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
6		:- module(b_interpreter,
7		[b_test_boolean_expression/4, b_test_boolean_expression/6,
8		%b_test_boolean_expression_wf/3,
9		b_test_boolean_expression_cs/5,
10		b_test_boolean_expression_for_ground_state/4, b_test_boolean_expression_for_ground_state/5,
11		% b_det_test_boolean_expression/6,
12		b_not_test_boolean_expression/4, b_not_test_boolean_expression/6,
13		%b_not_test_boolean_expression_wf/3,
14		b_not_test_boolean_expression_cs/5,
15
16		b_convert_bool/5,
17		b_convert_bool_timeout/7,
18		b_compute_expression/5,
19
20		b_execute_top_level_statement/7,
21		b_execute_statement_nowf/5,
22
23		b_compute_expression_nowf/4, b_compute_expression_nowf/6, b_compute_expression_nowf/7,
24		b_compute_explicit_epression_no_wf/6, b_compute_explicit_epression_no_wf/7,
25
26		b_set_up_concrete_constants/2, b_partial_set_up_concrete_constants/1,
27		b_initialise_machine/4,
28
29		b_execute_top_level_operation_update/5, b_execute_top_level_operation_wf/8,
30
31		convert_list_of_expressions_into_set_wf/4,
32		%state_satisfies_negation_of_invariant/1,
33
34		b_state_violates_invariant/2,
35		state_violates_assertions/2,
36		analyse_invariant_for_state/1,
37
38		insert_before_substitution_variables/5, % add $0 values to a store
39
40		try_lookup_value_in_store_and_global_sets/3, lookup_value_in_store_and_global_sets_wf/7,
41		set_up_typed_localstate/6, set_up_typed_localstate2/8,
42		%set_up_localstate_for_let/7,
43
44		set_projection_on_static_assertions/1,
45
46		tcltk_unsatisfiable_components_exist/0,
47		tcltk_quick_describe_unsat_properties/2,
48
49		get_unsat_component_predicate/3,
50		properties_were_filtered/1, % true if PROPERTIES / axioms filtered due to prob-ignore pragmas
51		b_generate_for_all_list_domain_nolwf/8 % for predicate_evaluator
52		]).
53
54		:- meta_predicate not_with_enum_warning_and_possible_delay(0,-,?,?,?).
55		:- meta_predicate not_with_enum_warning_delay(0,-,?,?,?,?).
56
57		%:- use_module('../extensions/profiler/profiler.pl').
58		%:- use_module('../extensions/profiler/profiler_te.pl').
59		%:- enable_profiling(b_test_boolean_expression/4).
60		%:- enable_profiling(b_test_boolean_expression_cs/5).
61
62		:- use_module(kernel_objects).
63		:- use_module(bsets_clp).
64		:- use_module(delay).
65
66
67		:- use_module(kernel_mappings).
68		:- use_module(b_global_sets).
69		:- use_module(store).
70		:- use_module(library(lists)).
71		:- use_module(library(ordsets)).
72		:- use_module(library(avl)).
73
74		:- use_module(b_global_sets).
75		:- use_module(bmachine).
76		:- use_module(b_enumerate, [b_enumerate_values_in_store/5,
77		b_tighter_enumerate_all_values/2, b_tighter_enumerate_values_in_ctxt/3]).
78		:- use_module(debug).
79		:- use_module(performance_messages).
80		:- use_module(self_check).
81		:- use_module(tools).
82
83		:- use_module(module_information,[module_info/2]).
84		:- module_info(group,interpreter).
85		:- module_info(description,'This module provides the basic interpreter for expressions, predicates and substitutions.').
86
87		:- use_module(preferences).
88		:- use_module(error_manager).
89		:- use_module(typechecker).
90		:- use_module(specfile,[state_corresponds_to_initialised_b_machine/2
91		,state_corresponds_to_set_up_constants_only/2]).
92
93		:- use_module(bsyntaxtree).
94
95		:- use_module(translate).
96
97		:- use_module(kernel_waitflags).
98		:- use_module(kernel_reals).
99		:- use_module(kernel_records).
100
101		:- use_module(kodkodsrc(kodkod),[kodkod_request/5]).
102
103		:- use_module(custom_explicit_sets).
104		:- use_module(closures,[is_symbolic_closure/1,
105		mark_closure_as_symbolic/2, mark_closure_as_recursive/2, mark_closure/3]).
106
107		:- use_module(state_space).
108		:- use_module(b_interpreter_eventb).
109		:- use_module(tools_printing,[print_term_summary/1,print_functor/1]).
110		:- use_module(value_persistance,[load_partial_constants/3,lookup_cached_transitions/4]).
111		:- use_module(extrasrc(b_expression_sharing),[is_lazy_let_identifier/1]).
112		:- use_module(bool_pred,[negate/2]).
113		:- use_module(smt_solvers_interface(smt_solvers_interface),[smt_add_predicate/5]).
114
115		:- use_module(debug).
116		:- use_module(external_functions).
117
118		:- use_module(static_ordering,[sort_ids_by_usage/4,reorder_state/3]).
119		%:- use_module(bsyntaxtree,[predicate_has_ignore_pragma/1]).
120		:- use_module(tools_lists,[exclude_count/4, optimized_nth1/3]).
121		:- use_module(tools_meta, [safe_time_out/3]).
122
123		:- set_prolog_flag(double_quotes, codes).
124
125		/* ----------------------------------*/
126
127		/* For partial evaluation */
128
129		%:- use_module('~/cvs_root/cogen2/logen_source/runtime/logen_dispatcher.pl').
130
131		% new profiler
132		%:- use_module('../extensions/profiler/profiler.pl').
133		%:- use_module('../extensions/profiler/profiler_te.pl').
134		%:- enable_profiling_naming(b_interpreter:b_state_violates_invariant_aux/2,name).
135
136		%name(b_interpreter:b_state_violates_invariant_aux,_,INVERIANT).
137
138		%b_state_violates_invariant(ID,State) :-
139		% b_intepreter:b_state_violates_invariant_aux(ID,State).
140
141		% old profiler
142		:- use_module(runtime_profiler,[profile_single_call/3]).
143
144		% called by force_check_invariantKO and indirectly by model_checker (State was prepare_state_for_specfile_trans )
145		b_state_violates_invariant(ID,State) :-
146		b_state_violates_invariant_aux(ID,State).
147
148		b_state_violates_invariant_aux(ID,CurBState) :-
149		retract(specialized_inv(ID,AVL)), % Note: when we assert this we check that invariant holds in predecessor state
150		intersect_invs(AVL,SPO), !,
151		(SPO = b(truth,_,_) -> fail
152		; profile_single_call('INVARIANT-Specialized',ID,b_interpreter:b_state_violates_spec_invariant(ID,SPO,CurBState))).
153		b_state_violates_invariant_aux(ID,CurBState) :-
154		profile_single_call('INVARIANT',ID,b_interpreter:state_violates_invariant(ID,CurBState)).
155
156		b_state_violates_spec_invariant(ID,SPO,CurBState) :-
157		\+ check_invariant_predicate_with_time_out(ID,SPO,CurBState).
158
159		intersect_invs(invariant_preserved,Inv) :- !, Inv= b(truth,pred,[]).
160		intersect_invs([],Inv) :- !, add_internal_error('Illegal empty specialized inv list:', intersect_invs([],Inv)),
161		Inv = b(falsity,pred,[]).
162		intersect_invs(A,InvList) :-
163		avl_domain(A,OpList),
164		get_mask(OpList,Mask), %print(check(OpList,Mask)),nl,
165		findall(nth1_invariant(Nr), member(Nr,Mask), InvList).
166
167		% intersect all masks of specialized invariant nrs to be checked
168		get_mask([],[]).
169		get_mask([H|T],Res) :-
170		b_specialized_invariant_mask_for_op(H,Mask),get_mask3(T,Mask,Res).
171		get_mask3([],Acc,Acc).
172		get_mask3([H|T],Acc,Res) :-
173		b_specialized_invariant_mask_for_op(H,Mask),
174		ord_intersection(Mask,Acc,A1),
175		get_mask3(T,A1,Res).
176		/* ----------------------------------*/
177
178		:- load_files(library(system), [when(compile_time), imports([environ/2])]).
179
180
181		state_satisfies_invariant_aux(ID,State) :-
182		check_invariant_with_time_out(ID,State). % version without partial evaluation
183
184
185		:- use_module(library(timeout)).
186
187		:- use_module(tools_printing,[format_with_colour_nl/4]).
188		:- use_module(probsrc(specfile),[prepare_state_for_specfile_trans/3]).
189		% called by prob_cli when invariant violation found:
190		% we no longer have access to the specialized_inv facts
191		analyse_invariant_for_state(ID) :-
192		b_invariant_number_list(InvList),
193		visited_expression(ID,State),
194		prepare_state_for_specfile_trans(State,ID,PreparedCurState),
195		maplist(check_invariant(ID,PreparedCurState),InvList).
196		check_invariant(ID,State,InvariantNr) :-
197		enter_new_error_scope(L,check_invariant),
198		check_invariant_predicate_with_time_out_res(InvariantNr,State,TimeOutRes),
199		(TimeOutRes=success -> true
200		; InvariantNr = nth1_invariant(Nr),
201		b_nth1_invariant(Nr,Invariant,_UsedIds),
202		translate_bexpression_with_limit(Invariant,TS),
203		translate_span(Invariant,SpanStr),
204		(TimeOutRes=failure -> InvRes=false ; InvRes=unknown),
205		format_with_colour_nl(user_output,[red,bold],
206		'*** Invariant ~w ~w is ~w (in state with id ~w):~n ~w',[Nr,SpanStr,InvRes,ID,TS]),
207		% add_message(check_invariant,'Invariant false: ',Nr,TS),
208		(debug_mode(off) -> true
209		; translate:print_bstate(State),nl
210		)
211		% TODO: pass check dot_file_prefix or similar to analyse_invariant_for_state and call:
212		% bvisual:get_tree_from_expr(Tree, Invariant, [], State),
213		% bvisual:write_dot_graph_to_file(Tree,'invariant.dot')
214		), exit_error_scope(L,_ErrOcc,check_invariant).
215
216
217
218		check_invariant_with_time_out(ID,State) :-
219		%b_get_invariant_from_machine(Invariant),
220		b_invariant_number_list(InvList), % ensures operation caching can be applied
221		% TO DO: we could just get unproven invariants; unless we are in an initial state
222		check_invariant_predicate_with_time_out(ID,InvList,State).
223
224
225		check_invariant_predicate_with_time_out(ID,Invariant,State) :-
226		(check_invariant_predicate_with_time_out_res(Invariant,State,TimeOutRes)
227		-> check_time_out_res(TimeOutRes,ID)).
228
229		check_invariant_predicate_with_time_out_res(b(truth,_,_),_State,TimeOutRes) :- !, % only typing in invariant
230		TimeOutRes = success.
231		check_invariant_predicate_with_time_out_res(Invariant,State,TimeOutRes) :-
232		set_error_context(checking_invariant),
233		preferences:get_computed_preference(debug_time_out,DebugTimeOut),
234		call_cleanup(
235		(time_out_with_enum_warning_one_solution_no_new_error_scope(
236		b_interpreter:check_invariant_predicate_aux(Invariant,State ),
237		DebugTimeOut,TimeOutRes)
238		-> true
239		; TimeOutRes = failure),
240		clear_error_context).
241
242		% process typed predicates, lists and special invariant(Nr) terms
243		check_invariant_predicate_aux(nth1_invariant(Nr),State) :- !,
244		(get_preference(try_operation_reuse,false)
245	?	-> check_nth1_invariant(Nr,State)
246	?	; \+ b_operation_cache:check_invariant_violated_cache(Nr,State) % will call check_nth1_invariant if necessary
247		% note : for performance it is important that the State is prepared but not expanded
248		% (e.g. it should be expanded_const_and_vars with the info field containing the packed state)
249		).
250		check_invariant_predicate_aux([],_) :- !.
251		check_invariant_predicate_aux([H|T],State) :- !,
252	?	check_invariant_predicate_aux(H,State),
253	?	check_invariant_predicate_aux(T,State).
254		check_invariant_predicate_aux(Invariant,State) :-
255		b_test_boolean_expression_for_ground_state(Invariant,[],State,'INVARIANT',0).
256
257		% check the nth invariant
258		check_nth1_invariant(Nr,State) :-
259		if(b_nth1_invariant(Nr,Invariant,_UsedIds),
260	?	b_test_boolean_expression_for_ground_state(Invariant,[],State,'INVARIANT',Nr), % add Nr to call_stack
261		add_internal_error('Invariant does not exist:',Nr)).
262
263
264		check_time_out_res(time_out,ID) :- !,
265		format('**** TIMEOUT during invariant evaluation in state ~w!~n',[ID]),
266		assert_time_out_for_invariant(ID),
267		fail.
268		check_time_out_res(virtual_time_out(_WARNING),ID) :- !,
269		format('**** VIRTUAL TIMEOUT during invariant evaluation in state ~w!~n',[ID]),
270		assert_time_out_for_invariant(ID),
271		fail.
272		check_time_out_res(failure,_) :- !, fail.
273		check_time_out_res(_,_).
274
275		% b_test_boolean_expression_for_ground_state:
276		% idea: check each conjunct individually; avoids multiplication of choice points between conjuncts
277
278		:- use_module(specfile,[expand_const_and_vars_to_full_store/2]).
279		b_test_boolean_expression_for_ground_state(b(Expr,_,Infos),LS,S,PredKind) :-
280		b_test_boolean_expression_for_ground_state(b(Expr,_,Infos),LS,S,PredKind,0).
281		b_test_boolean_expression_for_ground_state(b(Expr,_,Infos),LS,S,PredKind,Nr) :-
282		expand_const_and_vars_to_full_store(S,FS), % ensure we have full store
283	?	b_test_boolean_expression_for_ground_state2(Expr,Infos,LS,FS,PredKind,Nr).
284
285		b_test_boolean_expression_for_ground_state1(b(Expr,_,Infos),LS,S,Kind,Nr) :- !,
286	?	b_test_boolean_expression_for_ground_state2(Expr,Infos,LS,S,Kind,Nr).
287
288		b_test_boolean_expression_for_ground_state2(conjunct(LHS,RHS),_,LocalState,State,Kind,Nr) :- !,
289		% usually LHS is the nested conjunct and RHS atomic:
290		%it would be better to swap LHS and RHS: but does not seem to buy anything
291	?	b_test_boolean_expression_for_ground_state1(LHS,LocalState,State,Kind,Nr),
292		!, % do we need this cut; it makes partial evaluation more tricky
293	?	b_test_boolean_expression_for_ground_state1(RHS,LocalState,State,Kind,Nr).
294		% TO DO: treate lazy_let_pred ?
295		b_test_boolean_expression_for_ground_state2(BE,Infos,LS,S,Kind,Nr) :-
296	?	b_test_boolean_expression_cs(b(BE,pred,Infos),LS,S,Kind,Nr).
297
298		state_violates_invariant(ID,State) :-
299		State \== root,
300		State \= concrete_constants(_), % machine not yet initialised (cf state_corresponds_to_initialised_b_machine)
301		\+(state_satisfies_invariant_aux(ID,State)).
302
303
304		% new profiler
305		%:- use_module('../extensions/profiler/profiler.pl').
306		%:- use_module('../extensions/profiler/profiler_te.pl').
307		%:- enable_profiling_naming(b_interpreter:state_violates_assertions_aux/2,name2).
308
309		%name2(b_interpreter:state_violates_assertions_aux,_,ASSERTIONS).
310
311		%state_violates_assertions(ID,State) :-
312		% b_interpreter:state_violates_assertions_aux(ID,State).
313
314		% old profiler
315		:- use_module(runtime_profiler,[profile_single_call/3]).
316		:- use_module(bmachine,[get_assertions_from_machine/2, b_machine_has_dynamic_assertions/0, b_machine_has_static_assertions/0]).
317		state_violates_assertions(ID,State) :-
318		profile_single_call('ASSERTIONS',ID,b_interpreter:state_violates_assertions_aux(ID,State)).
319		state_violates_assertions_aux(ID,State) :-
320		b_machine_has_dynamic_assertions,
321		state_corresponds_to_initialised_b_machine(State,BState), !,
322		\+(state_satisfies_assertions(ID,dynamic,BState)).
323		state_violates_assertions_aux(ID,State) :-
324		b_machine_has_static_assertions,
325		state_corresponds_to_set_up_constants_only(State,BState),
326		\+(state_satisfies_assertions(ID,static,BState)).
327		state_satisfies_assertions(ID,Type,State) :-
328		( get_assertions_from_machine(Type,Ass) ->
329		set_error_context(checking_assertions),
330		%enter_new_error_scope(Level,checking_assertions),
331		preferences:get_computed_preference(debug_time_out,DebugTimeOut),
332		%print(checking_assertions(ID)),nl,
333		time_out_with_enum_warning_one_solution(
334		b_test_list_of_boolean_expression_for_ground_state(Ass,'ASSERTION ',[],State),
335		DebugTimeOut,TimeOutRes, clear_errors),
336		% TO DO: in case of a virtual time-out (cf UML-B/drone_2_error.eventb) we could try and continue with the next assertion
337		clear_error_context,
338		(nonvar(TimeOutRes),
339		(TimeOutRes == time_out, Kind='TIMEOUT' ; TimeOutRes = virtual_time_out(_), Kind = 'Virtual TIMEOUT')
340		-> format('~n*** ~w during assertion checking for state id ~w!~n',[Kind,ID]),
341		assert_time_out_for_assertions(ID)
342		; true
343		)
344		; true
345		).
346
347
348
349		/* ----------------------------------*/
350		/* b_test_boolean_expression */
351		/* ----------------------------------*/
352
353
354		:- type variable_id_list +--> list(type(variable_id)).
355
356		:- type boolean_expression +--> call(bsyntaxtree:check_if_typed_predicate).
357
358		% used for testing ASSERTIONS on a fully ground state
359		b_test_list_of_boolean_expression_for_ground_state(List,PredKind,LS,S) :-
360		b_test_list_of_boolean_expression_aux(List,PredKind,1,LS,S).
361
362		b_test_list_of_boolean_expression_aux([],_,_,_,_).
363		b_test_list_of_boolean_expression_aux([B1|T],PredKind,Nr,LS,S) :- %nl,print(nr(PredKind,Nr)),nl,
364	?	(b_test_boolean_expression_for_ground_state1(B1,LS,S,PredKind,Nr)
365		-> N1 is Nr+1, b_test_list_of_boolean_expression_aux(T,PredKind,N1,LS,S)
366		; silent_mode(off),
367		(critical_enumeration_warning_occured_in_error_scope -> Res='UNKNOWN'
368		; abort_error_occured_in_error_scope -> Res ='NOT-WELL-DEFINED'
369		; Res='false'),
370		ajoin([PredKind, Nr, ' is ', Res,': '],Msg),
371		add_message(b_interpreter,Msg,B1,B1), % TO DO: get just label/location?
372		fail).
373
374
375		:- use_module(b_interpreter_components).
376
377
378		:- assert_pre(b_interpreter:b_test_boolean_expression_cs(E,LS,S,_,_),
379		(bsyntaxtree:check_if_typed_predicate(E),type_check(LS,store),type_check(S,store) )).
380		:- assert_post(b_interpreter:b_test_boolean_expression_cs(_,_,_,_,_), true ).
381
382
383		% --------------------- BOOLEAN EXPRESSIONS ----------------------------
384
385		:- use_module(b_interpreter_check).
386		:- use_module(kernel_propagation, [do_not_enumerate_binary_boolean_operator/3]).
387
388		% a version where we can provide an initial call stack entry for context
389		b_test_boolean_expression_cs(E,LS,S,PredKind,Nr) :-
390		init_wait_flags_cs(E,PredKind,Nr,b_test_boolean_expression_cs,WF),
391		% TO DO: call b_trace_test_components ?
392	?	b_test_boolean_expression(E,LS,S,WF),
393	?	ground_wait_flags(WF).
394
395		init_wait_flags_cs(E,PredKind,Nr,PP,WF) :-
396		(PredKind=none -> init_wait_flags(WF,[PP])
397		; get_texpr_pos(E,Pos),
398		CallStackEntry = prob_command_context(check_pred_command(PredKind,Nr),Pos),
399		init_wait_flags_and_push_call_stack(no_wf_available,CallStackEntry,WF)
400		).
401
402
403		b_test_boolean_expression(b(Expr,_,Infos),LS,S,WF) :- !,
404		(b_interpreter_check:composed(Expr) -> empty_avl(Ai)
405		; Ai = no_avl), % simple expression: no sharing is possible: no need to register expressions
406	?	b_test_boolean_expression2(Expr,Infos,LS,S,WF,Ai,_).
407		b_test_boolean_expression(E,LS,S,WF) :- % will generate error message
408		empty_avl(Ai), b_test_boolean_expression(E,LS,S,WF,Ai,_).
409
410		:- assert_pre(b_interpreter:b_test_boolean_expression(E,LS,S,WF),
411		(nonvar(E),bsyntaxtree:check_if_typed_predicate(E),type_check(LS,store),type_check(S,store),
412		type_check(WF,wait_flag))).
413		:- assert_post(b_interpreter:b_test_boolean_expression(_,_,_,WF), type_check(WF,wait_flag)).
414
415
416		%b_test_boolean_expression(Expr,_,_,_) :- print('test: '),translate:print_bexpr(Expr),nl,print(Expr),nl,fail. %%
417
418		:- load_files(library(system), [when(compile_time), imports([environ/2])]).
419		:- if(environ(prob_debug_watch_flag,true)).
420		b_test_boolean_expressiond(b(Expr,_,Infos),LS,S,WF,Ai,Ao) :- !,
421		b_test_boolean_expression2(Expr,Infos,LS,S,WF,Ai,Ao).
422		b_test_boolean_expression(Expr,LS,S,WF,Ai,Ao) :- !,
423		(waitflag0_is_set(WF)
424		-> debug:watch(300,b_interpreter:b_test_boolean_expressiond(Expr,LS,S,WF,Ai,Ao))
425		; debug:watch_det(300,b_interpreter:b_test_boolean_expressiond(Expr,LS,S,WF,Ai,Ao)) ).
426		:- else.
427		b_test_boolean_expression(b(Expr,Type,Infos),LS,S,WF,Ai,Ao) :- !,
428		(preference(smt_supported_interpreter,true)
429		-> b_test_boolean_expression2(Expr,Infos,LS,S,WF,Ai,Ao),
430		get_wait_flag1(smt_call,WF,BeforeEnumWF),
431		gensym:gensym(smt_assertion_name,Symbol),
432		smt_add_predicate(BeforeEnumWF,b(Expr,Type,Infos),LS,S,Symbol)
433		;
434	?	b_test_boolean_expression2(Expr,Infos,LS,S,WF,Ai,Ao)).
435		:- endif.
436		b_test_boolean_expression(E,LS,S,WF,Ai,Ao) :-
437		add_internal_error('Boolean expression not properly wrapped: ',
438		b_test_boolean_expression(E,LS,S,WF,Ai,Ao)),
439		b_test_boolean_expression2(E,[],LS,S,WF,Ai,Ao).
440
441
442		b_test_boolean_expression2(truth,_,_,_,_WF,Ai,Ao) :- !,Ai=Ao.
443		b_test_boolean_expression2(falsity,_,_,_,_WF,_Ai,_Ao) :- !,fail.
444		b_test_boolean_expression2(negation(BExpr),_,LocalState,State,WF,Ai,Ao) :- !,
445	?	b_not_test_boolean_expression(BExpr,LocalState,State,WF,Ai,Ao).
446		b_test_boolean_expression2(conjunct(LHS,RHS),_,LocalState,State,WF,Ai,Ao) :- !,
447	?	b_test_boolean_expression(LHS,LocalState,State,WF,Ai,Aii),
448	?	b_test_boolean_expression(RHS,LocalState,State,WF,Aii,Ao).
449		b_test_boolean_expression2(implication(LHS,RHS),Info,LocalState,State,WF,Ai,Ao) :-
450		%b_compiler:b_compile(LHS,[],LocalState,State,CLHS), % this slows down Cruise benchmark from 3.75 s to 4.3
451		!,
452	?	b_test_implication(LHS,RHS,Info,LocalState,State,WF,Ai,Ao).
453		b_test_boolean_expression2(equivalence(LHS,RHS),_,LocalState,State,WF,Ai,Ao) :- !,
454	?	b_test_equivalence(LHS,RHS,LocalState,State,WF,Ai,Ao).
455		b_test_boolean_expression2(disjunct(LHS,RHS),Info,LocalState,State,WF,Ai,Ao) :- !,
456		% TO DO: normalise disjunct first ?
457		copy_wf_start(WF,disjunct,CWF),
458	?	if(b_check_boolean_expression(LHS,LocalState,State,CWF,PredRes,Ai,Aii),
459		% we can check lhs
460	?	if(b_interpreter_check:b_check_boolean_expression0(pred_false,PredRes,RHS,LocalState,State,CWF,RR,Aii,Ao),
461		( /* we can also check rhs */
462	?	b_interpreter_check:disjoin(PredRes,RR,pred_true,LHS,RHS,WF),
463		copy_wf_finish(WF,CWF)
464		),
465		(
466		Ao=Aii,
467		copy_wf_finish(WF,CWF),
468		imply_test_boolean_expression(PredRes,pred_false,RHS,LocalState,State,WF,Aii),
469		perfmessagecall(choice_point,reification_of_disjunction_rhs_failed,translate:print_bexpr(RHS),Info),
470		enumerate_bool(PredRes,15,WF)
471		)
472		),
473		% we cannot check lhs
474		if((always_well_defined(RHS),
475		b_check_boolean_expression(RHS,LocalState,State,CWF,PredRes,Ai,Aii)),
476		(
477		Ao=Aii,
478		copy_wf_finish(WF,CWF),
479		imply_test_boolean_expression(PredRes,pred_false,LHS,LocalState,State,WF,Aii),
480		perfmessagecall(choice_point,reification_of_disjunction_lhs_failed,translate:print_bexpr(LHS),Info),
481		enumerate_bool(PredRes,15,WF)
482		),
483		% we cannot check neither lhs nor rhs:
484		(Ai=Ao,
485		get_priority_of_boolean_expression2(disjunct(LHS,RHS),StartPrio),
486		%get_wait_flag(Prio,disjunct,WF,WF2),
487		get_binary_choice_wait_flag_exp_backoff(StartPrio,disjunct,WF,WF2),
488		% be sure that e.g. for (x=2 or x=3) both branches will be tested once deterministic propagation is over
489		%print(prio(Prio)), print(' : '),print_bexpr(LHS), print(' or '), print_bexpr(RHS),nl,
490		perfmessagecall(choice_point,reification_of_disjunction_failed,translate:print_bexpr(b(disjunct(LHS,RHS),pred,Info)),Info),
491		b_test_disjunction(LHS,RHS,LocalState,State,WF,WF2,Ai)
492		)
493		)
494		).
495		b_test_boolean_expression2(exists(Parameters,RHS),Infos,LocalState,State,WF,Ai,Ao) :- !,Ai=Ao,
496	?	b_test_exists(Parameters,RHS,Infos,LocalState,State,WF).
497		%b_test_boolean_expression2(forall(PARS,LHS,RHS),_Inf,LocalState,State,WF) :-
498		% PARS = [b(identifier(R1),integer,_),b(identifier(R2),integer,_)],
499		% LHS = b(conjunct(b(conjunct(MEM1,MEM2),pred,_I1),NEQ),pred,_I2),
500		% NEQ = b(not_equal(b(identifier(RR1),integer,_I3),b(identifier(RR2),integer,_I4)),pred,_I5),
501		% (RR1=R1, RR2=R2 ; RR1=R2, RR2=R1),
502		% MEM1 = b(member(b(identifier(RRR1),integer,_),b(SET,set(integer),_)),pred,_),
503		% MEM2 = b(member(b(identifier(RRR2),integer,_),b(SET,set(integer),_)),pred,_),
504		% (RRR1=R1, RRR2=R2 ; RRR1=R2, RRR2=R1),
505		% /* TO DO: check that RHS is symmetric ! */ /* TO DO : generalize symmetry breaking */
506		% !, % print(symmetry_breaking_forall(R1,R2)),nl,
507		% GT = b(less(b(identifier(R1),integer,_I3),b(identifier(R2),integer,_I4)),pred,_I5),
508		% NewLHS = b(conjunct(b(conjunct(MEM1,MEM2),pred,_I1),GT),pred,_I2),
509		% b_test_boolean_expression2(forall(PARS,NewLHS,RHS),_Inf,LocalState,State,WF).
510		b_test_boolean_expression2(forall(Parameters,LHS,RHS),Infos,LocalState,State,WF,Ai,Ao) :- !,Ai=Ao,
511		/* !ID.(LHS => RHS) */
512		% print_message(forall(Parameters,LHS,RHS)),
513		% get_wait_flag0(WF,WF0), when(nonvar(WF0),
514	?	b_for_all(Parameters,Infos,LHS,RHS,LocalState,State,WF). %).
515		b_test_boolean_expression2(let_predicate(Ids,AssignmentExprs,Pred),Infos,LocalState,State,WF,Ai,Ao) :- !,
516		Ai=Ao, % any expression inside the LET cannot be safely reused
517		(is_truth(Pred)
518		-> % useless let, only sense of computations below is in detecting WD errors
519		get_enumeration_starting_wait_flag(useless_let_predicate(Ids),WF,ESWF),
520		when(nonvar(ESWF),set_up_localstate_for_let(Ids,_,AssignmentExprs,LocalState,State,_LetState,WF))
521	?	; set_up_localstate_for_let(Ids,ParaValues,AssignmentExprs,LocalState,State,LetState,WF),
522		opt_push_wait_flag_call_stack_quantifier_info(WF,let_quantifier,Ids,ParaValues,Infos,WF2),
523	?	b_test_boolean_expression(Pred,LetState,State,WF2)). % we could pass Ai in if Ids fresh
524
525		b_test_boolean_expression2(lazy_let_pred(Id,AssignmentExpr,Expr),_I,LocalState,State,WF,Ai,Ao) :- !,
526		add_lazy_let_id_and_expression(Id,AssignmentExpr,LocalState,State,NewLocalState,WF,Ai),
527	?	b_test_boolean_expression(Expr,NewLocalState,State,WF,Ai,Ao). % we could use Ai,Ao version as lazy lets never interfere with each other and never invalidate existing expressions
528		b_test_boolean_expression2(lazy_lookup_pred(Id),_Info,LocalState,_State,WF,Ai,Ao) :- !, Ai=Ao,
529		lookup_value_for_existing_id_wf(Id,LocalState,(Trigger,Value),WF), % should normally only occur in LocalState; value introduced by lazy_let
530		(Trigger,Value) = (pred_true,pred_true). % force evaluation
531		b_test_boolean_expression2(value(PredVal),_Info,_LocalState,_State,_WF,Ai,Ao) :- !, % this can occur when lazy_lookup_pred gets compiled by b_compiler
532		is_pred_true(PredVal),Ai=Ao.
533		b_test_boolean_expression2(Pred,Info,LocalState,State,WF,Ai,Ao) :-
534		% TO DO: we could put some of the operators into the Ai store (comparison operators)
535	?	b_interpreter_check:register_predicate(Pred,Info,pred_true,Reused,Ai,Ao),
536		(Reused==true
537		-> %% print('REUSED: '), translate:print_bexpr(Pred),nl
538		true
539	?	; b_test_atomic_boolean_expression2(Pred,Info,LocalState,State,WF)).
540
541		:- block is_pred_true(-).
542		is_pred_true(X) :- (X=pred_true -> true ; X=pred_false -> fail ; add_internal_error('Illegal call: ',is_pred_true(X)),fail).
543		:- block is_pred_false(-).
544		is_pred_false(X) :- (X=pred_false -> true ; X=pred_true -> fail ; add_internal_error('Illegal call: ',is_pred_false(X)),fail).
545
546
547		% we could simply call disjunct(NegLHS,RHS) ?
548		% A => B has more of a feeling of a passive constraint than A or B
549		% hence we use a lower priority here for enumerate_bool below and do not
550		% try to reify rhs if lhs reification failed (but maybe we should)
551		b_test_implication(LHS,RHS,_Info,LocalState,State,WF,Ai,Ao) :-
552		copy_wf_start(WF,implication,CWF),
553	?	if(b_check_boolean_expression(LHS,LocalState,State,CWF,PredRes,Ai,Aii),
554		%% print('checking => '), print_bexpr(LHS), print(' '), print(PredRes),nl,
555		%% The following improves constraint propagation; but can be tricky with undefinedness
556		if((var(PredRes),always_well_defined(RHS),
557		b_check_boolean_expression(RHS,LocalState,State,CWF,RHSPredRes,Aii,Ao)),
558		(/* also propagate from right to left */
559	?	b_interpreter_check:imply_true(PredRes,RHSPredRes),
560		perfmessage_bexpr(good(reify),'Fully reified implication with LHS: ',LHS),
561	?	copy_wf_finish(WF,CWF)
562		),
563		( Aii=Ao,
564	?	copy_wf_finish(WF,CWF),
565	?	imply_test_boolean_expression(PredRes,pred_true,RHS,LocalState,State,WF,Aii),
566		(nonvar(PredRes) -> true
567		; performance_monitoring_on,
568		\+always_well_defined(RHS) -> perfmessage_bexpr(reify,'Cannot reify RHS of => due to WD condition, creating choice point:',RHS)
569		; perfmessage_bexpr(reify,'Cannot reify RHS of =>, creating choice point:',RHS)
570		),
571		enumerate_bool(PredRes,10000,WF) % lower priority than disjunction (15); we could use last_finite_priority ?
572		)
573		),
574		( Ai=Ao,
575		perfmessage_bexpr(reify,'Cannot reify LHS of =>, creating binary choice point:',LHS),
576		get_binary_choice_wait_flag(implication,WF,WF2),
577		block_test_implication(LHS,RHS,LocalState,State,WF,WF2)
578		)
579		).
580
581		% ------------
582
583		:- discontiguous b_test_atomic_boolean_expression2/5.
584		%b_test_atomic_boolean_expression2(Expr,T,LocalState,State,WF) :- print(eval(Expr,T)),nl,fail.
585		b_test_atomic_boolean_expression2(partition(LHS,RHS),_,LocalState,State,WF) :- !,
586		b_compute_expression(LHS,LocalState,State,SV1,WF), %print(lhs(SV1)),nl,
587		l_compute_expression(RHS,LocalState,State,SV2,WF), % RHS is Prolog list of expressions
588	?	kernel_call_predicate(partition_wf(SV1,SV2,WF),kernel_objects,WF,partition(LHS,RHS)).
589		b_test_atomic_boolean_expression2(member(TElem,TSet),_,LocalState,State,WF) :- !,
590	?	b_test_member_expression(TElem,TSet,LocalState,State,WF).
591		b_test_atomic_boolean_expression2(not_member(TElem,TSet),Info,LocalState,State,WF) :- !,
592		get_texpr_expr(TSet,Set),
593	?	b_test_notmember_expression(Set,TElem,TSet,Info,LocalState,State,WF).
594		b_test_atomic_boolean_expression2(freetype_case(Freetype,Case,Expr),_,LocalState,State,WF) :-
595		!,equal_object_wf(Value,freeval(Freetype,Case,_),b_test_atomic_boolean_expression2,WF),
596		b_compute_expression(Expr,LocalState,State,Value,WF). % NOT COVERED (16)
597		b_test_atomic_boolean_expression2(finite(SetExpr),_,LocalState,State,WF) :-
598		!, b_compute_expression(SetExpr,LocalState,State,Value,WF),
599		kernel_call_predicate(is_finite_set_wf(Value,WF),kernel_objects,WF,finite(SetExpr)).
600		/* Extension for Kodkod */
601		b_test_atomic_boolean_expression2(kodkod(ProblemId,_),_,LocalState,State,WF) :-
602		!,get_wait_flag1(kodkod_call,WF,WF0),
603		kodkod_request(ProblemId,pos,LocalState,State,WF0). % NOT COVERED (17)
604		%b_test_atomic_boolean_expression2(equal(Arg1,Arg2),_,LocalState,State,WF) :- get_texpr_type(Arg1,integer),!,
605		% b_compute_expression(Arg1,LocalState,State,ExprRes,WF),
606		% b_compute_expression(Arg2,LocalState,State,ExprRes,WF). /* avoids one extra variable compared to code below + could fail earlier ; but problem as b_compute_expression still uses = in some places */
607
608		:- include(b_arithmetic_expressions).
609		%The following clause improves Nqueens performance by about 50 %; by avoiding intermediate variables
610		% TO DO: do the same for >, <, >= ...
611		b_test_atomic_boolean_expression2(equal(Arg1,Arg2),Info,LocalState,State,WF) :- !,
612	?	b_test_atomic_equal_boolean_expression(Arg1,Arg2,Info,LocalState,State,WF).
613		b_test_atomic_boolean_expression2(not_equal(Arg1,Arg2),Info,LocalState,State,WF) :- !,
614	?	b_test_atomic_not_equal_boolean_expression(Arg1,Arg2,Info,LocalState,State,WF).
615		b_test_atomic_boolean_expression2(less_equal(Arg1,Arg2),_Info,LocalState,State,WF) :-
616		%get_texpr_type(Arg1,integer), % type checker already checks this
617		preferences:preference(use_clpfd_solver,true),
618		!,
619	?	b_compute_arith_expression(Arg1,LocalState,State,CLPFD_Expr1,WF),
620	?	b_compute_arith_expression(Arg2,LocalState,State,CLPFD_Expr2,WF),
621		clpfd_interface:clpfd_leq_expr(CLPFD_Expr1,CLPFD_Expr2).
622		b_test_atomic_boolean_expression2(greater_equal(Arg1,Arg2),_Info,LocalState,State,WF) :-
623		%get_texpr_type(Arg1,integer), % type checker already checks this
624		preferences:preference(use_clpfd_solver,true),
625		!,
626		b_compute_arith_expression(Arg1,LocalState,State,CLPFD_Expr1,WF),
627		b_compute_arith_expression(Arg2,LocalState,State,CLPFD_Expr2,WF),
628		clpfd_interface:clpfd_leq_expr(CLPFD_Expr2,CLPFD_Expr1).
629		b_test_atomic_boolean_expression2(less(Arg1,Arg2),_Info,LocalState,State,WF) :-
630		%get_texpr_type(Arg1,integer), % type checker already checks this
631		preferences:preference(use_clpfd_solver,true),
632		!,
633	?	b_compute_arith_expression(Arg1,LocalState,State,CLPFD_Expr1,WF),
634	?	b_compute_arith_expression(Arg2,LocalState,State,CLPFD_Expr2,WF),
635		clpfd_interface:clpfd_lt_expr(CLPFD_Expr1,CLPFD_Expr2).
636		b_test_atomic_boolean_expression2(greater(Arg1,Arg2),_Info,LocalState,State,WF) :-
637		%get_texpr_type(Arg1,integer), % type checker already checks this
638		preferences:preference(use_clpfd_solver,true),
639		!,
640	?	b_compute_arith_expression(Arg1,LocalState,State,CLPFD_Expr1,WF),
641		b_compute_arith_expression(Arg2,LocalState,State,CLPFD_Expr2,WF),
642		clpfd_interface:clpfd_lt_expr(CLPFD_Expr2,CLPFD_Expr1).
643		b_test_atomic_boolean_expression2(external_pred_call(FunName,Args),Info,LocalState,State,WF) :-
644		!,
645		(do_not_evaluate_args(FunName) -> EvaluatedArgs=[]
646	?	; b_compute_expressions(Args, LocalState,State, EvaluatedArgs, WF)),
647		push_wait_flag_call_stack_info(WF,external_call(FunName,EvaluatedArgs,Info),WF2),
648	?	call_external_predicate(FunName,Args,EvaluatedArgs,LocalState,State,pred_true,Info,WF2).
649		b_test_atomic_boolean_expression2(Expression,Info,LocalState,State,WF) :-
650		preferences:preference(use_clpfd_solver,false),
651		special_binary_predicate(Expression,Module:Kernel_predicate,Arg1,T1,Arg2,T2),
652		(nonmember(contains_wd_condition,Info) -> true ; preference(disprover_mode,true)),
653		!,
654		% print('Special call: '), print_bexpr(Expression),nl, print(Kernel_predicate),print(' : '),nl,
655		%(Arg1==list_of_expressions -> b_compute_expressions ... % no longer needed
656		b_compute_expression(Arg1,LocalState,State,SV1,WF),
657		b_compute_expression(Arg2,LocalState,State,SV2,WF),
658		KernelCall =.. [Kernel_predicate,SV1,T1,SV2,T2,WF],
659		kernel_call_predicate(KernelCall,Module,WF,Expression).
660		b_test_atomic_boolean_expression2(Expression,_,LocalState,State,WF) :-
661		functor(Expression,BOP,2),
662		kernel_mappings:binary_boolean_operator(BOP,Module:Kernel_predicate,WFEnabled),!,
663		arg(1,Expression,Arg1), arg(2,Expression,Arg2),
664	?	b_compute_expression(Arg1,LocalState,State,SV1,WF), % TODO: symbolic for some BOP: <:, <<: ?
665		(binary_boolean_operator_trivially_true(BOP,SV1)
666		-> check_well_defined(Arg2,LocalState,State,WF)
667	?	; b_compute_expression(Arg2,LocalState,State,SV2,WF),
668		( WFEnabled==yes ->
669		KernelCall =.. [Kernel_predicate,SV1,SV2,WF2],
670		(do_not_enumerate_binary_boolean_operator(BOP,Arg1,Arg2) % we assume: this is only true for WFEnabled predicates
671		-> add_wait_flag_info(WF,wfx_no_enumeration,WF2)
672		; WF2=WF)
673		; KernelCall =.. [Kernel_predicate,SV1,SV2], WF2=WF % note: WF2 still used in kernel_call_predicate
674		),
675	?	kernel_call_predicate(KernelCall,Module,WF2,Expression)
676		).
677		b_test_atomic_boolean_expression2(E,Info,_LS,_S,_WF) :-
678		add_internal_error('Uncovered boolean expression: ',b(E,pred,Info)),
679		print_functor(E),nl,
680		fail.
681
682
683		binary_boolean_operator_trivially_true(subset,X) :- X==[].
