parsing_cocci/context_neg.ml

   1 (*
   2  * Copyright 2010, INRIA, University of Copenhagen
   3  * Julia Lawall, Rene Rydhof Hansen, Gilles Muller, Nicolas Palix
   4  * Copyright 2005-2009, Ecole des Mines de Nantes, University of Copenhagen
   5  * Yoann Padioleau, Julia Lawall, Rene Rydhof Hansen, Henrik Stuart, Gilles Muller, Nicolas Palix
   6  * This file is part of Coccinelle.
   7  *
   8  * Coccinelle is free software: you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License as published by
  10  * the Free Software Foundation, according to version 2 of the License.
  11  *
  12  * Coccinelle is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with Coccinelle.  If not, see <http://www.gnu.org/licenses/>.
  19  *
  20  * The authors reserve the right to distribute this or future versions of
  21  * Coccinelle under other licenses.
  22  *)
  23
  24
  25 (* Detects subtrees that are all minus/plus and nodes that are "binding
  26 context nodes".  The latter is a node whose structure and immediate tokens
  27 are the same in the minus and plus trees, and such that for every child,
  28 the set of context nodes in the child subtree is the same in the minus and
  29 plus subtrees. *)
  30
  31 module Ast = Ast_cocci
  32 module Ast0 = Ast0_cocci
  33 module V0 = Visitor_ast0
  34 module VT0 = Visitor_ast0_types
  35 module U = Unparse_ast0
  36
  37 (* --------------------------------------------------------------------- *)
  38 (* Generic access to code *)
  39
  40 let set_mcodekind x mcodekind =
  41   match x with
  42     Ast0.DotsExprTag(d) -> Ast0.set_mcodekind d mcodekind
  43   | Ast0.DotsInitTag(d) -> Ast0.set_mcodekind d mcodekind
  44   | Ast0.DotsParamTag(d) -> Ast0.set_mcodekind d mcodekind
  45   | Ast0.DotsStmtTag(d) -> Ast0.set_mcodekind d mcodekind
  46   | Ast0.DotsDeclTag(d) -> Ast0.set_mcodekind d mcodekind
  47   | Ast0.DotsCaseTag(d) -> Ast0.set_mcodekind d mcodekind
  48   | Ast0.IdentTag(d) -> Ast0.set_mcodekind d mcodekind
  49   | Ast0.ExprTag(d) -> Ast0.set_mcodekind d mcodekind
  50   | Ast0.ArgExprTag(d) | Ast0.TestExprTag(d) ->
  51       failwith "not possible - iso only"
  52   | Ast0.TypeCTag(d) -> Ast0.set_mcodekind d mcodekind
  53   | Ast0.ParamTag(d) -> Ast0.set_mcodekind d mcodekind
  54   | Ast0.DeclTag(d) -> Ast0.set_mcodekind d mcodekind
  55   | Ast0.InitTag(d) -> Ast0.set_mcodekind d mcodekind
  56   | Ast0.StmtTag(d) -> Ast0.set_mcodekind d mcodekind
  57   | Ast0.CaseLineTag(d) -> Ast0.set_mcodekind d mcodekind
  58   | Ast0.TopTag(d) -> Ast0.set_mcodekind d mcodekind
  59   | Ast0.IsoWhenTag(_) -> failwith "only within iso phase"
  60   | Ast0.IsoWhenTTag(_) -> failwith "only within iso phase"
  61   | Ast0.IsoWhenFTag(_) -> failwith "only within iso phase"
  62   | Ast0.MetaPosTag(p) -> failwith "metapostag only within iso phase"
  63
  64 let set_index x index =
  65   match x with
  66     Ast0.DotsExprTag(d) -> Ast0.set_index d index
  67   | Ast0.DotsInitTag(d) -> Ast0.set_index d index
  68   | Ast0.DotsParamTag(d) -> Ast0.set_index d index
  69   | Ast0.DotsStmtTag(d) -> Ast0.set_index d index
  70   | Ast0.DotsDeclTag(d) -> Ast0.set_index d index
  71   | Ast0.DotsCaseTag(d) -> Ast0.set_index d index
  72   | Ast0.IdentTag(d) -> Ast0.set_index d index
  73   | Ast0.ExprTag(d) -> Ast0.set_index d index
  74   | Ast0.ArgExprTag(d) | Ast0.TestExprTag(d) ->
  75       failwith "not possible - iso only"
  76   | Ast0.TypeCTag(d) -> Ast0.set_index d index
  77   | Ast0.ParamTag(d) -> Ast0.set_index d index
  78   | Ast0.InitTag(d) -> Ast0.set_index d index
  79   | Ast0.DeclTag(d) -> Ast0.set_index d index
  80   | Ast0.StmtTag(d) -> Ast0.set_index d index
  81   | Ast0.CaseLineTag(d) -> Ast0.set_index d index
  82   | Ast0.TopTag(d) -> Ast0.set_index d index
  83   | Ast0.IsoWhenTag(_) -> failwith "only within iso phase"
  84   | Ast0.IsoWhenTTag(_) -> failwith "only within iso phase"
  85   | Ast0.IsoWhenFTag(_) -> failwith "only within iso phase"
  86   | Ast0.MetaPosTag(p) -> failwith "metapostag only within iso phase"
  87
  88 let get_index = function
  89     Ast0.DotsExprTag(d) -> Index.expression_dots d
  90   | Ast0.DotsInitTag(d) -> Index.initialiser_dots d
  91   | Ast0.DotsParamTag(d) -> Index.parameter_dots d
  92   | Ast0.DotsStmtTag(d) -> Index.statement_dots d
  93   | Ast0.DotsDeclTag(d) -> Index.declaration_dots d
  94   | Ast0.DotsCaseTag(d) -> Index.case_line_dots d
  95   | Ast0.IdentTag(d) -> Index.ident d
  96   | Ast0.ExprTag(d) -> Index.expression d
  97   | Ast0.ArgExprTag(d) | Ast0.TestExprTag(d) ->
  98       failwith "not possible - iso only"
  99   | Ast0.TypeCTag(d) -> Index.typeC d
 100   | Ast0.ParamTag(d) -> Index.parameterTypeDef d
 101   | Ast0.InitTag(d) -> Index.initialiser d
 102   | Ast0.DeclTag(d) -> Index.declaration d
 103   | Ast0.StmtTag(d) -> Index.statement d
 104   | Ast0.CaseLineTag(d) -> Index.case_line d
 105   | Ast0.TopTag(d) -> Index.top_level d
 106   | Ast0.IsoWhenTag(_) -> failwith "only within iso phase"
 107   | Ast0.IsoWhenTTag(_) -> failwith "only within iso phase"
 108   | Ast0.IsoWhenFTag(_) -> failwith "only within iso phase"
 109   | Ast0.MetaPosTag(p) -> failwith "metapostag only within iso phase"
 110
 111 (* --------------------------------------------------------------------- *)
 112 (* Collect the line numbers of the plus code.  This is used for disjunctions.
