1 % (c) 2009-2025 Lehrstuhl fuer Softwaretechnik und Programmiersprachen,
2 % Heinrich Heine Universitaet Duesseldorf
3 % This software is licenced under EPL 1.0 (http://www.eclipse.org/org/documents/epl-v10.html)
4
5 :- module(bsyntaxtree,
6 [is_texpr/1, % checks if the given argument is a typed expression
7
8 get_texpr_expr/2, % get the expression part of a typed expression
9 get_texpr_type/2, % get the type of a typed expression
10 get_texpr_info/2, % get the list of information of a typed expression
11 get_texpr_id/2, % get the id of a typed identifier, fails if it's not an identifier
12 def_get_texpr_id/2, % same as above, but raises error if arg1 is not an identifier
13 def_get_texpr_ids/2, % maplist of the above, i.e., translate a typed id list into a plain list of id names
14 create_typed_id/3, % create a typed identifier
15 create_typed_ids/3, % create a list of typed identifiers from list of names and types
16 same_id/3, % true if two typed identifiers have the same id
17 same_ids/2, % true if two lists of typed identifiers have the same ids
18 same_ids_and_types/2, % also check types
19 split_names_and_types/3, % split list of typed ids into ids and types
20 get_texpr_exprs/2, % list variant of the above
21 get_texpr_types/2, % list variant of the above
22 get_texpr_infos/2, % list variant of the above
23 get_texpr_ids/2, % list variant of the above
24 get_texpr_pos/2, % get the position of a typed expression
25 extract_pos_infos/2, % get the position info sub list of an info list
26 copy_pos_infos/3, % copy position infos from one typed expression to another
27 delete_pos_info/2, % delete position info from an info list
28 propagate_pos_info_if_useful/3, % propagate position info from second list if useful
29 merge_info/3, % merge two information lists as well as possible
30 update_infos/3, % provide updates to an existing info list
31 get_info_pos/2, % get the position directly from info field
32 contains_info_pos/1, % true if info field contains position infos
33
34 same_texpr/2, % check if two typed expressions are equal modulo Info fields
35 different_texpr_values/2, % check if two type expressions are WD and definitely denote different values
36
37 create_texpr/4, % creates a typed expression by giving expression, type and infos
38 add_texpr_infos/3, % adds some more information to a typed expression at front
39 add_texpr_info_if_new/3, % adds one info field to typed B expression info list at front if it is new
40 add_texpr_infos_if_new/3, % ditto but list of infos can be added
41 add_info_if_new/3, % adds to info list
42 add_infos_if_new/3, % same for list of info items
43 safe_create_texpr/3, % a version of create_texpr which extracts wd-info from sub-expressionssafe_create_texpr
44 safe_create_texpr/4,
45 texpr_contains_wd_condition/1,
46 sub_expression_contains_wd_condition/1, % utility to check if sub-expression contains wd condition
47
48 get_rodin_name/2, get_rodin_model_name/2,
49 is_rodin_label_info/1,
50 get_texpr_label/2, get_texpr_labels/2,
51 get_info_labels/2, select_info_labels/3,
52 add_labels_to_texpr/3,
53 get_texpr_description/2, % get @desc pragma for typed expression
54 add_texpr_description/3, % add an additional description by hand
55 info_has_ignore_pragma/1, % check if an info list has an ignore pragma
56 predicate_has_ignore_pragma/1, % ditto for the info list of a predicate
57 always_well_defined/1, always_well_defined_or_disprover_mode/1,
58 always_well_defined_or_wd_reorderings_allowed/1,
59 always_well_defined_or_wd_improvements_allowed/1,
60 finite_wd_set_value/1, finite_set_or_disprover_mode/1,
61 is_truth/1, is_falsity/1,
62 conjunct_predicates/2,
63 conjunct_predicates_with_pos_info/3, conjunct_predicates_with_pos_info/2,
64 is_a_conjunct/3, is_a_conjunct_without_label/3, decompose_conjunct/3,
65 is_a_disjunct/3, is_an_implication/3, is_an_equivalence/3, is_a_negation/2,
66 conjunction_to_list/2,
67 conjunction_to_list_with_rodin_labels/2, % a variation which propagates labels down to conjuncts
68 member_in_conjunction/2, select_member_in_conjunction/3,
69 flatten_conjunctions/2,
70 size_of_conjunction/2,
71 member_in_conjunction_cse/3,
72 disjunct_predicates/2,
73 disjunct_predicates_with_pos_info/3,
74 disjunction_to_list/2,
75 is_a_disjunct_or_implication/4,
76 is_a_conjunct_or_neg_disj/3,
77
78 predicate_components/2, % split a predicate into components which use distinct identifiers
79 predicate_components_in_scope/3, % ditto with an optional list of local variables
80 predicate_components_with_restriction/4,
81 predicate_identifiers/2, predicate_identifiers_in_scope/3,
82
83 project_predicate_on_identifiers/5,
84
85 find_identifier_uses_top_level/2, % not including global sets and constants
86 find_identifier_uses/3, find_identifier_uses_if_necessary/3,
87 find_identifier_uses_l/3,
88 find_typed_identifier_uses/3,
89 find_typed_identifier_uses/2, % not including global sets and constants
90 find_typed_identifier_uses_l/3,
91 get_global_identifiers/1, get_global_identifiers/2,
92 occurs_in_expr/2, some_id_occurs_in_expr/2,
93 single_usage_identifier/3,
94 update_used_ids/3,
95 check_computed_used_ids/2,
96
97 create_exists/3, create_or_merge_exists/3,
98 create_exists_or_let_predicate/3,
99 create_exists_opt_liftable/3,
100 create_exists_opt/3, create_exists_opt/4, create_exists_opt/5,
101 create_forall/3,
102 create_negation/2, is_negation_of/2, get_negated_operator_expr/2,
103 create_implication/3,
104 create_equivalence/3,
105 is_equality/3,
106 create_equality/3, split_equality/3, get_texpr_couple/3,
107 create_couple/3, create_couple/2, nested_couple_to_list/2,
108 create_comprehension_set/4,
109 is_eventb_comprehension_set/4, is_eventb_comprehension_set/6,
110 singleton_set_extension/2,
111 is_membership/3, is_membership_or_equality/3,
112 get_lambda_equality/4,
113 is_pow_subset/2, is_pow1_subset/2,
114
115 detect_global_predicates/4,
116
117 definitely_not_empty_set/1, definitely_empty_set/1, definitely_not_empty_finite_value/1,
118 get_integer/2,
119 get_interval/3,
120
121 replace_id_by_expr/4,
122 replace_id_by_expr_with_count/5, % also count number of replacements
123 replace_ids_by_exprs/4,
124 remove_used_id_from_info/3, % remove an id from used_id info field if it exists
125 remove_used_ids_from_info/3, % remove list of ids (order of args different !)
126
127 rename_bt/3, % a simplified version of replace_ids_by_exprs, which assumes target of renamings are variables
128 rename_bt_l/3,
129 remove_bt/4,
130 syntaxtransformation/5,
131 syntaxtransformation_det/5, % faster, non-backtracking version
132
133 map_over_bexpr/2, map_over_typed_bexpr/2, map_over_typed_bexpr/3,
134 map_over_typed_bexpr_with_names/2,
135 map_over_bexpr_top_down_acc/3, map_over_typed_bexpr_top_down_acc/3,
136 reduce_over_bexpr/4,
137 transform_bexpr/3, % transform a typed B expression bottom-up
138 transform_bexpr_with_scoping/3, % ditto, but we also provide info about local ids
139 transform_bexpr_td_with_scoping/3, % top-down with scoping
140 transform_bexpr_with_bup_accs/5, transform_bexpr_with_acc/5,
141 non_det_transform_bexpr_with_acc/5, % can be used to generate several transformed expressions
142 uses_implementable_integers/1,
143 min_max_integer_value_used/3, min_max_integer_value_used/5,
144 syntaxtraversion/6,
145 safe_syntaxelement/5,
146 safe_syntaxelement_det/5, % a deterministic, non-backtracking version
147 is_subst_syntaxelement/1,
148 is_syntax_constant/1,
149
150 expand_all_lets/2,
151
152 remove_all_infos/2, extract_info/2, extract_info/3, extract_info_wo_used_ids/2,
153 bsyntax_pattern/2,
154
155 remove_all_infos_and_ground/2,
156
157 check_if_typed_predicate/1,
158 check_if_typed_expression/1,
159 check_if_typed_substitution/1,
160
161 strip_and_norm_ast/2,
162 same_norm_texpr/2,
163 get_texpr_functor/3,
164
165 is_set_type/2, get_set_type/2, get_texpr_set_type/2,
166 is_just_type/1, is_just_type/2,
167
168 create_recursive_compset/6,
169 unique_typed_id/3,
170 mark_bexpr_as_symbolic/2,
171
172 identifier_sub_ast/3, exchange_ast_position/5,
173
174 has_declared_identifier/2, add_declaration_for_identifier/3,
175 check_ast/1, check_ast/2,
176 repair_used_ids/3,
177 print_ast/1,
178 rewrite_if_then_else_expr_to_b/2
179 ]).
180
181 % meta_predicate annotations should appear before loading any code:
182
183 :- meta_predicate map_over_full_bexpr_no_fail(1,?).
184
185 :- meta_predicate map_over_bexpr(1,?).
186 :- meta_predicate map_over_typed_bexpr(1,?).
187 :- meta_predicate map_over_typed_bexpr(2,?,?).
188 :- meta_predicate map_over_bexpr_top_down_acc(3,?,?).
189 :- meta_predicate map_over_typed_bexpr_top_down_acc(3,?,?).
190
191 :- meta_predicate reduce_over_bexpr(3,?,?,?).
192 :- meta_predicate transform_bexpr(2,?,?).
193 :- meta_predicate l_transform_bexpr(?,2,?).
194 :- meta_predicate transform_bexpr_with_scoping(3,?,?).
195 :- meta_predicate transform_bexpr_td_with_scoping(3,?,?).
196 :- meta_predicate transform_bexpr_with_scoping2(3,?,?,?).
197 :- meta_predicate l_transform_bexpr_with_scoping(?,3,?,?).
198 :- meta_predicate transform_bexpr_with_bup_accs(4,?,?,?,?).
199 :- meta_predicate l_transform_bexpr_with_bup_accs(?,4,?,?,?).
200 :- meta_predicate transform_bexpr_with_acc(4,?,?,?,?).
201 :- meta_predicate l_transform_bexpr_with_acc(?,4,?,?,?).
202 :- meta_predicate non_det_transform_bexpr_with_acc(4,?,?,?,?).
203 :- meta_predicate l_nd_transform_bexpr_with_acc(?,4,?,?,?).
204
205 % -----------
206
207
208 :- use_module(tools).
209
210 :- use_module(module_information,[module_info/2]).
211 :- module_info(group,typechecker).
212 :- module_info(description,'This module provides operations on the type-checked AST.').
213
214 :- use_module(library(lists)).
215 :- use_module(library(ordsets)).
216 :- use_module(library(avl)).
217 :- use_module(library(terms)).
218
219 :- use_module(self_check).
220 :- use_module(error_manager).
221 :- use_module(translate,[print_bexpr/1,translate_bexpression/2]).
222 :- use_module(gensym,[gensym/2]).
223 :- use_module(preferences,[get_preference/2,preference/2]).
224 :- use_module(debug,[debug_mode/1,debug_format/3]).
225
226 :- use_module(typing_tools,[is_finite_type_in_context/2,normalize_type/2]).
227 :- use_module(tools_lists,[convlist_max/4]).
228
229 :- set_prolog_flag(double_quotes, codes).
230
231 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
232 % basic access to enriched syntax tree
233
234 is_texpr(b(_,_,_)).
235
236 get_texpr_expr(b(Name,_,_),R) :- !,R=Name.
237 get_texpr_expr(E,_) :- add_error_fail(get_texpr_expr,'B Expression not properly wrapped: ',E).
238
239 get_texpr_type(b(_,Type,_),R) :- !, R=Type.
240 get_texpr_type(E,_) :- add_error_fail(get_texpr_type,'B Expression not properly wrapped: ',E).
241 get_texpr_info(b(_,_,Info),R) :- !, R=Info.
242 get_texpr_info(E,_) :- add_error_fail(get_texpr_info,'B Expression not properly wrapped: ',E).
243
244 %! get_texpr_id(+Texpr,-Id)
245 get_texpr_id(b(N,_,_),Id) :- !, N=identifier(Id).
246 get_texpr_id(E,_) :- add_error_fail(get_texpr_id,'B Expression not properly wrapped: ',E).
247 /* same as above: but must succeed */
248 def_get_texpr_id(b(identifier(Id),_,_),R) :- !,R=Id.
249 def_get_texpr_id(b(E,_,_),_) :- !,
250 add_error_fail(def_get_texpr_id,'Could not extract identifier from typed expression: ',E).
251 def_get_texpr_id(ID,_) :- add_error_fail(def_get_texpr_id,'Could not extract identifier, not properly wrapped: ',ID).
252
253 % translate a list of ids with the b/3 wrapper into a plain id list; throw error if not an identifier
254 % used to also be called get_texpr_id_names
255 def_get_texpr_ids(L,Ids) :- maplist(def_get_texpr_id,L,Ids).
256
257 create_typed_id(IDName,Type,b(identifier(IDName),Type,[])).
258
259 create_typed_ids([],[],[]).
260 create_typed_ids([ID|TI],[Type|TT],[TID| TRes]) :-
261 create_typed_id(ID,Type,TID),
262 create_typed_ids(TI,TT,TRes).
263
264 same_id(X,Y,ID) :- get_texpr_id(X,ID), get_texpr_id(Y,ID).
265
266 same_ids([],[]).
267 same_ids([X|Xs],[Y|Ys]) :- same_id(X,Y,_), same_ids(Xs,Ys).
268
269 % check if two lists of identifiers have the same name and types
270 same_ids_and_types([],[]).
271 same_ids_and_types([b(identifier(Id),T1,_)|Xs],[b(identifier(Id),T2,_)|Ys]) :- unify_types_strict(T1,T2),
272 same_ids_and_types(Xs,Ys).
273
274 % split a list of typed identifiers into atomic ids and types
275 split_names_and_types([],N,T) :- !, N=[], T=[].
276 split_names_and_types([Identifier|IdRest],[Name|NRest],[Type|TRest]) :- !,
277 def_get_texpr_id(Identifier,Name),
278 get_texpr_type(Identifier,Type),
279 split_names_and_types(IdRest,NRest,TRest).
280 split_names_and_types(TIDS,N,R) :-
281 add_internal_error('Illegal call to:',split_names_and_types(TIDS,N,R)),fail.
282
283
284
285 % check if two wrapped expressions are equal (modulo associated Info, e.g. source loc info)
286 same_texpr(b(E1,Type,_),b(E2,Type,_)) :- % should we do a == check first ?? probably not as it may traverse the entire structure (see email exchange with SICStus 28.1.2015)
287 same_functor(E1,E2),
288 safe_syntaxelement_det(E1,Subs1,_Names1,_List1,Constant),
289 safe_syntaxelement_det(E2,Subs2,_Names2,_List2,Constant2),
290 Constant==Constant2, % in case we have values with variables inside !
291 same_sub_expressions(Subs1,Subs2).
292
293 same_sub_expressions([],[]).
294 same_sub_expressions([H1|T1],[H2|T2]) :- same_texpr(H1,H2), same_sub_expressions(T1,T2).
295
296 % check if two wrapped expressions definitely denote a different value (and are well-defined)
297 % only detects certain cases !
298 different_texpr_values(b(E1,Type,I1),b(E2,Type,I2)) :-
299 different_value(E1,E2,CheckWD),
300 (CheckWD=false -> true
301 ; always_well_defined_or_wd_improvements_allowed(b(E1,Type,I1)),
302 always_well_defined_or_wd_improvements_allowed(b(E2,Type,I2))).
303 different_value(boolean_false,boolean_true,false) :- !.
304 different_value(boolean_true,boolean_false,false) :- !.
305 different_value(integer(X),IY,false) :- get_integer_aux(IY,Y),!, X\=Y.
306 different_value(string(X),string(Y),false) :- !, X\=Y.
307 different_value(value(VX),Y,false) :- !, different_val_from(VX,Y).
308 different_value(empty_set,S,check_wd) :- !, non_empty_set(S).
309 different_value(S,empty_set,check_wd) :- !, non_empty_set(S).
310 % should we compare two set_extensions ? couples ? records ? reals?
311
312 different_val_from(Var,_) :- var(Var),!,fail.
313 different_val_from(int(X),IY) :- integer(X), get_integer_aux(IY,Y), X\=Y.
314 different_val_from(fd(X,Gs),value(FY)) :- nonvar(X), nonvar(FY), FY=fd(Y,Gs), nonvar(Y), X\=Y.
315 different_val_from(pred_false,boolean_true).
316 different_val_from(pred_false,value(BY)) :- BY==pred_true.
317 different_val_from(pred_true,boolean_false).
318 different_val_from(pred_true,value(BY)) :- BY==pred_false.
319 different_val_from(string(X),string(Y)) :- !, X\=Y.
320 different_val_from(string(X),value(VY)) :- nonvar(VY), VY=string(Y), nonvar(Y), !, X\=Y.
321 different_val_from(avl_set(node(_,_,_,_,_)),empty_set).
322
323 non_empty_set(set_extension([_|_])).
324 non_empty_set(sequence_extension([_|_])).
325
326
327 get_texpr_exprs([],[]).
328 get_texpr_exprs([E|Rest],[N|NRest]) :- get_texpr_expr(E,N),get_texpr_exprs(Rest,NRest).
329 get_texpr_exprs(b(E,_,_),Res) :- add_internal_error('Illegal call:',get_texpr_infos(b(E,_,_),Res)), Res=[E].
330 get_texpr_types([],[]).
331 get_texpr_types([E|Rest],[T|TRest]) :- get_texpr_type(E,T),get_texpr_types(Rest,TRest).
332 get_texpr_types(b(_,T,_),Res) :- add_internal_error('Illegal call:',get_texpr_infos(b(_,T,_),Res)), Res=[T].
333 get_texpr_infos([],[]).
334 get_texpr_infos([E|Rest],[I|IRest]) :- get_texpr_info(E,I),get_texpr_infos(Rest,IRest).
335 get_texpr_infos(b(_,_,I),Res) :- add_internal_error('Illegal call:',get_texpr_infos(b(_,_,I),Res)), Res=[I].
336 get_texpr_ids([],[]).
337 get_texpr_ids([E|Rest],[I|IRest]) :- get_texpr_id(E,I),get_texpr_ids(Rest,IRest).
338
339 get_texpr_pos(TExpr,Pos) :-
340 get_texpr_info(TExpr,Infos),
341 ? ( member(nodeid(Pos1),Infos) -> !,Pos=Pos1
342 ; Pos = none).
343
344 % similar to get_texpr_pos, but returns sub-list of infos relating to position
345 extract_pos_infos(Infos,InfoRes) :-
346 ? ( member(nodeid(Pos1),Infos) -> !,InfoRes=[nodeid(Pos1)]
347 ; InfoRes = []).
348
349 % copy position info from first arg to second argument
350 copy_pos_infos(b(_,_,Infos1),Arg2,Res) :-
351 member(nodeid(Pos1),Infos1),!,
352 Arg2 = b(E,T,Infos2), Res = b(E,T,Infos3),
353 delete_pos_info(Infos2,Infos2d),
354 Infos3 = [nodeid(Pos1)|Infos2d].
355 copy_pos_infos(_,TE,TE).
356
357 delete_pos_info(Infos1,Infos2) :-
358 select(nodeid(_),Infos1,D),!, Infos2=D.
359 %delete(Infos1,nodeid(_),Infos2).
360 delete_pos_info(I,I).
361
362 % propagate position info from second list to first one if it has better position info
363 propagate_pos_info_if_useful(Infos,AuxInfos,NewInfos) :-
364 member(nodeid(Pos2),AuxInfos),
365 \+ derived_pos(Pos2),!, % potentially useful position info to propagate
366 (select(nodeid(Pos1),Infos,Infos2)
367 -> (derived_pos(Pos1)
368 -> NewInfos = [nodeid(Pos2)|Infos2] % we have better position info now
369 ; NewInfos = Infos % we already have a position info
370 )
371 ; NewInfos = [nodeid(Pos2)|Infos]
372 ).
373 propagate_pos_info_if_useful(Infos,_,Infos).
374
375 % derived position; not precise instrinsic label at top-level
376 derived_pos(rodin_derived_context_pos(_,_,_)).
377
378
379 get_info_pos(Infos,Pos) :- (member(nodeid(Pos1),Infos) -> Pos=Pos1 ; Pos=none).
380 contains_info_pos(Infos) :- (member(nodeid(NI),Infos) -> NI \= none).
381
382 create_texpr(Expr,Type,Info,b(Expr,Type,Info)).
383
384 add_texpr_infos(b(Expr,Type,Old),Infos,b(Expr,Type,New)) :- !,
385 append(Infos,Old,New).
386 add_texpr_infos(Other,Infos,Res) :-
387 add_internal_error('Illegal call, not BExpr:',add_texpr_infos(Other,Infos,Res)),fail.
388
389 add_texpr_info_if_new(b(Expr,Type,Old),Info,b(Expr,Type,New)) :- !,
390 add_info_if_new(Old,Info,New).
391 add_texpr_info_if_new(Other,Infos,Res) :-
392 add_internal_error('Illegal call, not BExpr:',add_texpr_info_if_new(Other,Infos,Res)),fail.
393 % add multiple infos:
394 add_texpr_infos_if_new(b(Expr,Type,Old),Infos,b(Expr,Type,New)) :-
395 add_infos_if_new(Infos,Old,New).
396
397 % add to info list:
398 add_info_if_new(Old,Info,New) :-
399 (member(Info,Old) -> New=Old ; New = [Info|Old]).
400
401 add_infos_if_new([]) --> [].
402 add_infos_if_new([Info|T]) --> add_info(Info), add_infos_if_new(T).
403 add_info(Info,Old,New) :-
404 (member(Info,Old) -> New=Old ; New = [Info|Old]).
405
406
407 % try and extract the Rodin name of a predicate or expression
408 get_rodin_name(Expression,Name) :- get_texpr_pos(Expression,rodinpos(Name,_)), Name \= [].
409 get_rodin_name(Expression,Name) :- get_texpr_pos(Expression,rodinpos(_Model,Name,_)), Name \= []. % new rodinpos
410
411 get_rodin_model_name(Expression,Model) :-
412 get_texpr_pos(Expression,rodinpos(Model,Name,_)), Name \= []. % new rodinpos
413 % Note: only precise position label, not rodin_derived_context_pos
414
415 % try and extract the Rodin name or label pragma of a predicate or expression
416 get_texpr_labels(TExpr,Label) :-
417 get_texpr_info(TExpr,Infos),
418 member(I,Infos), info_label(I,Label).
419 get_info_labels(Infos,LabelList) :-
420 ? member(I,Infos), info_label(I,LabelList).
421 select_info_labels(LabelList,Infos,Rest) :-
422 select(I,Infos,Rest), info_label(I,LabelList).
423 info_label(nodeid(NodeID),[Name]) :- nodeid_info_label(NodeID,Name).
424 info_label(label(LabelList),LabelList).
425
426 nodeid_info_label(rodinpos(Name,_),Name) :- Name \= [].
427 nodeid_info_label(rodinpos(Model,Name,_),FullName) :- Name \= [], % new rodinpos
428 ajoin([Model,':',Name], FullName). % TO DO: if only one level; don't do this
429 % TODO: provide separate way to access this derived information:
430 %nodeid_info_label(rodin_derived_context_pos(Model,Context,Label),FullName) :-
431 % ajoin([Model,'.',Context,':',Label], FullName).
432
433
434 add_labels_to_texpr(E,[],R) :- !, R=E. % no labels to add
435 add_labels_to_texpr(b(E,T,I),Labels,b(E,T,NewI)) :-
436 (select(label(OldList),I,Rest)
437 -> append(Labels,OldList,NewList), NewI=[label(NewList)|Rest]
438 % TO DO: what if we have Rodin labels
439 ; NewI = [label(Labels)|I]
440 ).
441
442 get_texpr_label(TExpr,Label) :- get_texpr_labels(TExpr,Labels), member(Label,Labels).
443
444 get_texpr_description(TExpr,Description) :-
445 get_texpr_info(TExpr,Infos),
446 memberchk(description(Description),Infos).
447
448 add_texpr_description(b(E,T,I),Description,b(E,T,[description(Description)|I])) :-
449 (atom(Description) -> true ;
450 add_error(add_texpr_description,'Non-atomic description:',Description)).
451
452 % check if an info list has an ignore pragma
453 info_has_ignore_pragma(Infos) :-
454 member(description('prob-ignore'),Infos).
455 % detect_prob_ignore ast_cleanup rule also generates this description annotation
456
457 predicate_has_ignore_pragma(b(_E,pred,I)) :-
458 %add_message(check_prob_ignore,'Pred: ',b(_E,pred,I),I),
459 info_has_ignore_pragma(I).
460
461 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
462
463 :- assert_must_succeed( (E = "1/2",
464 bmachine:b_parse_machine_expression_from_codes(E,ET,Type,false,Err),
465 Type==integer, Err==none, always_well_defined(ET) ) ).
466 :- assert_must_succeed( (E = "3 mod 2",
467 bmachine:b_parse_machine_expression_from_codes(E,ET,Type,false,Err),
468 Type==integer, Err==none, always_well_defined(ET) ) ).
469 :- assert_must_succeed( (E = "1/0",
470 bmachine:b_parse_machine_expression_from_codes(E,ET,Type,false,Err),
471 Type==integer, Err==none, \+ always_well_defined(ET) ) ).
472 :- assert_must_succeed( (E = "2*(3 mod card({}))",
473 bmachine:b_parse_machine_expression_from_codes(E,ET,Type,false,Err),
474 Type==integer, Err==none, \+ always_well_defined(ET) ) ).
475 :- assert_must_succeed( (E = "1/(2+1-3)",
476 bmachine:b_parse_machine_expression_from_codes(E,ET,Type,false,Err),
477 Type==integer, Err==none, \+ always_well_defined(ET) ) ).
478 :- assert_must_succeed( (E = "max({1,2,3,0})",
479 bmachine:b_parse_machine_expression_from_codes(E,ET,Type,false,Err),
480 Type==integer, Err==none, always_well_defined(ET) ) ).
481 :- assert_must_succeed( (E = "min({1,2,3,0})",
482 bmachine:b_parse_machine_expression_from_codes(E,ET,Type,false,Err),
483 Type==integer, Err==none, always_well_defined(ET) ) ).
484 :- assert_must_succeed( (E = "min({1,2,3,0}-(0..4))",
485 bmachine:b_parse_machine_expression_from_codes(E,ET,Type,false,Err),
486 Type==integer, Err==none, \+ always_well_defined(ET) ) ).
487 :- assert_must_succeed( (E = "2+max({1,2,3, 1/0})",
488 bmachine:b_parse_machine_expression_from_codes(E,ET,Type,false,Err),
489 Type==integer, Err==none,\+ always_well_defined(ET) ) ).
490 :- assert_must_succeed( (E = "2-card({1,2,3})",
491 bmachine:b_parse_machine_expression_from_codes(E,ET,Type,false,Err),
492 Type==integer, Err==none, always_well_defined(ET) ) ).
493 :- assert_must_succeed( (E = "2-card({1,2,3, 1/0})",
494 bmachine:b_parse_machine_expression_from_codes(E,ET,Type,false,Err),
495 Type==integer, Err==none,\+ always_well_defined(ET) ) ).
496 :- assert_must_succeed( (E = "bool(2-size([1,2,3, 1/0])=3)",
497 bmachine:b_parse_machine_expression_from_codes(E,ET,Type,false,Err),
498 Type==boolean, Err==none, \+ always_well_defined(ET) ) ).
499 :- assert_must_succeed( (E = "bool(2-size([1,2,3, 1/2, 3 mod 2, 3**2])=size([]))",
500 bmachine:b_parse_machine_expression_from_codes(E,ET,Type,false,Err),
501 Type==boolean, Err==none, always_well_defined(ET) ) ).
502
503 always_well_defined_or_wd_reorderings_allowed(BE) :- % allow re-ordering to improve Left-to-right WD
504 (preferences:preference(disprover_mode,true) -> true % we can assume all calls are well-defined
505 ; preferences:preference(allow_improving_wd_mode,true) -> true
506 ; preferences:preference(data_validation_mode,true) -> true
507 ; always_well_defined_or_discharged(BE)).
508 always_well_defined_or_wd_improvements_allowed(BE) :- % allow to remove useless calls which could be non-WD
509 % example #x(x = f(...)) -> btrue or f[{}] --> {}
510 always_well_defined_or_wd_reorderings_allowed(BE). % we currently use the same definition
511 always_well_defined_or_disprover_mode(BE) :-
512 (preferences:preference(disprover_mode,true) -> true % we can assume all calls are well-defined
513 ; always_well_defined_or_discharged(BE)).
514
515 always_well_defined_or_discharged(b(E,_,Infos)) :- !,
516 (nonmember(contains_wd_condition,Infos) -> true
517 ; always_wd(E) -> true % some special rules
518 ; member(discharged_wd_po,Infos) -> true
519 %; nl, functor(E,F,N), F \= function, print(non_wd(F,N)),nl,nl,fail
520 ).
521 always_well_defined_or_discharged(E) :-
522 add_error_fail(always_well_defined,'Illegal call: ',always_well_defined_or_discharged(E)).
