1		% (c) 2009-2026 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,[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,BitSetMask)), % Note: when we assert this we checked that invariant holds in predecessor state
150		intersect_invs(BitSetMask,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		:- use_module(probsrc(bit_sets),[member_bitset/2]).
160		intersect_invs(invariant_preserved,Inv) :- !, Inv= b(truth,pred,[]).
161		intersect_invs(Mask,InvList) :- integer(Mask), !,
162		findall(nth1_invariant(Nr), member_bitset(Nr,Mask), InvList).
163		intersect_invs(M,Inv) :- !, add_internal_error('Illegal empty specialized inv list:', intersect_invs(M,Inv)),
164		Inv = b(falsity,pred,[]).
165
166
167		/* ----------------------------------*/
168
169		:- load_files(library(system), [when(compile_time), imports([environ/2])]).
170
171
172		state_satisfies_invariant_aux(ID,State) :-
173		check_invariant_with_time_out(ID,State). % version without partial evaluation
174
175
176		:- use_module(library(timeout)).
177
178		:- use_module(tools_printing,[format_with_colour_nl/4]).
179		:- use_module(probsrc(specfile),[prepare_state_for_specfile_trans/3]).
180		% called by prob_cli when invariant violation found:
181		% we no longer have access to the specialized_inv facts
182		analyse_invariant_for_state(ID) :-
183		b_invariant_number_list(InvList),
184		visited_expression(ID,State),
185		prepare_state_for_specfile_trans(State,ID,PreparedCurState),
186		maplist(check_invariant(ID,PreparedCurState),InvList).
187		check_invariant(ID,State,InvariantNr) :-
188		enter_new_error_scope(L,check_invariant),
189		check_invariant_predicate_with_time_out_res(InvariantNr,State,TimeOutRes),
190		(TimeOutRes=success -> true
191		; InvariantNr = nth1_invariant(Nr),
192		b_nth1_invariant(Nr,Invariant,_UsedIds),
193		translate_bexpression_with_limit(Invariant,TS),
194		translate_span(Invariant,SpanStr),
195		(TimeOutRes=failure -> InvRes=false ; InvRes=unknown),
196		format_with_colour_nl(user_output,[red,bold],
197		'*** Invariant ~w ~w is ~w (in state with id ~w):~n ~w',[Nr,SpanStr,InvRes,ID,TS]),
198		% add_message(check_invariant,'Invariant false: ',Nr,TS),
199		(debug_mode(off) -> true
200		; translate:print_bstate(State),nl
201		)
202		% TODO: pass check dot_file_prefix or similar to analyse_invariant_for_state and call:
203		% bvisual:get_tree_from_expr(Tree, Invariant, [], State),
204		% bvisual:write_dot_graph_to_file(Tree,'invariant.dot')
205		), exit_error_scope(L,_ErrOcc,check_invariant).
206
207
208
209		check_invariant_with_time_out(ID,State) :-
210		%b_get_invariant_from_machine(Invariant),
211		b_invariant_number_list(InvList), % ensures operation caching can be applied
212		% TO DO: we could just get unproven invariants; unless we are in an initial state
213		check_invariant_predicate_with_time_out(ID,InvList,State).
214
215
216		check_invariant_predicate_with_time_out(ID,Invariant,State) :-
217		(check_invariant_predicate_with_time_out_res(Invariant,State,TimeOutRes)
218		-> check_time_out_res(TimeOutRes,ID)).
219
220		check_invariant_predicate_with_time_out_res(b(truth,_,_),_State,TimeOutRes) :- !, % only typing in invariant
221		TimeOutRes = success.
222		check_invariant_predicate_with_time_out_res(Invariant,State,TimeOutRes) :-
223		set_error_context(checking_invariant),
224		preferences:get_computed_preference(debug_time_out,DebugTimeOut),
225		call_cleanup(
226		(time_out_with_enum_warning_one_solution_no_new_error_scope(
227		b_interpreter:check_invariant_predicate_aux(Invariant,State ),
228		DebugTimeOut,TimeOutRes)
229		-> true
230		; TimeOutRes = failure),
231		clear_error_context).
232
233		% process typed predicates, lists and special invariant(Nr) terms
234		check_invariant_predicate_aux(nth1_invariant(Nr),State) :- !,
235		((get_preference(operation_reuse_setting,false) ;
236		get_preference(try_operation_reuse_for_invariants,false))
237	?	-> check_nth1_invariant(Nr,State)
238	?	; \+ b_operation_cache:check_invariant_violated_cache(Nr,State) % will call check_nth1_invariant if necessary
239		% note : for performance it is important that the State is prepared but not expanded
240		% (e.g. it should be expanded_const_and_vars with the info field containing the packed state)
241		).
242		check_invariant_predicate_aux([],_) :- !.
243		check_invariant_predicate_aux([H|T],State) :- !,
244	?	check_invariant_predicate_aux(H,State),
245	?	check_invariant_predicate_aux(T,State).
246		check_invariant_predicate_aux(Invariant,State) :-
247		b_test_boolean_expression_for_ground_state(Invariant,[],State,'INVARIANT',0).
248
249		% check the nth invariant
250		check_nth1_invariant(Nr,State) :-
251		if(b_nth1_invariant(Nr,Invariant,_UsedIds),
252	?	b_test_boolean_expression_for_ground_state(Invariant,[],State,'INVARIANT',Nr), % add Nr to call_stack
253		add_internal_error('Invariant does not exist:',Nr)).
254
255
256		check_time_out_res(time_out,ID) :- !,
257		format('**** TIMEOUT during invariant evaluation in state ~w!~n',[ID]),
258		assert_time_out_for_invariant(ID),
259		fail.
260		check_time_out_res(virtual_time_out(_WARNING),ID) :- !,
261		format('**** VIRTUAL TIMEOUT during invariant evaluation in state ~w!~n',[ID]),
262		assert_time_out_for_invariant(ID),
263		fail.
264		check_time_out_res(failure,_) :- !, fail.
265		check_time_out_res(_,_).
266
267		% b_test_boolean_expression_for_ground_state:
268		% idea: check each conjunct individually; avoids multiplication of choice points between conjuncts
269
270		:- use_module(specfile,[expand_const_and_vars_to_full_store/2]).
271		b_test_boolean_expression_for_ground_state(b(Expr,_,Infos),LS,S,PredKind) :-
272	?	b_test_boolean_expression_for_ground_state(b(Expr,_,Infos),LS,S,PredKind,0).
273		b_test_boolean_expression_for_ground_state(b(Expr,_,Infos),LS,S,PredKind,Nr) :-
274		expand_const_and_vars_to_full_store(S,FS), % ensure we have full store
275	?	b_test_boolean_expression_for_ground_state2(Expr,Infos,LS,FS,PredKind,Nr).
276
277		b_test_boolean_expression_for_ground_state1(b(Expr,_,Infos),LS,S,Kind,Nr) :- !,
278	?	b_test_boolean_expression_for_ground_state2(Expr,Infos,LS,S,Kind,Nr).
279
280		b_test_boolean_expression_for_ground_state2(conjunct(LHS,RHS),_,LocalState,State,Kind,Nr) :- !,
281		% usually LHS is the nested conjunct and RHS atomic:
282		%it would be better to swap LHS and RHS: but does not seem to buy anything
283	?	b_test_boolean_expression_for_ground_state1(LHS,LocalState,State,Kind,Nr),
284		!, % do we need this cut; it makes partial evaluation more tricky
285	?	b_test_boolean_expression_for_ground_state1(RHS,LocalState,State,Kind,Nr).
286		% TO DO: treate lazy_let_pred ?
287		b_test_boolean_expression_for_ground_state2(BE,Infos,LS,S,Kind,Nr) :-
288	?	b_test_boolean_expression_cs(b(BE,pred,Infos),LS,S,Kind,Nr).
289
290		state_violates_invariant(ID,State) :-
291		State \== root,
292		State \= concrete_constants(_), % machine not yet initialised (cf state_corresponds_to_initialised_b_machine)
293		\+(state_satisfies_invariant_aux(ID,State)).
294
295
296		% new profiler
297		%:- use_module('../extensions/profiler/profiler.pl').
298		%:- use_module('../extensions/profiler/profiler_te.pl').
299		%:- enable_profiling_naming(b_interpreter:state_violates_assertions_aux/2,name2).
300
301		%name2(b_interpreter:state_violates_assertions_aux,_,ASSERTIONS).
302
303		%state_violates_assertions(ID,State) :-
304		% b_interpreter:state_violates_assertions_aux(ID,State).
305
306		:- use_module(bmachine,[get_assertions_from_machine/2, b_machine_has_dynamic_assertions/0, b_machine_has_static_assertions/0]).
307		state_violates_assertions(ID,State) :-
308		profile_single_call('ASSERTIONS',ID,b_interpreter:state_violates_assertions_aux(ID,State)).
309		state_violates_assertions_aux(ID,State) :-
310		b_machine_has_dynamic_assertions,
311		state_corresponds_to_initialised_b_machine(State,BState), !,
312		\+(state_satisfies_assertions(ID,dynamic,BState)).
313		state_violates_assertions_aux(ID,State) :-
314		b_machine_has_static_assertions,
315		state_corresponds_to_set_up_constants_only(State,BState),
316		\+(state_satisfies_assertions(ID,static,BState)).
317		state_satisfies_assertions(ID,Type,State) :-
318		( get_assertions_from_machine(Type,Ass) ->
319		set_error_context(checking_assertions),
320		%enter_new_error_scope(Level,checking_assertions),
321		preferences:get_computed_preference(debug_time_out,DebugTimeOut),
322		%print(checking_assertions(ID)),nl,
323		time_out_with_enum_warning_one_solution(
324		b_test_list_of_boolean_expression_for_ground_state(Ass,'ASSERTION ',[],State),
325		DebugTimeOut,TimeOutRes, clear_errors),
326		% 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
327		clear_error_context,
328		(nonvar(TimeOutRes),
329		(TimeOutRes == time_out, Kind='TIMEOUT' ; TimeOutRes = virtual_time_out(_), Kind = 'Virtual TIMEOUT')
330		-> format('~n*** ~w during assertion checking for state id ~w!~n',[Kind,ID]),
331		assert_time_out_for_assertions(ID)
332		; true
333		)
334		; true
335		).
336
337
338
339		/* ----------------------------------*/
340		/* b_test_boolean_expression */
341		/* ----------------------------------*/
342
343
344		:- type variable_id_list +--> list(type(variable_id)).
345
346		:- type boolean_expression +--> call(bsyntaxtree:check_if_typed_predicate).
347
348		% used for testing ASSERTIONS on a fully ground state
349		b_test_list_of_boolean_expression_for_ground_state(List,PredKind,LS,S) :-
350		b_test_list_of_boolean_expression_aux(List,PredKind,1,LS,S).
351
352		b_test_list_of_boolean_expression_aux([],_,_,_,_).
353		b_test_list_of_boolean_expression_aux([B1|T],PredKind,Nr,LS,S) :- %nl,print(nr(PredKind,Nr)),nl,
354	?	(b_test_boolean_expression_for_ground_state1(B1,LS,S,PredKind,Nr)
355		-> N1 is Nr+1, b_test_list_of_boolean_expression_aux(T,PredKind,N1,LS,S)
356		; silent_mode(off),
357		(critical_enumeration_warning_occured_in_error_scope -> Res='UNKNOWN'
358		; abort_error_occured_in_error_scope -> Res ='NOT-WELL-DEFINED'
359		; Res='false'),
360		ajoin([PredKind, Nr, ' is ', Res,': '],Msg),
361		add_message(b_interpreter,Msg,B1,B1), % TO DO: get just label/location?
362		fail).
363
364
365		:- use_module(b_interpreter_components).
366
367
368		:- assert_pre(b_interpreter:b_test_boolean_expression_cs(E,LS,S,_,_),
369		(bsyntaxtree:check_if_typed_predicate(E),type_check(LS,store),type_check(S,store) )).
370		:- assert_post(b_interpreter:b_test_boolean_expression_cs(_,_,_,_,_), true ).
371
372
373		% --------------------- BOOLEAN EXPRESSIONS ----------------------------
374
375		:- use_module(b_interpreter_check).
376		:- use_module(kernel_propagation, [do_not_enumerate_binary_boolean_operator/3]).
377
378		% a version where we can provide an initial call stack entry for context
379		b_test_boolean_expression_cs(E,LS,S,PredKind,Nr) :-
380		init_wait_flags_cs(E,PredKind,Nr,b_test_boolean_expression_cs,WF),
381		% TO DO: call b_trace_test_components ?
382	?	b_test_boolean_expression(E,LS,S,WF),
383	?	ground_wait_flags(WF).
384
385		init_wait_flags_cs(E,PredKind,Nr,PP,WF) :-
386		(PredKind=none -> init_wait_flags(WF,[PP])
387		; get_texpr_pos(E,Pos),
388		CallStackEntry = prob_command_context(check_pred_command(PredKind,Nr),Pos),
389		init_wait_flags_and_push_call_stack(no_wf_available,CallStackEntry,WF)
390		).
391
392
393		b_test_boolean_expression(b(Expr,_,Infos),LS,S,WF) :- !,
394		(b_interpreter_check:composed(Expr) -> empty_avl(Ai)
395		; Ai = no_avl), % simple expression: no sharing is possible: no need to register expressions
396	?	b_test_boolean_expression2(Expr,Infos,LS,S,WF,Ai,_).
397		b_test_boolean_expression(E,LS,S,WF) :- % will generate error message
398		empty_avl(Ai), b_test_boolean_expression(E,LS,S,WF,Ai,_).
399
400		:- assert_pre(b_interpreter:b_test_boolean_expression(E,LS,S,WF),
401		(nonvar(E),bsyntaxtree:check_if_typed_predicate(E),type_check(LS,store),type_check(S,store),
402		type_check(WF,wait_flag))).
403		:- assert_post(b_interpreter:b_test_boolean_expression(_,_,_,WF), type_check(WF,wait_flag)).
404
405
406		%b_test_boolean_expression(Expr,_,_,_) :- print('test: '),translate:print_bexpr(Expr),nl,print(Expr),nl,fail. %%
407
408		:- load_files(library(system), [when(compile_time), imports([environ/2])]).
409		:- if(environ(prob_debug_watch_flag,true)).
410		b_test_boolean_expressiond(b(Expr,_,Infos),LS,S,WF,Ai,Ao) :- !,
411		b_test_boolean_expression2(Expr,Infos,LS,S,WF,Ai,Ao).
412		b_test_boolean_expression(Expr,LS,S,WF,Ai,Ao) :- !,
413		(waitflag0_is_set(WF)
414		-> debug:watch(300,b_interpreter:b_test_boolean_expressiond(Expr,LS,S,WF,Ai,Ao))
415		; debug:watch_det(300,b_interpreter:b_test_boolean_expressiond(Expr,LS,S,WF,Ai,Ao)) ).
416		:- else.
417		b_test_boolean_expression(b(Expr,Type,Infos),LS,S,WF,Ai,Ao) :- !,
418		(preference(smt_supported_interpreter,true)
419	?	-> b_test_boolean_expression2(Expr,Infos,LS,S,WF,Ai,Ao),
420		get_wait_flag1(smt_call,WF,BeforeEnumWF),
421		gensym:gensym(smt_assertion_name,Symbol),
422		smt_add_predicate(BeforeEnumWF,b(Expr,Type,Infos),LS,S,Symbol)
423		;
424	?	b_test_boolean_expression2(Expr,Infos,LS,S,WF,Ai,Ao)).
425		:- endif.
426		b_test_boolean_expression(E,LS,S,WF,Ai,Ao) :-
427		add_internal_error('Boolean expression not properly wrapped: ',
428		b_test_boolean_expression(E,LS,S,WF,Ai,Ao)),
429		b_test_boolean_expression2(E,[],LS,S,WF,Ai,Ao).
430
431
432		b_test_boolean_expression2(truth,_,_,_,_WF,Ai,Ao) :- !,Ai=Ao.
433		b_test_boolean_expression2(falsity,_,_,_,_WF,_Ai,_Ao) :- !,fail.
434		b_test_boolean_expression2(negation(BExpr),_,LocalState,State,WF,Ai,Ao) :- !,
435	?	b_not_test_boolean_expression(BExpr,LocalState,State,WF,Ai,Ao).
436		b_test_boolean_expression2(conjunct(LHS,RHS),_,LocalState,State,WF,Ai,Ao) :- !,
437	?	b_test_boolean_expression(LHS,LocalState,State,WF,Ai,Aii),
438	?	b_test_boolean_expression(RHS,LocalState,State,WF,Aii,Ao).
439		b_test_boolean_expression2(implication(LHS,RHS),Info,LocalState,State,WF,Ai,Ao) :-
440		%b_compiler:b_compile(LHS,[],LocalState,State,CLHS), % this slows down Cruise benchmark from 3.75 s to 4.3
441		!,
442	?	b_test_implication(LHS,RHS,Info,LocalState,State,WF,Ai,Ao).
443		b_test_boolean_expression2(equivalence(LHS,RHS),_,LocalState,State,WF,Ai,Ao) :- !,
444	?	b_test_equivalence(LHS,RHS,LocalState,State,WF,Ai,Ao).
445		b_test_boolean_expression2(disjunct(LHS,RHS),Info,LocalState,State,WF,Ai,Ao) :- !,
446		% TO DO: normalise disjunct first ?
447		copy_wf_start(WF,disjunct,CWF),
448	?	if(b_check_boolean_expression(LHS,LocalState,State,CWF,PredRes,Ai,Aii),
449		% we can check lhs
450	?	if(b_interpreter_check:b_check_boolean_expression0(pred_false,PredRes,RHS,LocalState,State,CWF,RR,Aii,Ao),
451		( /* we can also check rhs */
452	?	b_interpreter_check:disjoin(PredRes,RR,pred_true,LHS,RHS,WF),
453		copy_wf_finish(WF,CWF)
454		),
455		(
456		Ao=Aii,
457		copy_wf_finish(WF,CWF),
458		imply_test_boolean_expression(PredRes,pred_false,RHS,LocalState,State,WF,Aii),
459		perfmessagecall(choice_point,reification_of_disjunction_rhs_failed,translate:print_bexpr(RHS),Info),
460		enumerate_bool(PredRes,15,WF)
461		)
462		),
463		% we cannot check lhs
464		if((always_well_defined(RHS),
465		b_check_boolean_expression(RHS,LocalState,State,CWF,PredRes,Ai,Aii)),
466		(
467		Ao=Aii,
468		copy_wf_finish(WF,CWF),
469		imply_test_boolean_expression(PredRes,pred_false,LHS,LocalState,State,WF,Aii),
470		perfmessagecall(choice_point,reification_of_disjunction_lhs_failed,translate:print_bexpr(LHS),Info),
471		enumerate_bool(PredRes,15,WF)
472		),
473		% we cannot check neither lhs nor rhs:
474		(Ai=Ao,
475		get_priority_of_boolean_expression2(disjunct(LHS,RHS),StartPrio),
476		%get_wait_flag(Prio,disjunct,WF,WF2),
477		get_binary_choice_wait_flag_exp_backoff(StartPrio,disjunct,WF,WF2),
478		% be sure that e.g. for (x=2 or x=3) both branches will be tested once deterministic propagation is over
479		%print(prio(Prio)), print(' : '),print_bexpr(LHS), print(' or '), print_bexpr(RHS),nl,
480		perfmessagecall(choice_point,reification_of_disjunction_failed,translate:print_bexpr(b(disjunct(LHS,RHS),pred,Info)),Info),
481		b_test_disjunction(LHS,RHS,LocalState,State,WF,WF2,Ai)
482		)
483		)
484		).
485		b_test_boolean_expression2(exists(Parameters,RHS),Infos,LocalState,State,WF,Ai,Ao) :- !,Ai=Ao,
486	?	b_test_exists(Parameters,RHS,Infos,LocalState,State,WF).
487		%b_test_boolean_expression2(forall(PARS,LHS,RHS),_Inf,LocalState,State,WF) :-
488		% PARS = [b(identifier(R1),integer,_),b(identifier(R2),integer,_)],
489		% LHS = b(conjunct(b(conjunct(MEM1,MEM2),pred,_I1),NEQ),pred,_I2),
490		% NEQ = b(not_equal(b(identifier(RR1),integer,_I3),b(identifier(RR2),integer,_I4)),pred,_I5),
491		% (RR1=R1, RR2=R2 ; RR1=R2, RR2=R1),
492		% MEM1 = b(member(b(identifier(RRR1),integer,_),b(SET,set(integer),_)),pred,_),
493		% MEM2 = b(member(b(identifier(RRR2),integer,_),b(SET,set(integer),_)),pred,_),
494		% (RRR1=R1, RRR2=R2 ; RRR1=R2, RRR2=R1),
495		% /* TO DO: check that RHS is symmetric ! */ /* TO DO : generalize symmetry breaking */
496		% !, % print(symmetry_breaking_forall(R1,R2)),nl,
497		% GT = b(less(b(identifier(R1),integer,_I3),b(identifier(R2),integer,_I4)),pred,_I5),
498		% NewLHS = b(conjunct(b(conjunct(MEM1,MEM2),pred,_I1),GT),pred,_I2),
499		% b_test_boolean_expression2(forall(PARS,NewLHS,RHS),_Inf,LocalState,State,WF).