 113 It is not completely clear why this is necessary, but it seems like an easy
 114 fix for whatever is the problem that is discussed in disj_cases *)
 115
 116 let plus_lines = ref ([] : int list)
 117
 118 let insert n =
 119   let rec loop = function
 120       [] -> [n]
 121     | x::xs ->
 122         match compare n x with
 123           1 -> x::(loop xs)
 124         | 0 -> x::xs
 125         | -1 -> n::x::xs
 126         | _ -> failwith "not possible" in
 127   plus_lines := loop !plus_lines
 128
 129 let find n min max =
 130   let rec loop = function
 131       [] -> (min,max)
 132     | [x] -> if n < x then (min,x) else (x,max)
 133     | x1::x2::rest ->
 134         if n < x1
 135         then (min,x1)
 136         else if n > x1 && n < x2 then (x1,x2) else loop (x2::rest) in
 137   loop !plus_lines
 138
 139 let collect_plus_lines top =
 140   plus_lines := [];
 141   let bind x y = () in
 142   let option_default = () in
 143   let donothing r k e = k e in
 144   let mcode (_,_,info,mcodekind,_,_) =
 145     match mcodekind with
 146       Ast0.PLUS _ -> insert info.Ast0.pos_info.Ast0.line_start
 147     | _ -> () in
 148   let fn =
 149     V0.flat_combiner bind option_default
 150       mcode mcode mcode mcode mcode mcode mcode mcode mcode mcode mcode mcode
 151       donothing donothing donothing donothing donothing donothing
 152       donothing donothing donothing donothing donothing donothing donothing
 153       donothing donothing in
 154   fn.VT0.combiner_rec_top_level top
 155
 156 (* --------------------------------------------------------------------- *)
 157
 158 type kind =
 159     Neutral | AllMarked of Ast.count | NotAllMarked (* marked means + or - *)
 160
 161 (* --------------------------------------------------------------------- *)
 162 (* The first part analyzes each of the minus tree and the plus tree
 163 separately *)
 164
 165 (* ints are unique token indices (offset field) *)
 166 type node =
 167     Token (* tokens *) of kind * int (* unique index *) * Ast0.mcodekind *
 168         int list (* context tokens *)
 169   | Recursor (* children *) of kind *
 170         int list (* indices of all tokens at the level below *) *
 171         Ast0.mcodekind list (* tokens at the level below *) *
 172         int list
 173   | Bind (* neighbors *) of kind *
 174         int list (* indices of all tokens at current level *) *
 175         Ast0.mcodekind list (* tokens at current level *) *
 176         int list (* indices of all tokens at the level below *) *
 177         Ast0.mcodekind list (* tokens at the level below *)
 178         * int list list
 179
 180 let kind2c = function
 181     Neutral -> "neutral"
 182   | AllMarked _ -> "allmarked"
 183   | NotAllMarked -> "notallmarked"
 184
 185 let node2c = function
 186     Token(k,_,_,_) -> Printf.sprintf "token %s\n" (kind2c k)
 187   | Recursor(k,_,_,_) -> Printf.sprintf "recursor %s\n" (kind2c k)
 188   | Bind(k,_,_,_,_,_) -> Printf.sprintf "bind %s\n" (kind2c k)
 189
 190 (* goal: detect negative in both tokens and recursors, or context only in
 191 tokens *)
 192 let bind c1 c2 =
 193   let lub = function
 194       (k1,k2) when k1 = k2 -> k1
 195     | (Neutral,AllMarked c) -> AllMarked c
 196     | (AllMarked c,Neutral) -> AllMarked c
 197     | _ -> NotAllMarked in
 198   match (c1,c2) with
 199     (* token/token *)
 200     (* there are tokens at this level, so ignore the level below *)
 201     (Token(k1,i1,t1,l1),Token(k2,i2,t2,l2)) ->
 202       Bind(lub(k1,k2),[i1;i2],[t1;t2],[],[],[l1;l2])
 203
 204     (* token/recursor *)
 205     (* there are tokens at this level, so ignore the level below *)
 206   | (Token(k1,i1,t1,l1),Recursor(k2,_,_,l2)) ->
 207       Bind(lub(k1,k2),[i1],[t1],[],[],[l1;l2])
 208   | (Recursor(k1,_,_,l1),Token(k2,i2,t2,l2)) ->
 209       Bind(lub(k1,k2),[i2],[t2],[],[],[l1;l2])
 210
 211     (* token/bind *)
 212     (* there are tokens at this level, so ignore the level below *)
 213   | (Token(k1,i1,t1,l1),Bind(k2,i2,t2,_,_,l2)) ->
 214       Bind(lub(k1,k2),i1::i2,t1::t2,[],[],l1::l2)
 215   | (Bind(k1,i1,t1,_,_,l1),Token(k2,i2,t2,l2)) ->
 216       Bind(lub(k1,k2),i1@[i2],t1@[t2],[],[],l1@[l2])
 217
 218     (* recursor/bind *)
 219   | (Recursor(k1,bi1,bt1,l1),Bind(k2,i2,t2,bi2,bt2,l2)) ->
 220       Bind(lub(k1,k2),i2,t2,bi1@bi2,bt1@bt2,l1::l2)
 221   | (Bind(k1,i1,t1,bi1,bt1,l1),Recursor(k2,bi2,bt2,l2)) ->
 222       Bind(lub(k1,k2),i1,t1,bi1@bi2,bt1@bt2,l1@[l2])
 223
 224     (* recursor/recursor and bind/bind - not likely to ever occur *)
 225   | (Recursor(k1,bi1,bt1,l1),Recursor(k2,bi2,bt2,l2)) ->
 226       Bind(lub(k1,k2),[],[],bi1@bi2,bt1@bt2,[l1;l2])
 227   | (Bind(k1,i1,t1,bi1,bt1,l1),Bind(k2,i2,t2,bi2,bt2,l2)) ->
 228       Bind(lub(k1,k2),i1@i2,t1@t2,bi1@bi2,bt1@bt2,l1@l2)
 229
 230
 231 let option_default = (*Bind(Neutral,[],[],[],[],[])*)
 232   Recursor(Neutral,[],[],[])
 233
 234 let mcode (_,_,info,mcodekind,pos,_) =
 235   let offset = info.Ast0.pos_info.Ast0.offset in
 236   match mcodekind with
 237     Ast0.MINUS(_) -> Token(AllMarked Ast.ONE,offset,mcodekind,[])
 238   | Ast0.PLUS c -> Token(AllMarked c,offset,mcodekind,[])
 239   | Ast0.CONTEXT(_) -> Token(NotAllMarked,offset,mcodekind,[offset])
 240   | _ -> failwith "not possible"
 241
 242 let neutral_mcode (_,_,info,mcodekind,pos,_) =
 243   let offset = info.Ast0.pos_info.Ast0.offset in
 244   match mcodekind with
 245     Ast0.MINUS(_) -> Token(Neutral,offset,mcodekind,[])
 246   | Ast0.PLUS _ -> Token(Neutral,offset,mcodekind,[])
 247   | Ast0.CONTEXT(_) -> Token(Neutral,offset,mcodekind,[offset])
 248   | _ -> failwith "not possible"
 249
 250 (* neutral for context; used for mcode in bef aft nodes that don't represent
 251 anything if they don't contain some information *)
 252 let nc_mcode (_,_,info,mcodekind,pos,_) =
 253   (* distinguish from the offset of some real token *)
 254   let offset = (-1) * info.Ast0.pos_info.Ast0.offset in
 255   match mcodekind with
 256     Ast0.MINUS(_) -> Token(AllMarked Ast.ONE,offset,mcodekind,[])
 257   | Ast0.PLUS c -> Token(AllMarked c,offset,mcodekind,[])
 258   | Ast0.CONTEXT(_) ->