523
524 % should ensure that there is no failure and no error raised
525 always_well_defined(b(E,_,Infos)) :- !,
526 (nonmember(contains_wd_condition,Infos) -> true
527 ; always_wd(E) -> true % some special rules
528 %; nl, functor(E,F,N), F \= function, print(non_wd(F,N)),nl,nl,fail
529 ).
530 always_well_defined(E) :- add_error_fail(always_well_defined,'Illegal call: ',always_well_defined(E)).
531
532
533 :- assert_must_succeed( always_wd(div( b(integer(2),integer,[]), b(integer(2),integer,[]) )) ).
534 :- assert_must_fail( always_wd(div( b(integer(2),integer,[]), b(integer(0),integer,[]) )) ).
535 :- assert_must_succeed( always_wd(modulo( b(integer(2),integer,[]), b(integer(2),integer,[]) )) ).
536 :- assert_must_fail( always_wd(modulo( b(integer(2),integer,[]), b(integer(0),integer,[]) )) ).
537 :- assert_must_fail( always_wd(modulo( b(integer(2),integer,[]), b(integer(-2),integer,[]) )) ).
538 :- assert_must_fail( always_wd(modulo( b(integer(-1),integer,[]), b(integer(2),integer,[]) )) ).
539 :- assert_must_succeed( always_wd(power_of( b(integer(2),integer,[]), b(integer(3),integer,[]) )) ).
540 :- assert_must_succeed( always_wd(power_of( b(integer(2),integer,[]), b(integer(0),integer,[]) )) ).
541 :- assert_must_fail( always_wd(power_of( b(integer(2),integer,[]), b(integer(-1),integer,[]) )) ).
542
543 % catch cases where the construct is currently so instantiated that we can determine that it is well-defined
544 % can happen e.g. during closure compilation
545 :- use_module(custom_explicit_sets,[check_unique_in_domain_of_avlset/2]).
546 :- use_module(kernel_tools,[ground_value/1]).
547 always_wd(power_of(X,Y)) :- get_integer(Y,Val), Val>=0,
548 (eventb_mode -> get_integer(X,ValX), ValX >=0
549 ; always_well_defined(X)).
550 always_wd(div(X,Y)) :- get_integer(Y,Val), Val\=0, always_well_defined(X).
551 always_wd(modulo(X,Y)) :- get_integer(Y,Val), Val>0, % Z Live allows negative numbers here it seems, cf modulo2
552 (z_or_tla_minor_mode -> true % in Z, TLA we can have negative numbers here
553 ; get_integer(X,ValX), ValX>=0).
554 always_wd(function(X,Y)) :- nonvar(X),
555 X= b(value(AVLSET),_,_), nonvar(AVLSET), AVLSET=avl_set(AVL),
556 always_wd_avl_function(AVL,Y).
557 always_wd(min(X)) :- non_empty_finite_wd_set_value(X).
558 always_wd(max(X)) :- non_empty_finite_wd_set_value(X).
559 always_wd(card(X)) :- finite_wd_set_value(X).
560 always_wd(size(X)) :- finite_wd_seq_value(X).
561 always_wd(first(X)) :- non_empty_wd_seq_value(X).
562 always_wd(front(X)) :- non_empty_wd_seq_value(X).
563 always_wd(last(X)) :- non_empty_wd_seq_value(X).
564 always_wd(tail(X)) :- non_empty_wd_seq_value(X). % TO DO: add restrict_front, restrict_tail ?
565 always_wd(general_intersection(X)) :- non_empty_finite_wd_set_value(X).
566 always_wd(value(_)). % we have already computed the value and will raise WD error; to be 100 % safe we could restrict this to ground values
567 % other candidates: size(_), first(_) last(_) tail(_) front(_) restrict_front(_,_) restrict_tail(_,_) rel_iterate(_,_)
568 always_wd(typeset).
569 % operators that are always wd on their own:
570 always_wd(record_field(RecEx,FieldName)) :- ground(FieldName),
571 always_well_defined(RecEx).
572 always_wd(unary_minus(A)) :- always_well_defined(A).
573 always_wd(unary_minus_real(A)) :- always_well_defined(A).
574 always_wd(first_of_pair(A)) :- always_well_defined(A).
575 always_wd(add(A,B)) :- always_well_defined(A),always_well_defined(B).
576 always_wd(add_real(A,B)) :- always_well_defined(A),always_well_defined(B).
577 always_wd(minus(A,B)) :- always_well_defined(A),always_well_defined(B).
578 always_wd(minus_real(A,B)) :- always_well_defined(A),always_well_defined(B).
579 always_wd(multiplication(A,B)) :- always_well_defined(A),always_well_defined(B).
580 always_wd(multiplication_real(A,B)) :- always_well_defined(A),always_well_defined(B).
581 always_wd(equal(A,B)) :- always_well_defined(A),always_well_defined(B).
582 always_wd(not_equal(A,B)) :- always_well_defined(A),always_well_defined(B).
583 always_wd(less_equal(A,B)) :- always_well_defined(A),always_well_defined(B).
584 always_wd(less_equal_real(A,B)) :- always_well_defined(A),always_well_defined(B).
585 always_wd(greater_equal(A,B)) :- always_well_defined(A),always_well_defined(B).
586 always_wd(less(A,B)) :- always_well_defined(A),always_well_defined(B).
587 always_wd(less_real(A,B)) :- always_well_defined(A),always_well_defined(B).
588 always_wd(greater(A,B)) :- always_well_defined(A),always_well_defined(B).
589 always_wd(couple(A,B)) :- always_well_defined(A),always_well_defined(B).
590 % TO DO: add more/all other operators ?
591
592 always_wd_avl_function(AVL,Y) :- nonvar(Y), Y= b(value(Val),_,_),
593 ground_value(Val), !,
594 % Warning: this does not check that the whole AVL is a function; just this particular lookup is ok
595 check_unique_in_domain_of_avlset(Val,AVL). % ,print(ok),nl.
596 always_wd_avl_function(AVL,Y) :- always_well_defined(Y),
597 custom_explicit_sets:quick_definitely_maximal_total_function_avl(AVL).
598
599 % non empty set with WD elements
600 non_empty_finite_wd_set_value(b(E,_,_)) :- non_empty_fin_wd_set2(E).
601 non_empty_fin_wd_set2(bool_set).
602 non_empty_fin_wd_set2(value(X)) :- definitely_not_empty_finite_value(X).
603 non_empty_fin_wd_set2(set_extension(S)) :- l_always_well_defined(S). % the set_extension could contain wd_errors !!
604 non_empty_fin_wd_set2(sequence_extension(S)) :- l_always_well_defined(S). % ditto
605 non_empty_fin_wd_set2(interval(A,B)) :- get_integer(A,IA), get_integer(B,IB), IA =< IB.
606 % see not_empty_set_aux
607 definitely_not_empty_finite_value(X) :- var(X),!,fail.
608 definitely_not_empty_finite_value(avl_set(_)).
609 definitely_not_empty_finite_value([_|_]).
610 definitely_not_empty_finite_value(closure(P,T,B)) :-
611 custom_explicit_sets:is_interval_closure(P,T,B,LOW,UP), integer(LOW),integer(UP), LOW =< UP.
612 % TODO: pow_subset of finite values
613
614 non_empty_wd_seq_value(b(E,_,_)) :- non_empty_seq2(E).
615 non_empty_seq2(value(X)) :- definitely_not_empty_seq(X).
616 non_empty_seq2(sequence_extension(S)) :- l_always_well_defined(S), S=[_|_].
617
618 definitely_not_empty_seq(X) :- var(X),!,fail.
619 definitely_not_empty_seq(avl_set(A)) :- custom_explicit_sets:is_avl_sequence(A).
620 definitely_not_empty_seq([El1|T]) :- T==[],nonvar(El1), El1=(IDX,_), IDX==int(1). % TO DO: add more cases ?
621
622
623 finite_set_or_disprover_mode(Set) :-
624 (preferences:preference(disprover_mode,true) -> true % we can assume all calls are well-defined
625 ; finite_wd_set_value(Set)).
626
627 :- use_module(typing_tools,[is_provably_finite_type/1]).
628 % we could also use is_finite_type_in_context to allow deferred sets to be counted as finite
629 finite_wd_set_value(b(E,T,_)) :- !, (finite_set2(E) -> true ; is_provably_finite_type(T)).
630 finite_wd_set_value(E) :- add_internal_error('Not a BExpr: ',E),fail.
631 finite_set2(empty_set).
632 finite_set2(empty_sequence).
633 finite_set2(value(X)) :- X==[] -> true ; definitely_not_empty_finite_value(X).
634 finite_set2(set_extension(S)) :- l_always_well_defined(S). % the set_extension could contain wd_errors !!
635 finite_set2(sequence_extension(S)) :- l_always_well_defined(S). % ditto
636
637 finite_wd_seq_value(b(E,_,_)) :- finite_seq2(E).
638 finite_seq2(empty_set).
639 finite_seq2(empty_sequence).
640 finite_seq2(value(X)) :- finite_seq_value(X).
641 finite_seq2(sequence_extension(S)) :- l_always_well_defined(S).
642
643 finite_seq_value(X) :- var(X),!,fail.
644 finite_seq_value([]).
645 finite_seq_value(avl_set(A)) :- custom_explicit_sets:is_avl_sequence(A).
646 % it could be expensive to check if non empty list is a B sequence ??
647
648 l_always_well_defined([]).
649 l_always_well_defined([H|T]) :- always_well_defined(H), l_always_well_defined(T).
650
651 is_truth(b(F,pred,_)) :- is_truth_aux(F).
652 is_truth_aux(truth).
653 is_truth_aux(value(V)) :- V==pred_true. % can occur in CSE mode
654
655 is_falsity(b(F,pred,_)) :- is_falsity_aux(F).
656 is_falsity_aux(falsity).
657 is_falsity_aux(value(V)) :- V==pred_false. % can occur in CSE mode
658
659 % conjunction of a list of predicates
660 % NOTE: bsyntaxtree:conjunct_predicates([P1,P2,P3],R). --> generates R = b(conjunct(b(conjunct(P1,P2),pred,[]),P3),pred,[])
661 conjunct_predicates(V,R) :- var(V),!, add_internal_error('Variable conjunction list: ',conjunct_predicates(V,R)),fail.
662 conjunct_predicates([],b(truth,pred,[])).
663 conjunct_predicates([P|Rest],Result) :- conjunct2(Rest,P,Result).
664 conjunct2([],P,P).
665 conjunct2([Q|Rest],P,Result) :- conjunct3(P,Q,R), conjunct2(Rest,R,Result).
666 conjunct3(b(truth,_,_),P,P) :- !.
667 conjunct3(P,b(truth,_,_),P) :- !.
668 conjunct3(A,B,b(conjunct(A,B),pred,NewInfo)) :- extract_info(A,B,NewInfo).
669
670 % disjunction of a list of predicates
671 disjunct_predicates([],b(falsity,pred,[])).
672 disjunct_predicates([P|Rest],Result) :- disjunct2(Rest,P,Result).
673 disjunct2([],P,P).
674 disjunct2([Q|Rest],P,Result) :- disjunct3(P,Q,R), disjunct2(Rest,R,Result).
675 disjunct3(b(falsity,_,_),P,R) :- !, R=P.
676 disjunct3(b(truth,T,I),_,R) :- !, R=b(truth,T,I).
677 disjunct3(P,b(falsity,_,_),R) :- !, R=P.
678 disjunct3(_,b(truth,T,I),R) :- !, R=b(truth,T,I).
679 disjunct3(A,B,b(disjunct(A,B),pred,NewInfo)) :- extract_info(A,B,NewInfo).
680
681 % conjunct two predicates and try and construct position information
682 conjunct_predicates_with_pos_info(A,B,AB) :- is_truth(B),!, AB=A.
683 conjunct_predicates_with_pos_info(A,B,AB) :- is_truth(A),!, AB=B.
684 conjunct_predicates_with_pos_info(A,B,AB) :-
685 conjunct_predicates([A,B],AB0), % this may contain position info if B is truth; hence we do check above
686 (try_get_merged_position_info(A,B,ABI)
687 -> add_texpr_infos(AB0,[ABI],AB) %,print(abi(ABI)),nl
688 ; AB=AB0).
689
690 % disjunct two predicates and try and construct position information
691 disjunct_predicates_with_pos_info(A,B,AB) :-
692 disjunct_predicates([A,B],AB0),
693 (try_get_merged_position_info(A,B,ABI)
694 -> add_texpr_infos(AB0,[ABI],AB) %,print(abi(ABI)),nl
695 ; AB=AB0).
696
697 try_get_merged_position_info(b(_,_,I1),b(_,_,I2),PosInfo) :-
698 (try_get_merged_position_info_aux(I1,I2,MergedInfo) -> PosInfo = MergedInfo
699 ; get_non_label_posinfo(Pos1,I1) -> PosInfo=nodeid(Pos1)
700 ; get_non_label_posinfo(Pos2,I2) -> PosInfo=nodeid(Pos2)
701 ).
702 try_get_merged_position_info_aux(I1,I2,nodeid(pos(C,Filenumber,Srow,Scol,Erow,Ecol))) :-
703 member(nodeid(pos(C1,Filenumber,Srow1,Scol1,Erow1,Ecol1)),I1),
704 (number(C1),number(Srow1),number(Scol1),number(Erow1),number(Ecol1)
705 -> true ; add_internal_error('Info field 1 not yet instantiated: ',try_get_merged_position_info(I1)),fail),
706 !,
707 member(nodeid(pos(C2,Filenumber,Srow2,Scol2,Erow2,Ecol2)),I2),
708 (number(C2),number(Srow2),number(Scol2),number(Erow2),number(Ecol2)
709 -> true ; add_internal_error('Info field 2 not yet instantiated: ',try_get_merged_position_info(I2)),fail),
710 !,
711 % merge position info if in same file
712 (C1 =< C2 -> C=C1, Srow=Srow1,Scol=Scol1 ; C=C2, Srow=Srow2,Scol=Scol2),
713 ((Erow1 > Erow2 ; Erow1=Erow2, Ecol1 >= Ecol2)
714 -> Erow =Erow1, Ecol=Ecol1
715 ; Erow =Erow2, Ecol=Ecol2).
716
717 % get position info which is not a label; label info should not be propagated to outer conjuncts/disjuncts/...
718 get_non_label_posinfo(Pos,Infos) :- member(nodeid(Pos),Infos),
719 \+ functor(Pos,rodinpos,_).
720
721 get_texpr_non_label_posinfo(b(_,_,Infos),nodeid(Pos)) :- get_non_label_posinfo(Pos,Infos).
722
723 % conjunct list of predicates and try and construct position information
724 conjunct_predicates_with_pos_info([H|T],Res) :- is_truth(H),!,
725 (T=[] -> Res = H ; conjunct_predicates_with_pos_info(T,Res)).
726 conjunct_predicates_with_pos_info([H|T],Res) :-
727 last_non_truth(T,none,Last), % the truth elements will be removed and are not relevant; get last relevant predicate
728 Last \= none,
729 try_get_merged_position_info(H,Last,MergedPosInfo), % try and merge position of first and last element
730 !,
731 conjunct_predicates([H|T],Res0),
732 add_texpr_infos(Res0,[MergedPosInfo],Res). % Res0 should have no nodeid field
733 conjunct_predicates_with_pos_info(L,Res) :- conjunct_predicates(L,Res).
734
735 :- assert_must_succeed((bsyntaxtree:last_non_truth([a,b,c],none,L),L==c)).
736 :- assert_must_succeed((bsyntaxtree:last_non_truth([a,b,c,b(truth,pred,[])],none,L),L==c)).
737
738 % get last non-truth element and filter out all truth elements
739 last_non_truth([],Acc,Acc).
740 last_non_truth([H|T],NonTruth,Last) :- is_truth(H),!, last_non_truth(T,NonTruth,Last).
741 last_non_truth([H|T],_,Last) :- last_non_truth(T,H,Last).
742
743
744 texpr_contains_wd_condition(b(_,_,Info)) :- !, memberchk(contains_wd_condition,Info).
745 texpr_contains_wd_condition(E) :- add_internal_error('Not a texpr: ',texpr_contains_wd_condition(E)).
746
747 % a version of create_texpr which collects automatically important infos from sub-expressions
748 safe_create_texpr(Expr,Type,b(Expr,Type,Info)) :- %
749 ? (sub_expression_contains_wd_condition(Expr) -> Info = [contains_wd_condition] ; Info=[]).
750
751 safe_create_texpr(Expr,Type,Info,b(Expr,Type,FullInfo)) :- %
752 ((sub_expression_contains_wd_condition(Expr), nonmember(contains_wd_condition, Info)) -> FullInfo = [contains_wd_condition|Info] ; FullInfo=Info).
753
754 ?sub_expression_contains_wd_condition(Expr) :- sub_expression_contains_wd_condition(Expr,_).
755 sub_expression_contains_wd_condition(Expr,Sub) :-
756 safe_syntaxelement_det(Expr,Subs,_Names,_L,_C),
757 ? member(b(Sub,_,Infos),Subs),
758 (var(Infos)
759 -> add_internal_error('Typed expression not sufficiently instantiated (variable Infos): ',sub_expression_contains_wd_condition(Expr)),
760 fail
761 ; memberchk(contains_wd_condition,Infos)).
762
763 % provide updated infos (e.g., reads(...)) and remove any old info fields with same functor
764 update_infos([],Infos,Infos).
765 update_infos([Update|T],OldInfos,NewInfos) :-
766 functor(Update,F,N),
767 functor(Old,F,N),
768 delete(OldInfos,Old,OldInfos1),
769 update_infos(T,[Update|OldInfos1],NewInfos).
770
771 % merge two info lists and try to reconcile position information:
772 merge_info(Info1,Info2,Res) :-
773 merge_imp_info2(Info2,Info1,NewInfo),
774 (try_get_merged_position_info_aux(Info1,Info2,NewPos)
775 -> delete_pos_info(NewInfo,NI2),
776 Res = [NewPos|NI2]
777 ; Res = NewInfo).
778
779 % extract important info but without used_ids:
780 extract_info_wo_used_ids(b(_,_,Info1),Info) :-
781 extract_pos_infos(Info1,PosInfos),
782 extract_just_important_info_aux(Info1,[],I1),
783 append(PosInfos,I1,Info).
784 extract_info_wo_used_ids_and_pos(b(_,_,Info1),b(_,_,Info2),Info) :-
785 extract_just_important_info_aux(Info1,[],I1),
786 extract_just_important_info_aux(Info2,I1,Info).
787
788 % extract important info from one sub-expression:
789 extract_info(b(_,_,Info1),NewInfo) :-
790 extract_imp_info1(Info1,I1),!, NewInfo = I1.
791 extract_info(A,R) :-
792 add_internal_error('Could not extract info: ',extract_info(A,R)),
793 R=[].
794 % extract imortant info fields from two (sub-)expressions
795 extract_info(b(_,_,Info1),b(_,_,Info2),NewInfo) :-
796 merge_imp_info2(Info1,Info2,II),!, NewInfo = II.
797 %:- use_module(library(ordsets),[ord_intersection/3]).
798 % ord_intersection(Info1,Info2,NewInfo),!.
799 % TO DO: should we merge nodeid position information !?
800 extract_info(A,B,R) :- add_internal_error('Could not extract info: ',extract_info(A,B,R)),
801 R=[].
802
803 % extract important info and used_ids
804 extract_imp_info1([],[]).
805 extract_imp_info1([H|T],Res) :-
806 ((important_info(H); H=used_ids(_)) -> Res=[H|ET], extract_imp_info1(T,ET)
807 ; extract_imp_info1(T,Res)
808 ).
809
810 % extract and merge important info and try to merge used_ids from two info lists
811 merge_imp_info2(Info1,Info2,ResInfos) :-
812 extract_imp_info1(Info1,I1),
813 extract_imp_info1(Info2,I2),
814 merge_aux(I1,I2,ResInfos).
815
816 merge_aux([],I2,Res) :- !, delete(I2,used_ids(_),Res). % used_ids not valid for new construct
817 merge_aux(I1,[],Res) :- !, delete(I1,used_ids(_),Res). % ditto
818 merge_aux(I1,I2,ResInfos) :-
819 ? (select(used_ids(Ids1),I1,II1)
820 ? -> (select(used_ids(Ids2),I2,II2)
821 -> ord_union(Ids1,Ids2,Ids3),
822 append(II1,[used_ids(Ids3)|II2],II)
823 ; append(II1,I2,II)
824 )
825 ; delete(I2,used_ids(_),II2),
826 append(I1,II2,II)
827 ),
828 sort(II,ResInfos). % TO DO: sort sublists ? and use ord_union?
829
830 important_info(contains_wd_condition).
831 important_info(prob_annotation(_)).
832 important_info(allow_to_lift_exists).
833 important_info(removed_typing).
834 %important_info(lambda_result(_)). % should probably not be copied
835
836 % variation of above which does not extract and merge used_ids:
837 extract_just_important_info_aux([],Acc,Acc).
838 extract_just_important_info_aux([H|T],Acc,Res) :-
839 (important_info(H), \+ member(H,Acc) -> extract_just_important_info_aux(T,[H|Acc],Res)
840 ; extract_just_important_info_aux(T,Acc,Res)).
841
842
843 is_a_conjunct(b(conjunct(A,B),pred,_),A,B).
844 % use is_a_conjunct_without_label if you want to avoid decomposing conjunction associated with a single label
845 is_a_conjunct_without_label(b(conjunct(A,B),pred,I),A,B) :- \+ get_info_labels(I,_).
846 % use decompose conjunct if you want to propagate labels down to the conjuncts
847 decompose_conjunct(b(conjunct(A,B),pred,I),ResA,ResB) :-
848 (get_info_labels(I,Labels)
849 -> add_labels_to_texpr(A,Labels,ResA), add_labels_to_texpr(B,Labels,ResB)
850 ; ResA=A, ResB=B).
851
852 size_of_conjunction(C,Size) :- size_of_conjunction(C,0,Size).
853 size_of_conjunction(C,Acc,Res) :- is_a_conjunct(C,A,B),!,
854 size_of_conjunction(B,Acc,A1),
855 size_of_conjunction(A,A1,Res).
856 size_of_conjunction(_,Acc,Size) :- Size is Acc+1.
857
858 conjunction_to_list(C,L) :- var(C),!,
859 add_error_fail(conjunction_to_list,'Internal error: var :',conjunction_to_list(C,L)).
860 conjunction_to_list(C,List) :-
861 conjunction_to_list2(C,List,[]).
862 conjunction_to_list2(X,I,O) :- X=b(E,_,_),
863 (E=conjunct(LHS,RHS) -> conjunction_to_list2(LHS,I,Inter),
864 conjunction_to_list2(RHS,Inter,O)
865 ; E = truth -> I=O
866 ; I = [X|O]).
867
868 % a variation of conjunction_to_list which propagates Rodin and pragma label infos down
869 % important for proof info; maybe we should only propagate Rodin labels ?
870 conjunction_to_list_with_rodin_labels(C,L) :- var(C),!,
871 add_error_fail(conjunction_to_list,'Internal error: var :',conjunction_to_list_with_rodin_labels(C,L)).
872 conjunction_to_list_with_rodin_labels(C,List) :-
873 conjunction_to_list_with_labels2(C,List,[]).
874 conjunction_to_list_with_labels2(b(conjunct(A,B),pred,Infos),I,O) :- !,
875 copy_rodin_label(Infos,A,B,LHS,RHS),
876 conjunction_to_list_with_labels2(LHS,I,Inter),
877 conjunction_to_list_with_labels2(RHS,Inter,O).
878 conjunction_to_list_with_labels2(X,I,O) :- X=b(E,_,_),
879 ( E = truth -> I=O
880 ; I = [X|O]).
881
882
883 copy_rodin_label(Infos,A,B,NewA,NewB) :- member(Pos,Infos), is_rodin_label_info(Pos),!,
884 add_rodin_label_info(A,Pos,NewA),
885 add_rodin_label_info(B,Pos,NewB).
886 copy_rodin_label(_,A,B,A,B).
887
888 add_rodin_label_info(b(E,T,I),Pos,b(E,T,I2)) :-
889 (member(Pos,I), is_rodin_label_info(Pos) -> I2=I
890 ; I2 = [Pos|I]).
891
892 is_rodin_label_info(nodeid(Pos)) :- functor(Pos,rodinpos,_).
893
894
895 flatten_conjunctions(List,FlattenedList) :- flatten_conj_aux(List,FlattenedList,[]).
896 flatten_conj_aux([]) --> !, [].
897 flatten_conj_aux([H|T]) --> !, flatten_conj_aux(H),flatten_conj_aux(T).
898 flatten_conj_aux(C) --> {is_a_conjunct(C,LHS,RHS)},
899 !,
900 flatten_conj_aux(LHS), flatten_conj_aux(RHS).
901 flatten_conj_aux(Truth) --> {is_truth(Truth)},!,[].
902 flatten_conj_aux(C) --> [C].
903
904 member_in_conjunction(M,Conj) :- is_a_conjunct(Conj,LHS,RHS),!,
905 ? (member_in_conjunction(M,LHS) ; member_in_conjunction(M,RHS)).
906 member_in_conjunction(M,M).
907
908 % a version of member_in_conjunction which can deal with lazy_let_pred :
909 % member_in_conjunction_cse(FullConjunctWithLets,InnerConjunctNotALet, Conjunction)
910 member_in_conjunction_cse(M,InnerConj,Conj) :- is_a_conjunct(Conj,LHS,RHS),!,
911 (member_in_conjunction_cse(M,InnerConj,LHS) ; member_in_conjunction_cse(M,InnerConj,RHS)).
912 member_in_conjunction_cse(Conj,InnerConj,b(lazy_let_pred(ID,Share,Body),pred,Info)) :-
913 Conj = b(lazy_let_pred(ID,Share,BConj),pred,Info),!,
914 member_in_conjunction_cse(BConj,InnerConj,Body).
915 member_in_conjunction_cse(M,M,M).
916
917 % not terribly efficient way to select and remove a conjunct from a predicate
918 select_member_in_conjunction(M,Conj,Rest) :- is_a_conjunct(Conj,LHS,RHS),!,
919 (select_member_in_conjunction(M,LHS,RL), conjunct_predicates([RL,RHS],Rest)
920 ; select_member_in_conjunction(M,RHS,RR), conjunct_predicates([LHS,RR],Rest)).
921 select_member_in_conjunction(M,M,b(truth,pred,[])).
922
923 is_a_disjunct(b(disjunct(A,B),pred,_),A,B).
924 is_a_negation(b(negation(A),pred,_),A).
925
926 disjunction_to_list(C,L) :- var(C),!,
927 add_error_fail(disjunction_to_list,'Internal error: var :',disjunction_to_list(C,L)).
928 disjunction_to_list(C,List) :-
929 disjunction_to_list2(C,List,[]).
930 disjunction_to_list2(C,I,O) :- is_a_disjunct(C,LHS,RHS),!,
931 disjunction_to_list2(LHS,I,Inter),
932 disjunction_to_list2(RHS,Inter,O).
933 disjunction_to_list2(X,[X|R],R).
934
935 is_an_implication(b(implication(A,B),pred,_),A,B).
936
937 is_an_equivalence(b(equivalence(A,B),pred,_),A,B).
938
939
940 is_a_disjunct_or_implication(b(DI,pred,_),Type,A,B) :- is_a_disj_or_impl_aux(DI,Type,A,B).
941 is_a_disj_or_impl_aux(disjunct(A,B),'disjunction',A,B).
942 is_a_disj_or_impl_aux(implication(A,B),'implication',NA,B) :-
943 create_negation(A,NA).
944 is_a_disj_or_impl_aux(negation(b(conjunct(A,B),pred,_)),'negated conjunction',NA,NB) :-
945 create_negation(A,NA),create_negation(B,NB).
946
947 % a more liberal version of is_a_conjunct/2 which also detects negated disjunctions/implications
948 is_a_conjunct_or_neg_disj(b(DI,pred,I),A,B) :- is_conjunct_aux(DI,I,A,B).
949
950 is_conjunct_aux(conjunct(LHS,RHS),_,LHS,RHS).
951 is_conjunct_aux(negation(DISJ),_,NegLHS,NegRHS) :-
952 is_a_disjunct_or_implication(DISJ,_Type,LHS,RHS),
953 create_negation(LHS,NegLHS),
954 create_negation(RHS,NegRHS).
955 is_conjunct_aux(equal(TA,TB),I,b(equal(TA1,TB1),pred,I),b(equal(TA2,TB2),pred,I)) :-
956 % split TA1|->TA2 = TB1|->TB2, cf, split_equality/3; useful for enumeration order analysis
957 get_texpr_couple(TA,TA1,TA2),
958 get_texpr_couple(TB,TB1,TB2).
959 % print('Splitting equality in is_a_conjunct_or_neg_disj: '), translate:print_bexpr(b(equal(TA,TB),pred,I)),nl.
960
961 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
962 % remove all info fields by fresh variables
963 % typically the result will be unified with AST terms which contain full info fields
964 remove_all_infos(TExpr,TNExpr) :-
965 var(TExpr),!,TExpr=TNExpr.
966 % in contrast to remove_all_infos_and_ground we provide no special treatment of values with closures here;
967 % there could be a problem if we unify with a free variable as value
968 remove_all_infos(TExpr,TNExpr) :-
969 get_texpr_expr(TExpr,Expr),
970 get_texpr_type(TExpr,Type),
971 syntaxtransformation(Expr,Subs,_,NSubs,NExpr),
972 create_texpr(NExpr,Type,_,TNExpr),
973 maplist(remove_all_infos,Subs,NSubs).