684
685		check_well_defined(Arg,_LocalState,_State,_WF) :-
686		always_well_defined(Arg),!.
687		check_well_defined(Arg,LocalState,State,WF) :-
688		b_compute_expression(Arg,LocalState,State,_,WF).
689
690		%:- use_module(specfile,[animation_minor_mode/1]).
691		:- use_module(b_machine_hierarchy,[abstract_constant/2, concrete_constant/2]).
692		b_test_atomic_equal_boolean_expression(Arg1,Arg2,_Info,LocalState,State,WF) :-
693		Arg1 = b(_,integer,_), %get_texpr_type(Arg1,integer),
694		preferences:preference(use_clpfd_solver,true),!,
695		(Arg2 = b(_,integer,_) -> true ; add_internal_error('Type error in AST, not wrapped integer: ',Arg2)),
696	?	b_test_arith_equal_boolean_expression(Arg1,Arg2,LocalState,State,WF).
697		b_test_atomic_equal_boolean_expression(Arg1,Arg2,Info,LocalState,State,WF) :-
698	?	member(prob_annotation('LAMBDA-EQUALITY'),Info),
699		\+ simple_expression(Arg2),
700		is_lambda_result_id(Arg1), %get_texpr_id(Arg1,'_lambda_result_'), % ensure we have not renamed it to was_lambda_result ?
701		!, % this is an equality for the result of a lambda abstraction; only evaluate at the end
702		b_compute_expression(Arg1,LocalState,State,SV1,WF), % this is the lambda result identifier _lambda_result_
703		%get_enumeration_finished_wait_flag(WF,EWF),
704		%get_wait_flag(10000,lambda_result,WF,EWF),
705		% compute deterministic parts of Arg2 in wf0 phase: avoid computing this stuff over again
706		%print('DELAY: '), translate:print_bexpr(Arg2),nl,
707	?	kernel_waitflags:copy_wf01e_wait_flags(WF,WF2), b_compute_expression(Arg2,LocalState,State,SV2,WF2),
708		get_last_wait_flag(lambda_result,WF,EWF),
709		ground_value_check(SV2,G2),
710		when((nonvar(G2);nonvar(SV1);nonvar(EWF)),b_lambda_result_equal_boolean_expression(SV1,SV2,WF,EWF,WF2)).
711		b_test_atomic_equal_boolean_expression(Arg1,Arg2,Info,LocalState,State,WF) :-
712		(LocalState = []
713		-> true % only check if we are at the outer level
714		% (not inside a quantifier,...) or if we have CSE introduzed lazy_lets:
715		; preferences:preference(use_common_subexpression_elimination,true)
716		% TO DO: check that we have only added @nr to local state from lazy_let; ADD INFO FIELD
717		),
718		get_texpr_type(Arg1,Type1), is_set_type(Type1,SetType1),
719		% previously we required SetType1 = couple(_,_)
720		get_texpr_id(Arg1,ID),
721		% we could check: \+ get_texpr_id(Arg2,_), we do not need to treat simple equations like ID=ID2; unless for memo?
722	?	(abstract_constant(ID,_) % check if ABSTRACT_CONSTANT
723		-> Kind=abstract,
724	?	kernel_objects:max_cardinality(Type1,MaxCard1),
725		(number(MaxCard1) % check that type is large enough to warrant recursive or symbolic treatment
726		-> (MaxCard1>100 -> true ; constant_variable_marked_as_memo(ID))
727		; true)
728		; %fail,
729	?	concrete_constant(ID,_)
730		-> Kind=concrete,
731		(constant_variable_marked_as_expand(ID)
732		-> true % note: we also check for expand annotation in store (expand_closure_value),
733		% but it is useful to expand ID already here to ease checking PROPERTIES
734		; constant_variable_marked_as_memo(ID))
735		%; b_is_unused_constant(ID) -> ABSTRACT=true % TO DO: check if ID not used somewhere else in Properties ??!!
736		),
737		% in future: we may do size change analysis, or something like that to check that we have properly defined
738		% recursive function
739		debug_format(19,'Equation defining ~w constant: ~w~n',[Kind,ID]),
740		!,
741		(constant_variable_marked_as_expand(ID) -> SymArg2 = Arg2 ; mark_bexpr_as_symbolic(Arg2,SymArg2)),
742	?	b_add_constant_definition(Kind,ID,Info,Arg1,SetType1,SymArg2,LocalState,State,WF).
743		b_test_atomic_equal_boolean_expression(Arg1,Arg2,Info,LocalState,State,WF) :-
744		constants_profiling_on,
745		get_texpr_id(Arg1,ID),b_is_constant(ID), !,
746		% Note: does not yet keep track of arithmetic equalities above
747		b_compute_expression(Arg1,LocalState,State,SV1,WF),
748		push_constant_def_equality_call_stack(WF,ID,Info,WF2),
749		start_profile(ID,T1),
750		b_compute_expression(Arg2,LocalState,State,SV2,WF2),
751		get_waitflags_phase(WF,Phase),
752		stop_constant_profile(SV2,Phase,ID,[],T1), % normal constant, not symbolic, memoized or recursive
753		start_propagation_profile(ID,T2,CstL1),
754		kernel_call_predicate_equal_object_optimized(SV1,SV2,WF),
755		stop_propagation_profile(SV2,ID,T2,CstL1).
756		b_test_atomic_equal_boolean_expression(Arg1,Arg2,_Info,LocalState,State,WF) :-
757	?	b_compute_expression(Arg1,LocalState,State,SV1,WF),
758	?	b_compute_expression(Arg2,LocalState,State,SV2,WF),
759	?	kernel_call_predicate_equal_object_optimized(SV1,SV2,WF).
760
761
762
763		% treat equality ID = Symbolic Function (or relation/set)
764		b_add_constant_definition(Kind,ID,Info,Arg1,SetType1,SymArg2,LocalState,State,WF) :-
765		% observe CTRL-C: e.g., in data validation models these abstract functions can be very large and costly to compute
766	?	observe_user_interrupt_signal(computing_value_for_abstract_constant(ID),SymArg2,
767		b_add_constant_definition_aux(Kind,ID,Info,Arg1,SetType1,SymArg2,LocalState,State,WF)).
768
769		:- use_module(runtime_profiler,[start_profile/2,
770		stop_constant_profile/5, constants_profiling_on/0]).
771		b_add_constant_definition_aux(Kind,ID,_Info,Arg1,SetType1,SymArg2,LocalState,State,WF) :-
772		(preference(use_function_memoization,true), Kind=abstract ;
773		constant_variable_marked_as_memo(ID)), % description(memo) as info field using @desc memo pragma; see
774		!,
775		start_profile(ID,T1),
776		b_compute_expression(Arg1,LocalState,State,SV1,WF), % the identifier
777		(SymArg2 = b(recursive_let(TID,Body),_,_)
778		-> get_texpr_id(TID,RecID),
779		b_compute_expression(Body,[bind(RecID,RedIDVal)|LocalState],State,SV2,WF),
780		RecValue='$recursion_value'(RedIDVal), IDInfo = [recursive_memo]
781		; b_compute_expression(SymArg2,LocalState,State,SV2,WF),
782		RecValue='$no_recursion', IDInfo = [memoized]
783		),
784		get_waitflags_phase(WF,Phase), stop_constant_profile(SV2,Phase,ID,IDInfo,T1),
785		(nonvar(SV2), SV2 \= closure(_,_,_)
786		-> % value fully computed; no need to memoize
787		debug_println(19,not_memoizing(ID)),
788		kernel_call_predicate_equal_object_optimized(SV1,SV2,WF)
789		; (nonvar(SV2) -> mark_closure_as_symbolic(SV2,SV3) ; SV3=SV2),
790		memoization:register_memoization_function(ID,SV3,SetType1,RecValue,MEMOID,SV4),
791		debug_println(19,marking_for_memoization(ID,MEMOID)),
792		kernel_call_predicate_equal_object_optimized(SV1,SV4,WF)
793		).
794		b_add_constant_definition_aux(_Kind,ID,Info,Arg1,_,SymArg2,LocalState,State,WF) :-
795		start_profile(ID,T1),
796		b_compute_expression(Arg1,LocalState,State,SV1,WF), % the identifier ID
797		push_constant_def_equality_call_stack(WF,ID,Info,WF2),
798	?	b_compute_expression(SymArg2,LocalState,State,SV2,WF2),
799		(constant_variable_marked_as_expand(ID)
800		-> IDInfo = [marked_as_expand],
801		b_expand_compute_comprehension_set(SV2,Info,SV3,WF)
802		; definitely_expand_this_explicit_set(SV2) % check for a few patterns which should definitely be expanded;
803		% in case user puts a set accidentally into the ABSTRACT_CONSTANTS section
804		-> IDInfo = [automatic_expand],
805		b_expand_compute_comprehension_set(SV2,Info,SV3,WF)
806		; var(SV2) -> IDInfo = [], SV3=SV2
807		; IDInfo = [], % it is from ABSTRACT_CONSTANTS, but this info is already stored
808		mark_closure_as_symbolic(SV2,SV3)
809		),
810		get_waitflags_phase(WF,Phase), stop_constant_profile(SV3,Phase,ID,IDInfo,T1),
811		start_propagation_profile(ID,T2,CstL1),
812		kernel_call_predicate_equal_object_optimized(SV1,SV3,WF),
813		% profile propagation time and what constants are grounded
814		stop_propagation_profile(SV3,ID,T2,CstL1).
815
816		push_constant_def_equality_call_stack(WF,ID,Pos,WF2) :-
817		(constants_profiling_on
818		-> push_wait_flag_call_stack_info(WF,
819		id_equality_evaluation(ID,constant,Pos),WF2)
820		; WF2=WF).
821
822		start_propagation_profile(ID,T1,CstL1) :-
823		(constants_profiling_on -> findall(Cst1,det_solution_for_constant_was_stored(Cst1),CstL1) ; CstL1=[]),
824		start_profile(ID,T1).
825		stop_propagation_profile(SV3,ID,T1,CstL1) :-
826		(constants_profiling_on
827		-> findall(Cst2,det_solution_for_constant_was_stored(Cst2),L2),
828		append(CstL1,New,L2), debug_format(9,'Propagation of value for ~w instantiated ~w~n',[ID,New]),
829		IDInfo2 = [instantiates(New)]
830		; IDInfo2 = []),
831		stop_constant_profile(SV3,propagate_value,ID,IDInfo2,T1).
832
833		% treat not(Arg1 = Arg2) predicates
834		b_test_atomic_not_equal_boolean_expression(Arg1,Arg2,_Info,LocalState,State,WF) :-
835		get_texpr_type(Arg1,boolean),!, % special treatment : not_equal_object has no type information
836		b_compute_expression(Arg1,LocalState,State,B1,WF),
837		b_compute_expression(Arg2,LocalState,State,B2,WF),
838		negate(B1,B2). % from bool_pred
839		b_test_atomic_not_equal_boolean_expression(Arg1,Arg2,_Info,LocalState,State,WF) :-
840		get_texpr_type(Arg1,integer),
841		preferences:preference(use_clpfd_solver,true),
842		!,
843		% Note: calling b_compute_arith_expression will also instantiate a variable to at least the int(_) skeleton; thereby enabling propagation
844		% this is potentially better than calling the default versions of the predicates, which may wait until the int(_) skeleton is set up before propagation
845	?	b_compute_arith_expression(Arg1,LocalState,State,CLPFD_Expr1,WF),
846	?	b_compute_arith_expression(Arg2,LocalState,State,CLPFD_Expr2,WF),
847		clpfd_interface:clpfd_neq_expr(CLPFD_Expr1,CLPFD_Expr2).
848		b_test_atomic_not_equal_boolean_expression(Arg1,Arg2,_Info,LocalState,State,WF) :-
849	?	b_compute_expression_symbolic(Arg1,LocalState,State,SV1,WF),
850	?	b_compute_expression_symbolic(Arg2,LocalState,State,SV2,WF),
851		kernel_call_predicate_not_equal_object(SV1,SV2,WF,not_equal(Arg1,Arg2)).
852		% Note: symbolic case occurs for symbolic abstract constants f when using DOUBLE_EVALUATION
853		% in the evaluation view which are defined by f = %x... when checking f /=
854
855		% a version of b_compute_expression which does not try to expand comprehension sets
856		% TODO: deal with other constructs which merit symbolic treatment; union of comprehension sets, ...
857		% (see line 147 in AMASS_mchs/oriented_abscissa.mch)
858		b_compute_expression_symbolic(Arg,LocalState,State,Val,WF) :-
859		(Arg = b(comprehension_set(PP,CC),_,InfoCS) % second arg is a comprehension set;
860		-> % print(symbolic(PP)),nl,
861	?	b_compute_comprehension_set_symbolic(PP,CC,InfoCS,LocalState,State,Val,WF)
862	?	; b_compute_expression(Arg,LocalState,State,Val,WF)
863		).
864		% ditto for already de-constructed b/3 expression:
865		b_compute_expression2_symbolic(comprehension_set(PP,CC),_,InfoCS,LocalState,State,Val,WF) :- !,
866		b_compute_comprehension_set_symbolic(PP,CC,InfoCS,LocalState,State,Val,WF).
867		b_compute_expression2_symbolic(Arg,Type,Info,LocalState,State,Val,WF) :-
868		b_compute_expression2(Arg,Type,Info,LocalState,State,Val,WF).
869
870		simple_expression(b(A,_,_)) :- simple_expression_aux(A).
871		simple_expression_aux(boolean_true).
872		simple_expression_aux(boolean_false).
873		simple_expression_aux(empty_set).
874		simple_expression_aux(empty_sequence).
875		simple_expression_aux(integer(_)).
876		simple_expression_aux(max_int).
877		simple_expression_aux(min_int).
878		simple_expression_aux(string(_)).
879		simple_expression_aux(value(_)).
880
881
882		is_lambda_result_id(b(identifier('_lambda_result_'),_,_)).
883		% at the moment we only detect those identifiers; the info field is currently not updated for _was_lambda_result_
884		% and not available in other treatmens of _lambda_result_ (in b_enumerate)
885		%is_lambda_result_id(b(identifier(X),_,Info)) :-
886		% memberchk(lambda_result,Info).
887		% (X=='_lambda_result_' -> (memberchk(lambda_result,Info) -> true ; format('~n*** _lambda_result_ without info: ~w~n~N',[Info])) ; memberchk(lambda_result,Info)).
888
889		%:- block b_lambda_result_equal_boolean_expression(-,?,?, -,?). % we now use when above
890		% only compute lambda result when finished finding domain element, i.e., _EWF is grounded
891		b_lambda_result_equal_boolean_expression(SV1,SV2,WF,EWF,WF2) :-
892		kernel_call_predicate_equal_object_optimized(SV1,SV2,WF),
893		% print(' LAMBDA : '), print((SV1,_EWF)),nl,
894		% the inner waitflags are for evaluating the lambda_result Expression; unless there is a WD issue this should
895		% never fail; we can delay the enumeration as much as possible
896		% NOTE: even if SV2 is ground, Arg2 may not be (e.g., if Arg2 = prj2(..,..)(NotGr,Ground))
897	?	blocking_ground_copied_wait_flags(WF2,EWF). % without when we will ground WF0 which is shared with outer WF-store
898		:- block blocking_ground_copied_wait_flags(?,-).
899		blocking_ground_copied_wait_flags(WF2,_) :-
900	?	ground_constraintprop_wait_flags(WF2). % do not ground EF flag, as shared with outer WF and WF2 is copied
901
902		% TO DO: add avl_set+closure expansion
903		%b_test_member_expression(Expr,El,_Set,_LocalState,_State,_WF) :-
904		% print('test member: '),print_bexpr(Expr),nl,fail.
905		b_test_member_expression(TElem,b(Set,Type,Info),LocalState,State,WF) :-
906	?	b_test_member_expression2(Set,Type,Info,TElem,LocalState,State,WF).
907
908		% new profiler
909		%:- use_module('../extensions/profiler/profiler.pl').
910		%:- use_module('../extensions/profiler/profiler_te.pl').
911		%:- enable_profiling(b_test_member_expression2/7).
912
913		% old profiler
914		%:- use_module(covsrc(hit_profiler)).
915
916		b_test_member_expression2(comprehension_set(Par,Cond),_Type,_Info,El,LocalState,State,WF) :-
917		% used to call in next clause below: b_generate_closure_if_necessary(Par,Cond,LocalState,State,SetValue,WF) /* will not expand closure */
918		/* optimized case for dealing with comprehension_set ; however, does not seem to buy anything over older version with b_generate_closure_if_necessary in test 1079 */
919		/* new version buys about 6 % for {x| x:1..400000 & x:{n|n >= 9000 & n<= 600000 & n mod 100 = 0}} (Sep 3 2014) */
920		set_up_typed_localstate(Par,ValueList,_TypedVals,LocalState,NewLocalState,positive),
921		!,
922		convert_list_into_pairs(ValueList,ElementVal),
923		b_compute_expression(El,LocalState,State,ElementVal,WF),
924		b_test_boolean_expression(Cond,NewLocalState,State,WF).
925		b_test_member_expression2(SymbolicSetConstant,_Type,_Info,El,LocalState,State,WF) :-
926		%hit_profiler:add_profile_hit(SymbolicSetConstant),
927		cst_in_boolean_type(SymbolicSetConstant,Module:Kernel_predicate),!, % two cases : string_set and integer_set
928		b_compute_expression(El,LocalState,State,ElValue,WF),
929		functor(KernelCall,Kernel_predicate,2),
930		arg(1,KernelCall,ElValue),
931		arg(2,KernelCall,WF),
932		% print_message(cst_in_boolean_type_call(KernelCall)),
933		kernel_call_predicate(KernelCall,Module,WF,SymbolicSetConstant). % should be member(... SymbolicSetConstant)
934		b_test_member_expression2(Expression,_Type,Info,El,LocalState,State,WF) :-
935		functor(Expression,BOP,2),
936		binary_in_boolean_type(BOP,Module:Kernel_predicate),!,
937		b_compute_expression(El,LocalState,State,ElValue,WF),
938		arg(1,Expression,Arg1),arg(2,Expression,Arg2),
939		(binary_in_definitely_true(BOP,ElValue)
940		-> % no need to compute arguments; unless required for WD:
941		check_well_defined(Arg1,LocalState,State,WF),
942		check_well_defined(Arg2,LocalState,State,WF)
943		; b_compute_expression(Arg1,LocalState,State,SV1,WF),
944	?	b_compute_expression(Arg2,LocalState,State,SV2,WF),
945		opt_push_wait_flag_call_stack_info(WF,b_operator_call(member,[ElValue,b_operator(BOP,[SV1,SV2])],Info),WF2),
946		% for constant profiling: we could catch partial/total_fun checks here translate:print_bexpr(El),nl,translate:print_bexpr(b(Expression,_Type,Info)),nl,nl,
947	?	binary_in_kernel_call(Module,Kernel_predicate,ElValue,SV1,SV2,WF2,Expression)
948		).
949		b_test_member_expression2(Expression,_Type,Info,El,LocalState,State,WF) :-
950		functor(Expression,UnOP,1),
951		unary_in_boolean_type(UnOP,Module:Kernel_predicate),!,
952		b_compute_expression(El,LocalState,State,ElValue,WF),
953		arg(1,Expression,Arg1),
954		(unary_in_definitely_true(UnOP,ElValue)
955		-> % no need to compute arguments; unless required for WD:
956		check_well_defined(Arg1,LocalState,State,WF)
957	?	; b_compute_expression(Arg1,LocalState,State,SV1,WF),
958		opt_push_wait_flag_call_stack_info(WF,b_operator_call(member,[ElValue,b_operator(UnOP,[SV1])],Info),WF2),
959	?	unary_in_kernel_call(Module,Kernel_predicate,ElValue,SV1,WF2,Expression)
960		).
961		b_test_member_expression2(SetExpression,Type,Info,El,LocalState,State,WF) :-
962	?	b_compute_expression2(SetExpression,Type,Info,LocalState,State,SetValue,WF),
963		(always_well_defined_or_disprover_mode(El)
964		-> SetValue \== [] % if we have the empty set: check_element will always fail
965		; true % we could check SetValue \== [] if find_abort_values=false ??
966		),
967	?	b_compute_expression(El,LocalState,State,Element,WF),
968		Span = El, % Info is quite often the empty list
969		(not_invertible(El) % then no sense in setting up member constraint f(...) : SetValue ;
970		% we cannot used the info anyway; but we could enumerate
971		-> % we wait until Element is fully known before doing the check
972		ground_value_check(Element,GrEl),
973		when(nonvar(GrEl),kernel_call_predicate_check_element_of_wf(Element,SetValue,WF,Span))
974	?	; kernel_call_predicate_check_element_of_wf(Element,SetValue,WF,Span)).
975
976		:- use_module(external_functions,[external_fun_can_be_inverted/1]).
977		not_invertible(b(E,_,_)) :- not_inv_aux(E).
978		not_inv_aux(external_function_call(FunName,_Args)) :- \+ external_fun_can_be_inverted(FunName).
979		% TO DO: capture other cases like function applications
980		% TO DO: also do this in b_interpreter_check ?
981		% TO DO: We should compute this information in ast_cleanup; e.g., what if we do STRING_TO_INT(s)+1 : SET
982
983		% TO DO: >>> 2:{x,v} --> special case for set_extension([b(identifier(x),integer,[nodeid(none)]),b(identifier(v),integer,[nodeid(none)])]) --> 2=x or 2=v --> evaluate [x,v] -> sort and then use list member (or should b_ast_cleanup do this) ?
984
985		:- use_module(kernel_lists,[not_element_of_list_wf/3]).
986		b_test_notmember_expression(set_extension(Ex),El,_Set,_,LocalState,State,WF) :- !,
987		b_compute_expressions(Ex,LocalState,State,ExValueList,WF),
988		b_compute_expression(El,LocalState,State,ElementVal,WF),
989		not_element_of_list_wf(ElementVal,ExValueList,WF).
990		b_test_notmember_expression(SymbolicSetCst,El,_Set,_,LocalState,State,WF) :-
991		kernel_mappings:cst_not_in_boolean_type(SymbolicSetCst,Module:Kernel_predicate),!,
992		b_compute_expression(El,LocalState,State,ElValue,WF),
993		functor(KernelCall,Kernel_predicate,1),
994		arg(1,KernelCall,ElValue),
995		% debug_print(cst_not_in_boolean_type(9,KernelCall)),
996		kernel_call_predicate(KernelCall,Module,WF,SymbolicSetCst).
997		b_test_notmember_expression(Expression,El,_Set,Info,LocalState,State,WF) :-
998		functor(Expression,BOP,2),
999		kernel_mappings:binary_not_in_boolean_type(BOP,Module:Kernel_predicate),!,
1000		b_compute_expression(El,LocalState,State,ElValue,WF),
1001		\+ binary_in_definitely_true(BOP,ElValue),
1002		arg(1,Expression,Arg1),arg(2,Expression,Arg2),
1003		b_compute_expression(Arg1,LocalState,State,SV1,WF),
1004		b_compute_expression(Arg2,LocalState,State,SV2,WF),
1005		% KernelCall =.. [Kernel_predicate,ElValue,SV1,SV2,WF],
1006		opt_push_wait_flag_call_stack_info(WF,b_operator_call(not_member,[ElValue,b_operator(BOP,[SV1,SV2])],Info),WF2),
1007	?	kernel_call_predicate3(Kernel_predicate,ElValue,SV1,SV2,Module,WF2,Expression).
1008		b_test_notmember_expression(Expression,El,_Set,Info,LocalState,State,WF) :-
1009		functor(Expression,UnOP,1),
1010		unary_not_in_boolean_type(UnOP,Module:Kernel_predicate),!,
1011		b_compute_expression(El,LocalState,State,ElValue,WF),
1012		\+ unary_in_definitely_true(UnOP,ElValue),
1013		arg(1,Expression,Arg1),
1014		b_compute_expression(Arg1,LocalState,State,SV1,WF),
1015		%KernelCall =.. [Kernel_predicate,ElValue,SV1,WF],
1016		%kernel_call_predicate(KernelCall,Module,WF,Expression).
1017		opt_push_wait_flag_call_stack_info(WF,b_operator_call(not_member,[ElValue,b_operator(UnOP,[SV1])],Info),WF2),
1018		kernel_call_predicate2(Kernel_predicate,ElValue,SV1,Module,WF2,Expression).
1019		b_test_notmember_expression(Expr,Elem,Set,_Info,LocalState,State,WF) :-
1020		(Expr=comprehension_set(Par,Cond)
1021		-> b_generate_closure_if_necessary(Par,Cond,LocalState,State,SetValue,WF) /* will not expand closure */
1022		; b_compute_expression(Set,LocalState,State,SetValue,WF)
1023		),
1024		(SetValue == []
1025		-> /* nothing can be member of empty set */
1026		check_well_defined(Elem,LocalState,State,WF)
1027		% we could disable this check if find_abort_values=true
1028		; b_compute_expression(Elem,LocalState,State,ElemValue,WF),
1029		%kernel_call_predicate2(not_element_of_wf,ElemValue,SetValue,kernel_objects,WF,Expr)
1030		%kernel_call_predicate(not_element_of_wf(ElemValue,SetValue,WF),kernel_objects,WF,Expr)
1031		kernel_call_predicate_not_element_of_wf(ElemValue,SetValue,WF)
1032		).
1033
1034		:- block block_test_implication(?,?,?,?,?,-).
1035		block_test_implication(LHS,RHS,LocalState,State,WF,_WF2) :-
1036	?	b_test_inner_boolean_expression(LHS,LocalState,State,WF),
1037		b_test_inner_boolean_expression(RHS,LocalState,State,WF).
1038		block_test_implication(LHS,_RHS,LocalState,State,WF,_WF2) :-
1039		b_not_test_inner_boolean_expression(LHS,LocalState,State,WF).
1040
1041
1042		b_test_equivalence(LHS,RHS,LocalState,State,WF,Ai,Ao) :-
1043		copy_wf_start(WF,equivalence,CWF),
1044		if(b_check_boolean_expression(LHS,LocalState,State,CWF,PredRes,Ai,Aii),
1045	?	(b_check_test_equivalence(PredRes,LHS,RHS,LocalState,State,CWF,Aii,Ao),
1046		copy_wf_finish(WF,CWF)),
1047		(% check LHS fails, We could check if RHS can be checked with b_check_boolean_expression
1048		Ai=Ao, get_binary_choice_wait_flag(equivalence,WF,WF2),
1049		b_enum_test_equivalence(LHS,RHS,LocalState,State,WF,WF2,Ai))).
1050		b_not_test_equivalence(LHS,RHS,LocalState,State,WF,Ai,Ao) :-
1051		copy_wf_start(WF,not_equivalence,CWF),
1052		if(b_check_boolean_expression(LHS,LocalState,State,CWF,PredRes,Ai,Aii),
1053		(negate(PredRes,NegPredRes), % from bool_pred
1054		b_check_test_equivalence(NegPredRes,LHS,RHS,LocalState,State,CWF,Aii,Ao),
1055		copy_wf_finish(WF,CWF)),
1056		(% check LHS fails, We could check if RHS can be checked with b_check_boolean_expression
1057		Ai=Ao, get_binary_choice_wait_flag(not_equivalence,WF,WF2),
1058		b_enum_not_test_equivalence(LHS,RHS,LocalState,State,WF,WF2,Ai))).
1059		b_check_test_equivalence(PredRes,LHS,RHS,LocalState,State,WF,Aii,Ao) :-
1060		% print('checking <=> '), print_bexpr(LHS), print(' '), print(PredRes),nl,
1061	?	(var(PredRes),b_check_boolean_expression(RHS,LocalState,State,WF,PredRes2,Aii,Ao) % TO DO <---- REPLACE CUT
1062		-> /* also propagate from right to left */
1063	?	equiv_bidrectional_test_boolean_expression(PredRes,PredRes2,LHS,RHS,LocalState,State,WF)
1064		; Aii=Ao,
1065	?	equiv_test_boolean_expression(PredRes,pred_true,RHS,LocalState,State,WF,Aii)
1066		). % should we also add a binary choice flag ?? what about a=2 <=> b/=3 ??
1067
1068		:- block b_enum_test_equivalence(?,?,?,?,?,-,?).
1069		b_enum_test_equivalence(LHS,RHS,LocalState,State,WF,_WF2,Ai) :-
1070		b_test_boolean_expression(LHS,LocalState,State,WF,Ai,Aii), % TO DO: we could call b_test_inner_boolean_expression with Ai
1071		b_test_boolean_expression(RHS,LocalState,State,WF,Aii,_).
1072		b_enum_test_equivalence(LHS,RHS,LocalState,State,WF,_WF2,Ai) :-
1073		b_not_test_boolean_expression(LHS,LocalState,State,WF,Ai,Aii),
1074		b_not_test_boolean_expression(RHS,LocalState,State,WF,Aii,_).
1075
1076		%enumerate_bool(X,WF) :- !.
1077		enumerate_bool(X,Prio,WF) :- (nonvar(X) -> true /* already set */
1078		; get_wait_flag0(WF,WF0),
1079		enumerate_bool0(X,Prio,WF,WF0)).
1080
1081		:- block enumerate_bool0(?,?,?,-).
1082		enumerate_bool0(X,Prio,WF,_) :- (nonvar(X) -> true /* already set */
1083		; %print(enum_bool(X)), translate:print_bexpr(LHS),nl,
1084		% get_binary_choice_wait_flag(enumerate_bool,WF,WF2),
1085		get_wait_flag(Prio,enumerate_bool,WF,WF2), % what priority should we use ?? give time for other enumerators to decide the lhs of the disjunct; actions_cbtc is slower to setup with low priority
1086		enumerate_bool_aux(X,WF2)).
1087		:- block enumerate_bool_aux(-,-).
1088		%enumerate_bool_aux(P,WF) :- var(P),print(forcing_bool(P,WF)),nl,fail. %
1089		enumerate_bool_aux(pred_true,_).
1090		enumerate_bool_aux(pred_false,_).
1091
1092		:- block b_test_disjunction(?,?,?,?,?,-,?).
1093		b_test_disjunction(LHS,_RHS,LocalState,State,WF,_WF2,Ai) :-
1094	?	b_test_boolean_expression(LHS,LocalState,State,WF,Ai,_).
1095		b_test_disjunction(LHS,RHS,LocalState,State,WF,_WF2,Ai) :-
1096	?	b_not_test_boolean_expression(LHS,LocalState,State,WF,Ai,Aii),
1097	?	b_test_boolean_expression(RHS,LocalState,State,WF,Aii,_).
1098
1099		:- block b_not_test_conjunction(?,?,?,?,?,-,?).
1100		b_not_test_conjunction(LHS,_RHS,LocalState,State,WF,_WF2,Ai) :-
1101		b_not_test_boolean_expression(LHS,LocalState,State,WF,Ai,_).
1102		b_not_test_conjunction(LHS,RHS,LocalState,State,WF,_WF2,Ai) :-
1103	?	b_test_boolean_expression(LHS,LocalState,State,WF,Ai,Aii),
1104	?	b_not_test_boolean_expression(RHS,LocalState,State,WF,Aii,_).
1105
1106		:- block b_enum_not_test_equivalence(?,?,?,?,?,-,?).
1107		b_enum_not_test_equivalence(LHS,RHS,LocalState,State,WF,_WF2,Ai) :-
1108		b_test_boolean_expression(LHS,LocalState,State,WF,Ai,Aii), % we could call b_test_inner_boolean_expression with Ai
1109		b_not_test_boolean_expression(RHS,LocalState,State,WF,Aii,_).
1110		b_enum_not_test_equivalence(LHS,RHS,LocalState,State,WF,_WF2,Ai) :-
1111		b_not_test_boolean_expression(LHS,LocalState,State,WF,Ai,Aii),
1112		b_test_boolean_expression(RHS,LocalState,State,WF,Aii,_).
1113
1114
1115
1116		/* --------------------------------------*/
1117		/* b_not_test_boolean_expression */
1118		/* --------------------------------------*/
1119
1120		b_not_test_list_of_boolean_expression([],_,_,_WF).
1121		b_not_test_list_of_boolean_expression([B1|T],LS,S,WF) :-
1122		b_not_test_boolean_expression(B1,LS,S,WF),
1123		b_not_test_list_of_boolean_expression(T,LS,S,WF).
1124
1125		:- assert_pre(b_interpreter:b_not_test_boolean_expression_cs(E,LS,S,_,_),
1126		(bsyntaxtree:check_if_typed_predicate(E),type_check(LS,store),type_check(S,store))).
1127		:- assert_post(b_interpreter:b_not_test_boolean_expression_cs(_,_,_,_,_), true).
1128
1129
1130		% a version where we can provide an initial call stack entry for context
1131		b_not_test_boolean_expression_cs(E,LS,S,PredKind,Nr) :-
1132		init_wait_flags_cs(E,PredKind,Nr,b_not_test_boolean_expression_cs,WF), % TODO: we could register negation info
1133		% TO DO: call b_trace_test_components ?
1134	?	b_not_test_boolean_expression(E,LS,S,WF),
1135	?	ground_wait_flags(WF).
1136
1137		b_not_test_boolean_expression(E,LS,S,WF) :-
1138	?	empty_avl(Ai), b_not_test_boolean_expression(E,LS,S,WF,Ai,_).
1139
1140		:- assert_pre(b_interpreter:b_not_test_boolean_expression(E,LS,S,WF),
1141		(type_check(E,boolean_expression),type_check(LS,store),type_check(S,store), type_check(WF,wait_flag))).
1142		:- assert_post(b_interpreter:b_not_test_boolean_expression(_,_,_,_), true).
1143
1144		:- if(environ(prob_debug_watch_flag,true)).
1145		b_not_test_boolean_expression(b(Expr,_,Infos),LS,S,WF,Ai,Ao) :- !,
1146		(waitflag0_is_set(WF)
1147		-> debug:watch(400,b_interpreter:b_not_test_boolean_expression2(Expr,Infos,LS,S,WF,Ai,Ao))
1148		; debug:watch_det(400,b_interpreter:b_not_test_boolean_expression2(Expr,Infos,LS,S,WF,Ai,Ao)) ).
1149		:- else.
1150		b_not_test_boolean_expression(b(Expr,Type,Infos),LS,S,WF,Ai,Ao) :- !,
1151		(preference(smt_supported_interpreter,true)
1152		-> b_not_test_boolean_expression2(Expr,Infos,LS,S,WF,Ai,Ao),create_negation(b(Expr,Type,Infos),Neg),
1153		get_wait_flag1(smt_call,WF,BeforeEnumWF),
1154		gensym:gensym(smt_assertion_name,Symbol),
1155		smt_add_predicate(BeforeEnumWF,Neg,LS,S,Symbol)
1156	?	; b_not_test_boolean_expression2(Expr,Infos,LS,S,WF,Ai,Ao)).
1157		:- endif.
1158		b_not_test_boolean_expression(E,LS,S,WF,Ai,Ao) :-
1159		add_internal_error('Boolean (not) expression not properly wrapped: ',
1160		b_not_test_boolean_expression(E,LS,S,WF,Ai,Ao)),
1161		b_not_test_boolean_expression2(E,[],LS,S,WF,Ai,Ao).
1162
1163		b_not_test_boolean_expression2(truth,_,_,_,_WF,_Ai,_Ao) :- !,fail.
1164		b_not_test_boolean_expression2(falsity,_,_,_,_WF,Ai,Ao) :- !,Ai=Ao. % NOT COVERED (2)
1165		b_not_test_boolean_expression2(negation(BExpr),_,LocalState,State,WF,Ai,Ao) :- !,
1166		b_test_boolean_expression(BExpr,LocalState,State,WF,Ai,Ao).
1167		% following makes test 349 fail:
1168		%b_not_test_boolean_expression2(conjunct(LHS,RHS),Infos,LocalState,State,WF,Ai,Ao) :- !,
1169		% nl, print(' NOT: '),translate:print_bexpr(b(conjunct(LHS,RHS),pred,Infos)),nl,
1170		% create_negation(LHS,NegLHS), % TO DO: avoid this construction by generalising code for disjunct
1171		% create_negation(RHS,NegRHS),
1172		% b_test_boolean_expression2(disjunct(NegLHS,NegRHS),Infos,LocalState,State,WF,Ai,Ao).
1173		b_not_test_boolean_expression2(conjunct(LHS,RHS),Infos,LocalState,State,WF,Ai,Ao) :- !,
1174		b(conjunct(LHS,RHS),pred,Infos) = Conj,
1175		copy_wf_start(WF,not_conjunct,CWF),
1176	?	if(b_check_boolean_expression(Conj,LocalState,State,CWF,PredRes,Ai,Ao),
1177		(PredRes=pred_false,
1178	?	copy_wf_finish(WF,CWF)
1179		),
1180		if(b_check_boolean_expression(LHS,LocalState,State,CWF,LHSPredRes,Ai,Ao), % some redundant work with call above: TODO: avoid !
1181		(copy_wf_finish(WF,CWF),
1182		get_last_wait_flag(not_conjunct_rhs,WF,WF2), % before starting to enumerate infinite types: better try both possibilities:
1183		b_not_test_conjunction_rhs(LHSPredRes,RHS,LocalState,State,WF,Ai,WF2)
1184		),
1185		(Ai=Ao,
1186		get_priority_of_boolean_expression2(disjunct(LHS,RHS),StartPrio),
1187		%get_wait_flag(Prio,not_conjunct,WF,WF2),
1188		get_binary_choice_wait_flag_exp_backoff(StartPrio,not_conjunct,WF,WF2),
1189		% TO DO: we could check if LHS or RHS are registered in Ai as pred_true/pred_false ??
1190		b_not_test_conjunction(LHS,RHS,LocalState,State,WF,WF2,Ai))
1191		)
1192		).
1193
1194		b_not_test_boolean_expression2(implication(LHS,RHS),_,LocalState,State,WF,Ai,Ao) :- !,
1195		b_test_boolean_expression(LHS,LocalState,State,WF,Ai,Aii),
1196	?	b_not_test_boolean_expression(RHS,LocalState,State,WF,Aii,Ao).
1197		b_not_test_boolean_expression2(equivalence(LHS,RHS),_,LocalState,State,WF,Ai,Ao) :- !,
1198		b_not_test_equivalence(LHS,RHS,LocalState,State,WF,Ai,Ao).
1199		b_not_test_boolean_expression2(disjunct(LHS,RHS),_,LocalState,State,WF,Ai,Ao) :- !,
1200		b_not_test_boolean_expression(LHS,LocalState,State,WF,Ai,Aii),
1201		b_not_test_boolean_expression(RHS,LocalState,State,WF,Aii,Ao).
1202		b_not_test_boolean_expression2(lazy_let_pred(Id,AssignmentExpr,Expr),_I,LocalState,State,WF,Ai,Ao) :- !,
1203		add_lazy_let_id_and_expression(Id,AssignmentExpr,LocalState,State,NewLocalState,WF,Ai),
1204		b_not_test_boolean_expression(Expr,NewLocalState,State,WF,Ai,Ao). % we could use Ai,Ao version as lazy lets never interfere with each other and never invalidate existing expressions
1205		b_not_test_boolean_expression2(lazy_lookup_pred(Id),_Info,LocalState,_State,WF,Ai,Ao) :- !, Ai=Ao,
1206		lookup_value_for_existing_id_wf(Id,LocalState,(Trigger,Value),WF), % should normally only occur in LocalState; value introduced by lazy_let
1207		(Trigger,Value) = (pred_true,pred_false). % force evaluation
1208		b_not_test_boolean_expression2(value(PredVal),_Info,_LocalState,_State,_WF,Ai,Ao) :- !, % this can occur when lazy_lookup_pred gets compiled by b_compiler
1209		is_pred_false(PredVal),Ai=Ao.
1210		b_not_test_boolean_expression2(Expr,Info,LocalState,State,WF,Ai,Ao) :-
1211		% TO DO: we could put some of the operators into the Ai store (comparison operators)
1212	?	b_not_test_atomic_boolean_expression2(Expr,Info,LocalState,State,WF,Ai,Ao).
1213
1214		% Other boolean expressions, not involving boolean connectives
1215		b_not_test_atomic_boolean_expression2(exists(Parameters,RHS),Infos,LocalState,State,WF,Ai,Ao) :- !,
1216		/* #ID.(RHS) */
1217		Ai=Ao,
1218	?	b_not_test_exists(Parameters,RHS,Infos,LocalState,State,compile,WF).
1219		b_not_test_atomic_boolean_expression2(forall(Parameters,LHS,RHS),Infos,LocalState,State,WF,Ai,Ao) :- !,
1220		/* !ID.(LHS => RHS) */
1221		Ai=Ao,
1222		safe_create_texpr(negation(RHS),pred,Negation),
1223		conjunct_predicates_with_pos_info(LHS,Negation,Condition),
1224		% conjunct_predicates merges the used_ids Info in Condition
1225	?	b_test_exists(Parameters,Condition,Infos,LocalState,State,WF).
1226		/* TODO(DP, 2.8.2008): Extension for Z: a let-statement as predicate */
1227		b_not_test_atomic_boolean_expression2(let_predicate(Ids,AssignmentExprs,Pred),Infos,LocalState,State,WF,Ai,Ao) :-
1228		!,Ai=Ao, % any expression inside the LET cannot be safely reused
1229	?	set_up_localstate_for_let(Ids,ParaValues,AssignmentExprs,LocalState,State,LetState,WF),
1230		opt_push_wait_flag_call_stack_quantifier_info(WF,let_quantifier,Ids,ParaValues,Infos,WF2),
1231	?	b_not_test_boolean_expression(Pred,LetState,State,WF2). % NOT COVERED (10)
1232		/* TODO(DP, 2.8.2008): */
1233		b_not_test_atomic_boolean_expression2(freetype_case(Freetype,Case,Expr),_,LocalState,State,WF,Ai,Ao) :-
1234		!,Ai=Ao,b_compute_expression(Expr,LocalState,State,freeval(Freetype,RealCase,_),WF),
1235		dif(RealCase,Case). % NOT COVERED (11)
1236		b_not_test_atomic_boolean_expression2(finite(SetExpr),_,LocalState,State,WF,Ai,Ao) :-
1237		!, Ai=Ao,b_compute_expression(SetExpr,LocalState,State,Value,WF),
1238		kernel_call_predicate(is_infinite_set_wf(Value,WF),kernel_objects,WF,finite(SetExpr)).