 259       (* Unlike the other mcode cases, we drop the offset from the context
 260          offsets.  This is because we don't know whether the term this is
 261          associated with is - or context.  In any case, the context offsets are
 262          used for identification, and this invisible node should not be needed
 263          for this purpose. *)
 264       Token(Neutral,offset,mcodekind,[])
 265   | _ -> failwith "not possible"
 266
 267 let is_context = function Ast0.CONTEXT(_) -> true | _ -> false
 268
 269 let union_all l = List.fold_left Common.union_set [] l
 270
 271 (* is minus is true when we are processing minus code that might be
 272 intermingled with plus code.  it is used in disj_cases *)
 273 let classify is_minus all_marked table code =
 274   let mkres builder k il tl bil btl l e =
 275     (match k with
 276       AllMarked count ->
 277         Ast0.set_mcodekind e (all_marked count) (* definitive *)
 278     | _ ->
 279       let check_index il tl =
 280         if List.for_all is_context tl
 281         then
 282           (let e1 = builder e in
 283           let index = (get_index e1)@il in
 284           try
 285             let _ = Hashtbl.find table index in
 286             failwith
 287               (Printf.sprintf "line %d: index %s already used\n"
 288                  (Ast0.get_info e).Ast0.pos_info.Ast0.line_start
 289                  (String.concat " " (List.map string_of_int index)))
 290           with Not_found -> Hashtbl.add table index (e1,l)) in
 291       if il = [] then check_index bil btl else check_index il tl);
 292     if il = []
 293     then Recursor(k, bil, btl, union_all l)
 294     else Recursor(k, il, tl, union_all l) in
 295
 296   let compute_result builder e = function
 297       Bind(k,il,tl,bil,btl,l) -> mkres builder k il tl bil btl l e
 298     | Token(k,il,tl,l) -> mkres builder k [il] [tl] [] [] [l] e
 299     | Recursor(k,bil,btl,l) -> mkres builder k [] [] bil btl [l] e in
 300
 301   let make_not_marked = function
 302       Bind(k,il,tl,bil,btl,l) -> Bind(NotAllMarked,il,tl,bil,btl,l)
 303     | Token(k,il,tl,l) -> Token(NotAllMarked,il,tl,l)
 304     | Recursor(k,bil,btl,l) -> Recursor(NotAllMarked,bil,btl,l) in
 305
 306   let do_nothing builder r k e = compute_result builder e (k e) in
 307
 308   let disj_cases disj starter code fn ender =
 309     (* neutral_mcode used so starter and ender don't have an affect on
 310        whether the code is considered all plus/minus, but so that they are
 311        consider in the index list, which is needed to make a disj with
 312        something in one branch and nothing in the other different from code
 313        that just has the something (starter/ender enough, mids not needed
 314        for this).  Cannot agglomerate + code over | boundaries, because two -
 315        cases might have different + code, and don't want to put the + code
 316        together into one unit. *)
 317     let make_not_marked =
 318       if is_minus
 319       then
 320         (let min = Ast0.get_line disj in
 321         let max = Ast0.get_line_end disj in
 322         let (plus_min,plus_max) = find min (min-1) (max+1) in
 323         if max > plus_max then make_not_marked else (function x -> x))
 324       else make_not_marked in
 325     bind (neutral_mcode starter)
 326       (bind (List.fold_right bind
 327                (List.map make_not_marked (List.map fn code))
 328                option_default)
 329          (neutral_mcode ender)) in
 330
 331   (* no whencode in plus tree so have to drop it *)
 332   (* need special cases for dots, nests, and disjs *)
 333   let expression r k e =
 334     compute_result Ast0.expr e
 335       (match Ast0.unwrap e with
 336         Ast0.NestExpr(starter,exp,ender,whencode,multi) ->
 337           k (Ast0.rewrap e (Ast0.NestExpr(starter,exp,ender,None,multi)))
 338       | Ast0.Edots(dots,whencode) ->
 339           k (Ast0.rewrap e (Ast0.Edots(dots,None)))
 340       | Ast0.Ecircles(dots,whencode) ->
 341           k (Ast0.rewrap e (Ast0.Ecircles(dots,None)))
 342       | Ast0.Estars(dots,whencode) ->
 343           k (Ast0.rewrap e (Ast0.Estars(dots,None)))
 344       | Ast0.DisjExpr(starter,expr_list,_,ender) ->
 345           disj_cases e starter expr_list r.VT0.combiner_rec_expression ender
 346       | _ -> k e) in
 347
 348   (* not clear why we have the next two cases, since DisjDecl and
 349   DisjType shouldn't have been constructed yet, as they only come from isos *)
 350   let declaration r k e =
 351     compute_result Ast0.decl e
 352       (match Ast0.unwrap e with
 353         Ast0.DisjDecl(starter,decls,_,ender) ->
 354           disj_cases e starter decls r.VT0.combiner_rec_declaration ender
 355       | Ast0.Ddots(dots,whencode) ->
 356           k (Ast0.rewrap e (Ast0.Ddots(dots,None)))
 357         (* Need special cases for the following so that the type will be
 358            considered as a unit, rather than distributed around the
 359            declared variable.  This needs to be done because of the call to
 360            compute_result, ie the processing of each term should make a
 361            side-effect on the complete term structure as well as collecting
 362            some information about it.  So we have to visit each complete
 363            term structure.  In (all?) other such cases, we visit the terms
 364            using rebuilder, which just visits the subterms, rather than
 365            reordering their components. *)
 366       | Ast0.Init(stg,ty,id,eq,ini,sem) ->
 367           bind (match stg with Some stg -> mcode stg | _ -> option_default)
 368             (bind (r.VT0.combiner_rec_typeC ty)
 369                (bind (r.VT0.combiner_rec_ident id)
 370                   (bind (mcode eq)
 371                      (bind (r.VT0.combiner_rec_initialiser ini) (mcode sem)))))
 372       | Ast0.UnInit(stg,ty,id,sem) ->
 373           bind (match stg with Some stg -> mcode stg | _ -> option_default)
 374             (bind (r.VT0.combiner_rec_typeC ty)
 375                (bind (r.VT0.combiner_rec_ident id) (mcode sem)))
 376       | _ -> k e) in