974
975 % replace all info fields
976 remove_all_infos_and_ground(TExpr,TNExpr) :-
977 var(TExpr),!,TExpr=TNExpr.
978 remove_all_infos_and_ground(b(value(Value),Type,_),TNExpr) :-
979 % special case for closure(_,_,_) since it is not covered by syntraxtransformation/5
980 % most useful for intervals
981 !,
982 remove_all_infos_from_bvalue(Value,NValue),
983 TNExpr = b(value(NValue),Type,[]).
984 remove_all_infos_and_ground(TExpr,TNExpr) :-
985 get_texpr_expr(TExpr,Expr),
986 get_texpr_type(TExpr,Type),
987 syntaxtransformation(Expr,Subs,_,NSubs,NExpr),
988 create_texpr(NExpr,Type,[],TNExpr),
989 maplist(remove_all_infos_and_ground,Subs,NSubs).
990
991 remove_all_infos_from_bvalue(Var,Res) :- var(Var),!, Res=Var.
992 remove_all_infos_from_bvalue((A,B),(RA,RB)) :- !,
993 remove_all_infos_from_bvalue(A,RA),
994 remove_all_infos_from_bvalue(B,RB).
995 remove_all_infos_from_bvalue(closure(P,T,Body),Res) :- !,
996 remove_all_infos_and_ground(Body,RBody),
997 Res = closure(P,T,RBody).
998 % TODO: we could provide more cases like records, sets as lists, freetype values
999 remove_all_infos_from_bvalue(Val,Val).
1000
1001 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1002
1003 % a version of create_exists_opt which also detects top-level disjunctions
1004 % and marks the exists as generated and as allow_to_lift_exists
1005 create_exists_opt_liftable(Ids,b(disjunct(A,B),pred,Info1),NewPred) :- !,
1006 create_exists_opt_liftable(Ids,A,PA),
1007 create_exists_opt_liftable(Ids,B,PB),
1008 disjunct_predicates_with_pos_info(PA,PB,b(NP,pred,Info2)),
1009 NewPred=b(NP,pred,NewInfo),
1010 extract_just_important_info_aux(Info1,Info2,NewInfo). % copy symbolic or other relevant info
1011 create_exists_opt_liftable(Ids,Pred,NewPred) :- conjunction_to_list(Pred,L),
1012 create_exists_opt(Ids,L,[allow_to_lift_exists],NewPred,_Modified).
1013
1014 % create_exists_opt(TIds,Preds,NewPred)
1015 % creating an existential quantification with some optimisations.
1016 % TIds: The typed identifiers that are quantified
1017 % Preds: A list of predicates
1018 % NewPred: The (optimised) quantified expression
1019 % Basically two optimisations are performed:
1020 % - identifiers that are not used at all are removed from the quantifier
1021 % - predicates that do not use one of the quantified identifiers are moved
1022 % outside the quantification, resulting in a predicate of the form "P & #x.Q(x)"
1023
1024 create_exists_opt(TIds,Preds,NewPred) :-
1025 create_exists_opt(TIds,Preds,[],NewPred,_).
1026
1027 create_exists_opt(TIds,Preds,NewPred,Modified) :-
1028 create_exists_opt(TIds,Preds,[],NewPred,Modified).
1029
1030 create_exists_opt([],Preds,_,NewPred,Modified) :- !, Modified = false,
1031 conjunct_predicates(Preds,NewPred).
1032 create_exists_opt(TIds,Preds,AdditionalInfos,Res,Mod) :-
1033 get_texpr_ids(TIds,UnsortedIds), sort(UnsortedIds,Ids),
1034 (create_exists_opt1(TIds,Ids,Preds,AdditionalInfos,NewPred2,Modified) -> Res = NewPred2, Mod=Modified
1035 ; add_internal_error('Call failed:',create_exists_opt(TIds,Preds,AdditionalInfos,_,_)),fail).
1036 %create_exists_opt1(TIds,_,Preds,AdditionalInfos,NewPred,Modified) :- preference(data_validation_mode,true),
1037 % % do not lift predicates outside of existential quantifiers and change order; see rule_avec_DV.mch ClearSy example (N_ITERa_avec_DV_sans_DV) and test 1945
1038 create_exists_opt1(TIds,Ids,Preds,AdditionalInfos,NewPred2,Modified) :-
1039 create_exists_opt2(Preds,first,Ids,[],Inner,Outer,UsedIds),
1040 % Inner: quantified part, Outer: part which does not have to be quantified
1041 ( Inner = [] -> AllPreds=Outer % no exists needed
1042 ; % Inner = [_|_] ->
1043 create_filtered_exists(TIds,UsedIds,Inner,AdditionalInfos,Exists,IModified),
1044 append(Outer,[Exists],AllPreds)
1045 ),
1046 (Outer=[_|_] -> Modified=true % TO DO: check if TIds=UsedTIds
1047 ; IModified==true -> Modified=true
1048 ; UsedIds == Ids -> Modified= false
1049 ; Modified=true),
1050 conjunct_predicates(AllPreds,NewPred2).
1051
1052 % create an exists for the used Ids only
1053 create_filtered_exists(TIds,UsedIds,Inner,AdditionalInfos,Exists,_) :-
1054 ceo_filter_used_ids(TIds,UsedIds,UsedTIds), % filter out unused variables
1055 conjunct_predicates_with_pos_info(Inner,I), % we could store used_ids info
1056 create_exists_detect_tautology_aux(UsedTIds,I,AdditionalInfos,Exists).
1057 % remove_typing also added in create_exists_detect_tautology_aux
1058
1059
1060 % return Inner: predicates inside quantifier and Outer: predicates that can be moved out of the quantifier
1061 create_exists_opt2([],_,_Ids,UsedIds,[],[],UsedIds) :- !.
1062 create_exists_opt2([Pred|Prest],First,Ids,UsedIdsIn,Inner,Outer,UsedIdsOut) :- !,
1063 find_identifier_uses_if_necessary(Pred, [], LocalUses), % TODO: add used_ids(LocalUses) to Pred
1064 ord_intersection(Ids,LocalUses,ExistsIdsUsed),
1065 ( ExistsIdsUsed = [], % Pred uses none of the quantified ids: we can move it out
1066 (First==first -> true
1067 ; preference(data_validation_mode,false), % see test 1945; step 39 in trace replay
1068 always_well_defined_or_disprover_mode(Pred) % TODO: we should probably also check this !
1069 )
1070 ->
1071 Inner = Irest,
1072 Outer = [Pred|Orest], % move Pred out of existential quantifier as it does not depend on quantified variables
1073 % format('MOVED out of #(~w): ',[Ids]),translate:print_bexpr(Pred), format(' Uses ~w [~w]~n',[LocalUses,ExistsIdsUsed]),
1074 create_exists_opt2(Prest,first,Ids,UsedIdsIn,Irest,Orest,UsedIdsOut)
1075 ;
1076 update_used_ids(Pred,LocalUses,Pred2),
1077 Inner = [Pred2|Irest],
1078 Outer = Orest,
1079 ord_union(UsedIdsIn,ExistsIdsUsed,Urest),
1080 create_exists_opt2(Prest,not_first_anymore,Ids,Urest,Irest,Orest,UsedIdsOut)
1081 ).
1082 create_exists_opt2(Pred,First,Ids,UsedIdsIn,Inner,Outer,UsedIdsOut) :-
1083 add_error(create_exists_opt,'Expecting predicate list: ',Pred),
1084 create_exists_opt2([Pred],First,Ids,UsedIdsIn,Inner,Outer,UsedIdsOut).
1085
1086 % construct exists optimized: keep only used TIds
1087 ceo_filter_used_ids([],_UsedIds,[]).
1088 ceo_filter_used_ids([TId|Irest],UsedIds,Filtered) :-
1089 get_texpr_id(TId,Id),
1090 ( ord_member(Id,UsedIds) -> Filtered = [TId|Frest] % id used: keep it
1091 ; Filtered = Frest),
1092 ceo_filter_used_ids(Irest,UsedIds,Frest).
1093
1094 % a version of create_exists which also detects x=E and x:E, x>E, not(x>E) tautologies
1095 % we could replace this by a more generic prover
1096 create_exists_detect_tautology_aux([TID],b(member(LHS,RHS),pred,_),_,Truth) :-
1097 get_texpr_id(LHS,ID), get_texpr_id(TID,ID),
1098 definitely_not_empty_set(RHS),
1099 always_well_defined_or_disprover_mode(RHS),
1100 !, % replace #x.(x:RHS) by TRUTH
1101 debug_format(19,'Detected tautology exists membership over ~w~n',[ID]),
1102 Truth=b(truth,pred,[]).
1103 create_exists_detect_tautology_aux([TID],b(Pred,_,_),_,Truth) :-
1104 is_comparison(Pred,pos_neg(pos,TID),L,R), get_texpr_id(TID,ID),
1105 ((LHS,RHS)=(L,R) ; (LHS,RHS)=(R,L)),
1106 get_texpr_id(LHS,ID),
1107 \+ occurs_in_expr(ID,RHS),
1108 always_well_defined_or_disprover_mode(RHS),
1109 !, % replace #x.(x COMP E) by TRUTH
1110 debug_format(19,'Detected tautology comparison over ~w~n',[ID]),
1111 Truth=b(truth,pred,[]).
1112 %create_exists_detect_tautology_aux(Ids,b(disjunct(A,B),pred,Info1),AdditionalInfos,NewPred) :- !,
1113 % create_exists(Ids,A,PA), create_exists(Ids,B,PB),
1114 % disjunct_predicates_with_pos_info(PA,PB,b(NP,pred,Info2)),
1115 % NewPred=b(NP,pred,NewInfo),
1116 % extract_just_important_info_aux(Info1,Info2,NewInfo). % copy symbolic or other relevant info
1117 create_exists_detect_tautology_aux(Ids,Pred,AdditionalInfos,NewPred2) :-
1118 create_exists_or_let_predicate(Ids,Pred,NewPred),
1119 add_texpr_infos_if_new(NewPred,[removed_typing|AdditionalInfos],NewPred2).
1120 % removed_typing to avoid spurious exists_body_warning, see test 1681, 625
1121
1122
1123 is_eventb_comprehension_set(b(comprehension_set(TopIds,Body),_,Info),Ids,PRED,EXPR) :-
1124 is_eventb_comprehension_set(TopIds,Body,Info,Ids,PRED,EXPR).
1125 is_eventb_comprehension_set([TID1],Body,Info,Ids,PRED,EXPR) :-
1126 Body = b(exists(Ids,InnerBody),pred,_),
1127 conjunction_to_list(InnerBody,Inner),
1128 append(Inner1,[b(equal(TID2,EXPR),pred,EqInfo)],Inner),
1129 (member(was(event_b_comprehension_set),Info) -> true ;
1130 member(prob_annotation('LAMBDA-EQUALITY'),EqInfo) % relevant for TLA2B
1131 ),
1132 same_id(TID1,TID2,_),
1133 conjunct_predicates(Inner1,PRED),
1134 % we check that TID1 is not being used in P1 and not just rely on was(event_b_comprehension_set)
1135 not_occurs_in_expr(PRED,TID1).
1136
1137 % -------------------
1138
1139 is_equal(b(equal(LHS,RHS),pred,_),A,B) :-
1140 ((A,B)=(LHS,RHS) ; (A,B)=(RHS,LHS)).
1141
1142 :- use_module(typing_tools,[type_has_at_least_two_elements/1]).
1143 is_comparison(greater(A,B),_,A,B).
1144 is_comparison(less(A,B),_,A,B).
1145 is_comparison(greater_equal(A,B),_,A,B).
1146 is_comparison(less_equal(A,B),_,A,B).
1147 is_comparison(equal(A,B),pos_neg(P,TID),A,B) :-
1148 % for neg: we need to make sure there is more than one value in the type (otherwise we cannot make equal false)
1149 % for pos: assuming the RHS expression above is well-defined there must be at least one element; no need to check non_empty_type(Type)
1150 (P=pos -> true ; get_texpr_type(TID,Type),type_has_at_least_two_elements(Type)).
1151 is_comparison(not_equal(A,B),pos_neg(P,TID),A,B) :- % ditto but with pos and neg reversed
1152 (P=neg -> true ; get_texpr_type(TID,Type),type_has_at_least_two_elements(Type)).
1153 is_comparison(negation(b(Comp,pred,_)),PosNeg,A,B) :- negate(PosNeg,P2),
1154 is_comparison(Comp,P2,A,B).
1155 negate(pos_neg(pos,T),pos_neg(neg,T)).
1156 negate(pos_neg(neg,T),pos_neg(pos,T)).
1157
1158
1159
1160 % is true if a predicate Pred can be split into two parts:
1161 % Outer which does not depend on LocalIds (can be lifted out) and Inner which does
1162 detect_global_predicates(LocalIds,Pred,Outer,Inner) :-
1163 get_texpr_ids(LocalIds,UnsortedIds), sort(UnsortedIds,Ids),
1164 conjunction_to_list(Pred,Preds),
1165 split_predicate_local_global(Preds,Ids,OuterL,InnerL),
1166 OuterL \= [],
1167 conjunct_predicates(OuterL,Outer),
1168 conjunct_predicates(InnerL,Inner).
1169 split_predicate_local_global([],_Ids,[],[]).
1170 split_predicate_local_global([P|Ps],Ids,Outer,Inner) :-
1171 (is_local_predicate(Ids,P)
1172 -> Inner = [P|Is], split_predicate_local_global(Ps,Ids,Outer,Is)
1173 ; Outer = [P|Os], split_predicate_local_global(Ps,Ids,Os,Inner)).
1174 is_local_predicate(Ids,Pred) :-
1175 find_identifier_uses_if_necessary(Pred, [], LocalUses),
1176 ord_intersect(Ids,LocalUses).
1177
1178 %:- use_module(b_global_sets,[b_global_set/1]).
1179 definitely_not_empty_set(b(SET,T,_)) :- not_empty_set_aux(SET,T).
1180 not_empty_set_aux(bool_set,_).
1181 not_empty_set_aux(integer_set(_),_).
1182 not_empty_set_aux(float_set,_).
1183 not_empty_set_aux(real_set,_).
1184 not_empty_set_aux(string_set,_).
1185 not_empty_set_aux(set_extension(X),_) :- dif(X,[]).
1186 not_empty_set_aux(sequence_extension(X),_) :- dif(X,[]).
1187 not_empty_set_aux(pow_subset(_),_). % always contains at least the empty set
1188 not_empty_set_aux(fin_subset(_),_). % ditto
1189 not_empty_set_aux(seq(_),_). % ditto
1190 not_empty_set_aux(seq1(_),_). % ditto
1191 not_empty_set_aux(pow1_subset(A),_) :- definitely_not_empty_set(A).
1192 not_empty_set_aux(fin1_subset(A),_) :- definitely_not_empty_set(A).
1193 not_empty_set_aux(seq1(A),_) :- definitely_not_empty_set(A).
1194 not_empty_set_aux(iseq1(A),_) :- definitely_not_empty_set(A).
1195 not_empty_set_aux(cartesian_product(A,B),_) :- definitely_not_empty_set(A), definitely_not_empty_set(B).
1196 not_empty_set_aux(partial_function(_A,_B),_). % always contains at least the empty set
1197 not_empty_set_aux(partial_injection(_A,_B),_). % ditto
1198 not_empty_set_aux(relations(_A,_B),_). % ditto
1199 not_empty_set_aux(total_function(A,B),_) :-
1200 (definitely_not_empty_set(B) -> true
1201 ; definitely_empty_set(A)). % if A is empty, then the set of total functions is {{}}
1202 % TODO: add a few more function rules
1203 not_empty_set_aux(value(S),_) :- not_empty_value(S).
1204
1205 %not_empty_set_aux(identifier(X),set(global(X))) :- bmachine:b_get_machine_set(X). % what if we have a local variable ? ENSURE THAT WE DO NOT ALLOW identifier X to stand for global set X; see ExistentialGlobalSetIDTest in Tester % also: b_global_set not yet computed when ast_cleanup runs on startup !
1206 % TO DO: determine which identifier(X) refer to global set names
1207 not_empty_set_aux(interval(A,B),_) :- get_integer(A,IA), get_integer(B,IB), IA =< IB.
1208
1209 :- use_module(b_global_sets,[b_non_empty_global_set/1]).
1210 not_empty_value(S) :- var(S),!,fail.
1211 not_empty_value(avl_set(_)).
1212 not_empty_value([_|_]).
1213 not_empty_value(global_set(G)) :- b_non_empty_global_set(G). % always true
1214 %TODO: closure?
1215
1216 definitely_empty_set(b(ES,_,_)) :- is_empty_set_aux(ES).
1217 is_empty_set_aux(empty_set).
1218 is_empty_set_aux(empty_sequence).
1219 is_empty_set_aux(domain(D)) :- definitely_empty_set(D).
1220 is_empty_set_aux(range(D)) :- definitely_empty_set(D).
1221 is_empty_set_aux(domain_subtraction(_,Rel)) :- definitely_empty_set(Rel).
1222 is_empty_set_aux(domain_restriction(Dom,Rel)) :- (definitely_empty_set(Dom) -> true ; definitely_empty_set(Rel)).
1223 is_empty_set_aux(range_restriction(Rel,Ran)) :- (definitely_empty_set(Ran) -> true ; definitely_empty_set(Rel)).
1224 is_empty_set_aux(range_subtraction(Rel,_)) :- definitely_empty_set(Rel).
1225 is_empty_set_aux(interval(A,B)) :- get_integer(A,IA), get_integer(B,IB), IA > IB.
1226 is_empty_set_aux(intersection(A,B)) :- (definitely_empty_set(A) -> true ; definitely_empty_set(B)).
1227 is_empty_set_aux(value(V)) :- V==[].
1228
1229
1230 get_integer(b(B,_,_),I) :- get_integer_aux(B,I).
1231 get_integer_aux(integer(I),I).
1232 get_integer_aux(value(V),I) :- get_integer_value(V,I).
1233 get_integer_value(V,I) :- nonvar(V),V=int(I), integer(I).
1234
1235
1236
1237 :- use_module(probsrc(custom_explicit_sets),[avl_is_interval/3]).
1238 get_interval(b(I,set(integer),_),Low,Up) :-
1239 is_interval_aux(I,Low,Up).
1240 is_interval_aux(interval(Low,Up),Low,Up).
1241 is_interval_aux(value(CS),Low,Up) :- nonvar(CS), CS=avl_set(AVL), % occurs in Leftpad_i.imp
1242 Low = b(integer(LI),integer,[]), Up = b(integer(UI),integer,[]),
1243 avl_is_interval(AVL,LI,UI).
1244 is_interval_aux(set_extension(List),Low,Up) :- print(l(List)),nl,
1245 sort(List,SList),
1246 SList = [Low|Rest], get_integer(Low,LI),
1247 last(SList,Up), get_integer(Up,UI),
1248 length(List,Len),
1249 Len is UI-LI+1,
1250 maplist(get_integer,Rest,_).
1251
1252 % a simple let-detection
1253 create_exists_or_let_predicate([H|T],b(conjunct(LHS,RHS),pred,I),NewPred) :- get_texpr_id(H,ID),
1254 ? is_equal(LHS,TID,IDEXPR), % TO DO: should we do a more complicated check here ? exist technique useful for SLOT-24 codespeed test
1255 get_texpr_id(TID,ID), \+ occurs_in_expr(ID,IDEXPR),
1256 maplist(not_occurs_in_expr(IDEXPR),T),
1257 !,
1258 NewPred = b(let_predicate([TID],[IDEXPR],Body),pred,I),
1259 %print('LET: '),translate:print_bexpr(NewPred),nl,
1260 create_exists_or_let_predicate(T,RHS,Body).
1261 create_exists_or_let_predicate(Ids,Pred,NewPred) :- create_exists(Ids,Pred,NewPred).
1262
1263 not_occurs_in_expr(IDEXPR,TID) :- get_texpr_id(TID,ID), \+ occurs_in_expr(ID,IDEXPR).
1264
1265 create_exists([],Pred,NewPred) :- !,Pred=NewPred.
1266 create_exists(Ids,Pred,NewPred) :-
1267 find_identifier_uses_for_quantifier_body(Ids,Pred, Used),
1268 extract_info_wo_used_ids(Pred,NewImportantInfo),
1269 create_texpr(exists(Ids,Pred),pred,[used_ids(Used)|NewImportantInfo],NewPred).
1270
1271 % a version of create_exists which can merge with an already present exists if possible
1272 % possibly more expensive as identfiers used are recomputed for the moment (TODO: reuse used_ids and subtract)
1273 create_or_merge_exists(IDs, Condition, Exists):-
1274 get_texpr_expr(Condition,exists(InnerVars,InnerCond)),!,
1275 % fuse two exists together
1276 append(IDs,InnerVars,Vars),
1277 create_or_merge_exists(Vars,InnerCond,Exists).
1278 create_or_merge_exists(IDs, Condition, Exists):-
1279 create_exists(IDs,Condition,Exists).
1280
1281
1282 create_forall([],Pred,NewPred) :- !,Pred=NewPred.
1283 create_forall(Ids,Pred,NewPred) :-
1284 find_identifier_uses_for_quantifier_body(Ids,Pred, Used),
1285 split_forall_body(Pred,LHS,RHS),
1286 extract_info_wo_used_ids_and_pos(LHS,RHS,NewImportantInfo),
1287 create_texpr(forall(Ids,LHS,RHS),pred,[used_ids(Used)|NewImportantInfo],NewPred).
1288 split_forall_body(b(implication(LHS,RHS),_,_),LHS,RHS) :- !.
1289 split_forall_body(RHS,b(truth,pred,[]),RHS).
1290
1291 create_implication(b(truth,pred,_),P,Res) :- !, Res=P.
1292 create_implication(b(falsity,pred,_),P,Res) :- !, create_negation(P,Res).
1293 create_implication(Lhs,Rhs,b(implication(Lhs,Rhs),pred,NewInfo)) :-
1294 extract_info(Lhs,Rhs,NewInfo).
1295
1296 create_equivalence(Lhs,Rhs, b(equivalence(Lhs,Rhs),pred,NewInfo)) :-
1297 extract_info(Lhs,Rhs,NewInfo).
1298
1299 create_negation(b(P,pred,I),Res) :- create_negation_aux(P,I,R),!,Res=R.
1300 create_negation(Pred,b(negation(Pred),pred,NewInfo)) :-
1301 extract_info(Pred,Infos),
1302 (get_texpr_non_label_posinfo(Pred,Pos) -> NewInfo = [Pos|Infos] ; NewInfo=Infos).
1303
1304 create_negation_aux(truth,I,R) :- !, R=b(falsity,pred,I).
1305 create_negation_aux(falsity,I,R) :- !, R=b(truth,pred,I).
1306 create_negation_aux(negation(Pred),_,R) :- R=Pred. % not(not(P)) = P
1307 %create_negation_aux(equal(A,B),I,R) :- !, R=b(not_equal(A,B),pred,I).
1308 %create_negation_aux(not_equal(A,B),I,R) :- !, R=b(equal(A,B),pred,I).
1309 % we could add some rules about negating member <-> not_member, ... but be careful with effects on is_negation_of
1310
1311 % check if something is the negation of something else (quite stupid at the moment)
1312 % used, e.g., to detect IF-THEN-ELSE constructs in b_ast_cleanup
1313 is_negation_of(P,NP) :-
1314 create_negation(P,NotP), % works both with not(A),A or A,not(A)
1315 same_texpr(NotP,NP).
1316 is_negation_of(b(P,pred,_),b(NP,pred,_)) :- is_negation_aux(P,NP).
1317
1318 is_negation_aux(equal(A,B),NP) :- is_negation_of_equality(NP,A,B).
1319 is_negation_aux(not_equal(A,B),NP) :- is_negation_of_disequality(NP,A,B).
1320 is_negation_aux(subset(XA,SA),not_subset(XB,SB)) :- same_texpr(XA,XB), same_texpr(SA,SB).
1321 is_negation_aux(not_subset(XA,SA),subset(XB,SB)) :- same_texpr(XA,XB), same_texpr(SA,SB).
1322 is_negation_aux(subset_strict(XA,SA),not_subset_strict(XB,SB)) :- same_texpr(XA,XB), same_texpr(SA,SB).
1323 is_negation_aux(not_subset_strict(XA,SA),subset_strict(XB,SB)) :- same_texpr(XA,XB), same_texpr(SA,SB).
1324 is_negation_aux(member(XA,SA),not_member(XB,SB)) :- same_texpr(XA,XB), same_texpr(SA,SB).
1325 is_negation_aux(not_member(XA,SA),member(XB,SB)) :- same_texpr(XA,XB), same_texpr(SA,SB).
1326 is_negation_aux(less(A,B),greater_equal(AA,BB)) :- same_texpr(A,AA), same_texpr(B,BB).
1327 is_negation_aux(less(A,B),less_equal(BB,AA)) :- same_texpr(A,AA), same_texpr(B,BB).
1328 is_negation_aux(less_equal(B,A),less(AA,BB)) :- same_texpr(A,AA), same_texpr(B,BB).
1329 is_negation_aux(less_equal(A,B),greater(AA,BB)) :- same_texpr(A,AA), same_texpr(B,BB).
1330 is_negation_aux(greater_equal(A,B),NP) :- is_negation_aux(less_equal(B,A),NP).
1331 is_negation_aux(greater(A,B),NP) :- is_negation_aux(less(B,A),NP).
1332 is_negation_aux(less_equal_real(B,A),less_real(AA,BB)) :- same_texpr(A,AA), same_texpr(B,BB).
1333 is_negation_aux(less_real(B,A),less_equal_real(AA,BB)) :- same_texpr(A,AA), same_texpr(B,BB).
1334 is_negation_aux(negation(A),negation(B)) :- is_negation_of(A,B).
1335 is_negation_aux(truth,falsity).
1336 is_negation_aux(falsity,truth).
1337 % TO DO: detect more ?? x < y <=> not ( x > y-1 )
1338
1339 is_negation_of_equality(not_equal(AA,BB),A,B) :- same_texpr(A,AA), same_texpr(B,BB).
1340 is_negation_of_equality(equal(AA,BB),A,B) :- same_texpr(A,AA), neg_value(BB,B).
1341
1342 neg_value(b(boolean_true,_,_),b(boolean_false,_,_)).
1343 neg_value(b(boolean_false,_,_),b(boolean_true,_,_)).
1344
1345 is_negation_of_disequality(equal(AA,BB),A,B) :- same_texpr(A,AA), same_texpr(B,BB).
1346 is_negation_of_disequality(not_equal(AA,BB),A,B) :- same_texpr(A,AA), neg_value(BB,B).
1347
1348
1349 % another version which is simpler can can be used to get the negation of some operators
1350
1351 get_negated_operator_expr(b(E,pred,_),Res) :- negate_expr_aux(E,Res).
1352 negate_expr_aux(falsity,truth).
1353 negate_expr_aux(truth,falsity).
1354 negate_expr_aux(member(X,S),not_member(X,S)).
1355 negate_expr_aux(not_member(X,S),member(X,S)).
1356 negate_expr_aux(subset(X,S),not_subset(X,S)).
1357 negate_expr_aux(not_subset(X,S),subset(X,S)).
1358 negate_expr_aux(subset_strict(X,S),not_subset_strict(X,S)).
1359 negate_expr_aux(not_subset_strict(X,S),subset_strict(X,S)).
1360 negate_expr_aux(equal(X,S),not_equal(X,S)).
1361 negate_expr_aux(not_equal(X,S),equal(X,S)).
1362 negate_expr_aux(less(X,S),greater_equal(X,S)).
1363 negate_expr_aux(greater_equal(X,S),less(X,S)).
1364 negate_expr_aux(less_equal(X,S),greater(X,S)).
1365 negate_expr_aux(greater(X,S),less_equal(X,S)).
1366 negate_expr_aux(less_equal_real(X,S),less_real(S,X)).
1367 negate_expr_aux(less_real(X,S),less_equal_real(S,X)).
1368 % TO DO: negation()
1369
1370
1371 % a liberal version for finding equalities
1372 is_equality(TP,TA,TB) :- get_texpr_expr(TP,P), is_equality_aux(P,TA,TB).
1373
1374 is_equality_aux(Var,TA,TB) :- var(Var),!, add_internal_error('Illegal call: ', is_equality_aux(Var,TA,TB)),fail.
1375 is_equality_aux(equal(TA,TB),TA,TB).
1376 is_equality_aux(not_equal(TA,TB),NTA,NTB) :-
1377 (negate_boolean_value(TB,NTB) -> NTA=TA
1378 ; NTB=TB, negate_boolean_value(TA,NTA)). % TA /= TRUE ---> TA = FALSE
1379 is_equality_aux(partition(TA,[TB]),TA,TB).
1380 is_equality_aux(member(TA,TSet),TA,TB) :- singleton_set_extension(TSet,TB). % TA:{TB}
1381 is_equality_aux(negation(TExpr),TA,TB) :- get_negated_operator_expr(TExpr,NT), is_equality_aux(NT,TA,TB).
1382
1383 negate_boolean_value(b(B,T,I),b(NB,T,I)) :- neg_bool_aux(B,NB).
1384 neg_bool_aux(boolean_true,boolean_false).
1385 neg_bool_aux(boolean_false,boolean_true).