500		b_test_boolean_expression2(forall(Parameters,LHS,RHS),Infos,LocalState,State,WF,Ai,Ao) :- !,Ai=Ao,
501		/* !ID.(LHS => RHS) */
502	?	b_for_all(Parameters,Infos,LHS,RHS,LocalState,State,WF).
503		b_test_boolean_expression2(let_predicate(Ids,AssignmentExprs,Pred),Infos,LocalState,State,WF,Ai,Ao) :- !,
504		Ai=Ao, % any expression inside the LET cannot be safely reused
505		(is_truth(Pred)
506		-> % useless let, only sense of computations below is in detecting WD errors
507		get_enumeration_starting_wait_flag(useless_let_predicate(Ids),WF,ESWF),
508		when(nonvar(ESWF),set_up_localstate_for_let(Ids,_,AssignmentExprs,LocalState,State,_LetState,WF))
509	?	; set_up_localstate_for_let(Ids,ParaValues,AssignmentExprs,LocalState,State,LetState,WF),
510		opt_push_wait_flag_call_stack_quantifier_info(WF,let_quantifier,Ids,ParaValues,Infos,WF2),
511	?	b_test_boolean_expression(Pred,LetState,State,WF2)). % we could pass Ai in if Ids fresh
512
513		b_test_boolean_expression2(lazy_let_pred(Id,AssignmentExpr,Expr),_I,LocalState,State,WF,Ai,Ao) :- !,
514		add_lazy_let_id_and_expression(Id,AssignmentExpr,LocalState,State,NewLocalState,WF,Ai),
515	?	b_test_boolean_expression(Expr,NewLocalState,State,WF,Ai,Ao).
516		% we could use Ai,Ao version as lazy lets never interfere with each other and never invalidate existing expressions
517		b_test_boolean_expression2(lazy_lookup_pred(Id),_Info,LocalState,_State,WF,Ai,Ao) :- !, Ai=Ao,
518		lookup_value_for_existing_id_wf(Id,LocalState,(Trigger,Value),WF),
519		% should normally only occur in LocalState; value introduced by lazy_let
520		(Trigger,Value) = (pred_true,pred_true). % force evaluation
521		b_test_boolean_expression2(value(PredVal),_Info,_LocalState,_State,_WF,Ai,Ao) :- !,
522		% this can occur when lazy_lookup_pred gets compiled by b_compiler
523		is_pred_true(PredVal),Ai=Ao.
524		b_test_boolean_expression2(Pred,Info,LocalState,State,WF,Ai,Ao) :-
525		% TO DO: we could put some of the operators into the Ai store (comparison operators)
526	?	b_interpreter_check:register_predicate(Pred,Info,pred_true,Reused,Ai,Ao),
527		(Reused==true
528		-> %% print('REUSED: '), translate:print_bexpr(Pred),nl
529		true
530	?	; b_test_atomic_boolean_expression2(Pred,Info,LocalState,State,WF)).
531
532		:- block is_pred_true(-).
533		is_pred_true(X) :- (X=pred_true -> true ; X=pred_false -> fail ; add_internal_error('Illegal call: ',is_pred_true(X)),fail).
534		:- block is_pred_false(-).
535		is_pred_false(X) :- (X=pred_false -> true ; X=pred_true -> fail ; add_internal_error('Illegal call: ',is_pred_false(X)),fail).
536
537
538		% we could simply call disjunct(NegLHS,RHS) ?
539		% A => B has more of a feeling of a passive constraint than A or B
540		% hence we use a lower priority here for enumerate_bool below and do not
541		% try to reify rhs if lhs reification failed (but maybe we should)
542		b_test_implication(LHS,RHS,_Info,LocalState,State,WF,Ai,Ao) :-
543		copy_wf_start(WF,implication,CWF),
544	?	if(b_check_boolean_expression(LHS,LocalState,State,CWF,PredRes,Ai,Aii),
545		%% print('checking => '), print_bexpr(LHS), print(' '), print(PredRes),nl,
546		%% The following improves constraint propagation; but can be tricky with undefinedness
547		if((var(PredRes),always_well_defined(RHS),
548		b_check_boolean_expression(RHS,LocalState,State,CWF,RHSPredRes,Aii,Ao)),
549		(/* also propagate from right to left */
550	?	b_interpreter_check:imply_true(PredRes,RHSPredRes),
551		perfmessage_bexpr(good(reify),'Fully reified implication with LHS: ',LHS),
552	?	copy_wf_finish(WF,CWF)
553		),
554		( Aii=Ao,
555	?	copy_wf_finish(WF,CWF),
556	?	imply_test_boolean_expression(PredRes,pred_true,RHS,LocalState,State,WF,Aii),
557		(nonvar(PredRes) -> true
558		; performance_monitoring_on,
559		\+always_well_defined(RHS) -> perfmessage_bexpr(reify,'Cannot reify RHS of => due to WD condition, creating choice point:',RHS)
560		; perfmessage_bexpr(reify,'Cannot reify RHS of =>, creating choice point:',RHS)
561		),
562		enumerate_bool(PredRes,10000,WF) % lower priority than disjunction (15); we could use last_finite_priority ?
563		)
564		),
565		( Ai=Ao,
566		perfmessage_bexpr(reify,'Cannot reify LHS of =>, creating binary choice point:',LHS),
567		get_binary_choice_wait_flag(implication,WF,WF2),
568		block_test_implication(LHS,RHS,LocalState,State,WF,WF2)
569		)
570		).
571
572		% ------------
573
574		:- discontiguous b_test_atomic_boolean_expression2/5.
575		%b_test_atomic_boolean_expression2(Expr,T,LocalState,State,WF) :- print(eval(Expr,T)),nl,fail.
576		b_test_atomic_boolean_expression2(partition(LHS,RHS),_,LocalState,State,WF) :- !,
577		b_compute_expression(LHS,LocalState,State,SV1,WF), %print(lhs(SV1)),nl,
578		l_compute_expression(RHS,LocalState,State,SV2,WF), % RHS is Prolog list of expressions
579	?	kernel_call_predicate(partition_wf(SV1,SV2,WF),kernel_objects,WF,partition(LHS,RHS)).
580		b_test_atomic_boolean_expression2(member(TElem,TSet),_,LocalState,State,WF) :- !,
581	?	b_test_member_expression(TElem,TSet,LocalState,State,WF).
582		b_test_atomic_boolean_expression2(not_member(TElem,TSet),Info,LocalState,State,WF) :- !,
583		get_texpr_expr(TSet,Set),
584	?	b_test_notmember_expression(Set,TElem,TSet,Info,LocalState,State,WF).
585		b_test_atomic_boolean_expression2(freetype_case(Freetype,Case,Expr),_,LocalState,State,WF) :-
586		!,equal_object_wf(Value,freeval(Freetype,Case,_),b_test_atomic_boolean_expression2,WF),
587		b_compute_expression(Expr,LocalState,State,Value,WF). % NOT COVERED (16)
588		b_test_atomic_boolean_expression2(finite(SetExpr),_,LocalState,State,WF) :-
589		!, b_compute_expression(SetExpr,LocalState,State,Value,WF),
590		kernel_call_predicate(is_finite_set_wf(Value,WF),kernel_objects,WF,finite(SetExpr)).
591		/* Extension for Kodkod */
592		b_test_atomic_boolean_expression2(kodkod(ProblemId,_),_,LocalState,State,WF) :-
593		!,get_wait_flag1(kodkod_call,WF,WF0),
594		kodkod_request(ProblemId,pos,LocalState,State,WF0). % NOT COVERED (17)
595		%b_test_atomic_boolean_expression2(equal(Arg1,Arg2),_,LocalState,State,WF) :- get_texpr_type(Arg1,integer),!,
596		% b_compute_expression(Arg1,LocalState,State,ExprRes,WF),
597		% 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 */
598
599		:- include(b_arithmetic_expressions).
600		%The following clause improves Nqueens performance by about 50 %; by avoiding intermediate variables
601		% TO DO: do the same for >, <, >= ...
602		b_test_atomic_boolean_expression2(equal(Arg1,Arg2),Info,LocalState,State,WF) :- !,
603	?	b_test_atomic_equal_boolean_expression(Arg1,Arg2,Info,LocalState,State,WF).
604		b_test_atomic_boolean_expression2(not_equal(Arg1,Arg2),Info,LocalState,State,WF) :- !,
605	?	b_test_atomic_not_equal_boolean_expression(Arg1,Arg2,Info,LocalState,State,WF).
606		b_test_atomic_boolean_expression2(less_equal(Arg1,Arg2),_Info,LocalState,State,WF) :-
607		%get_texpr_type(Arg1,integer), % type checker already checks this
608		preferences:preference(use_clpfd_solver,true),
609		!,
610	?	b_compute_arith_expression(Arg1,LocalState,State,CLPFD_Expr1,WF),
611	?	b_compute_arith_expression(Arg2,LocalState,State,CLPFD_Expr2,WF),
612	?	clpfd_interface:clpfd_leq_expr(CLPFD_Expr1,CLPFD_Expr2).
613		b_test_atomic_boolean_expression2(greater_equal(Arg1,Arg2),_Info,LocalState,State,WF) :-
614		%get_texpr_type(Arg1,integer), % type checker already checks this
615		preferences:preference(use_clpfd_solver,true),
616		!,
617		b_compute_arith_expression(Arg1,LocalState,State,CLPFD_Expr1,WF),
618		b_compute_arith_expression(Arg2,LocalState,State,CLPFD_Expr2,WF),
619		clpfd_interface:clpfd_leq_expr(CLPFD_Expr2,CLPFD_Expr1).
620		b_test_atomic_boolean_expression2(less(Arg1,Arg2),_Info,LocalState,State,WF) :-
621		%get_texpr_type(Arg1,integer), % type checker already checks this
622		preferences:preference(use_clpfd_solver,true),
623		!,
624	?	b_compute_arith_expression(Arg1,LocalState,State,CLPFD_Expr1,WF),
625	?	b_compute_arith_expression(Arg2,LocalState,State,CLPFD_Expr2,WF),
626	?	clpfd_interface:clpfd_lt_expr(CLPFD_Expr1,CLPFD_Expr2).
627		b_test_atomic_boolean_expression2(greater(Arg1,Arg2),_Info,LocalState,State,WF) :-
628		%get_texpr_type(Arg1,integer), % type checker already checks this
629		preferences:preference(use_clpfd_solver,true),
630		!,
631	?	b_compute_arith_expression(Arg1,LocalState,State,CLPFD_Expr1,WF),
632		b_compute_arith_expression(Arg2,LocalState,State,CLPFD_Expr2,WF),
633		clpfd_interface:clpfd_lt_expr(CLPFD_Expr2,CLPFD_Expr1).
634		b_test_atomic_boolean_expression2(external_pred_call(FunName,Args),Info,LocalState,State,WF) :-
635		!,
636		(do_not_evaluate_args(FunName) -> EvaluatedArgs=[]
637	?	; b_compute_expressions(Args, LocalState,State, EvaluatedArgs, WF)),
638		push_wait_flag_call_stack_info(WF,external_call(FunName,EvaluatedArgs,Info),WF2),
639	?	call_external_predicate(FunName,Args,EvaluatedArgs,LocalState,State,pred_true,Info,WF2).
640		b_test_atomic_boolean_expression2(Expression,Info,LocalState,State,WF) :-
641		preferences:preference(use_clpfd_solver,false),
642		special_binary_predicate(Expression,Module:Kernel_predicate,Arg1,T1,Arg2,T2),
643		(nonmember(contains_wd_condition,Info) -> true ; preference(disprover_mode,true)),
644		!,
645		% print('Special call: '), print_bexpr(Expression),nl, print(Kernel_predicate),print(' : '),nl,
646		%(Arg1==list_of_expressions -> b_compute_expressions ... % no longer needed
647		b_compute_expression(Arg1,LocalState,State,SV1,WF),
648		b_compute_expression(Arg2,LocalState,State,SV2,WF),
649		KernelCall =.. [Kernel_predicate,SV1,T1,SV2,T2,WF],
650		kernel_call_predicate(KernelCall,Module,WF,Expression).
651		b_test_atomic_boolean_expression2(Expression,_,LocalState,State,WF) :-
652		functor(Expression,BOP,2),
653		kernel_mappings:binary_boolean_operator(BOP,Module:Kernel_predicate,WFEnabled),!,
654		arg(1,Expression,Arg1), arg(2,Expression,Arg2),
655	?	b_compute_expression(Arg1,LocalState,State,SV1,WF), % TODO: symbolic for some BOP: <:, <<: ?
656		(binary_boolean_operator_trivially_true(BOP,SV1)
657		-> check_well_defined(Arg2,LocalState,State,WF)
658	?	; b_compute_expression(Arg2,LocalState,State,SV2,WF),
659		( WFEnabled==yes ->
660		KernelCall =.. [Kernel_predicate,SV1,SV2,WF2],
661		(do_not_enumerate_binary_boolean_operator(BOP,Arg1,Arg2) % we assume: this is only true for WFEnabled predicates
662		-> add_wait_flag_info(WF,wfx_no_enumeration,WF2)
663		; WF2=WF)
664		; KernelCall =.. [Kernel_predicate,SV1,SV2], WF2=WF % note: WF2 still used in kernel_call_predicate
665		),
666	?	kernel_call_predicate(KernelCall,Module,WF2,Expression)
667		).
668		b_test_atomic_boolean_expression2(E,Info,_LS,_S,_WF) :-
669		add_internal_error('Uncovered boolean expression: ',b(E,pred,Info)),
670		print_functor(E),nl,
671		fail.
672
673
674		binary_boolean_operator_trivially_true(subset,X) :- X==[].
675
676		check_well_defined(Arg,_LocalState,_State,_WF) :-
677		always_well_defined(Arg),!.
678		check_well_defined(Arg,LocalState,State,WF) :-
679		b_compute_expression(Arg,LocalState,State,_,WF).
680
681		%:- use_module(specfile,[animation_minor_mode/1]).
682		:- use_module(b_machine_hierarchy,[abstract_constant/2, concrete_constant/2]).
683		b_test_atomic_equal_boolean_expression(Arg1,Arg2,_Info,LocalState,State,WF) :-
684		Arg1 = b(_,integer,_), preferences:preference(use_clpfd_solver,true),!,
685		(Arg2 = b(_,integer,_) -> true ; add_internal_error('Type error in AST, not wrapped integer: ',Arg2)),
686	?	b_test_arith_equal_boolean_expression(Arg1,Arg2,LocalState,State,WF).
687		b_test_atomic_equal_boolean_expression(Arg1,Arg2,Info,LocalState,State,WF) :-
688		Arg1 = b(_,real,_), use_clpfd_real_solver, do_not_double_check_solution,!,
689		(Arg2 = b(_,real,_) -> true ; add_internal_error('Type error in AST, not wrapped real: ',Arg2)),
690		b_test_real_arith_equal_boolean_expression(Arg1,Arg2,Info,LocalState,State,WF).
691		b_test_atomic_equal_boolean_expression(Arg1,Arg2,Info,LocalState,State,WF) :-
692	?	member(prob_annotation('LAMBDA-EQUALITY'),Info),
693		\+ simple_expression(Arg2),
694		is_lambda_result_id(Arg1), %get_texpr_id(Arg1,'_lambda_result_'), % ensure we have not renamed it to was_lambda_result ?
695		!, % this is an equality for the result of a lambda abstraction; only evaluate at the end
696		b_compute_expression(Arg1,LocalState,State,SV1,WF), % this is the lambda result identifier _lambda_result_
697		%get_enumeration_finished_wait_flag(WF,EWF),
698		%get_wait_flag(10000,lambda_result,WF,EWF),
699		% compute deterministic parts of Arg2 in wf0 phase: avoid computing this stuff over again
700		%print('DELAY: '), translate:print_bexpr(Arg2),nl,
701	?	kernel_waitflags:copy_wf01e_wait_flags(WF,WF2), b_compute_expression(Arg2,LocalState,State,SV2,WF2),
702		get_last_wait_flag(lambda_result,WF,EWF),
703		ground_value_check(SV2,G2),
704	?	when((nonvar(G2);nonvar(SV1);nonvar(EWF)),b_lambda_result_equal_boolean_expression(SV1,SV2,WF,EWF,WF2)).
705		b_test_atomic_equal_boolean_expression(Arg1,Arg2,Info,LocalState,State,WF) :-
706		(LocalState = []
707		-> true % only check if we are at the outer level
708		% (not inside a quantifier,...) or if we have CSE introduzed lazy_lets:
709		; preferences:preference(use_common_subexpression_elimination,true)
710		% TO DO: check that we have only added @nr to local state from lazy_let; ADD INFO FIELD
711		),
712		get_texpr_type(Arg1,Type1), is_set_type(Type1,SetType1),
713		% previously we required SetType1 = couple(_,_)
714		get_texpr_id(Arg1,ID),
715		% we could check: \+ get_texpr_id(Arg2,_), we do not need to treat simple equations like ID=ID2; unless for memo?
716	?	(abstract_constant(ID,_) % check if ABSTRACT_CONSTANT
717		-> Kind=abstract,
718	?	kernel_objects:max_cardinality(Type1,MaxCard1),
719		(number(MaxCard1) % check that type is large enough to warrant recursive or symbolic treatment
720		-> (MaxCard1>100 -> true ; constant_variable_marked_as_memo(ID))
721		; true)
722		; %fail,
723	?	concrete_constant(ID,_)
724		-> Kind=concrete,
725		(constant_variable_marked_as_expand(ID)
726		-> true % note: we also check for expand annotation in store (expand_closure_value),
727		% but it is useful to expand ID already here to ease checking PROPERTIES
728		; constant_variable_marked_as_memo(ID))
729		%; b_is_unused_constant(ID) -> ABSTRACT=true % TO DO: check if ID not used somewhere else in Properties ??!!
730		),
731		% in future: we may do size change analysis, or something like that to check that we have properly defined
732		% recursive function
733		debug_format(19,'Equation defining ~w constant: ~w~n',[Kind,ID]),
734		!,
735		(constant_variable_marked_as_expand(ID) -> SymArg2 = Arg2 ; mark_bexpr_as_symbolic(Arg2,SymArg2)),
736	?	b_add_constant_definition(Kind,ID,Info,Arg1,SetType1,SymArg2,LocalState,State,WF).
737		b_test_atomic_equal_boolean_expression(Arg1,Arg2,Info,LocalState,State,WF) :-
738		constants_profiling_on,
739		get_texpr_id(Arg1,ID),b_is_constant(ID), !,
740		% Note: does not yet keep track of arithmetic equalities above
741		b_compute_expression(Arg1,LocalState,State,SV1,WF),
742		push_constant_def_equality_call_stack(WF,ID,Info,WF2),
743		start_profile(ID,T1),
744		b_compute_expression(Arg2,LocalState,State,SV2,WF2),
745		get_waitflags_phase(WF,Phase),
746		stop_constant_profile(SV2,Phase,ID,[],T1), % normal constant, not symbolic, memoized or recursive
747		start_propagation_profile(ID,T2,CstL1),
748		kernel_call_predicate_equal_object_optimized(SV1,SV2,WF),
749		stop_propagation_profile(SV2,ID,T2,CstL1).
750		b_test_atomic_equal_boolean_expression(Arg1,Arg2,_Info,LocalState,State,WF) :-
751	?	b_compute_expression(Arg1,LocalState,State,SV1,WF),
752	?	b_compute_expression(Arg2,LocalState,State,SV2,WF),
753	?	kernel_call_predicate_equal_object_optimized(SV1,SV2,WF).
754
755
756
757		% treat equality ID = Symbolic Function (or relation/set)
758		b_add_constant_definition(Kind,ID,Info,Arg1,SetType1,SymArg2,LocalState,State,WF) :-
759		% observe CTRL-C: e.g., in data validation models these abstract functions can be very large and costly to compute
760	?	observe_user_interrupt_signal(computing_value_for_abstract_constant(ID),SymArg2,
761		b_add_constant_definition_aux(Kind,ID,Info,Arg1,SetType1,SymArg2,LocalState,State,WF)).
762
763		:- use_module(runtime_profiler,[start_profile/2,
764		stop_constant_profile/5, constants_profiling_on/0]).