1239		/* Extension for Kodkod */
1240		b_not_test_atomic_boolean_expression2(kodkod(ProblemId,_),_,LocalState,State,WF,Ai,Ao) :-
1241		!,Ai=Ao,get_wait_flag1(kodkod_negative_call,WF,WF0),
1242		kodkod_request(ProblemId,neg,LocalState,State,WF0). % NOT COVERED (12)
1243		b_not_test_atomic_boolean_expression2(partition(LHS,RHS),Info,LocalState,State,WF,Ai,Ao) :- !,
1244		b_interpreter_check:register_predicate(partition(LHS,RHS),Info,pred_false,Reused,Ai,Ao),
1245		(Reused==true -> true
1246		; b_compute_expression(LHS,LocalState,State,SV1,WF),
1247		l_compute_expression(RHS,LocalState,State,SV2,WF), % RHS is Prolog list of expressions
1248		kernel_call_predicate(not_partition_wf(SV1,SV2,WF),kernel_objects,WF,partition(LHS,RHS))
1249		).
1250		b_not_test_atomic_boolean_expression2(external_pred_call(FunName,Args),Info,LocalState,State,WF,Ai,Ao) :-
1251		!, Ai=Ao,
1252		(do_not_evaluate_args(FunName) -> EvaluatedArgs=[]
1253		; b_compute_expressions(Args, LocalState,State, EvaluatedArgs, WF)),
1254		push_wait_flag_call_stack_info(WF,external_call(FunName,EvaluatedArgs,Info),WF2),
1255		call_external_predicate(FunName,Args,EvaluatedArgs,LocalState,State,pred_false,Info,WF2).
1256		b_not_test_atomic_boolean_expression2(Pred,Info,LocalState,State,WF,Ai,Ao) :-
1257		b_interpreter_check:register_predicate(Pred,Info,pred_false,Reused,Ai,Ao),
1258		(Reused==true
1259		-> %% print('REUSED (not): '), translate:print_bexpr(Pred),nl,
1260		true
1261	?	; b_not_test_atomic_boolean_expression3(Pred,Info,LocalState,State,WF)).
1262		b_not_test_atomic_boolean_expression3(Expression,Info,LocalState,State,WF) :-
1263		functor(Expression,BOP,2),
1264	?	kernel_mappings:negate_binary_boolean_operator(BOP,NBOP),
1265		arg(1,Expression,Arg1),arg(2,Expression,Arg2),!,
1266		NExpression =.. [NBOP,Arg1,Arg2],
1267	?	b_test_atomic_boolean_expression2(NExpression,Info,LocalState,State,WF).
1268		b_not_test_atomic_boolean_expression3(Expression,Info,LocalState,State,WF) :-
1269		functor(Expression,BOP,2),
1270		kernel_mappings:negate_binary_boolean_operator_swap(BOP,NBOP),
1271		arg(1,Expression,Arg1),arg(2,Expression,Arg2),!,
1272		NExpression =.. [NBOP,Arg2,Arg1],
1273		b_test_atomic_boolean_expression2(NExpression,Info,LocalState,State,WF).
1274		b_not_test_atomic_boolean_expression3(E,_,_,_,_WF) :-
1275		add_internal_error('Uncovered boolean expression (not): ',E),
1276		print_functor(E),nl,fail.
1277
1278
1279		% test RHS of not-conjunction depending on outcome of LHS
1280		:- block b_not_test_conjunction_rhs(-,?,?,?,?,?,-).
1281		b_not_test_conjunction_rhs(pred_false,_RHS,_LocalState,_State,_WF,_Ai,_LWF).
1282		b_not_test_conjunction_rhs(pred_true,RHS,LocalState,State,WF,Ai,_LWF) :-
1283	?	b_not_test_boolean_expression(RHS,LocalState,State,WF,Ai,_).
1284
1285		/* -----------------------------*/
1286		/* b_compute_expression */
1287		/* -----------------------------*/
1288
1289
1290
1291		:- assert_must_succeed((b_interpreter:b_compute_expression(b(pow_subset(
1292		b(identifier(nm),set(integer),[])),set(set(integer)),[]),
1293		[], [bind(nm,[])],R,_WF),
1294		nonvar(R), custom_explicit_sets:expand_custom_set_to_list(R,[[]]))).
1295		:- assert_must_succeed((b_interpreter:b_compute_expression(b(pow_subset(
1296		b(identifier(nm),set(boolean),[])),set(set(boolean)),[]),[],
1297		[bind(nm,[pred_false /* bool_false */])],R,_WF),
1298		nonvar(R), custom_explicit_sets:expand_custom_set_to_list(R,ER),
1299		kernel_objects:equal_object(ER,[[pred_false /* bool_false */],[]]))).
1300
1301		:- assert_pre(b_interpreter:b_compute_expression(Exp,LS,State,_Val,WF),
1302		(nonvar(Exp),
1303		bsyntaxtree:check_if_typed_expression(Exp),
1304		type_check(LS,store),type_check(State,store), type_check(WF,wait_flag))).
1305		:- assert_post(b_interpreter:b_compute_expression(_E,_LS,_State,Val,WF),
1306		(b_interpreter:value_type(Val), type_check(WF,wait_flag))). %, nonvar(Val)
1307
1308		b_compute_expression_nowf(E,LS,S,R) :-
1309		b_compute_expression_nowf(E,LS,S,R,none,0).
1310
1311		b_compute_expression_nowf(E,LS,S,R,FormulaKind,Nr) :-
1312		get_texpr_info(E,Info),
1313	?	b_compute_expression_nowf(E,LS,S,R,FormulaKind,Nr,Info).
1314		b_compute_expression_nowf(E,LS,S,R,FormulaKind,Nr,Span) :-
1315	?	b_compute_expression_no_wf8(E,LS,S,R,FormulaKind,Nr,default,Span).
1316		% a variation where we tell ProB to expect non-symbolic / explicit values
1317		b_compute_explicit_epression_no_wf(E,LS,S,R,FormulaKind,Nr) :-
1318		get_texpr_info(E,Info),
1319	?	b_compute_explicit_epression_no_wf(E,LS,S,R,FormulaKind,Nr,Info).
1320		b_compute_explicit_epression_no_wf(E,LS,S,R,FormulaKind,Nr,Span) :-
1321	?	b_compute_expression_no_wf8(E,LS,S,R,FormulaKind,Nr,expect_explicit_value,Span).
1322		b_compute_expression_no_wf8(E,LS,S,R,FormulaKind,Nr,Expect,Span) :-
1323		%add_message(b_compute_expression,'Called Version wo WFLAGS: ', b_compute_expression(E,LS,S,R)),
1324		(Expect=expect_explicit_value -> WFInfos = [expect_explicit_value] ; WFInfos = []),
1325		(FormulaKind = none -> init_wait_flags(WF,WFInfos)
1326		; CallStackEntry = prob_command_context(eval_expr_command(FormulaKind,Nr),Span),
1327		init_wait_flags_and_push_call_stack(no_wf_available,CallStackEntry,WFInfos,WF)
1328		),
1329	?	b_compute_expression(E,LS,S,R,WF),
1330	?	ground_wait_flags(WF), % this will add abort errors and fail before enumerating the result:
1331		init_wait_flags(WF2,[b_compute_expression_nowf2]),
1332		get_texpr_type(E,Type),
1333		b_enumerate:b_tighter_enumerate_single_value(R,Type,Span,b_compute_expression_nowf,WF2), %should rarely be necessary
1334		% a non-ground result only occurs when WD error appears and in this case ground_wait_flags will fail after
1335		% adding the abort error (and thus no value is returned)
1336		% exceptions are test 1066 with a complicated set comprehension used in a function application
1337		% test 1861 relies on two phase enumeration
1338		ground_wait_flags(WF2).
1339
1340		l_compute_expression([],_LS,_S,[],_WF).
1341		l_compute_expression([H|T],LS,S,[CH|CT],WF) :-
1342		b_compute_expression(H,LS,S,CH,WF),
1343		l_compute_expression(T,LS,S,CT,WF).
1344
1345		:- if(environ(prob_debug_watch_flag,true)).
1346		b_compute_expressiond(b(Expr,Type,Info),LS,S,R,WF) :- !,
1347		((ground(Type), Type \== pred, Type \== subst) -> true
1348		; add_error_wf(b_compute_expression,'Expression has illegal type: ',b(Expr,Type,Info),WF)),
1349		check_value(R,b(Expr,Type,Info)),
1350		b_compute_expression2(Expr,Type,Info,LS,S,R,WF).
1351		:- block check_value(-,?).
1352		check_value(pred_true,_) :- !. check_value(pred_false,_) :- !.
1353		check_value(string(_),_) :- !.
1354		check_value([],_) :- !.
1355		check_value([H|T],E) :- !, check_value(H,E), check_value(T,E).
1356		check_value((A,B),E) :- !, check_value(A,E), check_value(B,E).
1357		check_value(fd(N,T),E) :- !, (nonvar(T) -> check_fd(N,T,E) ; check_err(fd(N,T),E)).
1358		check_value(global_set(GS),E) :- !,(nonvar(GS) -> true ; check_err(global_set(GS),E)).
1359		check_value(avl_set(AS),E) :- !,((nonvar(AS),AS=node(_,_,_,_,_)) -> true ; check_err(global_set(AS),E)).
1360		check_value(int(X),E) :- !,check_int(X,E).
1361		check_value(closure(P,T,B),E) :- !,
1362		(ground(P),ground(T),nonvar(B)
1363		-> (same_length(P,T) -> bsyntaxtree:check_ast(B) ; check_err(closure_not_same_length(P,T)))
1364		; check_err(closure(P,T,B),E)).
1365		check_value(rec(_),_) :- !. %TODO: check
1366		check_value(X,E) :- check_err(uncovered(X),E).
1367		% TO DO: add records + more thorough checking of global_set and closures and avl_sets
1368		:- block check_int(-,?).
1369		check_int(X,E) :- (number(X) -> true ; check_err(int(X),E)).
1370		:- block check_fd(-,?,?).
1371		check_fd(X,T,E) :- (number(X),b_get_fd_type_bounds(T,Low,Up),X>=Low,X=<Up -> true ; check_err(fd(X,T),E)).
1372
1373		check_err(V,E) :- add_internal_error('Illegal value when computing expression: ',V:E).
1374		b_compute_expression(E,LS,S,R,WF) :- !,
1375		(waitflag0_is_set(WF)
1376		-> debug:watch(100,b_interpreter:b_compute_expressiond(E,LS,S,R,WF))
1377		; debug:watch_det(100,b_interpreter:b_compute_expressiond(E,LS,S,R,WF))).
1378		:- else.
1379		b_compute_expression(b(Expr,Type,Info),LS,S,R,WF) :- !,
1380		((ground(Type), Type \== pred, Type \== subst) -> true
1381		; Type==pred -> add_internal_error_wf(b_interpreter,'Expected expression, not predicate: ',b(Expr,Type,Info),Info,WF)
1382		; Type==subst -> add_internal_error_wf(b_interpreter,'Expected expression, not substitution: ',b(Expr,Type,Info),Info,WF)
1383		; add_internal_error_wf(b_interpreter,'Expression has non-ground type: ',b(Expr,Type,Info),Info,WF)
1384		),
1385	?	b_compute_expression2(Expr,Type,Info,LS,S,R,WF).
1386		:- endif.
1387		b_compute_expression(Expr,LS,S,R,WF) :-
1388		add_internal_error('Expression not properly wrapped: ',b_compute_expression(Expr,LS,S,R,WF)),
1389		b_compute_expression2(Expr,unknown,[],LS,S,R,WF).
1390
1391
1392		:- use_module(bsyntaxtree,[get_texpr_set_type/2]).
1393
1394		%:- use_module(b_global_sets,[b_type2_set/2]).
1395		%b_compute_expression2(V,T,I,LS,S,R,_WF) :- nonvar(R), print('result_instantiated: '(R:V)),nl,fail.
1396	?	b_compute_expression2(value(Val),_T,_I,_LS,_S,V,WF) :- !, equal_object_wf(Val,V,WF). %Val=V.
1397		b_compute_expression2(boolean_true,_T,_I,_LState,_State,Res,_WF) :- !, Res = pred_true /* bool_true */. % for simple types we can use ordinary unification
1398		b_compute_expression2(boolean_false,_T,_I,_LState,_State,Res,_WF) :- !, Res = pred_false /* bool_false */.
1399		b_compute_expression2(integer_set(NSET),_T,_I,_LState,_State,Res,WF) :- !, equal_object_wf(Res,global_set(NSET),WF). %Res = global_set(NSET).
1400		b_compute_expression2(bool_set,_T,_I,_LState,_State,Res,WF) :- !, % b_type2_set(bool,Res).
1401		equal_object_wf(Res,avl_set(node(pred_false,true,1,empty,node(pred_true,true,0,empty,empty))),WF).
1402		% was equal_object(Res,[pred_true /* bool_true */,pred_false /* bool_false */]) % changing this to avl used to break test 800 Bosch Deadlock v9; probably because of identity closure detection instantiation
1403		b_compute_expression2(float_set,_T,_I,_LState,_State,Res,WF) :- !, equal_object_wf(Res,global_set('FLOAT'),WF).
1404		b_compute_expression2(real_set,_T,_I,_LState,_State,Res,WF) :- !, equal_object_wf(Res,global_set('REAL'),WF).
1405		b_compute_expression2(string_set,_T,_I,_LState,_State,Res,WF) :- !, equal_object_wf(Res,global_set('STRING'),WF).
1406		% was all_strings(Res). %% NOT COVERED (6)
1407		b_compute_expression2(string(S),_T,_I,_LState,_State,Res,_WF) :- !,
1408		% TODO(ML,26.8.2008): Check if we should use a different functor for syntax tree vs data
1409		Res = string(S).
1410		b_compute_expression2(typeset,Type,_I,_LState,_State,Res,WF) :- !,
1411		is_set_type(Type,ElType), % we could generate global_set('STRING'),... for certain types
1412		equal_object_wf(Res,closure('_zzzz_unary',[ElType],b(truth,pred,[])),WF).
1413		b_compute_expression2(empty_set,_T,_I,_LState,_State,Res,_WF) :- !, empty_set(Res).
1414		b_compute_expression2(empty_sequence,_T,_I,_LState,_State,Res,_WF) :- !, empty_sequence(Res).
1415		b_compute_expression2(event_b_identity,EType,_I,_LState,_State,Res,WF) :-
1416		get_set_type(EType,couple(Type,Type)),!,
1417		event_b_identity_for_type(Type,Res,WF).
1418		b_compute_expression2(integer(Val),_T,_I,_LocalState,_State,Res,_WF) :- !, Res = int(Val).
1419		b_compute_expression2(max_int,_T,_I,_LS,_S,Res,_WF) :-
1420		preferences:get_preference(maxint,CVal),!, Res = int(CVal).
1421		b_compute_expression2(min_int,_T,_I,_LS,_S,Res,_WF) :-
1422		preferences:get_preference(minint,CVal),!, Res = int(CVal).
1423		b_compute_expression2(identifier(Id),Type,Info,LocalState,State,Res,WF) :- !,
1424		lookup_value_in_store_and_global_sets_wf(Id,Type,LocalState,State,Value,Info,WF),
1425		equal_object_wf(Res,Value,WF).
1426		b_compute_expression2(lazy_lookup_expr(Id),_Type,_Info,LocalState,_State,Res,WF) :- !,
1427		lookup_value_for_existing_id_wf(Id,LocalState,(Trigger,Value),WF), % should normally only occur in LocalState; value introduced by lazy_let
1428		Trigger = pred_true, % force evaluation
1429		equal_object_wf(Res,Value,WF).
1430		b_compute_expression2(lazy_let_expr(Id,AssignmentExpr,Expr),_T,_I,LocalState,State,Value,WF) :-
1431		!,
1432		add_lazy_let_id_and_expression(Id,AssignmentExpr,LocalState,State,NewLocalState,WF),
1433		%Trigger = pred_true, % expressions cannot be delayed !? (TO DO: more refined check)
1434		%block_lazy_compute_expression(Trigger,_,AssignmentExpr,LocalState,State,IdValue,WF,Ai),
1435		b_compute_expression(Expr,NewLocalState,State,Value,WF).
1436		b_compute_expression2(real(Atom),_T,_I,_LocalState,_State,Res,_WF) :- !, construct_real(Atom,Res).
1437		b_compute_expression2(rec(Fields),_T,_I,LocalState,State,Record,WF) :- !,
1438	?	l_compute_field(Fields,LocalState,State,FieldValues,WF),
1439	?	construct_record_wf(FieldValues,Record,WF).
1440		b_compute_expression2(record_field(RecEx,Name),_T,_I,LocalState,State,Value,WF) :- !,
1441	?	b_compute_expression(RecEx,LocalState,State,RecValue,WF),
1442		access_record_wf(RecValue,Name,Value,WF).
1443		b_compute_expression2(freetype_set(Id),_T,_I,_LState,_State,Val,_WF) :- !, Val=freetype(Id). %% NOT COVERED (17)
1444		b_compute_expression2(function(Function,FunArg),Type,Info,LocalState,State,Res,WF) :- !,
1445	?	b_compute_expression_function(Function,FunArg,Type,Info,LocalState,State,Res,WF).
1446		b_compute_expression2(card(b(Arg1,Type,Info)),integer,OuterInfo,LocalState,State,Card,WF) :- !,
1447	?	b_compute_card(Arg1,Type,Info,OuterInfo,LocalState,State,Card,WF).
1448		b_compute_expression2(max(b(Arg1,Type,Info)),integer,_I,LocalState,State,Max,WF) :- !,
1449		b_compute_max(Arg1,Type,Info,LocalState,State,Max,WF).
1450		b_compute_expression2(min(b(Arg1,Type,Info)),integer,_I,LocalState,State,Min,WF) :- !,
1451		b_compute_min(Arg1,Type,Info,LocalState,State,Min,WF).
1452		b_compute_expression2(set_extension(Ex),Type,_I,LocalState,State,Res,WF) :- !,
1453	?	b_compute_expressions(Ex,LocalState,State,ExValue,WF),
1454		kernel_call(b_interpreter:convert_list_of_expressions_into_set_wf(ExValue,ValueSet,Type,WF),ExValue,WF, set_extension(Ex)),
1455	?	equal_object_wf(Res,ValueSet,WF).
1456		%kernel_call_convert_list_of_expressions_into_set_wf(ExValue,ValueSet,Type, WF).
1457		%b_compute_expression('ListTermes'(ListOfEx),LocalState,State,ValueSet,WF) :- !,
1458		% /* convert list of expressions of CASE statement into set of elements */
1459		% b_compute_expression(ListOfEx,LocalState,State,Value,WF),
1460		% init_wait_flags(WF),convert_list_of_expressions_into_set_wf(Value,ValueSet,set(any),WF),ground_wait_flags(WF).
1461		b_compute_expression2(sequence_extension(Ex),_T,_I,LocalState,State,ValueSeq,WF) :- !,
1462	?	b_compute_expressions(Ex,LocalState,State,Value,WF),
1463		kernel_call(b_interpreter:convert_list_of_expressions_into_sequence(Value,ValueSeq),Value,WF,sequence_extension(Ex)).
1464		b_compute_expression2(convert_bool(PRED),_T,_I,LocalState,State,Val,WF) :- !, /* B bool(.) operator */
1465	?	b_convert_bool(PRED,LocalState,State,WF,Val).
1466		b_compute_expression2(couple(El1,El2),_T,_I,LocalState,State,Result,WF) :- !, Result = (Val1,Val2),
1467	?	b_compute_expression(El1,LocalState,State,Val1,WF),
1468	?	b_compute_expression(El2,LocalState,State,Val2,WF).
1469		b_compute_expression2(comprehension_set(Parameters,Condition),_T,Info,LocalState,State,Result,WF) :- !,
1470	?	b_compute_comprehension_set(Parameters,Condition,Info,LocalState,State,Result,WF).
1471		b_compute_expression2(recursive_let(TId,TSet),OrigType,OrigInfo,LocalState,State,Result,WF) :- !,
1472		% LET TId = TSet in TSet
1473		( get_texpr_expr(TSet,comprehension_set(Parameters,Condition)) ->
1474		true % if the argument TSet is a comprehension set,
1475		% we just add a recursive parameter
1476		; get_texpr_set_type(TSet,Type) ->
1477		% if not, we construct a new comprehension set {x | x:TSet}
1478		unique_typed_id("_tmparg_",Type,TArg),
1479		Parameters=[TArg],
1480		safe_create_texpr(member(TArg,TSet),pred,Condition)
1481		;
1482		add_internal_error('Expected set as argument to recursive_let',
1483		b_compute_expression2(recursive_let(TId,TSet),OrigType,OrigInfo,LocalState,State,Result,WF)),fail
1484		),
1485		% Generate closure where the references to the recursion are kept
1486		% add recursion ID to parameters to prevent removal of references during compilation
1487		generate_recursive_closure(TId,recursion,[TId|Parameters],Condition,LocalState,State,Closure1,WF),
1488		% add_message(b_interpreter,'Recursive Let for: ',TId,TId),
1489		% remove recursion ID from parameters after compilation
1490		Closure1=closure([_|P],[_|T],Cond),RClosure=closure(P,T,Cond),
1491		% Generate closure where the references to the recursion are kept
1492		generate_recursive_closure(TId,RClosure,Parameters,Condition,LocalState,State,Result,WF).
1493		b_compute_expression2(general_sum(Ids,Condition,Expression),Type,Info,LocalState,State,SumResult,WF) :- !,
1494		b_general_sum_or_mul(Ids,Condition,Expression,Type,Info,LocalState,State,SumResult,WF,sum).
1495		b_compute_expression2(general_product(Ids,Condition,Expression),Type,Info,LocalState,State,MulResult,WF) :- !,
1496		b_general_sum_or_mul(Ids,Condition,Expression,Type,Info,LocalState,State,MulResult,WF,mul).
1497		/* Begin: Extensions for Z */
1498		b_compute_expression2(if_then_else(If,Then,Else),T,_I,LocalState,State,Value,WF) :- !,
1499		opt_push_wait_flag_call_stack_info(WF,b_expr_call(if_test,If),WF2),
1500	?	b_try_check_boolean_expression_wf(If,LocalState,State,WF2,PredRes),
1501		(var(PredRes), can_get_full_fd_value(T), preferences:preference(use_clpfd_solver,true),
1502		always_well_defined(Then), always_well_defined(Else)
1503		% Note: always_well_defined_or_disprover_mode probably not ok, as we evaluate the expressions unconditionally
1504		-> b_clpfd_if_then_else(PredRes,T,Then,Else,LocalState,State,Value,WF)
1505	?	; b_compute_if_then_else(PredRes,Then,Else,LocalState,State,Value,WF)
1506		).
1507		b_compute_expression2(let_expression_global(Ids,AssignmentExprs,Expr),_T,Info,LocalState,State,Value,WF) :-
1508		debug_println(4,global_let(Ids,Info)),
1509		% store variables globally (not in LocalState) to be visible to subsidiary operation_calls
1510		!, set_up_localstate_for_global_let(Ids,AssignmentExprs,LocalState,State,LetState,WF),
1511		b_compute_expression(Expr,LocalState,LetState,Value,WF).
1512		b_compute_expression2(let_expression(Ids,AssignmentExprs,Expr),_T,_I,LocalState,State,Value,WF) :-
1513	?	!, set_up_localstate_for_let(Ids,_ParaValues,AssignmentExprs,LocalState,State,LetState,WF),
1514	?	b_compute_expression(Expr,LetState,State,Value,WF). %% NOT COVERED (30)
1515		b_compute_expression2(freetype_constructor(Id,Case,Expr),_T,_I,LocalState,State,FreeValue,WF) :-
1516		!, FreeValue = freeval(Id,Case,Value),
1517		b_compute_expression(Expr,LocalState,State,Value,WF). %% NOT COVERED (32)
1518		b_compute_expression2(freetype_destructor(Id,Case,Expr),_T,Info,LocalState,State,Value,WF) :-
1519		!, b_compute_expression(Expr,LocalState,State,freeval(Id,VCase,VValue),WF),
1520		check_freetype_case(Id,Case,VCase,VValue,Value,Info,WF).
1521		/* End: Extensions for Z */
1522		b_compute_expression2(assertion_expression(Cond,ErrMsg,Expr),T,Info,LocalState,State,Value,WF) :- !,
1523		opt_push_wait_flag_call_stack_info(WF,
1524		span_predicate(b(assertion_expression(Cond,ErrMsg,b(value(string('')),string,[])),T,Info),LocalState,State),WF2),
1525		% should we use another term for call stack?
1526		(get_preference(disprover_mode,true) -> PredRes = pred_true ; true), % in Disprover mode we know Cond must be true
1527	?	b_try_check_boolean_expression_no_enum_wf(Cond,LocalState,State,WF2,PredRes), % DO NOT ENUM, unless we cannot reify
1528		% does not make sense to enumerate PredRes as with pred_false we get no value anyway
1529		% however, we may get pending co-routines if Cond cannot be reified
1530		( PredRes==pred_false ->
1531		translate_bexpression_with_limit(Cond,100,CS),
1532		add_wd_error_span(ErrMsg,CS,span_predicate(Cond,LocalState,State),WF2),
1533		get_last_wait_flag(assertion_expression,WF2,WFC),
1534		when(nonvar(WFC),
1535		(ground_value(Value) -> true % we have a WD Error, any Value goes
1536		; b_compute_expression(Expr,LocalState,State,Value,WF2) % compute Value; avoid infinite enumeration of possible values; useful e.g. for prj1/prj2 assertion expressions
1537		))
1538	?	; b_compute_expression(Expr,LocalState,State,Value,WF),
1539		add_wd_error_if_false(PredRes,ErrMsg,Cond,span_predicate(Cond,LocalState,State),WF2)
1540		). %% NOT COVERED (34)
1541		b_compute_expression2(multiplication(Arg1,Arg2),integer,Info,LocalState,State,Value,WF) :-
1542		same_texpr(Arg1,Arg2), !, % is less useful when CLPFD is already turned on, calls square(Arg1,Value,WF)
1543		b_compute_expression(Arg1,LocalState,State,SV1,WF),
1544		unary_kernel_call(kernel_objects,square,SV1,Value,WF,multiplication(Arg1,Arg1),integer,Info).
1545		b_compute_expression2(image(Relation,Set),_EType,_Info,LocalState,State,Value,WF) :-
1546		special_operator_for_image(Relation,Kind,Args),
1547		% we have closure1(Rel)[Set] or similar -> avoid computing full closure
1548		!,
1549	?	b_compute_expression(Set,LocalState,State,SV,WF),
1550		b_compute_expressions(Args,LocalState,State,EArgs,WF),
1551	?	kernel_call(bsets_clp:image_for_special_operator(Kind,EArgs,SV,Value,WF),[SV|EArgs],WF,image(Relation,Set)).
1552		b_compute_expression2(external_function_call(FunName,Args),EType,Info,LocalState,State,Value,WF) :-
1553		!,
1554	?	b_compute_expressions(Args, LocalState,State, EvaluatedArgs, WF),
1555		push_wait_flag_call_stack_info(WF,external_call(FunName,EvaluatedArgs,Info),WF2),
1556	?	call_external_function(FunName,Args,EvaluatedArgs,Value,EType,Info,WF2).
1557		b_compute_expression2(Expression,EType,Info,LocalState,State,Res,WF) :-
1558		is_set_type(EType,Type),
1559		/* avoid evaluating certain expensive expressions:
1560		convert them into symbolic closures and expand only if really required */
1561		functor(Expression,UnOp,1),
1562		symbolic_closure_unary_operator(UnOp),
1563		/* TO DO: UNFOLD THIS OR WRAP in CONSTRUCTOR */
1564		arg(1,Expression,BType),
1565		!, %preferences:get_preference(convert_types_into_closures,true),!,
1566		% print_message(delayed_un_op(UnOp,BType)),
1567	?	b_compute_expression(BType,LocalState,State,ArgValue,WF),
1568		( do_not_keep_symbolic_unary(UnOp,ArgValue),
1569		unary_function(UnOp,Module,KernelFunction) ->
1570		/* special treatment for empty set or other situations: no need to keep symbolic */
1571	?	unary_kernel_call(Module,KernelFunction,ArgValue,Res,WF,Expression,EType,Info)
1572		;
1573		get_texpr_type(BType,ArgType),
1574		create_texpr(value(ArgValue),ArgType,[],TValue),
1575		ClosureSetExpression =.. [UnOp,TValue],
1576		construct_member_closure('_zzzz_unary',Type,Info,ClosureSetExpression,Value),
1577	?	((unop_to_be_marked_as_symbolic(UnOp,ArgValue) ; member(prob_annotation('SYMBOLIC'),Info)) ->
1578		mark_closure_as_symbolic(Value,SValue),
1579		equal_object_wf(Res,SValue,WF)
1580		; equal_object_wf(Res,Value,WF))
1581
1582		).
1583		b_compute_expression2(Expression,EType,Info,LocalState,State,Res,WF) :-
1584		is_set_type(EType,Type),
1585		/* avoid evaluating certain expensive expressions:
1586		convert them into symbolic closures and expand only if really required */
1587		functor(Expression,BinOp,2),
1588		arg(1,Expression,BType1),
1589		arg(2,Expression,BType2),
1590		kernel_mappings:symbolic_closure_binary_operator(BinOp),
1591		!,
1592		%preferences:get_preference(convert_types_into_closures,true),!,
1593	?	b_compute_expression(BType1,LocalState,State,ArgValue1,WF),
1594		(binary_arg1_determines_value(BinOp,ArgValue1,DetResult)
1595		-> /* print(det(BinOp,ArgValue1)),nl, */
1596		equal_object_wf(Res,DetResult,b_compute_expression2(BinOp),WF)
1597		; b_compute_expression(BType2,LocalState,State,ArgValue2,WF),
1598		% print_message(delayed_bin_op(BinOp,ArgValue1,ArgValue2)),
1599		(is_definitely_empty(BinOp,ArgValue1,ArgValue2)
1600		-> empty_set(Res)
1601		; if(do_not_keep_symbolic(BinOp,ArgValue1,ArgValue2,ERes,WF),
1602		% then:
1603		equal_object_wf(Res,ERes,b_compute_expression2(BinOp),WF),
1604		% else:
1605		(get_texpr_type(BType1,TypeArg1), create_texpr(value(ArgValue1),TypeArg1,[],TArg1),
1606		get_texpr_type(BType2,TypeArg2), create_texpr(value(ArgValue2),TypeArg2,[],TArg2),
1607		ClosureSetExpression =.. [BinOp,TArg1,TArg2],
1608		construct_member_closure('_zzzz_unary',Type,Info,ClosureSetExpression,Value),
1609		% print('Constructed Symbolic Closure : '), translate:print_bvalue(Value),nl,
1610	?	(binop_to_be_marked_as_symbolic(BinOp,ArgValue1,ArgValue2) ->
1611		mark_closure_as_symbolic(Value,SValue),
1612		equal_object_wf(Res,SValue,WF)
1613		; equal_object_wf(Res,Value,WF))
1614		)
1615		) % if
1616		)
1617		).
1618		b_compute_expression2(Expression,Type,Info,LocalState,State,Value,WF) :-
1619		functor(Expression,Op,1),
1620		unary_function(Op,Module,KernelFunction),
1621		arg(1,Expression,Arg1),!,
1622		%opt_push_wait_flag_call_stack_info(WF,b_operator_arg_evaluation(Op,1,[SV1],Arg1),WF1),
1623	?	b_compute_expression(Arg1,LocalState,State,SV1,WF),
1624	?	unary_kernel_call(Module,KernelFunction,SV1,Value,WF,Expression,Type,Info).
1625		b_compute_expression2(Expression,Type,Info,LocalState,State,Value,WF) :-
1626		functor(Expression,Op,2),
1627		binary_function(Op,Module,KernelFunction),
1628		arg(1,Expression,Arg1),
1629		arg(2,Expression,Arg2),!,
1630		%opt_push_wait_flag_call_stack_info(WF,b_operator_arg_evaluation(Op,1,[SV1,_],Arg1),WF1),
1631	?	b_compute_expression(Arg1,LocalState,State,SV1,WF),
1632		(binary_arg1_determines_value(Op,SV1,Result) % we could disable this if find_abort_values=true or if SV1 not guaranteed to be wd
1633		->
1634		equal_object_wf(Value,Result,b_compute_expression2(Op),WF)
1635	?	; b_compute_expression(Arg2,LocalState,State,SV2,WF),
1636	?	binary_kernel_call(Module,KernelFunction,SV1,SV2,Value,WF,Expression,Type,Info)
1637		).
1638		b_compute_expression2(operation_call_in_expr(Operation,Parameters),_T,Info,LocalState,State,Value,WF) :-
1639		!, def_get_texpr_id(Operation,op(OperationName)),
1640		% TODO: check that this is a query operation; probably done in type checker
1641		b_execute_operation_in_expression(OperationName,LocalState,State,Parameters,Value,Info,WF).
1642		b_compute_expression2(E,T,Info,_L,_S,_R,_WF) :-
1643		(T==pred -> add_internal_error('Uncovered expression; looks like a predicate in the wrong place: ',b(E,T,Info))
1644		; T==subst -> add_internal_error('Uncovered expression; looks like a substitution in the wrong place: ',b(E,T,Info))
1645		; add_internal_error('Uncovered expression: ',b(E,T,Info))
1646		),
1647		print_functor(E), print(' : '), print(T),nl,fail.
1648
1649		make_couplise([A],R) :- !,R=A.
1650		make_couplise([A,B],R) :- !,R=(A,B).
1651		make_couplise([A,B|Rest],Result) :- !,
1652		make_couplise([(A,B)|Rest],Result).
1653		make_couplise(A,_) :- add_internal_error('Illegal operation call result:',A),fail.
1654
1655		% ---
1656
1657
1658		% check if a symbolic_closure_unary_operator result should be marked with prob_annotation(SYMBOLIC)
1659		% because direct sub-args are marked SYMBOLIC
1660		unop_to_be_marked_as_symbolic(UnOp,Value) :- nonvar(Value),
1661	?	to_be_marked_as_symbolic_aux(UnOp,Value).
1662		to_be_marked_as_symbolic_aux(struct,rec(Fields)) :- !,
1663	?	member(field(_,SymbolicClosure),Fields),
1664	?	is_symbolic_closure(SymbolicClosure).
1665		%to_be_marked_as_symbolic_aux(pow_subset,SymbolicClosure) :- is_symbolic_closure(SymbolicClosure).
1666		%to_be_marked_as_symbolic_aux(pow1_subset,SymbolicClosure) :- is_symbolic_closure(SymbolicClosure).
1667	?	to_be_marked_as_symbolic_aux(_,SymbolicClosure) :- is_symbolic_closure(SymbolicClosure).
1668
1669		% check if a symbolic_closure_binary_operator result should be marked with prob_annotation(SYMBOLIC)
1670		% because direct sub-args are marked SYMBOLIC
1671		binop_to_be_marked_as_symbolic(interval,_,_) :- !, fail.
1672		%binop_to_be_marked_as_symbolic(overwrite,_,_) :- !, true. % TO DO: fix by detecting infinite <+ closures
1673	?	binop_to_be_marked_as_symbolic(set_subtraction,ArgVal1,_) :- !, is_symbolic_closure(ArgVal1).
1674		binop_to_be_marked_as_symbolic(intersection,ArgVal1,ArgVal2) :-
1675	?	(finite_reasonably_sized_set(ArgVal1) ; finite_reasonably_sized_set(ArgVal2)), !,
1676		fail. % intersection is finite and reasonably sized
1677	?	binop_to_be_marked_as_symbolic(_,ArgVal1,_) :- is_symbolic_closure(ArgVal1).
1678	?	binop_to_be_marked_as_symbolic(_,_,ArgVal2) :- is_symbolic_closure(ArgVal2).
1679		% ---
1680
1681		% check if we have a finite known set that can be reasonably represented
1682		% see small_known_set/1 is kernel_mappings
1683		finite_reasonably_sized_set(AVL) :- nonvar(AVL), AVL=avl_set(_). % already expanded; so it can be represented in memory
1684		finite_reasonably_sized_set(Closure) :- nonvar(Closure),
1685		custom_explicit_sets:is_interval_closure(Closure,From,To), integer(From), integer(To),
1686		1+To-From < 250000. % what value should we use here?
1687
1688		lazy_compute_expression(TRIGGER,AssignmentExpr,LocalState,State,IdValue,WF,Ai) :-
1689		get_enumeration_finished_wait_flag(WF,F),
1690		block_lazy_compute_expression(TRIGGER,F,AssignmentExpr,LocalState,State,IdValue,WF,Ai).
1691
1692		:- block block_lazy_compute_expression(-,-,?,?,?, ?,?,?).
1693		block_lazy_compute_expression(TRIGGER,_F,_AssignmentExpr,_LocalState,_State,_IdValue,_WF,_Ai) :-
1694		var(TRIGGER),!.
1695		block_lazy_compute_expression(pred_true,_,AssignmentExpr,LocalState,State,IdValue,WF,Ai) :-
1696		AssignmentExpr = b(Expr,Type,Infos),
1697		(Type \== pred -> b_compute_expression2(Expr,Type,Infos,LocalState,State,IdValue,WF)
1698		; IdValue == pred_true -> b_test_boolean_expression2(Expr,Infos,LocalState,State,WF,Ai,_)
1699		; IdValue == pred_false -> b_not_test_boolean_expression2(Expr,Infos,LocalState,State,WF,Ai,_)
1700		; b_check_boolean_expression(AssignmentExpr,LocalState,State,WF,PredVal,Ai,_) -> IdValue = PredVal
1701		; % reification of check_boolean_expression failed:
1702		b_try_check_failed(AssignmentExpr,LocalState,State,'$ENUMERATION',WF,IdValue,'$GENERATE_ON_DEMAND')
1703		).
1704		block_lazy_compute_expression(pred_false,_,_AssignmentExpr,_LocalState,_State,[],_WF,_Ai). % maybe generate any value ??
1705
1706		% ---
1707
1708		:- block add_wd_error_if_false(-,?,?,?,?).
1709		add_wd_error_if_false(pred_true,_,_,_,_).
1710		add_wd_error_if_false(pred_false,ErrMsg,Cond,Span,WF) :-
1711		translate_bexpression_with_limit(Cond,100,CS),
1712		%(Span=span_predicate(P,LS,State) -> tcltk_interface:write_dot_file_for_pred_expr_and_state(P, LS, State,'/tmp/prob_wd_error.dot') ; true),
1713		add_wd_error_span(ErrMsg,CS,Span,WF).
1714
1715		% ---
1716
1717
1718		:- use_module(kernel_tools,[ground_value/1]).
1719		% compute function application:
1720		b_compute_expression_function(Function,FunArg,Type,Info,LocalState,State,Res,WF) :-
1721		preferences:preference(find_abort_values,false), % the treatment below will not check, e.g., if the set extension is really a function
1722		is_extension_function(Function,FInfo,ExFun), !,
1723		/* a set extension applied to an argument: in some cases we can can first evaluate the argument,
1724		and then avoid having to compute the set_extension for all non-matching args */
1725		b_compute_expression(FunArg,LocalState,State,ArgValue,WF),
1726		% TO DO : should we only do this if ArgValue is known ?? otherwise the standard treatment is better ??
1727		% Note: b_compiler has a special rule to not remove this optimisation
1728		Span = span_predicate(b(function(Function,FunArg),Type,Info),LocalState,State),
1729		opt_push_wait_flag_call_stack_info(WF,function_call(Function,ArgValue,Info),WF2), % small performance hit; hence we only push onto call_stack in TRACE_INFO mode
1730		((memberchk(contains_wd_condition,FInfo) ; % relevant for test 1302; but machine seems to contain real WD error
1731		preferences:preference(use_clpfd_solver,false) ;
1732		ground_value(ArgValue))
1733		-> b_apply_function_set_extension(ExFun,ArgValue,LocalState,State,Res,WF2,Span)
1734		; /* the standard treatment can infer information about the result,... in clpfd_mode */
1735		b_compute_expression(Function,LocalState,State,FValue,WF),
1736		get_texpr_type(Function,FunctionType),
1737		kernel_call_apply_to(FValue,ArgValue,Res,FunctionType,Span,WF2)).
1738		%b_compute_expression_function(b(comprehension_set(Parameters,Condition),_,SInfo),Arg,Type,Info,LocalState,State,Value,WF) :- !,
1739		% b_compute_comprehension_set_symbolic(Parameters,Condition,SInfo,LocalState,State,FValue,WF),
1740		% b_compute_expression(Arg,LocalState,State,ArgValue,WF),
1741		% Span = span_predicate(b(function(Function,Arg),Type,Info),LocalState,State),
1742		% get_texpr_type(Function,FunctionType),
1743		% kernel_call_apply_to(FValue,ArgValue,Value,FunctionType,Span,WF).
1744		b_compute_expression_function(Function,FunArg,_Type,Info,LocalState,State,Value,WF) :-
1745		special_operator_for_image(Function,Kind,Args),!, % detect e.g. iterate(rel,k)(x)
1746		b_compute_expression(FunArg,LocalState,State,SV,WF),
1747		b_compute_expressions(Args,LocalState,State,EArgs,WF),
1748		kernel_call(bsets_clp:apply_fun_for_special_operator(Kind,EArgs,SV,Value,WF,Info),
1749		[SV|EArgs],WF,function(Function,FunArg)).
1750		b_compute_expression_function(Function,Arg,Type,Info,LocalState,State,Value,WF) :-
1751		opt_push_wait_flag_call_stack_info(WF,function_call(Function,ArgValue,Info),WF2),
1752	?	b_compute_expression(Function,LocalState,State,FValue,WF2),
1753	?	b_compute_expression(Arg,LocalState,State,ArgValue,WF2),
1754		Span = span_predicate(b(function(Function,Arg),Type,Info),LocalState,State),
1755		get_texpr_type(Function,FunctionType),
1756		% TODO: do we still need the span predicate when we have the function_call call_stack infos?
1757	?	kernel_call_apply_to(FValue,ArgValue,Value,FunctionType,Span,WF2).
1758
1759
1760		:- use_module(bsyntaxtree,[get_set_type/2,is_set_type/2]).
1761		:- use_module(kernel_cardinality_attr,[finite_cardinality_as_int_with_type_wf/5]).