1386 % TODO: should we also detect value(pred_true), ....
1387
1388 singleton_set_extension(b(SONE,Type,_),El) :- singleton_set_extension_aux(SONE,Type,El).
1389 singleton_set_extension_aux(set_extension([El]),_,El).
1390 singleton_set_extension_aux(value(Set),set(Type),b(value(El),Type,[])) :- custom_explicit_sets:singleton_set(Set,El).
1391 singleton_set_extension_aux(sequence_extension([El]),_,Couple) :-
1392 ONE = b(integer(1),integer,[]),
1393 create_couple(ONE,El,Couple).
1394
1395
1396 % detect various forms of membership:
1397 is_membership(b(Expr,pred,_),TID,Set) :- is_membership_aux(Expr,TID,Set).
1398 is_membership_aux(member(TID,Set),TID,Set).
1399 is_membership_aux(subset(SONE,Set),TID,Set) :- singleton_set_extension(SONE,TID). % {TID} <: Set
1400
1401 % detect even more forms of membership:
1402 is_membership_or_equality(b(Expr,pred,_),TID,Set) :-
1403 (is_membership_aux(Expr,TID,Set) -> true ; is_mem_eq_aux(Expr,TID,Set)).
1404
1405 is_mem_eq_aux(equal(TID,VAL),TID,Set) :- % x=VAL <==> x:{VAL}
1406 get_texpr_type(VAL,Type),
1407 safe_create_texpr(set_extension([VAL]),set(Type),Set).
1408
1409 % extract a lambda equality from a body; we suppose the equality is the last conjunct
1410 get_lambda_equality(b(equal(TID,ResultExpr),pred,_),ID,[],ResultExpr) :- get_texpr_id(TID,ID).
1411 get_lambda_equality(b(conjunct(LHS,RHS),pred,_),ID,[LHS|T],ResultExpr) :-
1412 get_lambda_equality(RHS,ID,T,ResultExpr).
1413
1414 % ---------------------------------
1415
1416 is_pow_subset(B,Set) :-
1417 ( B = b(pow_subset(Set),_,_)
1418 ; B = b(fin_subset(Set),_,_),
1419 finite_wd_set_value(Set)
1420 ).
1421 is_pow1_subset(B,Set) :-
1422 ( B = b(pow1_subset(Set),_,_)
1423 ; B = b(fin1_subset(Set),_,_),
1424 finite_wd_set_value(Set)
1425 ).
1426
1427 % ---------------------------------
1428
1429 get_texpr_couple(b(couple(TA1,TA2),_,_),TA1,TA2).
1430
1431 % detect TA1|->TA2 = TB1|->TB2 and split into two
1432 split_equality(b(equal(TA,TB),pred,I),b(equal(TA1,TB1),pred,I),b(equal(TA2,TB2),pred,I)) :-
1433 get_texpr_couple(TA,TA1,TA2),
1434 get_texpr_couple(TB,TB1,TB2).
1435
1436 create_equality(b(_,TA,_),b(_,TB,_),_) :- TA \= TB, \+ unify_types_strict(TA,TB),!,
1437 add_internal_error('Creating equality with incompatible types:',equal(TA,TB)),fail.
1438 create_equality(A,B,Equality) :-
1439 safe_create_texpr(equal(A,B),pred,Equality).
1440
1441 create_couple(A,B,b(couple(A,B),couple(TA,TB),Infos)) :-
1442 get_texpr_type(A,TA), get_texpr_type(B,TB),
1443 extract_info(A,B,Infos).
1444
1445 % couplise_list for typed expression list
1446 create_couple([A],Couple) :- !,A=Couple.
1447 create_couple([A,B|Rest],Couple) :-
1448 create_couple(A,B,Couple1),
1449 create_couple([Couple1|Rest],Couple).
1450
1451 % derive typing from Ids
1452 create_comprehension_set(Ids,Pred,Info,CompSet) :-
1453 get_texpr_types(Ids,Types),
1454 couplise_list(Types,ElementType),
1455 create_texpr(comprehension_set(Ids,Pred),set(ElementType),Info,CompSet).
1456
1457
1458 :- assert_must_succeed(bsyntaxtree:nested_couple_to_list(b(couple(b(couple(a,b),x,[]),c),xx,[]),[a,b,c])).
1459 :- assert_must_succeed(bsyntaxtree:nested_couple_to_list(b(couple(a,c),x,[]),[a,c])).
1460 :- assert_must_succeed(bsyntaxtree:nested_couple_to_list(b(couple(a,b(couple(b,c),x,[])),xx,[]),[a,b(couple(b,c),x,[])])).
1461 nested_couple_to_list(NC,L) :- nested_couple_to_list_dcg(NC,L,[]).
1462 nested_couple_to_list_dcg(b(couple(A,B),_,_)) --> !,
1463 nested_couple_to_list_dcg(A), [B].
1464 nested_couple_to_list_dcg(E) --> [E].
1465
1466 % --------------------------------------
1467
1468
1469 % check if identifier(s) occur in typed expressions
1470
1471 occurs_in_expr(ID,TExpr) :- var(ID),!,
1472 add_internal_error('Variable id: ',occurs_in_expr(ID,TExpr)),fail.
1473 occurs_in_expr(ID,TExpr) :- ID=b(_,_,_),!, add_internal_error('Non-atomic identifier: ',occurs_in_expr(ID,TExpr)),fail.
1474 occurs_in_expr(ID,TExpr) :- ID=[_|_],!,
1475 add_internal_error('List instead of identifier: ',occurs_in_expr(ID,TExpr)),fail.
1476 occurs_in_expr(ID,TExpr) :- occurs_in_expr1(TExpr,ID).
1477
1478 % treat a few common operators here; possibly avoid traversing whole term if we find ID in a sub-tree
1479 occurs_in_expr1(TExpr,ID) :- TExpr = b(Expr,_,_),!,
1480 occurs_in_expr2(Expr,TExpr,ID).
1481 occurs_in_expr1(TExpr,ID) :- add_internal_error('Illegal typed expression:',occurs_in_expr1(TExpr,ID)).
1482
1483 occurs_in_expr2(add(A,B),_,ID) :- !,
1484 (occurs_in_expr1(A,ID) -> true ; occurs_in_expr1(B,ID)).
1485 occurs_in_expr2(conjunct(A,B),_,ID) :- !,
1486 (occurs_in_expr1(A,ID) -> true ; occurs_in_expr1(B,ID)).
1487 occurs_in_expr2(couple(A,B),_,ID) :- !,
1488 (occurs_in_expr1(A,ID) -> true ; occurs_in_expr1(B,ID)).
1489 occurs_in_expr2(member(A,B),_,ID) :- !,
1490 (occurs_in_expr1(A,ID) -> true ; occurs_in_expr1(B,ID)).
1491 occurs_in_expr2(equal(A,B),_,ID) :- !,
1492 (occurs_in_expr1(A,ID) -> true ; occurs_in_expr1(B,ID)).
1493 occurs_in_expr2(function(A,B),_,ID) :- !,
1494 (occurs_in_expr1(A,ID) -> true ; occurs_in_expr1(B,ID)).
1495 occurs_in_expr2(image(A,B),_,ID) :- !,
1496 (occurs_in_expr1(A,ID) -> true ; occurs_in_expr1(B,ID)).
1497 occurs_in_expr2(intersection(A,B),_,ID) :- !,
1498 (occurs_in_expr1(A,ID) -> true ; occurs_in_expr1(B,ID)).
1499 occurs_in_expr2(interval(A,B),_,ID) :- !,
1500 (occurs_in_expr1(A,ID) -> true ; occurs_in_expr1(B,ID)).
1501 occurs_in_expr2(not_equal(A,B),_,ID) :- !,
1502 (occurs_in_expr1(A,ID) -> true ; occurs_in_expr1(B,ID)).
1503 occurs_in_expr2(assertion_expression(A,_Msg,B),_,ID) :- !,
1504 (occurs_in_expr1(A,ID) -> true ; occurs_in_expr1(B,ID)).
1505 occurs_in_expr2(domain(A),_,ID) :- !, occurs_in_expr1(A,ID).
1506 occurs_in_expr2(range(A),_,ID) :- !, occurs_in_expr1(A,ID).
1507 occurs_in_expr2(record_field(A,_FieldName),_,ID) :- !, occurs_in_expr1(A,ID).
1508 occurs_in_expr2(identifier(ID1),_,ID) :- !,
1509 ID1 = ID.
1510 occurs_in_expr2(integer(_),_,_ID) :- !,fail.
1511 occurs_in_expr2(string(_),_,_ID) :- !,fail.
1512 occurs_in_expr2(value(_),_,_ID) :- !,fail.
1513 occurs_in_expr2(truth,_,_ID) :- !,fail.
1514 occurs_in_expr2(if_then_else(A,B,C),_,ID) :- !,
1515 (occurs_in_expr1(A,ID) -> true ; occurs_in_expr1(B,ID) -> true ; occurs_in_expr1(C,ID)).
1516 occurs_in_expr2(rec(Fields),_,ID) :- !,
1517 l_field_occurs_in_expr1(Fields,ID).
1518 occurs_in_expr2(set_extension(Elements),_,ID) :- !,
1519 l_occurs_in_expr1(Elements,ID).
1520 occurs_in_expr2(sequence_extension(Elements),_,ID) :- !,
1521 l_occurs_in_expr1(Elements,ID).
1522 occurs_in_expr2(Expr,_,ID) :-
1523 syntaxelement(Expr,List,[], [], [], _), % no bound quantifiers; TO DO: treat bound quantifiers
1524 !,
1525 l_occurs_in_expr1(List,ID).
1526 occurs_in_expr2(_E,TExpr,ID) :-
1527 %functor(_E,F,N), print(occurs_in_expr2(F,N,ID)),nl,
1528 (find_identifier_uses_if_necessary(TExpr,[],Used)
1529 -> %check_sorted(Used),
1530 %add_message(bsyntaxtree,'Occurs check: ',ID:Used,TExpr), translate:nested_print_bexpr(TExpr),nl,
1531 ord_member(ID,Used)
1532 ; add_failed_call_error(find_identifier_uses(TExpr,[],_)),fail).
1533 % TO DO: optimize so that we only look for ID; we don't have to keep track of other IDs
1534
1535 l_occurs_in_expr1([H|T],ID) :- !,
1536 (occurs_in_expr1(H,ID) -> true ; l_occurs_in_expr1(T,ID)).
1537 l_occurs_in_expr1(L,ID) :- L \= [],
1538 add_internal_error('Illegal typed expression list:',l_occurs_in_expr1(L,ID)).
1539 l_field_occurs_in_expr1([field(_,H)|T],ID) :- !,
1540 (occurs_in_expr1(H,ID) -> true ; l_field_occurs_in_expr1(T,ID)).
1541 l_field_occurs_in_expr1(L,ID) :- L \= [],
1542 add_internal_error('Illegal record field list:',l_field_occurs_in_expr1(L,ID)).
1543
1544 %check_sorted(List) :- sort(List,SL), (SL \= List -> add_internal_error('Not sorted:',List) ; true).
1545
1546 some_id_occurs_in_expr([H|T],TExpr) :- (var(H) ; \+ atomic(H) ; var(T) ; T=[H2|_], H2 @< H),
1547 add_internal_error('Must be (sorted) atomic identifiers: ',some_id_occurs_in_expr([H|T],TExpr)),
1548 fail.
1549 some_id_occurs_in_expr([Id],TExpr) :- !, % use version without complete find_identifier_uses
1550 occurs_in_expr(Id,TExpr).
1551 some_id_occurs_in_expr(SortedIDs,TExpr) :-
1552 find_identifier_uses_if_necessary(TExpr,[],Used),
1553 list_to_ord_set(Used,UsedSorted),
1554 ord_intersect(UsedSorted,SortedIDs).
1555
1556 % -----------------------------
1557
1558 % find used identifiers in typed expressions
1559
1560 % a special version for quantifier bodies, attempting to reuse used_ids info
1561 find_identifier_uses_for_quantifier_body(TIds,Body,Res) :-
1562 get_texpr_ids(TIds,Ids),
1563 list_to_ord_set(Ids,Ignore),
1564 find_identifier_uses_if_necessary(Body,Ignore,Res).
1565
1566 % only run find_identifier_uses if necessary because no used_ids Info field present
1567 % TO DO: we could consider using used_ids within find_typed_identifier_uses: drawback: we would need to store types
1568 find_identifier_uses_if_necessary(Expr,Ignore,Res) :-
1569 get_texpr_info(Expr,I),
1570 ? member(used_ids(UIds),I),!, %print('+'),nl,
1571 find_with_reuse(Expr,UIds,Ignore,Res).
1572 find_identifier_uses_if_necessary(Expr,Ignore,Res) :- find_identifier_uses(Expr,Ignore,Res).
1573
1574 find_with_reuse(Expr,UIds,Ignore,Res) :- preference(prob_safe_mode,true),
1575 !,
1576 (is_ordset(Ignore) -> true ; add_internal_error('Not ordset: ',Ignore)),
1577 (is_ordset(UIds) -> true ; add_internal_error('Not ordset: ',UIds)),
1578 ord_subtract(UIds,Ignore,Res0),
1579 find_identifier_uses(Expr,Ignore,Res1),
1580 (Res1=Res0 -> true
1581 ; ord_subtract(Res1,Res0,Miss), % missing
1582 ord_subtract(Res0,Res1,Res01), % too much
1583 (Miss=[] -> add_message(find_identifier_uses_if_necessary,'Suboptimal used_ids: ',Res01,Expr)
1584 ; add_internal_error('Incorrect used_ids:',used_ids(missing(Miss),toomuch(Res01),usedids(UIds),
1585 ignore(Ignore),real(Res1))),
1586 translate:print_bexpr(Expr),nl
1587 )
1588 ),
1589 Res=Res1.
1590 find_with_reuse(_,UIds,Ignore,Res) :-
1591 %(is_ordset(Ignore) -> true ; add_internal_error('Not ordset: ',Ignore)),
1592 ord_subtract(UIds,Ignore,Res).
1593
1594
1595 find_identifier_uses_top_level(TExpr,Ids) :-
1596 get_global_identifiers(Ignored), % ignore all global sets and global constants;
1597 % hence find_identifier_uses_top_level/2 usually should only be called for top level expressions
1598 find_identifier_uses(TExpr,Ignored,Ids).
1599
1600 :- use_module(tools,[safe_sort/3]).
1601 find_identifier_uses(TExpr,Ignored,Ids) :-
1602 %tools_printing:print_term_summary(find_identifier_uses(TExpr,Ignored,Ids)),nl,
1603 check_is_texpr(TExpr,find_identifier_uses),
1604 (find_typed_identifier_uses(TExpr,Ignored,TIds)
1605 -> get_texpr_ids(TIds,RIds),
1606 % in case of type errors, or when type checking is not yet complete, we can have multiple entries of the same identifier with different types !
1607 sort(RIds,Ids) % was remove_dups, but remove_dups just calls sort; TODO: implement get_sorted_texpr_ids
1608 ; add_internal_error('Call failed:',find_typed_identifier_uses(TExpr,Ignored,_)),
1609 Ids=[]
1610 ).
1611 find_identifier_uses_l(TExprs,Ignored,Ids) :-
1612 find_typed_identifier_uses_l(TExprs,Ignored,TIds),
1613 get_texpr_ids(TIds,RIds),
1614 sort(RIds,Ids). % see above
1615
1616 check_is_texpr(X,Context) :-
1617 (get_texpr_expr(X,_) -> true ; add_internal_error('Expected TExpr: ', check_is_texpr(X,Context))).
1618
1619 find_typed_identifier_uses(TExpr,Ids) :-
1620 get_global_identifiers(Ignored), % ignore all global sets and global constants; hence find_typed_identifier_uses/2 usually should only be called for top level expressions
1621 find_typed_identifier_uses(TExpr,Ignored,Ids).
1622
1623 find_typed_identifier_uses(TExpr,Ignored,Ids) :- var(TExpr),!,
1624 add_internal_error('Variable typed expression: ', find_typed_identifier_uses(TExpr,Ignored,Ids)),
1625 Ids = [].
1626 find_typed_identifier_uses(TExpr,Ignored,Ids) :-
1627 find_typed_identifier_uses_l([TExpr],Ignored,Ids).
1628
1629 find_typed_identifier_uses2(TExpr,Ignored,Ids,Rest) :-
1630 get_texpr_expr(TExpr,Expr),
1631 safe_syntaxelement_det(Expr,Subs,TNames,_,_), % QSubs=[],
1632 ( uses_an_identifier(Expr,Id,TExpr,Ignored) ->
1633 ( ord_member(Id,Ignored) -> Ids=Rest
1634 ;
1635 get_texpr_type(TExpr,Type),
1636 normalize_type(Type,NType), % replace seq by set;
1637 % warning: when type-check not yet complete we have variables here
1638 create_texpr(identifier(Id),NType,[],TId),
1639 %print(adding(Id,NType,Ignored)),nl,
1640 Ids = [TId|Rest]
1641 )
1642 % ; (Expr = becomes_such(TIds,_)), nl,print(uses_primes(Expr)),nl,fail
1643 ; indirectly_uses_identifiers(Expr,Ignored,IndirectIds) ->
1644 add_typed_ids(IndirectIds,Ids,Rest2),
1645 find_typed_identifier_uses2_l(Subs,Ignored,Rest2,Rest)
1646 ; TNames = [] -> find_typed_identifier_uses2_l(Subs,Ignored,Ids,Rest)
1647 ;
1648 %find_typed_identifier_uses2_l(QSubs,Ignored,Ids,Ids2), % useless here as QSubs=[]
1649 get_texpr_ids(TNames,Names),
1650 list_to_ord_set(Names,SNames), ord_union(SNames,Ignored,Ignored2),
1651 find_typed_identifier_uses2_l(Subs,Ignored2,Ids,Rest)).
1652 find_typed_identifier_uses2_l([],_) --> !, [].
1653 find_typed_identifier_uses2_l([Expr|Rest],Ignored) --> !,
1654 find_typed_identifier_uses2(Expr,Ignored),
1655 find_typed_identifier_uses2_l(Rest,Ignored).
1656 find_typed_identifier_uses2_l(E,Ignored) -->
1657 {add_internal_error('Illegal arguments (not a list):',find_typed_identifier_uses2_l(E,Ignored)),fail}.
1658
1659 %Note: above we do not remap uses of Id$0 to Id in becomes_such;
1660 % this is done in find_read_vars_for_becomes_such in b_read_write_info
1661
1662
1663 uses_an_identifier(Expr,Id) :- uses_an_identifier(Expr,Id,none,[]).
1664
1665 uses_an_identifier(identifier(Id),Id,_,_).
1666 uses_an_identifier(lazy_lookup_pred(Id),Id,_,_).
1667 uses_an_identifier(lazy_lookup_expr(Id),Id,_,_).
1668 uses_an_identifier(value(_),Id,b(_,_,Info),Ignored) :- Ignored \= [],
1669 member(was_identifier(Id),Info),
1670 member('$examine_value_was_identifier_info',Ignored),!.
1671
1672 % uses multiple ids and we also need to inspect subs (operation call arguments)
1673 indirectly_uses_identifiers(operation_call_in_expr(Operation,_),Ignored,IndirectIds) :-
1674 get_texpr_info(Operation,Info),
1675 (memberchk(reads(Vars),Info)
1676 -> (var(Vars) % can happen during initial computation of read_write info for recursive operation calls in expr
1677 -> add_message(bsyntaxtree,'Operation reads info not yet computed (probably recursive call): ',Operation,Info),
1678 fail % Assume this is a direct recursive call which adds no used ids,
1679 % case happens in test 1960 for recursive call to Fact; TODO: more robust solution or disallow recursion
1680 ; true)
1681 ; add_warning(bsyntaxtree,'Operation call contains no read infos:',Operation,Info),fail),
1682 ord_subtract(Vars,Ignored,IndirectIds),
1683 IndirectIds \= [].
1684 %indirectly_uses_identifiers(external_pred_call(FunName,_),Ignored,IndirectIds) :-
1685 % expects_state(FunName), TODO: check for which external functions/predicates we need to add ids
1686
1687
1688 % this is to convert untyped ids in operation call reads infos to typed ids
1689 add_typed_ids([]) --> [].
1690 add_typed_ids([Id|T]) --> {var_cst_type(Id,Type)},!,
1691 {create_texpr(identifier(Id),Type,[],TId)}, [TId], add_typed_ids(T).
1692 add_typed_ids([Id|T]) --> {debug_println(19,ignoring_used_id(Id))}, add_typed_ids(T).
1693
1694 :- use_module(bmachine,[bmachine_is_precompiled/0, b_is_variable/2,b_is_constant/2]).
1695 var_cst_type(Name,Type) :- bmachine_is_precompiled,!,
1696 (b_is_variable(Name,Type) ; b_is_constant(Name,Type)),!.
1697 var_cst_type(_,any). % TODO: provide a better solution; maybe only allow untyped find_identifier_uses ??
1698
1699 % -------------
1700
1701 find_typed_identifier_uses_l(TExprs,Ignored,Ids) :-
1702 check_atomic_ids(Ignored),
1703 list_to_ord_set(Ignored,SIgnored),
1704 find_typed_identifier_uses2_l(TExprs,SIgnored,Unsorted,[]),!,
1705 safe_sort(find_typed_identifier_uses,Unsorted,Ids),
1706 (preference(prob_safe_mode,true) -> check_typed_ids(Ids) ; true).
1707 find_typed_identifier_uses_l(TExprs,Ignored,Ids) :-
1708 add_internal_error('Call failed:',find_typed_identifier_uses_l(TExprs,Ignored,Ids)),
1709 fail.
1710
1711 check_typed_ids([]) :- !.
1712 check_typed_ids([b(identifier(ID),T,_)|Tail]) :- !, check_ids3(Tail,ID,T).
1713 check_typed_ids(Other) :- add_internal_error('Unexpected typed id list:',check_typed_ids(Other)).
1714
1715
1716 check_atomic_ids([]) :- !.
1717 check_atomic_ids([Id|_]) :- atomic(Id),!.
1718 check_atomic_ids(Other) :- add_internal_error('Expected atomic id list:',check_atomic_ids(Other)).
1719
1720
1721 check_ids3([],_,_) :- !.
1722 check_ids3([b(identifier(ID),T,_)|Tail],ID1,T1) :- !,
1723 (ID=ID1 -> add_internal_error('Identifier appears multiple times with types:',id(ID,T1,T)) ; true),
1724 check_ids3(Tail,ID,T).
1725 check_ids3(Other,ID1,T1) :- add_internal_error('Unexpected typed id list:',check_ids3(Other,ID1,T1)).
1726
1727
1728 update_used_ids(b(Pred,T,OInfo),UsedIds,b(Pred,T,[used_ids(UsedIds)|NInfo])) :-
1729 delete(OInfo,used_ids(_),NInfo).
1730
1731 % check if some pre-computed used ids are valid wrt find_typed_identifier_uses
1732 check_computed_used_ids(TExpr,CompUsedIds) :-
1733 find_identifier_uses(TExpr,[],RealUsedIds),
1734 (RealUsedIds=CompUsedIds -> print(ok(CompUsedIds)),nl
1735 ; add_error(range,'Unexpected used ids:',CompUsedIds,TExpr),
1736 format('Real: ~w~nComp: ~w~n',[RealUsedIds,CompUsedIds]),trace
1737 ).
1738
1739 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1740 % break predicate into components with disjunct identifiers
1741 % Pred: a predicate
1742 % Components: a list of terms component/2 where the first argument
1743 % is a predicate, the second is the set of used identifiers
1744 predicate_components(Pred,Res) :- predicate_components_in_scope(Pred,[],Res).
1745 predicate_components_in_scope(Pred,LocalVars,Res) :-
1746 predicate_components_with_restriction(Pred,LocalVars,all,Res).
1747
1748 predicate_components_with_restriction(Pred,LocalVars,RestrictionList,Res) :-
1749 conjunction_to_list(Pred,Preds),
1750 l_predicate_identifiers(Preds,LocalVars,PredIds),
1751 (RestrictionList=all -> R=all ; list_to_ord_set(RestrictionList,R)),
1752 try_find_and_remove_equalities(PredIds,PredIds2),
1753 % print(find_components(R)),nl,nl,
1754 %%(member(pred(P,Ids,X),PredIds2), nl,print(pred(Ids,X)),nl,translate:print_bexpr(P),nl,fail ; true),
1755 find_components(PredIds2,R,Components),
1756 !,
1757 %maplist(print_component,Components),
1758 Components=Res.
1759 predicate_components_with_restriction(Pred,_,_,[component(Pred,[])]) :-
1760 add_internal_error('predicate_components failed: ',predicate_components_with_restriction(Pred,_,_,_)).
1761
1762 % print_component(component(Pred,Ids)) :- format('Component over ~w :~n',[Ids]), translate:print_bexpr(Pred),nl.
1763
1764 % get the list of used identifiers for each predicate
1765 l_predicate_identifiers([],_LocalVars,[]).
1766 l_predicate_identifiers([Pred|PRest],LocalVars,[pred(Pred,Ids,_Selected)|IRest]) :-
1767 predicate_identifiers_in_scope(Pred,LocalVars,Ids), % Do not ignore local variables; used instead of enumerate set elements
1768 l_predicate_identifiers(PRest,LocalVars,IRest).
1769
1770
1771 try_find_and_remove_equalities(PredAndIds,PredAndIds2) :-
1772 preferences:get_preference(partition_predicates_inline_equalities,true),
1773 \+ preferences:get_preference(use_solver_on_load,kodkod),
1774 ? find_and_remove_equalities(PredAndIds,RR),
1775 !, PredAndIds2=RR.
1776 try_find_and_remove_equalities(Ps,Ps).
1777
1778 :- use_module(debug,[debug_println/2]).
1779 % find and apply obvious equalities so that they do not interfere with partitioning into components
1780 % example: c = 1 & f: 1..c --> A & g: 1..c --> B
1781 % TO DO: preprocess and do one pass to detect potential equalities
1782 find_and_remove_equalities([],[]).
1783 find_and_remove_equalities(List,[pred(P,PIds,Sel)|FT]) :-
1784 ? select(pred(P,PIds,Sel),List,Rest),
1785 %PIds = [Id],
1786 identifier_equality(P,Id,Value),
1787 %(value_which_can_be_replaced(Value) -> true ; nl,print('Not replaced: '),translate:print_bexpr(Value),nl,fail),
1788 (get_texpr_id(Value,Id2)
1789 -> Id2 \= Id %,print(inline_id(Id,Id2)),nl
1790 % Note: this inlining does *not* help with partitioning; but does help ProB detect common predicates/expressions
1791 ; PIds=[Id],value_which_can_be_replaced(Value)),
1792 debug_println(9,replace_simple_equality(Id,PIds)),
1793 maplist(apply_to_pred(Id,Value),Rest,RT),
1794 !,
1795 ? find_and_remove_equalities(RT,FT).
1796 % TO DO: detect equalityes x = EXPR, where EXPR does not contain x and where x occurs in no other predicate
1797 % we can then annotate x as not to enumerate
1798 find_and_remove_equalities(R,R).
1799
1800 identifier_equality(b(equal(LHS,RHS),_,_),Id,EqTerm) :-
1801 (get_texpr_id(LHS,Id) -> EqTerm = RHS
1802 ; get_texpr_id(RHS,Id) -> EqTerm = LHS).
1803 % TO DO: should we detect other equalities?
1804
1805 value_which_can_be_replaced(b(E,T,_)) :- value_which_can_be_replaced2(E,T).
1806 %(value_which_can_be_replaced2(E,T) -> true ; print(not_val(E)),nl,fail).
1807 value_which_can_be_replaced2(value(_),_).
1808 value_which_can_be_replaced2(integer(_),_).
1809 %value_which_can_be_replaced2(identifier(I),global(G)) :- b_global_constant(G), id_not_used_anywhere(I).
1810 value_which_can_be_replaced2(integer_set(_),_).
1811 value_which_can_be_replaced2(unary_minus(A),_) :- value_which_can_be_replaced(A).
1812 value_which_can_be_replaced2(add(A,B),_) :- value_which_can_be_replaced(A), value_which_can_be_replaced(B).
1813 % we could compute the value
1814 value_which_can_be_replaced2(minus(A,B),_) :- value_which_can_be_replaced(A), value_which_can_be_replaced(B).
1815 value_which_can_be_replaced2(multiplication(A,B),_) :- value_which_can_be_replaced(A), value_which_can_be_replaced(B).
1816 value_which_can_be_replaced2(div(A,B),_) :-
1817 get_integer(B,IB), IB \= 0,
1818 value_which_can_be_replaced(A).
1819 value_which_can_be_replaced2(floored_div(A,B),T) :- value_which_can_be_replaced2(div(A,B),T).
1820 % should we add: with WD check: division, modulo, .... ? see also simple2 in b_ast_cleanup
1821 value_which_can_be_replaced2(max_int,_).
1822 value_which_can_be_replaced2(min_int,_).
1823 value_which_can_be_replaced2(float_set,_).
1824 value_which_can_be_replaced2(real(_),_).
1825 value_which_can_be_replaced2(real_set,_).
1826 value_which_can_be_replaced2(string(_),_).
1827 value_which_can_be_replaced2(string_set,_).
1828 value_which_can_be_replaced2(boolean_true,_).
1829 value_which_can_be_replaced2(boolean_false,_).
1830 value_which_can_be_replaced2(bool_set,_).
1831 value_which_can_be_replaced2(empty_set,_).