 377
 378   let param r k e =
 379     compute_result Ast0.param e
 380       (match Ast0.unwrap e with
 381         Ast0.Param(ty,Some id) ->
 382           (* needed for the same reason as in the Init and UnInit cases *)
 383           bind (r.VT0.combiner_rec_typeC ty) (r.VT0.combiner_rec_ident id)
 384       | _ -> k e) in
 385
 386   let typeC r k e =
 387     compute_result Ast0.typeC e
 388       (match Ast0.unwrap e with
 389         Ast0.DisjType(starter,types,_,ender) ->
 390           disj_cases e starter types r.VT0.combiner_rec_typeC ender
 391       | _ -> k e) in
 392
 393   let initialiser r k i =
 394     compute_result Ast0.ini i
 395       (match Ast0.unwrap i with
 396         Ast0.Idots(dots,whencode) ->
 397           k (Ast0.rewrap i (Ast0.Idots(dots,None)))
 398       | _ -> k i) in
 399
 400   let case_line r k e =
 401     compute_result Ast0.case_line e
 402       (match Ast0.unwrap e with
 403         Ast0.DisjCase(starter,case_list,_,ender) ->
 404           disj_cases e starter case_list r.VT0.combiner_rec_case_line ender
 405       | _ -> k e) in
 406
 407   let statement r k s =
 408     compute_result Ast0.stmt s
 409       (match Ast0.unwrap s with
 410         Ast0.Nest(started,stm_dots,ender,whencode,multi) ->
 411           k (Ast0.rewrap s (Ast0.Nest(started,stm_dots,ender,[],multi)))
 412       | Ast0.Dots(dots,whencode) ->
 413           k (Ast0.rewrap s (Ast0.Dots(dots,[])))
 414       | Ast0.Circles(dots,whencode) ->
 415           k (Ast0.rewrap s (Ast0.Circles(dots,[])))
 416       | Ast0.Stars(dots,whencode) ->
 417           k (Ast0.rewrap s (Ast0.Stars(dots,[])))
 418       | Ast0.Disj(starter,statement_dots_list,_,ender) ->
 419           disj_cases s starter statement_dots_list r.VT0.combiner_rec_statement_dots
 420             ender
 421         (* cases for everything with extra mcode *)
 422       | Ast0.FunDecl((info,bef),_,_,_,_,_,_,_,_)
 423       | Ast0.Decl((info,bef),_) ->
 424           bind (nc_mcode ((),(),info,bef,(),-1)) (k s)
 425       | Ast0.IfThen(_,_,_,_,_,(info,aft))
 426       | Ast0.IfThenElse(_,_,_,_,_,_,_,(info,aft))
 427       | Ast0.Iterator(_,_,_,_,_,(info,aft))
 428       | Ast0.While(_,_,_,_,_,(info,aft))
 429       | Ast0.For(_,_,_,_,_,_,_,_,_,(info,aft)) ->
 430           bind (k s) (nc_mcode ((),(),info,aft,(),-1))
 431       | _ -> k s
 432
 433 ) in
 434
 435   let do_top builder r k e = compute_result builder e (k e) in
 436
 437   let combiner =
 438     V0.flat_combiner bind option_default
 439       mcode mcode mcode mcode mcode mcode mcode mcode mcode mcode mcode mcode
 440       (do_nothing Ast0.dotsExpr) (do_nothing Ast0.dotsInit)
 441       (do_nothing Ast0.dotsParam) (do_nothing Ast0.dotsStmt)
 442       (do_nothing Ast0.dotsDecl) (do_nothing Ast0.dotsCase)
 443       (do_nothing Ast0.ident) expression typeC initialiser param declaration
 444       statement case_line (do_top Ast0.top) in
 445   combiner.VT0.combiner_rec_top_level code
 446
 447 (* --------------------------------------------------------------------- *)
 448 (* Traverse the hash tables and find corresponding context nodes that have
 449 the same context children *)
 450
 451 (* this is just a sanity check - really only need to look at the top-level
 452    structure *)
 453 let equal_mcode (_,_,info1,_,_,_) (_,_,info2,_,_,_) =
 454   info1.Ast0.pos_info.Ast0.offset = info2.Ast0.pos_info.Ast0.offset
 455
 456 let equal_option e1 e2 =
 457   match (e1,e2) with
 458     (Some x, Some y) -> equal_mcode x y
 459   | (None, None) -> true
 460   | _ -> false
 461
 462 let dots fn d1 d2 =
 463   match (Ast0.unwrap d1,Ast0.unwrap d2) with
 464     (Ast0.DOTS(l1),Ast0.DOTS(l2)) -> List.length l1 = List.length l2
 465   | (Ast0.CIRCLES(l1),Ast0.CIRCLES(l2)) -> List.length l1 = List.length l2
 466   | (Ast0.STARS(l1),Ast0.STARS(l2)) -> List.length l1 = List.length l2
 467   | _ -> false
 468
 469 let rec equal_ident i1 i2 =
 470   match (Ast0.unwrap i1,Ast0.unwrap i2) with
 471     (Ast0.Id(name1),Ast0.Id(name2)) -> equal_mcode name1 name2
 472   | (Ast0.MetaId(name1,_,_),Ast0.MetaId(name2,_,_)) ->
 473       equal_mcode name1 name2
 474   | (Ast0.MetaFunc(name1,_,_),Ast0.MetaFunc(name2,_,_)) ->
 475       equal_mcode name1 name2
 476   | (Ast0.MetaLocalFunc(name1,_,_),Ast0.MetaLocalFunc(name2,_,_)) ->
 477       equal_mcode name1 name2
 478   | (Ast0.OptIdent(_),Ast0.OptIdent(_)) -> true
 479   | (Ast0.UniqueIdent(_),Ast0.UniqueIdent(_)) -> true
 480   | _ -> false
 481
 482 let rec equal_expression e1 e2 =
 483   match (Ast0.unwrap e1,Ast0.unwrap e2) with
 484     (Ast0.Ident(_),Ast0.Ident(_)) -> true
 485   | (Ast0.Constant(const1),Ast0.Constant(const2)) -> equal_mcode const1 const2
 486   | (Ast0.FunCall(_,lp1,_,rp1),Ast0.FunCall(_,lp2,_,rp2)) ->
 487       equal_mcode lp1 lp2 && equal_mcode rp1 rp2
 488   | (Ast0.Assignment(_,op1,_,_),Ast0.Assignment(_,op2,_,_)) ->
 489       equal_mcode op1 op2
 490   | (Ast0.CondExpr(_,why1,_,colon1,_),Ast0.CondExpr(_,why2,_,colon2,_)) ->
 491       equal_mcode why1 why2 && equal_mcode colon1 colon2
 492   | (Ast0.Postfix(_,op1),Ast0.Postfix(_,op2)) -> equal_mcode op1 op2
 493   | (Ast0.Infix(_,op1),Ast0.Infix(_,op2)) -> equal_mcode op1 op2
 494   | (Ast0.Unary(_,op1),Ast0.Unary(_,op2)) -> equal_mcode op1 op2
 495   | (Ast0.Binary(_,op1,_),Ast0.Binary(_,op2,_)) -> equal_mcode op1 op2
 496   | (Ast0.Paren(lp1,_,rp1),Ast0.Paren(lp2,_,rp2)) ->
 497       equal_mcode lp1 lp2 && equal_mcode rp1 rp2
 498   | (Ast0.ArrayAccess(_,lb1,_,rb1),Ast0.ArrayAccess(_,lb2,_,rb2)) ->
 499       equal_mcode lb1 lb2 && equal_mcode rb1 rb2
 500   | (Ast0.RecordAccess(_,pt1,_),Ast0.RecordAccess(_,pt2,_)) ->
 501       equal_mcode pt1 pt2
 502   | (Ast0.RecordPtAccess(_,ar1,_),Ast0.RecordPtAccess(_,ar2,_)) ->
 503       equal_mcode ar1 ar2
 504   | (Ast0.Cast(lp1,_,rp1,_),Ast0.Cast(lp2,_,rp2,_)) ->
 505       equal_mcode lp1 lp2 && equal_mcode rp1 rp2
 506   | (Ast0.SizeOfExpr(szf1,_),Ast0.SizeOfExpr(szf2,_)) ->
 507       equal_mcode szf1 szf2
 508   | (Ast0.SizeOfType(szf1,lp1,_,rp1),Ast0.SizeOfType(szf2,lp2,_,rp2)) ->
 509       equal_mcode szf1 szf2 && equal_mcode lp1 lp2 && equal_mcode rp1 rp2