1762		b_compute_card(Arg1,Type,Info,OuterInfo,LocalState,State,Card,WF) :-
1763	?	b_compute_card2(Arg1,Type,Info,OuterInfo,LocalState,State,Card,WF),
1764		% maybe we should move this code below inside kernel_objects ??
1765		(ground(Card) -> true
1766		; get_set_type(Type,SetElType), % TO DO: only needed for cardinality_of_set_extension_list
1767	?	kernel_objects:max_cardinality(SetElType,MaxCard), % this could be precomputed statically
1768		(number(MaxCard) -> kernel_objects:in_nat_range(Card,int(0),int(MaxCard))
1769		; kernel_objects:greater_than_equal(Card,int(0)) % not sure this is required
1770		)
1771		).
1772		b_compute_card2(set_extension(Ex),_,_,_,LocalState,State,Card,WF) :- !,
1773		b_compute_expressions(Ex,LocalState,State,ExValue,WF),
1774		kernel_objects:cardinality_of_set_extension_list(ExValue,Card,WF).
1775		b_compute_card2(range(F),_,_,_,LocalState,State,Card,WF) :- !,
1776		b_compute_expression(F,LocalState,State,SV1,WF),
1777		kernel_objects:cardinality_of_range(SV1,Card,WF).
1778		b_compute_card2(comprehension_set(Parameters,Condition),Type,Info,OuterInfo,LocalState,State,Card,WF) :- !,
1779		get_set_type(Type,SetElType),
1780		% ensure that we keep the closure and don't expand it:
1781	?	b_compute_comprehension_set_symbolic(Parameters,Condition,Info,LocalState,State,SV1,WF),
1782	?	kernel_mappings:must_succ_kernel_call(
1783		kernel_cardinality_attr:finite_cardinality_as_int_with_type_wf(SV1,SetElType,OuterInfo,Card,WF),SV1,WF,card).
1784		% TO DO: treat comprehension set + things like card({x|x>1 & x<2**e & x mod 2 = 0}) = 0
1785		b_compute_card2(Arg1,Type,Info,OuterInfo,LocalState,State,Card,WF) :-
1786		get_set_type(Type,SetElType),
1787		b_compute_expression2(Arg1,Type,Info,LocalState,State,SV1,WF),
1788	?	kernel_mappings:must_succ_kernel_call(
1789		kernel_cardinality_attr:finite_cardinality_as_int_with_type_wf(SV1,SetElType,OuterInfo,Card,WF),SV1,WF,card).
1790
1791		b_compute_max(set_extension(Ex),_,Info,LocalState,State,Max,WF) :- !,
1792		b_compute_expressions(Ex,LocalState,State,ExValue,WF),
1793		kernel_objects:maximum_of_set_extension_list(ExValue,Max,Info,WF).
1794		b_compute_max(Arg1,Type,Info,LocalState,State,Max,WF) :-
1795		b_compute_expression2_symbolic(Arg1,Type,Info,LocalState,State,SV1,WF),
1796		kernel_mappings:must_succ_kernel_call(kernel_objects:maximum_of_set(SV1,Max,Info,WF),SV1,WF,max).
1797
1798		b_compute_min(set_extension(Ex),_,Info,LocalState,State,Min,WF) :- !,
1799		b_compute_expressions(Ex,LocalState,State,ExValue,WF),
1800		kernel_objects:minimum_of_set_extension_list(ExValue,Min,Info,WF).
1801		/* doesnot really buy a lot: */
1802		/*b_compute_min(union(Arg1,Arg2),_,Info,LocalState,State,Min,WF) :-
1803		Arg1 = b(set_extension(Ex),Type1,Info1),
1804		!,
1805		b_compute_min(set_extension(Ex),Type1,Info1,LocalState,State,Min1,WF),
1806		b_compute_expression(Arg2,LocalState,State,SV2,WF),
1807		b_compute_min2(SV2,Min1,Min,Info,WF).
1808		:- block b_compute_min2(-,?,?,?,?).
1809		b_compute_min2([],Min1,Res,_,_WF) :- !, Res=Min1.
1810		b_compute_min2(SV1,Min1,Res,Info,WF) :-
1811		kernel_mappings:must_succ_kernel_call(kernel_objects:minimum_of_set(SV1,Min2,Info,WF),SV1,WF,min),
1812		min(Min1,Min2,Res).
1813		min(int(A),int(B),int(Res)) :- kernel_objects:minimum(A,B,Res). */
1814		b_compute_min(Arg1,Type,Info,LocalState,State,Min,WF) :-
1815		b_compute_expression2_symbolic(Arg1,Type,Info,LocalState,State,SV1,WF),
1816		kernel_mappings:must_succ_kernel_call(kernel_objects:minimum_of_set(SV1,Min,Info,WF),SV1,WF,min).
1817
1818		generate_recursive_closure(TRecId,RecValue,Parameters,Condition,LocalState,State,Result,WF) :-
1819		get_texpr_id(TRecId,RecId),
1820		add_var_to_localstate(RecId,RecValue,LocalState,State1),
1821		debug_println(9,generating_recursive_closure(RecId,Parameters)),
1822		b_generate_rec_closure_aux(RecId,Parameters,Condition,State1,State,RClosure1,WF),
1823		mark_closure_as_recursive(RClosure1,RClosure2),
1824		mark_closure(RClosure2,[recursive(TRecId)],Result),
1825		( debug_mode(off) -> true
1826		; ground_value(Result) -> true
1827		; term_variables(Result,TV),
1828		add_message(b_interpreter,'non-ground closure generated: ',TV:Result,Condition)
1829		).
1830		% a variation of b_generate_closure
1831		b_generate_rec_closure_aux(RecId,Parameters,Condition,LocalState,State,Result,WF) :-
1832		split_names_and_types(Parameters,Names,Types),
1833		construct_closure(Names,Types,ClosurePred,Result),
1834		% now add RecId to parameters to prevent looking up recursive calls
1835		b_compiler:b_compile(Condition,[RecId|Names],LocalState,State,ClosurePred,WF).
1836
1837		% check if a freetype value has the expected case, if not
1838		% generate a WD-error
1839		check_freetype_case(Id,Case,VCase,Inner,Value,Info,WF) :-
1840		get_enumeration_finished_wait_flag(WF,F),
1841		check_freetype_case2(Id,Case,VCase,Inner,Value,Info,F,WF).
1842		:- block check_freetype_case2(?,?,-,?,?,?,-,?).
1843		check_freetype_case2(Id,Case,VCase,Inner,Value,Info,_F,WF) :-
1844		( nonvar(VCase) ->
1845		( Case=VCase -> equal_object_wf(Inner,Value,check_freetype_case2,WF)
1846		;
1847		ajoin(['cannot apply destructor for data type ',Id,
1848		', expected constructor ',Case,', but got: '],Msg),
1849		add_wd_error_set_result(Msg,VCase,Inner,Value,Info,WF))
1850		; % the computation has finished without value,
1851		true). % just drop the check
1852
1853		% check if we have a set_extension argument representing an explicit function
1854		% {a |-> f1, b |-> f2, ...} or [f1,f2]
1855		is_extension_function(b(A,_,Info),Info,C) :- is_extension_function_aux(A,C).
1856		is_extension_function_aux(set_extension(Ex),CaseList) :- is_set_extension_function(Ex,CaseList).
1857		is_extension_function_aux(sequence_extension(Ex),CaseList) :- is_sequence_extension_function(Ex,1,CaseList).
1858		is_set_extension_function([],[]).
1859		is_set_extension_function([b(Couple,TC,_)|T],[case(A,B)|ST]) :- is_couple(Couple,TC,A,B),
1860		is_set_extension_function(T,ST).
1861		is_sequence_extension_function([],_,[]).
1862		is_sequence_extension_function([B|T],Nr,[case(b(value(int(Nr)),integer,[]),B)|ST]) :- N1 is Nr+1,
1863		is_sequence_extension_function(T,N1,ST).
1864
1865		is_couple(couple(A,B),_,A,B).
1866		is_couple(value((VA,VB)),couple(TA,TB), b(value(VA),TA,[]), b(value(VB),TB,[])).
1867
1868		:- use_module(kernel_equality,[equality_objects_wf/4]).
1869		b_apply_function_set_extension([],FunArgVal,_LocalState,_State,_Res,WF,Span) :-
1870		add_wd_error_span('Function applied outside of domain (#8): ','@fun'(FunArgVal,[]),Span,WF).
1871		b_apply_function_set_extension([case(A,B)|T],FunArgVal,LocalState,State,Res,WF,Span) :-
1872		b_compute_expression(A,LocalState,State,AVal,WF),
1873		equality_objects_wf(AVal,FunArgVal,EqRes,WF),
1874		% TO DO: if Res is known, we can call equality_objects(BVal,Res,ResEqRes)
1875	?	b_apply_function_set_extension_aux(EqRes,B,T,FunArgVal,LocalState,State,Res,WF,Span).
1876
1877		:- block b_apply_function_set_extension_aux(-,?,?,?, ?,?,?,?,?).
1878		b_apply_function_set_extension_aux(pred_true,B,_T,_FunArgVal,LocalState,State,Res,WF,_Span) :-
1879		b_compute_expression(B,LocalState,State,BVal,WF), %print(value(BVal)),nl,
1880	?	equal_object_wf(BVal,Res,b_apply_function_set_extension_aux,WF).
1881		b_apply_function_set_extension_aux(pred_false,_B,T,FunArgVal,LocalState,State,Res,WF,Span) :-
1882	?	b_apply_function_set_extension(T,FunArgVal,LocalState,State,Res,WF,Span).
1883
1884
1885		% --------------------- SIGMA & PI ------------------------
1886		:- use_module(bsyntaxtree,[is_membership_or_equality/3,same_id/3]).
1887		/* first clause: try to do a specific treatment for formulas of the form SIGMA(ID).(ID:SET|EXPR) */
1888		/* Advantage: will not delay as long before computing comprehension_set SET ; see test 1312 */
1889		b_general_sum_or_mul([TID],Condition,Expression,Type,_Info,LocalState,State,SumResult,WF,SUMorMUL) :-
1890		is_membership_or_equality(Condition,MID,SET),
1891		same_id(TID,MID,_),!,
1892		b_compute_expression(SET,LocalState,State,SETResult,WF),
1893		b_general_sum_or_mul_over_set([TID],SETResult,Expression,Type,LocalState,State,SumResult,WF,SUMorMUL).
1894		b_general_sum_or_mul(Ids,Condition,Expression,Type,Info,LocalState,State,SumMulResult,WF,SUMorMUL) :-
1895		b_compute_comprehension_set(Ids,Condition,Info,LocalState,State,SETResult,WF),
1896		(var(SETResult) -> perfmessagecall(sigma_pi_not_expanded_or_reified(SUMorMUL),
1897		translate:print_bexpr(Condition),Condition) ; true),
1898		b_general_sum_or_mul_over_set(Ids,SETResult,Expression,Type,LocalState,State,SumMulResult,WF,SUMorMUL).
1899
1900
1901		:- block b_general_sum_or_mul_over_set(?,-, ?,?,?,?, ?,?,?).
1902		b_general_sum_or_mul_over_set([TID],SETResult,Expression,Type,_LS,_S,SumResult,WF,SUMorMUL) :-
1903		Type=integer, % TO DO: also for real
1904		get_texpr_id(Expression,ID), % check if we just sum the elements of the list SIGMA(x).(x:S|x)
1905		get_texpr_id(TID,ID),
1906	?	sum_or_mul_of_explicit_set(SETResult,SUMorMUL,R),!,
1907		equal_object_wf(SumResult,R,b_general_sum_or_mul_over_set,WF).
1908		b_general_sum_or_mul_over_set(IDs,SETResult,Expression,Type,LocalState,State,SumResult,WF,SUMorMUL) :-
1909		expand_custom_set_to_list_wf(SETResult,ESETResult,_Done,b_general_sum_or_mul_over_set,WF),
1910	?	b_sum_or_mul_over_list(ESETResult,IDs,Expression,Type,LocalState,State,SumResult,WF,SUMorMUL).
1911
1912		b_sum_or_mul_over_list(L,IDs,Expr,Type,LS,State,Result,WF,SUMorMUL) :-
1913		get_acc_base(SUMorMUL,Type,Acc),
1914		(Type = integer -> get_wait_flag0(WF,WF0) ; true), % for real: delay until values known
1915	?	b_sum_or_mul_over_list_acc(L,IDs,Expr,Type,LS,State,Acc,Result,WF,SUMorMUL,WF0).
1916
1917		:- block b_sum_or_mul_over_list_acc(-, ?, ?,?,?,?,?, ?,?,?,?).
1918		% better if list is fully known: no constraint propagation performed during computation !
1919		% for example: SIGMA(x).(x:{-1} \/ 1..30000|x+1) goes down from 2050 ms to 1210 ms
1920		b_sum_or_mul_over_list_acc([],_,_,Type,_,_,Acc,Result,_WF,_SUMorMUL,_) :-
1921	?	get_acc_result(Type,Acc,Result).
1922		b_sum_or_mul_over_list_acc([H|T],IDs,Expr,Type,LocalState,State,Acc,Result,WF,SUMorMUL,WF0) :-
1923		add_typed_vars_to_localstate(IDs,H,LocalState,NewLocalState),
1924		b_compute_expression(Expr,NewLocalState,State,HExprVal,WF),
1925		b_sum_or_mul_over_list_acc2(HExprVal,T,IDs,Expr,Type,LocalState,State,Acc,Result,WF,SUMorMUL,WF0).
1926
1927		:- block b_sum_or_mul_over_list_acc2(?,-, ?, ?,?,?,?,?, ?,?,?,?),
1928		b_sum_or_mul_over_list_acc2(?,?, ?, ?,?,?,?,-, ?,?,?,-),
1929		b_sum_or_mul_over_list_acc2(-,?, ?, ?,?,?,?,?, ?,?,?,-). % wait until T nonvar and either Acc & HExprVal known or WF0 set
1930		% purpose: try and remain in non-CLPFD mode as long as possible to avoid overflows,... (see eg. test 1642, 1708)
1931		b_sum_or_mul_over_list_acc2(HExprVal,T,IDs,Expr,Type,LocalState,State,Acc, Result,WF,SUMorMUL,WF0) :-
1932		(nonvar(T),nonvar(Acc),ground(HExprVal)
1933		-> % we can continue computing the system without constraint propagation; is faster
1934		get_value(Type,HExprVal,HVal),
1935		compose_acc(SUMorMUL,Acc,HVal,NewAcc),
1936		b_sum_or_mul_over_list_acc(T,IDs,Expr,Type,LocalState,State,NewAcc,Result,WF,SUMorMUL,WF0)
1937		; T==[], number(Acc), get_acc_base(SUMorMUL,Type,Acc) ->
1938		/* we have just a single element left and no operator has to be applied -> no need for clpfd treatment */
1939		equal_object_wf(HExprVal,Result,b_sum_or_mul_over_list_acc)
1940		; Type=real -> % no CLP(FD) treatment possible yet
1941		when(ground(HExprVal),
1942		b_sum_or_mul_over_list_acc2(HExprVal,T,IDs,Expr,Type,LocalState,State,Acc, Result,WF,SUMorMUL,WF0))
1943		; init_clp_acc(SUMorMUL,HExprVal,int(Acc),CLPAccumulator),
1944		b_sum_or_mul_over_list_clp(T,IDs,Expr,LocalState,State,CLPAccumulator,Result,WF,SUMorMUL)
1945		).
1946
1947		% add set comprehension solution ValueForTypedIDs as individual values for every TypedIDs to LocalState
1948		add_typed_vars_to_localstate(TypedIDs,ValueForTypedIDs,LocalState,NewLocalState) :-
1949		(flatten_pairs(TypedIDs,ValueForTypedIDs,ValAsList),
1950		add_typed_vars_to_localstate_aux(TypedIDs,ValAsList,LocalState,R)
1951		-> NewLocalState = R
1952		; add_internal_error('Call failed: ',add_typed_vars_to_localstate(TypedIDs,ValueForTypedIDs,LocalState,NewLocalState)),
1953		fail
1954		).
1955		% set comprehension results for {a,b,c|P} are nested like this ((a,b),c)
1956		% first argument only used for length (to know how deep the pairs are nested)
1957		flatten_pairs(L,Pairs,FlatList) :- flatten_pairs(L,Pairs,FlatList,[]).
1958		flatten_pairs([_],A) --> !, [A].
1959		flatten_pairs([_|T],(A,B)) --> flatten_pairs(T,A) ,[B].
1960		add_typed_vars_to_localstate_aux([],_,LS,LS).
1961		add_typed_vars_to_localstate_aux([TID],[H],LocalState,NewLocalState) :- !,
1962		get_texpr_id(TID,ID), get_texpr_type(TID,TYPE),
1963		add_typed_var_to_localstate(ID,H,TYPE,LocalState,NewLocalState).
1964		add_typed_vars_to_localstate_aux([TID1|Ids],[H1|Hs],LocalState,NewLocalState) :- !,
1965		get_texpr_id(TID1,ID1), get_texpr_type(TID1,TYPE),
1966		add_typed_var_to_localstate(ID1,H1,TYPE,LocalState,LS1),
1967		add_typed_vars_to_localstate_aux(Ids,Hs,LS1,NewLocalState).
1968
1969
1970		:- block b_sum_or_mul_over_list_clp(-, ?, ?,?,?, ?, ?,?,?).
1971		b_sum_or_mul_over_list_clp([],_, _,_,_, Acc, Result,_WF,SUMorMUL) :-
1972		finalise_clp(SUMorMUL,Acc,Result).
1973		b_sum_or_mul_over_list_clp([H|T],IDs,Expr,LocalState,State,Acc, Result,WF,SUMorMUL) :-
1974		add_typed_vars_to_localstate(IDs,H,LocalState,NewLocalState),
1975		b_compute_expression(Expr,NewLocalState,State,HExprVal,WF),
1976		compose_clp(SUMorMUL,HExprVal,Acc,NewAcc),
1977		b_sum_or_mul_over_list_clp(T,IDs,Expr,LocalState,State,NewAcc,Result,WF,SUMorMUL).
1978
1979		:- use_module(kernel_reals,[is_real/2]).
1980		get_acc_base(sum,integer,R) :- !, R=0.
1981		get_acc_base(sum,real,0.0).
1982		get_acc_base(mul,integer,R) :- !, R=1.
1983		get_acc_base(mul,real,1.0).
1984		get_acc_result(integer,Nr,int(Nr)).
1985		get_acc_result(real,Nr,Real) :- is_real(Real,Nr).
1986		get_value(integer,int(Val),Val) :- !.
1987		get_value(real,Real,Nr) :- is_real(Real,Nr).
1988
1989		compose_acc(sum,A,B,C) :- C is A+B.
1990		compose_acc(mul,A,B,C) :- C is A*B.
1991		init_clp_acc(sum,int(A),int(B),Res) :- (B==0 -> Res=[A] ; Res=[A,B]). % A always not ground
1992		init_clp_acc(mul,A,B,C) :- times(A,B,C).
1993		compose_clp(sum,int(A),Acc,NewAcc) :- NewAcc = [A|Acc].
1994		compose_clp(mul,A,B,C) :- times(A,B,C).
1995		:- use_module(clpfd_interface,[clpfd_sum/2]).
1996		finalise_clp(sum,Acc,int(Result)) :-
1997		clpfd_sum(Acc,Result). % using clpfd_sum can be much more efficient: no intermediate variables set up
1998		finalise_clp(mul,int(Acc),int(Acc)).
1999
2000		/* for if-then-else in Z: compute Then or Else,
2001		depending on the outcome of the predicate */
2002		:- block b_compute_if_then_else(-,?,?,?,?,?,?).
2003		b_compute_if_then_else(pred_true,Then,_Else,LocalState,State,Value,WF) :-
2004		opt_push_wait_flag_call_stack_info(WF,b_expr_call(if_then_body,Then),WF2),
2005	?	b_compute_expression(Then,LocalState,State,Value,WF2).
2006		b_compute_if_then_else(pred_false,_Then,Else,LocalState,State,Value,WF) :-
2007		opt_push_wait_flag_call_stack_info(WF,b_expr_call(if_else_body,Else),WF2),
2008	?	b_compute_expression(Else,LocalState,State,Value,WF2).
2009
2010		:- use_module(clpfd_interface,[clpfd_if_then_else/4]).
2011		% a more sophisticated treatment, can also work backwards forcing PredRes
2012		% examples:
2013		% x = IF a<10 THEN 0 ELSE 5 END & x:6..10 & a:1..23
2014		% see must_fail_clpfd_det 132 and 133
2015		% problematic if Else contains recursion; but then we should have WD condition
2016		b_clpfd_if_then_else(PredRes,Type,Then,Else,LocalState,State,Value,WF) :-
2017		get_wait_flag0(WF,WF0),
2018		b_clpfd_if_then_else_block(PredRes,WF0,Type,Then,Else,LocalState,State,Value,WF).
2019		:- block b_clpfd_if_then_else_block(-,-,?,?,?,?,?,?,?).
2020		b_clpfd_if_then_else_block(PredRes,_,Type,Then,Else,LocalState,State,Value,WF) :- var(PredRes),!,
2021		get_full_fd_value(Type,Value,FDValue),
2022		b_compute_expression(Then,LocalState,State,ThenValue,WF),
2023		get_full_fd_value(Type,ThenValue,FDThenValue),
2024		b_compute_expression(Else,LocalState,State,ElseValue,WF),
2025		get_full_fd_value(Type,ElseValue,FDElseValue),
2026		% TO DO: catch CLPFD overflow and use equality_objects
2027		clpfd_if_then_else(PredRes,FDThenValue,FDElseValue,FDValue).
2028		b_clpfd_if_then_else_block(pred_true,_,_Type,Then,_Else,LocalState,State,Value,WF) :-
2029		b_compute_expression(Then,LocalState,State,Value,WF).
2030		b_clpfd_if_then_else_block(pred_false,_,_Type,_Then,Else,LocalState,State,Value,WF) :-
2031		b_compute_expression(Else,LocalState,State,Value,WF).
2032
2033		:- use_module(b_global_sets,[get_global_type_value/3]).
2034		% try and get full_fd_value; true if full value can be translated to CLP(FD) value
2035		get_full_fd_value(global(T),FY,X) :- get_global_type_value(FY,T,X).
2036		get_full_fd_value(integer,int(X),X).
2037		get_full_fd_value(boolean,B,FD) :- kernel_equality:prop_eq_01(B,FD).
2038		% record with single field ?
2039
2040		can_get_full_fd_value(global(_)).
2041		can_get_full_fd_value(integer).
2042		can_get_full_fd_value(boolean).
2043
2044		% a slightly improved version over set_up_localstate (not sure it is really much faster):
2045		add_lazy_let_id_to_local_state(b(identifier(ID),_,_),Trigger,IdValue,LocalState,NewState) :-
2046		% should we delete any old occurence of ID in LocalState?
2047		NewState = [bind(ID,(Trigger,IdValue))|LocalState].
2048
2049		add_lazy_let_id_and_expression(Id,IdExpr,LocalState,InState,NewLocalState,WF) :-
2050		empty_avl(Ai),
2051		add_lazy_let_id_and_expression(Id,IdExpr,LocalState,InState,NewLocalState,WF,Ai).
2052		add_lazy_let_id_and_expression(Id,IdExpr,LocalState,InState,NewLocalState,WF,Ai) :-
2053		add_lazy_let_id_to_local_state(Id,Trigger,IdValue,LocalState,NewLocalState),
2054		lazy_compute_expression(Trigger,IdExpr,LocalState,InState,IdValue,WF,Ai).
2055
2056		/* for let-statements in Z and now in B: expand localstate by new variables and assign
2057		values to them ;
2058		now Expressions are evaluated in state *with* the new identifiers !
2059		*/
2060		%set_up_localstate_for_let_no_reuse(Ids,Exprs,LocalState,State,LetState,WF) :-
2061		% set_up_localstate(Ids,Vars,LocalState,LetState),
2062		% compute_let_expressions(Exprs,Vars,LocalState,State,WF).
2063		set_up_localstate_for_let(Ids,Vars,Exprs,LocalState,State,LetState,WF) :-
2064		set_up_localstate(Ids,Vars,LocalState,LetState),
2065		%external_functions:observe_variables(Ids,Vars),
2066	?	compute_let_expressions(Exprs,Vars,LetState,State,WF).
2067		compute_let_expressions([],[],_,_,_).
2068		compute_let_expressions([Expr|RestExprs],[Var|RestVars],LocalState,State,WF) :-
2069	?	b_compute_expression(Expr,LocalState,State,Value,WF),
2070		equal_object_optimized(Var,Value,compute_let_expressions),
2071	?	compute_let_expressions(RestExprs,RestVars,LocalState,State,WF).
2072
2073		set_up_localstate_for_global_let(Ids,Exprs,LocalState,State,LetState,WF) :-
2074		set_up_localstate(Ids,Vars,State,LetState),
2075		compute_let_expressions(Exprs,Vars,LocalState,LetState,WF).
2076
2077
2078		l_compute_field([],_LS,_S,[],_WF).
2079		l_compute_field([Field|T],LS,S,[FVal|CT],WF) :-
2080	?	b_compute_field(Field,LS,S,FVal,WF),
2081	?	l_compute_field(T,LS,S,CT,WF).
2082
2083		b_compute_field(field(Name,TypeOrVal),LocalState,State,field(Name,TypeOrFieldValue),WF) :-
2084	?	b_compute_expression(TypeOrVal,LocalState,State,TypeOrFieldValue,WF).
2085
2086
2087
2088		:- use_module(b_compiler).
2089
2090		/* :- type bsets_closure +--> closure(list(type(variable_id)),
2091		list(type(basic_type_descriptor)),type(boolean_expression)). */
2092
2093		:- assert_pre(b_interpreter:b_compute_comprehension_set(Parameters,Cond,_Info,LS,State,_R,_WF),
2094		(ground_check(Parameters),
2095		bsyntaxtree:check_if_typed_predicate(Cond),type_check(LS,store),type_check(State,store)) ).
2096
2097		:- assert_post(b_interpreter:b_compute_comprehension_set(_P,_C,_Info,_LS,_State,Val,_WF),
2098		(b_interpreter:value_type(Val))). %, nonvar(Val)
2099
2100
2101
2102		b_compute_comprehension_set_symbolic(Parameters,Condition,Info,LocalState,State,Result,WF) :-
2103		% a version which never expands the generated closure
2104	?	b_generate_closure_if_necessary(Parameters,Condition,LocalState,State,CResult,WF),
2105	?	(member(prob_annotation('SYMBOLIC'),Info)
2106		-> mark_closure_as_symbolic(CResult,CRS),Result=CRS
2107		; Result=CResult). % TODO: check if we need definitely_expand_this_explicit_set
2108		% we could catch Parameters = [TID], Condition = b(member(b(identifier(ID),_TYPE,_),SET)
2109		b_compute_comprehension_set(Parameters,Condition,Info,LocalState,State,Result,WF) :-
2110	?	b_generate_closure_if_necessary(Parameters,Condition,LocalState,State,CResult,WF),
2111		b_compute_comprehension_set_aux(CResult,Info,Result,WF).
2112
2113		:- use_module(clpfd_interface,[catch_clpfd_overflow_call2/2]).
2114		b_compute_comprehension_set_aux(CResult,_,Result,_WF) :-
2115		(var(CResult) ; \+ functor(CResult,closure,3) ),!,
2116		Result=CResult.
2117		b_compute_comprehension_set_aux(CResult,Info,Result,_WF) :-
2118	?	member(prob_annotation('SYMBOLIC'),Info),!,
2119		mark_closure_as_symbolic(CResult,CRS),Result=CRS.
2120		b_compute_comprehension_set_aux(CResult,_Info,Result,_WF) :-
2121		(preferences:get_preference(convert_comprehension_sets_into_closures,true),
2122		\+ definitely_expand_this_explicit_set(CResult)
2123		;
2124		dont_expand_symbolic_explicit_set(CResult)),!,
2125		Result=CResult.
2126		b_compute_comprehension_set_aux(CResult,Info,Result,WF) :-
2127		b_expand_compute_comprehension_set(CResult,Info,Result,WF).
2128
2129		b_expand_compute_comprehension_set(CResult,Info,Result,WF) :-
2130		% using just get_wait_flag1(b_compute_comprehension_set,WF,WF0), makes many benchmarks faster ; but e.g., test 268 fails; maybe we sholud pre-compute bexpr_variables ? and pass this to expand_only_custom_closure_global
2131		(preferences:preference(use_smt_mode,false)
2132		-> get_wait_flag(1000,b_compute_comprehension_set,WF,WF0) % ideally we should say WF0 = _ ; but for some benchmarks Rule_DB_SIGAREA_0024_ori.mch this is important to avoid expanding closures before other stuff fails
2133		% only in SMT mode can there be any benefit in expanding a non-ground closure (when it is a lambda closure)
2134		% => hence delay expansion longer, possibly detecting enumeration warnings while expanding
2135		% TO DO: for lambda closures with known domain: expand earlier !
2136		; get_wait_flag(2,b_compute_comprehension_set,WF,WF0)),
2137		kernel_objects:mark_as_to_be_computed(Result), % avoid that we instantiate this set (e.g., in check_element_of_wf: we will get a full description of the set later; see test 1353
2138		(var(WF0),var(Result) -> ground_value_check(CResult,CGr) ; true),
2139		block_compute_comprehension_set_aux(CResult,Info,Result,WF,WF0,CGr).
2140
2141		:- block block_compute_comprehension_set_aux(?,?,-,?,-,-).
2142		block_compute_comprehension_set_aux(CResult,Info,Result,WF,_WF0,_CGr) :-
2143		(
2144		nonvar(Result)
2145	?	-> equal_object_wf(CResult,Result,WF) % this may expand CResult or do other tests;
2146		% like emptyness test or symbolic equality;
2147		% if Result=[_|_] then the closure needs to be expanded anyhow, so need to try and keep symbolic
2148		;
2149	?	catch_clpfd_overflow_call2(
2150		on_enumeration_warning_with_continue(expand_only_custom_closure_global(CResult,Expansion,check_no_inf,WF),
2151		% check_no_inf: we know it is not definitely infinite; and we do not want warnings for virtual time-outs
2152		% an enumeration warning occured in the expansion scope: keep closure symbolic after all
2153		% NOTE: for this detection to work it is better to delay until the body is ground (CGr)
2154		% and not use a priority too low for WF0, otherwise Expansion will be var and enum warning may occur later
2155		b_compute_comprehension_set_sym_msg(CResult,Info,Result,WF) % Backup Call in case of enum warning
2156		,
2157		equal_object_wf(Result,Expansion,WF) % TrueContinuation
2158		% instantiating Result can trigger other code which fails and confuses on_enumeration_warning
2159		),
2160		b_compute_comprehension_set_sym(CResult,Result,WF)
2161		) % catch_clpfd_overflow_call2
2162		).
2163
2164		b_compute_comprehension_set_sym_msg(CResult,Info,Result,WF) :- CResult = closure(P,_T,B),
2165		silent_mode(off),
2166		% TO DO: should we check that this closure has not been constructed by ProB, e.g., for UNION ??
2167		% e.g., P = ['__RANGE_LAMBDA__'] what about '_zzzz_unary', '_zzzz_binary', '_prj_arg1__', ...
2168		% also: what if the enumeration warning has a pending_abort_error
2169		!,
2170		Msg = 'Keeping comprehension-set symbolic (you may want to use the /*@symbolic*/ pragma to prevent this message, unless it was due to a WD-Error), identifiers: ',
2171		(contains_info_pos(Info) -> Span=Info ; Span=B),
2172		add_message(b_compute_comprehension_set,Msg,P,Span),
2173		b_compute_comprehension_set_sym(CResult,Result,WF).
2174		b_compute_comprehension_set_sym_msg(CResult,_,Result,WF) :-
2175		b_compute_comprehension_set_sym(CResult,Result,WF).
2176
2177
2178		b_compute_comprehension_set_sym(CResult,Result,WF) :-
2179		mark_closure_as_symbolic(CResult,CRS), % prevent doing the same mistake again
2180		equal_object_wf(Result,CRS,b_compute_comprehension_set_sym,WF).
2181
2182
2183		:- use_module(closures,[construct_closure_if_necessary/4]).
2184		b_generate_forall_closure(Parameters,Condition,LocalState,State,Result,WF) :-
2185		split_names_and_types(Parameters,Names,Types),
2186		construct_closure(Names,Types,ClosurePred1,Result),
2187		(LocalState==[],State==[]
2188		-> ClosurePred = Condition % no lookups can be performed anyway; no need to compile
2189		; b_compiler:b_compile(Condition,Names,LocalState,State,ClosurePred,WF) ),
2190		add_texpr_infos(ClosurePred,[quantifier_kind(forall)],ClosurePred1). % info for call_stack
2191
2192
2193
2194		b_generate_closure_if_necessary(Parameters,Condition,LocalState,State,Result,WF) :-
2195		split_names_and_types(Parameters,Names,Types),
2196	?	b_compiler:b_compile(Condition,Names,LocalState,State,ClosurePred,WF),
2197		%print('COMPILED: '),translate:print_bexpr(ClosurePred),nl,
2198		construct_closure_if_necessary(Names,Types,ClosurePred,Result).
2199
2200
2201		:- public convert_list_of_expressions_into_sequence/2.
2202		convert_list_of_expressions_into_sequence(List,SeqValue) :-
2203		convert_list_of_expressions_into_sequence(List,1,Seq),
2204	?	equal_object_optimized(Seq,SeqValue,convert_list_of_expressions_into_sequence).
2205
2206		convert_list_of_expressions_into_sequence([],_,[]).
2207		convert_list_of_expressions_into_sequence([H|T],Cur,[(int(Cur),H)|ConvT]) :-
2208		C1 is Cur+1,
2209		convert_list_of_expressions_into_sequence(T,C1,ConvT).
2210
2211		convert_list_of_expressions_into_set_wf(ListOfElements,Set,Type,WF) :-
2212		list_of_expressions_is_ground(ListOfElements,Ground,OrderedListOfElements),
2213	?	convert_list_of_expressions_into_set1(Ground,OrderedListOfElements,Set,Type,WF).
2214		convert_list_of_expressions_into_set1(true,ListOfElements,Set,_Type,WF) :- %var(Set),
2215	?	\+ (ListOfElements = [H|_], is_symbolic_closure(H)), % list contains symbolic closures, do not try to expand to avl
2216		% see should_be_converted_to_avl_from_lists ?
2217		!, construct_avl_from_lists_wf(ListOfElements,AVLSet,WF),
2218	?	equal_object_wf(AVLSet,Set,convert_list_of_expressions_into_set1,WF).
2219		convert_list_of_expressions_into_set1(_,Seq,Set,Type,WF) :-
2220	?	kernel_objects:max_cardinality(Type,TypeMaxCard),
2221	?	convert_list_of_expressions_into_set2(Seq,1,[],Set,TypeMaxCard,WF).
2222
2223		% TO DO: sort elements : ground elements first
2224		convert_list_of_expressions_into_set2([],_,Set,Res,_,WF) :-
2225	?	equal_object_wf(Set,Res,convert_list_of_expressions_into_set2,WF).
2226		convert_list_of_expressions_into_set2([H|T],MaxSze,SetSoFar,OutSet,TypeMaxCard,WF) :-
2227		%kernel_objects:basic_type_set(Type,IntSet,MaxSze),
2228		check_set_lists_bounded(IntSet,TypeMaxCard,MaxSze),
2229		% TO DO: optimize; avoid traversing or typing elements over and over again
2230		% maybe add a max. sze argument to add_element
2231		add_element_wf(H,SetSoFar,IntSet,WF), % print(add_el(H,SetSoFar,IntSet)),nl,
2232		% TO DO: check if H in OutSet and keep track of which elements have already been covered in OutSet
2233		%check_element_of_wf(H,OutSet,WF), makes tests 114, 115, 118-120, 1063 fail ! % we could also call lazy_try_check_element_of if this turns out to be too expensive
2234		kernel_objects:lazy_try_check_element_of(H,OutSet,WF),
2235		M1 is MaxSze+1,
2236	?	convert_list_of_expressions_into_set2(T,M1,IntSet,OutSet,TypeMaxCard,WF).
2237
2238
2239		:- use_module(inf_arith).
2240
2241		% check that a set does not exceed a certain bound (to prevent infinite
2242		% or overeager enumeration of sets); Warning: will not check custom_explicit_set sizes
2243		check_set_lists_bounded(Set,TypeMaxCard,Bound) :-
2244		inf_arith:infmin(TypeMaxCard,Bound,Card),
2245		(is_inf_or_overflow_card(Card) -> true
2246		; Card<1 -> empty_set(Set)
2247		; check_set_bounded_aux(Set,Card)).
2248
2249		:- block check_set_bounded_aux(-,?).
2250		check_set_bounded_aux(CustomSet,_) :- is_custom_explicit_set(CustomSet,check_set_bounded_aux),!.
2251		check_set_bounded_aux([],_).
2252		check_set_bounded_aux([_|T],Card) :-
2253		C1 is Card-1,
2254		(C1=0 -> empty_set(T) ; check_set_bounded_aux(T,C1)).
2255
2256
2257
2258		% check if the list can be converted into AVL form; if not: re-order list so that ground elements are present first
2259		list_of_expressions_is_ground([],true,[]).
2260		list_of_expressions_is_ground([E|T],Ground,ResList) :-
2261		(should_be_converted_to_avl(E) -> ResList=[E|RT], list_of_expressions_is_ground(T,Ground,RT)
2262		; Ground=false,
2263		bring_ground_elements_forward(T,[E],ResList)
2264		).
2265
2266		bring_ground_elements_forward([],Acc,Acc).
2267		bring_ground_elements_forward([H|T],Acc,Res) :-
2268		(should_be_converted_to_avl(H) -> Res=[H|RT], bring_ground_elements_forward(T,Acc,RT)
2269		; bring_ground_elements_forward(T,[H|Acc],Res)).
2270
2271		:- use_module(kernel_card_arithmetic,[is_inf_or_overflow_card/1, safe_mul/3]).
2272		% compute cardinality of a list of parameters, such as for forall
2273		parameter_list_cardinality([],1).
2274		parameter_list_cardinality([b(identifier(_),BasicType,_)|T],Res) :-
2275	?	parameter_list_cardinality(T,TCard),
2276		(is_inf_or_overflow_card(TCard) -> Res=TCard
2277	?	; kernel_objects:max_cardinality(BasicType,Card),
2278		safe_mul(Card,TCard,Res)
2279		).
2280		% see also basic_type_list_cardinality, now moved to custom_explicit_sets
2281
2282		b_for_all(Parameters,Infos,LHS,RHS,LocalState,State,WF) :-
2283		get_wait_flag1(for_all(Parameters),WF,LWF), % hack: give total_function,... priority to set up domain/range
2284	?	b_for_all_aux(LWF,Parameters,Infos,LHS,RHS,LocalState,State,WF).
2285
2286		:- block b_for_all_aux(-,?,?,?,?,?,?,?).
2287		b_for_all_aux(_,Parameters,Infos,LHS,RHS,LocalState,State,WF) :-
2288		split_names_and_types(Parameters,Names,Types),
2289	?	b_compile(LHS,Names,LocalState,State,CLHS,WF),
2290	?	b_compile(RHS,Names,LocalState,State,CRHS,WF),
2291	?	b_for_all_aux2(Parameters,Names,Types,Infos,CLHS,CRHS,WF).
2292
2293		:- use_module(kernel_tools,[ground_bexpr/1, ground_bexpr_check/2]).
2294		b_for_all_aux2(_,_,_,_,LHS,RHS,_) :-
2295		(is_falsity(LHS) ; is_truth(RHS)),
2296		!. % quantifier always true
2297		b_for_all_aux2(Parameters,CParameters,CParameterTypes,Infos,LHS,RHS,WF) :-
2298		ground_bexpr(LHS),
2299	?	\+ obvious_enumeration(LHS,CParameters), % if we have an obvious (small) enumeration in the LHS it is often better simply to enumerate and check the RHS for every instance
2300		ground_bexpr(RHS), %print(not_exists_forall(Parameters,LHS,RHS)),nl,
2301		!,
2302		b_for_all_find_counter_example(Parameters,CParameters,CParameterTypes,Infos,LHS,RHS,WF).
2303		b_for_all_aux2(Parameters,CParameters,CParameterTypes,Infos,LHS,RHS,WF) :-
2304	?	parameter_list_cardinality(Parameters,ParCard),
2305		peel_implications(Parameters,ParCard,LHS,RHS, LHS2,RHS2),
2306	?	b_for_all_aux3(Parameters,ParCard,CParameters,CParameterTypes,Infos,LHS2,RHS2,WF).
2307
2308		b_for_all_aux3(Parameters,ParCard,CParameters,CParameterTypes,Infos,LHS,RHS,WF) :-
2309		%large_domain(Parameters,ParCard,LHS),
2310		is_infinite_or_very_large_explicit_set(closure(CParameters,CParameterTypes,LHS),10000000),
2311		% the domain is so large that we cannot possibly check all instances
2312		% in this case: we prefer to look for a counter example in the hope that the constraint solver can narrow down the search by combining LHS and not(RHS)
2313		!,
2314		perfmessage(forall,'Large forall domain: ',ParCard,Infos),
2315		ground_bexpr_check(LHS,LG),
2316		ground_bexpr_check(RHS,RG),
2317		when((nonvar(LG),nonvar(RG)),
2318		b_for_all_find_counter_example(Parameters,CParameters,CParameterTypes,Infos,LHS,RHS,WF)
2319		).
2320		b_for_all_aux3(Parameters,ParCard,_CP,_,Infos,LHS,RHS,WF) :-
2321		if(expand_forall_quantifier(Parameters,LHS,RHS,Infos,WF,ReificationVariable),
2322		(
2323		perfmessage(good(forall),'Reified forall by expanding into conjunction: ',LHS),
2324		ReificationVariable=pred_true),
2325		( % print(normal_forall(Parameters)),nl,
2326		b_generate_for_all_list_domain1(Parameters,ParCard,LHS,RHS,[],[],AllSolList,NewRHS,WF),
2327	?	expand_forall1(AllSolList,NewRHS,Parameters,WF)
2328		)).