1832 value_which_can_be_replaced2(empty_sequence,_).
1833 value_which_can_be_replaced2(couple(A,B),_) :- value_which_can_be_replaced(A), value_which_can_be_replaced(B).
1834 value_which_can_be_replaced2(interval(A,B),_) :- value_which_can_be_replaced(A), value_which_can_be_replaced(B).
1835 value_which_can_be_replaced2(set_extension(L),_) :- maplist(value_which_can_be_replaced,L).
1836 value_which_can_be_replaced2(sequence_extension(L),_) :- maplist(value_which_can_be_replaced,L).
1837 value_which_can_be_replaced2(cartesian_product(A,B),_) :- % typing equations, like t_float = INTEGER*NATURAL1
1838 simple_value_set(A), simple_value_set(B).
1839 value_which_can_be_replaced2(pow_subset(A),_) :- simple_value_set(A).
1840 %value_which_can_be_replaced2(identifier(_),_). % TO DO: check that this is not the LHS identifier which we replace !!
1841 % identifiers can also be replaced: we check above that the only identifier in the predicate is the equality identifier
1842 % TO DO: enable this but then we need to fix replace_id_by_expr2 to updated the used_ids info ! + we can have scoping issues !?; see test 1358
1843
1844 % TO DO: also allow inlining of prj1/prj2 of simple_value_set:
1845 % not_val(comprehension_set([b(identifier(_zzzz_unary),integer,[generated(first)]),b(identifier(_zzzz_binary),integer,[generated(first)]),b(identifier(_lambda_result_),integer,[lambda_result])],b(equal(b(identifier(_lambda_result_),integer,[lambda_result]),b(identifier(_zzzz_unary),integer,[generated(first)])),pred,[prob_annotation(LAMBDA),lambda_result])))
1846 % not_val(comprehension_set([b(identifier(_zzzz_unary),integer,[generated(second)]),b(identifier(_zzzz_binary),integer,[generated(second)]),b(identifier(_lambda_result_),integer,[lambda_result])],b(equal(b(identifier(_lambda_result_),integer,[lambda_result]),b(identifier(_zzzz_binary),integer,[generated(second)])),pred,[prob_annotation(LAMBDA),lambda_result])))
1847
1848 % TO DO: maybe check if it is an infinite type which cannot be evaluated anyway
1849 simple_value_set(b(E,_,_)) :- simple_value_set2(E).
1850 %simple_value_set2(bool_set). % Warning: we could have a finite construct which gets evaluated multiple times
1851 simple_value_set2(string_set).
1852 simple_value_set2(integer_set(_)).
1853 simple_value_set2(float_set).
1854 simple_value_set2(real_set).
1855 simple_value_set2(cartesian_product(A,B)) :- simple_value_set(A), simple_value_set(B).
1856 simple_value_set2(pow_subset(A)) :- simple_value_set(A).
1857 % POW, records struct(_) set ?
1858
1859 % apply a substiution of ID/Expr on a pred(EXPR,VarList,X) term
1860 % Expr must either be a variable or contain no variables at all
1861 apply_to_pred(ID,Expr,pred(E1,PIds1,X),pred(E2,PIds3,X)) :-
1862 ? (select(ID,PIds1,PIds2)
1863 -> replace_id_by_expr(E1,ID,Expr,E2), %,print(applied(ID)),nl,translate:print_bexpr(E2),nl
1864 % TO DO: replace_id_by_expr does not seem to update used_ids info !! check_used_ids_info fails for test 1358 if we allow identifiers inside Expr
1865 (get_texpr_id(Expr,NewID)
1866 -> ord_add_element(PIds2,NewID,PIds3)
1867 ; PIds3 = PIds2)
1868 %, format('Apply ~w -> ~w : ',[ID,NewID]),translate:print_bexpr(E2),nl
1869 ; E1=E2,PIds1=PIds3).
1870
1871
1872 % project a predicate : keep only those Predicates that are directly or
1873 % indirectly relevant for Ids; FullIds are all identifiers used by ProjectedPredicate
1874 project_predicate_on_identifiers(Pred,Ids,ProjectedPredicate,FullIds, RestList) :-
1875 (debug_mode(on)
1876 -> print('project: '),print_bexpr(Pred),nl, print(' on : '), print(Ids),nl
1877 ; true),
1878 conjunction_to_list(Pred,Preds),
1879 l_predicate_identifiers(Preds,[],PredIds), % TO DO: allow LocalVariables to be passed
1880 % print(predids(PredIds)),nl,
1881 try_find_and_remove_equalities(PredIds,PredIds2),
1882 extract_all_predicates(Ids,all,Ids,PredIds2,ProjectedPredicates, RestList,FullIds),
1883 conjunct_predicates(ProjectedPredicates,ProjectedPredicate),
1884 (debug_mode(on)
1885 -> print('*result: '),print_bexpr(ProjectedPredicate),nl,
1886 print(' on : '), print(FullIds),nl
1887 ; true).
1888
1889 %print_preds([]).
1890 %print_preds([pred(P,_IDs,_)|T]) :- translate:print_bexpr(P), nl, print(' '), print_preds(T).
1891
1892 :- use_module(b_global_sets,[b_get_global_constants/1, b_get_enumerated_set_constants/1, b_get_global_sets/1]).
1893 predicate_identifiers(Pred,Ids) :- predicate_identifiers_in_scope(Pred,[],Ids).
1894 predicate_identifiers_in_scope(Pred,LocalVariables,Ids) :-
1895 get_global_identifiers(IS),
1896 list_to_ord_set(LocalVariables,LV),
1897 ord_subtract(IS,LV,Ignore2), % Do not ignore any local variable; it will be used instead of enumerate set element
1898 find_identifier_uses_if_necessary(Pred,Ignore2,Ids1), % Ignore enumerated set names
1899 list_to_ord_set(Ids1,Ids).
1900
1901 get_global_identifiers(IDs) :- get_global_identifiers(IDs,all).
1902 % get global set and constant identifiers which you usually want to exclude for find_identifier_uses
1903 get_global_identifiers(IDs,Option) :-
1904 (Option=ignore_promoted_constants
1905 % do not include those constants that have been automatically promoted as enumerated set elements
1906 -> b_get_enumerated_set_constants(EnumeratedSetCsts)
1907 ; b_get_global_constants(EnumeratedSetCsts)
1908 ),
1909 % b_global_sets:b_get_global_enumerated_sets(GSets), % is there a reason to exclude deferred sets ??; cardinality inference,... are all done before partitioning ?
1910 b_get_global_sets(GSets),
1911 append(GSets,EnumeratedSetCsts,GE),
1912 list_to_ord_set(GE,IDs).
1913
1914 % find_components(ListOf_pred, Restrict, Out:ListOfComponents)
1915 % role of Restrict: all if we do normal partition or List of VariableIDs on which we restrict our attention to (for Existential quantifier construction)
1916 find_components([],_,[]).
1917 find_components([pred(P,PIds,true)|PRest],Restrict,[component(Pred,Ids)|CRest]) :-
1918 % find all predicates which are using identifiers occuring in PIds
1919 % (and additionally those which use common identifiers )
1920 ord_restrict(Restrict,PIds,InterIDs),
1921 %format('Treating predicate with ids ~w; restr. intersect = ~w~n',[PIds,InterIDs]),
1922 ( InterIDs =[] ->
1923 % we simply copy this predicate into a single component; not with the scope of Restricted IDs
1924 % print(skip(PIds,P)),nl, %
1925 Pred=P, Ids=PIds, PRest=Rest
1926 ;
1927 extract_all_predicates(InterIDs,Restrict,PIds,PRest,Preds,Rest,Ids),
1928 %length([P|Preds],Len), format('Detected component with ~w conjuncts over ~w~n',[Len,Ids]),
1929 conjunct_predicates_with_pos_info([P|Preds],Pred)
1930 ),
1931 find_components(Rest,Restrict,CRest).
1932 extract_all_predicates([],_,_,Preds,Found,Rest,[]) :- !, % selecting done at end: keep same order of conjuncts
1933 select_predicates(Preds,Found,Rest).
1934 extract_all_predicates(Ids,Restrict,OldIds,Preds,Found,Rest,ResultIds) :-
1935 % search for all predicates that directly use one of the
1936 % identifiers in "Ids"
1937 select_all_using_preds(Preds,Ids,FoundIds),
1938 ord_subtract(FoundIds,OldIds,NewIds),
1939 ord_restrict(Restrict,NewIds,NewIdsToExtract),
1940 ord_union(OldIds,FoundIds,OldIds2),
1941 % now recursively do this which the new identifiers that we have found
1942 extract_all_predicates(NewIdsToExtract,Restrict,OldIds2,Preds,Found,Rest,RestIds),
1943 ord_union([Ids,NewIds,RestIds],ResultIds).
1944
1945 % mark all predicates which intersect with ComponentIds and compute new ids to be added to the component
1946 select_all_using_preds([],_,[]).
1947 select_all_using_preds([pred(_P,PIds,Selected)|PRest],ComponentIds,NewFoundIds) :-
1948 ( (Selected==true ; ord_disjoint(PIds,ComponentIds)) ->
1949 NewFoundIds1 = []
1950 ; % we select the predicate for the component
1951 ord_subtract(PIds,ComponentIds,NewFoundIds1),
1952 Selected=true
1953 ),
1954 select_all_using_preds(PRest,ComponentIds,NewFoundIds2),
1955 ord_union(NewFoundIds1,NewFoundIds2,NewFoundIds).
1956
1957 % ord_intersection with special case for all term
1958 ord_restrict(all,Ids,Res) :- !, Res=Ids.
1959 ord_restrict(Restrict,Ids,Res) :- ord_intersection(Ids,Restrict,Res).
1960
1961 select_predicates(Predicates,FoundPreds,OtherPreds) :-
1962 split_list(is_selected_predicate,Predicates,FoundPredIds,OtherPreds),
1963 maplist(extract_found_predicate,FoundPredIds,FoundPreds).
1964 is_selected_predicate(pred(_P,_PIds,Selected)) :- ground(Selected).
1965 extract_found_predicate(pred(P,_PIds,_Selected),P).
1966
1967 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
1968 % replace (simultaneously) multiple identifiers by expressions
1969 % this could be used to replace the predicate replace_id_by_expr by mapping everything in a
1970 % singleton list. however, that would involve list operations instead of unifications
1971 parse_pred(Codes,TExpr) :- %format('Parsing ~s~n',[Codes]),
1972 bmachine:b_parse_machine_predicate_from_codes_open(no_quantifier,Codes,[],[],TExpr).
1973 parse_expr(Codes,TExpr) :- bmachine:b_parse_machine_expression_from_codes(Codes,[],TExpr,_Type,true,_Error).
1974 test_result(1,b(equal(b(comprehension_set([b(identifier(__FRESH____),integer,_)],
1975 b(greater(b(identifier(__FRESH____2),integer,_),b(identifier(x),integer,_)),pred,_)),set(integer),_),
1976 b(empty_set,set(integer),_)),pred,_)).
1977
1978 :- assert_must_succeed((bsyntaxtree:parse_pred("{x|x:INTEGER & x>y}={}",T1), replace_ids_by_exprs(T1,[],[],T1))).
1979 :- assert_must_succeed((bsyntaxtree:parse_pred("{x|x:INTEGER & x>y}={}",T1), bsyntaxtree:parse_expr("100",T2),
1980 replace_ids_by_exprs(T1,[y],[T2],R),bsyntaxtree:parse_pred("{x|x>100}={}",T3),same_texpr(R,T3) )).
1981 :- assert_must_succeed((bsyntaxtree:parse_pred("{x|x:INTEGER & x>y}={}",T1),
1982 replace_ids_by_exprs(T1,[y],[b(identifier(x),integer,[])],R),
1983 bsyntaxtree:test_result(1,R),bsyntaxtree:parse_pred("{x|x:INTEGER & x>x}={}",T3),\+ same_texpr(R,T3) )).
1984 :- assert_must_succeed((bsyntaxtree:parse_pred("{x,y|x:INTEGER & y:INTEGER & x>v & y>w}={}",T1),
1985 replace_ids_by_exprs(T1,[v,w],[b(identifier(w),integer,[]),b(identifier(v),integer,[])],R),
1986 bsyntaxtree:parse_pred("{x,y|x:INTEGER & y:INTEGER & x>w & y>v}={}",T3), same_texpr(R,T3) )).
1987 :- assert_must_succeed((gensym:reset_gensym, bsyntaxtree:parse_pred("{x,y|x:INTEGER & y:INTEGER & x>v & y>w}={}",T1),
1988 replace_ids_by_exprs(T1,[v,w],[b(identifier(w),integer,[]),b(identifier(x),integer,[])],R),
1989 translate:translate_bexpression(R,TR),
1990 TR = '{`__FRESH____1`,y|`__FRESH____1` > w & y > x} = {}')). %'{__FRESH____1,y|(__FRESH____1 : INTEGER & y : INTEGER) & (__FRESH____1 > w & y > x)} = {}' )).
1991
1992 replace_ids_by_exprs(TExpr,[TId],[Inserted],Replaced) :- !, % better, more robust and efficient version
1993 check_ids([TId],[Id]),
1994 replace_id_by_expr(TExpr,Id,Inserted,Replaced).
1995 replace_ids_by_exprs(TExpr,[],[],Replaced) :- !, Replaced=TExpr. % Nothing to do
1996 replace_ids_by_exprs(TExpr,Ids,Exprs,Replaced) :-
1997 check_ids(Ids,Ids2), % convert to atomic identifiers
1998 find_identifier_uses_l(Exprs,[],ExprsUsedIds),
1999 sort(ExprsUsedIds,SExprsUsedIds),
2000 generate_rename_list(Ids2,Exprs,RenameList),
2001 %print(replace(RenameList,SExprsUsedIds)),nl,
2002 replace_ids_by_exprs2(RenameList,SExprsUsedIds,TExpr,Replaced,_). %, nl,print(done),nl.
2003 % a version of replace_ids_by_exprs2 for maplist:
2004 %replace_ids_by_exprs1(RenameList,SExprsUsedIds,TExpr,Replaced) :-
2005 % replace_ids_by_exprs2(RenameList,SExprsUsedIds,TExpr,Replaced,_). %, print('Rep: '), translate:print_bexpr(Replaced),nl.
2006
2007 generate_rename_list([],[],[]).
2008 generate_rename_list([ID1|T],[Expr1|TE],[rename(ID1,Expr1)|RT]) :- generate_rename_list(T,TE,RT).
2009
2010 check_ids([],[]).
2011 check_ids([H|T],[ID|IT]) :- (atomic(H) -> ID=H ; def_get_texpr_id(H,ID)), check_ids(T,IT).
2012 replace_ids_by_exprs2(RenameList,ExprsUsedIds,TExpr,Replaced,WDC) :-
2013 remove_bt(TExpr,Expr,NewExpr,TNewExpr),
2014 ? ( Expr = identifier(Id), member(rename(Id,Inserted),RenameList) ->
2015 Replaced = Inserted,
2016 get_texpr_info(Inserted,Infos),
2017 (memberchk(contains_wd_condition,Infos)
2018 -> WDC = true ; WDC = false) % WDC = true means we have added a wd-condition where previously there was none
2019 ; contains_no_ids(Expr) -> Replaced=TExpr, WDC=false
2020 ;
2021 syntaxtransformation_det(Expr,Subs1,Names,NSubs,NewExpr),
2022 find_variable_clashes(Names,ExprsUsedIds,RenameNames), % check for variable caputure
2023 (RenameNames = []
2024 -> Subs = Subs1 % no variable capture occured
2025 ; %format('*** VARIABLE CAPTURE : ~w~n~n',[RenameNames]),
2026 rename_bt_l(Subs1,RenameNames,Subs) % replace affected names by fresh ids in sub arguments (will also change list of quantified variables itself)
2027 ),
2028 %l_replace_ids_by_exprs2(QSubs,RenameList,ExprsUsedIds,NQSubs,WDC1), % QSubs are like RHS of let expression, where Names are not in scope
2029 remove_hidden_names(Names,RenameList,UpdatedRenameList),
2030 ( UpdatedRenameList = [] -> % all Ids are now hidden for the inner expressions
2031 NSubs=Subs, WDC=false
2032 ;
2033 l_replace_ids_by_exprs2(Subs,UpdatedRenameList,ExprsUsedIds,NSubs,WDC)
2034 ),
2035 TNewExpr = b(E1,T1,Info1),
2036 rename_update_used_ids_info(RenameList,Info1,Info2),
2037 add_wd_if_needed(WDC,b(E1,T1,Info2),Replaced)
2038 ).
2039
2040 contains_no_ids(integer(_)).
2041 contains_no_ids(string(_)).
2042 contains_no_ids(value(_)).
2043
2044
2045 % check if we have to rename any quantified variable to avoid variable capture of RHS of renamings
2046 % example, suppose we rename x/y+1 and we enter {y|y>x} we have to generate {fresh|fresh>y+1} and *not* {y|y>y+1}
2047 find_variable_clashes([],_,[]).
2048 find_variable_clashes([Name|Names],ExprsUsedIds,[rename(ID,FRESHID)|Renaming] ) :-
2049 def_get_texpr_id(Name,ID),
2050 ord_member(ID,ExprsUsedIds), % the quantified name is also introduced by the renaming
2051 !,
2052 gensym('__FRESH__',FRESHID),
2053 find_variable_clashes(Names,ExprsUsedIds,Renaming).
2054 find_variable_clashes([_|Names],ExprsUsedIds,Renaming) :-
2055 find_variable_clashes(Names,ExprsUsedIds,Renaming).
2056
2057
2058 l_replace_ids_by_exprs2([],_,_,[],false).
2059 l_replace_ids_by_exprs2([H|T],UpdatedRenameList,ExprsUsedIds,[IH|IT],WDC) :-
2060 replace_ids_by_exprs2(UpdatedRenameList,ExprsUsedIds,H,IH,WDC1),
2061 l_replace_ids_by_exprs2(T,UpdatedRenameList,ExprsUsedIds,IT,WDC2),
2062 and_wdc(WDC1,WDC2,WDC).
2063
2064 % remove any identifiers that are now "invisible" because they are masked by quantified names
2065 % e.g., when we enter #x.(P) then a renaming of x will be "hidden" inside P
2066 remove_hidden_names([],RenameList,RenameList).
2067 remove_hidden_names([Name|Names],RenameList,NewRenameList) :-
2068 def_get_texpr_id(Name,ID),
2069 delete(RenameList,rename(ID,_),RenameList1),
2070 !, % only one rename should exist
2071 %print(del(ID,RenameList1)),nl,
2072 remove_hidden_names(Names,RenameList1,NewRenameList).
2073
2074 find_rhs_ids(rename(Id,TExpr),rename_ids(Id,InsUsedIds)) :- find_identifier_uses(TExpr,[],InsUsedIds).
2075
2076 % apply a rename list to the used_ids,... information fields
2077 % this is more tricky than applying a single identifier, as we first have to deleted all ids
2078 % and remember which ones were deleted, and only then insert the corresponding ids
2079 % e.g., we could have a RenameList = [rename(p,q),rename(q,p)] ; see test 1776 M1_Internal_v3.mch
2080 rename_update_used_ids_info(RenameList,IIn,IOut) :-
2081 l_find_rhs_ids(RenameList,RenameList2),
2082 %maplist(apply_rename_list(RenameList2),IIn,IOut).
2083 l_apply_rename_list(IIn,RenameList2,IOut).
2084
2085 l_find_rhs_ids([],[]).
2086 l_find_rhs_ids([R1|T],[NR1|NTR]) :-
2087 find_rhs_ids(R1,NR1),
2088 l_find_rhs_ids(T,NTR).
2089
2090 l_apply_rename_list([],_,[]).
2091 l_apply_rename_list([Info1|T],RenameList2,[NewInfo1|NTI]) :-
2092 apply_rename_list(RenameList2,Info1,NewInfo1),
2093 l_apply_rename_list(T,RenameList2,NTI).
2094
2095 apply_rename_list(RenameList,I,NI) :-
2096 apply_rename_list2(I,RenameList,NI).
2097 apply_rename_list2(used_ids(IDS),RenameList,used_ids(NewIDS)) :- !, apply_rename_list_to_ids(RenameList,IDS,[],NewIDS).
2098 apply_rename_list2(reads(IDS),RenameList,reads(NewIDS)) :- !, apply_rename_list_to_ids(RenameList,IDS,[],NewIDS).
2099 apply_rename_list2(modifies(IDS),RenameList,modifies(NewIDS)) :- !, apply_rename_list_to_ids(RenameList,IDS,[],NewIDS).
2100 apply_rename_list2(Info,_,Info).
2101
2102 % apply a rename list to a sorted list of ids
2103 apply_rename_list_to_ids([],Acc,ToInsert,Res) :- ord_union(Acc,ToInsert,Res).
2104 apply_rename_list_to_ids([rename_ids(Id,NewIds)|T],Acc,ToInsert,Res) :-
2105 (ord_delete_existing_element(Acc,Id,Acc2) % the Id occurs and is deleted
2106 -> ord_union(NewIds,ToInsert,ToInsert2),
2107 apply_rename_list_to_ids(T,Acc2,ToInsert2,Res)
2108 ; apply_rename_list_to_ids(T,Acc,ToInsert,Res)).
2109
2110 ord_delete_existing_element(List,El,ResList) :- % ord_del_element also succeeds if El is not in the list !
2111 ord_intersection([El],List,[El],ResList).
2112 % -----------------------
2113 % remove an Identifier from used_ids Info field if it exists
2114 remove_used_id_from_info(I,ID_to_remove,NI) :-
2115 update_used_ids_info(I,ID_to_remove,[],NI).
2116
2117 remove_used_ids_from_info([],I,I).
2118 remove_used_ids_from_info([ID_to_remove|T],I,NI) :- remove_used_id_from_info(I,ID_to_remove,I2),
2119 remove_used_ids_from_info(T,I2,NI).
2120
2121 % remove a single Identifier from used_ids Info field if it exists and insert sorted list of ids instead
2122 % a simpler version of rename_update_used_ids_info for a single identifier
2123 update_used_ids_info([],_,_,[]).
2124 update_used_ids_info([InfoField|T],ID_to_remove,IDsInserted,[NewInfoField|NT]) :-
2125 (update_id_from_info_field(ID_to_remove,IDsInserted,InfoField,R)
2126 -> NewInfoField=R
2127 ; NewInfoField=InfoField),
2128 update_used_ids_info(T,ID_to_remove,IDsInserted,NT).
2129
2130 update_id_from_info_field(ID_to_remove,IDsInserted,I,NI) :-
2131 update_id_from_info_field2(I,ID_to_remove,IDsInserted,NI).
2132 update_id_from_info_field2(used_ids(IDS),ID,IDsInserted,used_ids(NewIDS)) :- update_id(IDS,ID,IDsInserted,NewIDS).
2133 update_id_from_info_field2(reads(IDS),ID,IDsInserted,reads(NewIDS)) :- update_id(IDS,ID,IDsInserted,NewIDS).
2134 update_id_from_info_field2(modifies(IDS),ID,IDsInserted,modifies(NewIDS)) :- update_id(IDS,ID,IDsInserted,NewIDS).
2135
2136 update_id(IDS,ID_to_remove,IDsInserted,NewIDS) :-
2137 ord_delete_existing_element(IDS,ID_to_remove,IDS2), % the Id occurs and is deleted
2138 ord_union(IDsInserted,IDS2,NewIDS).
2139 %if ord_del_element fails we do not add IDsInserted: we assume the used_ids info is correct and ID_to_remove does not occur !
2140 % We could use this info to avoid traversing subtree !
2141 % print(projecting_away_unknown_id(ID_to_remove,IDS)),nl,
2142
2143 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
2144
2145 :- assert_must_succeed((gensym:reset_gensym, bsyntaxtree:exists_ast(A), replace_id_by_expr(A,y,b(identifier(x),integer,[]),RA),translate:translate_bexpression(RA,TR),
2146 TR = 'r = {`__FRESH____1`|`__FRESH____1` : 1 .. x & `__FRESH____1` mod 2 = 1}' )).
2147 :- assert_must_succeed((bsyntaxtree:parse_pred("{x|x:INTEGER & x>y}={}",T1),
2148 replace_id_by_expr(T1,y,b(identifier(x),integer,[]),R),
2149 bsyntaxtree:test_result(1,R),bsyntaxtree:parse_pred("{x|x:INTEGER & x>x}={}",T3),
2150 \+ same_texpr(R,T3) )).
2151 :- assert_must_succeed((bsyntaxtree:parse_pred("{x|x:INTEGER & x>y}={}",T1), bsyntaxtree:parse_expr("100",T2),
2152 replace_id_by_expr(T1,y,T2,R),bsyntaxtree:parse_pred("{x|x>100}={}",T3),same_texpr(R,T3) )).
2153
2154 % replace an identifier Id by an expression Inserted
2155 replace_id_by_expr(TExpr,Id,Inserted,Replaced) :-
2156 replace_id_by_expr_with_count(TExpr,Id,Inserted,Replaced,_).
2157
2158 replace_id_by_expr_with_count(TExpr,Id,Inserted,Replaced,NrReplacements) :- \+ atomic(Id),!,
2159 add_internal_error('Id not atomic: ',replace_id_by_expr(TExpr,Id,Inserted,Replaced)),
2160 Replaced = TExpr, NrReplacements=0.
2161 replace_id_by_expr_with_count(TExpr,Id,Inserted,Replaced,NrReplacements) :-
2162 %find_all_relevant_quantified_vars(Id,TExpr,QVars),
2163 find_identifier_uses(Inserted,[],SInsUsedIds), % SInsUsedIds is sorted
2164 replace_id_by_expr2(Id,Inserted,SInsUsedIds,TExpr,Replaced,_WDC,0,NrReplacements).
2165
2166 replace_id_by_expr2(Id,Inserted,InsUsedIds,TExpr,Replaced,WDC,InR,OutR) :-
2167 remove_bt(TExpr,Expr,NewExpr,TNewExpr),
2168 ( Expr = identifier(Id) -> % TODO: count number of replacements
2169 Replaced = Inserted,
2170 OutR is InR+1,
2171 get_texpr_info(Inserted,Infos),
2172 (memberchk(contains_wd_condition,Infos)
2173 -> WDC = true ; WDC = false) % WDC = true means we have added a wd-condition where previously there was none
2174 ; contains_no_ids(Expr) -> Replaced=TExpr, WDC=false, OutR=InR
2175 ;
2176 syntaxtransformation_det(Expr,Subs,Names,NSubs,NewExpr),
2177 get_texpr_id(TId,Id),
2178 ( memberchk(TId,Names) -> % the Id is now hidden for the inner expressions
2179 NSubs=Subs, WDC=false, OutR = InR
2180 ; (InsUsedIds \= [],
2181 get_texpr_ids(Names,Ns),sort(Ns,SNs),
2182 ord_intersection(SNs,InsUsedIds,Captured),
2183 Captured \= [] %, print(inter(SNs,InsUsedIds,Captured)),nl
2184 )
2185 % The Names introduced clash with variables used in the Inserted expression
2186 -> findall(rename(X,FRESHID),(member(X,Captured),gensym:gensym('__FRESH__',FRESHID)),RenameList),
2187 %print(rename(RenameList)),nl,
2188 rename_bt_l(Subs,RenameList,RenSubs),
2189 l_replace_id_by_expr2(RenSubs,Id,Inserted,InsUsedIds,NSubs,WDC,InR,OutR)
2190 ;
2191 l_replace_id_by_expr2(Subs,Id,Inserted,InsUsedIds,NSubs,WDC,InR,OutR)
2192 ),
2193 TNewExpr = b(E1,T1,Info1),
2194 update_used_ids_info(Info1,Id,InsUsedIds,Info2),
2195 %(E1 = exists(P,_) -> print(exists(P,Id,Info1,Info2)),nl ; true),
2196 add_wd_if_needed(WDC,b(E1,T1,Info2),Replaced)
2197 ).
2198
2199 l_replace_id_by_expr2([],_,_,_,[],false,R,R).
2200 l_replace_id_by_expr2([H|T],Id,Inserted,InsUsedIds,[IH|IT],WDC,InR,OutR) :-
2201 replace_id_by_expr2(Id,Inserted,InsUsedIds,H,IH,WDC1,InR,InR2),
2202 l_replace_id_by_expr2(T,Id,Inserted,InsUsedIds,IT,WDC2,InR2,OutR),
2203 and_wdc(WDC1,WDC2,WDC).
2204
2205 % conjunct wd condition added flag
2206 and_wdc(true,_,R) :- !,R=true.
2207 and_wdc(_,true,R) :- !, R=true.
2208 and_wdc(_,_,false).
2209
2210 % add contains_wd_condition if a change occured during replacement of id by expression
2211 add_wd_if_needed(true,b(E,T,Infos),Replaced) :-
2212 nonmember(contains_wd_condition,Infos),
2213 !,
2214 Replaced = b(E,T,[contains_wd_condition|Infos]).
2215 add_wd_if_needed(_,T,T).
2216
2217
2218
2219 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
2220
2221
2222 % syntaxtransformation_fixed/7 is the same as syntaxtransformation/5 with the exception
2223 % that we distinguish between subexpressions that have the newly introduced identifiers (Names)
2224 % in scope (OSubs) and those who don't (OExprs). The only expressions where the latter case is relevant
2225 % are let_expression and let_predicate.
2226 % TODO: This is a quick'n dirty fix for only some cases.