765		b_add_constant_definition_aux(Kind,ID,_Info,Arg1,SetType1,SymArg2,LocalState,State,WF) :-
766		preference(use_function_memoization,MemoPref), % true, false or default
767		MemoPref \= false, % turned off
768		( MemoPref = true, Kind=abstract ;
769		constant_variable_marked_as_memo(ID)), % description(memo) as info field using @desc memo pragma; see
770		!,
771		start_profile(ID,T1),
772		b_compute_expression(Arg1,LocalState,State,SV1,WF), % the identifier
773		(SymArg2 = b(recursive_let(TID,Body),_,_)
774		-> get_texpr_id(TID,RecID),
775		b_compute_expression(Body,[bind(RecID,RedIDVal)|LocalState],State,SV2,WF),
776		RecValue='$recursion_value'(RedIDVal), IDInfo = [recursive_memo]
777		; b_compute_expression(SymArg2,LocalState,State,SV2,WF),
778		RecValue='$no_recursion', IDInfo = [memoized]
779		),
780		get_waitflags_phase(WF,Phase), stop_constant_profile(SV2,Phase,ID,IDInfo,T1),
781		(nonvar(SV2), SV2 \= closure(_,_,_)
782		-> % value fully computed; no need to memoize
783		debug_println(19,not_memoizing(ID)),
784		kernel_call_predicate_equal_object_optimized(SV1,SV2,WF)
785		; (nonvar(SV2) -> mark_closure_as_symbolic(SV2,SV3) ; SV3=SV2),
786		memoization:register_memoization_function(ID,SV3,SetType1,RecValue,MEMOID,SV4),
787		debug_println(19,marking_for_memoization(ID,MEMOID)),
788		kernel_call_predicate_equal_object_optimized(SV1,SV4,WF)
789		).
790		b_add_constant_definition_aux(_Kind,ID,Info,Arg1,_,SymArg2,LocalState,State,WF) :-
791		start_profile(ID,T1),
792		b_compute_expression(Arg1,LocalState,State,SV1,WF), % the identifier ID
793		push_constant_def_equality_call_stack(WF,ID,Info,WF2),
794	?	b_compute_expression(SymArg2,LocalState,State,SV2,WF2),
795		(constant_variable_marked_as_expand(ID)
796		-> IDInfo = [marked_as_expand],
797		b_expand_compute_comprehension_set(SV2,Info,SV3,WF2)
798		; definitely_expand_this_explicit_set(SV2) % check for a few patterns which should definitely be expanded;
799		% in case user puts a set accidentally into the ABSTRACT_CONSTANTS section
800		-> IDInfo = [automatic_expand],
801		b_expand_compute_comprehension_set(SV2,Info,SV3,WF2)
802		; var(SV2) -> IDInfo = [], SV3=SV2
803		; IDInfo = [], % it is from ABSTRACT_CONSTANTS, but this info is already stored
804		mark_closure_as_symbolic(SV2,SV3)
805		),
806		get_waitflags_phase(WF,Phase), stop_constant_profile(SV3,Phase,ID,IDInfo,T1),
807		start_propagation_profile(ID,T2,CstL1),
808	?	kernel_call_predicate_equal_object_optimized(SV1,SV3,WF),
809		% profile propagation time and what constants are grounded
810		stop_propagation_profile(SV3,ID,T2,CstL1).
811
812		push_constant_def_equality_call_stack(WF,ID,Pos,WF2) :-
813		((constants_profiling_on ; get_preference(provide_trace_information,true))
814		-> push_wait_flag_call_stack_info(WF,
815		id_equality_evaluation(ID,constant,Pos),WF2)
816		; WF2=WF).
817
818		start_propagation_profile(ID,T1,CstL1) :-
819		(constants_profiling_on -> findall(Cst1,det_solution_for_constant_was_stored(Cst1),CstL1) ; CstL1=[]),
820		start_profile(ID,T1).
821		stop_propagation_profile(SV3,ID,T1,CstL1) :-
822		(constants_profiling_on
823		-> findall(Cst2,det_solution_for_constant_was_stored(Cst2),L2),
824		append(CstL1,New,L2), debug_format(9,'Propagation of value for ~w instantiated ~w~n',[ID,New]),
825		IDInfo2 = [instantiates(New)]
826		; IDInfo2 = []),
827		stop_constant_profile(SV3,propagate_value,ID,IDInfo2,T1).
828
829		% treat not(Arg1 = Arg2) predicates
830		b_test_atomic_not_equal_boolean_expression(Arg1,Arg2,_Info,LocalState,State,WF) :-
831		get_texpr_type(Arg1,boolean),!, % special treatment : not_equal_object has no type information
832		b_compute_expression(Arg1,LocalState,State,B1,WF),
833		b_compute_expression(Arg2,LocalState,State,B2,WF),
834		negate(B1,B2). % from bool_pred
835		b_test_atomic_not_equal_boolean_expression(Arg1,Arg2,_Info,LocalState,State,WF) :-
836		get_texpr_type(Arg1,integer),
837		preferences:preference(use_clpfd_solver,true),
838		!,
839		% Note: calling b_compute_arith_expression will also instantiate a variable to at least the int(_) skeleton; thereby enabling propagation
840		% this is potentially better than calling the default versions of the predicates, which may wait until the int(_) skeleton is set up before propagation
841	?	b_compute_arith_expression(Arg1,LocalState,State,CLPFD_Expr1,WF),
842	?	b_compute_arith_expression(Arg2,LocalState,State,CLPFD_Expr2,WF),
843		clpfd_interface:clpfd_neq_expr(CLPFD_Expr1,CLPFD_Expr2).
844		b_test_atomic_not_equal_boolean_expression(Arg1,Arg2,_Info,LocalState,State,WF) :-
845	?	b_compute_expression_symbolic(Arg1,LocalState,State,SV1,WF),
846	?	b_compute_expression_symbolic(Arg2,LocalState,State,SV2,WF),
847	?	kernel_call_predicate_not_equal_object(SV1,SV2,WF,not_equal(Arg1,Arg2)).
848		% Note: symbolic case occurs for symbolic abstract constants f when using DOUBLE_EVALUATION
849		% in the evaluation view which are defined by f = %x... when checking f /=
850
851		% a version of b_compute_expression which does not try to expand comprehension sets
852		% TODO: deal with other constructs which merit symbolic treatment; union of comprehension sets, ...
853		% (see line 147 in AMASS_mchs/oriented_abscissa.mch)
854		b_compute_expression_symbolic(Arg,LocalState,State,Val,WF) :-
855		(Arg = b(comprehension_set(PP,CC),_,InfoCS) % second arg is a comprehension set;
856		-> % write(symbolic(PP)),nl,
857	?	b_compute_comprehension_set_symbolic(PP,CC,InfoCS,LocalState,State,Val,WF)
858	?	; b_compute_expression(Arg,LocalState,State,Val,WF)
859		).
860		% ditto for already de-constructed b/3 expression:
861		b_compute_expression2_symbolic(comprehension_set(PP,CC),_,InfoCS,LocalState,State,Val,WF) :- !,
862		b_compute_comprehension_set_symbolic(PP,CC,InfoCS,LocalState,State,Val,WF).
863		b_compute_expression2_symbolic(Arg,Type,Info,LocalState,State,Val,WF) :-
864		b_compute_expression2(Arg,Type,Info,LocalState,State,Val,WF).
865
866		simple_expression(b(A,_,_)) :- simple_expression_aux(A).
867		simple_expression_aux(boolean_true).
868		simple_expression_aux(boolean_false).
869		simple_expression_aux(empty_set).
870		simple_expression_aux(empty_sequence).
871		simple_expression_aux(integer(_)).
872		simple_expression_aux(max_int).
873		simple_expression_aux(min_int).
874		simple_expression_aux(string(_)).
875		simple_expression_aux(value(_)).
876
877
878		is_lambda_result_id(b(identifier('_lambda_result_'),_,_)).
879		% at the moment we only detect those identifiers; the info field is currently not updated for _was_lambda_result_
880		% and not available in other treatmens of _lambda_result_ (in b_enumerate)
881		%is_lambda_result_id(b(identifier(X),_,Info)) :-
882		% memberchk(lambda_result,Info).
883		% (X=='_lambda_result_' -> (memberchk(lambda_result,Info) -> true ; format('~n*** _lambda_result_ without info: ~w~n~N',[Info])) ; memberchk(lambda_result,Info)).
884
885		%:- block b_lambda_result_equal_boolean_expression(-,?,?, -,?). % we now use when above
886		% only compute lambda result when finished finding domain element, i.e., _EWF is grounded
887		b_lambda_result_equal_boolean_expression(SV1,SV2,WF,EWF,WF2) :-
888	?	kernel_call_predicate_equal_object_optimized(SV1,SV2,WF),
889		% print(' LAMBDA : '), print((SV1,_EWF)),nl,
890		% the inner waitflags are for evaluating the lambda_result Expression; unless there is a WD issue this should
891		% never fail; we can delay the enumeration as much as possible
892		% NOTE: even if SV2 is ground, Arg2 may not be (e.g., if Arg2 = prj2(..,..)(NotGr,Ground))
893	?	blocking_ground_copied_wait_flags(WF2,EWF). % without when we will ground WF0 which is shared with outer WF-store
894		:- block blocking_ground_copied_wait_flags(?,-).
895		blocking_ground_copied_wait_flags(WF2,_) :-
896	?	ground_constraintprop_wait_flags(WF2). % do not ground EF flag, as shared with outer WF and WF2 is copied
897
898		% TO DO: add avl_set+closure expansion
899		%b_test_member_expression(Expr,El,_Set,_LocalState,_State,_WF) :-
900		% print('test member: '),print_bexpr(Expr),nl,fail.
901		b_test_member_expression(TElem,b(Set,Type,Info),LocalState,State,WF) :-
902	?	b_test_member_expression2(Set,Type,Info,TElem,LocalState,State,WF).
903
904		% new profiler
905		%:- use_module('../extensions/profiler/profiler.pl').
906		%:- use_module('../extensions/profiler/profiler_te.pl').
907		%:- enable_profiling(b_test_member_expression2/7).
908
909		% old profiler
910		%:- use_module(covsrc(hit_profiler)).
911
912		b_test_member_expression2(comprehension_set(Par,Cond),_Type,_Info,El,LocalState,State,WF) :-
913		% used to call in next clause below: b_generate_closure_if_necessary(Par,Cond,LocalState,State,SetValue,WF) /* will not expand closure */
914		/* 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 */
915		/* new version buys about 6 % for {x| x:1..400000 & x:{n|n >= 9000 & n<= 600000 & n mod 100 = 0}} (Sep 3 2014) */
916		set_up_typed_localstate(Par,ValueList,_TypedVals,LocalState,NewLocalState,positive),
917		!,
918		convert_list_into_pairs(ValueList,ElementVal),
919		b_compute_expression(El,LocalState,State,ElementVal,WF),
920		b_test_boolean_expression(Cond,NewLocalState,State,WF).
921		b_test_member_expression2(SymbolicSetConstant,_Type,_Info,El,LocalState,State,WF) :-
922		%hit_profiler:add_profile_hit(SymbolicSetConstant),
923		cst_in_boolean_type(SymbolicSetConstant,Module:Kernel_predicate),!, % two cases : string_set and integer_set
924		b_compute_expression(El,LocalState,State,ElValue,WF),
925		functor(KernelCall,Kernel_predicate,2),
926		arg(1,KernelCall,ElValue),
927		arg(2,KernelCall,WF),
928		% print_message(cst_in_boolean_type_call(KernelCall)),
929		kernel_call_predicate(KernelCall,Module,WF,SymbolicSetConstant). % should be member(... SymbolicSetConstant)
930		b_test_member_expression2(Expression,_Type,Info,El,LocalState,State,WF) :-
931		functor(Expression,BOP,2),
932		binary_in_boolean_type(BOP,Module:Kernel_predicate),!,
933		b_compute_expression(El,LocalState,State,ElValue,WF),
934		arg(1,Expression,Arg1),arg(2,Expression,Arg2),
935		(binary_in_definitely_true(BOP,ElValue)
936		-> % no need to compute arguments; unless required for WD:
937		check_well_defined(Arg1,LocalState,State,WF),
938		check_well_defined(Arg2,LocalState,State,WF)
939		; b_compute_expression(Arg1,LocalState,State,SV1,WF),
940	?	b_compute_expression(Arg2,LocalState,State,SV2,WF),
941		opt_push_wait_flag_call_stack_info(WF,b_operator_call(member,[ElValue,b_operator(BOP,[SV1,SV2])],Info),WF2),
942		% 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,
943	?	binary_in_kernel_call(Module,Kernel_predicate,ElValue,SV1,SV2,WF2,Expression)
944		).
945		b_test_member_expression2(Expression,_Type,Info,El,LocalState,State,WF) :-
946		functor(Expression,UnOP,1),
947		unary_in_boolean_type(UnOP,Module:Kernel_predicate),!,
948		b_compute_expression(El,LocalState,State,ElValue,WF),
949		arg(1,Expression,Arg1),
950		(unary_in_definitely_true(UnOP,ElValue)
951		-> % no need to compute arguments; unless required for WD:
952		check_well_defined(Arg1,LocalState,State,WF)
953	?	; b_compute_expression(Arg1,LocalState,State,SV1,WF),
954		opt_push_wait_flag_call_stack_info(WF,b_operator_call(member,[ElValue,b_operator(UnOP,[SV1])],Info),WF2),
955	?	unary_in_kernel_call(Module,Kernel_predicate,ElValue,SV1,WF2,Expression)
956		).
957		b_test_member_expression2(SetExpression,Type,Info,El,LocalState,State,WF) :-
958	?	b_compute_expression2(SetExpression,Type,Info,LocalState,State,SetValue,WF),
959		(always_well_defined_or_disprover_mode(El)
960		-> SetValue \== [] % if we have the empty set: check_element will always fail
961		; true % we could check SetValue \== [] if find_abort_values=false ??
962		),
963	?	b_compute_expression(El,LocalState,State,Element,WF),
964		Span = El, % Info is quite often the empty list
965		(not_invertible(El) % then no sense in setting up member constraint f(...) : SetValue ;
966		% we cannot used the info anyway; but we could enumerate
967		-> % we wait until Element is fully known before doing the check
968		ground_value_check(Element,GrEl),
969	?	when(nonvar(GrEl),kernel_call_predicate_check_element_of_wf(Element,SetValue,WF,Span))
970	?	; kernel_call_predicate_check_element_of_wf(Element,SetValue,WF,Span)).
971
972		:- use_module(external_functions,[external_fun_can_be_inverted/1]).
973		not_invertible(b(E,_,_)) :- not_inv_aux(E).
974		not_inv_aux(external_function_call(FunName,_Args)) :- \+ external_fun_can_be_inverted(FunName).
975		% TO DO: capture other cases like function applications
976		% TO DO: also do this in b_interpreter_check ?
977		% TO DO: We should compute this information in ast_cleanup; e.g., what if we do STRING_TO_INT(s)+1 : SET
978
979		% 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) ?
980
981		:- use_module(kernel_lists,[not_element_of_list_wf/3]).
982		b_test_notmember_expression(set_extension(Ex),El,_Set,_,LocalState,State,WF) :- !,
983		b_compute_expressions(Ex,LocalState,State,ExValueList,WF),
984		b_compute_expression(El,LocalState,State,ElementVal,WF),
985		not_element_of_list_wf(ElementVal,ExValueList,WF).
986		b_test_notmember_expression(SymbolicSetCst,El,_Set,_,LocalState,State,WF) :-
987		kernel_mappings:cst_not_in_boolean_type(SymbolicSetCst,Module:Kernel_predicate),!,
988		b_compute_expression(El,LocalState,State,ElValue,WF),
989		functor(KernelCall,Kernel_predicate,1),
990		arg(1,KernelCall,ElValue),
991		% debug_print(cst_not_in_boolean_type(9,KernelCall)),
992		kernel_call_predicate(KernelCall,Module,WF,SymbolicSetCst).
993		b_test_notmember_expression(Expression,El,_Set,Info,LocalState,State,WF) :-
994		functor(Expression,BOP,2),
995		kernel_mappings:binary_not_in_boolean_type(BOP,Module:Kernel_predicate),!,
996		b_compute_expression(El,LocalState,State,ElValue,WF),
997		\+ binary_in_definitely_true(BOP,ElValue),
998		arg(1,Expression,Arg1),arg(2,Expression,Arg2),
999		b_compute_expression(Arg1,LocalState,State,SV1,WF),
1000		b_compute_expression(Arg2,LocalState,State,SV2,WF),
1001		% KernelCall =.. [Kernel_predicate,ElValue,SV1,SV2,WF],
1002		opt_push_wait_flag_call_stack_info(WF,b_operator_call(not_member,[ElValue,b_operator(BOP,[SV1,SV2])],Info),WF2),
1003	?	kernel_call_predicate3(Kernel_predicate,ElValue,SV1,SV2,Module,WF2,Expression).
1004		b_test_notmember_expression(Expression,El,_Set,Info,LocalState,State,WF) :-
1005		functor(Expression,UnOP,1),
1006		unary_not_in_boolean_type(UnOP,Module:Kernel_predicate),!,
1007		b_compute_expression(El,LocalState,State,ElValue,WF),
1008		\+ unary_in_definitely_true(UnOP,ElValue),
1009		arg(1,Expression,Arg1),
1010		b_compute_expression(Arg1,LocalState,State,SV1,WF),
1011		%KernelCall =.. [Kernel_predicate,ElValue,SV1,WF],
1012		%kernel_call_predicate(KernelCall,Module,WF,Expression).
1013		opt_push_wait_flag_call_stack_info(WF,b_operator_call(not_member,[ElValue,b_operator(UnOP,[SV1])],Info),WF2),
1014		kernel_call_predicate2(Kernel_predicate,ElValue,SV1,Module,WF2,Expression).
1015		b_test_notmember_expression(Expr,Elem,Set,_Info,LocalState,State,WF) :-
1016		(Expr=comprehension_set(Par,Cond)
1017		-> b_generate_closure_if_necessary(Par,Cond,LocalState,State,SetValue,WF) /* will not expand closure */
1018		; b_compute_expression(Set,LocalState,State,SetValue,WF)
1019		),
1020		(SetValue == []
1021		-> /* nothing can be member of empty set */
1022		check_well_defined(Elem,LocalState,State,WF)
1023		% we could disable this check if find_abort_values=true
1024		; b_compute_expression(Elem,LocalState,State,ElemValue,WF),
1025		%kernel_call_predicate2(not_element_of_wf,ElemValue,SetValue,kernel_objects,WF,Expr)
1026		%kernel_call_predicate(not_element_of_wf(ElemValue,SetValue,WF),kernel_objects,WF,Expr)
1027		kernel_call_predicate_not_element_of_wf(ElemValue,SetValue,WF)
1028		).
1029
1030		:- block block_test_implication(?,?,?,?,?,-).
1031		block_test_implication(LHS,RHS,LocalState,State,WF,_WF2) :-
1032	?	b_test_inner_boolean_expression(LHS,LocalState,State,WF),
1033		b_test_inner_boolean_expression(RHS,LocalState,State,WF).
1034		block_test_implication(LHS,_RHS,LocalState,State,WF,_WF2) :-
1035		b_not_test_inner_boolean_expression(LHS,LocalState,State,WF).
1036
1037
1038		b_test_equivalence(LHS,RHS,LocalState,State,WF,Ai,Ao) :-
1039		copy_wf_start(WF,equivalence,CWF),
1040		if(b_check_boolean_expression(LHS,LocalState,State,CWF,PredRes,Ai,Aii),
1041	?	(b_check_test_equivalence(PredRes,LHS,RHS,LocalState,State,CWF,Aii,Ao),
1042		copy_wf_finish(WF,CWF)),
1043		(% check LHS fails, We could check if RHS can be checked with b_check_boolean_expression
1044		Ai=Ao, get_binary_choice_wait_flag(equivalence,WF,WF2),
1045		b_enum_test_equivalence(LHS,RHS,LocalState,State,WF,WF2,Ai))).
1046		b_not_test_equivalence(LHS,RHS,LocalState,State,WF,Ai,Ao) :-
1047		copy_wf_start(WF,not_equivalence,CWF),
1048		if(b_check_boolean_expression(LHS,LocalState,State,CWF,PredRes,Ai,Aii),
1049		(negate(PredRes,NegPredRes), % from bool_pred
1050	?	b_check_test_equivalence(NegPredRes,LHS,RHS,LocalState,State,CWF,Aii,Ao),
1051		copy_wf_finish(WF,CWF)),
1052		(% check LHS fails, We could check if RHS can be checked with b_check_boolean_expression
1053		Ai=Ao, get_binary_choice_wait_flag(not_equivalence,WF,WF2),
1054		b_enum_not_test_equivalence(LHS,RHS,LocalState,State,WF,WF2,Ai))).