 510   | (Ast0.TypeExp(_),Ast0.TypeExp(_)) -> true
 511   | (Ast0.MetaErr(name1,_,_),Ast0.MetaErr(name2,_,_))
 512   | (Ast0.MetaExpr(name1,_,_,_,_),Ast0.MetaExpr(name2,_,_,_,_))
 513   | (Ast0.MetaExprList(name1,_,_),Ast0.MetaExprList(name2,_,_)) ->
 514       equal_mcode name1 name2
 515   | (Ast0.EComma(cm1),Ast0.EComma(cm2)) -> equal_mcode cm1 cm2
 516   | (Ast0.DisjExpr(starter1,_,mids1,ender1),
 517      Ast0.DisjExpr(starter2,_,mids2,ender2)) ->
 518        equal_mcode starter1 starter2 &&
 519        List.for_all2 equal_mcode mids1 mids2 &&
 520        equal_mcode ender1 ender2
 521   | (Ast0.NestExpr(starter1,_,ender1,_,m1),
 522      Ast0.NestExpr(starter2,_,ender2,_,m2)) ->
 523       equal_mcode starter1 starter2 && equal_mcode ender1 ender2 && m1 = m2
 524   | (Ast0.Edots(dots1,_),Ast0.Edots(dots2,_))
 525   | (Ast0.Ecircles(dots1,_),Ast0.Ecircles(dots2,_))
 526   | (Ast0.Estars(dots1,_),Ast0.Estars(dots2,_)) -> equal_mcode dots1 dots2
 527   | (Ast0.OptExp(_),Ast0.OptExp(_)) -> true
 528   | (Ast0.UniqueExp(_),Ast0.UniqueExp(_)) -> true
 529   | _ -> false
 530
 531 let rec equal_typeC t1 t2 =
 532   match (Ast0.unwrap t1,Ast0.unwrap t2) with
 533     (Ast0.ConstVol(cv1,_),Ast0.ConstVol(cv2,_)) -> equal_mcode cv1 cv2
 534   | (Ast0.BaseType(ty1,stringsa),Ast0.BaseType(ty2,stringsb)) ->
 535       List.for_all2 equal_mcode stringsa stringsb
 536   | (Ast0.Signed(sign1,_),Ast0.Signed(sign2,_)) ->
 537       equal_mcode sign1 sign2
 538   | (Ast0.Pointer(_,star1),Ast0.Pointer(_,star2)) ->
 539       equal_mcode star1 star2
 540   | (Ast0.Array(_,lb1,_,rb1),Ast0.Array(_,lb2,_,rb2)) ->
 541       equal_mcode lb1 lb2 && equal_mcode rb1 rb2
 542   | (Ast0.EnumName(kind1,_),Ast0.EnumName(kind2,_)) ->
 543       equal_mcode kind1 kind2
 544   | (Ast0.StructUnionName(kind1,_),Ast0.StructUnionName(kind2,_)) ->
 545       equal_mcode kind1 kind2
 546   | (Ast0.FunctionType(ty1,lp1,p1,rp1),Ast0.FunctionType(ty2,lp2,p2,rp2)) ->
 547       equal_mcode lp1 lp2 && equal_mcode rp1 rp2
 548   | (Ast0.StructUnionDef(_,lb1,_,rb1),
 549      Ast0.StructUnionDef(_,lb2,_,rb2)) ->
 550        equal_mcode lb1 lb2 && equal_mcode rb1 rb2
 551   | (Ast0.TypeName(name1),Ast0.TypeName(name2)) -> equal_mcode name1 name2
 552   | (Ast0.MetaType(name1,_),Ast0.MetaType(name2,_)) ->
 553       equal_mcode name1 name2
 554   | (Ast0.DisjType(starter1,_,mids1,ender1),
 555      Ast0.DisjType(starter2,_,mids2,ender2)) ->
 556        equal_mcode starter1 starter2 &&
 557        List.for_all2 equal_mcode mids1 mids2 &&
 558        equal_mcode ender1 ender2
 559   | (Ast0.OptType(_),Ast0.OptType(_)) -> true
 560   | (Ast0.UniqueType(_),Ast0.UniqueType(_)) -> true
 561   | _ -> false
 562
 563 let equal_declaration d1 d2 =
 564   match (Ast0.unwrap d1,Ast0.unwrap d2) with
 565     (Ast0.MetaDecl(name1,_),Ast0.MetaDecl(name2,_))
 566   | (Ast0.MetaField(name1,_),Ast0.MetaField(name2,_)) ->
 567       equal_mcode name1 name2
 568   | (Ast0.Init(stg1,_,_,eq1,_,sem1),Ast0.Init(stg2,_,_,eq2,_,sem2)) ->
 569       equal_option stg1 stg2 && equal_mcode eq1 eq2 && equal_mcode sem1 sem2
 570   | (Ast0.UnInit(stg1,_,_,sem1),Ast0.UnInit(stg2,_,_,sem2)) ->
 571       equal_option stg1 stg2 && equal_mcode sem1 sem2
 572   | (Ast0.MacroDecl(nm1,lp1,_,rp1,sem1),Ast0.MacroDecl(nm2,lp2,_,rp2,sem2)) ->
 573       equal_mcode lp1 lp2 && equal_mcode rp1 rp2 && equal_mcode sem1 sem2
 574   | (Ast0.TyDecl(_,sem1),Ast0.TyDecl(_,sem2)) -> equal_mcode sem1 sem2
 575   | (Ast0.Ddots(dots1,_),Ast0.Ddots(dots2,_)) -> equal_mcode dots1 dots2
 576   | (Ast0.OptDecl(_),Ast0.OptDecl(_)) -> true
 577   | (Ast0.UniqueDecl(_),Ast0.UniqueDecl(_)) -> true
 578   | (Ast0.DisjDecl _,_) | (_,Ast0.DisjDecl _) ->
 579       failwith "DisjDecl not expected here"
 580   | _ -> false
 581
 582 let equal_designator d1 d2 =
 583   match (d1,d2) with
 584     (Ast0.DesignatorField(dot1,_),Ast0.DesignatorField(dot2,_)) ->
 585       equal_mcode dot1 dot2
 586   | (Ast0.DesignatorIndex(lb1,_,rb1),Ast0.DesignatorIndex(lb2,_,rb2)) ->
 587       (equal_mcode lb1 lb2) && (equal_mcode rb1 rb2)
 588   | (Ast0.DesignatorRange(lb1,_,dots1,_,rb1),
 589      Ast0.DesignatorRange(lb2,_,dots2,_,rb2)) ->
 590        (equal_mcode lb1 lb2) && (equal_mcode dots1 dots2) &&
 591        (equal_mcode rb1 rb2)
 592   | _ -> false
 593
 594 let equal_initialiser i1 i2 =
 595   match (Ast0.unwrap i1,Ast0.unwrap i2) with
 596     (Ast0.MetaInit(name1,_),Ast0.MetaInit(name2,_)) ->
 597       equal_mcode name1 name2
 598   | (Ast0.InitExpr(_),Ast0.InitExpr(_)) -> true
 599   | (Ast0.InitList(lb1,_,rb1),Ast0.InitList(lb2,_,rb2)) ->
 600       (equal_mcode lb1 lb2) && (equal_mcode rb1 rb2)
 601   | (Ast0.InitGccExt(designators1,eq1,_),
 602      Ast0.InitGccExt(designators2,eq2,_)) ->
 603        (List.for_all2 equal_designator designators1 designators2) &&
 604        (equal_mcode eq1 eq2)
 605   | (Ast0.InitGccName(_,eq1,_),Ast0.InitGccName(_,eq2,_)) ->
 606       equal_mcode eq1 eq2
 607   | (Ast0.IComma(cm1),Ast0.IComma(cm2)) -> equal_mcode cm1 cm2
 608   | (Ast0.Idots(d1,_),Ast0.Idots(d2,_)) -> equal_mcode d1 d2
 609   | (Ast0.OptIni(_),Ast0.OptIni(_)) -> true
 610   | (Ast0.UniqueIni(_),Ast0.UniqueIni(_)) -> true
 611   | _ -> false
 612
 613 let equal_parameterTypeDef p1 p2 =
 614   match (Ast0.unwrap p1,Ast0.unwrap p2) with
 615     (Ast0.VoidParam(_),Ast0.VoidParam(_)) -> true
 616   | (Ast0.Param(_,_),Ast0.Param(_,_)) -> true
 617   | (Ast0.MetaParam(name1,_),Ast0.MetaParam(name2,_))
 618   | (Ast0.MetaParamList(name1,_,_),Ast0.MetaParamList(name2,_,_)) ->
 619       equal_mcode name1 name2
 620   | (Ast0.PComma(cm1),Ast0.PComma(cm2)) -> equal_mcode cm1 cm2
 621   | (Ast0.Pdots(dots1),Ast0.Pdots(dots2))
 622   | (Ast0.Pcircles(dots1),Ast0.Pcircles(dots2)) -> equal_mcode dots1 dots2
 623   | (Ast0.OptParam(_),Ast0.OptParam(_)) -> true
 624   | (Ast0.UniqueParam(_),Ast0.UniqueParam(_)) -> true
 625   | _ -> false
 626
 627 let rec equal_statement s1 s2 =
 628   match (Ast0.unwrap s1,Ast0.unwrap s2) with
 629     (Ast0.FunDecl(_,fninfo1,_,lp1,_,rp1,lbrace1,_,rbrace1),