2227 % NO LONGER REQUIRED: let_expression and let_predicate now obey another semantic, not the Z semantics anymore
2228 %syntaxtransformation_fixed(OExpr,OExprs,OSubs,Names,NExprs,NSubs,NExpr) :-
2229 %syntaxtransformation_fixed(Expr,[],Subs,Names,[],NSubs,NExpr) :-
2230 % syntaxtransformation_det(Expr,Subs,Names,NSubs,NExpr).
2231
2232
2233 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
2234 % rename identifier
2235
2236 % r = {x|x : 1..y & x mod 2 = 1}
2237 exists_ast(AST) :- AST =
2238 b(equal(b(identifier(r),set(integer),[nodeid(none)]),
2239 b(comprehension_set([b(identifier(x),integer,[nodeid(none)])],
2240 b(conjunct(b(member(b(identifier(x),integer,[nodeid(none)]),
2241 b(interval(b(integer(1),integer,[nodeid(none)]),b(identifier(y),integer,[nodeid(none)])),
2242 set(integer),[nodeid(none)])),pred,[nodeid(none)]),
2243 b(equal(b(modulo(b(identifier(x),integer,[nodeid(none)]),
2244 b(integer(2),integer,[nodeid(none)])),integer,[contains_wd_condition,nodeid(none)]),
2245 b(integer(1),integer,[nodeid(none)])),pred,
2246 [contains_wd_condition,nodeid(none)])),pred,[contains_wd_condition,nodeid(none)])),
2247 set(integer),[contains_wd_condition,nodeid(none)])),
2248 pred,[contains_wd_condition,nodeid(none)]).
2249
2250 :- assert_must_succeed((bsyntaxtree:exists_ast(A), rename_bt(A,[rename(x,xx)],RA), RA==A )).
2251 :- assert_must_succeed((bsyntaxtree:exists_ast(A), rename_bt(A,[rename(r,v)],RA),
2252 translate:translate_bexpression(RA,TR), TR='v = {x|x : 1 .. y & x mod 2 = 1}' )).
2253 :- assert_must_succeed((gensym:reset_gensym, bsyntaxtree:exists_ast(A), rename_bt(A,[rename(y,x)],RA), RA \= A,
2254 translate:translate_bexpression(RA,TR),
2255 TR = 'r = {`__FRESH____1`|`__FRESH____1` : 1 .. x & `__FRESH____1` mod 2 = 1}' )).
2256
2257 % a simplified version of replace_ids_by_exprs, which assumes target of renamings are variables
2258 rename_bt(Expr,[],Res) :- !,Res=Expr.
2259 rename_bt(OExpr,Renamings,NExpr) :-
2260 create_texpr(Old,Type,OInfo,OExpr),
2261 create_texpr(New,Type,NInfo,NExpr),
2262 rename_in_infos(OInfo,Renamings,NInfo),
2263 rename_bt2(Old,Renamings,New).
2264 rename_bt2(identifier(Old),Renamings,identifier(New)) :-
2265 !, rename_id(Old,Renamings,New).
2266 rename_bt2(lazy_lookup_expr(Old),Renamings,lazy_lookup_expr(New)) :-
2267 !, rename_id(Old,Renamings,New).
2268 rename_bt2(lazy_lookup_pred(Old),Renamings,lazy_lookup_pred(New)) :-
2269 !, rename_id(Old,Renamings,New).
2270 rename_bt2(OExpr,Renamings,NExpr) :-
2271 syntaxtransformation(OExpr,Subs,TNames,NSubs,NExpr),
2272 get_texpr_exprs(TNames,Names),
2273 remove_renamings(Names,Renamings,NRenamings),
2274 rename_bt_l(Subs,NRenamings,NSubs).
2275 rename_bt_l([],_,[]).
2276 rename_bt_l([Old|ORest],Renamings,[New|NRest]) :-
2277 rename_bt(Old,Renamings,New),
2278 rename_bt_l(ORest,Renamings,NRest).
2279
2280 remove_renamings([],Renamings,Renamings).
2281 remove_renamings([identifier(Name)|Rest],Old,New) :-
2282 ? ( select(rename(Name,_),Old,Inter1) -> true % Name no longer visible to renaming
2283 ; Old = Inter1),
2284 (member(rename(_OldName,Name),Inter1) ->
2285 gensym('__FRESH__',FRESHID),
2286 %print(variable_capture_in_rename(Name,from(OldName),FRESHID)),nl,
2287 Inter2 = [rename(Name,FRESHID)|Inter1]
2288 ; Inter2 = Inter1),
2289 remove_renamings(Rest,Inter2,New).
2290
2291 rename_in_infos(Old,Renamings,New) :-
2292 ( has_info_to_rename(Old) ->
2293 maplist(rename_in_infos2(Renamings),Old,New)
2294 ;
2295 Old = New).
2296 rename_in_infos2(Renamings,OInfo,NInfo) :-
2297 ( infos_to_rename(OInfo,OIds,SortedNIds,NInfo) ->
2298 rename_ids(OIds,Renamings,NIds),
2299 sort(NIds,SortedNIds)
2300 ;
2301 OInfo = NInfo).
2302
2303 rename_ids([],_,[]).
2304 rename_ids([OId|Orest],Renamings,[NId|Nrest]) :-
2305 rename_id(OId,Renamings,NId),
2306 rename_ids(Orest,Renamings,Nrest).
2307 rename_id(Old,Renamings,New) :-
2308 ( memberchk(rename(Old,New),Renamings) -> true % we could use ord_member if we sort !
2309 ; Old=New).
2310
2311 has_info_to_rename(Infos) :-
2312 ? member(I,Infos),infos_to_rename(I,_,_,_),!.
2313
2314 infos_to_rename(modifies(O),O,N,modifies(N)).
2315 infos_to_rename(reads(O),O,N,reads(N)).
2316 infos_to_rename(non_det_modifies(O),O,N,non_det_modifies(N)).
2317 infos_to_rename(modifies_locals(O),O,N,modifies_locals(N)).
2318 infos_to_rename(reads_locals(O),O,N,reads_locals(N)).
2319 infos_to_rename(used_ids(O),O,N,used_ids(N)).
2320 %infos_to_rename(lambda_result(O),[O],[N],lambda_result(N)). % whould we no longer assume that we have lambda result, as predicate has possibly changed!?
2321
2322
2323 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
2324 % remove type information for transformations
2325
2326 remove_bt(b(Expr,Type,Infos),Expr,NExpr,b(NExpr,Type,Infos)).
2327
2328 remove_bt_and_used_ids(b(OldExpr,T,Infos),OldExpr,NewExpr,b(NewExpr,T,NewInfos)) :-
2329 delete(Infos,used_ids(_),NewInfos). % invalidate used_ids info
2330
2331 %remove_bt_l([],[],[],[]).
2332 %remove_bt_l([OT|OTRest],[O|ORest],[N|NRest],[NT|NTRest]) :-
2333 % remove_bt(OT,O,N,NT),
2334 % remove_bt_l(OTRest,ORest,NRest,NTRest).
2335
2336 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
2337 % traversations
2338 % Takes a predicate or expression or substitution and extracts:
2339 % the expression itself Expr, its type Type, the syntaxnode information Infos
2340 % + the subexpressions as a list Subs and the local identifiers declared
2341 syntaxtraversion(b(Expr,Type,Infos),Expr,Type,Infos,Subs,Names) :- !,
2342 safe_syntaxelement(Expr,Subs,Names,_,_).
2343 syntaxtraversion(IExpr,Expr,Type,Infos,Subs,Names) :-
2344 add_internal_error('Not properly wrapped', syntaxtraversion(IExpr,Expr,Type,Infos,Subs,Names)),
2345 fail.
2346
2347
2348 map_over_full_bexpr_no_fail(P,BExpr) :-
2349 syntaxtraversion(BExpr,Expr,_,_,Subs,_TNames),
2350 call(P,Expr), % the predicate should not fail
2351 (Subs=[] -> true ; maplist(map_over_full_bexpr_no_fail(P),Subs)).
2352
2353 map_over_bexpr(P,BExpr) :-
2354 syntaxtraversion(BExpr,Expr,_,_,Subs,_TNames),
2355 (call(P,Expr) % should probably fail so that by backtrack we recurse
2356 ;
2357 member(Sub,Subs), map_over_bexpr(P,Sub)
2358 ).
2359 % same as above but gets typed expressions:
2360 map_over_typed_bexpr(P,BExpr) :-
2361 syntaxtraversion(BExpr,_Expr,_,_,Subs,_TNames),
2362 (call(P,BExpr)
2363 ;
2364 ? member(Sub,Subs), map_over_typed_bexpr(P,Sub)
2365 ).
2366 % same as above but returns value:
2367 map_over_typed_bexpr(P,BExpr,Result) :-
2368 syntaxtraversion(BExpr,_Expr,_,_,Subs,_TNames),
2369 (call(P,BExpr,Result)
2370 ;
2371 ? member(Sub,Subs), map_over_typed_bexpr(P,Sub,Result)
2372 ).
2373 % this one gets TNames (locally introduced variables as parameter)
2374 map_over_typed_bexpr_with_names(P,BExpr) :-
2375 syntaxtraversion(BExpr,_Expr,_,_,Subs,TNames),
2376 (call(P,BExpr,TNames)
2377 ;
2378 member(Sub,Subs), map_over_typed_bexpr_with_names(P,Sub)
2379 ).
2380
2381 % same as map_over_expr but provides an accumulator passed top-down to children; needs to be used by failure driven loop
2382
2383 map_over_bexpr_top_down_acc(P,BExpr,TDAcc) :-
2384 syntaxtraversion(BExpr,Expr,_,_,Subs,_TNames),
2385 (call(P,Expr,TDAcc,NewAcc)
2386 -> member(Sub,Subs), map_over_bexpr_top_down_acc(P,Sub,NewAcc)
2387 ; member(Sub,Subs), map_over_bexpr_top_down_acc(P,Sub,TDAcc)
2388 ).
2389 % now a version which gets the typed predicate as argument
2390
2391 map_over_typed_bexpr_top_down_acc(P,BExpr,TDAcc) :-
2392 syntaxtraversion(BExpr,_Expr,_,_,Subs,_TNames),
2393 (call(P,BExpr,TDAcc,NewAcc)
2394 -> member(Sub,Subs), map_over_typed_bexpr_top_down_acc(P,Sub,NewAcc)
2395 ; member(Sub,Subs), map_over_typed_bexpr_top_down_acc(P,Sub,TDAcc)
2396 ).
2397
2398 % predicate P has 3 arguments: (Expr,ValueSoFar,NewValue)
2399 reduce_over_bexpr(P,BExpr,InitialValue,ResultValue) :-
2400 syntaxtraversion(BExpr,Expr,_,_,Subs,_TNames),
2401 call(P,Expr,InitialValue,I1), % print(reduce(P,Expr,InitialValue,I1)),nl,
2402 scanlist(reduce_over_bexpr(P),Subs,I1,ResultValue).
2403
2404 % apply a predicate over a syntax tree (bottom-up)
2405
2406 transform_bexpr(Pred,b(Expr,Type,Info),NewBExpr) :- !,
2407 syntaxtransformation(Expr,Subs,_Names,NSubs,NewExpr1),
2408 l_transform_bexpr(Subs,Pred,NSubs),
2409 (call(Pred,b(NewExpr1,Type,Info),NewBExpr) -> true ; NewBExpr = b(NewExpr1,Type,Info)).
2410 transform_bexpr(Pred,Expr,NewBExpr) :-
2411 add_internal_error('Expression not properly wrapped:',transform_bexpr(Pred,Expr,NewBExpr)),
2412 fail.
2413
2414 l_transform_bexpr([],_,[]).
2415 l_transform_bexpr([SubH|T],Pred,[TSubH|TT]) :-
2416 transform_bexpr(Pred,SubH,TSubH),
2417 l_transform_bexpr(T,Pred,TT).
2418
2419 % apply a predicate over a syntax tree (bottom-up), and provide scoping info about local ids
2420
2421 transform_bexpr_with_scoping(Pred,BExpr,NewBExpr) :-
2422 transform_bexpr_with_scoping2(Pred,BExpr,NewBExpr,[]).
2423 transform_bexpr_with_scoping2(Pred,b(Expr,Type,Info),NewBExpr,LocalIds) :-
2424 syntaxtransformation(Expr,Subs,Names,NSubs,NewExpr1),
2425 get_texpr_ids(Names,QuantifiedNewIds), list_to_ord_set(QuantifiedNewIds,SQuantifiedNewIds),
2426 ord_union(LocalIds,SQuantifiedNewIds,NewLocalIds),
2427 l_transform_bexpr_with_scoping(Subs,Pred,NSubs,NewLocalIds),
2428 (call(Pred,b(NewExpr1,Type,Info),NewBExpr,LocalIds) -> true ; NewBExpr = b(NewExpr1,Type,Info)).
2429
2430 l_transform_bexpr_with_scoping([],_,[],_).
2431 l_transform_bexpr_with_scoping([SubH|T],Pred,[TSubH|TT],LocalIds) :-
2432 transform_bexpr_with_scoping2(Pred,SubH,TSubH,LocalIds),
2433 l_transform_bexpr_with_scoping(T,Pred,TT,LocalIds).
2434
2435 % transform a predicate top-down with scoping infos
2436 % if Pred succeeds the top-down traversal stops
2437 transform_bexpr_td_with_scoping(Pred,BExpr,NewBExpr) :-
2438 transform_bexpr_td_with_scoping2(Pred,BExpr,NewBExpr,[]).
2439 transform_bexpr_td_with_scoping2(Pred,b(Expr,Type,Info),b(NewExpr1,Type,Info),LocalIds) :-
2440 ? (call(Pred,Expr,NewExpr1,LocalIds)
2441 -> true
2442 ; syntaxtransformation(Expr,Subs,Names,NSubs,NewExpr1),
2443 get_texpr_ids(Names,QuantifiedNewIds), list_to_ord_set(QuantifiedNewIds,SQuantifiedNewIds),
2444 ord_union(LocalIds,SQuantifiedNewIds,NewLocalIds),
2445 l_transform_bexpr_td_with_scoping(Subs,Pred,NSubs,NewLocalIds)
2446 ).
2447
2448 l_transform_bexpr_td_with_scoping([],_,[],_).
2449 l_transform_bexpr_td_with_scoping([SubH|T],Pred,[TSubH|TT],LocalIds) :-
2450 transform_bexpr_td_with_scoping2(Pred,SubH,TSubH,LocalIds),
2451 l_transform_bexpr_td_with_scoping(T,Pred,TT,LocalIds).
2452
2453
2454 % apply a predicate over a syntax tree (bottom-up) with Accumulator result
2455 % Accumulator is constructed bottom up; Pred receives *all* accumulators of sub expressions
2456
2457 transform_bexpr_with_bup_accs(Pred,b(Expr,Type,Info),NewBExpr,EmptyAcc,Acc) :-
2458 syntaxtransformation(Expr,Subs,_Names,NSubs,NewExpr1),
2459 l_transform_bexpr_with_bup_accs(Subs,Pred,NSubs,EmptyAcc,SubAccs),
2460 (call(Pred,b(NewExpr1,Type,Info),NewBExpr,SubAccs,Acc) -> true
2461 ; NewBExpr = b(NewExpr1,Type,Info), Acc = EmptyAcc).
2462
2463 l_transform_bexpr_with_bup_accs([],_,[],_,[]).
2464 l_transform_bexpr_with_bup_accs([SubH|T],Pred,[TSubH|TT],EmptyAcc,[Acc1|RestAcc]) :-
2465 transform_bexpr_with_bup_accs(Pred,SubH,TSubH,EmptyAcc,Acc1),
2466 l_transform_bexpr_with_bup_accs(T,Pred,TT,EmptyAcc,RestAcc).
2467
2468 % apply a predicate over a syntax tree (bottom-up) with Accumulator result
2469 % a single Accumulator is passed along
2470
2471 transform_bexpr_with_acc(_Pred,E,NewBExpr,InAcc,Acc) :- var(E),!,
2472 NewBExpr=E, Acc=InAcc.
2473 transform_bexpr_with_acc(Pred,b(Expr,Type,Info),NewBExpr,InAcc,Acc) :-
2474 syntaxtransformation(Expr,Subs,_Names,NSubs,NewExpr1),
2475 l_transform_bexpr_with_acc(Subs,Pred,NSubs,InAcc,SubAcc),
2476 (call(Pred,b(NewExpr1,Type,Info),NewBExpr,SubAcc,Acc) -> true
2477 ; NewBExpr = b(NewExpr1,Type,Info), Acc = SubAcc).
2478
2479 l_transform_bexpr_with_acc([],_,[],Acc,Acc).
2480 l_transform_bexpr_with_acc([SubH|T],Pred,[TSubH|TT],InAcc,ResAcc) :-
2481 transform_bexpr_with_acc(Pred,SubH,TSubH,InAcc,Acc1),
2482 l_transform_bexpr_with_acc(T,Pred,TT,Acc1,ResAcc).
2483
2484 % a non-deterministic version of this
2485 non_det_transform_bexpr_with_acc(_Pred,E,NewBExpr,InAcc,Acc) :- var(E),!,
2486 NewBExpr=E, Acc=InAcc.
2487 non_det_transform_bexpr_with_acc(Pred,b(Expr,Type,Info),NewBExpr,InAcc,Acc) :-
2488 syntaxtransformation(Expr,Subs,_Names,NSubs,NewExpr1),
2489 l_nd_transform_bexpr_with_acc(Subs,Pred,NSubs,InAcc,SubAcc),
2490 if(call(Pred,b(NewExpr1,Type,Info),NewBExpr,SubAcc,Acc),
2491 true,
2492 (NewBExpr = b(NewExpr1,Type,Info), Acc = SubAcc)).
2493
2494 l_nd_transform_bexpr_with_acc([],_,[],Acc,Acc).
2495 l_nd_transform_bexpr_with_acc([SubH|T],Pred,[TSubH|TT],InAcc,ResAcc) :-
2496 non_det_transform_bexpr_with_acc(Pred,SubH,TSubH,InAcc,Acc1),
2497 l_nd_transform_bexpr_with_acc(T,Pred,TT,Acc1,ResAcc).
2498
2499
2500 % -------------------------
2501
2502 min_max_integer_value_used(BExpr,Min,Max) :-
2503 min_max_integer_value_used(BExpr,none,none,Min,Max).
2504 min_max_integer_value_used(BExpr,IMin,IMax,Min,Max) :-
2505 reduce_over_bexpr(min_max_aux,BExpr,minmax(IMin,IMax),minmax(Min,Max)).
2506
2507 min_max_aux(sequence_extension(L),minmax(Min,Max),minmax(NMin,NMax)) :- !,
2508 length(L,Len), % we use implicitly numbers from 1..Len
2509 (number(Min),1>Min -> NMin=Min ; NMin=1),
2510 (number(Max),Len<Max -> NMax=Max ; NMax=Len).
2511 min_max_aux(integer(N),minmax(Min,Max),minmax(NMin,NMax)) :- !,
2512 (number(Min),N>Min -> NMin=Min ; NMin=N),
2513 (number(Max),N<Max -> NMax=Max ; NMax=N).
2514 min_max_aux(_,V,V).
2515
2516 % check if a B expression uses something like NAT,NAT1,INT, MAXINT or MININT.
2517 uses_implementable_integers(BExpr) :-
2518 map_over_bexpr(uses_implementable_integers_aux,BExpr).
2519
2520 uses_implementable_integers_aux(maxint).
2521 uses_implementable_integers_aux(minint).
2522 uses_implementable_integers_aux(integer_set(X)) :-
2523 (X='NAT1' ; X='NAT' ; X='INT').
2524
2525 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
2526 % some checks
2527 check_if_typed_predicate(b(Pred,X,_)) :- ground(X), X=pred, % at runtime there can be value(X) with variables inside !
2528 syntaxelement(Pred,_,_,_,_,TypePred), (TypePred=pred -> true ; TypePred = pred/only_typecheck).
2529 check_if_typed_expression(b(Expr,Type,_)) :-
2530 syntaxelement(Expr,_,_,_,_,TypeExpr),
2531 (TypeExpr=expr -> true ; TypeExpr = expr/only_typecheck),
2532 Type \== pred, Type \== subst, ground(Type).
2533 check_if_typed_substitution(b(Subst,X,_)) :- ground(X), X=subst,
2534 syntaxelement(Subst,_,_,_,_,subst).
2535
2536 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
2537 % transformations
2538
2539 syntaxtransformation(Expr,Subs,Names,NSubs,NExpr) :-
2540 functor(Expr,F,Arity),
2541 functor(NExpr,F,Arity),
2542 safe_syntaxelement(Expr,Subs,Names,Lists,Constant),
2543 all_same_length(Lists,NLists),
2544 syntaxelement(NExpr,NSubs,_,NLists,Constant,_).
2545 % a faster non-backtracking version:
2546 syntaxtransformation_det(Expr,Subs,Names,NSubs,NExpr) :-
2547 functor(Expr,F,Arity),
2548 functor(NExpr,F,Arity),
2549 safe_syntaxelement_det(Expr,Subs,Names,Lists,Constant),
2550 all_same_length(Lists,NLists),
2551 syntaxelement(NExpr,NSubs,_,NLists,Constant,_).
2552
2553
2554 safe_syntaxelement(Expr,Subs,Names,Lists,Constant) :-
2555 ( syntaxelement(Expr,SubsX,NamesX,Lists,ConstantX,_) ->
2556 Subs=SubsX, Names=NamesX, Constant=ConstantX
2557 %(Subs,Names,Constant)=(SubsX,NamesX,ConstantX)
2558 ;
2559 functor(Expr,F,Arity),
2560 add_error_fail(bsyntaxtree,'Uncovered syntax element: ', F/Arity)
2561 ).
2562 % a faster non-backtracking version of safe_syntaxelement, assuming Subs, Names, ... are fresh vars
2563 safe_syntaxelement_det(Expr,Subs,Names,Lists,Constant) :-
2564 (syntaxelement(Expr,Subs,Names,Lists,Constant,_) -> true
2565 ; functor(Expr,F,Arity),
2566 add_error_fail(bsyntaxtree,'Uncovered syntax element: ', F/Arity)).
2567
2568 is_subst_syntaxelement(Subst) :-
2569 syntaxelement(Subst,_,_,_,_,subst).
2570
2571 % check if we have a syntax node without parameters
2572 is_syntax_constant(Expr) :- atom(Expr), syntaxelement(Expr,_,_,_,_,_).
2573
2574 % syntaxelement(Expr,SubExprs,Identifiers,Lists,Constant,Type):
2575 % Expr: the expression itself
2576 % SubExprs: a list of sub-expressions
2577 % Identifiers: a list of identifiers that are newly introduced (e.g. by a quantifier)
2578 % Lists: A list of lists in the expression, to prevent infinite loops when having variable parts
2579 % Constant: A part of the expression that is not a sub-expression (e.g. the number in integer(...))
2580 % Type: Fundamental type of the element (predicate, expression, etc)
2581
2582 % predicates
2583 syntaxelement(truth, [], [], [], [], pred).
2584 syntaxelement(falsity, [], [], [], [], pred).
2585 syntaxelement(unknown_truth_value(Msg),[], [], [], Msg, pred). % artificial, e.g., created by well_def_analyser
2586 syntaxelement(conjunct(A,B), [A,B],[], [], [], pred).
2587 %syntaxelement(conjunct(As), As, [], [], [], pred). % TO DO: support associative version of conjunct
2588 syntaxelement(negation(A), [A], [], [], [], pred).
2589 syntaxelement(disjunct(A,B), [A,B],[], [], [], pred).
2590 syntaxelement(implication(A,B), [A,B],[], [], [], pred).
2591 syntaxelement(equivalence(A,B), [A,B],[], [], [], pred).
2592 syntaxelement(equal(A,B), [A,B],[], [], [], pred).
2593 syntaxelement(not_equal(A,B), [A,B],[], [], [], pred).
2594 syntaxelement(member(A,B), [A,B],[], [], [], pred).
2595 syntaxelement(not_member(A,B), [A,B],[], [], [], pred).
2596 syntaxelement(subset(A,B), [A,B],[], [], [], pred).
2597 syntaxelement(subset_strict(A,B), [A,B],[], [], [], pred).
2598 syntaxelement(not_subset(A,B), [A,B],[], [], [], pred).
2599 syntaxelement(not_subset_strict(A,B),[A,B],[], [], [], pred).
2600 syntaxelement(less_equal(A,B), [A,B],[], [], [], pred).
2601 syntaxelement(less(A,B), [A,B],[], [], [], pred).
2602 syntaxelement(less_equal_real(A,B), [A,B],[], [], [], pred).
2603 syntaxelement(less_real(A,B), [A,B],[], [], [], pred).
2604 syntaxelement(greater_equal(A,B), [A,B],[], [], [], pred).
2605 syntaxelement(greater(A,B), [A,B],[], [], [], pred).
2606 syntaxelement(forall(Ids,D,P), [D,P|Ids],Ids,[Ids], [], pred).
2607 syntaxelement(exists(Ids,P), [P|Ids], Ids,[Ids], [], pred).
2608 syntaxelement(finite(A), [A], [], [], [], pred/only_typecheck).
2609 syntaxelement(partition(S,Es), [S|Es],[],[Es],[],pred).
2610 syntaxelement(kodkod(PId,Ids), Ids,[],[Ids],PId, pred).
2611 syntaxelement(external_pred_call(F,Args),Args,[],[Args],F,pred).
2612
2613 % expressions
2614 syntaxelement(value(V), [], [], [], V, expr).
2615 syntaxelement(operation_call_in_expr(Id,As), As, [], [As], Id, expr). % Do not treat Id as a sub-expression for find_identifier_uses, ...
2616 %syntaxelement(operation_call_in_expr(Id,As), [Id|As], [], [As], [], expr). % was like this, but changed to avoid op(.) ids in find_identifier_uses
2617 syntaxelement(boolean_true, [], [], [], [], expr).
2618 syntaxelement(boolean_false, [], [], [], [], expr).
2619 syntaxelement(max_int, [], [], [], [], expr).
2620 syntaxelement(min_int, [], [], [], [], expr).
2621 syntaxelement(empty_set, [], [], [], [], expr).
2622 syntaxelement(bool_set, [], [], [], [], expr).
2623 syntaxelement(float_set, [], [], [], [], expr).
2624 syntaxelement(real(I), [], [], [], I, expr).
2625 syntaxelement(real_set, [], [], [], [], expr).
2626 syntaxelement(string_set, [], [], [], [], expr).
2627 syntaxelement(convert_bool(A), [A], [], [], [], expr).
2628 syntaxelement(convert_real(A), [A], [], [], [], expr).
2629 syntaxelement(convert_int_floor(A), [A], [], [], [], expr).
2630 syntaxelement(convert_int_ceiling(A), [A], [], [], [], expr).
2631 syntaxelement(add(A,B), [A,B],[], [], [], expr).
2632 syntaxelement(add_real(A,B), [A,B],[], [], [], expr).
2633 syntaxelement(minus(A,B), [A,B],[], [], [], expr).
2634 syntaxelement(minus_real(A,B), [A,B],[], [], [], expr).
2635 syntaxelement(minus_or_set_subtract(A,B),[A,B],[], [], [], expr/only_typecheck).
2636 syntaxelement(unary_minus(A), [A], [], [], [], expr).
2637 syntaxelement(unary_minus_real(A), [A], [], [], [], expr).
2638 syntaxelement(multiplication(A,B), [A,B],[], [], [], expr).
2639 syntaxelement(multiplication_real(A,B),[A,B],[], [], [], expr).
2640 syntaxelement(mult_or_cart(A,B), [A,B],[], [], [], expr/only_typecheck).
2641 syntaxelement(cartesian_product(A,B), [A,B],[], [], [], expr).
2642 syntaxelement(div(A,B), [A,B],[], [], [], expr).
2643 syntaxelement(div_real(A,B), [A,B],[], [], [], expr).
2644 syntaxelement(floored_div(A,B), [A,B],[], [], [], expr).
2645 syntaxelement(modulo(A,B), [A,B],[], [], [], expr).
2646 syntaxelement(power_of(A,B), [A,B],[], [], [], expr).
2647 syntaxelement(power_of_real(A,B), [A,B],[], [], [], expr).
2648 syntaxelement(successor, [], [], [], [], expr).
2649 syntaxelement(predecessor, [], [], [], [], expr).
2650 syntaxelement(max(A), [A], [], [], [], expr).
2651 syntaxelement(max_real(A), [A], [], [], [], expr).
2652 syntaxelement(min(A), [A], [], [], [], expr).
2653 syntaxelement(min_real(A), [A], [], [], [], expr).
2654 syntaxelement(card(A), [A], [], [], [], expr).
2655 syntaxelement(couple(A,B), [A,B],[], [], [], expr).
2656 syntaxelement(pow_subset(A), [A], [], [], [], expr).
2657 syntaxelement(pow1_subset(A), [A], [], [], [], expr).
2658 syntaxelement(fin_subset(A), [A], [], [], [], expr).
2659 syntaxelement(fin1_subset(A), [A], [], [], [], expr).
2660 syntaxelement(interval(A,B), [A,B],[], [], [], expr).
2661 syntaxelement(union(A,B), [A,B],[], [], [], expr).
2662 syntaxelement(intersection(A,B), [A,B],[], [], [], expr).
2663 syntaxelement(set_subtraction(A,B), [A,B],[], [], [], expr).
2664 syntaxelement(general_union(A), [A], [], [], [], expr).