2329
2330
2331		% a treatment of for all where we look for counter examples satisfying LHS & not(RHS)
2332		b_for_all_find_counter_example(Parameters,CParameters,CParameterTypes,Infos,LHS,RHS,WF) :-
2333		% if LHS is Parameters: avl_set(V) then we probably should not apply this rule ?
2334		create_negation(RHS,NegRHS),
2335		conjunct_predicates_with_pos_info(LHS,NegRHS,Pred0),
2336		% format('looking for: ~w ',[CParameters]), translate:print_bexpr(LHS),nl, translate:print_bexpr(NegRHS),nl,
2337		perfmessage(good(forall),translating_forall_into_not_exists(CParameters),LHS),
2338		add_texpr_infos(Pred0,[quantifier_kind(forall)],ClosureBody1), % for call_stack
2339		init_quantifier_wait_flag(WF,not(forall),Parameters,ParValues,Infos,LocalWF), % relevant for test 1904
2340		not_with_enum_warning_and_possible_delay(
2341		(custom_explicit_sets:b_test_closure(CParameters,CParameterTypes,ClosureBody1,ParValues,negative,LocalWF),
2342		perfmessage_bexpr(forall,forall_counter_example(CParameters,ParValues),LHS)
2343		),LocalWF, WF, forall(CParameters), Infos).
2344
2345		:- use_module(library(timeout),[time_out/3]).
2346		not_with_enum_warning_and_possible_delay(C,WF,OuterWF,PP,Span) :-
2347		get_preference(disprover_mode,true),
2348		% in disprover mode we do not track WD errors, no need to start_attach_inner_abort_errors
2349		!,
2350		% delay potentially expensive quantifications in the hope of finding other contradictions earlier
2351		if( (time_out(not_with_enum_warning(C,WF,PP,Span),20,TRes),TRes \== time_out),
2352		copy_wfe_from_inner_if_necessary(WF,OuterWF),
2353		(get_wait_flag(2,not_with_enum_warning_and_possible_delay,OuterWF,LWF), % which priority to use ??
2354		debug_println(19,delay_not_in_disprover_mode),
2355		not_with_enum_warning_delay(C,LWF,WF,OuterWF,PP,Span))).
2356		not_with_enum_warning_and_possible_delay(C,WF,OuterWF,PP,Span) :-
2357		start_attach_inner_abort_errors(Level,not_with_enum_warning),
2358		call_cleanup(not_with_enum_warning(C,WF,PP,Span),
2359		re_attach_pending_inner_abort_errors(Level,OuterWF,_)),
2360		copy_wfe_from_inner_if_necessary(WF,OuterWF).
2361
2362
2363		:- block not_with_enum_warning_delay(?,-,?,?,?,?).
2364		not_with_enum_warning_delay(C,_,WF,OuterWF,PP,Span) :-
2365		debug_println(19,trigger_not_with_enum_warning_delay),
2366		not_with_enum_warning(C,no_wf_available,PP,Span),
2367		copy_wfe_from_inner_if_necessary(WF,OuterWF).
2368
2369		:- use_module(avl_tools,[quick_avl_approximate_size/2]).
2370		obvious_enumeration(LHS,[Id]) :- % TO DO : allow multiple ids
2371		% TO DO: unify with is_for_all_set_membership_predicate code below
2372		TLHSMembership = b(LHSMembership,_,_),
2373	?	member_conjunct(TLHSMembership,LHS,_),
2374		obvious_enum_aux(LHSMembership,Id).
2375
2376		obvious_enum_aux(member(TID,b(value(VAL),_,_)),ID) :- get_texpr_id(TID,ID),
2377		nonvar(VAL), VAL = avl_set(AVL), % TO DO: also support interval closures ?
2378		quick_avl_approximate_size(AVL,Size),
2379		Size<256.
2380		%obvious_enum_aux(equal(LHS,RHS),ID) :- % stillposes problem for test 231, investigate
2381		% ( get_texpr_id(LHS,ID) -> get_texpr_expr(RHS,value(_))
2382		% ; get_texpr_id(RHS,ID) -> get_texpr_expr(LHS,value(_))).
2383		% % TODO: do we need to accept integer(.),... literals?
2384
2385		% expands forall quantifier and thus enables that we also propagate from right to left
2386		% This helps for test 1397 (HandshakeSimple_TotFun)
2387		% TO DO: directly call the code which tries to expand a forall quantifier
2388		expand_forall_quantifier(Parameters,LHS,RHS,Infos,WF,ReificationVariable) :-
2389		(preferences:preference(use_smt_mode,true) -> true
2390		; preferences:preference(solver_strength,SS), SS>9), % sometimes contrapositive checking maybe not useful; see test 1368
2391		% TO DO: investigate and provide more principled heuristic
2392		b_interpreter_check:b_check_forall_wf(Parameters,LHS,RHS,Infos,[],[],WF,ReificationVariable).
2393
2394		% rewrite !(x,..).( TRUTH => (LHS2 => RHS2)) into !(x,...).(LHS2 => RHS2)
2395		peel_implications(Parameters,ParCard,LHS,RHS, NewLHS,NewRHS) :-
2396		%print(forall),nl, print(Parameters),nl,print(LHS),nl,
2397		% this patterns occurs often in Event-B translations to classical B
2398		LHS=b(truth,_,_),
2399		RHS=b(implication(LHS2,RHS2),_,_), % TO DO: maybe also accept nested forall and then add to Parameters?
2400		(is_inf_or_overflow_card(ParCard) -> true ; ParCard>50),
2401		% larger bound than below: maybe user explicitly wants to expand it
2402		!,
2403		peel_implications(Parameters,ParCard,LHS2,RHS2, NewLHS,NewRHS).
2404		peel_implications(_,_,LHS,RHS, LHS,RHS).
2405
2406		b_generate_for_all_list_domain_nolwf(Parameters,LHS,RHS,LS,S,ForAllDomain,NewRHS,WF) :-
2407	?	parameter_list_cardinality(Parameters,ParCard),
2408		peel_implications(Parameters,ParCard,LHS,RHS, LHS2,RHS2),
2409		b_generate_for_all_list_domain1(Parameters,ParCard,LHS2,RHS2,LS,S,OForAllDomain,NewRHS,WF),
2410		optlist_to_list(OForAllDomain,ForAllDomain). % resolve any optional_value/2 items
2411
2412		% generate the domain of a Universally Quantified Formula as a list
2413		b_generate_for_all_list_domain1(Parameters,_ParCard,LHS,RHS,LS,S,ForAllDomain,NewRHS,WF) :-
2414		% optimized treatment for formulas of the form !x.(x:S => RHS) or !(x,y).(x|->y:S => RHS)
2415		% to do: expand to more formulas, such as !(x,y).(x:S & y:T => RHS)
2416		% or !y.(y:1..(n-1) & f(y)=TRUE => f(y+1)=TRUE) --> !y.(y:1..(n-1) => (f(y)=TRUE => f(y+1)=TRUE))
2417		% or we could try and reify set membership for small domains and trigger implication
2418		is_for_all_set_membership_predicate(LHS,Parameters,Set,Pattern,ParameterValues),!,
2419		perfmessages_bexpr_call(good(forall),['Detected forall set membership over ',Ps,': '],
2420		LHS,bsyntaxtree:def_get_texpr_ids(Parameters,Ps)),
2421		NewRHS=RHS,
2422		b_generate_set_for_all_domain(Set,LS,S,Pattern,ParameterValues,ForAllDomain,WF).
2423		b_generate_for_all_list_domain1(Parameters,ParCard,LHS,RHS,LS,S,ForAllDomain,NewRHS,WF) :-
2424		b_generate_forall_closure(Parameters,LHS,LS,S,Closure,WF), % POSSIBLY NO NEED TO COMPILE
2425		b_generate_for_all_domain2(Closure,Parameters,ParCard,LHS,RHS,ForAllDomain,NewRHS,WF).
2426
2427		b_generate_for_all_domain2(Closure,_Parameters,_,LHS,RHS,ForAllDomain,NewRHS,WF) :-
2428		(LHS=b(truth,pred,_) ; ground_value(Closure)),
2429		!, NewRHS=RHS, % nl,print('FORALL EXPAND: '),(ground_value(Closure) -> print(ground(_Parameters)),nl, print_bexpr(LHS),nl ; print('NONGROUND!!'),nl,print_bexpr(RHS),nl), %%
2430		b_expand_closure_forall_to_list(Closure,ForAllDomain,WF).
2431		b_generate_for_all_domain2(_,Parameters,_,LHS,RHS,ForAllDomain,NewRHS,WF) :-
2432		is_a_conjunct(LHS,_,_), % otherwise we have already checked for set_membership above !
2433		LHS_Membership = b(member(_,_),_,_), % TO DO: also allow conjuncts
2434	?	member_conjunct(LHS_Membership,LHS,RestLHS),
2435		% !(x). ( x:Set & RestLHS => RHS) ---> !(x).(x:Set => (RestLHS => RHS))
2436		is_for_all_set_membership_predicate(LHS_Membership,Parameters,Set,Pattern,ParameterValues),
2437	?	max_cardinality_ok_for_expansion(Set,100,[],[]), % TO DO: simplify LS,S argument <----
2438		!,
2439		% as we expand Set without RHS predicate, check if this is ok
2440		% indeed maximum cardinality of Set could be infinite !! !x.(x:NATURAL1 & x<N => P)
2441		% print('Splitting for all conjunct: '), print(Parameters),nl, print_bexpr(LHS_Membership),nl,print_bexpr(RestLHS),nl, %%
2442		perfmessage_bexpr(good(forall),'Splitting LHS of forall: ',LHS),
2443		NewRHS = b(implication(RestLHS,RHS),pred,[]), % TO DO: extract & join info
2444		b_generate_set_for_all_domain(Set,[],[],Pattern,ParameterValues,ForAllDomain,WF).
2445		b_generate_for_all_domain2(Closure,_Parameters,ParCard,LHS,RHS,ForAllDomain,NewRHS,WF) :-
2446		(is_inf_or_overflow_card(ParCard) -> true ; ParCard>8),
2447		!,
2448		NewRHS=RHS,
2449		perfmessage_bexpr(forall,'No optimisations applicable to forall (will delay until all variables are bound): ',LHS), % maybe we should generate this message only if ForAllDomain is var ?
2450		b_expand_closure_forall_to_list(Closure,ForAllDomain,WF).
2451		b_generate_for_all_domain2(_Closure,Parameters,ParCard,LHS,RHS,ForAllDomain,NewRHS,WF) :-
2452		NewLHS=b(truth,pred,[]), NewRHS=b(implication(LHS,RHS),pred,[]),
2453		b_generate_forall_closure(Parameters,NewLHS,[],[],Closure,WF),
2454		perfmessages_bexpr(good(forall),['Expanding forall with finite parameter type, card = ',ParCard,': '],LHS),
2455		b_expand_closure_forall_to_list(Closure,ForAllDomain,WF).
2456
2457		% code to decide whether a for all should be expanded if the
2458		% predicate contains a set membership predicate : !x.( (P & x:S & P') => Q)
2459		max_cardinality_ok_for_expansion(b(Expr,Type,_Info),Limit,LS,S) :- % which value to choose for Limit ??
2460	?	kernel_objects:max_cardinality(Type,TypeCard),
2461		( (number(TypeCard),TypeCard =< Limit) -> true ;
2462		max_cardinality_ok_for_expansion2(Expr,Limit,TypeCard,LS,S)).
2463
2464		max_cardinality_ok_for_expansion1(b(E,_,_),Limit,TC,LS,S) :-
2465		max_cardinality_ok_for_expansion2(E,Limit,TC,LS,S).
2466
2467		:- use_module(custom_explicit_sets,[efficient_card_for_set/3]).
2468
2469		max_cardinality_ok_for_expansion2(set_extension(E),Limit,_TC,_,_) :- !, length(E,Len), Len =< Limit.
2470		max_cardinality_ok_for_expansion2(interval(Up,Low),Limit,_TC,LS,S) :- !,
2471		get_integer(UpI,Up,LS,S), get_integer(LowI,Low,LS,S),
2472		UpI-LowI<Limit.
2473		max_cardinality_ok_for_expansion2(integer_set(GS),Limit,_TC,_LS,_S) :- !, b_global_set_cardinality(GS,Card),
2474		number(Card), Card =< Limit.
2475		max_cardinality_ok_for_expansion2(set_subtraction(A,_),Limit,TC,LS,S) :- !,
2476		max_cardinality_ok_for_expansion1(A,Limit,TC,LS,S).
2477		max_cardinality_ok_for_expansion2(image(RelA,_),Limit,TC,LS,S) :- !,
2478		max_cardinality_ok_for_expansion1(RelA,Limit,TC,LS,S).
2479		max_cardinality_ok_for_expansion2(function(_RelA,_),_Limit,_TC,_LS,_S) :- !,
2480		fail. % TO DO: we should look at the size of the range elements
2481		% max_cardinality_ok_for_expansion1(_RelA,_Limit,_TC,_LS,_S).
2482		max_cardinality_ok_for_expansion2(intersection(A,B),Limit,TC,LS,S) :- !,
2483		(max_cardinality_ok_for_expansion1(A,Limit,TC,LS,S) -> true ; max_cardinality_ok_for_expansion1(B,Limit,TC,LS,S)).
2484		max_cardinality_ok_for_expansion2(union(A,B),Limit,TC,LS,S) :- !,
2485		max_cardinality_ok_for_expansion1(A,Limit,TC,LS,S), max_cardinality_ok_for_expansion1(B,Limit,TC,LS,S).
2486		max_cardinality_ok_for_expansion2(range(A),Limit,TC,LS,S) :- !,
2487		max_cardinality_ok_for_expansion1(A,Limit,TC,LS,S).
2488		max_cardinality_ok_for_expansion2(domain(A),Limit,TC,LS,S) :- !,
2489		max_cardinality_ok_for_expansion1(A,Limit,TC,LS,S).
2490		max_cardinality_ok_for_expansion2(domain_restriction(_A,B),Limit,TC,LS,S) :- !,
2491		max_cardinality_ok_for_expansion1(B,Limit,TC,LS,S). % note: finite A does not guarantee finite result
2492		max_cardinality_ok_for_expansion2(domain_subtraction(_A,B),Limit,TC,LS,S) :- !,
2493		max_cardinality_ok_for_expansion1(B,Limit,TC,LS,S).
2494		max_cardinality_ok_for_expansion2(range_restriction(A,_B),Limit,TC,LS,S) :- !,
2495		max_cardinality_ok_for_expansion1(A,Limit,TC,LS,S). % note: finite B does not guarantee finite result
2496		max_cardinality_ok_for_expansion2(range_subtraction(A,_B),Limit,TC,LS,S) :- !,
2497		max_cardinality_ok_for_expansion1(A,Limit,TC,LS,S).
2498		max_cardinality_ok_for_expansion2(direct_product(A,B),Limit,TC,LS,S) :- !,
2499		max_cardinality_ok_for_expansion2(cartesian_product(A,B),Limit,TC,LS,S).
2500		max_cardinality_ok_for_expansion2(parallel_product(A,B),Limit,TC,LS,S) :- !,
2501		max_cardinality_ok_for_expansion2(cartesian_product(A,B),Limit,TC,LS,S).
2502		max_cardinality_ok_for_expansion2(cartesian_product(A,B),Limit,TC,LS,S) :- !,
2503		ILimit is Limit//2, ILimit>0, %use sqrt ?
2504		max_cardinality_ok_for_expansion1(A,ILimit,TC,LS,S),
2505		max_cardinality_ok_for_expansion1(B,ILimit,TC,LS,S).
2506		max_cardinality_ok_for_expansion2(value(S),Limit,_TC,_LS,_S) :- !,
2507		get_max_card_for_value(S,MaxCard),
2508		MaxCard =< Limit.
2509		max_cardinality_ok_for_expansion2(identifier(_ID),_Limit,TC,_LS,_S) :- !, number(TC).
2510		% TO DO: check if ID is fully defined; if so use card else accept as it will
2511		% probably be represented by a list and the forall constraints could be useful in finding ID's value
2512		% we have to store/compute ID anyway (could be infinite closure; hence check that TC is a number); a bit of a hack; is there a more principled way?
2513		max_cardinality_ok_for_expansion2(external_function_call(_,_),_,_,_,_) :- !,fail.
2514		max_cardinality_ok_for_expansion2(lazy_lookup_expr(_),_,_,_,_) :- !,fail.
2515		max_cardinality_ok_for_expansion2(record_field(_,_),_Limit,_TC,_LS,_S) :- !, fail.
2516		max_cardinality_ok_for_expansion2(E,Limit,TC,_LS,_S) :- functor(E,F,N),
2517		print(unknown_max_card(F/N,Limit,TC)),nl,fail.
2518
2519
2520		:- use_module(kernel_cardinality_attr,[clpfd_card_domain_for_var/3]).
2521
2522		get_max_card_for_value(S,MaxCard) :- var(S), !,
2523		clpfd_card_domain_for_var(S,_,Max), number(Max),
2524		MaxCard=Max.
2525		get_max_card_for_value([],R) :- !, R=0.
2526		get_max_card_for_value([_|T],R) :- !,get_max_card_for_value(T,TMax), R is TMax+1.
2527		get_max_card_for_value(S,Card) :- efficient_card_for_set(S,Card,C),!,
2528		call(C), number(Card).
2529
2530
2531		get_integer(X, b(Expr,integer,_),LS,S) :- get_integer2(Expr,X,LS,S).
2532		get_integer2(integer(X),X,_,_) :- number(X).
2533		get_integer2(identifier(Id),Val,LS,S) :- lookup_value(Id,LS,S,int(Val)), number(Val).
2534
2535		member_conjunct(Predicate,Conjunction,Rest) :-
2536		conjunction_to_list(Conjunction,List),
2537	?	select(Predicate,List,RestList),
2538		conjunct_predicates(RestList,Rest).
2539		% member_conjunct(Conj,Conj,b(truth,pred,[])). covered by case above
2540
2541		b_generate_set_for_all_domain(Set,LS,S,Pattern,ParameterValues,ForAllDomain,WF) :-
2542		b_compute_expression(Set,LS,S,EvSet,WF),
2543		expand_custom_set_to_list_wf(EvSet,ESet,_Done,b_generate_set_for_all_domain,WF),
2544		filter_and_convert_list_to_parameter_tuples(ESet,Pattern,ParameterValues,ForAllDomain).
2545
2546
2547		% check if it is a predicate of the form x:S or x:Sx & y:Sy ... which we can optimize
2548		% (i.e. compute SET before all values inside it are fully known)
2549		is_for_all_set_membership_predicate(LHS,Parameters,Set,Pattern,ParameterValues) :-
2550		% print('CHECK FORALL : '), translate:print_bexpr(LHS),nl,nl,
2551		get_texpr_ids(Parameters,ParIDs), % TO DO: call get_texpr_ids before
2552		same_length(ParIDs,ParameterValues),
2553		is_for_all_set_membership_predicate2(LHS,ParIDs,ParIDs,UnmatchedParIDs,Set,Pattern,ParameterValues,_UPV),
2554		UnmatchedParIDs=[].
2555
2556		% TODO: maybe also deal with existential quantifiers #x.(x|->y:Set) -> in Pattern x becomes free var
2557		is_for_all_set_membership_predicate2(LHS,All,ParIDs,UnmatchedParIDs,Set,Pattern,ParameterValues,UPV) :-
2558		is_member_test(LHS,Element,Set),
2559		!,
2560		identifiers_not_used_in_bexp(All,Set),
2561		convert_to_prolog_pattern_match(Element,ParIDs,UnmatchedParIDs,Pattern,ParameterValues,UPV).
2562		% TO DO: also allow failing pattern matches ?!; at least when splitting
2563		is_for_all_set_membership_predicate2(LHS,All,ParIDs,ParIDs2,Set,
2564		(Pat1,Pat2),ParameterValues,UPV) :-
2565		is_a_conjunct(LHS,LHS1,LHS2), % we could have something of the form x:Sx & y:Sy ...
2566		Set = b(cartesian_product(Set1,Set2),couple(T1,T2),[]),
2567		is_for_all_set_membership_predicate2(LHS1,All,ParIDs, ParIDs1,Set1,Pat1,ParameterValues,PV1),
2568		get_texpr_type(Set1,T1),
2569		!,
2570		is_for_all_set_membership_predicate2(LHS2,All,ParIDs1,ParIDs2,Set2,Pat2,PV1,UPV),
2571		get_texpr_type(Set2,T2).
2572
2573		% TO DO: maybe use a more general test to be reused in other places
2574		is_member_test(b(P,_,_),Element,Set) :- is_member_test_aux(P,Element,Set).
2575		is_member_test_aux(member(Element,Set),Element,Set).
2576		% also detect equalities: important for tests 28,29 after b_compiler can introduce equalities for singleton set memberships
2577		is_member_test_aux(equal(Element,SetVal),Element,Set) :- % TO DO : also other direction + other kinds of values ?
2578		SetVal = b(value(SV),T,I),
2579		Set = b(value([SV]),set(T),I).
2580
2581		identifiers_not_used_in_bexp(IDList,Expr) :-
2582		find_identifier_uses(Expr,[],Used),
2583		id_check(IDList,Used).
2584		id_check([],_).
2585		id_check([ID|T],Used) :-
2586		nonmember(ID,Used), !,
2587		id_check(T,Used).
2588
2589		% check if an expression can be converted to a Prolog linear unification/pattern match
2590		% give an list of free identifiers IDS
2591		convert_to_prolog_pattern_match(b(E,_,_),IDS,OutIDS,Pattern,VarsIn,VarsOut) :-
2592		convert_to_prolog_pattern_match2(E,IDS,OutIDS,Pattern,VarsIn,VarsOut).
2593
2594		convert_to_prolog_pattern_match2(identifier(ID),IDsIn,IDsOut,PatVariable,VarsIn,VarsOut) :-
2595		% check that the identifier is in the list of quantified variables and thus unbound
2596		!,
2597	?	(nth1(Nr,IDsIn,ID,IDsOut)
2598		-> nth1(Nr,VarsIn,PatVariable,VarsOut) % put fresh PatVariable in the Pattern
2599		),!.
2600		convert_to_prolog_pattern_match2(couple(ID1,ID2),IDS,OutIDS,Pattern,VarsIn,VarsOut) :-
2601		Pattern = (Pat1,Pat2),
2602		convert_to_prolog_pattern_match(ID1,IDS,RemIDS,Pat1,VarsIn,VarsInt),
2603		convert_to_prolog_pattern_match(ID2,RemIDS,OutIDS,Pat2,VarsInt,VarsOut).
2604		convert_to_prolog_pattern_match2(value(V),IDsIn,IDsOut,Pattern,VarsIn,VarsOut) :-
2605		can_be_used_for_unification(V), % check if we can use Prolog unification for equality
2606		!, Pattern=V, IDsOut=IDsIn, VarsIn=VarsOut.
2607		% TO DO: records?
2608
2609		% a pattern match code to be used with above; ensure we do not instantiate values
2610		pattern_match(PatVar,Val,Res) :- var(PatVar),!,PatVar=Val, Res=pred_true. % we have a free pattern variable
2611		pattern_match((Pat1,Pat2),(V1,V2),Res) :- !,
2612		pattern_match(Pat1,V1,R1), conjoin_simple(R1,R2,Res),
2613		pattern_match(Pat2,V2,R2).
2614		pattern_match(GroundPatVal,Val,Res) :- % we have a value that can_be_used_for_unification
2615		when( ?=(GroundPatVal,Val), (GroundPatVal=Val -> Res=pred_true ; Res=pred_false)).
2616
2617		:- block conjoin_simple(-,?,?). % TO DO: also allow second arg to unblock
2618		conjoin_simple(pred_true,X,X).
2619		conjoin_simple(pred_false,_,pred_false).
2620
2621		% similar to get_template(V,T,[])
2622		% but more restricted; we only accept those values where equality corresponds to Prolog unification
2623		% get_template is different and can assume normalized values, e.g., for empty set
2624		can_be_used_for_unification(V) :- var(V),!,fail.
2625		can_be_used_for_unification(int(V)) :- nonvar(V).
2626		can_be_used_for_unification(string(S)) :- ground(S).
2627		can_be_used_for_unification(fd(S,T)) :- ground(S), ground(T).
2628		can_be_used_for_unification(pred_false).
2629		can_be_used_for_unification(pred_true).
2630
2631
2632
2633		% take a list and a pattern and filter the values that do not match the Pattern
2634		% Unification with the Pattern also instantiates the ParameterValues
2635		% TODO: Instead of converting to a Prolog Unification we could use kernel_equality instead of pattern_match
2636		% but this is not obvious, as the pattern contains free variables and equality would never return true
2637		% we would need to apply kernel_equality only to the ground pattern parts
2638		:- block filter_and_convert_list_to_parameter_tuples(-,?,?,?).
2639		filter_and_convert_list_to_parameter_tuples([],_,_,[]).
2640		filter_and_convert_list_to_parameter_tuples([H|T],Pattern,ParameterValues,Res) :-
2641		copy_term((Pattern,ParameterValues),(CPat,CPV)),
2642		pattern_match(CPat,H,PredRes), % check if pattern matches new element H in set; careful not to instantiate H
2643	?	filter_and_convert_list_to_parameter_tuples_aux(PredRes,CPV,T,Pattern,ParameterValues,Res).
2644
2645		:- block filter_and_convert_list_to_parameter_tuples_aux(-,?,-,?,?,?).
2646		filter_and_convert_list_to_parameter_tuples_aux(PredRes,CPV,T,Pattern,ParameterValues,Res) :-
2647		var(PredRes),!, % we cannot decide yet whether the optional value is to be used or not
2648		Res = [optional_value(CPV,PredRes)|RT], % create constructor for map_optlist or similar
2649		filter_and_convert_list_to_parameter_tuples(T,Pattern,ParameterValues,RT).
2650		filter_and_convert_list_to_parameter_tuples_aux(PredRes,CPV,T,Pattern,ParameterValues,Res) :-
2651		(PredRes = pred_true % we have a match, universal quantifier applies to H
2652		-> Res = [CPV|RT]
2653		; % element of set does not match pattern; universal quantifier does not apply
2654		% ProB used to only accept non-failing pattern matches;
2655		% now we also accept tuples with static parts where Prolog unification can fail
2656		Res=RT
2657		),
2658	?	filter_and_convert_list_to_parameter_tuples(T,Pattern,ParameterValues,RT).
2659
2660		:- use_module(tools,[map_optlist/2,optlist_to_list/2]).
2661		:- use_module(library(lists),[maplist/3]).
2662		expand_forall1(OList,RHS,Parameters,WF) :-
2663		ground_bexpr(RHS), % because compiled this means we cannot do any constraint propagation on variables in RHS
2664		optlist_to_list(OList,List),
2665		ground_value(List), % ditto here: no variables on which we could do constraint propagation
2666		%% preferences:get_preference(double_evaluation_when_analysing,false), % causes test 1112 to fail TO DO:fix
2667		% otherwise we do not have a real redundancy wrt to not exists check
2668		debug_println(15,ground_forall_translating_into_not_exists(Parameters)),
2669		!,
2670		%kernel_waitflags:init_wait_flags(LocalWF,[expansion_context(forall,Parameters)]),
2671		init_quantifier_wait_flag(WF,forall,Parameters,ParResult,unknown,LocalWF),
2672		% Advantage over treatment below: NegRHS is interpreted only once
2673		% but we cannot provide any instantiations and there must not be any links with variables outside of the forall !!
2674		create_negation(RHS,NegRHS),
2675		not_with_enum_warning( (
2676		b_interpreter:test_forall_instance(NegRHS,Parameters,LocalWF,negative,ParResult), % can fail; if inconsistency detected in WF0
2677		kernel_waitflags:ground_det_wait_flag(LocalWF),
2678		member(ParResultInList,List), % check the body for every solution
2679		lists:maplist(kernel_objects:equal_object,ParResultInList,ParResult), % match parameters with the solutions of the domain
2680		kernel_waitflags:ground_wait_flags(LocalWF) % do not ground EF? ground_constraintprop_wait_flags ground_inner_wait_flags
2681		), LocalWF, forall(Parameters), RHS
2682		).
2683		expand_forall1(List,RHS,Parameters,WF) :-
2684	?	map_optlist(b_interpreter:test_forall_instance(RHS,Parameters,WF,positive),List).
2685
2686
2687		test_forall_instance(RHS,Parameters,WF,NegationContext,ParResult) :-
2688		LocalState=[],State=[],
2689	?	if(set_up_typed_localstate(Parameters,ParResult,_TypedVals,LocalState,NewLocalState,NegationContext),
2690		true,
2691		(nl,print(set_up_typed_localstate_failed(Parameters,ParResult,_,LocalState,NewLocalState)),nl,
2692		% it can happen that ParResult has constraints on it and that setting up the typing info detects the error
2693		% add_internal_error('Call failed: ', set_up_typed_localstate(Parameters,ParResult,_,LocalState,NewLocalState)),
2694		fail)),
2695	?	b_optimized_b_test_instance(RHS,NewLocalState,State,WF).
2696
2697		reification_relevant_for_op(implication(_,_)).
2698		reification_relevant_for_op(equivalence(_,_)).
2699		reification_relevant_for_op(disjunct(_,_)).
2700		% TODO: maybe check if a conjunct contains implication
2701		% relevant for example for: n=2000 & f:1..n-->BOOL & !i.(i:2..n => (f(i)=TRUE =>f(i-1)=FALSE)) & f(1)=TRUE
2702
2703		b_optimized_b_test_instance(RHS,NewLocalState,State,WF) :-
2704		get_texpr_expr(RHS,RE), reification_relevant_for_op(RE), % we will attempt reification
2705		attempt_reification,
2706		\+ always_well_defined(RHS), % this will prevent reification
2707		!,
2708		% try and compile in the hope that now the WD issue disappears:
2709		b_compiler:b_optimize(RHS,[],NewLocalState,State,NewRHS,WF),
2710		b_test_boolean_expression(NewRHS,NewLocalState,State,WF).
2711		b_optimized_b_test_instance(RHS,NewLocalState,State,WF) :-
2712	?	b_test_boolean_expression(RHS,NewLocalState,State,WF).
2713		% using b_test_inner_boolean_expression considerably slows down NQueens, Sudoku,...
2714		% WF=InnerWF. /* give the boolean expression a chance to do ground propagations first */
2715
2716
2717		% use this when the test boolean expression could be called with WF0 already set
2718		% give the inner expression a chance to do the deterministic stuff first
2719		b_test_inner_boolean_expression(Pred,LocalState,State,WF) :-
2720		kernel_waitflags:clone_wait_flags_from1(WF,GroundUponFinish,WF2),
2721		% set WF0 to variable to propagate deterministic infos first:
2722	?	b_test_boolean_expression(Pred,LocalState,State,WF2),
2723	?	kernel_waitflags:clone_wait_flags_from1_finish(WF,GroundUponFinish,WF2).
2724		% the same for testing negation of a predicate:
2725		b_not_test_inner_boolean_expression(Pred,LocalState,State,WF) :-
2726		kernel_waitflags:clone_wait_flags_from1(WF,GroundUponFinish,WF2),
2727		% set WF0 to variable to propagate deterministic infos first:
2728	?	b_not_test_boolean_expression(Pred,LocalState,State,WF2),
2729		kernel_waitflags:clone_wait_flags_from1_finish(WF,GroundUponFinish,WF2).
2730
2731		/* now the same as above; but without converting list of values into pairs */
2732		:- assert_pre(b_interpreter:b_expand_closure_forall_to_list(Closure,_Result,_WF),
2733		(nonvar(Closure), custom_explicit_sets:is_closure(Closure,_Parameters,_ParameterTypes,ClosureBody),
2734		nonvar(ClosureBody),
2735		bsyntaxtree:check_if_typed_predicate(ClosureBody))).
2736		:- assert_post(b_interpreter:b_expand_closure_forall_to_list(_Closure,Result,_WF),
2737		b_interpreter:value_type(Result)).
2738		b_expand_closure_forall_to_list(Closure,Result,WF) :- nonvar(Closure),
2739		Closure = closure(Parameters,ParameterTypes,ClosureBody),
2740		!,
2741		% print('Expand closure forall: '), translate:print_bexpr(ClosureBody),nl,
2742		% at the moment we may wait too long before expanding this closure
2743		% what if we have f(1) in the ClosureBody: in principle we only need to wait until f(1) known or even f sekeleton set up ? compilation now solves this issue ?
2744		(performance_monitoring_on,
2745		term_variables(ClosureBody,Vars),
2746		Vars \= []
2747		->
2748		perfmessagecall(delaying_forall(Parameters,vars(Vars),out(ParValues)),
2749		translate:print_bexpr(ClosureBody),ClosureBody)
2750		; true),
2751		ground_bexpr_check(ClosureBody,BodyGround),
2752		add_texpr_infos(ClosureBody,[quantifier_kind(forall)],ClosureBody1), % for call_stack
2753		delay_setof_list_wf( ParValues,
2754		%% (print_bt_message(expanding_forall_closure(Parameters,ClosureBody,ParValues)), %%
2755		custom_explicit_sets:b_test_closure(Parameters,ParameterTypes,ClosureBody1,
2756		ParValues,all_solutions,WF)
2757		%% ,print_bt_message(expanded(Parameters,ParValues)) ) %%
2758		,
2759		Result,
2760		BodyGround,WF).
2761		b_expand_closure_forall_to_list(Closure,Result,WF) :-
2762		add_internal_error('Illegal Call: ', b_expand_closure_forall_to_list(Closure,Result,WF)),
2763		fail.
2764
2765
2766		:- assert_pre(b_interpreter:set_up_typed_localstate(V,S,_), (list_skeleton(V),list_skeleton(S))).
2767		:- assert_post(b_interpreter:set_up_typed_localstate(_,_,R),list_skeleton(R)).
2768
2769		set_up_typed_localstate(Identifiers,InState,OutState) :-
2770	?	set_up_typed_localstate(Identifiers,_FreshVars,_TypedVals,InState,OutState,positive).
2771
2772		:- use_module(b_enumerate,[construct_typedval_infos/4]).
2773		set_up_typed_localstate([],[],[],State,State,_).
2774		set_up_typed_localstate([Identifier|IdRest],[Val|ValRest],[typedval(Val,Type,Var,TINFO)|TRest],
2775		% TO DO: add info field to typedval: source_span, and lambda_result/do_not_enumerate infos
2776		InState,OutState,NegationContext) :-
2777		% The other way round (first add Identfier, then IdRest) would be more efficient,
2778		% but we do it this way to keep compatibility with a previous version.
2779		% In specfile:compute_operation_effect, the arguments of an operation are in the same order than in the store
2780	?	set_up_typed_localstate(IdRest,ValRest,TRest,InState,InterState,NegationContext),
2781		def_get_texpr_id(Identifier,Var), get_texpr_type(Identifier,Type),
2782		get_texpr_info(Identifier,Info),
2783		triggers_enum_warning(Var,Type,Info,NegationContext,TriggersEnumWarning),
2784		get_texpr_info(Identifier,Infos),construct_typedval_infos(Var,Infos,TriggersEnumWarning,TINFO),
2785	?	add_typed_var_to_localstate(Var,Val,Type,InterState,OutState).
2786
2787		% same version; but with list of atomic ids and list of types
2788		set_up_typed_localstate2([],[],_,[],[],State,State,_).
2789		set_up_typed_localstate2([Var|IdRest],[Type|TyRest],Infos,[Val|ValRest],[typedval(Val,Type,Var,TINFO)|TRest],
2790		InState,OutState,NegationContext) :-
2791		% The other way round (first add Identfier, then IdRest) would be more efficient,
2792		% but we do it this way to keep compatibility with a previous version.
2793		% In specfile:compute_operation_effect, the arguments of an operation are in the same order than in the store
2794	?	set_up_typed_localstate2(IdRest,TyRest,Infos,ValRest,TRest,InState,InterState,NegationContext),
2795		triggers_enum_warning(Var,Type,Infos,NegationContext,TriggersEnumWarning),
2796		construct_typedval_infos(Var,Infos,TriggersEnumWarning,TINFO),
2797	?	add_typed_var_to_localstate(Var,Val,Type,InterState,OutState).
2798
2799		% possible values for NegationContext: positive, negative, all_solutions
2800		triggers_enum_warning(Id,Type,Info,all_solutions,Res) :- !,
2801		Res = trigger_throw(b(identifier(Id),Type,Info)).
2802		%triggers_enum_warning(Id,_Type,Info,NegationContext,trigger_false(Id)) :- % no longer used
2803		% NegationContext=positive, % when negated then success will occur if all possibilities have been tried out
2804		% memberchk(introduced_by(exists),Info),
2805		% %%((preferences:get_preference(disprover_mode,true),type_contains_unfixed_deferred_set(Type))-> fail % otherwise %finding a solution may depend on the size of the deferred set; true),
2806		% %% The Disprover now checks whether unfixed_deferred sets were involved; keeping track of implicit enumerations of %deferred sets is just too difficult
2807		% !.
2808		triggers_enum_warning(Id,Type,Info,_,trigger_true(b(identifier(Id),Type,Info))).
2809
2810
2811		add_typed_var_to_localstate(Var,Val,Type,InState,OutState) :-
2812		add_var_to_localstate(Var,Val,InState,OutState),
2813		%%when(ground(Val), (print(' ++ '),print(Var),print(' ---> '), print(Val),nl)),
2814	?	kernel_objects:basic_type(Val,Type). %% ,print(ok(Val)),nl.
2815
2816		/*
2817		xxb_test_exists(Parameters,Condition,Infos,LocalState,State,WF) :-
2818		b_check_boolean_expression(b(exists(Parameters,Condition),pred,Infos),LocalState,State,WF,NR),
2819		get_exists_used_ids(Parameters,Condition,Infos,Used),lookup_values_if_vars(Used,LocalState,State,WaitVars),
2820		\+ ground(WaitVars),
2821		!,
2822		debug_println(9,unfolding_exists(Parameters)), print(unfolding(Parameters)),nl,
2823		%translate:print_bexpr(Condition),nl, print(State),nl, print(LocalState),nl,nl,
2824		NR=pred_true. %, print(set_res(pred_true)),nl.
2825		% if enabled it slows down: ./probcli examples/EventBPrologPackages/SET_Game/SET_GAM_Sym_NoSet20_mch.eventb -mc 10000000 -p SYMMETRY_MODE hash -p TIME_OUT 7000 -p CLPFD TRUE -df -goal "n=18" -p MAX_OPERATIONS 20 -strict -expcterr goal_found
2826		*/
2827
2828		b_test_exists(Parameters,Condition,Infos,LocalState,State,WF) :-
2829		get_wait_flag0(WF,WF0),
2830	?	b_test_exists(WF0,Parameters,Condition,Infos,LocalState,State,WF).
2831
2832		:- block b_test_exists(-,?,?, ?,?,?,?).
2833		b_test_exists(_LWF,Parameters,Condition,Infos,LocalState,State,WF) :-
2834		if((attempt_reification, % what if there is a wd_condition attached to Condition?
2835		b_interpreter_check:b_check_exists_wf(Parameters,Condition,Infos,LocalState,State,WF,ReificationVariable)),
2836		% try and expand quantifiers of small cardinality; see also expand_forall_quantifier
2837		% tested in test 1452
2838		(debug_println(9,expanded_exists(Parameters)),
2839		ReificationVariable=pred_true),
2840	?	b_test_exists_wo_expansion(Parameters,Condition,Infos,LocalState,State,WF)).
2841
2842		%attempt_reification :- preferences:preference(use_clpfd_solver,true),!. % all tests seem to pass
2843		attempt_reification :- preferences:preference(use_smt_mode,true),!.
2844		attempt_reification :- preferences:preference(solver_strength,SS), SS>9.
2845		% TO DO: maybe take context into account: setup constants, becomes such, ... allow_skipping_over_components/reset_component_info(true)
2846
2847		:- use_module(kernel_tools,[bexpr_variables/2, value_variables/3]).
2848
2849		% we treat the existential quantifier without expansion into a disjuncition aka reification
2850		b_test_exists_wo_expansion(Parameters,Condition,Infos,LocalState,State,WF) :-
2851		%print(test_exists(Parameters,Infos)),nl,portray_waitflags(WF),nl,
2852	?	(preference(lift_existential_quantifiers,true) ; member(allow_to_lift_exists,Infos)),
2853		!, % we enumerate the exists normally; treat it just like an ordinary predicate
2854		% lifting may generate multiple solutions; but avoids delaying enumeration of quantified parameters
2855		% print('*Lifting existential quantifier: '), translate:print_bexpr(Condition),nl,
2856	?	set_up_typed_localstate(Parameters,ParaValues,TypedVals,LocalState,NewLocalState,positive),
2857		copy_wf_start(WF,b_test_exists_wo_expansion,CWF),
2858		opt_push_wait_flag_call_stack_quantifier_info(CWF,exists,Parameters,ParaValues,Infos,CWF2),
2859	?	b_test_boolean_expression(Condition,NewLocalState,State,CWF2),
2860		% often we do not need to enumerate TypedVals; they can be derived, but we could have #y.(y>x) and need to enum y
2861		b_tighter_enumerate_values_in_ctxt(TypedVals,Condition,CWF2),
2862	?	copy_wf_finish(WF,CWF2). % moving this before tighter_enum may mean that we have more precise ranges; but this can be counter-productive (e.g., for test 1162 unless we strengthen the useless enum analysis)
2863		b_test_exists_wo_expansion(Parameters,Condition,Infos,LocalState,State,WF) :-
2864		get_exists_used_ids(Parameters,Condition,Infos,Used),
2865		% IT IS IMPORTANT THAT THE USED INFO IS CORRECT ; otherwise the WaitVars will be incorrect
2866		% The used_ids info does not include the Parameters of the existential quantifier !
2867	?	set_up_typed_localstate(Parameters,ParaValues,TypedVals,LocalState,NewLocalState,positive),
2868		lookup_values_if_vars(Used,LocalState,State,WaitVarsState), % TO DO: we could use b_compiler instead
2869		% What if the Condition was compiled and now contains a previously used_variable inside a closure/value ?