 630      Ast0.FunDecl(_,fninfo2,_,lp2,_,rp2,lbrace2,_,rbrace2)) ->
 631        (List.length fninfo1) = (List.length fninfo2) &&
 632        List.for_all2 equal_fninfo fninfo1 fninfo2 &&
 633        equal_mcode lp1 lp2 && equal_mcode rp1 rp2 &&
 634        equal_mcode lbrace1 lbrace2 && equal_mcode rbrace1 rbrace2
 635   | (Ast0.Decl(_,_),Ast0.Decl(_,_)) -> true
 636   | (Ast0.Seq(lbrace1,_,rbrace1),Ast0.Seq(lbrace2,_,rbrace2)) ->
 637       equal_mcode lbrace1 lbrace2 && equal_mcode rbrace1 rbrace2
 638   | (Ast0.ExprStatement(_,sem1),Ast0.ExprStatement(_,sem2)) ->
 639       equal_mcode sem1 sem2
 640   | (Ast0.IfThen(iff1,lp1,_,rp1,_,_),Ast0.IfThen(iff2,lp2,_,rp2,_,_)) ->
 641       equal_mcode iff1 iff2 && equal_mcode lp1 lp2 && equal_mcode rp1 rp2
 642   | (Ast0.IfThenElse(iff1,lp1,_,rp1,_,els1,_,_),
 643      Ast0.IfThenElse(iff2,lp2,_,rp2,_,els2,_,_)) ->
 644        equal_mcode iff1 iff2 &&
 645          equal_mcode lp1 lp2 && equal_mcode rp1 rp2 && equal_mcode els1 els2
 646   | (Ast0.While(whl1,lp1,_,rp1,_,_),Ast0.While(whl2,lp2,_,rp2,_,_)) ->
 647       equal_mcode whl1 whl2 && equal_mcode lp1 lp2 && equal_mcode rp1 rp2
 648   | (Ast0.Do(d1,_,whl1,lp1,_,rp1,sem1),Ast0.Do(d2,_,whl2,lp2,_,rp2,sem2)) ->
 649       equal_mcode whl1 whl2 && equal_mcode d1 d2 &&
 650       equal_mcode lp1 lp2 && equal_mcode rp1 rp2 && equal_mcode sem1 sem2
 651   | (Ast0.For(fr1,lp1,_,sem11,_,sem21,_,rp1,_,_),
 652      Ast0.For(fr2,lp2,_,sem12,_,sem22,_,rp2,_,_)) ->
 653        equal_mcode fr1 fr2 && equal_mcode lp1 lp2 &&
 654        equal_mcode sem11 sem12 && equal_mcode sem21 sem22 &&
 655        equal_mcode rp1 rp2
 656   | (Ast0.Iterator(nm1,lp1,_,rp1,_,_),Ast0.Iterator(nm2,lp2,_,rp2,_,_)) ->
 657       equal_mcode lp1 lp2 && equal_mcode rp1 rp2
 658   | (Ast0.Switch(switch1,lp1,_,rp1,lb1,_,_,rb1),
 659      Ast0.Switch(switch2,lp2,_,rp2,lb2,_,_,rb2)) ->
 660        equal_mcode switch1 switch2 && equal_mcode lp1 lp2 &&
 661        equal_mcode rp1 rp2 && equal_mcode lb1 lb2 &&
 662        equal_mcode rb1 rb2
 663   | (Ast0.Break(br1,sem1),Ast0.Break(br2,sem2)) ->
 664       equal_mcode br1 br2 && equal_mcode sem1 sem2
 665   | (Ast0.Continue(cont1,sem1),Ast0.Continue(cont2,sem2)) ->
 666       equal_mcode cont1 cont2 && equal_mcode sem1 sem2
 667   | (Ast0.Label(_,dd1),Ast0.Label(_,dd2)) ->
 668       equal_mcode dd1 dd2
 669   | (Ast0.Goto(g1,_,sem1),Ast0.Goto(g2,_,sem2)) ->
 670       equal_mcode g1 g2 && equal_mcode sem1 sem2
 671   | (Ast0.Return(ret1,sem1),Ast0.Return(ret2,sem2)) ->
 672       equal_mcode ret1 ret2 && equal_mcode sem1 sem2
 673   | (Ast0.ReturnExpr(ret1,_,sem1),Ast0.ReturnExpr(ret2,_,sem2)) ->
 674       equal_mcode ret1 ret2 && equal_mcode sem1 sem2
 675   | (Ast0.MetaStmt(name1,_),Ast0.MetaStmt(name2,_))
 676   | (Ast0.MetaStmtList(name1,_),Ast0.MetaStmtList(name2,_)) ->
 677       equal_mcode name1 name2
 678   | (Ast0.Disj(starter1,_,mids1,ender1),Ast0.Disj(starter2,_,mids2,ender2)) ->
 679       equal_mcode starter1 starter2 &&
 680       List.for_all2 equal_mcode mids1 mids2 &&
 681       equal_mcode ender1 ender2
 682   | (Ast0.Nest(starter1,_,ender1,_,m1),Ast0.Nest(starter2,_,ender2,_,m2)) ->
 683       equal_mcode starter1 starter2 && equal_mcode ender1 ender2 && m1 = m2
 684   | (Ast0.Exp(_),Ast0.Exp(_)) -> true
 685   | (Ast0.TopExp(_),Ast0.TopExp(_)) -> true
 686   | (Ast0.Ty(_),Ast0.Ty(_)) -> true
 687   | (Ast0.TopInit(_),Ast0.TopInit(_)) -> true
 688   | (Ast0.Dots(d1,_),Ast0.Dots(d2,_))
 689   | (Ast0.Circles(d1,_),Ast0.Circles(d2,_))
 690   | (Ast0.Stars(d1,_),Ast0.Stars(d2,_)) -> equal_mcode d1 d2
 691   | (Ast0.Include(inc1,name1),Ast0.Include(inc2,name2)) ->
 692       equal_mcode inc1 inc2 && equal_mcode name1 name2
 693   | (Ast0.Define(def1,_,_,_),Ast0.Define(def2,_,_,_)) ->
 694       equal_mcode def1 def2
 695   | (Ast0.OptStm(_),Ast0.OptStm(_)) -> true
 696   | (Ast0.UniqueStm(_),Ast0.UniqueStm(_)) -> true
 697   | _ -> false
 698
 699 and equal_fninfo x y =
 700   match (x,y) with
 701     (Ast0.FStorage(s1),Ast0.FStorage(s2)) -> equal_mcode s1 s2
 702   | (Ast0.FType(_),Ast0.FType(_)) -> true
 703   | (Ast0.FInline(i1),Ast0.FInline(i2)) -> equal_mcode i1 i2
 704   | (Ast0.FAttr(i1),Ast0.FAttr(i2)) -> equal_mcode i1 i2
 705   | _ -> false
 706
 707 let equal_case_line c1 c2 =
 708   match (Ast0.unwrap c1,Ast0.unwrap c2) with
 709     (Ast0.Default(def1,colon1,_),Ast0.Default(def2,colon2,_)) ->
 710       equal_mcode def1 def2 && equal_mcode colon1 colon2
 711   | (Ast0.Case(case1,_,colon1,_),Ast0.Case(case2,_,colon2,_)) ->
 712       equal_mcode case1 case2 && equal_mcode colon1 colon2
 713   | (Ast0.DisjCase(starter1,_,mids1,ender1),
 714      Ast0.DisjCase(starter2,_,mids2,ender2)) ->
 715        equal_mcode starter1 starter2 &&
 716        List.for_all2 equal_mcode mids1 mids2 &&
 717        equal_mcode ender1 ender2
 718   | (Ast0.OptCase(_),Ast0.OptCase(_)) -> true
 719   | _ -> false
 720
 721 let rec equal_top_level t1 t2 =
 722   match (Ast0.unwrap t1,Ast0.unwrap t2) with
 723     (Ast0.DECL(_),Ast0.DECL(_)) -> true
 724   | (Ast0.FILEINFO(old_file1,new_file1),Ast0.FILEINFO(old_file2,new_file2)) ->
 725       equal_mcode old_file1 old_file2 && equal_mcode new_file1 new_file2
 726   | (Ast0.CODE(_),Ast0.CODE(_)) -> true
 727   | (Ast0.ERRORWORDS(_),Ast0.ERRORWORDS(_)) -> true
 728   | _ -> false
 729
 730 let root_equal e1 e2 =
 731   match (e1,e2) with
 732     (Ast0.DotsExprTag(d1),Ast0.DotsExprTag(d2)) -> dots equal_expression d1 d2
 733   | (Ast0.DotsParamTag(d1),Ast0.DotsParamTag(d2)) ->
 734       dots equal_parameterTypeDef d1 d2
 735   | (Ast0.DotsStmtTag(d1),Ast0.DotsStmtTag(d2)) -> dots equal_statement d1 d2
 736   | (Ast0.DotsDeclTag(d1),Ast0.DotsDeclTag(d2)) -> dots equal_declaration d1 d2
 737   | (Ast0.DotsCaseTag(d1),Ast0.DotsCaseTag(d2)) -> dots equal_case_line d1 d2
 738   | (Ast0.IdentTag(i1),Ast0.IdentTag(i2)) -> equal_ident i1 i2
 739   | (Ast0.ExprTag(e1),Ast0.ExprTag(e2)) -> equal_expression e1 e2
 740   | (Ast0.ArgExprTag(d),_) -> failwith "not possible - iso only"
 741   | (Ast0.TypeCTag(t1),Ast0.TypeCTag(t2)) -> equal_typeC t1 t2
 742   | (Ast0.ParamTag(p1),Ast0.ParamTag(p2)) -> equal_parameterTypeDef p1 p2