2665 syntaxelement(general_intersection(A), [A] , [], [], [], expr).
2666 syntaxelement(relations(A,B), [A,B],[], [], [], expr).
2667 syntaxelement(identity(A), [A], [], [], [], expr).
2668 syntaxelement(event_b_identity, [], [], [], [], expr). % for Rodin 1.0, TO DO: Daniel please check
2669 syntaxelement(reverse(A), [A], [], [], [], expr).
2670 syntaxelement(first_projection(A,B), [A,B],[], [], [], expr/only_typecheck).
2671 syntaxelement(first_of_pair(A), [A], [], [], [], expr).
2672 syntaxelement(event_b_first_projection(A),[A], [], [], [], expr/only_typecheck).
2673 syntaxelement(event_b_first_projection_v2,[], [], [], [], expr/only_typecheck). % for Rodin 1.0, TO DO: Daniel please check
2674 syntaxelement(second_projection(A,B), [A,B],[], [], [], expr/only_typecheck).
2675 syntaxelement(event_b_second_projection_v2,[], [], [], [], expr/only_typecheck). % for Rodin 1.0, TO DO: Daniel please check
2676 syntaxelement(second_of_pair(A), [A], [], [], [], expr).
2677 syntaxelement(event_b_second_projection(A),[A], [], [], [], expr/only_typecheck).
2678 syntaxelement(composition(A,B), [A,B],[], [], [], expr).
2679 syntaxelement(ring(A,B), [A,B],[], [], [], expr/only_typecheck).
2680 syntaxelement(direct_product(A,B), [A,B],[], [], [], expr).
2681 syntaxelement(parallel_product(A,B), [A,B],[], [], [], expr).
2682 syntaxelement(trans_function(A), [A], [], [], [], expr).
2683 syntaxelement(trans_relation(A), [A], [], [], [], expr).
2684 syntaxelement(iteration(A,B), [A,B],[], [], [], expr).
2685 syntaxelement(reflexive_closure(A), [A], [], [], [], expr).
2686 syntaxelement(closure(A), [A], [], [], [], expr).
2687 syntaxelement(domain(A), [A], [], [], [], expr).
2688 syntaxelement(range(A), [A], [], [], [], expr).
2689 syntaxelement(image(A,B), [A,B],[], [], [], expr).
2690 syntaxelement(domain_restriction(A,B), [A,B],[], [], [], expr).
2691 syntaxelement(domain_subtraction(A,B), [A,B],[], [], [], expr).
2692 syntaxelement(range_restriction(A,B), [A,B],[], [], [], expr).
2693 syntaxelement(range_subtraction(A,B), [A,B],[], [], [], expr).
2694 syntaxelement(overwrite(A,B), [A,B],[], [], [], expr).
2695 syntaxelement(partial_function(A,B), [A,B],[], [], [], expr).
2696 syntaxelement(total_function(A,B), [A,B],[], [], [], expr).
2697 syntaxelement(partial_injection(A,B), [A,B],[], [], [], expr).
2698 syntaxelement(total_injection(A,B), [A,B],[], [], [], expr).
2699 syntaxelement(partial_surjection(A,B), [A,B],[], [], [], expr).
2700 syntaxelement(total_surjection(A,B), [A,B],[], [], [], expr).
2701 syntaxelement(total_bijection(A,B), [A,B],[], [], [], expr).
2702 syntaxelement(partial_bijection(A,B), [A,B],[], [], [], expr).
2703 syntaxelement(total_relation(A,B), [A,B],[], [], [], expr).
2704 syntaxelement(surjection_relation(A,B),[A,B],[], [], [], expr).
2705 syntaxelement(total_surjection_relation(A,B),[A,B],[], [], [], expr).
2706 syntaxelement(seq(A), [A], [], [], [], expr).
2707 syntaxelement(seq1(A), [A], [], [], [], expr).
2708 syntaxelement(iseq(A), [A], [], [], [], expr).
2709 syntaxelement(iseq1(A), [A], [], [], [], expr).
2710 syntaxelement(perm(A), [A], [], [], [], expr).
2711 syntaxelement(empty_sequence, [], [], [], [], expr).
2712 syntaxelement(size(A), [A], [], [], [], expr).
2713 syntaxelement(first(A), [A], [], [], [], expr).
2714 syntaxelement(last(A), [A], [], [], [], expr).
2715 syntaxelement(front(A), [A], [], [], [], expr).
2716 syntaxelement(tail(A), [A], [], [], [], expr).
2717 syntaxelement(rev(A), [A], [], [], [], expr).
2718 syntaxelement(concat(A,B), [A,B],[], [], [], expr).
2719 syntaxelement(insert_front(A,B), [A,B],[], [], [], expr).
2720 syntaxelement(insert_tail(A,B), [A,B],[], [], [], expr).
2721 syntaxelement(restrict_front(A,B), [A,B],[], [], [], expr).
2722 syntaxelement(restrict_tail(A,B), [A,B],[], [], [], expr).
2723 syntaxelement(general_concat(A), [A], [], [], [], expr).
2724 syntaxelement(function(A,B), [A,B],[], [], [], expr).
2725 syntaxelement(external_function_call(F,Args),Args,[],[Args],F,expr).
2726 syntaxelement(identifier(I), [], [], [], I, expr).
2727 syntaxelement(lazy_lookup_expr(I), [], [], [], I, expr).
2728 syntaxelement(lazy_lookup_pred(I), [], [], [], I, pred).
2729 syntaxelement(integer(I), [], [], [], I, expr).
2730 syntaxelement(integer_set(T), [], [], [], T, expr).
2731 syntaxelement(string(S), [], [], [], S, expr).
2732 syntaxelement(set_extension(L), L, [], [L], [], expr).
2733 syntaxelement(sequence_extension(L), L, [], [L], [], expr).
2734 syntaxelement(comprehension_set(Ids,P),[P|Ids], Ids,[Ids], [], expr).
2735 syntaxelement(event_b_comprehension_set(Ids,E,P),[E,P|Ids], Ids,[Ids], [], expr/only_typecheck).
2736 syntaxelement(lambda(Ids,P,E), [P,E|Ids],Ids,[Ids], [], expr).
2737 syntaxelement(general_sum(Ids,P,E), [P,E|Ids],Ids,[Ids], [], expr).
2738 syntaxelement(general_product(Ids,P,E), [P,E|Ids],Ids,[Ids], [], expr).
2739 syntaxelement(quantified_union(Ids,P,E), [P,E|Ids],Ids,[Ids], [], expr).
2740 syntaxelement(quantified_intersection(Ids,P,E), [P,E|Ids],Ids,[Ids], [], expr).
2741 syntaxelement(struct(Rec), [Rec], [], [], [], expr).
2742 syntaxelement(rec(Fields), FContent, [], [FContent], FNames, expr) :- syntaxfields(Fields,FContent, FNames).
2743 syntaxelement(record_field(R,I), [R], [], [], I, expr).
2744 syntaxelement(assertion_expression(Cond,ErrMsg,Expr), [Cond,Expr], [], [], ErrMsg, expr).
2745 syntaxelement(typeset, [], [], [], [], expr/only_typecheck).
2746
2747 syntaxelement(tree(A), [A], [], [], [], expr).
2748 syntaxelement(btree(A), [A], [], [], [], expr).
2749 syntaxelement(const(A,B), [A,B],[], [], [], expr).
2750 syntaxelement(top(A), [A], [], [], [], expr).
2751 syntaxelement(sons(A), [A], [], [], [], expr).
2752 syntaxelement(prefix(A), [A], [], [], [], expr).
2753 syntaxelement(postfix(A), [A], [], [], [], expr).
2754 syntaxelement(sizet(A), [A], [], [], [], expr).
2755 syntaxelement(mirror(A), [A], [], [], [], expr).
2756 syntaxelement(rank(A,B), [A,B],[], [], [], expr).
2757 syntaxelement(father(A,B), [A,B],[], [], [], expr).
2758 syntaxelement(son(A,B,C), [A,B,C],[], [], [], expr).
2759 syntaxelement(subtree(A,B), [A,B],[], [], [], expr).
2760 syntaxelement(arity(A,B), [A,B],[], [], [], expr).
2761 syntaxelement(bin(A), [A],[], [], [], expr).
2762 syntaxelement(bin(A,B,C), [A,B,C],[], [], [], expr).
2763 syntaxelement(infix(A), [A], [], [], [], expr).
2764 syntaxelement(left(A), [A], [], [], [], expr).
2765 syntaxelement(right(A), [A], [], [], [], expr).
2766
2767 % substitutions
2768 syntaxelement(skip, [], [], [], [], subst).
2769 syntaxelement(precondition(A,B), [A,B],[], [], [], subst).
2770 syntaxelement(assertion(A,B), [A,B],[], [], [], subst).
2771 syntaxelement(witness_then(A,B), [A,B],[], [], [], subst).
2772 syntaxelement(if_elsif(A,B), [A,B],[], [], [], subst/elsif).
2773 syntaxelement(while(A,B,C,D), [A,B,C,D],[], [], [], subst).
2774 % used only internally in the interpreter, contains last value of variant:
2775 syntaxelement(while1(A,B,C,D,E), [A,B,C,D],[], [], E, subst).
2776 syntaxelement(select_when(A,B), [A,B],[], [], [], subst/when).
2777 syntaxelement(block(S),[S],[],[],[], subst/only_typecheck).
2778 syntaxelement(assign(Lhs,Rhs),Exprs,[],[Lhs,Rhs], [], subst) :- append(Lhs,Rhs,Exprs).
2779 syntaxelement(assign_single_id(Id,Rhs),[Id,Rhs],[],[], [], subst).
2780 syntaxelement(any(Ids,P,S),[P,S|Ids],Ids,[Ids], [], subst).
2781 syntaxelement(var(Ids,S), [S|Ids], Ids,[Ids], [], subst).
2782 syntaxelement(if(Ifs), Ifs, [], [Ifs], [], subst).
2783 syntaxelement(parallel(Ss), Ss, [], [Ss], [], subst).
2784 syntaxelement(sequence(Ss), Ss, [], [Ss], [], subst).
2785 syntaxelement(becomes_element_of(Ids,E), [E|Ids], [], [Ids], [], subst).
2786 syntaxelement(becomes_such(Ids,P), [P|Ids], [], [Ids], [], subst). % Ids are new value, Ids$0 is old value
2787 syntaxelement(evb2_becomes_such(Ids,P), [P|Ids], [], [Ids], [], subst/only_typecheck).
2788 syntaxelement(let(Ids,P,S), [P,S|Ids], Ids, [Ids], [], subst).
2789 syntaxelement(operation_call(Id,Rs,As), [Id|Exprs], [], [Rs,As], [], subst) :- append(Rs,As,Exprs).
2790 syntaxelement(case(E,Eithers,Else), [E,Else|Eithers], [], [Eithers], [], subst).
2791 syntaxelement(case_or(Es,S), [S|Es], [], [Es], [], subst/caseor).
2792 syntaxelement(choice(Ss), Ss, [], [Ss], [], subst).
2793 syntaxelement(select(Whens), Whens, [], [Whens], [], subst).
2794 syntaxelement(select(Whens,Else), [Else|Whens], [], [Whens], [], subst).
2795 syntaxelement(operation(I,Rs,As,B), [I,B|Ids], Ids, [Rs,As], [], subst) :- append(Rs,As,Ids).
2796 syntaxelement(external_subst_call(F,Args),Args,[],[Args],F,subst).
2797
2798 % elements of a VALUES clause
2799 syntaxelement(values_entry(I,E),[I,E],[],[],[],values_entry).
2800
2801 % syntax for Event-B events
2802 syntaxelement(rlevent(I,Sec,St,Ps,G,Ts,As,VWs,PWs,Ums,Rs), Subs, [], [Ps,Ts,As,VWs,PWs,Ums,Rs], [I,Sec], subst) :-
2803 append([[St],Ps,[G],Ts,As,VWs,PWs,Ums,Rs],Subs).
2804 syntaxelement(witness(I,P), [I,P], [], [], [], witness).
2805
2806 % extended syntax for Z
2807 syntaxelement(let_predicate(Ids,As,Pred), Exprs, Ids, [Ids,As], [], pred) :- append([Ids,As,[Pred]],Exprs).
2808 syntaxelement(let_expression(Ids,As,Expr), Exprs, Ids, [Ids,As], [], expr) :- append([Ids,As,[Expr]],Exprs).
2809 syntaxelement(let_expression_global(Ids,As,Expr), Exprs, Ids, [Ids,As], [], expr) :- % version used by b_compiler
2810 append([Ids,As,[Expr]],Exprs).
2811 syntaxelement(lazy_let_expr(TID,A,Expr), [TID, A, Expr], [TID], [[TID],[A]], [], expr).
2812 syntaxelement(lazy_let_pred(TID,A,Expr), [TID, A, Expr], [TID], [[TID],[A]], [], pred).
2813 syntaxelement(lazy_let_subst(TID,A,Expr), [TID, A, Expr], [TID], [[TID],[A]], [], subst).
2814 syntaxelement(if_then_else(If,Then,Else),[If,Then,Else], [], [], [], expr).
2815 syntaxelement(compaction(A), [A], [], [], [], expr).
2816 syntaxelement(mu(A), [A], [], [], [], expr).
2817 syntaxelement(bag_items(A), [A], [], [], [], expr).
2818
2819 syntaxelement(freetype_set(Id), [], [], [], Id, expr).
2820 syntaxelement(freetype_case(Type,Case,Expr), [Expr], [], [], [Type,Case], pred).
2821 syntaxelement(freetype_constructor(Type,Case,Expr), [Expr], [], [], [Type,Case], expr).
2822 syntaxelement(freetype_destructor(Type,Case,Expr), [Expr], [], [], [Type,Case], expr).
2823
2824 syntaxelement(ordinary, [], [], [], [], status).
2825 syntaxelement(anticipated(Variant), [Variant], [], [], [], status).
2826 syntaxelement(convergent(Variant), [Variant], [], [], [], status).
2827
2828 % Just one ID expected
2829 syntaxelement(recursive_let(Id,C),[Id,C],[Id],[],[], expr). % Note: Id is not really introduced !
2830
2831
2832 % fields of records
2833 %syntaxfields(Fields,C,_) :- var(Fields),var(C),var(N),!, add_internal_error('Illegal call: ',syntaxfields(Fields,C,N)),fail.
2834 syntaxfields([],[],[]).
2835 syntaxfields([field(N,C)|Rest],[C|CRest],[N|NRest]) :- syntaxfields(Rest,CRest,NRest).
2836
2837 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
2838 % helper for declaration of quantified identifiers
2839
2840 % has_declared_identifier/2 returns a list of identifiers which are declared in
2841 % this AST node. The main difference to the Names variable when doing a
2842 % syntaxtraversion/6 or similiar is that the identifiers are described by
2843 % predicates.
2844 has_declared_identifier(TExpr,Ids) :-
2845 get_texpr_expr(TExpr,Expr),
2846 ( default_declaration(Expr,_,Ids,_)
2847 ; non_default_declaration(Expr,Ids)).
2848
2849 add_declaration_for_identifier(b(Expr,Type,Infos),Decl,b(NExpr,Type,NewInfos)) :-
2850 %delete(Infos,used_ids(_),NewInfos), % we cannot
2851 ( default_declaration(Expr,Predicate,Ids,Constant) ->
2852 same_functor(Expr,NExpr),
2853 conjunct_predicates([Decl,Predicate],NPredicate),
2854 default_declaration(NExpr,NPredicate,Ids,Constant)
2855 ; non_default_declaration(Expr,Ids) ->
2856 add_non_default_declaration(Expr,Decl,NExpr)
2857 ),
2858 add_used_ids(Infos,Ids,Decl,NewInfos).
2859
2860 % add used ids of a predicate within quantification of Ids to current used_ids info; if it is there
2861 add_used_ids(Infos,Ids,Pred,NewInfos) :- update_used_ids(Infos,OldUsed,NewInfos,NewUsed),
2862 !, % a field needs updating
2863 find_identifier_uses(Pred,[],NewIds), get_texpr_ids(Ids,UnsortedIds),sort(UnsortedIds,SIds),
2864 ord_subtract(NewIds,SIds,NewIds2),
2865 ord_union(NewIds2,OldUsed,NewUsed).
2866 add_used_ids(I,_,_,I).
2867
2868 % just update used_ids field (e.g., when just computed to store it for later)
2869 update_used_ids(Infos,OldUsed,NewInfos,NewUsed) :- select(OldInfo,Infos,I1),
2870 used_ids_like_info(OldInfo,F,OldUsed),!,
2871 used_ids_like_info(NewInfo,F,NewUsed),NewInfos = [NewInfo|I1].
2872
2873 % info fields which contain used_ids information
2874 used_ids_like_info(used_ids(UsedIds),used_ids,UsedIds).
2875 used_ids_like_info(reads(UsedIds),reads,UsedIds).
2876
2877 :- use_module(probsrc(btypechecker), [prime_identifiers/2]).
2878
2879 % default_declaration(Expr,Predicate,Ids,Constant)
2880 default_declaration(forall(Ids,D,P),D,Ids,P).
2881 default_declaration(exists(Ids,P),P,Ids,[]).
2882 default_declaration(comprehension_set(Ids,P),P,Ids,[]).
2883 default_declaration(event_b_comprehension_set(Ids,E,P),P,Ids,E). % translated !?
2884 default_declaration(lambda(Ids,P,E),P,Ids,E).
2885 default_declaration(general_sum(Ids,P,E),P,Ids,E).
2886 default_declaration(general_product(Ids,P,E),P,Ids,E).
2887 default_declaration(quantified_union(Ids,P,E),P,Ids,E).
2888 default_declaration(quantified_intersection(Ids,P,E),P,Ids,E).
2889 default_declaration(any(Ids,P,S),P,Ids,S).
2890 default_declaration(becomes_such(Ids,P),P,Ids,[]).
2891 default_declaration(evb2_becomes_such(Ids,P),P,Primed,[]) :-
2892 nl,print(evb2(Ids,Primed)),nl,nl, % no longer used, as it is translated to becomes_such
2893 prime_identifiers(Ids,Primed).
2894 default_declaration(rlevent(I,Sec,St,Ps,G,Ts,As,VWs,PWs,Ums,Rs),G,Ps,
2895 [I,Sec,St,Ps,Ts,As,VWs,PWs,Ums,Rs]).
2896 default_declaration(let_predicate(Ids,Ps,Body),Ps,Ids,Body) :- print(let(Ids)),nl. % TODO: check format of Ps
2897 default_declaration(let_expression(Ids,Ps,Body),Ps,Ids,Body) :- print(let(Ids)),nl. % TODO: check format of Ps
2898 default_declaration(let_expression_global(Ids,Ps,Body),Ps,Ids,Body) :- print(let(Ids)),nl. % TODO: check format of Ps
2899 % TODO: lazy let ?
2900
2901 non_default_declaration(operation(_I,Rs,As,_TBody),Ids) :-
2902 append(Rs,As,Ids).
2903
2904 add_non_default_declaration(operation(I,Rs,As,TBody),Decl,operation(I,Rs,As,NTBody)) :-
2905 ( get_guard_and_copy(TBody,P,NP,NTBody) ->
2906 conjunct_predicates([Decl,P],NP)
2907 ; create_texpr(precondition(Decl,TBody),subst,[],NTBody)).
2908
2909 get_guard_and_copy(TBody,P,NP,NTBody) :- remove_bt(TBody,Body,NBody,NTBody),
2910 get_guard_copy2(Body,P,NP,NBody).
2911
2912 get_guard_copy2(precondition(P,S),P,NP,precondition(NP,S)).
2913 get_guard_copy2(rlevent(I,Sec,St,Ps, G,Ts,As,VWs,PWs,Ums,Rs), G, NG,
2914 rlevent(I,Sec,St,Ps,NG,Ts,As,VWs,PWs,Ums,Rs)).
2915
2916 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
2917 % pattern definitions (not yet finished)
2918
2919 bsyntax_pattern(Expr,TExpr) :-
2920 var(Expr),!,Expr=TExpr.
2921 bsyntax_pattern(-Expr,TExpr) :-
2922 !,remove_all_infos(Expr,TExpr).
2923 bsyntax_pattern(Expr,TExpr) :-
2924 functor(Expr,b,3),!,Expr=TExpr.
2925 bsyntax_pattern(Expr:Type/Info,TExpr) :-
2926 !,bsyntax_pattern2(Expr,Type,Info,TExpr).
2927 bsyntax_pattern(Expr:Type,TExpr) :-
2928 !,bsyntax_pattern2(Expr,Type,_Info,TExpr).
2929 bsyntax_pattern(Expr/Info,TExpr) :-
2930 !,bsyntax_pattern2(Expr,_Type,Info,TExpr).
2931 bsyntax_pattern(Expr,TExpr) :-
2932 !,bsyntax_pattern2(Expr,_Type,_Info,TExpr).
2933
2934 bsyntax_pattern2(Pattern,Type,Info,TExpr) :-
2935 functor(Pattern,Functor,Arity),
2936 functor(R,Functor,Arity),
2937 create_texpr(R,Type,Info,TExpr),
2938 syntaxelement(Pattern,PSubs,_,PLists,Const,EType),
2939 syntaxelement(R,RSubs,_,RLists,Const,EType),
2940 ( EType==pred -> Type=pred
2941 ; EType==subst -> Type=subst
2942 ; true),
2943 all_same_length(PLists,RLists),
2944 maplist(bsyntax_pattern,PSubs,RSubs).
2945
2946 all_same_length([],[]).
2947 all_same_length([A|Arest],[B|Brest]) :-
2948 ( var(A),var(B) ->
2949 add_error_fail(bsyntaxtree,'At least one list should contain nonvar elements for all_same_length',[A,B])
2950 ;
2951 same_length(A,B)),
2952 all_same_length(Arest,Brest).
2953
2954 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
2955 % strip an AST into a more compact form (without b/3 terms)
2956
2957 strip_and_norm_ast(TExpr,SNExpr) :-
2958 get_texpr_expr(TExpr,Expr),
2959 strip_and_norm_ast_aux(Expr,SNExpr).
2960
2961 :- use_module(tools,[safe_univ_no_cutoff/2]).
2962 strip_and_norm_ast_aux(Expr,Res) :-
2963 comm_assoc_subs(Expr,Op,Subs,[]), !, % associative & commutative operator detected
2964 maplist(strip_and_norm_ast_aux,Subs,NSubs), % Subs are already unwrapped
2965 sort(NSubs,Sorted), % in case there are associative operators that are not commutative: insert is_commutative check
2966 safe_univ_no_cutoff(Res,[Op|Sorted]).
2967 strip_and_norm_ast_aux(Expr,Res) :-
2968 assoc_subs(Expr,Op,Subs,[]), !, % associative operator detected
2969 maplist(strip_and_norm_ast_aux,Subs,NSubs), % Subs are already unwrapped
2970 safe_univ_no_cutoff(Res,[Op|NSubs]).
2971 strip_and_norm_ast_aux(Expr,SNExpr) :-
2972 syntaxtransformation(Expr,Subs,_,NSubs,SExpr),
2973 strip_and_norm_ast_l(Subs,NSubs),
2974 norm_strip(SExpr,SNExpr).
2975
2976 strip_and_norm_ast_l([],[]).
2977 strip_and_norm_ast_l([TExpr|Trest],[NExpr|Nrest]) :-
2978 strip_and_norm_ast(TExpr,NExpr),
2979 strip_and_norm_ast_l(Trest,Nrest).
2980
2981 norm_strip(greater_equal(A,B),less_equal(B,A)) :- !.
2982 norm_strip(greater(A,B),less(B,A)) :- !.
2983 norm_strip(set_extension(NL),set_extension(SNL)) :- !,
2984 sort(NL,SNL).
2985 norm_strip(Old,New) :-
2986 functor(Old,Functor,2),
2987 is_commutative(Functor),!,
2988 arg(1,Old,OA),
2989 arg(2,Old,OB),
2990 ( OA @> OB -> New =.. [Functor,OB,OA]
2991 ; New=Old).
2992 norm_strip(Old,Old).
2993 % TO DO: flatten associative operators into lists !
2994
2995 comm_assoc_subs(conjunct(TA,TB),conjunct) --> !,
2996 {get_texpr_expr(TA,A), get_texpr_expr(TB,B)},
2997 comm_assoc_subs(A,conjunct), comm_assoc_subs(B,conjunct).
2998 comm_assoc_subs(disjunct(TA,TB),disjunct) --> !,
2999 {get_texpr_expr(TA,A), get_texpr_expr(TB,B)},
3000 comm_assoc_subs(A,disjunct), comm_assoc_subs(B,disjunct).
3001 comm_assoc_subs(add(TA,TB),add) --> !,
3002 {get_texpr_expr(TA,A), get_texpr_expr(TB,B)},
3003 comm_assoc_subs(A,add), comm_assoc_subs(B,add).
3004 comm_assoc_subs(multiplication(TA,TB),multiplication) --> !,
3005 {get_texpr_expr(TA,A), get_texpr_expr(TB,B)},
3006 comm_assoc_subs(A,multiplication), comm_assoc_subs(B,multiplication).
3007 comm_assoc_subs(union(TA,TB),union) --> !,
3008 {get_texpr_expr(TA,A), get_texpr_expr(TB,B)},
3009 comm_assoc_subs(A,union), comm_assoc_subs(B,union).
3010 comm_assoc_subs(intersection(TA,TB),intersection) --> !,
3011 {get_texpr_expr(TA,A), get_texpr_expr(TB,B)},
3012 comm_assoc_subs(A,intersection), comm_assoc_subs(B,intersection).
3013 comm_assoc_subs(Expr,Op) --> {nonvar(Op)},[Expr]. % base case for other operators
3014
3015 % detect just associative operators
3016 assoc_subs(concat(TA,TB),concat) --> !,
3017 {get_texpr_expr(TA,A), get_texpr_expr(TB,B)},
3018 assoc_subs(A,concat), assoc_subs(B,concat).
3019 assoc_subs(composition(TA,TB),composition) --> !,
3020 {get_texpr_expr(TA,A), get_texpr_expr(TB,B)},
3021 assoc_subs(A,composition), assoc_subs(B,composition).
3022 assoc_subs(Expr,Op) --> {nonvar(Op)},[Expr]. % base case for other operators
3023
3024 is_commutative(conjunct).
3025 is_commutative(disjunct).
3026 is_commutative(equivalence).
3027 is_commutative(equal).
3028 is_commutative(not_equal).
3029 is_commutative(add).
3030 is_commutative(multiplication).
3031 is_commutative(union).
3032 is_commutative(intersection).
3033
3034 % check if two type expressions are same modulo info fields and reordering of commutative operators
3035 % same_texpr does not reorder wrt commutativity.
3036 same_norm_texpr(TExpr1,TExpr2) :-
3037 strip_and_norm_ast(TExpr1,N1),
3038 strip_and_norm_ast(TExpr2,N1).
3039
3040
3041 % small utility to get functor of texpr:
3042 get_texpr_functor(b(E,_,_),F,N) :- !, functor(E,F,N).
3043 get_texpr_functor(E,_,+) :- add_error_fail(get_texpr_functor,'Not a typed expression: ',E).
3044
3045 % -------------------------
3046
3047 % check if a ProB type is a set type:
3048 is_set_type(set(Type),Type).
3049 is_set_type(seq(Type),couple(integer,Type)).
3050 % should we have a rule for any ?? : in all cases using is_set_type any seems not possible; better that we generate error message in get_set_type or get_texpr_set_type
3051 % is_set_type(any,any).
3052
3053 get_set_type(TypeX,Res) :-
3054 ? (is_set_type(TypeX,SetType) -> Res=SetType ; add_error_fail(get_set_type,'Not a set type: ',TypeX)).
3055
3056 get_texpr_set_type(X,Res) :- get_texpr_type(X,TypeX),
3057 get_set_type(TypeX,Res).
3058
3059
3060 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
3061 % check if a set contains all elements of a type, i.e., maximal type
3062 is_just_type(Expr) :- is_just_type(Expr,[]).
3063 % is_just_type(+Expr,+RTT):
3064 % like is_just_type/1 but RTT is a list of identifiers (without type information)
3065 % of variables or constants that are known to be types, too.
3066 % E.g. is_just_type(a ** INTEGER) would fail but is_just_type(a ** INTEGER,[a]) would
3067 % succeed.
3068 is_just_type(b(E,T,I),RTT) :- is_just_type3(E,T,I,RTT).
3069
3070
3071 is_just_type3(identifier(G),set(Type),Infos,RefsToTypes) :-
3072 ( Type = global(G),
3073 memberchk(given_set,Infos) % no accidental local variable G that hides global G
3074 ; memberchk(G,RefsToTypes) -> true
3075 %; Type = freetype(G),
3076 % memberchk(given_set,Infos) % no accidental local variable G that hides global G
3077 % TODO: we do not know if the Freetype has restrictions (which are encoded in the PROPERTIES)
3078 ),!.
3079 is_just_type3(freetype_set(_),_,_,_).
3080 is_just_type3(pow_subset(E),_,_,RTT) :- is_just_type(E,RTT).
3081 is_just_type3(fin_subset(E),T,_,RTT) :-
3082 is_finite_type_in_context(proving,T), % animation or proving
3083 is_just_type(E,RTT).
3084 is_just_type3(integer_set('INTEGER'),set(integer),_,_).
3085 is_just_type3(bool_set,set(boolean),_,_).
3086 is_just_type3(real_set,set(real),_,_).
3087 is_just_type3(string_set,set(string),_,_).