2870		%term_variables((Condition,WaitVarsState),WaitVars), % this can be expensive when we have large data values (see rule_RVF219/rule_RVF219_compo.mch)
2871		bexpr_variables(Condition,CondVars),
2872		value_variables(WaitVarsState,CondVars,WaitVars),
2873		% now determine which WaitVars are really worth waiting for, e.g., do not wait for res in #x.(x:E & ... res=min(f(x)))
2874		% relevant tests: 1868, 1194, 383, 1642, 1708, 1003, 1080, 1081, 1943
2875		(remove_ids_defined_by_equality(WaitVars,LocalState,State,Infos,RealWaitVars) -> RemovedVars=true
2876		; RealWaitVars = WaitVars, RemovedVars=false),
2877		opt_push_wait_flag_call_stack_quantifier_info(WF,exists,Parameters,ParaValues,Infos,WF2),
2878		create_inner_wait_flags(WF2,expansion_context(b_test_exists,Parameters),LocalWF), % we are creating inner waitflags here as the exist will wait anyway; LocalWF shares just WFE flag with WF
2879	?	b_test_boolean_expression(Condition,NewLocalState,State,LocalWF), /* check Condition */
2880	?	ground_det_wait_flag(LocalWF), % print('det no contradiction'),nl,flush_output,
2881		b_tighter_enumerate_values_in_ctxt(TypedVals,Condition,LocalWF), % will not yet enumerate
2882		(% we could treat allow_to_lift_exists also here by setting ESWF=1; but 1162 then fails
2883		get_preference(data_validation_mode,true),
2884		not_generated_exists_paras(Parameters) % generated exists, e.g., for relational composition can lead to virtual timeouts, cf Thales_All/rule_zcpa2.mch in test 2287
2885		-> get_wait_flag(50000,b_test_exists(Parameters),WF,ESWF) % 100000 sufficient for test 1945; 869 for rule_CHAMPS in private_examples/ClearSy/2023
2886		; get_enumeration_starting_wait_flag(b_test_exists(Parameters),WF,ESWF)), %% TO DO: get flag when enumeration of infinite type starts; maybe if domain of exists is small we can start enumerating earlier ?? <-> relation with lifting exists in closure expansion heuristic
2887		when((nonvar(ESWF);ground(RealWaitVars)),b_enumerate_exists(ESWF,RemovedVars,WaitVars,Parameters,Infos,LocalWF,WF)).
2888
2889
2890		:- use_module(tools,[remove_variables/3]).
2891		:- use_module(kernel_tools,[value_variables/2]).
2892		% if we have #x.( P & y = E(x)) we do not have to wait for y to be known
2893		remove_ids_defined_by_equality(WaitVars,LocalState,State,Infos,RealWaitVars) :- WaitVars \== [],
2894		memberchk(used_ids_defined_by_equality(Ideq),Infos),
2895		Ideq = [ID1|_], % currently we only look at one used_id defined by equality,
2896		% we could have #x.(P & y=E(z) & z=E(y)): TODO: improve computation in ast_cleanup
2897		(memberchk(bind(ID1,VAL),LocalState) -> true ; memberchk(bind(ID1,VAL),State)),
2898		value_variables(VAL,VARS),
2899		remove_variables(WaitVars,VARS,RealWaitVars),
2900		debug_println(9,removed_ids_def_by_equality(WaitVars,ID1,RealWaitVars)).
2901
2902
2903		b_enumerate_exists(ESWF,RemovedVars,WaitVars,Parameters,Infos,LocalWF,WF) :-
2904		%print(enum_exists(ESWF,RemovedVars,WaitVars,Parameters,LocalWF,WF)),nl,
2905		((RemovedVars=false,var(ESWF) ; % WaitVars guaranteed to be ground
2906		ground(WaitVars)) % TODO: replace this by an optimised version of ground check
2907		-> get_idle_flag(Parameters,WF,LWF),
2908		/* allow all other co-routines waiting on WaitVars to complete */
2909		/* Note however: if WF grounding as triggered two non-deterministic co-routines this
2910		will allow the other non-determinism to run first, duplicating the number of calls !
2911		This has been fixed by storing seperate waitflag variables for same prio in kernel_waitflags
2912		TODO: However, for enumeration of FD variables this might still happen and lead to duplication of
2913		calls to b_enumerate_exists_aux_ground
2914		*/
2915		%print(get_idle(Parameters,WaitVars)),nl, %kernel_waitflags:portray_waitflags(WF),nl,nl,
2916		b_enumerate_exists_aux_ground(LWF,WaitVars,Parameters,Infos,LocalWF,WF)
2917		; debug_println(9,semi_lifting_exists(ESWF,Parameters)),
2918		% add_message_wf(exists,'Semi-lifting exists:',Parameters,Parameters,WF),portray_waitflags(LocalWF),nl,
2919		kernel_waitflags:copy_waitflag_store(LocalWF,WF) % outer WF will now drive enumeration
2920		% Note: in case a LET has been moved inside and replaced this may lead to duplication
2921		).
2922
2923		:- if(environ(prob_safe_mode,true)).
2924		get_idle_flag(Parameters,WF,LWF) :- kernel_waitflags:get_idle_wait_flag(b_enumerate_exists(Parameters),WF,LWF),
2925		(var(LWF) -> true ; add_internal_error('Illegal idle waitflag for exists:',get_idle_flag(Parameters,WF,LWF))).
2926		:- else.
2927		get_idle_flag(Parameters,WF,LWF) :- kernel_waitflags:get_idle_wait_flag(b_enumerate_exists(Parameters),WF,LWF).
2928		:- endif.
2929
2930		:- block b_enumerate_exists_aux_ground(-,?,?,?,?,?).
2931		b_enumerate_exists_aux_ground(_,_WaitVars,Parameters,Infos,LocalWF,_WF) :-
2932		/* Note: this does a local cut: so it is important
2933		that all conditions are fully evaluated before performing the cut ; otherwise
2934		solutions will be lost */
2935		% print_bt_message('ENUMERATE EXISTS'(_Parameters)),nl, % portray_waitflags(_WF),
2936		if(ground_wait_flags_for_exists(Parameters,LocalWF),true,
2937		(perfmessage(exists,'Late bound exists failed: ',Parameters,Infos),fail)).
2938
2939
2940		ground_wait_flags_for_exists(Parameters,LocalWF) :-
2941	?	\+ enumeration_warning_occured_in_error_scope,
2942		get_current_error_scope(Level),
2943	?	\+ error_manager:throw_error(Level,_,_),
2944		!, % current scope is already clean, no need to enter a fresh one
2945		ground_wait_flags_for_exists2(Parameters,LocalWF,Level).
2946		ground_wait_flags_for_exists(Parameters,LocalWF) :-
2947		enter_new_clean_error_scope(Level),
2948		% Note: see {x|x:1..10 & #y.(y>x & y*y >10)} in test 2210:
2949		% we do not want to throw enum warnings even if the outer scope does in case a solution is found
2950		% NOTE: if this engenders an enumeration warning: it may have been better to enumerate the outer WF first ?! : but as WaitVars are ground, so only failure of outer WF could help us here in preventing enumeration warning
2951		call_cleanup(ground_wait_flags_for_exists2(Parameters,LocalWF,Level),
2952		exit_error_scope(Level,_,ground_wait_flags_for_exists)).
2953
2954		ground_wait_flags_for_exists2(_Parameters,LocalWF,Level) :-
2955	?	(ground_constraintprop_wait_flags(LocalWF)
2956		-> % local cut: one solution is sufficient.
2957		clear_enumeration_warning_in_error_scope(Level)
2958		% ; %print(fail),nl, % do not clear enumeration warnings fail
2959		).
2960
2961
2962		:- use_module(b_ast_cleanup,[check_used_ids_info/4]).
2963		get_exists_used_ids(Parameters,Condition,Infos,Used) :-
2964		preference(prob_safe_mode,true),!,
2965	?	(select(used_ids(Used),Infos,Rest)
2966		-> check_used_ids_info(Parameters,Condition,Used,exists), %% comment in to check used_ids field
2967		(member(used_ids(_),Rest)
2968		-> add_internal_error('Multiple used_ids info fields:',Parameters:Infos) ; true)
2969		;
2970		add_internal_error(
2971		'Expected information of used identifiers in exists information',Parameters:Infos),
2972		bsyntaxtree:find_identifier_uses(Condition, [], Used)
2973		).
2974		get_exists_used_ids(Parameters,Condition,Infos,Used) :-
2975	?	member(used_ids(Used),Infos) -> true
2976		;
2977		add_internal_error(
2978		'Expected information of used identifiers in exists information',Parameters:Infos),
2979		bsyntaxtree:find_identifier_uses(Condition, [], Used).
2980		% what if we call test_exists for a negated universal quantifier ??
2981
2982
2983
2984
2985		:- use_module(kernel_tools,[ground_state/1]).
2986		/* the following causes performance problems with examples/B/Mathematical/GraphIso/CheckGraphIsomorphism
2987		and with lausanne.mch in SMT mode */
2988		b_not_test_exists(Parameters,Condition,Infos,LocalState,State,_,WF) :-
2989		preferences:preference(use_smt_mode,true),
2990		is_a_conjunct(Condition,LHS,RHS),
2991		(\+ ground_state(LocalState) ; \+ ground_state(State)),
2992		% TO DO: check if any of the variables in Condition are not ground
2993		% TO DO: check if used_ids exist in Infos ? memberchk(used_ids(_),Infos),
2994		!,
2995		%print(translating_not_exists_into_forall),nl,print(' '),print_bexpr(LHS),nl, print('=> '),print_bexpr(RHS),nl,
2996		(is_for_all_set_membership_predicate(RHS,Parameters,_Set,_Pattern,_ParameterValues),
2997		\+ is_for_all_set_membership_predicate(LHS,Parameters,_,_,_)
2998		-> LLHS=RHS, RRHS=LHS % swap LHS and RHS; TO DO: search for membership predicate inside LHS,RHS !!
2999		; LLHS=LHS, RRHS=RHS
3000		),
3001		safe_create_texpr(negation(RRHS),pred,NegRHS),
3002		b_for_all(Parameters,Infos,LLHS,NegRHS,LocalState,State,WF).
3003		b_not_test_exists(Parameters,Condition,Infos,[],[],no_compile,WF) :- !,
3004		% already compiled in is_empty_closure_wf
3005		ground_bexpr_check(Condition,Ground),
3006		b_not_test_exists_aux(Ground,Parameters,Condition, Infos, WF).
3007		b_not_test_exists(Parameters,Condition,Infos,LocalState,State,_,WF) :-
3008		% compile to remove dependency on unused parts of State+LocalState; will make it delay less below
3009		def_get_texpr_ids(Parameters,ParaIDs),
3010		%% print(b_not_test_exists(ParaIDs)),nl, print(state(LocalState,State)),nl, %%
3011	?	b_compiler:b_compile(Condition,ParaIDs,LocalState,State,CompiledCond,WF),
3012		(is_truth(CompiledCond) -> fail
3013		; is_falsity(CompiledCond) -> true
3014		% TO DO: we could detect equalities that will always succeed (but be careful for WD issues)
3015		; ground_bexpr_check(CompiledCond,Ground),
3016		b_not_test_exists_aux(Ground,Parameters,CompiledCond, Infos, WF)
3017		).
3018
3019		:- block b_not_test_exists_aux(-,?,?,?,?).
3020		b_not_test_exists_aux(_,Parameters,CompiledCond,Infos,WF) :-
3021		% getting an idle waitflag considerably slows down test 1739; see also ClearSy/2019_Aug/call_residue/rule_erreur.mch
3022		% slow down no longer the case with the new waitflag implementation
3023		kernel_waitflags:get_idle_wait_flag(b_not_test_exists_aux(Parameters),WF,LWF),
3024		% allow pending co-routines to complete
3025		b_not_test_exists_aux2(LWF,Parameters,CompiledCond,Infos,WF).
3026		:- block b_not_test_exists_aux2(-,?,?,?,?).
3027		b_not_test_exists_aux2(_,Parameters,CompiledCond,Infos,WF) :-
3028		% no need to create inner waitflag: we enumerate fully below: create_inner_wait_flags(WF,b_not_test_exists(Parameters),LocalWF),
3029		%init_wait_flags(LocalWF,[expansion_context(b_not_not_test_exists,Parameters)]),
3030		init_quantifier_wait_flag(WF,not(exists),Parameters,ParaResult,Infos,LocalWF),
3031		not_with_enum_warning(
3032		b_interpreter:b_not_not_test_exists_aux(Parameters,ParaResult,CompiledCond,LocalWF),
3033		LocalWF, CompiledCond, % was not_exists(Parameters), the not_exists quantifier call is on call_stack now
3034		CompiledCond),
3035		copy_wfe_from_inner_if_necessary(LocalWF,WF). % for the case that the negated call has found abort errors and WFE was not grounded
3036		b_not_not_test_exists_aux(Parameters,ParaResult,CompiledCond,LocalWF) :-
3037	?	b_interpreter:set_up_typed_localstate(Parameters,ParaResult,TypedVals,[],NewLocalState,negated),
3038		% delay generation of WD error messages until outer WFE flag set
3039	?	b_interpreter:b_test_boolean_expression(CompiledCond,NewLocalState,[],LocalWF), % check Condition
3040		b_tighter_enumerate_values_in_ctxt(TypedVals,CompiledCond,LocalWF),
3041	?	ground_inner_wait_flags(LocalWF). % does not always ground WFE if abort is pending in which case not_with_enum_warning also does not fail and keeps the co-routines
3042		% pending co-routines will be discarded by negation !
3043
3044
3045		/* --------------------------------- */
3046
3047		value_type(_X). % only used in post_conditions (assert_post)
3048		/*
3049		value_type(X) :- nonvar(X),
3050		(X = value(_) ; X = global_set(_) ;
3051		X = global_constant(_) ; X = term(_)).*/
3052
3053
3054		% look up identifiers in store, if the identifier
3055		% is not in the store, assume it's a constant and ignore it
3056		% used for determining wait variables for existential quantifier
3057		% TO DO: better deal with CSE @identifiers ?
3058		lookup_values_if_vars([],_,_,[]).
3059		lookup_values_if_vars([Id|IRest],LocalStore,Store,Values) :-
3060		( lookup_value(Id,LocalStore,Store,Val)
3061		-> (force_evaluation_of_lazy_value(Id,Val,RealVal)
3062		-> Values = [RealVal|VRest]
3063		; Values = [Val|VRest])
3064		; Values = VRest),
3065		lookup_values_if_vars(IRest,LocalStore,Store,VRest).
3066
3067		force_evaluation_of_lazy_value(Id,Value,RealVal) :- nonvar(Value), Value=(Trigger,RealVal),
3068		var(Trigger),
3069		get_preference(use_common_subexpression_elimination,true),
3070		is_lazy_let_identifier(Id),
3071		!,
3072		Trigger=pred_true. % force evaluation, as the exists will otherwise delay/flounder
3073		% Warning: this means that outer lazy_let_expressions inside an exists should be well-defined (WD)
3074
3075
3076		/* will not generate error messages; used for CSP||B when we don't know if something is a B variable or not */
3077		/* TO DO: add peel_prefix for global_sets and constants ?? */
3078		try_lookup_value_in_store_and_global_sets(Id,State,Val) :-
3079		(lookup_value(Id,State,RVal) -> RVal=Val
3080		; b_global_sets:lookup_global_constant(Id,VGC) -> Val = VGC
3081		; b_global_set_or_free_type(Id,_AnyType,Value) -> Val=Value /* global set evaluates to itself */
3082		).
3083
3084
3085		lookup_value_in_store_and_global_sets_wf(Id,Type,LocalState,State,Val,Span,WF) :-
3086		(lookup_value_with_span_wf(Id,LocalState,State,RVal,Span,WF)
3087		-> RVal=Val
3088		; lookup_value_in_global_sets_wf(Id,Type,Val,LocalState,State,Span,WF)
3089		).
3090
3091		lookup_value_in_global_sets_wf(Id,Type,Val,LocalState,State,Span,WF) :-
3092		(b_global_sets:lookup_global_constant(Id,VGC)
3093		-> Val=VGC
3094	?	; (b_global_set_or_free_type(Id,Type,Value)
3095		-> Val = Value /* global set evaluates to itself */
3096		; ((member(bind(Id,_),LocalState) ; member(bind(Id,_),State))
3097		-> Msg1 = 'Cannot determine value for identifier '
3098		; Msg1 = 'Cannot find identifier '
3099		),
3100		append(LocalState,State,LSS),
3101		translate:translate_bstate_limited(LSS,StateInfo),
3102		ajoin([Msg1,Id,':'],Msg),
3103		add_error_wf(identifier_not_found,Msg,StateInfo,Span,WF),
3104		fail % Val = term(Id) /* Val=fail */
3105		)
3106		).
3107
3108		:- use_module(probsrc(kernel_freetypes),[registered_freetype/2, registered_freetype_case_value/3]).
3109	?	b_global_set_or_free_type(Id,_,global_set(Id)) :- b_global_set(Id).
3110		b_global_set_or_free_type(Id,_,freetype(Id)) :- registered_freetype(Id,_).
3111		b_global_set_or_free_type(Id,Type,Value) :-
3112		registered_freetype_case_value(Id,Type,Value). % to instantiate the type parameters we also need the TypeId
3113		% TODO: we could also register Event-B destructors and look them up here
3114
3115		/* -----------------------------*/
3116		/* b_compute_expressions */
3117		/* -----------------------------*/
3118
3119		b_compute_expressions([], _, _, [],_WF).
3120		b_compute_expressions([EXPRsHd|EXPRsTl],LocalState,InState,[ValHd|ValTl],WF) :-
3121	?	b_compute_expression(EXPRsHd,LocalState,InState,ValHd,WF),
3122	?	b_compute_expressions(EXPRsTl,LocalState,InState,ValTl,WF).
3123
3124		% a variation of above that delays computing the expressions until Waitflag 1/2 is set
3125		b_compute_assign_expressions_when(EXPRsTl,LocalState,InState,ValTl,WF,OR) :-
3126		get_assign_expr_priority_wf(OR,WF,LWF),
3127	?	b_compute_expressions_when2(EXPRsTl,LocalState,InState,ValTl,WF,LWF).
3128		b_compute_expressions_when2([], _, _, [],_WF,_).
3129		b_compute_expressions_when2([EXPRsHd|EXPRsTl],LocalState,InState,[ValHd|ValTl],WF,LWF) :-
3130	?	b_compute_expression_when2(EXPRsHd,LocalState,InState,ValHd,WF,LWF),
3131		b_compute_expressions_when2(EXPRsTl,LocalState,InState,ValTl,WF,LWF).
3132
3133		% TO DO: add step number in OR
3134		get_assign_expr_priority_wf(output_required,_WF,LWF) :- !,
3135		% the Output of the statement is required; do not delay computing it
3136		LWF=0. % this would delay computation until WF0 is set: get_wait_flag0(WF,LWF); cf. initialisation for test 2104
3137		get_assign_expr_priority_wf(_,WF,LWF) :-
3138		% the Output is not directly required; compute it later (when we are sure that the statement actually succeeds)
3139		(preferences:preference(use_smt_mode,true)
3140		-> Prio = 2.0 % SMT Mode: we are probably doing CBC checking, we may have set up constraints on ValTl
3141		; Prio=4000), % unless the expression is inside an sequential composition: nothing can depend on ValTl; TO DO: check if we are inside a sequential composition; if not use inf priority; otherwise use 2.0 or 4
3142		get_wait_flag(Prio,get_assign_expr_priority_wf,WF,LWF).
3143
3144		:- block b_compute_expression_when2(?,?,?,?,?,-).
3145		b_compute_expression_when2(eval_must_not_fail(ErrMsg,EXPRsHd),LocalState,InState,Res,WF,_) :- !,
3146		% catch failure; in case the interpreter fails to catch wd-error itself (e.g., try_find_abort is false)
3147		if(b_compute_expression(EXPRsHd,LocalState,InState,ValHd,WF),equal_object_wf(ValHd,Res,WF),
3148		(translate:translate_bexpression_with_limit(EXPRsHd,TS),
3149		add_wd_error_span(ErrMsg,TS,span_predicate(EXPRsHd,LocalState,InState),WF))).
3150		b_compute_expression_when2(EXPRsHd,LocalState,InState,ValHd,WF,_) :-
3151		copy_wf_start(WF,b_compute_expression_when2,CWF), % not sure this is useful for expressions:
3152	?	b_compute_expression(EXPRsHd,LocalState,InState,ValHd,CWF),
3153	?	copy_wf_finish(WF,CWF).
3154
3155
3156		/* -----------------------------*/
3157		/* b_execute_statement */
3158		/* -----------------------------*/
3159		/* b_execute_statement(XMLStatements:input, StateofLocalVariables:input,
3160		StateOfGlobalVariables:input,
3161		ListOfUpdateBindingsForGlobalVariablesAndResultVariables:output) */
3162
3163		:- assert_pre(b_interpreter:b_execute_statement(Stmt,LS,IS,_OS,_WF,_Path,_OR),
3164		(bsyntaxtree:check_if_typed_substitution(Stmt),type_check(LS,store),type_check(IS,store) )).
3165		:- assert_post(b_interpreter:b_execute_statement(_Stmt,_LS,_IS,OS,_WF,_Path,_OR),
3166		(type_check(OS,store))).
3167
3168		b_execute_inner_statement(Body,LocalState,InState,OutState,WF,Path,output_required) :-
3169		get_texpr_expr(Body,BE),
3170		BE \= while(_COND,_STMT,_INV,_VARIANT), % also other non-det substitutions ??
3171		BE \= select(_),
3172		BE \= select(_,_),
3173		BE \= if(_), % case(_,_,_) statements are now translated to if-then-else in ast_cleanup
3174		!,
3175		get_wait_flag0(WF,WF0),
3176		block_execute_statement(WF0,Body,LocalState,InState,OutState,WF,Path).
3177		b_execute_inner_statement(Body,LocalState,InState,OutState,WF,Path,OR) :-
3178		get_wait_flag(2,inner_stmt,WF,LWF), % was 2.0
3179		clone_wait_flags_from1(WF,GroundUponFinish,InnerWF), % copy everything but WF0
3180		b_execute_inner_statement(Body,LocalState,InState,OutState,GroundUponFinish,InnerWF,Path,LWF,OR).
3181
3182		:- block block_execute_statement(-, ?,?,?, ?,?,?).
3183		block_execute_statement(_,Body,LocalState,InState,OutState,WF,Path) :-
3184	?	b_execute_statement(Body,LocalState,InState,OutState,WF,Path,output_required).
3185
3186		:- block b_execute_inner_statement(?,?,?,?,?,?,?,-,?).
3187		b_execute_inner_statement(Body,LocalState,InState,OutState,GUF,InnerWF,Path,_,OR) :-
3188	?	b_execute_statement(Body,LocalState,InState,OutState,InnerWF,Path,OR),
3189		(GUF=ground_upon_finish -> ground_wait_flags(InnerWF) ; ground_wait_flag0(InnerWF)).
3190
3191		:- use_module(source_profiler,[opt_add_source_location_hits/2]).
3192		:- use_module(b_operation_guards,[get_substitution_enabling_condition/4]).
3193
3194
3195		b_execute_statement_nowf(Subst,LS,S,OutS,Ctxt) :-
3196		init_wait_flags_with_call_stack(WF,[prob_command_context(Ctxt,unknown)]),
3197		b_interpreter:b_execute_statement(Subst,LS,S,OutS,WF,_Path),
3198		ground_wait_flags(WF).
3199
3200		b_execute_statement(Stmt, LS, S, OS, WF,Path) :-
3201	?	b_execute_statement(Stmt, LS, S, OS, WF,Path,output_not_required).
3202		b_execute_statement(b(Stmt,_,Infos), LS, S, OS, WF,Path,OR) :- !,
3203	?	b_execute_statement2(Stmt, Infos, LS, S, OS, WF,Path,OR).
3204		b_execute_statement(Stmt, LS, S, OS, WF,Path,OR) :-
3205		add_internal_error('Statement not properly wrapped: ',b_execute_statement(Stmt, LS, S, OS, WF,Path,OR)),
3206		b_execute_statement2(Stmt, [], LS, S, OS, WF,Path,OR).
3207
3208		% blocks should be removed by type-checker
3209		b_execute_statement2(block(Stmt),_,LS,IS,OS,WF,Path,OR) :- !,
3210		b_execute_statement(Stmt,LS,IS,OS,WF,Path,OR). %% NOT COVERED
3211		b_execute_statement2(assign(LHS,Exprs),Info,LocalState,InState,OutState,WF,assign,OR) :- !,
3212		/* Var1, ..., VarN := Expr1, ..., ExprN */
3213		/* also: Var1, fun1(arg), ... := Expr1, Expr2, ... */
3214		opt_add_source_location_hits(Info,1),
3215	?	b_compute_assign_expressions_when(Exprs,LocalState,InState,VALs,WF,OR),% VALs - a list of computed values
3216	?	b_assign_values_or_functions(LHS,VALs,LocalState,InState,OutState,WF,OR).
3217		b_execute_statement2(assign_single_id(IDE,Expr),Info,LocalState,InState,OutState,WF,assign,_OR) :-
3218		get_texpr_id(IDE,ID),!,
3219		opt_add_source_location_hits(Info,1),
3220	?	b_compute_expression(Expr,LocalState,InState,Value,WF), % b_compute_assign_expressions_when
3221		%b_compute_assign_expressions_when([Expr],LocalState,InState,[Value],WF),
3222		OutState=[bind(ID,Value)].
3223		b_execute_statement2(choice(ChoiceList),_,LocalState,InState,OutState,WF,Path,OR) :- !,
3224		/* CHOICE LHS OR RHS OR ... END */
3225		get_wait_flag(2,choice,WF,WFC), % % was 2.0, maybe use length of ChoiceList as Priority ??
3226		b_execute_choice(ChoiceList,LocalState,InState,OutState,WF,Path,WFC,OR).
3227		b_execute_statement2(becomes_element_of(LHS,RHS), /* LHS :: RHS */
3228		Info,LocalState,InState,OutState,WF,becomes_element_of,_OR) :- !,
3229		% LHS must be of the form Var1,..,Vark where all variables are disjoint
3230		opt_add_source_location_hits(Info,1),
3231		b_compute_expression(RHS,LocalState,InState,ValueSet,WF),
3232		check_element_of_wf(SingleValue,ValueSet,WF),
3233		ground_det_wait_flag(WF), %% TODO: remove this
3234		convert_pairs_into_list(LHS,SingleValue,ValList),
3235		set_up_typed_localstate(LHS,ValList,TypedVals,[],OutState,positive),
3236		b_tighter_enumerate_all_values(TypedVals,WF).
3237		b_execute_statement2(becomes_such(Vars,Condition), /* Vars : Condition */
3238		Info,LocalState,InState,OutState,WF,becomes_such,_OR) :- !,
3239		opt_add_source_location_hits(Info,1),
3240	?	b_execute_becomes_such(Vars,Condition,LocalState,InState,OutState,_,WF).
3241		b_execute_statement2(sequence(Seq), /* LHS ; RHS */
3242		_,LocalState,InState,OutUpdates,WF,Path,OR) :- !, %pe_print(sequence(Seq,InState)),
3243	?	b_execute_sequence(Seq,LocalState,InState,OutUpdates,WF,Path,OR).
3244		b_execute_statement2(precondition(PreCond,Body),_,LocalState,InState,OutState,WF,Path,OR) :- !,
3245		%print('*** Non-outermost PRE construct'),nl,
3246		Path=pre(PreRes,IPath),
3247		b_try_check_boolean_expression(PreCond,LocalState,InState,WF,PreRes),
3248		%used to be: ground_det_wait_flag(WF),
3249		check_precondition_result(PreRes,PreCond,LocalState,InState,WF),
3250	?	(PreRes == pred_true -> b_execute_statement(Body,LocalState,InState,OutState,WF,IPath,OR)
3251		; PreRes == pred_false -> IPath = not_executed
3252		; b_execute_inner_statement(Body,LocalState,InState,OutState,WF,IPath,OR) % with extra waitflag
3253		).
3254		b_execute_statement2(assertion(PreCond,Body),_,LocalState,InState,OutState,WF,Path,OR) :- !,
3255	?	b_execute_assertion(PreCond,Body,LocalState,InState,OutState,WF,Path,OR).
3256		b_execute_statement2(witness_then(PreCond,Body),_,LocalState,InState,OutState,WF,Path,OR) :- !,
3257		b_test_boolean_expression(PreCond,LocalState,InState,WF),
3258		b_execute_inner_statement(Body,LocalState,InState,OutState,WF,Path,OR).
3259		b_execute_statement2(select(Whens),_, LocalState, InState, OutState,WF,select(Nr,Path),OR) :- !,
3260		get_texpr_expr(TExpr,select_when(PreCond, Body)), % info field not used for select_when
3261	?	optimized_nth1(Nr, Whens, TExpr), % THIS IS A CHOICE POINT if length(Whens)>1 ! <-------- TO DO guard
3262	?	b_test_boolean_expression(PreCond,LocalState,InState,WF),
3263		%used to call: ground_det_wait_flag(WF), now execute inner statement delays
3264		b_execute_inner_statement(Body,LocalState,InState,OutState,WF,Path,OR).
3265		b_execute_statement2(select(Whens,Else), Infos, LocalState, InState, OutState,WF,Path,OR) :- !,
3266		(
3267	?	b_execute_statement2(select(Whens), Infos, LocalState, InState, OutState,WF,Path,OR)
3268		; % THIS IS A CHOICE POINT ! <-------- TO DO guard
3269		findall(PC,
3270		(member(SW,Whens),get_texpr_expr(SW,select_when(PC,_))), AllPreconds),
3271		b_not_test_list_of_boolean_expression(AllPreconds,LocalState,InState,WF),
3272		Path = select(else,IPath),
3273		b_execute_inner_statement(Else,LocalState,InState,OutState,WF,IPath,OR)
3274		).
3275		b_execute_statement2(var(Parameters,Body), /* VAR _ IN _ substitution */
3276		_,LocalState,InState,NewOutState,WF,var(Path),OR) :- !,
3277		/* introduces a new variable that can be assigned to */
3278		split_names_and_types(Parameters,Names,_),
3279		delete_variables_from_state(Names,InState,InState1), % in case any local parameter name is also a constant/variable: remove it % but if we do an operation_call: we leave context and it becomes visible again !!
3280		% otherwise we may think there are two updates, e.g., in WHILE loop; see Rule_DB_SIGAREA_0030 from test 1303
3281		set_up_undefined_localstate(Parameters,InState1,NewInState),
3282		delete_variables_from_state(Names,LocalState,NewLocalState),
3283		%check_valid_store(InState,var_in_state), check_valid_store(LocalState,var_local_state),
3284	?	b_execute_statement(Body,NewLocalState,NewInState,OutState,WF,Path,OR),
3285		% check_valid_store(OutState,var_out_state),
3286		filter_results(Parameters,OutState,NewOutState,WF)
3287		.
3288		/* it can be ok not to assign to a local variable */
3289
3290		%TODO(DP, 5.8.2008):
3291		b_execute_statement2(let(Parameters,Defs,Body), /* LET _ BE _ IN _ */
3292		_,LocalState,InState,OutState,WF,let(Path),OR) :- !,
3293	?	set_up_typed_localstate(Parameters,LocalState,NewLocalState),
3294		b_execute_let_definitions(Defs,NewLocalState,InState,WF),
3295	?	b_execute_statement(Body,NewLocalState,InState,OutState,WF,Path,OR).
3296		b_execute_statement2(lazy_let_subst(Id,IdExpr,Body),_,LocalState,InState,OutState,WF,lazy_let(Path),OR) :-
3297		!,
3298		add_lazy_let_id_and_expression(Id,IdExpr,LocalState,InState,NewLocalState,WF),
3299		b_execute_statement(Body,NewLocalState,InState,OutState,WF,Path,OR).
3300		b_execute_statement2(any(Parameters,PreCond,Body), /* ANY _ WHERE */
3301		Info,LocalState,InState,OutState,WF0,any(Bindings,Path),OR) :- !, %statistics(runtime,_),
3302		%print('ANY: '), print_bexpr(PreCond),nl, %%
3303	?	set_up_typed_localstate(Parameters,FreshVars,TypedVals,LocalState,NewLocalState,positive),
3304		create_any_bindings(Parameters,FreshVars,Bindings),
3305		push_wait_flag_call_stack_info(WF0,quantifier_call('ANY',Parameters,FreshVars,Info),WF),
3306	?	b_test_inner_boolean_expression(PreCond,NewLocalState,InState,WF), /* check WHERE */
3307		%%observe_state(TypedVals,WF,0), b_tracetest_boolean_expression(PreCond,NewLocalState,InState,WF,one), %% comment in for debugging
3308		b_tighter_enumerate_all_values(TypedVals,WF), % moved enumeration after test; in case WF already instantiated
3309		%TODO: check if we can use b_tighter_enumerate_values_in_ctxt
3310	?	b_execute_statement(Body,NewLocalState,InState,OutState,WF,Path,OR). /* should we use b_execute_inner_statement/LWF here ?? */
3311		b_execute_statement2(skip, /* SKIP */
3312		Info,_LocalState,_InState,OutState,_WF,skip,_OR) :- !,
3313		opt_add_source_location_hits(Info,1),
3314		OutState = [].
3315		b_execute_statement2(parallel(Statements), /* LHS || RHS */ %@@@
3316		_,LocalState,InState,OutState,WF,parallel(Paths),OR) :- !,
3317	?	b_execute_statements_in_parallel(Statements,LocalState,InState,OutState,WF,Paths,OR).
3318		b_execute_statement2(init_statement(Stmt),_,LocalState,InState,OutState,WF,Path,OR) :- !,
3319		/* Like block: but
3320		writes error messages if statement fails */ %@@@
3321		(preferences:get_preference(provide_trace_information,true)
3322		-> nl,print(' =INIT=> '),translate:print_subst(Stmt),nl, flush_output(user_output),
3323		statistics(walltime,[Tot1,_])
3324		; true),
3325	?	if(b_execute_initialisation_statement(Stmt,LocalState,InState,OutState,WF,Path,OR),
3326		(
3327		(preferences:get_preference(provide_trace_information,true)
3328		-> statistics(walltime,[Tot2,_]), Tot is Tot2-Tot1,
3329		format(' [=OK= ~w ms]~n',[Tot]), flush_output(user_output)
3330		; true)
3331		),
3332		( translate:translate_substitution(Stmt,TStmtStr),
3333		(bmachine:b_machine_temp_predicate(_TempPred)
3334		-> Msg = 'INITIALISATION statement cannot be executed with extra predicate: ',
3335		add_error_wf(initialisation_fails,Msg,TStmtStr,Stmt,WF)
3336		% do not add as state error; user requested transition
3337		; Msg = 'INITIALISATION statement fails: ',
3338		(get_substitution_enabling_condition(Stmt,SpanPred,_BSVars,_IsPreciseV)
3339		-> %insert_custom_predicate_into_guard(EnablingCondition,TempPred,SpanPred),
3340		ErrPos = span_predicate(SpanPred,LocalState,InState) % for visualising by user
3341		% Note: user can also visualise by chooise execute by predicate (in TK)
3342		; ErrPos = Stmt
3343		),
3344		% add as state error so that we can visualise span predicate
3345		add_state_error_wf(initialisation_fails,Msg,TStmtStr,ErrPos,WF) % cf test 1736 and 278
3346		%add_error_wf(initialisation_fails,Msg,TStmtStr,ErrPos,WF)
3347		),
3348		fail
3349		)
3350		).
3351		b_execute_statement2(if(IfList),_,LocalState,InState,OutState,WF,if,OR) :- !,
3352		%LWF=1,
3353		LWF='$GENERATE_ON_DEMAND', %
3354	?	b_execute_else_list(IfList,LocalState,InState,OutState,WF,LWF,OR).
3355		b_execute_statement2(operation_call(Operation,Results,Parameters),Info,LocalState,InState,OutState,WF,
3356		operation_call(OperationName,ParamValues,ResultValues,InnerPath),OR) :- !,
3357		def_get_texpr_id(Operation,op(OperationName)),
3358	?	b_execute_operation_with_parameters(OperationName,LocalState,InState,Results,
3359		Parameters,OpOutState,ParamValues,ResultValues,InnerPath,Info,WF,OR),
3360		split_names_and_types(Results,ResultingIDs,_),
3361		store_values(ResultingIDs, ResultValues, ResultsOutState),
3362		combine_updates(ResultsOutState,OpOutState,OutState).
3363
3364		b_execute_statement2(while(COND,STMT,INV,VARIANT),
3365		Info,LocalState,InState,OutState,WF0,while,_OR) :- !,
3366		%hit_profiler:add_profile_hit(while(COND,WF),2),
3367		% we may go around the loop many times: avoid carrying around unused variables
3368		get_while_reads_write_info_and_filter_state(Info,LocalState,InState,LS,IS,ModVars),
3369		push_wait_flag_call_stack_info(WF0,b_operator_call('WHILE',[],Info),WF), % TODO: provide subst. call stack entry
3370		%print_message(execute_while(LocalState,InState)),
3371		b_compiler:b_optimize(INV,ModVars,LS,IS,CINV,WF),
3372		b_compiler:b_optimize(COND,ModVars,LS,IS,CCOND,WF),
3373		b_compiler:b_optimize(VARIANT,ModVars,LS,IS,CVARIANT,WF),
3374		%,b_compiler:b_compile(STMT,ModVars,LS,IS,CSTMT,WF)
3375		% TO DO: maybe exclude in one go; use ordered approach ?
3376		%exclude(unused_variable(ModVars),LS,LS2), % only keep modified vars; all other compiled
3377		%exclude(unused_variable(ModVars),IS,IS2), % only keep modified vars; all other compiled
3378		b_compute_expression(CVARIANT,LS,IS,VarVal,WF),
3379		b_execute_while(CCOND,STMT,CINV,CVARIANT,ModVars,VarVal,LS,IS,OutState,WF).
3380		b_execute_statement2(external_subst_call(FunName,Args),Info,LocalState,State,OutState,WF,external(FunName),_OR) :-
3381		!, b_compute_expressions(Args, LocalState,State, EvaluatedArgs, WF),
3382		push_wait_flag_call_stack_info(WF,external_call(FunName,EvaluatedArgs,Info),WF2),
3383		call_external_substitution(FunName,EvaluatedArgs,State,OutState,Info,WF2).
3384		b_execute_statement2(E,I,LS,S,O,WF,Path,OR) :-
3385		add_internal_error('Uncovered statement: ',b_execute_statement2(E,I,LS,S,O,WF,Path,OR)),
3386		print_functor(E),nl,fail.
3387
3388		% -------------------
3389
3390		b_execute_becomes_such(Vars,Condition,LocalState,InState,OutState,Values,WF) :- !,
3391		% create the LHS variables in the local state
3392	?	set_up_typed_localstate(Vars,Values,TypedVals,LocalState,TempLocalState1,positive),
3393		get_texpr_ids(Vars,Ids),
3394		% store those values also the outgoing state
3395		store_values(Ids,Values,OutState),
3396		% there might be some variables of the form x$0 to access the
3397		% values before the substitution. We put them into the local state
3398		insert_before_substitution_variables(Vars,LocalState,InState,TempLocalState1,TempLocalState),
3399	?	b_test_inner_boolean_expression(Condition,TempLocalState,InState,WF),
3400		b_tighter_enumerate_values_in_ctxt(TypedVals,Condition,WF). % moved enumeration after test, to avoid overhead in case Condition is deterministic (see e.g. WhileAssignTupleChoose_v2)
3401
3402
3403		b_execute_sequence([],_LocalState,_InState,[],_WF,[],_OR).
3404		b_execute_sequence([First|Rest],LocalState,InState,OutUpdates,WF,Path,OR) :-
3405		(Rest == []
3406	?	-> b_execute_statement(First,LocalState,InState,OutUpdates,WF,Path,OR)
3407		; Path = sequence(Path1,RestPath),
3408	?	b_execute_statement(First,LocalState,InState,LHSUpdates,WF,Path1,output_required),
3409	?	ground_det_wait_flag(WF), % maybe better to delay next execute_statement ? TODO
3410		store_intermediate_updates_wf(InState,LHSUpdates,IntermediateState,First,WF),
3411		% TO DO: statically determine what the Rest can modify and copy over LHSUpdates not modified by Rest into OutUpdates
3412	?	b_execute_statement_list_when_state_set(Rest,LocalState,IntermediateState,
3413		LHSUpdates,OutUpdates,WF,RestPath,OR)
3414		).
3415
3416
3417		:- block check_precondition_result(-,?,?,?,?).
3418		check_precondition_result(pred_true,_,_,_,_).
3419		check_precondition_result(pred_false,PreCond,LS,S,WF) :-
3420		translate_bexpression(PreCond,PreString),
3421		add_abort_error_span(precondition_error,'Precondition violated: ',PreString,span_predicate(PreCond,LS,S),WF).
3422
3423		create_any_bindings([],[],[]).
3424		create_any_bindings([Param|Prest],[Value|Vrest],[bind(Id,Value)|Brest]) :-
3425		get_texpr_id(Param,Id),
3426		create_any_bindings(Prest,Vrest,Brest).
3427
3428		% insert the values of variables before the substitution under an
3429		% alternative name. The alternative name is given as an optional extra
3430		% information in the variable (see type-checking of becomes_such for
3431		% details). Usually (i.e. always) the alternative name is x$0 for the variable x.
3432		insert_before_substitution_variables([],_LocalState,_InState,State,State).
3433		insert_before_substitution_variables([Var|VRest],LocalState,InState,StateA,ResultStateB) :-
3434		get_texpr_info(Var,Infos),
3435	?	( member(before_substitution(_,Alternative),Infos) ->
3436		def_get_texpr_id(Var,Id),
3437		lookup_value_for_existing_id(Id,LocalState,InState,Value),
3438		store_value(Alternative,Value,StateA,StateC)
3439		;
3440		StateA = StateC),
3441		insert_before_substitution_variables(VRest,LocalState,InState,StateC,ResultStateB).
3442
3443
3444
3445		% treat the bool(.) operator
3446		b_convert_bool(Pred,LocalState,State,WF,PredRes) :-
3447		get_wait_flag0(WF,WF0), % first give a chance for PredRes to be instantiated
3448	?	b_convert_bool_wf0(Pred,LocalState,State,WF,PredRes,WF0).
3449
3450		:- block b_convert_bool_wf0(?,?,?,?,-,-).