1055		b_check_test_equivalence(PredRes,LHS,RHS,LocalState,State,WF,Aii,Ao) :-
1056		% print('checking <=> '), print_bexpr(LHS), print(' '), print(PredRes),nl,
1057	?	(var(PredRes),b_check_boolean_expression(RHS,LocalState,State,WF,PredRes2,Aii,Ao) % TO DO <---- REPLACE CUT
1058		-> /* also propagate from right to left */
1059	?	equiv_bidrectional_test_boolean_expression(PredRes,PredRes2,LHS,RHS,LocalState,State,WF)
1060		; Aii=Ao,
1061	?	equiv_test_boolean_expression(PredRes,pred_true,RHS,LocalState,State,WF,Aii)
1062		). % should we also add a binary choice flag ?? what about a=2 <=> b/=3 ??
1063
1064		:- block b_enum_test_equivalence(?,?,?,?,?,-,?).
1065		b_enum_test_equivalence(LHS,RHS,LocalState,State,WF,_WF2,Ai) :-
1066		b_test_boolean_expression(LHS,LocalState,State,WF,Ai,Aii), % TO DO: we could call b_test_inner_boolean_expression with Ai
1067		b_test_boolean_expression(RHS,LocalState,State,WF,Aii,_).
1068		b_enum_test_equivalence(LHS,RHS,LocalState,State,WF,_WF2,Ai) :-
1069		b_not_test_boolean_expression(LHS,LocalState,State,WF,Ai,Aii),
1070		b_not_test_boolean_expression(RHS,LocalState,State,WF,Aii,_).
1071
1072		%enumerate_bool(X,WF) :- !.
1073		enumerate_bool(X,Prio,WF) :- (nonvar(X) -> true /* already set */
1074		; get_wait_flag0(WF,WF0),
1075		enumerate_bool0(X,Prio,WF,WF0)).
1076
1077		:- block enumerate_bool0(?,?,?,-).
1078		enumerate_bool0(X,Prio,WF,_) :- (nonvar(X) -> true /* already set */
1079		; %print(enum_bool(X)), translate:print_bexpr(LHS),nl,
1080		% get_binary_choice_wait_flag(enumerate_bool,WF,WF2),
1081		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
1082		enumerate_bool_aux(X,WF2)).
1083		:- block enumerate_bool_aux(-,-).
1084		%enumerate_bool_aux(P,WF) :- var(P),print(forcing_bool(P,WF)),nl,fail. %
1085		enumerate_bool_aux(pred_true,_).
1086		enumerate_bool_aux(pred_false,_).
1087
1088		:- block b_test_disjunction(?,?,?,?,?,-,?).
1089		b_test_disjunction(LHS,_RHS,LocalState,State,WF,_WF2,Ai) :-
1090	?	b_test_boolean_expression(LHS,LocalState,State,WF,Ai,_).
1091		b_test_disjunction(LHS,RHS,LocalState,State,WF,_WF2,Ai) :-
1092	?	b_not_test_boolean_expression(LHS,LocalState,State,WF,Ai,Aii),
1093	?	b_test_boolean_expression(RHS,LocalState,State,WF,Aii,_).
1094
1095		:- block b_not_test_conjunction(?,?,?,?,?,-,?).
1096		b_not_test_conjunction(LHS,_RHS,LocalState,State,WF,_WF2,Ai) :-
1097	?	b_not_test_boolean_expression(LHS,LocalState,State,WF,Ai,_).
1098		b_not_test_conjunction(LHS,RHS,LocalState,State,WF,_WF2,Ai) :-
1099	?	b_test_boolean_expression(LHS,LocalState,State,WF,Ai,Aii),
1100	?	b_not_test_boolean_expression(RHS,LocalState,State,WF,Aii,_).
1101
1102		:- block b_enum_not_test_equivalence(?,?,?,?,?,-,?).
1103		b_enum_not_test_equivalence(LHS,RHS,LocalState,State,WF,_WF2,Ai) :-
1104		b_test_boolean_expression(LHS,LocalState,State,WF,Ai,Aii), % we could call b_test_inner_boolean_expression with Ai
1105		b_not_test_boolean_expression(RHS,LocalState,State,WF,Aii,_).
1106		b_enum_not_test_equivalence(LHS,RHS,LocalState,State,WF,_WF2,Ai) :-
1107		b_not_test_boolean_expression(LHS,LocalState,State,WF,Ai,Aii),
1108		b_test_boolean_expression(RHS,LocalState,State,WF,Aii,_).
1109
1110
1111
1112		/* --------------------------------------*/
1113		/* b_not_test_boolean_expression */
1114		/* --------------------------------------*/
1115
1116		b_not_test_list_of_boolean_expression([],_,_,_WF).
1117		b_not_test_list_of_boolean_expression([B1|T],LS,S,WF) :-
1118		b_not_test_boolean_expression(B1,LS,S,WF),
1119		b_not_test_list_of_boolean_expression(T,LS,S,WF).
1120
1121		:- assert_pre(b_interpreter:b_not_test_boolean_expression_cs(E,LS,S,_,_),
1122		(bsyntaxtree:check_if_typed_predicate(E),type_check(LS,store),type_check(S,store))).
1123		:- assert_post(b_interpreter:b_not_test_boolean_expression_cs(_,_,_,_,_), true).
1124
1125
1126		% a version where we can provide an initial call stack entry for context
1127		b_not_test_boolean_expression_cs(E,LS,S,PredKind,Nr) :-
1128		init_wait_flags_cs(E,PredKind,Nr,b_not_test_boolean_expression_cs,WF), % TODO: we could register negation info
1129		% TO DO: call b_trace_test_components ?
1130	?	b_not_test_boolean_expression(E,LS,S,WF),
1131	?	ground_wait_flags(WF).
1132
1133		b_not_test_boolean_expression(E,LS,S,WF) :-
1134	?	empty_avl(Ai), b_not_test_boolean_expression(E,LS,S,WF,Ai,_).
1135
1136		:- assert_pre(b_interpreter:b_not_test_boolean_expression(E,LS,S,WF),
1137		(type_check(E,boolean_expression),type_check(LS,store),type_check(S,store), type_check(WF,wait_flag))).
1138		:- assert_post(b_interpreter:b_not_test_boolean_expression(_,_,_,_), true).
1139
1140		:- if(environ(prob_debug_watch_flag,true)).
1141		b_not_test_boolean_expression(b(Expr,_,Infos),LS,S,WF,Ai,Ao) :- !,
1142		(waitflag0_is_set(WF)
1143		-> debug:watch(400,b_interpreter:b_not_test_boolean_expression2(Expr,Infos,LS,S,WF,Ai,Ao))
1144		; debug:watch_det(400,b_interpreter:b_not_test_boolean_expression2(Expr,Infos,LS,S,WF,Ai,Ao)) ).
1145		:- else.
1146		b_not_test_boolean_expression(b(Expr,Type,Infos),LS,S,WF,Ai,Ao) :- !,
1147		(preference(smt_supported_interpreter,true)
1148		-> b_not_test_boolean_expression2(Expr,Infos,LS,S,WF,Ai,Ao),create_negation(b(Expr,Type,Infos),Neg),
1149		get_wait_flag1(smt_call,WF,BeforeEnumWF),
1150		gensym:gensym(smt_assertion_name,Symbol),
1151		smt_add_predicate(BeforeEnumWF,Neg,LS,S,Symbol)
1152	?	; b_not_test_boolean_expression2(Expr,Infos,LS,S,WF,Ai,Ao)).
1153		:- endif.
1154		b_not_test_boolean_expression(E,LS,S,WF,Ai,Ao) :-
1155		add_internal_error('Boolean (not) expression not properly wrapped: ',
1156		b_not_test_boolean_expression(E,LS,S,WF,Ai,Ao)),
1157		b_not_test_boolean_expression2(E,[],LS,S,WF,Ai,Ao).
1158
1159		b_not_test_boolean_expression2(truth,_,_,_,_WF,_Ai,_Ao) :- !,fail.
1160		b_not_test_boolean_expression2(falsity,_,_,_,_WF,Ai,Ao) :- !,Ai=Ao. % NOT COVERED (2)
1161		b_not_test_boolean_expression2(negation(BExpr),_,LocalState,State,WF,Ai,Ao) :- !,
1162	?	b_test_boolean_expression(BExpr,LocalState,State,WF,Ai,Ao).
1163		% following makes test 349 fail:
1164		%b_not_test_boolean_expression2(conjunct(LHS,RHS),Infos,LocalState,State,WF,Ai,Ao) :- !,
1165		% nl, print(' NOT: '),translate:print_bexpr(b(conjunct(LHS,RHS),pred,Infos)),nl,
1166		% create_negation(LHS,NegLHS), % TO DO: avoid this construction by generalising code for disjunct
1167		% create_negation(RHS,NegRHS),
1168		% b_test_boolean_expression2(disjunct(NegLHS,NegRHS),Infos,LocalState,State,WF,Ai,Ao).
1169		b_not_test_boolean_expression2(conjunct(LHS,RHS),Infos,LocalState,State,WF,Ai,Ao) :- !,
1170		b(conjunct(LHS,RHS),pred,Infos) = Conj,
1171		copy_wf_start(WF,not_conjunct,CWF),
1172	?	if(b_check_boolean_expression(Conj,LocalState,State,CWF,PredRes,Ai,Ao),
1173		(PredRes=pred_false,
1174	?	copy_wf_finish(WF,CWF)
1175		),
1176	?	if(b_check_boolean_expression(LHS,LocalState,State,CWF,LHSPredRes,Ai,Ao), % some redundant work with call above: TODO: avoid !
1177		(copy_wf_finish(WF,CWF),
1178		get_last_wait_flag(not_conjunct_rhs,WF,WF2), % before starting to enumerate infinite types: better try both possibilities:
1179	?	b_not_test_conjunction_rhs(LHSPredRes,RHS,LocalState,State,WF,Ai,WF2)
1180		),
1181		(Ai=Ao,
1182		get_priority_of_boolean_expression2(disjunct(LHS,RHS),StartPrio),
1183		%get_wait_flag(Prio,not_conjunct,WF,WF2),
1184		get_binary_choice_wait_flag_exp_backoff(StartPrio,not_conjunct,WF,WF2),
1185		% TO DO: we could check if LHS or RHS are registered in Ai as pred_true/pred_false ??
1186		b_not_test_conjunction(LHS,RHS,LocalState,State,WF,WF2,Ai))
1187		)
1188		).
1189
1190		b_not_test_boolean_expression2(implication(LHS,RHS),_,LocalState,State,WF,Ai,Ao) :- !,
1191		b_test_boolean_expression(LHS,LocalState,State,WF,Ai,Aii),
1192	?	b_not_test_boolean_expression(RHS,LocalState,State,WF,Aii,Ao).
1193		b_not_test_boolean_expression2(equivalence(LHS,RHS),_,LocalState,State,WF,Ai,Ao) :- !,
1194	?	b_not_test_equivalence(LHS,RHS,LocalState,State,WF,Ai,Ao).
1195		b_not_test_boolean_expression2(disjunct(LHS,RHS),_,LocalState,State,WF,Ai,Ao) :- !,
1196	?	b_not_test_boolean_expression(LHS,LocalState,State,WF,Ai,Aii),
1197	?	b_not_test_boolean_expression(RHS,LocalState,State,WF,Aii,Ao).
1198		b_not_test_boolean_expression2(lazy_let_pred(Id,AssignmentExpr,Expr),_I,LocalState,State,WF,Ai,Ao) :- !,
1199		add_lazy_let_id_and_expression(Id,AssignmentExpr,LocalState,State,NewLocalState,WF,Ai),
1200		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
1201		b_not_test_boolean_expression2(lazy_lookup_pred(Id),_Info,LocalState,_State,WF,Ai,Ao) :- !, Ai=Ao,
1202		lookup_value_for_existing_id_wf(Id,LocalState,(Trigger,Value),WF), % should normally only occur in LocalState; value introduced by lazy_let
1203		(Trigger,Value) = (pred_true,pred_false). % force evaluation
1204		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
1205		is_pred_false(PredVal),Ai=Ao.
1206		b_not_test_boolean_expression2(Expr,Info,LocalState,State,WF,Ai,Ao) :-
1207		% TO DO: we could put some of the operators into the Ai store (comparison operators)
1208	?	b_not_test_atomic_boolean_expression2(Expr,Info,LocalState,State,WF,Ai,Ao).
1209
1210		% Other boolean expressions, not involving boolean connectives
1211		b_not_test_atomic_boolean_expression2(exists(Parameters,RHS),Infos,LocalState,State,WF,Ai,Ao) :- !,
1212		/* #ID.(RHS) */
1213		Ai=Ao,
1214	?	b_not_test_exists(Parameters,RHS,Infos,LocalState,State,compile,WF).
1215		b_not_test_atomic_boolean_expression2(forall(Parameters,LHS,RHS),Infos,LocalState,State,WF,Ai,Ao) :- !,
1216		/* !ID.(LHS => RHS) */
1217		Ai=Ao,
1218		safe_create_texpr(negation(RHS),pred,Negation),
1219		conjunct_predicates_with_pos_info(LHS,Negation,Condition),
1220		% conjunct_predicates merges the used_ids Info in Condition
1221	?	b_test_exists(Parameters,Condition,Infos,LocalState,State,WF).
1222		/* TODO(DP, 2.8.2008): Extension for Z: a let-statement as predicate */
1223		b_not_test_atomic_boolean_expression2(let_predicate(Ids,AssignmentExprs,Pred),Infos,LocalState,State,WF,Ai,Ao) :-
1224		!,Ai=Ao, % any expression inside the LET cannot be safely reused
1225	?	set_up_localstate_for_let(Ids,ParaValues,AssignmentExprs,LocalState,State,LetState,WF),
1226		opt_push_wait_flag_call_stack_quantifier_info(WF,let_quantifier,Ids,ParaValues,Infos,WF2),
1227	?	b_not_test_boolean_expression(Pred,LetState,State,WF2). % NOT COVERED (10)
1228		/* TODO(DP, 2.8.2008): */
1229		b_not_test_atomic_boolean_expression2(freetype_case(Freetype,Case,Expr),_,LocalState,State,WF,Ai,Ao) :-
1230		!,Ai=Ao,b_compute_expression(Expr,LocalState,State,freeval(Freetype,RealCase,_),WF),
1231		dif(RealCase,Case). % NOT COVERED (11)
1232		b_not_test_atomic_boolean_expression2(finite(SetExpr),_,LocalState,State,WF,Ai,Ao) :-
1233		!, Ai=Ao,b_compute_expression(SetExpr,LocalState,State,Value,WF),
1234		kernel_call_predicate(is_infinite_set_wf(Value,WF),kernel_objects,WF,finite(SetExpr)).
1235		/* Extension for Kodkod */
1236		b_not_test_atomic_boolean_expression2(kodkod(ProblemId,_),_,LocalState,State,WF,Ai,Ao) :-
1237		!,Ai=Ao,get_wait_flag1(kodkod_negative_call,WF,WF0),
1238		kodkod_request(ProblemId,neg,LocalState,State,WF0). % NOT COVERED (12)
1239		b_not_test_atomic_boolean_expression2(partition(LHS,RHS),Info,LocalState,State,WF,Ai,Ao) :- !,
1240		b_interpreter_check:register_predicate(partition(LHS,RHS),Info,pred_false,Reused,Ai,Ao),
1241		(Reused==true -> true
1242		; b_compute_expression(LHS,LocalState,State,SV1,WF),
1243		l_compute_expression(RHS,LocalState,State,SV2,WF), % RHS is Prolog list of expressions
1244		kernel_call_predicate(not_partition_wf(SV1,SV2,WF),kernel_objects,WF,partition(LHS,RHS))
1245		).
1246		b_not_test_atomic_boolean_expression2(external_pred_call(FunName,Args),Info,LocalState,State,WF,Ai,Ao) :-
1247		!, Ai=Ao,
1248		(do_not_evaluate_args(FunName) -> EvaluatedArgs=[]
1249		; b_compute_expressions(Args, LocalState,State, EvaluatedArgs, WF)),
1250		push_wait_flag_call_stack_info(WF,external_call(FunName,EvaluatedArgs,Info),WF2),
1251		call_external_predicate(FunName,Args,EvaluatedArgs,LocalState,State,pred_false,Info,WF2).
1252		b_not_test_atomic_boolean_expression2(Pred,Info,LocalState,State,WF,Ai,Ao) :-
1253		b_interpreter_check:register_predicate(Pred,Info,pred_false,Reused,Ai,Ao),
1254		(Reused==true
1255		-> %% print('REUSED (not): '), translate:print_bexpr(Pred),nl,
1256		true
1257	?	; b_not_test_atomic_boolean_expression3(Pred,Info,LocalState,State,WF)).
1258		b_not_test_atomic_boolean_expression3(Expression,Info,LocalState,State,WF) :-
1259		functor(Expression,BOP,2),
1260	?	kernel_mappings:negate_binary_boolean_operator(BOP,NBOP),
1261		arg(1,Expression,Arg1),arg(2,Expression,Arg2),!,
1262		NExpression =.. [NBOP,Arg1,Arg2],
1263	?	b_test_atomic_boolean_expression2(NExpression,Info,LocalState,State,WF).
1264		b_not_test_atomic_boolean_expression3(Expression,Info,LocalState,State,WF) :-
1265		functor(Expression,BOP,2),
1266		kernel_mappings:negate_binary_boolean_operator_swap(BOP,NBOP),
1267		arg(1,Expression,Arg1),arg(2,Expression,Arg2),!,
1268		NExpression =.. [NBOP,Arg2,Arg1],
1269		b_test_atomic_boolean_expression2(NExpression,Info,LocalState,State,WF).
1270		b_not_test_atomic_boolean_expression3(E,_,_,_,_WF) :-
1271		add_internal_error('Uncovered boolean expression (not): ',E),
1272		print_functor(E),nl,fail.
1273
1274
1275		% test RHS of not-conjunction depending on outcome of LHS
1276		:- block b_not_test_conjunction_rhs(-,?,?,?,?,?,-).
1277		b_not_test_conjunction_rhs(pred_false,_RHS,_LocalState,_State,_WF,_Ai,_LWF).
1278		b_not_test_conjunction_rhs(pred_true,RHS,LocalState,State,WF,Ai,_LWF) :-
1279	?	b_not_test_boolean_expression(RHS,LocalState,State,WF,Ai,_).
1280
1281		/* -----------------------------*/
1282		/* b_compute_expression */
1283		/* -----------------------------*/
1284
1285
1286
1287		:- assert_must_succeed((b_interpreter:b_compute_expression(b(pow_subset(
1288		b(identifier(nm),set(integer),[])),set(set(integer)),[]),
1289		[], [bind(nm,[])],R,_WF),
1290		nonvar(R), custom_explicit_sets:expand_custom_set_to_list(R,[[]]))).
1291		:- assert_must_succeed((b_interpreter:b_compute_expression(b(pow_subset(
1292		b(identifier(nm),set(boolean),[])),set(set(boolean)),[]),[],
1293		[bind(nm,[pred_false /* bool_false */])],R,_WF),
1294		nonvar(R), custom_explicit_sets:expand_custom_set_to_list(R,ER),
1295		kernel_objects:equal_object(ER,[[pred_false /* bool_false */],[]]))).
1296
1297		:- assert_pre(b_interpreter:b_compute_expression(Exp,LS,State,_Val,WF),
1298		(nonvar(Exp),
1299		bsyntaxtree:check_if_typed_expression(Exp),
1300		type_check(LS,store),type_check(State,store), type_check(WF,wait_flag))).
1301		:- assert_post(b_interpreter:b_compute_expression(_E,_LS,_State,Val,WF),
1302		(b_interpreter:value_type(Val), type_check(WF,wait_flag))). %, nonvar(Val)
1303
1304		b_compute_expression_nowf(E,LS,S,R) :-
1305		b_compute_expression_nowf(E,LS,S,R,none,0).
1306
1307		b_compute_expression_nowf(E,LS,S,R,FormulaKind,Nr) :-
1308		get_texpr_info(E,Info),
1309	?	b_compute_expression_nowf(E,LS,S,R,FormulaKind,Nr,Info).
1310		b_compute_expression_nowf(E,LS,S,R,FormulaKind,Nr,Span) :-
1311	?	b_compute_expression_no_wf8(E,LS,S,R,FormulaKind,Nr,default,Span).
1312		% a variation where we tell ProB to expect non-symbolic / explicit values
1313		b_compute_explicit_epression_no_wf(E,LS,S,R,FormulaKind,Nr) :-
1314		get_texpr_info(E,Info),
1315	?	b_compute_explicit_epression_no_wf(E,LS,S,R,FormulaKind,Nr,Info).
1316		b_compute_explicit_epression_no_wf(E,LS,S,R,FormulaKind,Nr,Span) :-
1317	?	b_compute_expression_no_wf8(E,LS,S,R,FormulaKind,Nr,expect_explicit_value,Span).
