unquiet "compilation of package @{<bright>%S@} ok." !current_filename;
459 R.save code;
460 OManager.exit 0
461 | `init ->
462 code
463 | `linking | `prelude ->
464 let fold (package_name,pos) code t =
465 OManager.verbose "linking with @{<bright>%s@}:%a" package_name FilePos.pp_pos pos ;
466 code @ t in
467 let full_parent_code = R.fold_with_name ~packages:true ~deep:true fold [] in
468 let full_code = full_parent_code @ code in
469 OManager.unquiet "linking ok.";
470 full_code
471 end
472
473 module S3Passes =
474 struct
475 module PH = PassHandler
476 module L = Lang.Ast
477 (* No parser, we use this : *)
478 let code () =
479 match !current_package_index with
480 | 1 ->
481 current_filename := "package-01.opa" ;
482 current_content := String.random 10 ;
483 [
484 L.Package (`declaration, "package-01", FilePos.nopos "position of declaration package-01") ;
485 L.Val ("toto", L.B (L.A, L.K 36)) ;
486 L.Val ("titi", L.B (L.K 5,
487 L.B (L.K 4,
488 L.B (L.A,
489 L.B (L.A,
490 L.B (L.K 5, L.K 0)
491 )
492 )
493 )
494 )
495 )
496 ]
497 | 2 ->
498 current_filename := "package-02.opa" ;
499 current_content := String.random 10 ;
500 [
501 L.Package (`declaration, "package-02", FilePos.nopos "position of declaration package-02") ;
502 L.Package (`import, "package-01", FilePos.nopos "position of import package-01") ;
503 L.Val ("toto", L.B (L.A, L.K 02)) ;
504 ]
505 | 3 ->
506 current_filename := "package-03.opa" ;
507 current_content := String.random 10 ;
508 [
509 L.Package (`declaration, "package-03", FilePos.nopos "position of declaration package-02") ;
510 L.Package (`import, "package-02", FilePos.nopos "position of import package-02") ;
511 L.Val ("toto", L.B (L.A, L.K 03)) ;
512 ]
513 | 4 ->
514 (* simulating the final linking *)
515 current_filename := "linking" ;
516 current_content := "nothing" ;
517 []
518 | _ -> assert false
519
520 let pass_Welcome () =
521 PH.make_pass
522 (fun _ ->
523 OManager.printf "Prototype compiler for testing new pass system@\n";
524 OManager.verbose "Compilation mode is %s" (
525 match ObjectFiles.compilation_mode () with
526 | `linking -> "linking"
527 | `init -> "init"
528 | `compilation -> "compilation"
529 | `prelude -> "prelude"
530 );
531 PassHandler.init
532 )
533
534 let pass_Parse () =
535 PH.make_pass
536 (fun env ->
537 { PH.
538 env = code ();
539 options = env.PH.options;
540 printers = (fun _ -> Lang.Track.printers);
541 trackers = (fun _ -> Lang.Track.trackers);
542 })
543
544 let pass_LoadObjects k =
545 PH.make_pass
546 (fun env ->
547 let env = LoadObjects.load env.PH.env (fun code -> k ( { env with PH.env = code })) in
548 PH.make_env () env
549 )
550
551 let pass_InsertTracker =
552 PH.make_pass
553 (fun env ->
554 { env with
555 PH.env = InsertTracker.insert env.PH.env
556 })
557
558 let pass_AlphaConv () =
559 let extract s = s in
560 let postcond =
561 [
562 Lang.Check.K_values.positives extract
563 ] in
564 PH.make_pass ~postcond
565 (fun env ->
566 let code = env.PH.env in
567 let code = AlphaConv.pass code in
568 { env with
569 PH.env = code
570 })
571
572 let pass_NotFound = PH.make_pass (fun _ -> raise Not_found)
573
574 let pass_Dummy1 =
575 let extract s = s in
576 let precond =
577 [
578 Lang.Check.K_values.positives extract
579 ] in
580 PH.make_pass ~precond
581 (fun env ->
582 { env with
583 PH.env = Dummy1.code env.PH.env
584 })
585
586 let pass_Dummy2 =
587 let extract s = s in
588 let postcond =
589 [
590 Lang.Check.K_values.positives extract
591 ] in
592 PH.make_pass ~postcond
593 (fun env ->
594 { env with
595 PH.env = Dummy2.code env.PH.env
596 })
597
598 let pass_Linking =
599 PH.make_pass
600 (fun env ->
601 { env with
602 PH.env = Linking.pass env.PH.env
603 })
604
605 let pass_Final _ =
606 PH.make_pass (
607 fun _ -> {
608 PH.
609 env = 0 ;
610 options = ();
611 printers =
612 (fun _ -> [
613 LangTrack.code_id,
614 (fun fmt i ->
615 Format.pp_print_int fmt i ;
616 Format.pp_print_char fmt '\n'
617 );
618 ]);
619 trackers = (fun _ -> []);
620 }
621 )
622
623 let pass_Exit _ =
624 PH.make_pass (
625 fun env ->
626 OManager.printf "exit %d\n" env.PH.env ;
627 { PH.