3451		b_convert_bool_wf0(Pred,LocalState,State,WF,PredRes,_) :- PredRes==pred_true,!,
3452		%% print('bool(.)=TRUE '), translate:print_bexpr(Pred),nl, %%
3453		b_test_inner_boolean_expression(Pred,LocalState,State,WF).
3454		b_convert_bool_wf0(Pred,LocalState,State,WF,PredRes,_) :- PredRes==pred_false,!,
3455		%% print('bool(.)=FALSE '), translate:print_bexpr(Pred),nl, %%
3456		b_not_test_inner_boolean_expression(Pred,LocalState,State,WF).
3457		b_convert_bool_wf0(Pred,LocalState,State,WF,PredRes,_) :-
3458		%% print('bool(.) check : '), translate:print_bexpr(Pred),nl, % obsv(LocalState),
3459	?	b_try_check_boolean_expression_wf(Pred,LocalState,State,WF,PredRes ).
3460		%% print('finished bool(.) check : '), translate:print_bexpr(Pred),nl,translate:print_bstate(LocalState),nl.
3461
3462		% Additional time limit +TO in ms, e.g., used for CDCL(T). +TORes is time_out if a timeout occurred.
3463		b_convert_bool_timeout(Pred,LocalState,State,WF,PredRes,TO,TORes) :-
3464		get_wait_flag0(WF,WF0),
3465		b_convert_bool_wf0_timeout(Pred,LocalState,State,WF,PredRes,WF0,TO,TORes).
3466
3467		:- block b_convert_bool_wf0_timeout(?,?,?,?,-,-,?,?).
3468		b_convert_bool_wf0_timeout(Pred,LocalState,State,WF,PredRes,_,TO,TORes) :-
3469		PredRes == pred_true,
3470		!,
3471		safe_time_out(b_test_inner_boolean_expression(Pred,LocalState,State,WF),
3472		TO,
3473		TORes).
3474		b_convert_bool_wf0_timeout(Pred,LocalState,State,WF,PredRes,_,TO,TORes) :-
3475		PredRes == pred_false,
3476		!,
3477		safe_time_out(b_not_test_inner_boolean_expression(Pred,LocalState,State,WF),
3478		TO,
3479		TORes).
3480		b_convert_bool_wf0_timeout(Pred,LocalState,State,WF,PredRes,_,TO,TORes) :-
3481		safe_time_out(b_try_check_boolean_expression_wf(Pred,LocalState,State,WF,PredRes ),
3482		TO,
3483		TORes).
3484
3485		%%obsv([]).
3486		%%obsv([bind(Var,Val) | T] ) :- when(ground(Val), format("~w = ~w~n",[Var,Val])), obsv(T).
3487
3488		% check boolean expression without enumeration predicate result (unless WFE is set)
3489		b_try_check_boolean_expression_no_enum_wf(Pred,LocalState,State,WF,PredRes) :-
3490	?	b_try_check_boolean_expression_lwf(Pred,LocalState,State,WF,'$NO_ENUMERATION',PredRes,_).
3491
3492		b_try_check_boolean_expression_wf(Pred,LocalState,State,WF,PredRes) :-
3493	?	b_try_check_boolean_expression_lwf(Pred,LocalState,State,WF,'$ENUMERATION',PredRes,'$GENERATE_ON_DEMAND' ).
3494		% try to do check_boolean expression; if not possible create choice point if LWF is grounded
3495		b_try_check_boolean_expression_lwf(Pred,LocalState,InState,WF,DoEnumeration,PredRes,LWF) :-
3496	?	b_compiler:b_optimize(Pred,[],LocalState,InState,CPRED,WF), % this increases chance that check can be applied+avoids multiple computations in two branches
3497		% still: some computations may not be pre-computed, e.g., union of closures, ..., see Rule_DB_PSR_0003_C
3498	?	b_try_check_boolean_expression_lwf_c(CPRED,LocalState,InState,WF,DoEnumeration,PredRes,LWF).
3499
3500		b_try_check_boolean_expression_lwf_c(b(truth,_,_),_LocalState,_InState,_WF,_,PredRes,_LWF) :- !,
3501		% typical case in e.g. IF-THEN-ELSE
3502		PredRes= pred_true.
3503		b_try_check_boolean_expression_lwf_c(Pred,LocalState,InState,WF,DoEnumeration,PredRes,LWF) :-
3504		copy_wf_start(WF,try_check,CWF),
3505	?	if(b_check_boolean_expression_with_enum(Pred,LocalState,InState,CWF,DoEnumeration,Res),
3506		% Note: we do not use a cut here ! usually b_check will not enumerate; but on rare occasions it can (apply function in inverse,...)
3507		(PredRes=Res,
3508	?	copy_wf_finish(WF,CWF)
3509		),
3510		b_try_check_failed(Pred,LocalState,InState,WF,DoEnumeration,PredRes,LWF)
3511		).
3512		b_try_check_failed(Pred,LocalState,InState,WF,DoEnumeration,PredRes,LWF) :-
3513		% print(choice_point(LWF)),nl, translate:print_bexpr(Pred),nl,
3514		perfmessagecall(choice_point,reification_of_check_predicate_failed,translate:print_bexpr(Pred),Pred),
3515		(LWF=='$GENERATE_ON_DEMAND' -> get_binary_choice_wait_flag('$GENERATE_ON_DEMAND',WF,WF1)
3516		; var(LWF),DoEnumeration=='$NO_ENUMERATION' -> get_enumeration_finished_wait_flag(WF,WF1) % nothing will enum LWF
3517		; WF1=LWF),
3518		b_try_check_boolean_expression_lwf_block(Pred,LocalState,InState,WF,PredRes,WF1).
3519
3520		% a version of b_check_boolean_expression which will enumerate its result as last resort
3521		% should we only do this in SMT mode : preferences:preference(use_smt_mode,true) ?
3522		b_check_boolean_expression_with_enum(Pred,LocalState,State,WF,DoEnumeration,Res) :-
3523	?	b_check_boolean_expression(Pred,LocalState,State,WF,Res),
3524		(nonvar(Res) -> true
3525		; DoEnumeration=='$NO_ENUMERATION' -> get_enumeration_finished_wait_flag(WF,EWF), enum_pred_result(Res,EWF,WF)
3526		; get_wait_flag0(WF,LWF0),
3527		enum_pred_result0(Res,LWF0,WF)).
3528
3529		% first set up with wait_flag0: easy to get, avoid putting unnecessary waitflags into store
3530		% relevant for DataValidationTest.mch with n>20000
3531		:- block enum_pred_result0(-,-,?).
3532		enum_pred_result0(Res,_,WF) :- var(Res),!,
3533		get_last_wait_flag(b_check_boolean_expression_with_enum,WF,LWF),
3534		enum_pred_result(Res,LWF,WF). % before doing infinite enumerations: better do case-distinction here
3535		enum_pred_result0(_,_,_).
3536
3537		:- block enum_pred_result(-,-,?).
3538		enum_pred_result(pred_true,_,_).
3539		enum_pred_result(pred_false,_,_).
3540
3541		:- block b_try_check_boolean_expression_lwf_block(?,?,?, ?,-,-).
3542		b_try_check_boolean_expression_lwf_block(Pred,LocalState,InState,WF,PREDRES,_) :-
3543		PREDRES \== pred_false,
3544		% print(' TRUE +++++> '), translate:print_bexpr(Pred),nl,
3545	?	b_test_inner_boolean_expression(Pred,LocalState,InState,WF),
3546		PREDRES = pred_true. % set it only after we have actually checked the predicate; e.g., for IF we may execute rest of while loop etc... before actually having set up the constraint Pred; See Hansen23_WhilePerformance
3547		b_try_check_boolean_expression_lwf_block(Pred,LocalState,InState,WF,PREDRES,_) :-
3548		PREDRES \== pred_true,
3549		% print(' FALSE +++++> '), translate:print_bexpr(Pred),nl,
3550	?	b_not_test_inner_boolean_expression(Pred,LocalState,InState,WF),
3551		PREDRES = pred_false.
3552
3553		% try to do check_boolean expression; if not possible create choice point *directly*
3554		b_try_check_boolean_expression(Pred,LocalState,InState,WF,PredRes) :-
3555		b_compiler:b_optimize(Pred,[],LocalState,InState,CPRED,WF), % this increases chance that check can be applied+avoids multiple computations in two branches
3556		b_try_check_boolean_expression_c(CPRED,LocalState,InState,WF,PredRes).
3557		b_try_check_boolean_expression_c(Pred,LocalState,InState,WF,PredRes) :-
3558		copy_wf_start(WF,try_check_c,CWF),
3559		if(b_check_boolean_expression(Pred,LocalState,InState,CWF,Res),
3560		(PredRes=Res,copy_wf_finish(WF,CWF)),
3561	?	b_try_check_boolean_expression_c2(Pred,LocalState,InState,WF,PredRes)
3562		).
3563		b_try_check_boolean_expression_c2(Pred,LocalState,InState,WF,pred_true) :-
3564		%hit_profiler:add_profile_hit(b_try_check_failed(Pred),3),
3565		b_test_inner_boolean_expression(Pred,LocalState,InState,WF).
3566		b_try_check_boolean_expression_c2(Pred,LocalState,InState,WF,pred_false) :-
3567		b_not_test_inner_boolean_expression(Pred,LocalState,InState,WF).
3568
3569
3570		% WHILE SUBSTITUTION TREATMENT:
3571
3572		:- if(environ(prob_noopt_mode,true)).
3573		get_while_reads_write_info_and_filter_state(Info,LocalState,InState,LS,IS,ModVars) :-
3574		member(modifies(ModVars),Info),!,
3575		LS=LocalState, IS=InState. % do not filter state
3576		:- endif.
3577		get_while_reads_write_info_and_filter_state(Info,LocalState,InState,LS,IS,ModVars) :-
3578	?	member(reads(ReadVars),Info),
3579	?	member(modifies(ModVars),Info),!,
3580		% we may go around the loop many times: avoid carrying around unused variables
3581		ord_union(ReadVars,ModVars,ReadOrModVars),
3582		filter_states(ReadOrModVars,LocalState,InState,LS,IS).
3583		get_while_reads_write_info_and_filter_state(Info,LocalState,InState,LS,IS,ModVars) :-
3584		add_internal_error('No reads & modifies info for while loop: ',get_while_reads_write_info_and_filter_state(Info,LocalState,InState,LS,IS,ModVars)),
3585		ModVars=_, % all variables assumed to be modified
3586		LS=LocalState, IS=InState.
3587
3588		unused_variable(List,bind(Var,_)) :-
3589		% b_is_variable(Var), % TO DO: also include constants in reads Info ?
3590		ord_nonmember(Var,List).
3591		unused_localvariable(List,bind(Var,Val)) :- ord_nonmember(Var,List),
3592		(nonvar(Val),Val=(_,_) -> atom_codes(Var,Codes), Codes \= [64|_] % not a lazy_let ID starting with @
3593		% TO DO: either ensure lazy-let ids are also included in reads/writes ! or mark Val not as pair but using a special functor in add_lazy_let_id_to_local_state ?
3594		; true).
3595
3596		filter_states(ReadOrModVars,LocalState,InState,LS,IS) :-
3597		exclude(unused_localvariable(ReadOrModVars),LocalState,LS),
3598		exclude(unused_variable(ReadOrModVars),InState,IS).
3599		% TO DO: investigate whether we should use ord_intersect; ReadVars is already sorted
3600
3601		:- block lazy_exclude(-,?,?).
3602		lazy_exclude([],_,[]).
3603		lazy_exclude([bind(Var,Val)|T],ModVars,Res) :- lazy_exclude_aux(Var,Val,T,ModVars,Res).
3604		:- block lazy_exclude_aux(-,?,?,?,?).
3605		lazy_exclude_aux(Var,Val,T,ModVars,Res) :-
3606	?	(member(Var,ModVars) -> Res = [bind(Var,Val)|RT]
3607		; Res = RT),
3608		lazy_exclude(T,ModVars,RT).
3609
3610
3611		:- use_module(kernel_tools,[ground_state_check/2]).
3612		% outermost while code:; at next iteration b_execute_while1 will be called.
3613		:- block b_execute_while(?,?,?,?,?,-, ?,?,?, ?). % we block on Variant Value int(VarVal)
3614		b_execute_while(COND,STMT,INV,VARIANT,ModVars,int(VarVal),LocalState,InState,OutState,WF) :-
3615		%kernel_waitflags:get_idle_wait_flag(b_execute_while,WF,LWF),
3616		(number(VarVal),VarVal =< 50
3617		-> LWF=VarVal % we will wait anyway on GrInState below; no danger for WD issues in in b_optimize
3618		; no_pending_waitflags(WF) -> get_wait_flag0(WF,LWF) %important for e.g. PerformanceTests/While/LiftExec_LIM.mch
3619		; kernel_waitflags:get_last_wait_flag(b_execute_while1,WF,LWF) % to do: maybe get largest waitflag to avoid as much as possible that new choice points get enumerated before while triggers?
3620		% see also tests 979, 981
3621		),
3622		% before entering while loop, we wait for co-routines to complete that may have activated b_execute_while
3623		b_execute_while_idle(COND,STMT,INV,VARIANT,ModVars,int(VarVal),LocalState,InState,OutState,WF,LWF).
3624
3625		:- block b_execute_while_idle(?,?,?,?,?,?, ?,?,?, ?,-). % we block on enumeration starting wait_flag
3626		b_execute_while_idle(COND,STMT,INV,VARIANT,ModVars,int(VarVal),LocalState,InState,OutState,WF,_) :-
3627		%ground_constraintprop_wait_flags(WF),
3628		(number(VarVal), VarVal>50, preference(compile_while_body,true)
3629		% if VarVal > 50 -> worthwhile to compile STMT
3630		% TO DO: also take size of body into account, and what if only a small part of the body is reachable in each iteration
3631	?	-> b_compiler:b_optimize(STMT,ModVars,LocalState,InState,CSTMT,WF),
3632		% print(compiled_while(ModVars)),nl, translate:print_subst(CSTMT),nl,
3633		OutState=WhileOutState,
3634		exclude(unused_variable(ModVars),LocalState,LS), % only keep modified vars; all other compiled
3635		exclude(unused_variable(ModVars),InState,IS) % only keep modified vars; all other compiled
3636		; CSTMT=STMT, LS=LocalState, IS=InState,
3637		lazy_exclude(WhileOutState,ModVars,OutState) % only copy over those variables (potentially) modified by While loop
3638		% Note: it is important that we only have one copy of each modified variable in OutState
3639		),
3640		ground_state_check(InState,GrInState),
3641	?	b_execute_while_loop_block(GrInState,COND,CSTMT,INV,VARIANT,none,VarVal,LS,IS,WhileOutState,WF).
3642
3643		:- block b_execute_while_loop_block(-,?,?,?,?,?,?,?,?,?,?).
3644		b_execute_while_loop_block(_,COND,CSTMT,INV,VARIANT,none,VarVal,LS,IS,WhileOutState,WF) :-
3645	?	b_execute_while_loop(COND,CSTMT,INV,VARIANT,none,VarVal,LS,IS,WhileOutState,WF).
3646
3647		:- block b_execute_while1(?,?,?,?,?,-,?,?,?,?).
3648		b_execute_while1(COND,STMT,INV,VARIANT,PrevVariantValue,int(VarVal),LocalState,InState,OutState,WF) :-
3649		% get_last_wait_flag(while(VarVal),WF,LWF),
3650		deref_wf(WF,FreshWF),
3651		%ground_constraintprop_wait_flags(FreshWF), % this is not a good idea, co-routine may be triggered while grounding WF; this subsidiary call will prevent grounding from completing and may trigger later waitflags before earlier ones are finished
3652		% this can lead to enumeration warnings; the same applies to other calls to ground_constraintprop_wait_flags below
3653		b_execute_while_loop(COND,STMT,INV,VARIANT,PrevVariantValue,VarVal,LocalState,InState,OutState,FreshWF).
3654
3655		% block on PrevVarVal and VarVal not yet needed here; but we need it for b_execute_while_body below
3656		:- block b_execute_while_loop(?,?,?,?,-,?,?,?,?,?), b_execute_while_loop(?,?,?,?,?,-,?,?,?,?).
3657		b_execute_while_loop(COND,STMT,INV,VARIANT,PrevVarVal,VarVal,LocalState,InState,OutState,WF) :-
3658	?	b_try_check_boolean_expression_c(INV,LocalState,InState,WF,INVRes),
3659		%ground_constraintprop_wait_flags(WF), % seems to slow down interpretation
3660	?	b_check_execute_while_loop1(INVRes,COND,STMT,INV,VARIANT,PrevVarVal,VarVal,LocalState,InState,OutState,WF).
3661
3662		:- block b_check_execute_while_loop1(-,?,?,?,?,?,?,?,?,?,?).
3663		b_check_execute_while_loop1(pred_false,_COND,_STMT,INV,_VAR,_PrevVarVal,VarVal,LocalState,InState,_OutState,WF) :-
3664		add_abort_error_span(while_invariant_violation,
3665		'While INVARIANT VIOLATED, current VARIANT value: ',VarVal,span_predicate(INV,LocalState,InState),WF).
3666		b_check_execute_while_loop1(pred_true,COND,STMT,INV,VARIANT,PrevVarVal,VarVal,LocalState,InState,OutState,WF) :-
3667		b_try_check_boolean_expression_c(COND,LocalState,InState,WF,CondRes),
3668		%ground_constraintprop_wait_flags(WF), % seems to slow down interpretation
3669	?	b_check_execute_while_loop2(CondRes,COND,STMT,INV,VARIANT,PrevVarVal,VarVal,LocalState,InState,OutState,WF).
3670
3671		:- block b_check_execute_while_loop2(-,?,?,?,?,?,?,?,?,?,?).
3672		b_check_execute_while_loop2(pred_false,_COND,_STMT,_INV,_VARIANT,_PrevVarVal,_VarVal,_LS,InState,OutState,_WF) :-
3673		OutState=InState. % we copy over the while InState: the updates will be computed at the end of the while loop
3674		b_check_execute_while_loop2(pred_true,COND,STMT,INV,VARIANT,PrevVarVal,VarVal,LocalState,InState,OutState,WF) :-
3675
3676		%hit_profiler:add_profile_hit(b_execute_while_body(STMT,VarVal,PrevVarVal,LocalState),2),
3677		% TO DO: maybe only compute VARIANT now and not above ??
3678		% b_compute_expression(VARIANT,LocalState,InState,VarVal,WF),
3679		% ground_constraintprop_wait_flags(WF), %% moved here because VARIANT computed later
3680	?	b_execute_while_body(COND,STMT,INV,VARIANT,PrevVarVal,VarVal,LocalState,InState,OutState,WF).
3681
3682		%:- block b_execute_while_body(?,?,?,?,-,?,?,?,?,?), b_execute_while_body(?,?,?,?,?,-,?,?,?,?).
3683		% we must ensure VarVal and PrevVaraintValue known
3684		% the block declaration above for b_execute_while_loop already ensures this
3685		b_execute_while_body(_COND,_STMT,_INVARIANT,VAR,_PV,VarVal,LocalState,InState,_OutState,WF) :-
3686		VarVal<0, !, % more efficient than is_not_natural(int(VarVal)),
3687		%ground_constraintprop_wait_flags(WF),
3688		% add_abort_error_span will fail; hence no need to set _OutState
3689		add_abort_error_span(while_variant_error,'While VARIANT not NATURAL:',VarVal,span_predicate(VAR,LocalState,InState),WF).
3690		b_execute_while_body(_COND,_STMT,_INVARIANT,VAR,PrevVariantValue,VarVal,LocalState,InState,_OutState,WF) :-
3691		% check no longer required VarVal>=0,%is_natural(int(VarVal),WF),
3692		PrevVariantValue \= none,
3693		PrevVariantValue =< VarVal, !, %less_than_equal(int(PrevVariantValue),int(VarVal)),
3694		%ground_constraintprop_wait_flags(WF),
3695		% add_abort_error_span will fail; hence no need to set _OutState
3696		ajoin(['VARIANT = ',VarVal,', previous value = ',PrevVariantValue],Details),
3697		add_abort_error_span(while_variant_error,'While VARIANT not decreasing:',
3698		Details,span_predicate(VAR,LocalState,InState),WF).
3699		b_execute_while_body(COND,STMT,INV,VARIANT,_PrevVariantValue,VarVal,LocalState,InState,OutState,WF) :-
3700		% check no longer required due to cuts above %VarVal>=0, %is_natural(int(VarVal),WF),
3701		%(PrevVariantValue==none -> true ; less_than(int(VarVal),int(PrevVariantValue))),
3702		%ground_constraintprop_wait_flags(WF), % seems to slow down interpretation
3703		copy_wf_start(WF,while_body,CWF),
3704	?	b_execute_statement(STMT,LocalState,InState,LHSUpdates,CWF,_Path1,output_required),
3705		copy_wf_finish(WF,CWF),
3706		ground_det_wait_flag(WF), % TODO: remove this
3707		store_intermediate_updates_wf(InState,LHSUpdates,IntermediateState,STMT,WF),
3708		check_state_skeleton_bound(LHSUpdates,Bound), % otherwise variable lookups will cause problems; ensures IntermediateState skeleton bound
3709		b_execute_while_when_state_set(COND,STMT,INV,VARIANT,VarVal,LocalState,IntermediateState,OutState,WF,Bound).
3710
3711		:- block b_execute_while_when_state_set(?,?,?,?,?,?,?,?,?,-).
3712		b_execute_while_when_state_set(COND,STMT,INV,VARIANT,PrevVariantValue,LocalState,State,Res,WF,_) :-
3713		copy_wf_start(WF,while2,CWF),
3714		b_compute_expression(VARIANT,LocalState,State,VarVal,CWF),
3715		copy_wf_finish(WF,CWF),
3716		b_execute_while1(COND,STMT,INV,VARIANT,PrevVariantValue,VarVal,LocalState,State,Res,WF).
3717
3718		% ------------- IF-THEN-ELSE
3719
3720		:- block b_execute_else_list2(-,?,?,?, ?,?,?,-,?). % should we also unblock if LWF set ? needed for seq. composition to set up state ??
3721		b_execute_else_list2(PredRes,Body,Rest,LocalState,InState,OutState,InnerWF,LWF,OR) :-
3722		%(var(PredRes) -> print('IF-THEN-ELSE ENUMERATION: '), translate:print_subst(Body),nl ; true),
3723	?	b_execute_else_list3(PredRes,Body,Rest,LocalState,InState,OutState,InnerWF,LWF,OR).
3724
3725		b_execute_else_list3(pred_true,Body,_,LocalState,InState,OutState,WF,_,OR) :-
3726	?	push_wait_flag_call_stack_info(WF,b_expr_call(if_then_body,Body),WF2),
3727	?	b_execute_statement(Body,LocalState,InState,OutState,WF2,_Path,OR).
3728		b_execute_else_list3(pred_false,_Body,Rest,LocalState,InState,OutState,WF,LWF,OR) :-
3729	?	b_execute_else_list(Rest,LocalState,InState,OutState,WF,LWF,OR).
3730
3731		b_execute_else_list([],_,_State,[],_WF,_LWF,_OR). /* skip */
3732		b_execute_else_list([TExpr|Rest],LocalState,InState,OutState,WF,LWF,OR) :-
3733		get_texpr_expr(TExpr,if_elsif(Test,Body)), % Info field not used
3734		% get_enumeration_finished_wait_flag(WF,LWF),
3735		InnerWF=WF, %clone_wait_flags_from1(WF,InnerWF),
3736		push_wait_flag_call_stack_info(InnerWF,b_expr_call(if_elsif_test,Test),WF2),
3737	?	b_try_check_boolean_expression_lwf(Test,LocalState,InState,WF2,'$ENUMERATION',PredRes,LWF),
3738		%ground_wait_flag0(InnerWF),
3739		(nonvar(PredRes) -> b_execute_else_list3(PredRes,Body,Rest,LocalState,InState,OutState,InnerWF,LWF,OR)
3740		; (LWF == '$GENERATE_ON_DEMAND' ->
3741		get_wait_flag0(WF,LWF1),
3742		get_wait_flag_if_necessary(PredRes,LWF1,OR,WF,LWF2)
3743		; LWF2=LWF),
3744	?	b_execute_else_list2(PredRes,Body,Rest,LocalState,InState,OutState,InnerWF,LWF2,OR)
3745		).
3746
3747		% avoid calling get_wait_flag if possible (expensive)
3748		:- block get_wait_flag_if_necessary(-,-,?,?,?).
3749		get_wait_flag_if_necessary(PredRes,_,OR,WF,LWF2) :- var(PredRes), !, % we need waitflag
3750		(preferences:preference(use_smt_mode,true) -> Prio = 2 % was 2.0
3751		; OR == output_required -> Prio = 2000
3752		; Prio = 200000 %last_finite_priority(Prio)
3753		), % TO DO: check if there is a guard inside; if not we can wait much longer; unless we are in CBC mode
3754		get_wait_flag(Prio,if_else,WF,LWF2).
3755		get_wait_flag_if_necessary(_,_,_,_,_).
3756
3757		:- block b_execute_choice(?,?,?,?,?,?,-,?).
3758		b_execute_choice(ChoiceList,LocalState,InState,OutState,WF,choice(Nr,Path),_WFC,OR) :-
3759	?	nth1(Nr,ChoiceList,Choice),
3760		b_execute_statement(Choice,LocalState,InState,OutState,WF,Path,OR).
3761
3762		% execute ASSERT PreCond THEN Body
3763		b_execute_assertion(_PreCond,Body,LocalState,InState,OutState,WF,Path,OR) :-
3764		preference(do_assert_checking,false), % ASSERT checking disabled
3765		!,
3766		b_execute_statement(Body,LocalState,InState,OutState,WF,Path,OR).
3767		b_execute_assertion(PreCond,Body,LocalState,InState,OutState,WF,Path,OR) :-
3768	?	b_try_check_boolean_expression_lwf(PreCond,LocalState,InState,WF,'$ENUMERATION',PredRes,WFC),
3769		% enumeration of PredRes before WFE set make sense, Body can instantiate values
3770		(var(PredRes) -> get_last_wait_flag(assertion,WF,WFC) ; true),
3771		b_execute_assertion_block(PredRes,PreCond,Body,LocalState,InState,OutState,WF,Path,OR).
3772
3773		:- block b_execute_assertion_block(-, ?,?,?,?, ?,?,?,?).
3774		b_execute_assertion_block(pred_true,_PreCond,Body,LocalState,InState,OutState,WF,Path,OR) :-
3775		Path = assertion(IPath),
3776		b_execute_statement(Body,LocalState,InState,OutState,WF,IPath,OR).
3777		b_execute_assertion_block(pred_false,PreCond,_Body,LocalState,InState,_OutState,WF,Path,_OR) :-
3778		Path = assertion_violated,
3779		translate_bexpression(PreCond,PreString),
3780		add_abort_error_span(assert_error,'ASSERT violated: ',PreString,span_predicate(PreCond,LocalState,InState),WF).
3781
3782		:- block check_state_skeleton_bound(-,?).
3783		check_state_skeleton_bound([],true).
3784		check_state_skeleton_bound([bind(Var,_)|T],Res) :-
3785		check_state_skeleton_bound_aux(Var,T,Res).
3786
3787		:- block check_state_skeleton_bound_aux(-,?,?).
3788		check_state_skeleton_bound_aux(Var,T,Res) :-
3789		(atomic(Var) -> true ; print('*** variable name not atomic: '), print(Var),nl),
3790		check_state_skeleton_bound(T,Res).
3791
3792
3793		b_execute_statement_list_when_state_set(StmtList,LS,State,USoFar,Res,WF,Path,OR) :-
3794		check_state_skeleton_bound(State,Bound), % otherwise variable lookups will cause problems
3795	?	b_execute_statement_when_state_set2(StmtList,LS,State,USoFar,Res,WF,Path,Bound,OR).
3796		:- block b_execute_statement_when_state_set2(?,?,?,?,?,?,?,-,?).
3797		b_execute_statement_when_state_set2(StmtList,LS,State,UpdatesSofar,Res,WF,Path,_,OR) :-
3798		copy_wf_start(WF,while2,CWF),
3799	?	b_execute_sequence(StmtList,LS,State,StmtUpdates,CWF,Path,OR),
3800	?	copy_wf_finish(WF,CWF),
3801	?	merge_updates(UpdatesSofar,StmtUpdates,Res).
3802
3803
3804		store_values([], [], []).
3805		store_values([IDsHd|IDsTl], [VALsHd|VALsTl], [bind(IDsHd,VALsHd)|OutStateTl]) :-
3806		store_values(IDsTl, VALsTl, OutStateTl).
3807
3808
3809
3810
3811		/* the B syntax does allow multiple definitions in a LET: */
3812
3813		b_execute_let_definitions(Pred,LocalState,State,WF) :-
3814		is_a_conjunct(Pred,LHS,RHS),!,
3815		b_execute_let_definitions(LHS,LocalState,State,WF),
3816		b_execute_let_definitions(RHS,LocalState,State,WF).
3817		b_execute_let_definitions(b(equal(LHS,RHS),_,_),LocalState,State,WF) :- !,
3818		b_compute_expression(LHS,LocalState,State,LHSVal,WF),
3819		b_compute_expression(RHS,LocalState,State,RHSVal,WF),
3820		% TO DO: ideally we should check if LHS is a declared identifier and is only defined once
3821		kernel_objects:equal_object_optimized(LHSVal,RHSVal,b_execute_let_definitions).
3822		b_execute_let_definitions(b(lazy_let_pred(Id,AssignmentExpr,Body),_,_),LocalState,State,WF) :- !,
3823		add_lazy_let_id_and_expression(Id,AssignmentExpr,LocalState,State,NewLocalState,WF),
3824		b_execute_let_definitions(Body,NewLocalState,State,WF).
3825		b_execute_let_definitions(P,_L,_S,WF) :-
3826		add_internal_error_wf(b_interpreter,'Let contains a predicate which is not an equality: ',P,P,WF),fail.
3827
3828
3829		/* -----------------------------------------*/
3830		/* b_assign_function */
3831		/* -----------------------------------------*/
3832
3833		b_assign_values_or_functions([],[],_LS,_S,[],_WF,_OR).
3834		b_assign_values_or_functions([TExpr|ERest],[Value|VRest],LS,S,[bind(Id,New)|NRest],WF,OR) :-
3835		get_texpr_expr(TExpr,Expr),
3836	?	b_assign_value_or_function(Expr,Value,LS,S,Id,New,WF,OR),
3837		b_assign_values_or_functions(ERest,VRest,LS,S,NRest,WF,OR).
3838
3839		:- use_module(kernel_tools,[ground_value_check/2]).
3840		:- use_module(kernel_records,[overwrite_record_wf/5]).
3841		b_assign_value_or_function(identifier(Id),Value,_LS,_S,LHS_Id,FullValue,WF,_OR) :- !,
3842		LHS_Id=Id,
3843	?	equal_object_wf(FullValue,Value,b_assign_value_or_function(Id),WF).
3844		b_assign_value_or_function(function(Fun,Arg),Value,LocalState,InState,Id,FullValue,WF,OR) :- !,
3845		%b_compute_expression(Arg,LocalState,InState,ArgVal,WF),
3846		%expand_global_sets_but_not_closures(ArgVal,EArgVal),
3847		FunMNF = eval_must_not_fail('Assignment left-hand-side (or part thereof) could not be evaluated: ',Fun), % could be f(..)(..)
3848		b_compute_assign_expressions_when([Arg,FunMNF],LocalState,InState,[ArgVal,FunVal],WF,OR), % or should we pass the OR info around ?
3849		/* we do not examine local state: these vars cannot be modified by operations !? */
3850		(OR=output_required -> override(FunVal,ArgVal,Value,NewFun,WF)
3851		; ground_value_check((FunVal,ArgVal,Value),GRV),
3852		% wait until all arguments known so that we can effiently compute override
3853		blocking_override(GRV,FunVal,ArgVal,Value,NewFun,WF)),
3854		get_texpr_expr(Fun,Lhs),
3855		b_assign_value_or_function(Lhs,NewFun,LocalState,InState,Id,FullValue,WF,OR).
3856		b_assign_value_or_function(record_field(RecordExpr,FieldName),Value,LocalState,InState,LHS_Id,FullValue,WF,OR) :-
3857		!,
3858		% we allow nested record assignments: x'Field1'Field2 := Value
3859		b_compute_expression(RecordExpr,LocalState,InState,OldRecVal,WF),
3860		overwrite_record_wf(OldRecVal,FieldName,Value,NewRecVal,WF),
3861		get_texpr_expr(RecordExpr,Lhs),
3862		b_assign_value_or_function(Lhs,NewRecVal,LocalState,InState,LHS_Id,FullValue,WF,OR).
3863		b_assign_value_or_function(LHS,_Value,_LS,_InState,_Id,_FullValue,WF,_OR) :-
3864		add_internal_error_wf(b_interpreter,'Illegal LHS for assignment (must be ID(.) or ID\'Field or ID): ',LHS,LHS,WF),
3865		fail.
3866
3867		:- block blocking_override(-,?,?,?,?,?).
3868		blocking_override(_,FunVal,ArgVal,Value,NewFun,WF) :- override(FunVal,ArgVal,Value,NewFun,WF).
3869
3870
3871		/* -----------------------------------------*/
3872		/* b_execute_statements_in_parallel */
3873		/* -----------------------------------------*/
3874		/* execute a parallel composition of statements */
3875		:- assert_pre(b_interpreter:b_execute_statements_in_parallel(Ss,LS,State,_Os,WF,_Paths,_OR),
3876		(ground_check(Ss),type_check(LS,store),
3877		type_check(State,store),type_check(WF,wait_flag))).
3878		:- assert_post(b_interpreter:b_execute_statements_in_parallel(_Ss,_LS,_State,Os,WF,_Paths,_OR),
3879		(type_check(Os,store),type_check(WF,wait_flag))).
3880
3881		b_execute_statements_in_parallel([],_,_,[],_WF,[],_OR).
3882		b_execute_statements_in_parallel([Stmt|TS],LocalState,InState,OutState,WF,[Path1|TPath],OR) :-
3883	?	b_execute_statement(Stmt,LocalState,InState,OutState1,WF,Path1,OR),
3884	?	combine_updates(OutState1,OutState2,OutState), /* merge updates */
3885	?	b_execute_statements_in_parallel(TS,LocalState,InState,OutState2,WF,TPath,OR).
3886
3887
3888		%:- block combine_updates(-,-,?).
3889		%combine_updates(A,B,C) :- (B==[] -> A=C ; combine_updates_aux(A,B,C)).
3890
3891		% TO DO: investigate whether we could also unblock on second argument and copy it to result
3892		:- block combine_updates(-,?,?). % can also be used to merge states
3893		combine_updates([],X,R) :- !,R=X.
3894	?	combine_updates([H|T],Y,Res) :- !, Res=[H|Z], combine_updates(T,Y,Z).
3895		combine_updates(X,Y,Z) :- add_internal_error('Illegal call: ',combine_updates(X,Y,Z)),fail.
3896
3897
3898
3899		b_execute_initialisation_statement(Stmt,LS,In,Out,_OUTERWF,Path,OR) :-
3900		init_wait_flags(WF,[b_execute_initialisation_statement]),
3901		% each initialisation can be executed in isolation (except in CBC mode)
3902	?	b_execute_statement(Stmt,LS,In,Out,WF,Path,OR),
3903	?	ground_wait_flags(WF).
3904
3905		% replace certain parallels by init_parallel for better error reporting in INITIALISATION
3906		% will not be used in CBC mode (by set_up_initialisation or tc_initialise)
3907		translate_init_statements(b(Stmt,subst,I),b(TStmt,subst,I)) :-
3908		tp2(Stmt,I,TStmt).
3909		tp2(assign(LHS,RHS),I,parallel(S)) :- LHS=[_,_|_],
3910		% translate multiple assignment into parallel assignments
3911		maplist(generate_assignment(I),LHS,RHS,S),
3912		!.
3913		tp2(Stmt,I,init_statement(b(Stmt,subst,I))) :- %get_preference(provide_trace_information,true),
3914		wrap_stmt(Stmt),
3915		!.
3916		% TO DO: cover WHILE
3917		tp2(parallel(S),_,parallel(TS)) :- maplist(translate_init_statements,S,TS),
3918		!.
3919		tp2(sequence(A),_,sequence(LA)) :- !,maplist(translate_init_statements,A,LA).
3920		tp2(if(A),_,if(LA)) :- !, maplist(translate_init_statements,A,LA).
3921		tp2(if_elsif(Test,Body),_,if_elsif(Test,LBody)) :- !,
3922		translate_init_statements(Body,LBody).
3923		tp2(X,_,X). % :- functor(X,F,A), nl,nl,print(uncovered(F/A)),nl,nl.
3924
3925		wrap_stmt(assign(_,_)).
3926		wrap_stmt(becomes_element_of(_,_)).
3927		wrap_stmt(becomes_such(_,_)).
3928		wrap_stmt(assign_single_id(_,_)).
3929
3930		generate_assignment(I,V,RHS,b(init_statement(b(Assign,subst,I)),subst,I)) :-
3931		Assign = assign([V],[RHS]).
3932
3933
3934
3935		/* ---------------------------------------*/
3936		/* b_execute_top_level_statement */
3937		/* ---------------------------------------*/
3938
3939		/* this is just like b_execute_statement with the
3940		only difference that a PRE-condition is treated like
3941		a select, i.e., it does not generate an abort if used
3942		outside of its condition */
3943		b_execute_top_level_statement(TExpr,LocalState,InState,OutState,WF,Path,OR) :-
3944		get_texpr_expr(TExpr,Stmt),
3945	?	b_execute_top_level_statement2(Stmt,TExpr,LocalState,InState,OutState,WF,Path,OR).
3946		b_execute_top_level_statement2(precondition(PreCond,Body),TExpr,
3947		LocalState,InState,OutState,WF,Path,OR) :-
3948		preferences:preference(treat_outermost_pre_as_select,true),!,
3949		%debug_println(9,'Top level PRE treated as SELECT'),
3950		preference(ltsmin_do_not_evaluate_top_level_guards,NO_EVAL),
3951		(NO_EVAL=full ->
3952		debug_println(9,pge_guard_will_not_be_evaluated)
3953		; NO_EVAL=true, % do not evaluate guards detected by guard splitting
3954		get_texpr_info(TExpr,Info),member(prob_annotation('LTSMIN-GUARD'),Info) ->
3955		debug_println(9,ltsmin_guard_will_not_be_evaluated)
3956	?	; b_test_boolean_expression(PreCond,LocalState,InState,WF)
3957		),
3958		% b_tracetest_boolean_expression(PreCond,LocalState,InState,WF,one), % comment in for debugging
3959	?	b_execute_statement(Body,LocalState,InState,OutState,WF,Path,OR).
3960		b_execute_top_level_statement2(lazy_let_subst(Id,IdExpr,Body),_,
3961		LocalState,InState,OutState,WF,lazy_let(Path),OR) :-
3962		!,
3963		add_lazy_let_id_and_expression(Id,IdExpr,LocalState,InState,NewLocalState,WF),
3964		b_execute_top_level_statement(Body,NewLocalState,InState,OutState,WF,Path,OR).
3965		b_execute_top_level_statement2(_,TExpr,LocalState,InState,OutState,WF,Path,OR) :-
3966	?	b_execute_statement(TExpr,LocalState,InState,OutState,WF,Path,OR).
3967
3968
3969		/* -----------------------------*/
3970		/* b_execute_operation */
3971		/* -----------------------------*/
3972		/* execute a single operation */
3973
3974		try_get_op_name(FullOperation,_Name) :- var(FullOperation),!.
3975		try_get_op_name('-->'(FO,_),Name) :- !,try_get_op_name(FO,Name).
3976		try_get_op_name(FullOperation,Name) :- functor(FullOperation,Name,_).
3977
3978
3979
3980		:- assert_pre(b_interpreter:b_execute_top_level_operation_update(_Name,_FullOperation,InState,_NewState,_P),
3981		(ground_check(InState),type_check(InState,store))).
3982		:- assert_post(b_interpreter:b_execute_top_level_operation_update(Name,_FullOperation,_InState,NewState,_Path),
3983		(type_check(NewState,store),ground_check(Name))).
3984
3985
3986		b_execute_top_level_operation_update(Name,FullOperation,InState,Updates,Path) :-
3987	?	b_execute_top_level_operation_update_wf(Name,FullOperation,InState,Updates,Path,WF),
3988	?	ground_wait_flags(WF).
3989		%store:store_updates_and_normalise(Updates,InState,NewState).
3990
3991
3992		b_execute_top_level_operation_update_wf(Name,FullOperation,InState,Updates,Path,WF) :-
3993		init_wait_flags(WF,[]), % now treated by call_stack: [expansion_context(op(Name),[])]),
3994		% b_execute_operation2 below will push_wait_flag_call_stack_info
3995		try_get_op_name(FullOperation,Name), b_top_level_operation(Name),
3996		setup_result_input_values(Name,RIV),
3997		Info=unknown, % Info extracted later for top_level
3998	?	b_execute_operation2(Name,FullOperation,InState,Updates,_,RIV,_,true,Path,Info,WF,output_not_required).
3999
4000		% set up value of read output variables *before* operation call to some dummy value
4001		setup_result_input_values(Name,ResultInputValues) :-
4002		(get_preference(allow_operations_to_read_outputs,true),
4003		b_operation_reads_output_variables(Name,_Reads,TReadsInfo) ->
4004		maplist(setup_read_output_variable,TReadsInfo,ResultInputValues)
4005		%translate_bstate_limited(ResultInputValues,TS),
4006		%ajoin(['Warning: setting read output variables in ',Name,' to default values: ',TS],Msg),
4007		%add_warning(b_interpreter,Msg),
4008		%store_error_for_context_state(eventerror(Name,event_other_error(Msg),[]),_Id)
4009		; ResultInputValues=[]).
4010
4011		:- use_module(typing_tools,[any_value_for_type/2]).
4012		setup_read_output_variable(reads_result(_,Name,Type),bind(Name,Val)) :- any_value_for_type(Type,Val).