1318		b_compute_expression_no_wf8(E,LS,S,R,FormulaKind,Nr,Expect,Span) :-
1319		%add_message(b_compute_expression,'Called Version wo WFLAGS: ', b_compute_expression(E,LS,S,R)),
1320		(Expect=expect_explicit_value -> WFInfos = [expect_explicit_value] ; WFInfos = []),
1321		(FormulaKind = none -> init_wait_flags(WF,WFInfos)
1322		; CallStackEntry = prob_command_context(eval_expr_command(FormulaKind,Nr),Span),
1323		init_wait_flags_and_push_call_stack(no_wf_available,CallStackEntry,WFInfos,WF)
1324		),
1325	?	b_compute_expression(E,LS,S,R,WF),
1326	?	ground_wait_flags(WF), % this will add abort errors and fail before enumerating the result:
1327		init_wait_flags(WF2,[b_compute_expression_nowf2]),
1328		get_texpr_type(E,Type),
1329		b_enumerate:b_tighter_enumerate_single_value(R,Type,Span,b_compute_expression_nowf,WF2), %should rarely be necessary
1330		% a non-ground result only occurs when WD error appears and in this case ground_wait_flags will fail after
1331		% adding the abort error (and thus no value is returned)
1332		% exceptions are test 1066 with a complicated set comprehension used in a function application
1333		% test 1861 relies on two phase enumeration
1334		ground_wait_flags(WF2).
1335
1336		l_compute_expression([],_LS,_S,[],_WF).
1337		l_compute_expression([H|T],LS,S,[CH|CT],WF) :-
1338		b_compute_expression(H,LS,S,CH,WF),
1339		l_compute_expression(T,LS,S,CT,WF).
1340
1341		:- if(environ(prob_debug_watch_flag,true)).
1342		b_compute_expressiond(b(Expr,Type,Info),LS,S,R,WF) :- !,
1343		((ground(Type), Type \== pred, Type \== subst) -> true
1344		; add_error_wf(b_compute_expression,'Expression has illegal type: ',b(Expr,Type,Info),Info,WF)),
1345		check_value(R,b(Expr,Type,Info)),
1346		b_compute_expression2(Expr,Type,Info,LS,S,R,WF).
1347		:- block check_value(-,?).
1348		check_value(pred_true,_) :- !. check_value(pred_false,_) :- !.
1349		check_value(string(_),_) :- !.
1350		check_value([],_) :- !.
1351		check_value([H|T],E) :- !, check_value(H,E), check_value(T,E).
1352		check_value((A,B),E) :- !, check_value(A,E), check_value(B,E).
1353		check_value(fd(N,T),E) :- !, (nonvar(T) -> check_fd(N,T,E) ; check_err(fd(N,T),E)).
1354		check_value(global_set(GS),E) :- !,(nonvar(GS) -> true ; check_err(global_set(GS),E)).
1355		check_value(avl_set(AS),E) :- !,((nonvar(AS),AS=node(_,_,_,_,_)) -> true ; check_err(global_set(AS),E)).
1356		check_value(int(X),E) :- !,check_int(X,E).
1357		check_value(closure(P,T,B),E) :- !,
1358		(ground(P),ground(T),nonvar(B)
1359		-> (same_length(P,T) -> bsyntaxtree:check_ast(B) ; check_err(closure_not_same_length(P,T)))
1360		; check_err(closure(P,T,B),E)).
1361		check_value(rec(_),_) :- !. %TODO: check
1362		check_value(X,E) :- check_err(uncovered(X),E).
1363		% TO DO: add records + more thorough checking of global_set and closures and avl_sets
1364		:- block check_int(-,?).
1365		check_int(X,E) :- (number(X) -> true ; check_err(int(X),E)).
1366		:- block check_fd(-,?,?).
1367		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)).
1368
1369		check_err(V,E) :- add_internal_error('Illegal value when computing expression: ',V:E).
1370		b_compute_expression(E,LS,S,R,WF) :- !,
1371		(waitflag0_is_set(WF)
1372		-> debug:watch(100,b_interpreter:b_compute_expressiond(E,LS,S,R,WF))
1373		; debug:watch_det(100,b_interpreter:b_compute_expressiond(E,LS,S,R,WF))).
1374		:- else.
1375		b_compute_expression(b(Expr,Type,Info),LS,S,R,WF) :- !,
1376		((ground(Type), Type \== pred, Type \== subst) -> true
1377		; Type==pred -> add_internal_error_wf(b_interpreter,'Expected expression, not predicate: ',b(Expr,Type,Info),Info,WF)
1378		; Type==subst -> add_internal_error_wf(b_interpreter,'Expected expression, not substitution: ',b(Expr,Type,Info),Info,WF)
1379		; add_internal_error_wf(b_interpreter,'Expression has non-ground type: ',b(Expr,Type,Info),Info,WF)
1380		),
1381	?	b_compute_expression2(Expr,Type,Info,LS,S,R,WF).
1382		:- endif.
1383		b_compute_expression(Expr,LS,S,R,WF) :-
1384		add_internal_error('Expression not properly wrapped: ',b_compute_expression(Expr,LS,S,R,WF)),
1385		b_compute_expression2(Expr,unknown,[],LS,S,R,WF).
1386
1387
1388		:- use_module(bsyntaxtree,[get_texpr_set_type/2]).
1389
1390		%:- use_module(b_global_sets,[b_type2_set/2]).
1391		%b_compute_expression2(V,T,I,LS,S,R,_WF) :- nonvar(R), print('result_instantiated: '(R:V)),nl,fail.
1392	?	b_compute_expression2(value(Val),_T,_I,_LS,_S,V,WF) :- !, equal_object_wf(Val,V,WF). %Val=V.
1393		b_compute_expression2(boolean_true,_T,_I,_LState,_State,Res,_WF) :- !, Res = pred_true /* bool_true */. % for simple types we can use ordinary unification
1394		b_compute_expression2(boolean_false,_T,_I,_LState,_State,Res,_WF) :- !, Res = pred_false /* bool_false */.
1395		b_compute_expression2(integer_set(NSET),_T,_I,_LState,_State,Res,WF) :- !, equal_object_wf(Res,global_set(NSET),WF). %Res = global_set(NSET).
1396		b_compute_expression2(bool_set,_T,_I,_LState,_State,Res,WF) :- !, % b_type2_set(bool,Res).
1397		equal_object_wf(Res,avl_set(node(pred_false,true,1,empty,node(pred_true,true,0,empty,empty))),WF).
1398		% 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
1399		b_compute_expression2(float_set,_T,_I,_LState,_State,Res,WF) :- !, equal_object_wf(Res,global_set('FLOAT'),WF).
1400		b_compute_expression2(real_set,_T,_I,_LState,_State,Res,WF) :- !, equal_object_wf(Res,global_set('REAL'),WF).
1401		b_compute_expression2(string_set,_T,_I,_LState,_State,Res,WF) :- !, equal_object_wf(Res,global_set('STRING'),WF).
1402		% was all_strings(Res). %% NOT COVERED (6)
1403		b_compute_expression2(string(S),_T,_I,_LState,_State,Res,_WF) :- !,
1404		% TODO(ML,26.8.2008): Check if we should use a different functor for syntax tree vs data
1405		Res = string(S).
1406		b_compute_expression2(typeset,Type,_I,_LState,_State,Res,WF) :- !,
1407		is_set_type(Type,ElType), % we could generate global_set('STRING'),... for certain types
1408		equal_object_wf(Res,closure('_zzzz_unary',[ElType],b(truth,pred,[])),WF).
1409		b_compute_expression2(empty_set,_T,_I,_LState,_State,Res,_WF) :- !, empty_set(Res).
1410		b_compute_expression2(empty_sequence,_T,_I,_LState,_State,Res,_WF) :- !, empty_sequence(Res).
1411		b_compute_expression2(event_b_identity,EType,_I,_LState,_State,Res,WF) :-
1412		get_set_type(EType,couple(Type,Type)),!,
1413		event_b_identity_for_type(Type,Res,WF).
1414		b_compute_expression2(integer(Val),_T,_I,_LocalState,_State,Res,_WF) :- !, Res = int(Val).
1415		b_compute_expression2(max_int,_T,_I,_LS,_S,Res,_WF) :-
1416		preferences:get_preference(maxint,CVal),!, Res = int(CVal).
1417		b_compute_expression2(min_int,_T,_I,_LS,_S,Res,_WF) :-
1418		preferences:get_preference(minint,CVal),!, Res = int(CVal).
1419		b_compute_expression2(identifier(Id),Type,Info,LocalState,State,Res,WF) :- !,
1420		lookup_value_in_store_and_global_sets_wf(Id,Type,LocalState,State,Value,Info,WF),
1421		equal_object_wf(Res,Value,WF).
1422		b_compute_expression2(lazy_lookup_expr(Id),_Type,_Info,LocalState,_State,Res,WF) :- !,
1423		lookup_value_for_existing_id_wf(Id,LocalState,(Trigger,Value),WF), % should normally only occur in LocalState; value introduced by lazy_let
1424		Trigger = pred_true, % force evaluation
1425		equal_object_wf(Res,Value,WF).
1426		b_compute_expression2(lazy_let_expr(Id,AssignmentExpr,Expr),_T,_I,LocalState,State,Value,WF) :-
1427		!,
1428		add_lazy_let_id_and_expression(Id,AssignmentExpr,LocalState,State,NewLocalState,WF),
1429		%Trigger = pred_true, % expressions cannot be delayed !? (TO DO: more refined check)
1430		%block_lazy_compute_expression(Trigger,_,AssignmentExpr,LocalState,State,IdValue,WF,Ai),
1431		b_compute_expression(Expr,NewLocalState,State,Value,WF).
1432		b_compute_expression2(real(Atom),_T,_I,_LocalState,_State,Res,_WF) :- !, construct_real(Atom,Res).
1433		b_compute_expression2(rec(Fields),_T,_I,LocalState,State,Record,WF) :- !,
1434	?	l_compute_field(Fields,LocalState,State,FieldValues,WF),
1435	?	construct_record_wf(FieldValues,Record,WF).
1436		b_compute_expression2(record_field(RecEx,Name),_T,_I,LocalState,State,Value,WF) :- !,
1437	?	b_compute_expression(RecEx,LocalState,State,RecValue,WF),
1438		access_record_wf(RecValue,Name,Value,WF).
1439		b_compute_expression2(freetype_set(Id),_T,_I,_LState,_State,Val,_WF) :- !, Val=freetype(Id). %% NOT COVERED (17)
1440		b_compute_expression2(function(Function,FunArg),Type,Info,LocalState,State,Res,WF) :- !,
1441	?	b_compute_expression_function(Function,FunArg,Type,Info,LocalState,State,Res,WF).
1442		b_compute_expression2(card(b(Arg1,Type,Info)),integer,OuterInfo,LocalState,State,Card,WF) :- !,
1443	?	b_compute_card(Arg1,Type,Info,OuterInfo,LocalState,State,Card,WF).
1444		b_compute_expression2(max(b(Arg1,Type,Info)),integer,_I,LocalState,State,Max,WF) :- !,
1445		b_compute_max(Arg1,Type,Info,LocalState,State,Max,WF).
1446		b_compute_expression2(min(b(Arg1,Type,Info)),integer,_I,LocalState,State,Min,WF) :- !,
1447	?	b_compute_min(Arg1,Type,Info,LocalState,State,Min,WF).
1448		b_compute_expression2(set_extension(Ex),Type,_I,LocalState,State,Res,WF) :- !,
1449	?	b_compute_expressions(Ex,LocalState,State,ExValue,WF),
1450		kernel_call(b_interpreter:convert_list_of_expressions_into_set_wf(ExValue,ValueSet,Type,WF),ExValue,WF, set_extension(Ex)),
1451	?	equal_object_wf(Res,ValueSet,WF).
1452		%kernel_call_convert_list_of_expressions_into_set_wf(ExValue,ValueSet,Type, WF).
1453		%b_compute_expression('ListTermes'(ListOfEx),LocalState,State,ValueSet,WF) :- !,
1454		% /* convert list of expressions of CASE statement into set of elements */
1455		% b_compute_expression(ListOfEx,LocalState,State,Value,WF),
1456		% init_wait_flags(WF),convert_list_of_expressions_into_set_wf(Value,ValueSet,set(any),WF),ground_wait_flags(WF).
1457		b_compute_expression2(sequence_extension(Ex),_T,_I,LocalState,State,ValueSeq,WF) :- !,
1458	?	b_compute_expressions(Ex,LocalState,State,Value,WF),
1459		kernel_call(b_interpreter:convert_list_of_expressions_into_sequence(Value,ValueSeq),Value,WF,sequence_extension(Ex)).
1460		b_compute_expression2(convert_bool(PRED),_T,_I,LocalState,State,Val,WF) :- !, /* B bool(.) operator */
1461	?	b_convert_bool(PRED,LocalState,State,WF,Val).
1462		b_compute_expression2(couple(El1,El2),_T,_I,LocalState,State,Result,WF) :- !, Result = (Val1,Val2),
1463	?	b_compute_expression(El1,LocalState,State,Val1,WF),
1464	?	b_compute_expression(El2,LocalState,State,Val2,WF).
1465		b_compute_expression2(comprehension_set(Parameters,Condition),_T,Info,LocalState,State,Result,WF) :- !,
1466	?	b_compute_comprehension_set(Parameters,Condition,Info,LocalState,State,Result,WF).
1467		b_compute_expression2(recursive_let(TId,TSet),OrigType,OrigInfo,LocalState,State,Result,WF) :- !,
1468		% LET TId = TSet in TSet
1469		( get_texpr_expr(TSet,comprehension_set(Parameters,Condition)) ->
1470		true % if the argument TSet is a comprehension set,
1471		% we just add a recursive parameter
1472		; get_texpr_set_type(TSet,Type) ->
1473		% if not, we construct a new comprehension set {x | x:TSet}
1474		unique_typed_id("_tmparg_",Type,TArg),
1475		Parameters=[TArg],
1476		safe_create_texpr(member(TArg,TSet),pred,Condition)
1477		;
1478		add_internal_error('Expected set as argument to recursive_let',
1479		b_compute_expression2(recursive_let(TId,TSet),OrigType,OrigInfo,LocalState,State,Result,WF)),fail
1480		),
1481		% Generate closure where the references to the recursion are kept
1482		% add recursion ID to parameters to prevent removal of references during compilation
1483		generate_recursive_closure(TId,recursion,[TId|Parameters],Condition,LocalState,State,Closure1,WF),
1484		% add_message(b_interpreter,'Recursive Let for: ',TId,TId),
1485		% remove recursion ID from parameters after compilation
1486		Closure1=closure([_|P],[_|T],Cond),RClosure=closure(P,T,Cond),
1487		% Generate closure where the references to the recursion are kept
1488		generate_recursive_closure(TId,RClosure,Parameters,Condition,LocalState,State,Result,WF).
1489		b_compute_expression2(general_sum(Ids,Condition,Expression),Type,Info,LocalState,State,SumResult,WF) :- !,
1490		b_general_sum_or_mul(Ids,Condition,Expression,Type,Info,LocalState,State,SumResult,WF,sum).
1491		b_compute_expression2(general_product(Ids,Condition,Expression),Type,Info,LocalState,State,MulResult,WF) :- !,
1492		b_general_sum_or_mul(Ids,Condition,Expression,Type,Info,LocalState,State,MulResult,WF,mul).
1493		/* Begin: Extensions for Z */
1494		b_compute_expression2(if_then_else(If,Then,Else),T,_I,LocalState,State,Value,WF) :- !,
1495		opt_push_wait_flag_call_stack_info(WF,b_expr_call(if_test,If),WF2),
1496	?	b_try_check_boolean_expression_wf(If,LocalState,State,WF2,PredRes),
1497		(var(PredRes), can_get_full_fd_value(T), preferences:preference(use_clpfd_solver,true),
1498		always_well_defined(Then), always_well_defined(Else)
1499		% Note: always_well_defined_or_disprover_mode probably not ok, as we evaluate the expressions unconditionally
1500		-> b_clpfd_if_then_else(PredRes,T,Then,Else,LocalState,State,Value,WF)
1501	?	; b_compute_if_then_else(PredRes,Then,Else,LocalState,State,Value,WF)
1502		).
1503		b_compute_expression2(let_expression_global(Ids,AssignmentExprs,Expr),_T,_Info,LocalState,State,Value,WF) :-
1504		% created by bcompiler for operation_call_in_expr
1505		% store variables globally (not in LocalState) to be visible to subsidiary operation_calls
1506		!, set_up_localstate_for_global_let(Ids,AssignmentExprs,LocalState,State,LetState,WF),
1507		b_compute_expression(Expr,LocalState,LetState,Value,WF).
1508		b_compute_expression2(let_expression(Ids,AssignmentExprs,Expr),_T,_I,LocalState,State,Value,WF) :-
1509	?	!, set_up_localstate_for_let(Ids,_ParaValues,AssignmentExprs,LocalState,State,LetState,WF),
1510	?	b_compute_expression(Expr,LetState,State,Value,WF). %% NOT COVERED (30)
1511		b_compute_expression2(freetype_constructor(Id,Case,Expr),_T,_I,LocalState,State,FreeValue,WF) :-
1512		!, FreeValue = freeval(Id,Case,Value),
1513		b_compute_expression(Expr,LocalState,State,Value,WF). %% NOT COVERED (32)
1514		b_compute_expression2(freetype_destructor(Id,Case,Expr),_T,Info,LocalState,State,Value,WF) :-
1515		!, b_compute_expression(Expr,LocalState,State,freeval(Id,VCase,VValue),WF),
1516		check_freetype_case(Id,Case,VCase,VValue,Value,Info,WF).
1517		/* End: Extensions for Z */
1518		b_compute_expression2(assertion_expression(Cond,ErrMsg,Expr),T,Info,LocalState,State,Value,WF) :- !,
1519		opt_push_wait_flag_call_stack_info(WF,
1520		span_predicate(b(assertion_expression(Cond,ErrMsg,b(value(string('')),string,[])),T,Info),LocalState,State),WF2),
1521		% should we use another term for call stack?
1522		(get_preference(disprover_mode,true) -> PredRes = pred_true ; true), % in Disprover mode we know Cond must be true
1523	?	b_try_check_boolean_expression_no_enum_wf(Cond,LocalState,State,WF2,PredRes), % DO NOT ENUM, unless we cannot reify
1524		% does not make sense to enumerate PredRes as with pred_false we get no value anyway
1525		% however, we may get pending co-routines if Cond cannot be reified
1526		( PredRes==pred_false ->
1527		b_compute_assertion_expr(PredRes,Cond,ErrMsg,Expr,LocalState,State,Value,WF2) % will add WD error
1528		; member(prob_annotation(strong_check_with_delay),Info) % delay computing Expr until we are sure Cond is true
1529		-> b_compute_assertion_expr(PredRes,Cond,ErrMsg,Expr,LocalState,State,Value,WF2)
1530	?	; b_compute_expression(Expr,LocalState,State,Value,WF),
1531		add_wd_error_if_false(PredRes,ErrMsg,Cond,span_predicate(Cond,LocalState,State),WF2)
1532		).
1533		b_compute_expression2(multiplication(Arg1,Arg2),integer,Info,LocalState,State,Value,WF) :-
1534		same_texpr(Arg1,Arg2), !, % is less useful when CLPFD is already turned on, calls square(Arg1,Value,WF)
1535		b_compute_expression(Arg1,LocalState,State,SV1,WF),
1536		unary_kernel_call(kernel_objects,square,SV1,Value,WF,multiplication(Arg1,Arg1),integer,Info).
1537		b_compute_expression2(image(Relation,Set),_EType,Info,LocalState,State,Value,WF) :-
1538		special_operator_for_image(Relation,Kind,Args),
1539		% we have closure1(Rel)[Set] or similar -> avoid computing full closure
1540		!,
1541		opt_push_wait_flag_call_stack_info(WF,b_operator_call(image,[Relation,SV],Info),WF2),
1542	?	b_compute_expression(Set,LocalState,State,SV,WF2),
1543	?	b_compute_expressions(Args,LocalState,State,EArgs,WF2),
1544	?	kernel_call(bsets_clp:image_for_special_operator(Kind,EArgs,SV,Value,WF2),[SV|EArgs],WF2,image(Relation,Set)).
1545		b_compute_expression2(external_function_call(FunName,Args),EType,Info,LocalState,State,Value,WF) :-
1546		!,
1547	?	b_compute_expressions(Args, LocalState,State, EvaluatedArgs, WF),
1548		push_wait_flag_call_stack_info(WF,external_call(FunName,EvaluatedArgs,Info),WF2),
1549	?	call_external_function(FunName,Args,EvaluatedArgs,Value,EType,Info,WF2).