 743   | (Ast0.InitTag(d1),Ast0.InitTag(d2)) -> equal_initialiser d1 d2
 744   | (Ast0.DeclTag(d1),Ast0.DeclTag(d2)) -> equal_declaration d1 d2
 745   | (Ast0.StmtTag(s1),Ast0.StmtTag(s2)) -> equal_statement s1 s2
 746   | (Ast0.TopTag(t1),Ast0.TopTag(t2)) -> equal_top_level t1 t2
 747   | (Ast0.IsoWhenTag(_),_) | (_,Ast0.IsoWhenTag(_))
 748   | (Ast0.IsoWhenTTag(_),_) | (_,Ast0.IsoWhenTTag(_))
 749   | (Ast0.IsoWhenFTag(_),_) | (_,Ast0.IsoWhenFTag(_)) ->
 750       failwith "only within iso phase"
 751   | _ -> false
 752
 753 let default_context _ =
 754   Ast0.CONTEXT(ref(Ast.NOTHING,
 755                    Ast0.default_token_info,Ast0.default_token_info))
 756
 757 let traverse minus_table plus_table =
 758   Hashtbl.iter
 759     (function key ->
 760       function (e,l) ->
 761         try
 762           let (plus_e,plus_l) = Hashtbl.find plus_table key in
 763           if root_equal e plus_e &&
 764             List.for_all (function x -> x)
 765               (List.map2 Common.equal_set l plus_l)
 766           then
 767             let i = Ast0.fresh_index() in
 768             (set_index e i; set_index plus_e i;
 769              set_mcodekind e (default_context());
 770              set_mcodekind plus_e (default_context()))
 771         with Not_found -> ())
 772     minus_table
 773
 774 (* --------------------------------------------------------------------- *)
 775 (* contextify the whencode *)
 776
 777 let contextify_all =
 778   let bind x y = () in
 779   let option_default = () in
 780   let mcode x = () in
 781   let do_nothing r k e = Ast0.set_mcodekind e (default_context()); k e in
 782
 783   V0.flat_combiner bind option_default
 784     mcode mcode mcode mcode mcode mcode mcode mcode mcode mcode mcode mcode
 785     do_nothing do_nothing do_nothing do_nothing do_nothing do_nothing
 786     do_nothing do_nothing do_nothing do_nothing do_nothing do_nothing
 787     do_nothing do_nothing do_nothing
 788
 789 let contextify_whencode =
 790   let bind x y = () in
 791   let option_default = () in
 792
 793   let expression r k e =
 794     k e;
 795     match Ast0.unwrap e with
 796       Ast0.NestExpr(_,_,_,Some whencode,_)
 797     | Ast0.Edots(_,Some whencode)
 798     | Ast0.Ecircles(_,Some whencode)
 799     | Ast0.Estars(_,Some whencode) ->
 800         contextify_all.VT0.combiner_rec_expression whencode
 801     | _ -> () in
 802
 803   let initialiser r k i =
 804     match Ast0.unwrap i with
 805       Ast0.Idots(dots,Some whencode) ->
 806         contextify_all.VT0.combiner_rec_initialiser whencode
 807     | _ -> k i in
 808
 809   let whencode = function
 810       Ast0.WhenNot sd -> contextify_all.VT0.combiner_rec_statement_dots sd
 811     | Ast0.WhenAlways s -> contextify_all.VT0.combiner_rec_statement s
 812     | Ast0.WhenModifier(_) -> ()
 813     | Ast0.WhenNotTrue(e) -> contextify_all.VT0.combiner_rec_expression e
 814     | Ast0.WhenNotFalse(e) -> contextify_all.VT0.combiner_rec_expression e in
 815
 816   let statement r k (s : Ast0.statement) =
 817     k s;
 818     match Ast0.unwrap s with
 819       Ast0.Nest(_,_,_,whn,_)
 820     | Ast0.Dots(_,whn) | Ast0.Circles(_,whn) | Ast0.Stars(_,whn) ->
 821         List.iter whencode whn
 822     | _ -> () in
 823
 824   let combiner =
 825     V0.combiner bind option_default
 826       {V0.combiner_functions with
 827         VT0.combiner_exprfn = expression;
 828         VT0.combiner_initfn = initialiser;
 829         VT0.combiner_stmtfn = statement} in
 830   combiner.VT0.combiner_rec_top_level
 831
 832 (* --------------------------------------------------------------------- *)
 833
 834 (* the first int list is the tokens in the node, the second is the tokens
 835 in the descendents *)
 836 let minus_table =
 837   (Hashtbl.create(50) : (int list, Ast0.anything * int list list) Hashtbl.t)
 838 let plus_table =
 839   (Hashtbl.create(50) : (int list, Ast0.anything * int list list) Hashtbl.t)
 840
 841 let iscode t =
 842   match Ast0.unwrap t with
 843     Ast0.DECL(_) -> true
 844   | Ast0.FILEINFO(_) -> true
 845   | Ast0.ERRORWORDS(_) -> false
 846   | Ast0.CODE(_) -> true
 847   | Ast0.OTHER(_) -> failwith "unexpected top level code"
 848
 849 (* ------------------------------------------------------------------- *)
 850 (* alignment of minus and plus *)
 851
 852 let concat = function
 853     [] -> []
 854   | [s] -> [s]
 855   | l ->
 856       let rec loop = function
 857           [] -> []
 858         | x::rest ->
 859             (match Ast0.unwrap x with
 860               Ast0.DECL(s) -> let stms = loop rest in s::stms
 861             | Ast0.CODE(ss) ->
 862                 let stms = loop rest in
 863                 (match Ast0.unwrap ss with
 864                   Ast0.DOTS(d) -> d@stms
 865                 | _ -> failwith "no dots allowed in pure plus code")
 866             | _ -> failwith "plus code is being discarded") in
 867       let res =
 868         Compute_lines.compute_statement_dots_lines false
 869           (Ast0.rewrap (List.hd l) (Ast0.DOTS (loop l))) in
 870       [Ast0.rewrap res (Ast0.CODE res)]
 871
 872 let collect_up_to m plus =
 873   let minfo = Ast0.get_info m in
 874   let mend = minfo.Ast0.pos_info.Ast0.logical_end in
 875   let rec loop = function
 876       [] -> ([],[])
 877     | p::plus ->
 878         let pinfo = Ast0.get_info p in
 879         let pstart = pinfo.Ast0.pos_info.Ast0.logical_start in
 880         if pstart > mend
 881         then ([],p::plus)
 882         else let (plus,rest) = loop plus in (p::plus,rest) in
 883   let (plus,rest) = loop plus in
 884   (concat plus,rest)
 885
 886 let realign minus plus =
 887   let rec loop = function
 888       ([],_) -> failwith "not possible, some context required"
 889     | ([m],p) -> ([m],concat p)
 890     | (m::minus,plus) ->
 891         let (p,plus) = collect_up_to m plus in
 892         let (minus,plus) = loop (minus,plus) in
 893         (m::minus,p@plus) in
 894   loop (minus,plus)
 895
 896 (* ------------------------------------------------------------------- *)
 897 (* check compatible: check that at the top level the minus and plus code is