4013
4014		% for use by CBC:
4015		b_execute_top_level_operation_wf(Name,FullOperation,ParaVals,ResultVals,InState,NewState,Path,WF) :-
4016		try_get_op_name(FullOperation,Name),
4017		if(b_top_level_operation(Name),true,
4018		(add_internal_error('Unknown operation name for b_execute_top_level_operation_wf: ',Name),fail)
4019		),
4020		% call before execute operation to copy over results immediately in case b_execute_operation2 generates choice points:
4021		store_intermediate_updates_wf(InState,Updates,NewState,operation(Name),WF), % no normalising is better for constraint propagation
4022		% TO DO?: copy over unmodified variables b_get_machine_variables(Variables),copy_unmodified_variables(Variables,OpName,InState,NewState)
4023		setup_result_input_values(Name,RIV),
4024		Info=unknown, % Info extracted later for top_level
4025		b_execute_operation2(Name,FullOperation,InState,Updates,ParaVals,RIV,ResultVals,true,Path,Info,WF,output_required).
4026		% we should ensure that Operation part is executed to instantiate NewOutState skeleton
4027
4028
4029
4030		% Note : if the argument OR (OutputRequired) has value output_required this indicates that the output
4031		% an operation or its effect is required (e.g., because of sequential composition) and the constraint solver
4032		% should not delay computing the effect of the operation
4033		% Atelier-B Handbook 6.16: [R <- op (E)]P = [X := E ; S ; R :=Y] P where op defined by X <- op(Y) = S
4034		b_execute_operation_with_parameters(Name,LocalState,InState,Results,Parameters,OutState,ParamValues,ResultValues,Path,Info,WF,OR) :-
4035		(b_is_operation_name(Name)
4036		-> b_compute_expressions(Parameters,LocalState,InState,ParamValues,WF),
4037		% TO DO : remove local vars from InState
4038		(b_operation_reads_output_variables(Name,_Reads,TReadsInfo)
4039		-> % format('Transferring outputs ~w ~w~n ~w~n',[Name,_Reads,TReadsInfo]),
4040		maplist(output_parameters_value(LocalState,InState,Results,Info,WF),TReadsInfo,ResultInputValues)
4041		; ResultInputValues=[]),
4042	?	call_b_execute_operation2(Name,InState,OutState,ParamValues,ResultInputValues,ResultValues,false,Path,Info,WF,OR)
4043		; add_internal_error('Unknown B operation, cannot call: ',
4044		b_execute_operation_with_parameters(Name,LocalState,InState,Results,Parameters,
4045		OutState,ParamValues,ResultValues,Path,Info,WF,OR)),
4046		fail
4047		).
4048
4049
4050		%b_execute_operation_in_expression(Name,_LocalState,_InState,_Parameters,_Value,Info,_WF) :-
4051		% % This clause is disabled: sometimes variables are marked as read even though they are not:
4052		% % the analysis is not precise due to sequential composition, CASE statements, ...
4053		% b_operation_reads_output_variables(Name,_Reads,_TReadsInfo),!,
4054		% add_error(b_interpreter,'Operation that reads output cannot be called in expression: ',Name,Info),
4055		% fail.
4056		b_execute_operation_in_expression(Name,LocalState,InState,Parameters,Value,Info,WF) :-
4057		% TODO: check that this is a query operation; probably done in type checker
4058		OR=output_required, % alternative: OR=output_not_required,
4059		setup_result_input_values(Name,ResultInputValues),
4060		b_compute_expressions(Parameters,LocalState,InState,ParamValues,WF),
4061		b_get_operation_normalized_read_write_info(Name,Read,_Modified), % Modified should be []
4062		create_inner_wait_flags(WF,operation_call_in_expr,OpWF),
4063		ground_value_check(ParamValues,ParaGround),
4064		exclude(unused_variable(Read),InState,IS),
4065		ground_state_check(IS,StateGround),
4066		% TO DO: in case of recursion it may be good to delay executing sub-operation until some WF is set
4067		call_b_execute_operation2(Name,IS,_OutState,ParamValues,ResultInputValues,ResultValues,false,_Path,Info,OpWF,OR),
4068		ground_inner_wf(ParaGround,StateGround,OpWF),
4069		make_couplise(ResultValues,Value).
4070
4071		% ground inner waitflags when parameters and relevant read variables fully known
4072		:- block ground_inner_wf(-,?,?), ground_inner_wf(?,-,?).
4073		ground_inner_wf(_,_,WF) :-
4074	?	ground_inner_wait_flags(WF).
4075
4076		call_b_execute_operation2(Name,InState,OutState,ParamValues,ResultInputValues,ResultValues,false,Path,Info,WF,OR) :-
4077		% TODO: insert operation call as additional error context; stack trace
4078	?	runtime_profiler:profile_single_call(Name,unknownStateId, b_interpreter:
4079		b_execute_operation2(Name,_,InState,OutState,ParamValues,ResultInputValues,ResultValues,false,Path,Info,WF,OR)
4080		).
4081
4082		output_parameters_value(LocalState,InState,Results,_,WF,reads_result(Index,ID,_Type),bind(ID,Val)) :-
4083		nth1(Index,Results,ReadResultTID),!,
4084		def_get_texpr_id(ReadResultTID,ReadID),
4085		(lookup_value_without_check(ReadID,LocalState,InState,Val)
4086		-> true %check_not_undefined(Val,ReadID,ReadResultTID)
4087		; add_error_wf(output_parameters,'Could not obtain value for read output parameter: ',ReadID,ReadResultTID,WF),
4088		Val = term(undefined)).
4089		output_parameters_value(_LocalState,_InState,_Results,Info,WF,reads_result(_Index,ID,_Type),bind(ID,Val)) :-
4090		add_error_wf(output_parameters,'Could not obtain value for read output parameter: ',ID,Info,WF),
4091		Val = term(undefined).
4092
4093		% TO DO: use this ?
4094		%:- block check_not_undefined(-,?,?).
4095		%check_not_undefined(term(undefined),ReadID,ReadResultTID) :- !,
4096		% add_error(output_parameters_value,'Output parameter not assigned to: ',ReadID,ReadResultTID).
4097		%check_not_undefined(_,_,_).
4098
4099		:- use_module(probsrc(succeed_max),[assert_max_reached/1]).
4100		% ResultInputValues: in Atelier-B result parameters can also be read !
4101		b_execute_operation2(Name,Operation,InState,Updates,ParaValues,ResultInputValues,ResultValues,_TopLevel,TransInfo,_,_WF,_OR) :-
4102		ResultInputValues = [], % in this case the operation's behaviour also depends on current value of output variables
4103		lookup_cached_transitions(Name,InState,Info,Solutions),!,
4104		(member(max_reached,Info) -> assert_max_reached(Name) ; true),
4105	?	member(trans_cached(ParaValues,ResultValues,Updates,TransInfo),Solutions),
4106		create_full_operation(Name,ResultValues,ParaValues,ResultValues,Operation).
4107
4108		b_execute_operation2(Name,Operation,InState,NewOutState,ParaValues,ResultInputValues,ResultValues,
4109		TopLevel,TransInfo,Info,WF,OutputRequired) :-
4110		b_get_machine_operation_for_animation(Name,Results,Parameters,Body,OType,TopLevel,OpPos),
4111		%% % we do not want skip the evaluation of a guard of an operation with parameters
4112		%% (Parameters==[] ->true; retractall(pge_algo:do_not_evaluate_guard)),
4113		(Info=unknown, TopLevel==true -> CallInfo=OpPos ; CallInfo=Info),
4114		push_wait_flag_call_stack_info(WF,operation_call(Name,ParaValues,CallInfo),WF2),
4115	?	b_execute_operation3(OType,Name,Operation,
4116		InState,NewOutState,
4117		Body,Parameters,ParaValues,Results,ResultInputValues,ResultValues,TopLevel,TransInfo,WF2,OutputRequired).
4118
4119		create_full_operation(Name,Results,ParaValues,ResultValues,FullOperation) :-
4120		%length(ParaValues,Len),print(create_full_op(Name,Len)),nl,
4121		Operation =.. [Name|ParaValues], % TO DO: catch if > 255 args (max_arity)
4122		( Results == [] -> /* we have an ordinary operation */
4123		FullOperation = Operation
4124		; FullOperation = '-->'(Operation,ResultValues)
4125		).
4126
4127		b_execute_operation3(classic,Name,Operation,InState,NewOutState,
4128		Body,Parameters,ParaValues,Results,ResultInputValues,NormalisedResultValues,TopLevel,
4129		[], % [path(Path)], % as path is currently filtered out anyway and not stored !
4130		WF,OR) :-
4131		%print('Attempting Operation ----> '),print(Name),nl,
4132		empty_state(EmptyState),
4133	?	set_up_typed_localstate(Parameters,ParaValues,ParamTypedVals,EmptyState,LocalState,positive),
4134		l_expand_and_normalise_values(ParaValues,NormalisedParaValues,Parameters), % not useful for call_b_execute_operation2
4135		create_full_operation(Name,Results,NormalisedParaValues, % ditto
4136		NormalisedResultValues,Operation),
4137		set_up_undefined_localstate_with_predefined(Results,ResultInputValues,InState,NewInState),
4138		/* to avoid error messages with sequential composition (store_intermediate_updates) */
4139		check_additional_guard(TopLevel,LocalState,NewInState,WF),
4140		(TopLevel==true
4141	?	-> b_execute_top_level_statement(Body,LocalState,NewInState,OutState,WF,_Path1,OR)
4142	?	; b_execute_statement(Body,LocalState,NewInState,OutState,WF,_Path2,OR)
4143		),
4144		b_tighter_enumerate_all_values(ParamTypedVals,WF), % moved afer execute for performance reasons; see PerformanceTests/ParameterEnumeration.mch
4145		% print_bt_message('Operation Successful ------> '),
4146		(preferences:preference(treat_outermost_pre_as_select,true),
4147		preferences:preference(require_operations_to_assign_all_outputs,true)
4148		-> ReportError = true ; ReportError = false),
4149		get_results(Results,OutState,NormalisedResultValues,NewOutState,ReportError,normalise_results,WF).
4150		b_execute_operation3(eventb_operation(ChangeSet,ParaValues,Operation),
4151		_Name,Operation, InState,Updates,
4152		TBody,Parameters,ParaValues,[],[],[],true,TransInfo,WF,OutputRequired) :-
4153		% TO DO: check if need to pass _OutputRequired to b_event
4154	?	b_execute_event_with_change_set_wf(TBody,Parameters,ParaValues,InState,ChangeSet,Updates,TransInfo,WF,OutputRequired).
4155
4156		:- use_module(b_global_sets,[add_prob_deferred_set_elements_to_store/3]).
4157		% additional guards can be set by the user to constrain/direct the execution of operations
4158		check_additional_guard(TopLevel,LocalState,State,WF) :-
4159		(TopLevel==true,
4160		bmachine:b_machine_temp_predicate(TempPred)
4161		/* an additional precondition typed in by the user */
4162		-> check_state_skeleton_bound(LocalState,LB),
4163		check_state_skeleton_bound(State,BB),
4164		check_additional_guard_when_bound(LB,BB,TempPred,LocalState,State,WF)
4165		; true
4166		).
4167
4168		:- block check_additional_guard_when_bound(-,?,?, ?,?,?), check_additional_guard_when_bound(?,-,?, ?,?,?).
4169		check_additional_guard_when_bound(_,_,TempPred,LocalState,State,WF) :-
4170		(debug_mode(on) -> print(check_additional_guard),nl, print_bexpr(TempPred),nl ; true),
4171		add_prob_deferred_set_elements_to_store(State,BState1,visible),
4172		b_test_boolean_expression(TempPred,LocalState,BState1,WF).
4173
4174		% additional properties can either be set by user or by command-line or by VALUES clause
4175		add_additional_properties(OldProperty,NewProperty) :-
4176		(bmachine:b_machine_temp_predicate(TempPred) % this overrides additional property !
4177		-> conjunct_predicates([TempPred,OldProperty],NewProperty)
4178		; findall(AddPred,b_machine_additional_property(AddPred),L),
4179		(L=[] -> NewProperty = OldProperty
4180		; conjunct_predicates([OldProperty|L],NewProperty)
4181		)
4182		).
4183
4184		% get removes results from OutState
4185		filter_results(Results,OutState,NewOutState,WF) :-
4186		get_results(Results,OutState,_ResultValues,NewOutState,false,do_not_normalise,WF).
4187		get_results(Results,OutState,ResultValues,NewOutState,ReportError,Normalise,WF) :-
4188		(Results==[] -> (ResultValues,NewOutState) = ([],OutState)
4189		; get_results1(Results,OutState,ResultValues,NewOutState,ReportError,Normalise,WF)).
4190		:- block get_results1(?,-,?,?,?,?,?).
4191		get_results1([],OutState,[],OutState,_ReportError,_Normalise,_WF).
4192		get_results1([R|Results],OutState,[NRV|ResultValues],NewOutState,ReportError,Normalise,WF) :-
4193		def_get_texpr_id(R,ResultId),
4194		lookup_and_delete_value(ResultId,RV,OutState,OutState2,ReportError,WF,Finished),
4195		get_results2(Finished,R,Results,RV,NRV,OutState2,ResultValues,NewOutState,ReportError,Normalise,WF).
4196		:- block get_results2(-,?,?,?,?,?,?,?,?,?,?).
4197		get_results2(_,R,Results,RV,NRV,OutState2,ResultValues,NewOutState,ReportError,Normalise,WF) :-
4198		(Normalise==normalise_results -> normalise_value_for_var(R,true,RV,NRV)
4199		;
4200		NRV=RV), % Maybe we should not normalise in CBC mode ?
4201		get_results1(Results,OutState2,ResultValues,NewOutState,ReportError,Normalise,WF).
4202
4203
4204
4205		/* ------------------------------------------------------------------ */
4206		/* SET UP CONSTANTS */
4207		/* ------------------------------------------------------------------ */
4208
4209		:- use_module(static_ordering).
4210
4211		:- volatile no_solution_found_for_constants/0, properties_were_filtered/1,
4212		unsat_properties_component/2, unsat_properties_enumeration_warning/1, unsat_properties_abort_error/1,
4213		unsat_properties_conjunct_inside_component/4.
4214		:- dynamic no_solution_found_for_constants/0,
4215		properties_were_filtered/1,
4216		unsat_properties_component/2, unsat_properties_enumeration_warning/1,
4217		unsat_properties_abort_error/1,
4218		unsat_properties_conjunct_inside_component/4.
4219
4220		reset_unsat_component_infos :-
4221		retractall(unsat_properties_component(_,_)),
4222		retractall(unsat_properties_enumeration_warning(_)),
4223		retractall(unsat_properties_abort_error(_)),
4224		retractall(unsat_properties_conjunct_inside_component(_,_,_,_)).
4225
4226		:- use_module(b_interpreter_components,[unsat_conjunct_inside_component/4, unsat_component_abort_error/1,
4227		unsat_component_enumeration_warning/1]).
4228		% store information about unsatisfiable components for later usage
4229		% will only be called when no solution found for components
4230		assert_unsat_component_infos(_) :-
4231	?	unsat_component(X,FalseOrUnknown), % from b_interpreter_components
4232		assertz(unsat_properties_component(X,FalseOrUnknown)),fail.
4233		assert_unsat_component_infos(_) :-
4234		unsat_component_enumeration_warning(X), % from b_interpreter_components
4235		assertz(unsat_properties_enumeration_warning(X)),fail.
4236		assert_unsat_component_infos(_) :-
4237		unsat_component_abort_error(X), % from b_interpreter_components
4238		assertz(unsat_properties_abort_error(X)),fail.
4239		assert_unsat_component_infos(_) :-
4240	?	unsat_conjunct_inside_component(X,BE,Status,Reason), % from b_interpreter_components
4241		assertz(unsat_properties_conjunct_inside_component(X,BE,Status,Reason)),fail.
4242		assert_unsat_component_infos(Status) :-
4243	?	(unsat_conjunct_inside_component(_,_,false,_) -> Status = false
4244		; unsat_component(X,false), \+ unsat_component_abort_error(X) -> Status = false % what about enumeration warnings?
4245		; Status=unknown).
4246
4247
4248		all_unsat_components_marked_prob_ignore :-
4249		unsat_properties_conjunct_inside_component(_,_,unknown,'prob-ignore'), % at least one prob-ignore was used
4250		!,
4251		\+ non_ignore_unsat_component.
4252
4253		non_ignore_unsat_component :-
4254		unsat_properties_conjunct_inside_component(_,_,Status,Reason),
4255		\+ (Status = unknown, Reason = 'prob-ignore').
4256
4257		tcltk_unsatisfiable_components_exist :- unsat_or_unknown_component_exists,!.
4258
4259		%tcltk_unsatisfiable_components(list(UnsatComponents)) :-
4260		% findall(C,unsat_properties_component(C),UnsatComponents), UnsatComponents\=[].
4261
4262		get_property_components(Components) :-
4263		b_machine_has_constants_or_properties,
4264		b_get_properties_from_machine(Properties),
4265		add_additional_properties(Properties,NewProperty),
4266		bsyntaxtree:predicate_components(NewProperty,Components),!.
4267		get_property_components([]).
4268
4269		:- dynamic uses_implementable_integers/0.
4270		:- dynamic min_max_integer_value_used/2.
4271
4272
4273		tcltk_quick_describe_unsat_properties(list(FullDescr),STATUS) :-
4274		retractall(uses_implementable_integers),
4275		retractall(min_max_integer_value_used(_,_)), assertz(min_max_integer_value_used(none,none)),
4276		get_property_components(Components),
4277		(unsat_properties_conjunct_inside_component(_,_,false,_)
4278		-> STATUS='FALSE'
4279		; all_unsat_components_marked_prob_ignore
4280		-> STATUS = 'prob-ignore'
4281		; STATUS='UNKNOWN'
4282		),
4283		findall(TP, (unsat_properties_conjunct_inside_component(CompNr,P,_Status,_ReasonMsg), % find individual conjuncts
4284		% Status can be false or unknown
4285		nth1(CompNr,Components,component(FullPred,_Vars)),
4286		check_uses_implementable_integers(FullPred), % for the min-max one may need to look at the entire component !
4287		translate_bexpression_with_limit(P,TrP),
4288		get_component_enum_warning_message(CompNr,EnumWarningAbortMsg),
4289		(EnumWarningAbortMsg = '' -> Prefix = '' ; Prefix = '\n '),
4290		get_span_msg(P,'\n ',SpanMsg),
4291		ajoin([' * ',TrP,Prefix,EnumWarningAbortMsg,SpanMsg,'\n'],TP)),
4292		D1),
4293		findall([Msg1,PS|DescrVars],
4294		(get_unsat_component_description(Components,CompNr,MaxCompNr,
4295		Size,PS,DescrVars,EnumWarningAbortMsg,SpanMsg),
4296		ajoin([' * Predicate Component ',EnumWarningAbortMsg,CompNr,'/',MaxCompNr,
4297		' (with ',Size,' conjunct(s))',SpanMsg, ':'],Msg1)),
4298		UC),
4299		append(UC,UCL), % join all component descriptions
4300		(D1=[]
4301		% TO DO: adapt message for enumeration warning
4302		-> Descr = D2,
4303		(UCL=[] -> D2 = ['The properties were satisfiable']
4304		; D2 = ['No solution found for the following predicates: '|UCL]
4305		)
4306		; Descr = ['The following properties prevented finding a solution:\n'|D12],
4307		% Comment: the predicate can trigger the computation of another earlier registered predicate
4308		% Example f = {1|->2} & f: A --> B & A = 1..5; A=1..5 triggers the check for f
4309		(UCL=[] -> D2=[]
4310		; D2 = ['\nIn addition no solution was found for the following predicates: '|UCL]
4311		),
4312		append(D1,D2,D12)),
4313		findall(W,other_warning(W),Warnings),
4314		(Warnings = [] -> FullDescr=Descr ; append(Descr,['\nWARNINGS/MESSAGES:'|Warnings],FullDescr)).
4315
4316		% called by predicate_debugger:
4317		get_unsat_component_predicate(CompNr,Predicate,Vars) :-
4318		unsat_properties_component(CompNr,_FalseOrUnknown),
4319		get_property_components(Components),
4320		nth1(CompNr,Components,component(Predicate,Vars)).
4321
4322		get_unsat_component_description(Components,CompNr,MaxCompNr,Size,PS,DescrVars,EnumWarningAbortMsg,SpanMsg) :-
4323		unsat_properties_component(CompNr,_),
4324		\+ unsat_properties_conjunct_inside_component(CompNr,_,_,_), % we have not yet dealt with this component in first findall above
4325		nth1(CompNr,Components,component(Pred,Vars)),
4326		length(Components,MaxCompNr),
4327		size_of_conjunction(Pred,Size),
4328		describe_constants(Vars,DescrVars),
4329		check_uses_implementable_integers(Pred), % store information in case it does use implementable integers for later user messages
4330		(debug_mode(on) -> Lim = 1500 ; Lim = 250),
4331		translate_bexpression_with_limit(Pred,Lim,PS),
4332		get_component_enum_warning_message(CompNr,EnumWarningAbortMsg),
4333		% note: sometimes we have a conjunction with empty span info, but different conjuncts (possibly from different files):
4334		get_span_msg(Pred,'\n ',SpanMsg).
4335
4336		get_span_msg(Pred,Prefix,SpanMsg) :-
4337		(extract_span_description(Pred,SpanStr) -> ajoin([Prefix,SpanStr],SpanMsg) ; SpanMsg = '').
4338
4339		get_component_enum_warning_message(CompNr,EnumWarningAbortMsg) :-
4340		(unsat_properties_enumeration_warning(CompNr)
4341		->(unsat_properties_abort_error(CompNr)
4342		-> EnumWarningAbortMsg = '[** with Enumeration Warning and WD-ERROR **] '
4343		; EnumWarningAbortMsg = '[* with Enumeration Warning *] ')
4344		; (unsat_properties_abort_error(CompNr)
4345		-> EnumWarningAbortMsg = '[** with WD-ERROR **] '
4346		; EnumWarningAbortMsg = '')
4347		).
4348
4349		describe_constants([],R) :- !,R=[].
4350		describe_constants(Vars,['* over identifiers : '|Vars]).
4351
4352		check_uses_implementable_integers(_) :- specfile:eventb_mode,!. % cannot use implementable integers
4353		check_uses_implementable_integers(_) :- uses_implementable_integers,!. % no need to check another component
4354		check_uses_implementable_integers(Pred) :-
4355		(uses_implementable_integers(Pred)
4356		-> assertz(uses_implementable_integers),
4357		retract(min_max_integer_value_used(Min,Max)),
4358		min_max_integer_value_used(Pred,Min,Max,NewMin,NewMax),
4359		assertz(min_max_integer_value_used(NewMin,NewMax))
4360		; true).
4361
4362		other_warning(W) :- uses_implementable_integers,
4363		preferences:get_preference(minint,MININT),
4364		preferences:get_preference(maxint,MAXINT),
4365		min_max_integer_value_used(Min,Max),
4366		( (number(Min),Min<MININT ; number(Max),Max>MAXINT)
4367		-> ajoin(['\n MININT...MAXINT only set to ',MININT,'..',MAXINT,' but integers used at least from ',Min,'..',Max],W)
4368		; (MAXINT < 127 ; MININT > -128)
4369		-> ajoin(['\n MININT...MAXINT possibly too small: ',MININT,'..',MAXINT],W)).
4370		% TO DO: we could also extract explicit integer values used in the component and compare them against MININT/MAXINT
4371		other_warning(W) :- bmachine_eventb:deferred_set_equality_without_enumeration_axioms(X,_Set),
4372		translate_bexpression_with_limit(X,XS),
4373		ajoin(['\n Set not recognized as enumerated: ',XS],W).
4374		% TO DO: generate warning if MAXINT/MININT small and NAT,NAT1 or INT was used in component(s) above
4375
4376		% call if tcltk_quick_describe_unsat_properties fails:
4377		% TODO: maxint warning above
4378		generate_unsat_properties_warnings :- uses_implementable_integers,
4379		preferences:get_preference(minint,MININT),
4380		preferences:get_preference(maxint,MAXINT),
4381		min_max_integer_value_used(Min,Max),
4382		(number(Min),Min<MININT ; number(Max),Max>MAXINT),
4383		ajoin(['MININT...MAXINT only set to ',MININT,'..',MAXINT,' but integers used at least from ',Min,'..',Max],Msg),
4384		add_warning(setup_constants_unknown,Msg),
4385		fail.
4386		generate_unsat_properties_warnings :-
4387		bmachine_eventb:deferred_set_equality_without_enumeration_axioms(X,Set),
4388		translate_bexpression_with_limit(X,TX),
4389		Eq = b(equal(X,Set),pred,[]),
4390		ajoin(['Deferred SET ',TX,' was not recognized as an enumerated set, you may want to use partition instead of the equality: '],Msg),
4391		add_warning(setup_constants_unknown,Msg,Eq,X),
4392		fail.
4393		generate_unsat_properties_warnings.
4394
4395		% -------------
4396
4397		% Complete is either complete_properties or partial_properties if properties were marked as ignore
4398		b_set_up_concrete_constants(NormalisedConstantsState,Complete) :-
4399		reset_unsat_component_infos,
4400		retractall(properties_were_filtered(_)),
4401		(no_solution_found_for_constants -> true ; assertz(no_solution_found_for_constants)),
4402		% preference(allow_incomplete_partial_setup_constants,AllowSkipping),
4403		reset_component_info(true),
4404		b_machine_has_constants_or_properties,
4405		b_get_machine_constants(UnsortedConstants),
4406		!,
4407		silent_mode(SilentMode),
4408	?	(SilentMode=on -> true ; bt_start_ms_timer('SETUP_CONSTANTS')), % TO DO: store time for unsat core
4409		b_get_properties_from_machine(MProperties),
4410		(get_preference(use_ignore_pragmas,true) % filter out prob-ignore predicates here
4411		-> conjunction_to_list(MProperties,LMP), % TO DO avoid this conversion and back
4412		exclude_count(predicate_has_ignore_pragma, LMP,LMP2,Excluded), % exclude props marked as prob-ignore
4413		conjunct_predicates(LMP2,MProperties2),
4414		%format('FILTERED (~w): ',[Excluded]),translate:print_bexpr(MProperties2),nl,
4415		(Excluded=0 -> Complete=complete_properties
4416		; assertz(properties_were_filtered(Excluded)), Complete=partial_properties)
4417		; MProperties2=MProperties,
4418		Complete=complete_properties
4419		),
4420		add_additional_properties(MProperties2,Properties),
4421		project_onto_static_assertions(Properties,UnsortedConstants,PProperties,PUnsortedConstants),
4422	?	solve_properties(PProperties,PUnsortedConstants,ConstantsState),
4423	?	(SilentMode=on -> true ; bt_stop_ms_timer('SETUP_CONSTANTS')),
4424		normalise_store(ConstantsState,NormalisedConstantsState),
4425		retractall(no_solution_found_for_constants). /* ensure that b_partial_set_up_concrete_constants fails */
4426		b_set_up_concrete_constants([],complete).
4427
4428
4429		% solve already projected and filtered properties and constants, return state with solution for constants
4430		% cbc_solve_timed almost does what we want; but looks at current state; see solve_free_aux
4431		% TODO: move this to a separate module and add cdclt
4432		solve_properties(PProperties,PUnsortedConstants,ConstantsState) :-
4433		get_preference(use_solver_on_load,Solver),
4434	?	solve_properties(Solver,PProperties,PUnsortedConstants,ConstantsState).
4435
4436		solve_properties(sat,Properties,_TypedConstants,ConstantsState) :- !,
4437	?	b2sat:solve_predicate_with_satsolver_free(Properties, ConstantsState,Result,[]),
4438		Result=solution(_).
4439		solve_properties('sat-z3',Properties,_TypedConstants,ConstantsState) :- !,
4440		b2sat:solve_predicate_with_satsolver_free(Properties, ConstantsState,Result,[use_satsolver(z3)]),
4441		Result=solution(_).
4442		solve_properties(cdclt,Properties,_TypedConstants,ConstantsState) :- !,
4443		cdclt_solver:cdclt_solve_predicate(Properties, _,Result),
4444		Result=solution(ConstantsState).
4445		solve_properties(kodkod,PProperties,PUnsortedConstants,ConstantsState) :- !,
4446	?	solve_properties(prob,PProperties,PUnsortedConstants,ConstantsState). % Kodkod processing is done elswehere
4447		solve_properties(prob,PProperties,PUnsortedConstants,ConstantsState) :- !,
4448		(preferences:preference(use_static_ordering,true)
4449		-> sort_ids_by_usage(PUnsortedConstants,PProperties,Constants,no_warnings), % no_warnings as Ids could be used in operations, assertions, ...
4450		set_up_typed_localstate(Constants,_FreshVars,TypedVals,[],SortedState,positive),
4451	?	reorder_state(PUnsortedConstants,SortedState,ConstantsState)
4452		; Constants = PUnsortedConstants,
4453	?	set_up_typed_localstate(Constants,_FreshVars,TypedVals,[],ConstantsState,positive)
4454		),
4455		% now try and load saved constants from file for sub-machines when -cache is used:
4456	?	load_partial_constants(ConstantsState,PProperties,LPProperties), % Note: this can backtrack
4457		reset_component_info(true), % reset in case load_partial_constants backtracks! relevant for test 2112
4458		b_global_sets:static_symmetry_reduction_for_global_sets(ConstantsState),
4459	?	b_trace_test_components_full(LPProperties,ConstantsState,TypedVals).
4460		solve_properties(SolverName,Properties,_TypedConstants,ConstantsState) :-
4461		temporary_set_preference(z3_solve_for_animation, true,Chng),
4462		call_cleanup(smt_solvers_interface:smt_solve_predicate_free(SolverName, Properties, ConstantsState),
4463		reset_temporary_preference(z3_solve_for_animation,Chng)).
4464
4465
4466		b_trace_test_components_full(LPProperties,ConstantsState,TypedVals) :-
4467		init_wait_flags_and_push_call_stack(no_wf_available,operation_call('SETUP_CONSTANTS',[],unknown),WF),
4468	?	b_trace_test_components_wf(LPProperties,ConstantsState,TypedVals,WF),
4469		ground_wait_flags(WF), % WF is just a dummy waitflag to pass call stack info
4470		(unsat_or_unknown_component_exists -> (!,fail) ; true). % otherwise some expressions were skipped; use partial_set_up
4471
4472		:- volatile project_properties_on_identifiers/1.
4473		:- dynamic project_properties_on_identifiers/1.
4474		set_projection_on_static_assertions(ALL) :-
4475		% set interpreter in mode which projects out all constants not needed
4476		% for static assertion checking; all variables are also projected out
4477		retractall(project_properties_on_identifiers(_)),
4478		(b_get_assertions(ALL,dynamic,[]) -> true
4479		; nl,print('*** WARNING: DYNAMIC B ASSERTIONS NOT EMPTY'),nl,nl),
4480	?	b_get_assertions(ALL,static,L),
4481		(L=[] -> nl,print('*** WARNING: NO STATIC B ASSERTIONS ***'),nl,nl ; true),
4482		conjunct_predicates(L,Conj),
4483		(debug_mode(on) -> print('Static Assertion: '),translate:print_bexpr(Conj),nl ; true),
4484		bsyntaxtree:predicate_identifiers(Conj,IDs),
4485		(debug_mode(on) -> print('IDS: '), print(IDs),nl ; true),
4486		assertz(project_properties_on_identifiers(IDs)).
4487
4488		% optionally project properties onto those required for checking assertions
4489		project_onto_static_assertions(Properties,Constants,NewProperties,NewConstants) :-
4490		%% set_projection_on_static_assertions(main), %% main or all %% set by probcli if we_need_only_static_assertions
4491		project_properties_on_identifiers(ProjIDs),
4492		bsyntaxtree:project_predicate_on_identifiers(Properties,ProjIDs,NewProperties,PIDs,_),
4493		sort(PIDs,SIPDs),
4494		debug_println(9,projecting(SIPDs)),
4495		include(keep_constant(SIPDs),Constants,NewConstants),!. % Constants is a typed identifier list.
4496		project_onto_static_assertions(Properties,Constants,Properties,Constants).
4497
4498		keep_constant(SIPDs,TypedID) :- get_texpr_id(TypedID,ID),ord_member(ID,SIPDs).
4499
4500
4501
4502		/* can be called if b_set_up_concrete_constants failed; will partially set up the state using values found in first ground value propagation phase */
4503		:- use_module(specfile,[get_specification_description/2]).
4504		b_partial_set_up_concrete_constants(NormalisedConstantsState) :-
4505		assert_unsat_component_infos(Status), % Status is false or unknown
4506		no_solution_found_for_constants,
4507		(b_partial_set_up_concrete_constants2(NormalisedConstantsState,Status)
4508		-> generate_unsat_properties_warnings
4509		; generate_unsat_properties_warnings,fail).
4510
4511		b_partial_set_up_concrete_constants2(NormalisedConstantsState,Status) :-
4512		b_get_machine_constants(Constants),
4513		Constants \= [],
4514	?	(det_solution_for_constant_was_stored(Cst1) -> true), % we have found a solution for at least one constant
4515		%set_up_typed_localstate(Constants,[],ConstantsState), -> can create call_residue due to typing fd/2 values
4516		findall(bind(ID,_),(member(TID,Constants),def_get_texpr_id(TID,ID)),ConstantsState),
4517		formatsilent('SETUP_CONSTANTS not successful, but solutions were found for some constants (e.g., ~w):~n',[Cst1]),
4518		(fill_in_det_solutions(ConstantsState,FC)
4519		-> All=all, TMSG = [')']
4520		; All=some, TMSG = [', e.g., ',Cst1,')']
4521		),
4522		(preference(allow_incomplete_partial_setup_constants,true)
4523		-> true
4524		; % fill_in_det_solutions will fail if not all constants valued and
4525		% if allow_incomplete_partial_setup_constants is false
4526		get_specification_description(properties,PS),
4527		% TO DO: determine if time-out occurred or not
4528		(Status=false
4529		-> ajoin([PS,' are unsatisfiable (but ',All,' CONSTANTS valued'|TMSG],Msg),
4530		add_error(setup_constants_inconsistent,Msg)
4531		; unsat_properties_abort_error(_)
4532		-> ajoin([PS,' are unknown due to well-definedness error(s) (but ',All,' CONSTANTS valued'|TMSG],Msg),
4533		add_error(setup_constants_unknown,Msg)
4534		; unsat_component_enumeration_warning(_)
4535		-> ajoin([PS,' are unknown due to enumeration warning(s) (but ',All,' CONSTANTS valued'|TMSG],Msg),
4536		add_error(setup_constants_unknown,Msg)
4537		; all_unsat_components_marked_prob_ignore
4538		-> ajoin([PS,' are unknown due to prob-ignore pragmas (but ',All,' CONSTANTS valued'|TMSG],Msg),
4539		add_message(setup_constants_unknown,Msg)
4540		;
4541		ajoin([PS,' are unknown (but ',All,' CONSTANTS valued'|TMSG],Msg),
4542		% typical message: but some CONSTANTS valued
4543		add_error(setup_constants_unknown,Msg)
4544		),
4545		All=all % only continue if all constants valued
4546		),
4547		normalise_store(FC,NormalisedConstantsState).
4548
4549
4550		:- use_module(store,[no_value_for_variable/2]).
4551		fill_in_det_solutions([],[]).
4552		fill_in_det_solutions([bind(Var,Val)|T],[bind(Var,FVal)|FT]) :-
4553		(det_solution_for_constant(Var,Val)
4554		-> (silent_mode(on) -> true ; write(' --det--> '),print_term_summary(bind(Var,Val))),
4555		FVal=Val
4556		; %format('No (deterministic) solution was found or stored for constant: ~w~n',[Var]), % message printed by det_solution_for_constant
4557		(preference(allow_incomplete_partial_setup_constants,true)
4558		-> no_value_for_variable(FVal,Var)
4559		; format('Aborting SETUP_CONSTANTS (set preference ALLOW_INCOMPLETE_SETUP_CONSTANTS to TRUE to allow ProB to proceed without having values for all CONSTANTS)~n',[]),
4560		fail
4561		)
4562		),
4563		fill_in_det_solutions(T,FT).
4564
4565
4566
4567		/* --------------------------------- */
4568
4569		:- use_module(b_state_model_check, [b_check_valid_state/1]).
4570
4571		% note: set_up_initialisation for CBC checks does not use this predicate
4572		b_initialise_machine(ConstantsState,NormalisedInitialVarsState,FullInitialState,Path) :-
4573	?	if(b_initialise_machine2(ConstantsState,NormalisedInitialVarsState,FullInitialState,Path),
4574		true,
4575		(\+ logged_error(initialisation_fails,_,_,_), % we have already provided a more precise error message
4576		\+ abort_error_exists_in_context_state(initialisation_fails), % ditto as a state error
4577		(bmachine:b_machine_temp_predicate(TempPred)
4578		-> add_message(initialisation_fails,'INITIALISATION FAILS with provided predicate: ',TempPred,TempPred)
4579		; b_get_initialisation_from_machine(Stmt,_OType)
4580		-> add_error(initialisation_fails,'INITIALISATION FAILS','',Stmt)
4581		; add_error(initialisation_fails,'MACHINE has no INITIALISATION clause')
4582		),
4583		fail)
4584		).
4585
4586		b_initialise_machine2(ConstantsState,NormalisedInitialVarsState,FullInitialState,Path) :-
4587		/* InitialVarsState is an ouput */
4588		b_get_initialisation_from_machine(InitStatement,OType),
4589		( InitStatement=[] ->
4590		Path = [],
4591		add_message(b_initialise_machine,'Machine has no INITIALISATION statement(s)!'),
4592		NormalisedInitialVarsState = [],
4593		FullInitialState = ConstantsState
4594		; OType == classic ->
4595		Path = [path(PathInfo)],
4596		b_get_machine_variables(DeclaredVars),
4597		set_up_undefined_localstate(DeclaredVars,ConstantsState,NewInState),
4598		/* this is if the INITIALISATION has a sequential composition; to avoid error messages */
4599		get_texpr_info(InitStatement,PosInfo),
4600		init_wait_flags_with_call_stack(WF,[operation_call('INITIALISATION',[],PosInfo)]),
4601		(bmachine:b_machine_temp_predicate(_)
4602		-> InitStatement2=InitStatement /* avoid enumerating each init statement in parallel in case additional guard links them */
4603		; translate_init_statements(InitStatement,InitStatement2)
4604		),
4605		check_additional_guard(true,InitialVarsState,ConstantsState,WF),
4606	?	b_execute_statement(InitStatement2,[],NewInState,InitialVarsState,WF,PathInfo),
4607		% Warning: in Z mode (e.g. test 565) the variable skeleton may not yet be set up !
4608		sort_variable_binding(InitialVarsState,NormalisedInitialVarsState),
4609		append(NormalisedInitialVarsState,ConstantsState,FullInitialState), % put constants at end to make sharing of complete tail-list easier for successor states; should be compatible with order in expand_const_and_vars
4610		split_names_and_types(DeclaredVars,DeclaredNames,DeclaredTypes),
4611	?	ground_wait_flags(WF),
4612
4613		b_enumerate_values_in_store(DeclaredNames,DeclaredTypes,_,InitialVarsState,WF) %% MOVED HERE TO AVOID that target values are enumerated before initialisation effect computed
4614		; OType = eventb_operation(_ChangeSet,ParaValues,_Operation) ->
4615		prepare_eventb_initialisation(ConstantsState,InitialVarsUnNormState,FullInitialUnNormState),
4616		get_texpr_expr(InitStatement,
4617		rlevent(_Name,_Sec,_Stat,Parameters,_Grd,_Thm,_Act,_VWit,_PWit,_Unmod,_AbsEv)),
4618	?	b_execute_event('initialisation',InitStatement,Parameters,ParaValues,ConstantsState,FullInitialUnNormState,Path),
4619		normalise_store(InitialVarsUnNormState,NormalisedInitialVarsState),
4620		normalise_store(FullInitialUnNormState,FullInitialState) % a bit of redundant work here; we do the work twice and try to normalise constants again !
4621		),
4622		b_check_valid_state(FullInitialState).
4623
4624		% ensure that the variables always appear in the same order as reported by b_get_machine_variables:
4625		% this is important for e.g., state_packing TO DO: we could sort them according to the variable names, but would there be a gain ??
4626		sort_variable_binding(Store,SortedStore) :- %print(sort_variable_binding(Store,SortedStore)),nl,
4627		b_get_machine_variables(Variables),
4628		sort_aux(Variables,Store,[],SortedStore).
4629		sort_aux([],S,Acc,NormRes) :- reverse(Acc,Res),
4630		normalise_store(Res,NormRes),
4631		(S=[] -> true ; add_internal_error('Unknown variable bindings: ',S)).
4632		sort_aux([TVar|T],Store,Acc,Res) :- def_get_texpr_id(TVar,ID),
4633		bselect(ID,Val,Store,Rest),
4634		sort_aux(T,Rest,[bind(ID,Val)|Acc],Res).
4635
4636		:- block bselect(?,?,-,?). % in Z mode (e.g. test 565) the variable skeleton may not yet be set up !
4637		bselect(ID,Val,[bind(ID1,Val1)|T],Rest) :- % we assume ID1 is nonvar
4638		(ID=ID1 -> Val=Val1,T=Rest
4639		; Rest = [bind(ID1,Val1)|RT],
4640		bselect(ID,Val,T,RT)).
4641
4642		prepare_eventb_initialisation(ConstantsState,InitialVarsState,FullInitialState) :-
4643		b_get_machine_variables(Variables),
4644		empty_state(Empty),
4645		set_up_typed_localstate(Variables,_,_,Empty,InitialVarsState,positive),
4646		% NormalisedInitialVarsState = InitialVarsState, % TO DO : check that b_event normalises this
4647		combine_updates(InitialVarsState,ConstantsState,FullInitialState).
4648		% put constants at end, to be compatible with b_initialise_machine2 and expand_const_and_vars order and e.g. ltsmin
4649
4650
4651
4652		reset_b_interpreter :-
4653		%reset_partial_evaluator,
4654		retractall(project_properties_on_identifiers(_)),
4655		reset_unsat_component_infos,
4656		retractall(no_solution_found_for_constants).
4657
4658		:- use_module(eventhandling,[register_event_listener/3]).
4659		:- register_event_listener(clear_specification,reset_b_interpreter,
4660		'Reset B-Interpreter Memo Table & Unsat Components.').