1550		b_compute_expression2(Expression,EType,Info,LocalState,State,Res,WF) :-
1551		is_set_type(EType,Type),
1552		/* avoid evaluating certain expensive expressions:
1553		convert them into symbolic closures and expand only if really required */
1554		functor(Expression,UnOp,1),
1555		symbolic_closure_unary_operator(UnOp),
1556		/* TO DO: UNFOLD THIS OR WRAP in CONSTRUCTOR */
1557		arg(1,Expression,BType),
1558		!, %preferences:get_preference(convert_types_into_closures,true),!,
1559		% print_message(delayed_un_op(UnOp,BType)),
1560	?	b_compute_expression(BType,LocalState,State,ArgValue,WF),
1561		( do_not_keep_symbolic_unary(UnOp,ArgValue),
1562		unary_function(UnOp,Module,KernelFunction) ->
1563		/* special treatment for empty set or other situations: no need to keep symbolic */
1564	?	unary_kernel_call(Module,KernelFunction,ArgValue,Res,WF,Expression,EType,Info)
1565		;
1566		get_texpr_type(BType,ArgType),
1567		create_texpr(value(ArgValue),ArgType,[],TValue),
1568		ClosureSetExpression =.. [UnOp,TValue],
1569		construct_member_closure('_zzzz_unary',Type,Info,ClosureSetExpression,Value),
1570	?	((unop_to_be_marked_as_symbolic(UnOp,ArgValue) ; member(prob_annotation('SYMBOLIC'),Info)) ->
1571		mark_closure_as_symbolic(Value,SValue),
1572		equal_object_wf(Res,SValue,WF)
1573		; equal_object_wf(Res,Value,WF))
1574
1575		).
1576		b_compute_expression2(Expression,EType,Info,LocalState,State,Res,WF) :-
1577		is_set_type(EType,Type),
1578		/* avoid evaluating certain expensive expressions:
1579		convert them into symbolic closures and expand only if really required */
1580		functor(Expression,BinOp,2),
1581		arg(1,Expression,BType1),
1582		arg(2,Expression,BType2),
1583		kernel_mappings:symbolic_closure_binary_operator(BinOp),
1584		!,
1585		%preferences:get_preference(convert_types_into_closures,true),!,
1586	?	b_compute_expression(BType1,LocalState,State,ArgValue1,WF),
1587		(binary_arg1_determines_value(BinOp,ArgValue1,DetResult)
1588		-> /* print(det(BinOp,ArgValue1)),nl, */
1589		equal_object_wf(Res,DetResult,b_compute_expression2(BinOp),WF)
1590		; b_compute_expression(BType2,LocalState,State,ArgValue2,WF),
1591		% print_message(delayed_bin_op(BinOp,ArgValue1,ArgValue2)),
1592		(is_definitely_empty(BinOp,ArgValue1,ArgValue2)
1593		-> empty_set(Res)
1594		; if(do_not_keep_symbolic(BinOp,ArgValue1,ArgValue2,ERes,WF),
1595		% then:
1596		equal_object_wf(Res,ERes,b_compute_expression2(BinOp),WF),
1597		% else:
1598		(get_texpr_type(BType1,TypeArg1), create_texpr(value(ArgValue1),TypeArg1,[],TArg1),
1599		get_texpr_type(BType2,TypeArg2), create_texpr(value(ArgValue2),TypeArg2,[],TArg2),
1600		ClosureSetExpression =.. [BinOp,TArg1,TArg2],
1601		construct_member_closure('_zzzz_unary',Type,Info,ClosureSetExpression,Value),
1602		% print('Constructed Symbolic Closure : '), translate:print_bvalue(Value),nl,
1603	?	(binop_to_be_marked_as_symbolic(BinOp,ArgValue1,ArgValue2) ->
1604		mark_closure_as_symbolic(Value,SValue),
1605		equal_object_wf(Res,SValue,WF)
1606	?	; equal_object_wf(Res,Value,WF))
1607		)
1608		) % if
1609		)
1610		).
1611		b_compute_expression2(Expression,Type,Info,LocalState,State,Value,WF) :-
1612		functor(Expression,Op,1),
1613		unary_function(Op,Module,KernelFunction),
1614		arg(1,Expression,Arg1),!,
1615		%opt_push_wait_flag_call_stack_info(WF,b_operator_arg_evaluation(Op,1,[SV1],Arg1),WF1),
1616	?	b_compute_expression(Arg1,LocalState,State,SV1,WF),
1617	?	unary_kernel_call(Module,KernelFunction,SV1,Value,WF,Expression,Type,Info).
1618		b_compute_expression2(Expression,Type,Info,LocalState,State,Value,WF) :-
1619		functor(Expression,Op,2),
1620		binary_function(Op,Module,KernelFunction),
1621		arg(1,Expression,Arg1),
1622		arg(2,Expression,Arg2),!,
1623		%opt_push_wait_flag_call_stack_info(WF,b_operator_arg_evaluation(Op,1,[SV1,_],Arg1),WF1),
1624	?	b_compute_expression(Arg1,LocalState,State,SV1,WF),
1625		(binary_arg1_determines_value(Op,SV1,Result) % we could disable this if find_abort_values=true or if SV1 not guaranteed to be wd
1626		->
1627		equal_object_wf(Value,Result,b_compute_expression2(Op),WF)
1628	?	; b_compute_expression(Arg2,LocalState,State,SV2,WF),
1629	?	binary_kernel_call(Module,KernelFunction,SV1,SV2,Value,WF,Expression,Type,Info)
1630		).
1631		b_compute_expression2(operation_call_in_expr(Operation,Parameters),_T,Info,LocalState,State,Value,WF) :-
1632		!, def_get_texpr_id(Operation,op(OperationName)),
1633		% TODO: check that this is a query operation; probably done in type checker
1634		b_execute_operation_in_expression(OperationName,LocalState,State,Parameters,Value,Info,WF).
1635		b_compute_expression2(E,T,Info,_L,_S,_R,_WF) :-
1636		(T==pred -> add_internal_error('Uncovered expression; looks like a predicate in the wrong place: ',b(E,T,Info))
1637		; T==subst -> add_internal_error('Uncovered expression; looks like a substitution in the wrong place: ',b(E,T,Info))
1638		; requires_cleanup_pre(E) -> add_internal_error('Non-cleaned up ambiguous expression: ',b(E,T,Info))
1639		; add_internal_error('Uncovered expression: ',b(E,T,Info))
1640		),
1641		print_functor(E), print(' : '), print(T),nl,fail.
1642
1643		requires_cleanup_pre(mult_or_cart(_,_)).
1644		requires_cleanup_pre(minus_or_set_subtract(_,_)).
1645
1646		make_couplise([A],R) :- !,R=A.
1647		make_couplise([A,B],R) :- !,R=(A,B).
1648		make_couplise([A,B|Rest],Result) :- !,
1649		make_couplise([(A,B)|Rest],Result).
1650		make_couplise(A,_) :- add_internal_error('Illegal operation call result:',A),fail.
1651
1652		% ---
1653
1654
1655		% check if a symbolic_closure_unary_operator result should be marked with prob_annotation(SYMBOLIC)
1656		% because direct sub-args are marked SYMBOLIC
1657		unop_to_be_marked_as_symbolic(UnOp,Value) :- nonvar(Value),
1658	?	to_be_marked_as_symbolic_aux(UnOp,Value).
1659		to_be_marked_as_symbolic_aux(struct,rec(Fields)) :- !,
1660	?	member(field(_,SymbolicClosure),Fields),
1661	?	is_symbolic_closure(SymbolicClosure).
1662		%to_be_marked_as_symbolic_aux(pow_subset,SymbolicClosure) :- is_symbolic_closure(SymbolicClosure).
1663		%to_be_marked_as_symbolic_aux(pow1_subset,SymbolicClosure) :- is_symbolic_closure(SymbolicClosure).
1664	?	to_be_marked_as_symbolic_aux(_,SymbolicClosure) :- is_symbolic_closure(SymbolicClosure).
1665
1666		% check if a symbolic_closure_binary_operator result should be marked with prob_annotation(SYMBOLIC)
1667		% because direct sub-args are marked SYMBOLIC
1668		binop_to_be_marked_as_symbolic(interval,_,_) :- !, fail.
1669		%binop_to_be_marked_as_symbolic(overwrite,_,_) :- !, true. % TO DO: fix by detecting infinite <+ closures
1670	?	binop_to_be_marked_as_symbolic(set_subtraction,ArgVal1,_) :- !, is_symbolic_closure(ArgVal1).
1671		binop_to_be_marked_as_symbolic(intersection,ArgVal1,ArgVal2) :-
1672	?	(finite_reasonably_sized_set(ArgVal1) ; finite_reasonably_sized_set(ArgVal2)), !,
1673		fail. % intersection is finite and reasonably sized
1674	?	binop_to_be_marked_as_symbolic(_,ArgVal1,_) :- is_symbolic_closure(ArgVal1).
1675	?	binop_to_be_marked_as_symbolic(_,_,ArgVal2) :- is_symbolic_closure(ArgVal2).
1676		% ---
1677
1678		% check if we have a finite known set that can be reasonably represented
1679		% see small_known_set/1 is kernel_mappings
1680		finite_reasonably_sized_set(AVL) :- nonvar(AVL), AVL=avl_set(_). % already expanded; so it can be represented in memory
1681		finite_reasonably_sized_set(Closure) :- nonvar(Closure),
1682		custom_explicit_sets:is_interval_closure(Closure,From,To), integer(From), integer(To),
1683		1+To-From < 250000. % what value should we use here?
1684
1685		lazy_compute_expression(TRIGGER,AssignmentExpr,LocalState,State,IdValue,WF,Ai) :-
1686		get_enumeration_finished_wait_flag(WF,F),
1687		block_lazy_compute_expression(TRIGGER,F,AssignmentExpr,LocalState,State,IdValue,WF,Ai).
1688
1689		:- block block_lazy_compute_expression(-,-,?,?,?, ?,?,?).
1690		block_lazy_compute_expression(TRIGGER,_F,_AssignmentExpr,_LocalState,_State,_IdValue,_WF,_Ai) :-
1691		var(TRIGGER),!.
1692		block_lazy_compute_expression(pred_true,_,AssignmentExpr,LocalState,State,IdValue,WF,Ai) :-
1693		AssignmentExpr = b(Expr,Type,Infos),
1694		(Type \== pred -> b_compute_expression2(Expr,Type,Infos,LocalState,State,IdValue,WF)
1695		; IdValue == pred_true -> b_test_boolean_expression2(Expr,Infos,LocalState,State,WF,Ai,_)
1696		; IdValue == pred_false -> b_not_test_boolean_expression2(Expr,Infos,LocalState,State,WF,Ai,_)
1697		; b_check_boolean_expression(AssignmentExpr,LocalState,State,WF,PredVal,Ai,_) -> IdValue = PredVal
1698		; % reification of check_boolean_expression failed:
1699		b_try_check_failed(AssignmentExpr,LocalState,State,'$ENUMERATION',WF,IdValue,'$GENERATE_ON_DEMAND')
1700		).
1701		block_lazy_compute_expression(pred_false,_,_AssignmentExpr,_LocalState,_State,[],_WF,_Ai). % maybe generate any value ??
1702
1703		% ---
1704
1705		:- block add_wd_error_if_false(-,?,?,?,?).
1706		add_wd_error_if_false(pred_true,_,_,_,_).
1707		add_wd_error_if_false(pred_false,ErrMsg,Cond,Span,WF) :-
1708		translate_bexpression_with_limit(Cond,100,CS),
1709		%(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),
1710		add_wd_error_span(ErrMsg,CS,Span,WF).
1711
1712		:- block b_compute_assertion_expr(-,?,?,?,?,?,?,?).
1713		b_compute_assertion_expr(pred_false,Cond,ErrMsg,_Expr,LocalState,State,_Value,WF) :-
1714		translate_bexpression_with_limit(Cond,100,CS),
1715		add_wd_error_span(ErrMsg,CS,span_predicate(Cond,LocalState,State),WF).
1716		b_compute_assertion_expr(pred_true,_Cond,_ErrMsg,Expr,LocalState,State,Value,WF) :-
1717		b_compute_expression(Expr,LocalState,State,Value,WF).
1718
1719		% ---
1720
1721
1722		:- use_module(kernel_tools,[ground_value/1]).
1723		% compute function application:
1724		b_compute_expression_function(Function,FunArg,Type,Info,LocalState,State,Res,WF) :-
1725		preferences:preference(find_abort_values,false), % below we do not check, e.g., if set extension is really a function
1726		is_extension_function(Function,FInfo,ExFun), !,
1727		/* a set extension applied to an argument: in some cases we can can first evaluate the argument,
1728		and then avoid having to compute the set_extension for all non-matching args */
1729		opt_push_wait_flag_call_stack_info(WF,function_call(Function,ArgValue,Info),WF2), % only push call_stack in TRACE_INFO mode
1730		b_compute_expression(FunArg,LocalState,State,ArgValue,WF2),
1731		% TO DO : should we only do this if ArgValue is known ?? otherwise the standard treatment is better ??
1732		% Note: b_compiler has a special rule to not remove this optimisation
1733		Span = span_predicate(b(function(Function,FunArg),Type,Info),LocalState,State),
1734		((memberchk(contains_wd_condition,FInfo) ; % relevant for test 1302; but machine seems to contain real WD error
1735		preferences:preference(use_clpfd_solver,false) ;
1736		ground_value(ArgValue))
1737		-> b_apply_function_set_extension(ExFun,ArgValue,LocalState,State,Res,WF2,Span)
1738		; /* the standard treatment can infer information about the result,... in clpfd_mode */
1739		b_compute_expression(Function,LocalState,State,FValue,WF),
1740		get_texpr_type(Function,FunctionType),
1741		kernel_call_apply_to(FValue,ArgValue,Res,FunctionType,Span,WF2)).
1742		%b_compute_expression_function(b(comprehension_set(Parameters,Condition),_,SInfo),Arg,Type,Info,LocalState,State,Value,WF) :- !,
1743		% b_compute_comprehension_set_symbolic(Parameters,Condition,SInfo,LocalState,State,FValue,WF),
1744		% b_compute_expression(Arg,LocalState,State,ArgValue,WF),
1745		% Span = span_predicate(b(function(Function,Arg),Type,Info),LocalState,State),
1746		% get_texpr_type(Function,FunctionType),
1747		% kernel_call_apply_to(FValue,ArgValue,Value,FunctionType,Span,WF).
1748		b_compute_expression_function(Function,FunArg,_Type,Info,LocalState,State,Value,WF) :-
1749		special_operator_for_image(Function,Kind,Args),!, % detect e.g. iterate(rel,k)(x) or closure1
1750		opt_push_wait_flag_call_stack_info(WF,function_call(Function,ArgValue,Info),WF2),
1751		b_compute_expression(FunArg,LocalState,State,ArgValue,WF2),
1752		b_compute_expressions(Args,LocalState,State,EArgs,WF2),
1753		kernel_call(bsets_clp:apply_fun_for_special_operator(Kind,EArgs,ArgValue,Value,WF2,Info),
1754		[ArgValue|EArgs],WF2,function(Function,FunArg)).
1755		b_compute_expression_function(Function,Arg,Type,Info,LocalState,State,Value,WF) :-
1756		opt_push_wait_flag_call_stack_info(WF,function_call(Function,ArgValue,Info),WF2),
1757	?	b_compute_expression(Function,LocalState,State,FValue,WF2),
1758	?	b_compute_expression(Arg,LocalState,State,ArgValue,WF2),
1759		Span = span_predicate(b(function(Function,Arg),Type,Info),LocalState,State),
1760		get_texpr_type(Function,FunctionType),
1761		% TODO: do we still need the span predicate when we have the function_call call_stack infos?
1762	?	kernel_call_apply_to(FValue,ArgValue,Value,FunctionType,Span,WF2).
1763
1764
1765		:- use_module(bsyntaxtree,[get_set_type/2,is_set_type/2]).
1766		:- use_module(kernel_cardinality_attr,[finite_cardinality_as_int_with_type_wf/5]).
1767		b_compute_card(Arg1,Type,Info,OuterInfo,LocalState,State,Card,WF) :-
1768	?	b_compute_card2(Arg1,Type,Info,OuterInfo,LocalState,State,Card,WF),
1769		% maybe we should move this code below inside kernel_objects ??
1770		(ground(Card) -> true
1771		; get_set_type(Type,SetElType), % TO DO: only needed for cardinality_of_set_extension_list
1772	?	kernel_objects:max_cardinality(SetElType,MaxCard), % this could be precomputed statically
1773		(number(MaxCard) -> kernel_objects:in_nat_range(Card,int(0),int(MaxCard))
1774		; kernel_objects:greater_than_equal(Card,int(0)) % not sure this is required
1775		)
1776		).
1777		b_compute_card2(set_extension(Ex),_,_,_,LocalState,State,Card,WF) :- !,
1778		b_compute_expressions(Ex,LocalState,State,ExValue,WF),
1779		kernel_objects:cardinality_of_set_extension_list(ExValue,Card,WF).
1780		b_compute_card2(range(F),_,_,_,LocalState,State,Card,WF) :- !,
1781		b_compute_expression(F,LocalState,State,SV1,WF),
1782		kernel_objects:cardinality_of_range(SV1,Card,WF).
1783		b_compute_card2(comprehension_set(Parameters,Condition),Type,Info,OuterInfo,LocalState,State,Card,WF) :- !,
1784		get_set_type(Type,SetElType),
1785		% ensure that we keep the closure and don't expand it:
1786	?	b_compute_comprehension_set_symbolic(Parameters,Condition,Info,LocalState,State,SV1,WF),
1787	?	kernel_mappings:must_succ_kernel_call(
1788		kernel_cardinality_attr:finite_cardinality_as_int_with_type_wf(SV1,SetElType,OuterInfo,Card,WF),SV1,WF,card).
1789		% TO DO: treat comprehension set + things like card({x|x>1 & x<2**e & x mod 2 = 0}) = 0
1790		b_compute_card2(Arg1,Type,Info,OuterInfo,LocalState,State,Card,WF) :-
1791		get_set_type(Type,SetElType),
1792		b_compute_expression2(Arg1,Type,Info,LocalState,State,SV1,WF),
1793	?	kernel_mappings:must_succ_kernel_call(
1794		kernel_cardinality_attr:finite_cardinality_as_int_with_type_wf(SV1,SetElType,OuterInfo,Card,WF),SV1,WF,card).
1795
1796		b_compute_max(set_extension(Ex),_,Info,LocalState,State,Max,WF) :- !,
1797		b_compute_expressions(Ex,LocalState,State,ExValue,WF),
1798		kernel_objects:maximum_of_set_extension_list(ExValue,Max,Info,WF).
1799		b_compute_max(Arg1,Type,Info,LocalState,State,Max,WF) :-
1800		b_compute_expression2_symbolic(Arg1,Type,Info,LocalState,State,SV1,WF),
1801		kernel_mappings:must_succ_kernel_call(kernel_objects:maximum_of_set(SV1,Max,Info,WF),SV1,WF,max).
1802
1803		b_compute_min(set_extension(Ex),_,Info,LocalState,State,Min,WF) :- !,
1804		b_compute_expressions(Ex,LocalState,State,ExValue,WF),
1805		kernel_objects:minimum_of_set_extension_list(ExValue,Min,Info,WF).
1806		/* doesnot really buy a lot: */
1807		/*b_compute_min(union(Arg1,Arg2),_,Info,LocalState,State,Min,WF) :-
1808		Arg1 = b(set_extension(Ex),Type1,Info1),
1809		!,
1810		b_compute_min(set_extension(Ex),Type1,Info1,LocalState,State,Min1,WF),
1811		b_compute_expression(Arg2,LocalState,State,SV2,WF),
1812		b_compute_min2(SV2,Min1,Min,Info,WF).
1813		:- block b_compute_min2(-,?,?,?,?).
1814		b_compute_min2([],Min1,Res,_,_WF) :- !, Res=Min1.
1815		b_compute_min2(SV1,Min1,Res,Info,WF) :-
1816		kernel_mappings:must_succ_kernel_call(kernel_objects:minimum_of_set(SV1,Min2,Info,WF),SV1,WF,min),
1817		min(Min1,Min2,Res).
1818		min(int(A),int(B),int(Res)) :- kernel_objects:minimum(A,B,Res). */
1819		b_compute_min(Arg1,Type,Info,LocalState,State,Min,WF) :-
1820		b_compute_expression2_symbolic(Arg1,Type,Info,LocalState,State,SV1,WF),
1821	?	kernel_mappings:must_succ_kernel_call(kernel_objects:minimum_of_set(SV1,Min,Info,WF),SV1,WF,min).