 898 of the same kind.  Could go further and make the correspondence between the
 899 code between ...s. *)
 900
 901 let isonly f l = match Ast0.undots l with [s] -> f s | _ -> false
 902
 903 let isall f l = List.for_all (isonly f) l
 904
 905 let rec is_exp s =
 906   match Ast0.unwrap s with
 907     Ast0.Exp(e) -> true
 908   | Ast0.Disj(_,stmts,_,_) -> isall is_exp stmts
 909   | _ -> false
 910
 911 let rec is_ty s =
 912   match Ast0.unwrap s with
 913     Ast0.Ty(e) -> true
 914   | Ast0.Disj(_,stmts,_,_) -> isall is_ty stmts
 915   | _ -> false
 916
 917 let rec is_init s =
 918   match Ast0.unwrap s with
 919     Ast0.TopInit(e) -> true
 920   | Ast0.Disj(_,stmts,_,_) -> isall is_init stmts
 921   | _ -> false
 922
 923 let rec is_decl s =
 924   match Ast0.unwrap s with
 925     Ast0.Decl(_,e) -> true
 926   | Ast0.FunDecl(_,_,_,_,_,_,_,_,_) -> true
 927   | Ast0.Disj(_,stmts,_,_) -> isall is_decl stmts
 928   | _ -> false
 929
 930 let rec is_fndecl s =
 931   match Ast0.unwrap s with
 932     Ast0.FunDecl(_,_,_,_,_,_,_,_,_) -> true
 933   | Ast0.Disj(_,stmts,_,_) -> isall is_fndecl stmts
 934   | _ -> false
 935
 936 let rec is_toplevel s =
 937   match Ast0.unwrap s with
 938     Ast0.Decl(_,e) -> true
 939   | Ast0.FunDecl(_,_,_,_,_,_,_,_,_) -> true
 940   | Ast0.Disj(_,stmts,_,_) -> isall is_toplevel stmts
 941   | Ast0.ExprStatement(fc,_) ->
 942       (match Ast0.unwrap fc with
 943         Ast0.FunCall(_,_,_,_) -> true
 944       | _ -> false)
 945   | Ast0.Include(_,_) -> true
 946   | Ast0.Define(_,_,_,_) -> true
 947   | _ -> false
 948
 949 let check_compatible m p =
 950   let fail _ =
 951     failwith
 952       (Printf.sprintf
 953          "incompatible minus and plus code starting on lines %d and %d"
 954          (Ast0.get_line m) (Ast0.get_line p)) in
 955   match (Ast0.unwrap m, Ast0.unwrap p) with
 956     (Ast0.DECL(decl1),Ast0.DECL(decl2)) ->
 957       if not (is_decl decl1 && is_decl decl2)
 958       then fail()
 959   | (Ast0.DECL(decl1),Ast0.CODE(code2)) ->
 960       let v1 = is_decl decl1 in
 961       let v2 = List.for_all is_toplevel (Ast0.undots code2) in
 962       if !Flag.make_hrule = None && v1 && not v2 then fail()
 963   | (Ast0.CODE(code1),Ast0.DECL(decl2)) ->
 964       let v1 = List.for_all is_toplevel (Ast0.undots code1) in
 965       let v2 = is_decl decl2 in
 966       if v1 && not v2 then fail()
 967   | (Ast0.CODE(code1),Ast0.CODE(code2)) ->
 968       let v1 = isonly is_init code1 in
 969       let v2a = isonly is_init code2 in
 970       let v2b = isonly is_exp code2 in
 971       if v1
 972       then (if not (v2a || v2b) then fail())
 973       else
 974         let testers = [is_exp;is_ty] in
 975         List.iter
 976           (function tester ->
 977             let v1 = isonly tester code1 in
 978             let v2 = isonly tester code2 in
 979             if (v1 && not v2) or (!Flag.make_hrule = None && v2 && not v1)
 980             then fail())
 981           testers;
 982         let v1 = isonly is_fndecl code1 in
 983         let v2 = List.for_all is_toplevel (Ast0.undots code2) in
 984         if !Flag.make_hrule = None && v1 && not v2 then fail()
 985   | (Ast0.FILEINFO(_,_),Ast0.FILEINFO(_,_)) -> ()
 986   | (Ast0.OTHER(_),Ast0.OTHER(_)) -> ()
 987   | _ -> fail()
 988
 989 (* ------------------------------------------------------------------- *)
 990
 991 (* returns a list of corresponding minus and plus trees *)
 992 let context_neg minus plus =
 993   Hashtbl.clear minus_table;
 994   Hashtbl.clear plus_table;
 995   List.iter contextify_whencode minus;
 996   let (minus,plus) = realign minus plus in
 997   let rec loop = function
 998       ([],[]) -> []
 999     | ([],l) ->
1000         failwith (Printf.sprintf "%d plus things remaining" (List.length l))
1001     | (minus,[]) ->
1002         plus_lines := [];
1003         let _ =
1004           List.map
1005             (function m ->
1006               classify true
1007                 (function _ -> Ast0.MINUS(ref([],Ast0.default_token_info)))
1008                 minus_table m)
1009             minus in
1010         []
1011     | (((m::minus) as mall),((p::plus) as pall)) ->
1012         let minfo = Ast0.get_info m in
1013         let pinfo = Ast0.get_info p in
1014         let mstart = minfo.Ast0.pos_info.Ast0.logical_start in
1015         let mend = minfo.Ast0.pos_info.Ast0.logical_end in
1016         let pstart = pinfo.Ast0.pos_info.Ast0.logical_start in
1017         let pend = pinfo.Ast0.pos_info.Ast0.logical_end in
1018         if (iscode m or iscode p) &&
1019           (mend + 1 = pstart or pend + 1 = mstart or (* adjacent *)
1020            (mstart <= pstart && mend >= pstart) or
1021            (pstart <= mstart && pend >= mstart)) (* overlapping or nested *)
1022         then
1023           begin
1024             (* ensure that the root of each tree has a unique index,
1025                although it might get overwritten if the node is a context
1026                node *)
1027             let i = Ast0.fresh_index() in
1028             Ast0.set_index m i; Ast0.set_index p i;
1029             check_compatible m p;
1030             collect_plus_lines p;
1031             let _ =
1032               classify true
1033                 (function _ -> Ast0.MINUS(ref([],Ast0.default_token_info)))
1034                 minus_table m in
1035             let _ = classify false (function c -> Ast0.PLUS c) plus_table p in
1036             traverse minus_table plus_table;
1037             (m,p)::loop(minus,plus)
1038           end
1039         else
1040           if not(iscode m or iscode p)
1041           then loop(minus,plus)
1042           else
1043             if mstart < pstart
1044             then
1045               begin
1046                 plus_lines := [];
1047                 let _ =
1048                   classify true
1049                     (function _ -> Ast0.MINUS(ref([],Ast0.default_token_info)))
1050                     minus_table m in
1051                 loop(minus,pall)
1052               end
1053             else loop(mall,plus) in
1054   loop(minus,plus)