3088 is_just_type3(cartesian_product(A,B),_,_,RTT) :-
3089 is_just_type(A,RTT),is_just_type(B,RTT).
3090 is_just_type3(mult_or_cart(A,B),_,_,RTT) :- % is_just_type/1 could be called before the cleanup
3091 is_just_type(A,RTT),is_just_type(B,RTT). % of an expression has finished
3092 is_just_type3(relations(A,B),_,_,RTT) :-
3093 is_just_type(A,RTT),is_just_type(B,RTT).
3094 is_just_type3(struct(b(rec(Fields),_,_)),_,_,RTT) :-
3095 maplist(field_is_just_type(RTT),Fields).
3096 is_just_type3(typeset,_,_,_).
3097 is_just_type3(comprehension_set(_,b(truth,_,_)),_,_,_).
3098 is_just_type3(value(Val),ST,_,_) :- is_set_type(ST,Type), is_maximal_value(Val,Type). % also see: quick_is_definitely_maximal_set(Val).
3099
3100 field_is_just_type(RTT,field(_,Set)) :- is_just_type(Set,RTT).
3101
3102 is_maximal_value(V,_) :- var(V),!,fail.
3103 is_maximal_value(global_set(GS),Type) :- (GS=='INTEGER' -> true ; Type==global(GS)). % we could call is_maximal_global_set(GS) or b_global_set (but requires compiled)
3104
3105 % Generate a custom matching / visitor predicate
3106 % bsyntaxtree:gen_visitor(bexpr_variables_aux,bexpr_variables)
3107 /*
3108 gen_visitor(Pred, BodyPred) :- syntaxelement(Expr,SubsX,_NamesX,_Lists,_ConstantX,_),
3109 print_clause(Pred,BodyPred,Expr,SubsX),
3110 fail.
3111 gen_visitor(Pred, BodyPred) :- nl.
3112
3113 print_clause(Pred,BodyPred,Expr,SubsX) :- E=..[Op|SubsX], format('~w(~w) :- ',[Pred,Expr]).
3114 */
3115
3116 /*
3117 * create_recursive_compset(+Ids,+Cond,+Type,+Infos,-RecId,-TCompSet)
3118 * creates a recursive comprehension set:
3119 * Ids is the list of the introduced typed identifiers
3120 * Cond is the condition (a typed predicate)
3121 * Infos are additional informations for the comprehension set syntax element
3122 * RecId is the identifier (untyped, an atom) that can be used in Cond to refer to the
3123 * comprehension set recursively. Usually RecId is used in Cond as a variable
3124 * TCompSet is the generated recursive comprehension set, the recursion parameter is introduced
3125 * by a recusive(Id,CompSet) syntax element
3126 */
3127 create_recursive_compset(Ids,Cond,Type,Infos,RecId,TCompSet) :-
3128 unique_id("recursive.",RecId),
3129 add_symbolic_annotation(Infos,RInfos),
3130 create_texpr(comprehension_set(Ids,Cond),Type,RInfos,TCompSet1),
3131 create_typed_id(RecId,Type,TRecId),
3132 create_texpr(recursive_let(TRecId,TCompSet1),Type,[],TCompSet).
3133
3134 unique_typed_id(Prefix,Type,TId) :-
3135 unique_id(Prefix,Id),
3136 create_typed_id(Id,Type,TId).
3137
3138
3139 mark_bexpr_as_symbolic(b(E,T,I),b(E2,T,RI)) :-
3140 add_symbolic_annotation(I,RI),
3141 mark_aux(E,E2).
3142 mark_aux(union(A,B),R) :- !, R=union(SA,SB),
3143 mark_bexpr_as_symbolic(A,SA), mark_bexpr_as_symbolic(B,SB).
3144 % union is currently the only operator that is kept symbolically
3145 mark_aux(A,A).
3146
3147 add_symbolic_annotation([H|I],R) :- H == prob_annotation('SYMBOLIC'),!, R=[H|I].
3148 add_symbolic_annotation(I,R) :- !, R=[prob_annotation('SYMBOLIC')|I].
3149
3150 % identifier_sub_ast(+TExpr,+Identifier,-SubPosition):
3151 % Find occurences of an identifier "Identifier" in an expression "TExpr"
3152 % Returns a list of positions (beginning with 0) that describes the position of a sub-expression
3153 % that contains all occurrences of Identifier in TExpr.
3154 % E.g. [1,0,1] means "second sub-expression of TExpr, then the first sub-expression of that,
3155 % then the second sub-expression of that".
3156 % When an identifier has multiple occurences, the position of the sub-expression is returned
3157 % where all occurences of it are located.
3158 % If the identifier is not found, the call fails.
3159 % Sub-expressions are meant like the ones syntaxtraversion or syntaxtransformation return.
3160 identifier_sub_ast(TExpr,Identifier,SubPosition) :-
3161 syntaxtraversion(TExpr,Expr,_Type,_Infos,AllSubs,Names),
3162 identifier_sub_ast_aux(Expr,AllSubs,Names,Identifier,SubPosition).
3163 identifier_sub_ast_aux(identifier(Identifier),[],[],Identifier,[]) :- !.
3164 identifier_sub_ast_aux(_Expr,AllSubs,Names,Identifier,SubPosition) :-
3165 get_texpr_id(TId,Identifier),nonmember(TId,Names),
3166 % For each sub-expression E in the list AllSubs create a term Pos-E
3167 % where Pos is E's position (starting with 0) in AllSubs
3168 foldl(annotate_pos,AllSubs,AllAnnotatedSubs,0,_),
3169 % Introduced identifiers occur alsa as sub-expressions, remove those
3170 foldl(select_sub,Names,AllAnnotatedSubs,RealAnnSubs),
3171 convlist_max(identifier_sub_ast_aux2(Identifier),2,RealAnnSubs,SubPositions), % find at most 2 sols
3172 ( SubPositions = [SubPosition] -> true
3173 ; SubPositions = [_,_|_] -> % More then one occurrences - make this the found node
3174 SubPosition = []).
3175 identifier_sub_ast_aux2(Identifier,Pos-TExpr,[Pos|SubPosition]) :-
3176 identifier_sub_ast(TExpr,Identifier,SubPosition).
3177 annotate_pos(TExpr,I-TExpr,I,I2) :- I2 is I+1.
3178 select_sub(Name,AnnotatedSubs,Result) :-
3179 selectchk(_Pos-Name,AnnotatedSubs,Result).
3180
3181
3182
3183 % exchange_ast_position(+SubPosition,+OldTExpr,-OldInner,+NewInner,-NewTExpr):
3184 % exchanges a sub-expression in the expression "OldTExpr".
3185 % SubPosition is a list of positions like identifier_sub_ast/3 returns it.
3186 % OldInner is the sub-expression found in OldTExpr.
3187 % NewInner is the new sub-expression.
3188 % NewTExpr is the new expression that originates from replacing OldInner by NewInner.
3189 exchange_ast_position([],Old,Old,New,New).
3190 exchange_ast_position([Pos|RestPos],OldTExpr,OldInner,NewInner,NewTExpr) :-
3191 remove_bt_and_used_ids(OldTExpr,OldExpr,NewExpr,NewTExpr), % also invalidates used_ids info
3192 syntaxtransformation(OldExpr,Subs,_Names,NSubs,NewExpr),
3193 nth0(Pos,Subs, OldSelected,Rest),
3194 nth0(Pos,NSubs,NewSelected,Rest),
3195 exchange_ast_position(RestPos,OldSelected,OldInner,NewInner,NewSelected).
3196
3197
3198 % -----------------------
3199 % utility to expand / inline all let expressions and let predicates:
3200 % useful for tools that cannot handle the lets
3201
3202 expand_all_lets(Expr,NewExpr) :-
3203 transform_bexpr(tl_expand_lets,Expr,NewExpr).
3204
3205 tl_expand_lets(b(E,_,_),Res) :- tl_expand_lets2(E,Res).
3206 tl_expand_lets2(let_expression(Ids,Exprs,Body),NewBody) :- % expand LET expression
3207 replace_ids_by_exprs(Body,Ids,Exprs,NewBody).
3208 tl_expand_lets2(let_predicate(Ids,Exprs,Body),NewBody) :- % expand LET predicate
3209 replace_ids_by_exprs(Body,Ids,Exprs,NewBody).
3210
3211 % -----------------------
3212
3213 :- public check_used_ids/2.
3214 % a simple checker, only checks used_ids info fields for entire typed expression:
3215 check_used_ids(TExpr,PP) :- %format('CHECK AST for ~w~n',[PP]),
3216 map_over_typed_bexpr(check_used_ids_texpr_fail(PP),TExpr).
3217 check_used_ids(_,_).
3218 check_used_ids_texpr_fail(PP,E) :- check_used_ids_texpr(PP,E),!,fail.
3219 check_used_ids_texpr(PP,b(P,T,I)) :- member(used_ids(UIds1),I),!,
3220 (find_identifier_uses(b(P,T,I),[],UIds2) -> true
3221 ; add_internal_error('find_identifier_uses failed',PP),fail),
3222 (UIds1==UIds2 -> true
3223 ; format('*** Wrong used_ids Info (~w)!!~n Used_ids: ~w~n Comp_ids: ~w~n',[PP,UIds1,UIds2]),
3224 translate:print_bexpr(b(P,T,I)),nl,
3225 add_error(check_used_ids,'Wrong used_ids: ',PP,I)
3226 ).
3227 check_used_ids_texpr(_,_).
3228
3229 % repair any broken used_ids info in typed expression TExpr and re-compute used_ids if necessary
3230 % PP is a program point, will be reported in case of an error
3231 repair_used_ids(PP,TExpr,Res) :-
3232 (transform_bexpr(bsyntaxtree:repair_used_ids_info(PP),TExpr,NewTExpr) -> Res=NewTExpr
3233 ; add_internal_error('Repairing used_ids failed:',PP),
3234 Res=TExpr).
3235
3236 % we could also simply call recompute_used_ids_inf; but it would not generate any messages
3237 repair_used_ids_info(PP,b(P,T,I),b(P,T,NI)) :- %functor(P,FF,_), print(repair(FF)),nl,
3238 select(used_ids(OldUsed),I,I2),!,
3239 (find_identifier_uses(b(P,T,I),[],NewUsed)
3240 -> (NewUsed=OldUsed -> NI=I
3241 ; NI = [used_ids(NewUsed)|I2],
3242 add_message(repair_used_ids,'Updating used_ids for: ',b(P,T,I),I2)
3243 )
3244 ; add_internal_error('find_identifier_uses failed',PP),
3245 NI=I
3246 ).
3247 repair_used_ids_info(PP,b(P,T,I),b(P,T,NI)) :-
3248 requires_used_ids(P),
3249 (find_identifier_uses(b(P,T,I),[],NewUsed) -> true
3250 ; add_internal_error('find_identifier_uses failed',PP),fail
3251 ),
3252 !,
3253 NI=[used_ids(NewUsed)|I].
3254 repair_used_ids_info(_,B,B).
3255
3256 requires_used_ids(exists(_,_)).
3257 requires_used_ids(forall(_,_,_)).
3258
3259 % a simple checker to see if an AST is well-formed:
3260 % can be tested e.g. as follows: b_get_invariant_from_machine(I), check_ast(I).
3261 % called in prob_safe_mode by clean_up_section
3262
3263 check_ast(TE) :- check_ast(false,TE).
3264 check_ast(AllowVars,TExpr) :- %nl,print('CHECK AST'),nl,
3265 map_over_typed_bexpr(check_ast_texpr(AllowVars),TExpr).
3266 check_ast(_,_).
3267
3268 :- use_module(typing_tools,[valid_ground_type/1]).
3269 %check_ast_texpr(X) :- print(check(X)),nl,fail.
3270 check_ast_texpr(AllowVars,AST) :- AST = b(E,Type,Infos),
3271 (debug:debug_level_active_for(9) -> write(' check_ast: '),print_bexpr(AST), write(' :: '), write(Type), nl ; true),
3272 (check_expr(E,Type,Infos) -> true
3273 ; add_error(check_ast_texpr,'Invalid Expr: ', AST) %, trace, check_expr(E,Type,Infos)
3274 ),
3275 (check_type(Type,AllowVars) -> true
3276 ; add_error(check_ast_texpr,'Invalid Type for: ',AST,Infos)),
3277 safe_functor(E,F),
3278 check_ast_typing(E,Type,Infos),
3279 (check_infos(Infos,F) -> true ; add_error(check_ast_texpr,'Invalid Infos: ',AST)),
3280 check_special_rules(E,Type,Infos),
3281 fail. % to force backtracking in map_over_typed_bexpr
3282
3283
3284 check_special_rules(operation_call_in_expr(Operation,_),_,OInfos) :- !,
3285 get_texpr_info(Operation,Info), % reads info important for used_ids computation
3286 (memberchk(reads(_V),Info) -> true
3287 ; add_error(check_ast_texpr,'Missing reads info: ',Operation,OInfos)).
3288
3289
3290 safe_functor(V,R) :- var(V),!,R='$VAR'.
3291 safe_functor(E,F/N) :- functor(E,F,N).
3292
3293 % check whether the type term is ok
3294 check_type(X,AllowVars) :- var(X),!,
3295 (AllowVars==true -> true ; add_error(check_type,'Variable type: ',X),fail).
3296 check_type(pred,_) :- !.
3297 check_type(subst,_) :- !.
3298 check_type(op(Paras,Returns),AllowVars) :- !,
3299 maplist(check_normal_type(AllowVars),Paras),
3300 maplist(check_normal_type(AllowVars),Returns).
3301 check_type(T,AllowVars) :- check_normal_type(AllowVars,T).
3302
3303 check_normal_type(AllowVars,T) :-
3304 (AllowVars \== true -> valid_ground_type(T)
3305 ; ground(T) -> valid_ground_type(T)
3306 ; true). % TO DO: call valid_ground_type but pass AllowVars
3307
3308 :- use_module(probsrc(btypechecker), [lookup_type_for_expr/2, unify_types_werrors/4]).
3309 % check whether type is compatible with operators
3310 check_ast_typing(member(A,B),Type,Pos) :- !,
3311 get_texpr_type(B,TB), check_set_type(TB,member,Pos),
3312 check_type(Type,pred,member),
3313 get_texpr_type(A,TA),
3314 unify_types_werrors(set(TA),TB,Pos,member).
3315 check_ast_typing(not_equal(A,B),Type,Pos) :- !, check_ast_typing(equal(A,B),Type,Pos).
3316 check_ast_typing(equal(A,B),Type,Pos) :- !,
3317 get_texpr_type(B,TB),
3318 get_texpr_type(A,TA),
3319 unify_types_werrors(TA,TB,Pos,'='),
3320 (non_value_type(TA)
3321 -> add_error(check_ast_typing,'Binary predicate has to have values as arguments:',TA,Pos)
3322 ; Type=pred -> true
3323 ; add_error(check_ast_typing,'Illegal type for binary predicate:',Type,Pos)
3324 ).
3325 check_ast_typing(greater_equal(A,B),Type,_) :- !,
3326 get_texpr_type(A,TA),check_type(TA,integer,greater_equal),
3327 get_texpr_type(B,TB),check_type(TB,integer,greater_equal), check_type(Type,pred,member).
3328 check_ast_typing(Expr,Type,Pos) :-
3329 syntaxtransformation(Expr,Subs,Names,NSubs,NewExpr),
3330 check_names(Names,Pos),
3331 (lookup_type(NewExpr,T) -> true
3332 ; add_warning(check_ast_typing,'Unable to lookup type for: ',NewExpr),
3333 fail
3334 ),
3335 !,
3336 (unify_types_werrors(Type,T,Pos,'check_ast')
3337 -> maplist(check_sub_type(Expr,Pos),Subs,NSubs)
3338 ; add_error(check_ast_typing,'Type mismatch for expression:',Expr,Pos)
3339 ).
3340 check_ast_typing(_,subst,_) :- !. % ignore subst for the moment
3341 check_ast_typing(operation(_TName,_Res,_Params,_TBody),_,_) :- !. % ignore operations for the moment
3342 check_ast_typing(Expr,_,Pos) :-
3343 syntaxtransformation(Expr,_,_Names,_,_NewExpr),!,
3344 add_message(check_ast_typing,'Cannot lookup type for expression: ',Expr,Pos).
3345 check_ast_typing(Expr,_,Pos) :-
3346 add_message(check_ast_typing,'No applicable type rule for expression: ',Expr,Pos).
3347
3348 non_value_type(X) :- var(X),!,fail.
3349 non_value_type(pred).
3350 non_value_type(subst).
3351 non_value_type(op(_)).
3352
3353
3354 check_names([],_).
3355 check_names([H|T],Pos) :-
3356 (member(H,T) -> add_error(check_ast_name,'Duplicate name:',H,Pos) ; check_names(T,Pos)).
3357
3358 check_sub_type(OuterExpr,Pos,Arg,Type) :- get_texpr_type(Arg,T),!,
3359 (unify_types_werrors(Type,T,Pos,'check_sub_type') -> true
3360 ; add_error(check_ast_typing,'Type mismatch for sub-expression:',Arg,Pos),
3361 write('Outer expression: '),translate:print_bexpr(OuterExpr),nl,
3362 write('Outer type: '),write(Type),nl,
3363 write('Arg type: '),write(T),nl,print(type(T)),nl, tools_printing:print_term_summary(Arg),nl,trace
3364 ).
3365 check_sub_type(_,Pos,Arg,_) :-
3366 add_error(check_ast_typing,'Cannot extract type: ',Arg,Pos).
3367
3368 lookup_type(identifier(_),_) :- !. % ignore typing issues for identifiers
3369 lookup_type(Expr,Type) :- lookup_type_for_expr(Expr,Type).
3370
3371 check_set_type(Var,_,_) :- var(Var),!.
3372 check_set_type(set(_),_,_) :- !.
3373 check_set_type(seq(_),_,_) :- !.
3374 check_set_type(Type,Func,Pos) :- add_error(check_ast_typing,'Invalid type for operator: ',Func:Type,Pos).
3375
3376 check_type(Type,Type,_) :- !.
3377 check_type(Type,_,Func) :- add_error(check_ast_typing,'Unexpected type for operator: ',Func:Type).
3378
3379 check_infos(X,F) :- var(X),!, add_error(check_infos,'Info field list not terminated: ',F:X),fail.
3380 check_infos([],_).
3381 check_infos([H|_],F) :- \+ ground(H),!, add_error(check_infos,'Info field not ground: ',F:H),fail.
3382 check_infos([[H|T]|_],F) :- !, add_error(check_infos,'Info field contains nested list: ',F:[H|T]),fail.
3383 check_infos([cse_used_ids(H)|T],F) :- member(cse_used_ids(H2),T),!,
3384 add_error(check_infos,'Multiple cse_used_ids entries: ',F:[H,H2]),fail.
3385 check_infos([used_ids(H)|T],F) :- member(used_ids(H2),T),!,
3386 add_error(check_infos,'Multiple used_ids entries: ',F:[H,H2]),fail.
3387 check_infos([nodeid(N1)|T],F) :- member(nodeid(N2),T),!,
3388 add_error(check_infos,'Multiple nodeid entries: ',F:[N1,N2],[nodeid(N1)]),fail.
3389 check_infos([removed_typing|T],F) :- member(removed_typing,T),!,
3390 add_error(check_infos,'Multiple removed_typing entries: ',F,T),fail.
3391 check_infos([_|T],F) :- check_infos(T,F).
3392
3393 check_expr(Expr,Type,Infos) :- nonmember(contains_wd_condition,Infos),
3394 sub_expression_contains_wd_condition(Expr,Sub),
3395 TE = b(Expr,Type,Infos),
3396 (Type = subst
3397 -> fail % AST cleanup is not called for substitutions; WD-info not available for substitutions at the moment
3398 ; translate_bexpression(TE,PS)),
3399 functor(Expr,Functor,_),
3400 functor(Sub,SubFunctor,_),
3401 tools:ajoin(['Node for AST node ',Functor,' does not contain WD info from Subexpression ',SubFunctor,' :'],Msg),
3402 add_warning(check_expr,Msg,PS,TE).
3403 % well_def_analyser:nested_print_wd_bexpr(TE),nl.
3404 % TODO: check when we have an unnecessary WD condition
3405 check_expr(Expr,Type,Infos) :- nonmember(contains_wd_condition,Infos),
3406 always_not_wd_top(Expr),
3407 add_warning(check_expr,'AST is not well-defined but does not contain WD info: ',b(Expr,Type,Infos),Infos).
3408 check_expr(member(LHS,RHS),Type,Infos) :- is_just_type(RHS),
3409 get_preference(optimize_ast,true),
3410 !,
3411 TE = b(member(LHS,RHS),Type,Infos),
3412 translate:translate_bexpression(TE,PS),
3413 add_warning(check_expr,'AST contains redundant typing predicate: ',PS,TE).
3414 check_expr(identifier(ID),_,_) :- illegal_id(ID),!,
3415 add_error(check_infos,'Illegal identifier: ', identifier(ID)).
3416 check_expr(lazy_lookup_expr(ID),_,_) :- illegal_id(ID),!,
3417 add_error(check_infos,'Illegal identifier: ', lazy_lookup_expr(ID)).
3418 check_expr(lazy_lookup_pred(ID),_,_) :- illegal_id(ID),!,
3419 add_error(check_infos,'Illegal identifier: ', lazy_lookup_pred(ID)).
3420 check_expr(exists(Parameters,Condition),pred,Infos) :- !,
3421 check_used_ids(exists,Parameters,Condition,Infos,_Used).
3422 check_expr(forall(Parameters,LHS,RHS),pred,Infos) :- !,
3423 create_implication(LHS,RHS,Condition),
3424 check_used_ids(forall,Parameters,Condition,Infos,_Used). %
3425 check_expr(value(V),Type,_) :- !, check_bvalue(V,Type).
3426 check_expr(_,_,_).
3427
3428 % will check all used_ids fields (not just for exists and forall)
3429 :- public check_used_ids_in_ast/1.
3430 check_used_ids_in_ast(closure(_,_,TExpr)) :- !, (map_over_typed_bexpr(check_used_ids_aux,TExpr) ; true).
3431 check_used_ids_in_ast(TExpr) :- map_over_typed_bexpr(check_used_ids_aux,TExpr).
3432 check_used_ids_in_ast(_).
3433
3434 check_used_ids_aux(AST) :- AST = b(_,_,Infos),
3435 member(used_ids(_),Infos),!,
3436 find_identifier_uses_if_necessary(AST,[],_), % will perform check
3437 fail.
3438
3439 % --------------------
3440
3441 :- use_module(specfile,[eventb_mode/0, z_or_tla_minor_mode/0]).
3442 % check if an expression is definitely not WD; looking at the top-level operator only
3443 always_not_wd_top(function(X,_)) :- definitely_empty_set(X). % TODO: detect a few more cases, e.g., arg not in dom
3444 always_not_wd_top(power_of(X,Y)) :- (get_integer(Y,VY), VY < 0 -> true
3445 ; eventb_mode, get_integer(X,VX), VX < 0).
3446 always_not_wd_top(div(_,Val)) :- get_integer(Val,VV), VV==0.
3447 always_not_wd_top(modulo(X,Y)) :-
3448 (get_integer(Y,VY), VY=<0
3449 -> true % there seems to be a def for Z in Z Live, cf modulo2
3450 ; get_integer(X,VX), VX<0, \+ z_or_tla_minor_mode).
3451 always_not_wd_top(min(X)) :- definitely_empty_set(X).
3452 always_not_wd_top(max(X)) :- definitely_empty_set(X).
3453 always_not_wd_top(size(X)) :- definitely_not_sequence(X). % TODO: detect infinite sets; also for card(_)
3454 always_not_wd_top(first(X)) :- definitely_not_non_empty_sequence(X).
3455 always_not_wd_top(front(X)) :- definitely_not_non_empty_sequence(X).
3456 always_not_wd_top(last(X)) :- definitely_not_non_empty_sequence(X).
3457 always_not_wd_top(tail(X)) :- definitely_not_non_empty_sequence(X).
3458 always_not_wd_top(general_intersection(X)) :- definitely_empty_set(X).
3459
3460 definitely_not_non_empty_sequence(X) :-
3461 (definitely_empty_set(X) -> true ; definitely_not_sequence(X)).
3462
3463 :- use_module(avl_tools,[avl_min_pair/3]).
3464 definitely_not_sequence(b(value(A),_,_)) :- nonvar(A), A=avl_set(AVL),
3465 avl_min_pair(AVL,int(StartIndex),_), StartIndex \= 1.
3466 % TODO: treat set_extension
3467
3468 :- use_module(b_ast_cleanup,[check_used_ids_info/4]).
3469 check_used_ids(Quantifier,Parameters,Condition,Infos,Used) :-
3470 select(used_ids(Used),Infos,Rest)
3471 -> check_used_ids_info(Parameters,Condition,Used,Quantifier), %% comment in to check used_ids field
3472 (member(used_ids(_),Rest)
3473 -> add_internal_error('Multiple used_ids info fields:',Parameters:Infos) ; true)
3474 ;
3475 add_internal_error(
3476 'Expected information of used identifiers information',Quantifier:Parameters:Infos).
3477
3478 illegal_id(ID) :- var(ID),!.
3479 illegal_id(op(ID)) :- !, \+ atom(ID).
3480 illegal_id(ID) :- \+ atom(ID).
3481
3482 :- use_module(btypechecker, [unify_types_strict/2, couplise_list/2]).
3483 :- use_module(avl_tools,[check_is_non_empty_avl/1]).
3484 % TO DO: we could check type more
3485 check_bvalue(V,_) :- var(V),!.
3486 check_bvalue(avl_set(A),Type) :- !, unify_types_strict(Type,set(_)),
3487 check_is_non_empty_avl(A).
3488 check_bvalue(closure(_,T,B),Type) :- !,
3489 couplise_list(T,CT), unify_types_strict(set(CT),Type),
3490 check_ast(B).
3491 check_bvalue(_,_).
3492
3493 % -----------------------
3494
3495
3496 indent_ws(X) :- X<1,!.
3497 indent_ws(X) :- print(' '), X1 is X-1, indent_ws(X1).
3498
3499 print_ast_td(b(E,T,I),Level,L1) :-
3500 indent_ws(Level),
3501 (E=identifier(_)
3502 -> format('~w (~w) -> ~w~n',[E,T,I])
3503 ; functor(E,F,N),
3504 format('~w/~w (~w) -> ~w~n',[F,N,T,I])
3505 ),
3506 L1 is Level+1.
3507 print_ast(TExpr) :-
3508 (map_over_typed_bexpr_top_down_acc(print_ast_td,TExpr,0),fail ; true).
3509
3510 % ---------------------
3511
3512 :- dynamic count_id_usage/2.
3513 single_usage_id_count(Expr) :- uses_an_identifier(Expr,Id),
3514 retract(count_id_usage(Id,Count)),
3515 !,
3516 Count=0,
3517 C1 is Count+1,
3518 assertz(count_id_usage(Id,C1)).
3519 single_usage_id_count(_).
3520
3521 % check if an identifier is used at most once
3522 single_usage_identifier(ID,ExprOrPredicates,Count) :-
3523 retractall(count_id_usage(_,_)),
3524 assertz(count_id_usage(ID,0)),
3525 % TO DO: take care of naming; do not count occurences when we enter scope defining ID
3526 maplist(single_usage_cnt,ExprOrPredicates),
3527 retract(count_id_usage(ID,Count)).
3528
3529 single_usage_cnt(ExprOrPredicate) :- map_over_full_bexpr_no_fail(single_usage_id_count,ExprOrPredicate).
3530
3531 gen_fresh_id_if_necessary(Default,Expr,FreshID) :-
3532 occurs_in_expr(Default,Expr),!,
3533 gensym('__FRESH_ID__',FreshID). % assumes _Fresh_XXX not used
3534 gen_fresh_id_if_necessary(Default,_,Default).
3535
3536 %% rewrite_if_then_else_expr_to_b(IfThenElseExpr, NExpr).
3537 % Rewrite if-then-else expr to B as understood by Atelier-B.
3538 % {d,x| d:BOOL & If => x=Then & not(if) => x=Else}(TRUE)
3539 rewrite_if_then_else_expr_to_b(if_then_else(If,Then,Else), NExpr) :-
3540 get_texpr_type(Then,Type),
3541 ARG = b(boolean_true,boolean,[]), AT=boolean, % we could use unit type or BOOL here
3542 gen_fresh_id_if_necessary('_zzzz_unary',b(if_then_else(If,Then,Else),Type,[]),AID1),
3543 gen_fresh_id_if_necessary('_zzzz_binary',b(if_then_else(If,Then,Else),Type,[]),AID2),
3544 safe_create_texpr(identifier(AID1), AT, [], Id1), % a dummy argument
3545 safe_create_texpr(identifier(AID2), Type, [], Id2), % The result
3546 safe_create_texpr(equal(Id2,Then), pred, [], Eq1),
3547 safe_create_texpr(equal(Id2,Else), pred, [], Eq2),
3548 safe_create_texpr(implication(If,Eq1), pred, [], Pred1),
3549 safe_create_texpr(negation(If), pred, [], NIf),
3550 safe_create_texpr(implication(NIf,Eq2), pred, [], Pred2),
3551 safe_create_texpr(conjunct(Pred1,Pred2), pred, [], Pred),
3552 safe_create_texpr(comprehension_set([Id1,Id2],Pred), set(couple(AT,Type)), [], FUN),
3553 NExpr = function(FUN,ARG).