1822
1823		generate_recursive_closure(TRecId,RecValue,Parameters,Condition,LocalState,State,Result,WF) :-
1824		get_texpr_id(TRecId,RecId),
1825		add_var_to_localstate(RecId,RecValue,LocalState,State1),
1826		debug_println(9,generating_recursive_closure(RecId,Parameters)),
1827		b_generate_rec_closure_aux(RecId,Parameters,Condition,State1,State,RClosure1,WF),
1828		mark_closure_as_recursive(RClosure1,RClosure2),
1829		mark_closure(RClosure2,[recursive(TRecId)],Result),
1830		( debug_mode(off) -> true
1831		; ground_value(Result) -> true
1832		; term_variables(Result,TV),
1833		add_message(b_interpreter,'non-ground closure generated: ',TV:Result,Condition)
1834		).
1835		% a variation of b_generate_closure
1836		b_generate_rec_closure_aux(RecId,Parameters,Condition,LocalState,State,Result,WF) :-
1837		split_names_and_types(Parameters,Names,Types),
1838		construct_closure(Names,Types,ClosurePred,Result),
1839		% now add RecId to parameters to prevent looking up recursive calls
1840		b_compiler:b_compile(Condition,[RecId|Names],LocalState,State,ClosurePred,WF).
1841
1842		% check if a freetype value has the expected case, if not
1843		% generate a WD-error
1844		check_freetype_case(Id,Case,VCase,Inner,Value,Info,WF) :-
1845		get_enumeration_finished_wait_flag(WF,F),
1846		check_freetype_case2(Id,Case,VCase,Inner,Value,Info,F,WF).
1847		:- block check_freetype_case2(?,?,-,?,?,?,-,?).
1848		check_freetype_case2(Id,Case,VCase,Inner,Value,Info,_F,WF) :-
1849		( nonvar(VCase) ->
1850		( Case=VCase -> equal_object_wf(Inner,Value,check_freetype_case2,WF)
1851		;
1852		ajoin(['cannot apply destructor for data type ',Id,
1853		', expected constructor ',Case,', but got: '],Msg),
1854		add_wd_error_set_result(Msg,VCase,Inner,Value,Info,WF))
1855		; % the computation has finished without value,
1856		true). % just drop the check
1857
1858		% check if we have a set_extension argument representing an explicit function
1859		% {a |-> f1, b |-> f2, ...} or [f1,f2]
1860		is_extension_function(b(A,_,Info),Info,C) :- is_extension_function_aux(A,C).
1861		is_extension_function_aux(set_extension(Ex),CaseList) :- is_set_extension_function(Ex,CaseList).
1862		is_extension_function_aux(sequence_extension(Ex),CaseList) :- is_sequence_extension_function(Ex,1,CaseList).
1863		is_set_extension_function([],[]).
1864		is_set_extension_function([b(Couple,TC,_)|T],[case(A,B)|ST]) :- is_couple(Couple,TC,A,B),
1865		is_set_extension_function(T,ST).
1866		is_sequence_extension_function([],_,[]).
1867		is_sequence_extension_function([B|T],Nr,[case(b(value(int(Nr)),integer,[]),B)|ST]) :- N1 is Nr+1,
1868		is_sequence_extension_function(T,N1,ST).
1869
1870		is_couple(couple(A,B),_,A,B).
1871		is_couple(value((VA,VB)),couple(TA,TB), b(value(VA),TA,[]), b(value(VB),TB,[])).
1872
1873		:- use_module(kernel_equality,[equality_objects_wf/4]).
1874		b_apply_function_set_extension([],FunArgVal,_LocalState,_State,_Res,WF,Span) :-
1875		add_wd_error_span('Function applied outside of domain (#8): ','@fun'(FunArgVal,[]),Span,WF).
1876		b_apply_function_set_extension([case(A,B)|T],FunArgVal,LocalState,State,Res,WF,Span) :-
1877		b_compute_expression(A,LocalState,State,AVal,WF),
1878		equality_objects_wf(AVal,FunArgVal,EqRes,WF),
1879		% TO DO: if Res is known, we can call equality_objects(BVal,Res,ResEqRes)
1880	?	b_apply_function_set_extension_aux(EqRes,B,T,FunArgVal,LocalState,State,Res,WF,Span).
1881
1882		:- block b_apply_function_set_extension_aux(-,?,?,?, ?,?,?,?,?).
1883		b_apply_function_set_extension_aux(pred_true,B,_T,_FunArgVal,LocalState,State,Res,WF,_Span) :-
1884		b_compute_expression(B,LocalState,State,BVal,WF), %print(value(BVal)),nl,
1885	?	equal_object_wf(BVal,Res,b_apply_function_set_extension_aux,WF).
1886		b_apply_function_set_extension_aux(pred_false,_B,T,FunArgVal,LocalState,State,Res,WF,Span) :-
1887	?	b_apply_function_set_extension(T,FunArgVal,LocalState,State,Res,WF,Span).
1888
1889
1890		% --------------------- SIGMA & PI ------------------------
1891		:- use_module(bsyntaxtree,[is_membership_or_equality/3,same_id/3]).
1892		/* first clause: try to do a specific treatment for formulas of the form SIGMA(ID).(ID:SET|EXPR) */
1893		/* Advantage: will not delay as long before computing comprehension_set SET ; see test 1312 */
1894		b_general_sum_or_mul([TID],Condition,Expression,Type,_Info,LocalState,State,SumResult,WF,SUMorMUL) :-
1895		is_membership_or_equality(Condition,MID,SET),
1896		same_id(TID,MID,_),!,
1897		b_compute_expression(SET,LocalState,State,SETResult,WF),
1898		b_general_sum_or_mul_over_set([TID],SETResult,Expression,Type,LocalState,State,SumResult,WF,SUMorMUL).
1899		b_general_sum_or_mul(Ids,Condition,Expression,Type,Info,LocalState,State,SumMulResult,WF,SUMorMUL) :-
1900		b_compute_comprehension_set(Ids,Condition,Info,LocalState,State,SETResult,WF),
1901		(var(SETResult) -> perfmessagecall(sigma_pi_not_expanded_or_reified(SUMorMUL),
1902		translate:print_bexpr(Condition),Condition) ; true),
1903		b_general_sum_or_mul_over_set(Ids,SETResult,Expression,Type,LocalState,State,SumMulResult,WF,SUMorMUL).
1904
1905
1906		:- block b_general_sum_or_mul_over_set(?,-, ?,?,?,?, ?,?,?).
1907		b_general_sum_or_mul_over_set([TID],SETResult,Expression,Type,_LS,_S,SumResult,WF,SUMorMUL) :-
1908		Type=integer, % TO DO: also for real
1909		get_texpr_id(Expression,ID), % check if we just sum the elements of the list SIGMA(x).(x:S|x)
1910		get_texpr_id(TID,ID),
1911	?	sum_or_mul_of_explicit_set(SETResult,SUMorMUL,R),!,
1912		equal_object_wf(SumResult,R,b_general_sum_or_mul_over_set,WF).
1913		b_general_sum_or_mul_over_set(IDs,SETResult,Expression,Type,LocalState,State,SumResult,WF,SUMorMUL) :-
1914		expand_custom_set_to_list_wf(SETResult,ESETResult,_Done,b_general_sum_or_mul_over_set,WF),
1915		b_sum_or_mul_over_list(ESETResult,IDs,Expression,Type,LocalState,State,SumResult,WF,SUMorMUL).
1916
1917		b_sum_or_mul_over_list(L,IDs,Expr,Type,LS,State,Result,WF,SUMorMUL) :-
1918		get_acc_base(SUMorMUL,Type,Acc),
1919		(Type = integer -> get_wait_flag0(WF,WF0) ; true), % for real: delay until values known
1920		b_sum_or_mul_over_list_acc(L,IDs,Expr,Type,LS,State,Acc,Result,WF,SUMorMUL,WF0).
1921
1922		:- block b_sum_or_mul_over_list_acc(-, ?, ?,?,?,?,?, ?,?,?,?).
1923		% better if list is fully known: no constraint propagation performed during computation !
1924		% for example: SIGMA(x).(x:{-1} \/ 1..30000|x+1) goes down from 2050 ms to 1210 ms
1925		b_sum_or_mul_over_list_acc([],_,_,Type,_,_,Acc,Result,_WF,_SUMorMUL,_) :-
1926		get_acc_result(Type,Acc,Result).
1927		b_sum_or_mul_over_list_acc([H|T],IDs,Expr,Type,LocalState,State,Acc,Result,WF,SUMorMUL,WF0) :-
1928		add_typed_vars_to_localstate(IDs,H,LocalState,NewLocalState),
1929		b_compute_expression(Expr,NewLocalState,State,HExprVal,WF),
1930		b_sum_or_mul_over_list_acc2(HExprVal,T,IDs,Expr,Type,LocalState,State,Acc,Result,WF,SUMorMUL,WF0).
1931
1932		:- block b_sum_or_mul_over_list_acc2(?,-, ?, ?,?,?,?,?, ?,?,?,?),
1933		b_sum_or_mul_over_list_acc2(?,?, ?, ?,?,?,?,-, ?,?,?,-),
1934		b_sum_or_mul_over_list_acc2(-,?, ?, ?,?,?,?,?, ?,?,?,-). % wait until T nonvar and either Acc & HExprVal known or WF0 set
1935		% purpose: try and remain in non-CLPFD mode as long as possible to avoid overflows,... (see eg. test 1642, 1708)
1936		b_sum_or_mul_over_list_acc2(HExprVal,T,IDs,Expr,Type,LocalState,State,Acc, Result,WF,SUMorMUL,WF0) :-
1937		(nonvar(T),nonvar(Acc),ground(HExprVal)
1938		-> % we can continue computing the system without constraint propagation; is faster
1939		get_value(Type,HExprVal,HVal),
1940		compose_acc(SUMorMUL,Acc,HVal,NewAcc),
1941		b_sum_or_mul_over_list_acc(T,IDs,Expr,Type,LocalState,State,NewAcc,Result,WF,SUMorMUL,WF0)
1942		; T==[], number(Acc), get_acc_base(SUMorMUL,Type,Acc) ->
1943		/* we have just a single element left and no operator has to be applied -> no need for clpfd treatment */
1944		equal_object_wf(HExprVal,Result,b_sum_or_mul_over_list_acc)
1945		; Type=real -> % no CLP(FD) treatment possible yet
1946		when(ground(HExprVal),
1947		b_sum_or_mul_over_list_acc2(HExprVal,T,IDs,Expr,Type,LocalState,State,Acc, Result,WF,SUMorMUL,WF0))
1948		; init_clp_acc(SUMorMUL,HExprVal,int(Acc),CLPAccumulator),
1949		b_sum_or_mul_over_list_clp(T,IDs,Expr,LocalState,State,CLPAccumulator,Result,WF,SUMorMUL)
1950		).
1951
1952		% add set comprehension solution ValueForTypedIDs as individual values for every TypedIDs to LocalState
1953		add_typed_vars_to_localstate(TypedIDs,ValueForTypedIDs,LocalState,NewLocalState) :-
1954		(flatten_pairs(TypedIDs,ValueForTypedIDs,ValAsList),
1955		add_typed_vars_to_localstate_aux(TypedIDs,ValAsList,LocalState,R)
1956		-> NewLocalState = R
1957		; add_internal_error('Call failed: ',add_typed_vars_to_localstate(TypedIDs,ValueForTypedIDs,LocalState,NewLocalState)),
1958		fail
1959		).
1960		% set comprehension results for {a,b,c|P} are nested like this ((a,b),c)
1961		% first argument only used for length (to know how deep the pairs are nested)
1962		flatten_pairs(L,Pairs,FlatList) :- flatten_pairs(L,Pairs,FlatList,[]).
1963		flatten_pairs([_],A) --> !, [A].
1964		flatten_pairs([_|T],(A,B)) --> flatten_pairs(T,A) ,[B].
1965		add_typed_vars_to_localstate_aux([],_,LS,LS).
1966		add_typed_vars_to_localstate_aux([TID],[H],LocalState,NewLocalState) :- !,
1967		get_texpr_id(TID,ID), get_texpr_type(TID,TYPE),
1968		add_typed_var_to_localstate(ID,H,TYPE,LocalState,NewLocalState).
1969		add_typed_vars_to_localstate_aux([TID1|Ids],[H1|Hs],LocalState,NewLocalState) :- !,
1970		get_texpr_id(TID1,ID1), get_texpr_type(TID1,TYPE),
1971		add_typed_var_to_localstate(ID1,H1,TYPE,LocalState,LS1),
1972		add_typed_vars_to_localstate_aux(Ids,Hs,LS1,NewLocalState).
1973
1974
1975		:- block b_sum_or_mul_over_list_clp(-, ?, ?,?,?, ?, ?,?,?).
1976		b_sum_or_mul_over_list_clp([],_, _,_,_, Acc, Result,_WF,SUMorMUL) :-
1977		finalise_clp(SUMorMUL,Acc,Result).
1978		b_sum_or_mul_over_list_clp([H|T],IDs,Expr,LocalState,State,Acc, Result,WF,SUMorMUL) :-
1979		add_typed_vars_to_localstate(IDs,H,LocalState,NewLocalState),
1980		b_compute_expression(Expr,NewLocalState,State,HExprVal,WF),
1981		compose_clp(SUMorMUL,HExprVal,Acc,NewAcc),
1982		b_sum_or_mul_over_list_clp(T,IDs,Expr,LocalState,State,NewAcc,Result,WF,SUMorMUL).
1983
1984		get_acc_base(sum,integer,R) :- !, R=0.
1985		get_acc_base(sum,real,0.0).
1986		get_acc_base(mul,integer,R) :- !, R=1.
1987		get_acc_base(mul,real,1.0).
1988		get_acc_result(integer,Nr,int(Nr)).
1989		get_acc_result(real,Nr,Real) :- is_real(Real,Nr).
1990		get_value(integer,int(Val),Val) :- !.
1991		get_value(real,Real,Nr) :- is_real(Real,Nr).
1992
1993		compose_acc(sum,A,B,C) :- C is A+B.
1994		compose_acc(mul,A,B,C) :- C is A*B.
1995		init_clp_acc(sum,int(A),int(B),Res) :- (B==0 -> Res=[A] ; Res=[A,B]). % A always not ground
1996		init_clp_acc(mul,A,B,C) :- times(A,B,C).
1997		compose_clp(sum,int(A),Acc,NewAcc) :- NewAcc = [A|Acc].
1998		compose_clp(mul,A,B,C) :- times(A,B,C).
1999		:- use_module(clpfd_interface,[clpfd_sum/2]).
2000		finalise_clp(sum,Acc,int(Result)) :-
2001		clpfd_sum(Acc,Result). % using clpfd_sum can be much more efficient: no intermediate variables set up
2002		finalise_clp(mul,int(Acc),int(Acc)).
2003
2004		/* for if-then-else in Z: compute Then or Else,
2005		depending on the outcome of the predicate */
2006		:- block b_compute_if_then_else(-,?,?,?,?,?,?).
2007		b_compute_if_then_else(pred_true,Then,_Else,LocalState,State,Value,WF) :-
2008		opt_push_wait_flag_call_stack_info(WF,b_expr_call(if_then_body,Then),WF2),
2009	?	b_compute_expression(Then,LocalState,State,Value,WF2).
2010		b_compute_if_then_else(pred_false,_Then,Else,LocalState,State,Value,WF) :-
2011		opt_push_wait_flag_call_stack_info(WF,b_expr_call(if_else_body,Else),WF2),
2012	?	b_compute_expression(Else,LocalState,State,Value,WF2).
2013
2014		:- use_module(clpfd_interface,[clpfd_if_then_else/4]).
2015		% a more sophisticated treatment, can also work backwards forcing PredRes
2016		% examples:
2017		% x = IF a<10 THEN 0 ELSE 5 END & x:6..10 & a:1..23
2018		% see must_fail_clpfd_det 132 and 133
2019		% problematic if Else contains recursion; but then we should have WD condition
2020		b_clpfd_if_then_else(PredRes,Type,Then,Else,LocalState,State,Value,WF) :-
2021		get_wait_flag0(WF,WF0),
2022		b_clpfd_if_then_else_block(PredRes,WF0,Type,Then,Else,LocalState,State,Value,WF).
2023		:- block b_clpfd_if_then_else_block(-,-,?,?,?,?,?,?,?).
2024		b_clpfd_if_then_else_block(PredRes,_,Type,Then,Else,LocalState,State,Value,WF) :- var(PredRes),!,
2025		get_full_fd_value(Type,Value,FDValue),
2026		b_compute_expression(Then,LocalState,State,ThenValue,WF),
2027		get_full_fd_value(Type,ThenValue,FDThenValue),
2028		b_compute_expression(Else,LocalState,State,ElseValue,WF),
2029		get_full_fd_value(Type,ElseValue,FDElseValue),
2030		% TO DO: catch CLPFD overflow and use equality_objects
2031		clpfd_if_then_else(PredRes,FDThenValue,FDElseValue,FDValue).
2032		b_clpfd_if_then_else_block(pred_true,_,_Type,Then,_Else,LocalState,State,Value,WF) :-
2033		b_compute_expression(Then,LocalState,State,Value,WF).
2034		b_clpfd_if_then_else_block(pred_false,_,_Type,_Then,Else,LocalState,State,Value,WF) :-
2035		b_compute_expression(Else,LocalState,State,Value,WF).
2036
2037		:- use_module(b_global_sets,[get_global_type_value/3]).
2038		% try and get full_fd_value; true if full value can be translated to CLP(FD) value
2039		get_full_fd_value(global(T),FY,X) :- get_global_type_value(FY,T,X).
2040		get_full_fd_value(integer,int(X),X).
2041		get_full_fd_value(boolean,B,FD) :- kernel_equality:prop_eq_01(B,FD).
2042		% record with single field ?
2043
2044		can_get_full_fd_value(global(_)).
2045		can_get_full_fd_value(integer).
2046		can_get_full_fd_value(boolean).
2047
2048		% a slightly improved version over set_up_localstate (not sure it is really much faster):
2049		add_lazy_let_id_to_local_state(b(identifier(ID),_,_),Trigger,IdValue,LocalState,NewState) :-
2050		% should we delete any old occurence of ID in LocalState?
2051		NewState = [bind(ID,(Trigger,IdValue))|LocalState].
2052
2053		add_lazy_let_id_and_expression(Id,IdExpr,LocalState,InState,NewLocalState,WF) :-
2054		empty_avl(Ai),
2055		add_lazy_let_id_and_expression(Id,IdExpr,LocalState,InState,NewLocalState,WF,Ai).
2056		add_lazy_let_id_and_expression(Id,IdExpr,LocalState,InState,NewLocalState,WF,Ai) :-
2057		add_lazy_let_id_to_local_state(Id,Trigger,IdValue,LocalState,NewLocalState),
2058		lazy_compute_expression(Trigger,IdExpr,LocalState,InState,IdValue,WF,Ai).
2059
2060		/* for let-statements in Z and now in B: expand localstate by new variables and assign
2061		values to them ;
2062		now Expressions are evaluated in state *with* the new identifiers !
2063		*/
2064		%set_up_localstate_for_let_no_reuse(Ids,Exprs,LocalState,State,LetState,WF) :-
2065		% set_up_localstate(Ids,Vars,LocalState,LetState),
2066		% compute_let_expressions(Exprs,Vars,LocalState,State,WF).
2067		set_up_localstate_for_let(Ids,Vars,Exprs,LocalState,State,LetState,WF) :-
2068		set_up_localstate(Ids,Vars,LocalState,LetState),
2069		%external_functions:observe_variables(Ids,Vars),
2070	?	compute_let_expressions(Exprs,Vars,LetState,State,WF).
2071		compute_let_expressions([],[],_,_,_).
2072		compute_let_expressions([Expr|RestExprs],[Var|RestVars],LocalState,State,WF) :-
2073	?	b_compute_expression(Expr,LocalState,State,Value,WF),
2074		equal_object_optimized(Var,Value,compute_let_expressions),
2075	?	compute_let_expressions(RestExprs,RestVars,LocalState,State,WF).
2076
2077		set_up_localstate_for_global_let(Ids,Exprs,LocalState,State,LetState,WF) :-
2078		set_up_localstate(Ids,Vars,State,LetState),
2079		compute_let_expressions(Exprs,Vars,LocalState,LetState,WF).
2080
2081
2082		l_compute_field([],_LS,_S,[],_WF).
2083		l_compute_field([Field|T],LS,S,[FVal|CT],WF) :-
2084	?	b_compute_field(Field,LS,S,FVal,WF),
2085	?	l_compute_field(T,LS,S,CT,WF).
2086
2087		b_compute_field(field(Name,TypeOrVal),LocalState,State,field(Name,TypeOrFieldValue),WF) :-
2088	?	b_compute_expression(TypeOrVal,LocalState,State,TypeOrFieldValue,WF).
2089
2090
2091
2092		:- use_module(b_compiler).