628 env = () ;
629 options = ();
630 printers =
631 (fun _ -> [
632 LangTrack.code_id,
633 (fun fmt () ->
634 Format.fprintf fmt "Compilation if over -- no more code to print\n"
635 );
636 ]) ;
637 trackers = (fun _ -> []) ;
638 }
639 )
640 end
641
642 module Main =
643 struct
644 module PH = PassHandler
645 module S3 = S3Passes
646 let (|>) a f = f a
647
648 let if_not_found ~options:_ _ = !bug_not_found
649
650 (* Normal style *)
651 let normal () =
652 PH.init
653 |> PH.handler "Welcome" (S3.pass_Welcome())
654 |> PH.handler "Parse" (S3.pass_Parse())
655 |> PH.handler "LoadObjects" (S3.pass_LoadObjects (fun e -> e
656 |> PH.handler "InsertTracker" S3.pass_InsertTracker
657 |> PH.handler "AlphaConv" (S3.pass_AlphaConv())
658 |> PH.if_handler ~if_:if_not_found "NotFound" S3.pass_NotFound
659 |> PH.handler "Dummy1" S3.pass_Dummy1
660 |> PH.handler "Dummy2" S3.pass_Dummy2
661 |> PH.handler "Linking" S3.pass_Linking
662 |> PH.handler "Final" (S3.pass_Final())
663 |> PH.handler "Exit" (S3.pass_Exit())
664 |> PH.return ))
665 |> PH.return
666
667 (* Binary operator style *)
668 let (|?>) = PassHandler.(|?>)
669 let (|+>) = PassHandler.(|+>)
670
671 let binop () =
672 PH.init
673 |+> ("Welcome" , S3.pass_Welcome() )
674 |+> ("Parse" , S3.pass_Parse() )
675 |+> ("LoadObjects" , S3.pass_LoadObjects (fun e -> e
676 |+> ("InsertTracker" , S3.pass_InsertTracker )
677 |+> ("AlphaConv" , S3.pass_AlphaConv() )
678 |?> (if_not_found,
679 "NotFound" , S3.pass_NotFound )
680 |+> ("Dummy1" , S3.pass_Dummy1 )
681 |+> ("Dummy2" , S3.pass_Dummy2 )
682 |+> ("Linking" , S3.pass_Linking )
683 |+> ("Final" , S3.pass_Final() )
684 |+> ("Exit" , S3.pass_Exit() )
685 |> PH.return ))
686 |> PH.return
687 end
688
689 let _ =
690 let bugs =
691 [
692
693 "--bug1",
694 Arg.Set bug_rewriting,
695 " Introduce some bug in a rewriting rule of the compilation. If the check is activated, this is detected as post condition failure, if not, nothing appends";
696
697
698 "--bug2",
699 Arg.Set bug_allowed_cond_violation,
700 " Introduce a cond violation detection during the compilation. If the check is activated, the pass is not executed, if not, the check is executed afterwards. Should be combined with --bug1 or not to test";
701
702
703 "--bug3",
704 Arg.Set bug_cond_violation_contradiction,
705 " Introduce a cond violation during the compilation, but so that for the checker point of vue the condition is not violated. If the check is activated, the pass is executed, if not the check is executed afterwards, in both case an explanation is given";
706
707
708 "--bug4",
709 Arg.Set bug_unbound_cond_violation,
710 " Introduce a rule declaring a cond violation where the cond is not in its preconditions should be combined with --bug1";
711
712
713 "--bug5",
714 Arg.Set bug_not_found,
715 " Introduce an uncaught exception during compilation (Not_found)";
716
717 "--file",
718 Arg.Symbol (["1"; "2"; "3"; "4"],
719 (fun s ->
720 current_package_index := int_of_string s
721 )),
722 " Tell what file to compile (testing separated compilation)"
723 ;
724
725 "-I",
726 Arg.String (fun s -> List.iter (fun p -> extrapaths := p :: !extrapaths) (Arg.split s)),
727 " Add extra path for loading packages"
728 ;
729
730 ] in
731
732 let _ =
733 Arg.parse
734 (Arg.align
735 (bugs
736 @ ObjectFiles.Arg.public_options
737 @ ObjectFiles.Arg.private_options
738 @ PassHandler.Arg.options
739 @ WarningClass.Arg.options ()
740 @ OManager.Arg.options
741 ))
742 ignore "passdesign" in
743 Main.binop ()
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