2093
2094		/* :- type bsets_closure +--> closure(list(type(variable_id)),
2095		list(type(basic_type_descriptor)),type(boolean_expression)). */
2096
2097		:- assert_pre(b_interpreter:b_compute_comprehension_set(Parameters,Cond,_Info,LS,State,_R,_WF),
2098		(ground_check(Parameters),
2099		bsyntaxtree:check_if_typed_predicate(Cond),type_check(LS,store),type_check(State,store)) ).
2100
2101		:- assert_post(b_interpreter:b_compute_comprehension_set(_P,_C,_Info,_LS,_State,Val,_WF),
2102		(b_interpreter:value_type(Val))). %, nonvar(Val)
2103
2104
2105		b_compute_comprehension_set_symbolic(Parameters,Condition,Info,LocalState,State,Result,WF) :-
2106		% a version which never expands the generated closure
2107	?	b_generate_closure_if_necessary(Parameters,Condition,LocalState,State,CResult,WF),
2108	?	(member(prob_annotation('SYMBOLIC'),Info)
2109		-> mark_closure_as_symbolic(CResult,CRS),
2110		equal_object_wf(CRS,Result,b_compute_comprehension_set_symbolic,WF)
2111		; equal_object_wf(CResult,Result,b_compute_comprehension_set_symbolic,WF)
2112		).
2113
2114		% we could catch Parameters = [TID], Condition = b(member(b(identifier(ID),_TYPE,_),SET)
2115		b_compute_comprehension_set(Parameters,Condition,Info,LocalState,State,Result,WF) :-
2116	?	b_generate_closure_if_necessary(Parameters,Condition,LocalState,State,CResult,WF),
2117	?	b_compute_comprehension_set_aux(CResult,Info,Result,WF).
2118
2119		:- use_module(clpfd_interface,[catch_clpfd_overflow_call2/2]).
2120		b_compute_comprehension_set_aux(CResult,_,Result,WF) :-
2121		(var(CResult) ; \+ functor(CResult,closure,3) ),!,
2122		equal_object_wf(CResult,Result,b_compute_comprehension_set_aux,WF).
2123		b_compute_comprehension_set_aux(CResult,Info,Result,WF) :-
2124	?	member(prob_annotation('SYMBOLIC'),Info),!,
2125		mark_closure_as_symbolic(CResult,CRS),
2126		equal_object_wf(CRS,Result,b_compute_comprehension_set_aux,WF).
2127		b_compute_comprehension_set_aux(CResult,Info,Result,WF) :-
2128		(preferences:get_preference(convert_comprehension_sets_into_closures,true)
2129		-> \+ definitely_expand_this_explicit_set(CResult)
2130		; dont_expand_symbolic_explicit_set(CResult), % Note: also detects FORCE annotation
2131		perfmessage_wf(symbolic,'Keeping comprehension-set symbolic (use FORCE to override this or increase SYMBOLIC_LIMIT)','',Info,WF)
2132		),!,
2133	?	equal_object_wf(CResult,Result,b_compute_comprehension_set_aux,WF).
2134		b_compute_comprehension_set_aux(CResult,Info,Result,WF) :-
2135		b_expand_compute_comprehension_set(CResult,Info,Result,WF).
2136
2137		b_expand_compute_comprehension_set(CResult,Info,Result,WF) :-
2138		% 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
2139		(preferences:preference(use_smt_mode,false)
2140		-> 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
2141		% only in SMT mode can there be any benefit in expanding a non-ground closure (when it is a lambda closure)
2142		% => hence delay expansion longer, possibly detecting enumeration warnings while expanding
2143		% TO DO: for lambda closures with known domain: expand earlier !
2144		; get_wait_flag(2,b_compute_comprehension_set,WF,WF0)),
2145		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
2146		(var(WF0),var(Result) -> ground_value_check(CResult,CGr) ; true),
2147		block_compute_comprehension_set_aux(CResult,Info,Result,WF,WF0,CGr).
2148
2149		:- block block_compute_comprehension_set_aux(?,?,-,?,-,-).
2150		block_compute_comprehension_set_aux(CResult,Info,Result,WF,_WF0,_CGr) :-
2151		(
2152		nonvar(Result)
2153	?	-> equal_object_wf(CResult,Result,WF) % this may expand CResult or do other tests;
2154		% like emptyness test or symbolic equality;
2155		% if Result=[_|_] then the closure needs to be expanded anyhow, so need to try and keep symbolic
2156		;
2157	?	catch_clpfd_overflow_call2(
2158		on_enumeration_warning_with_continue(expand_only_custom_closure_global(CResult,Expansion,check_no_inf,WF),
2159		% check_no_inf: we know it is not definitely infinite; and we do not want warnings for virtual time-outs
2160		% an enumeration warning occured in the expansion scope: keep closure symbolic after all
2161		% NOTE: for this detection to work it is better to delay until the body is ground (CGr)
2162		% and not use a priority too low for WF0, otherwise Expansion will be var and enum warning may occur later
2163		b_compute_comprehension_set_sym_msg(CResult,Info,Result,WF) % Backup Call in case of enum warning
2164		,
2165		equal_object_wf(Result,Expansion,WF) % TrueContinuation
2166		% instantiating Result can trigger other code which fails and confuses on_enumeration_warning
2167		),
2168		b_compute_comprehension_set_sym(CResult,Result,WF)
2169		) % catch_clpfd_overflow_call2
2170		).
2171
2172		b_compute_comprehension_set_sym_msg(CResult,Info,Result,WF) :- CResult = closure(P,_T,B),
2173		silent_mode(off),
2174		% TO DO: should we check that this closure has not been constructed by ProB, e.g., for UNION ??
2175		% e.g., P = ['__RANGE_LAMBDA__'] what about '_zzzz_unary', '_zzzz_binary', '_prj_arg1__', ...
2176		% also: what if the enumeration warning has a pending_abort_error
2177		!,
2178		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: ',
2179		(contains_info_pos(Info) -> Span=Info ; Span=B),
2180		add_message(b_compute_comprehension_set,Msg,P,Span),
2181		b_compute_comprehension_set_sym(CResult,Result,WF).
2182		b_compute_comprehension_set_sym_msg(CResult,_,Result,WF) :-
2183		b_compute_comprehension_set_sym(CResult,Result,WF).
2184
2185
2186		b_compute_comprehension_set_sym(CResult,Result,WF) :-
2187		mark_closure_as_symbolic(CResult,CRS), % prevent doing the same mistake again
2188		equal_object_wf(Result,CRS,b_compute_comprehension_set_sym,WF).
2189
2190
2191		:- use_module(closures,[construct_closure_if_necessary/4]).
2192		b_generate_forall_closure(Parameters,Condition,LocalState,State,Result,WF) :-
2193		split_names_and_types(Parameters,Names,Types),
2194		construct_closure(Names,Types,ClosurePred1,Result),
2195		(LocalState==[],State==[]
2196		-> ClosurePred = Condition % no lookups can be performed anyway; no need to compile
2197		; b_compiler:b_compile(Condition,Names,LocalState,State,ClosurePred,WF) ),
2198		add_texpr_infos(ClosurePred,[quantifier_kind(forall)],ClosurePred1). % info for call_stack
2199
2200
2201
2202		b_generate_closure_if_necessary(Parameters,Condition,LocalState,State,Result,WF) :-
2203		split_names_and_types(Parameters,Names,Types),
2204	?	b_compiler:b_compile(Condition,Names,LocalState,State,ClosurePred,WF),
2205		%print('COMPILED: '),translate:print_bexpr(ClosurePred),nl,
2206		construct_closure_if_necessary(Names,Types,ClosurePred,Result).
2207
2208
2209		:- public convert_list_of_expressions_into_sequence/2.
2210		convert_list_of_expressions_into_sequence(List,SeqValue) :-
2211		convert_list_of_expressions_into_sequence(List,1,Seq),
2212	?	equal_object_optimized(Seq,SeqValue,convert_list_of_expressions_into_sequence).
2213
2214		convert_list_of_expressions_into_sequence([],_,[]).
2215		convert_list_of_expressions_into_sequence([H|T],Cur,[(int(Cur),H)|ConvT]) :-
2216		C1 is Cur+1,
2217		convert_list_of_expressions_into_sequence(T,C1,ConvT).
2218
2219		convert_list_of_expressions_into_set_wf(ListOfElements,Set,Type,WF) :-
2220		list_of_expressions_is_ground(ListOfElements,Ground,OrderedListOfElements),
2221	?	convert_list_of_expressions_into_set1(Ground,OrderedListOfElements,Set,Type,WF).
2222		convert_list_of_expressions_into_set1(true,ListOfElements,Set,_Type,WF) :- %var(Set),
2223	?	\+ (ListOfElements = [H|_], is_symbolic_closure(H)), % list contains symbolic closures, do not try to expand to avl
2224		% see should_be_converted_to_avl_from_lists ?
2225		!, construct_avl_from_lists_wf(ListOfElements,AVLSet,WF),
2226	?	equal_object_wf(AVLSet,Set,convert_list_of_expressions_into_set1,WF).
2227		convert_list_of_expressions_into_set1(_,Seq,Set,Type,WF) :-
2228	?	kernel_objects:max_cardinality(Type,TypeMaxCard),
2229	?	convert_list_of_expressions_into_set2(Seq,1,[],Set,TypeMaxCard,WF).
2230
2231		% TO DO: sort elements : ground elements first
2232		convert_list_of_expressions_into_set2([],_,Set,Res,_,WF) :-
2233	?	equal_object_wf(Set,Res,convert_list_of_expressions_into_set2,WF).
2234		convert_list_of_expressions_into_set2([H|T],MaxSze,SetSoFar,OutSet,TypeMaxCard,WF) :-
2235		%kernel_objects:basic_type_set(Type,IntSet,MaxSze),
2236		check_set_lists_bounded(IntSet,TypeMaxCard,MaxSze),
2237		% TO DO: optimize; avoid traversing or typing elements over and over again
2238		% maybe add a max. sze argument to add_element
2239		add_element_wf(H,SetSoFar,IntSet,WF), % print(add_el(H,SetSoFar,IntSet)),nl,
2240		% TO DO: check if H in OutSet and keep track of which elements have already been covered in OutSet
2241		%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
2242	?	kernel_objects:lazy_try_check_element_of(H,OutSet,WF),
2243		M1 is MaxSze+1,
2244	?	convert_list_of_expressions_into_set2(T,M1,IntSet,OutSet,TypeMaxCard,WF).
2245
2246
2247		:- use_module(inf_arith).
2248
2249		% check that a set does not exceed a certain bound (to prevent infinite
2250		% or overeager enumeration of sets); Warning: will not check custom_explicit_set sizes
2251		check_set_lists_bounded(Set,TypeMaxCard,Bound) :-
2252		inf_arith:infmin(TypeMaxCard,Bound,Card),
2253		(is_inf_or_overflow_card(Card) -> true
2254		; Card<1 -> empty_set(Set)
2255		; check_set_bounded_aux(Set,Card)).
2256
2257		:- block check_set_bounded_aux(-,?).
2258		check_set_bounded_aux(CustomSet,_) :- is_custom_explicit_set(CustomSet,check_set_bounded_aux),!.
2259		check_set_bounded_aux([],_).
2260		check_set_bounded_aux([_|T],Card) :-
2261		C1 is Card-1,
2262		(C1=0 -> empty_set(T) ; check_set_bounded_aux(T,C1)).
2263
2264
2265
2266		% check if the list can be converted into AVL form; if not: re-order list so that ground elements are present first
2267		list_of_expressions_is_ground([],true,[]).
2268		list_of_expressions_is_ground([E|T],Ground,ResList) :-
2269		(should_be_converted_to_avl(E) -> ResList=[E|RT], list_of_expressions_is_ground(T,Ground,RT)
2270		; Ground=false,
2271		bring_ground_elements_forward(T,[E],ResList)
2272		).
2273
2274		bring_ground_elements_forward([],Acc,Acc).
2275		bring_ground_elements_forward([H|T],Acc,Res) :-
2276		(should_be_converted_to_avl(H) -> Res=[H|RT], bring_ground_elements_forward(T,Acc,RT)
2277		; bring_ground_elements_forward(T,[H|Acc],Res)).
2278
2279		:- use_module(kernel_card_arithmetic,[is_inf_or_overflow_card/1, safe_mul/3]).
2280		% compute cardinality of a list of parameters, such as for forall
2281		parameter_list_cardinality([],1).
2282		parameter_list_cardinality([b(identifier(_),BasicType,_)|T],Res) :-
2283	?	parameter_list_cardinality(T,TCard),
2284		(is_inf_or_overflow_card(TCard) -> Res=TCard
2285	?	; kernel_objects:max_cardinality(BasicType,Card),
2286		safe_mul(Card,TCard,Res)
2287		).
2288		% see also basic_type_list_cardinality, now moved to custom_explicit_sets
2289
2290		b_for_all(Parameters,Infos,LHS,RHS,LocalState,State,WF) :-
2291		get_wait_flag1(for_all(Parameters),WF,LWF), % hack: give total_function,... priority to set up domain/range
2292	?	b_for_all_aux(LWF,Parameters,Infos,LHS,RHS,LocalState,State,WF).
2293
2294		:- block b_for_all_aux(-,?,?,?,?,?,?,?).
2295		b_for_all_aux(_,Parameters,Infos,LHS,RHS,LocalState,State,WF) :-
2296		split_names_and_types(Parameters,Names,Types),
2297	?	b_compile(LHS,Names,LocalState,State,CLHS,WF),
2298	?	b_compile(RHS,Names,LocalState,State,CRHS,WF),
2299	?	b_for_all_aux2(Parameters,Names,Types,Infos,CLHS,CRHS,WF).
2300
2301		:- use_module(kernel_tools,[ground_bexpr/1, ground_bexpr_check/2]).
2302		b_for_all_aux2(_,_,_,_,LHS,RHS,_) :-
2303		(is_falsity(LHS) ; is_truth(RHS)),
2304		!. % quantifier always true
2305		b_for_all_aux2(Parameters,CParameters,CParameterTypes,Infos,LHS,RHS,WF) :-
2306		ground_bexpr(LHS),
2307	?	\+ obvious_enumeration(LHS,CParameters), % if we have an obvious (small) enumeration in the LHS it is often
2308		% better simply to enumerate and check the RHS for every instance
2309		ground_bexpr(RHS), %print(not_exists_forall(Parameters,LHS,RHS)),nl,
2310		!,
2311		b_for_all_find_counter_example(Parameters,CParameters,CParameterTypes,Infos,LHS,RHS,WF).
2312		b_for_all_aux2(Parameters,CParameters,CParameterTypes,Infos,LHS,RHS,WF) :-
2313	?	parameter_list_cardinality(Parameters,ParCard),
2314		peel_implications(Parameters,ParCard,LHS,RHS, LHS2,RHS2),
2315	?	b_for_all_aux3(Parameters,ParCard,CParameters,CParameterTypes,Infos,LHS2,RHS2,WF).
2316
2317		b_for_all_aux3(Parameters,ParCard,CParameters,CParameterTypes,Infos,LHS,RHS,WF) :-
2318		%large_domain(Parameters,ParCard,LHS),
2319		is_infinite_or_very_large_explicit_set(closure(CParameters,CParameterTypes,LHS),10000000),
2320		% the domain is so large that we cannot possibly check all instances
2321		% 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)
2322		!,
2323		perfmessage(forall,'Large forall domain: ',ParCard,Infos),
2324		ground_bexpr_check(LHS,LG),
2325		ground_bexpr_check(RHS,RG),
2326		when((nonvar(LG),nonvar(RG)),
2327		b_for_all_find_counter_example(Parameters,CParameters,CParameterTypes,Infos,LHS,RHS,WF)
2328		).
2329		b_for_all_aux3(Parameters,ParCard,_CP,_,Infos,LHS,RHS,WF) :-
2330		if(expand_forall_quantifier(Parameters,LHS,RHS,Infos,WF,ReificationVariable),
2331		(
2332		perfmessage(good(forall),'Reified forall by expanding into conjunction: ',LHS),
2333		ReificationVariable=pred_true),
2334		( % print(normal_forall(Parameters)),nl,
2335		b_generate_for_all_list_domain1(Parameters,ParCard,LHS,RHS,[],[],AllSolList,NewRHS,WF),
2336		% now check every instance of the expanded domain (AllSolList):
2337	?	expand_forall1(AllSolList,NewRHS,Parameters,WF)
2338		)).
2339
2340
2341		% a treatment of for all where we look for counter examples satisfying LHS & not(RHS)
2342		b_for_all_find_counter_example(Parameters,CParameters,CParameterTypes,Infos,LHS,RHS,WF) :-
2343		% if LHS is Parameters: avl_set(V) then we probably should not apply this rule ?
2344		create_negation(RHS,NegRHS),
2345		conjunct_predicates_with_pos_info(LHS,NegRHS,Pred0),
2346		% format('looking for: ~w ',[CParameters]), translate:print_bexpr(LHS),nl, translate:print_bexpr(NegRHS),nl,
2347		perfmessage(good(forall),translating_forall_into_not_exists(CParameters),LHS),
2348		add_texpr_infos(Pred0,[quantifier_kind(forall)],ClosureBody1), % for call_stack
2349		init_quantifier_wait_flag(WF,not(forall),Parameters,ParValues,Infos,LocalWF), % relevant for test 1904
2350		not_with_enum_warning_and_possible_delay(
2351		(custom_explicit_sets:b_test_closure(CParameters,CParameterTypes,ClosureBody1,ParValues,negative,LocalWF),
2352		perfmessage_bexpr(forall,forall_counter_example(CParameters,ParValues),LHS)
2353		),LocalWF, WF, forall(CParameters), Infos).
2354
2355		:- use_module(library(timeout),[time_out/3]).
2356		not_with_enum_warning_and_possible_delay(C,WF,OuterWF,PP,Span) :-
2357		get_preference(disprover_mode,true),
2358		% in disprover mode we do not track WD errors, no need to start_attach_inner_abort_errors
2359		!,
2360		% delay potentially expensive quantifications in the hope of finding other contradictions earlier
2361		if( (time_out(not_with_enum_warning(C,WF,PP,Span),20,TRes),TRes \== time_out),
2362		copy_wfe_from_inner_if_necessary(WF,OuterWF),
2363		(get_wait_flag(2,not_with_enum_warning_and_possible_delay,OuterWF,LWF), % which priority to use ??
2364		debug_println(19,delay_not_in_disprover_mode),
2365		not_with_enum_warning_delay(C,LWF,WF,OuterWF,PP,Span))).
2366		not_with_enum_warning_and_possible_delay(C,WF,OuterWF,PP,Span) :-
2367		start_attach_inner_abort_errors(Level,not_with_enum_warning),
2368		call_cleanup(not_with_enum_warning(C,WF,PP,Span),
2369		re_attach_pending_inner_abort_errors(Level,OuterWF,_)),
2370		copy_wfe_from_inner_if_necessary(WF,OuterWF).
2371
2372
2373		:- block not_with_enum_warning_delay(?,-,?,?,?,?).
2374		not_with_enum_warning_delay(C,_,WF,OuterWF,PP,Span) :-
2375		debug_println(19,trigger_not_with_enum_warning_delay),
2376		not_with_enum_warning(C,no_wf_available,PP,Span),
2377		copy_wfe_from_inner_if_necessary(WF,OuterWF).
2378
2379		:- use_module(avl_tools,[quick_avl_approximate_size/2]).
2380		obvious_enumeration(LHS,[Id]) :- % TO DO : allow multiple ids
2381		% TO DO: unify with is_for_all_set_membership_predicate code below
2382		TLHSMembership = b(LHSMembership,_,_),
2383	?	member_conjunct(TLHSMembership,LHS,_),
2384		obvious_enum_aux(LHSMembership,Id).
2385
2386		obvious_enum_aux(member(TID,b(value(VAL),_,_)),ID) :- get_texpr_id(TID,ID),
2387		nonvar(VAL), VAL = avl_set(AVL), % TO DO: also support interval closures ?
2388		quick_avl_approximate_size(AVL,Size),
2389		Size<256.
2390		%obvious_enum_aux(equal(LHS,RHS),ID) :- % stillposes problem for test 231, investigate
2391		% ( get_texpr_id(LHS,ID) -> get_texpr_expr(RHS,value(_))
2392		% ; get_texpr_id(RHS,ID) -> get_texpr_expr(LHS,value(_))).
2393		% % TODO: do we need to accept integer(.),... literals?
2394
2395		% expands forall quantifier and thus enables that we also propagate from right to left
2396		% This helps for test 1397 (HandshakeSimple_TotFun)
2397		% TO DO: directly call the code which tries to expand a forall quantifier
2398		expand_forall_quantifier(Parameters,LHS,RHS,Infos,WF,ReificationVariable) :-
2399		(preferences:preference(use_smt_mode,true) -> true
2400		; preferences:preference(solver_strength,SS), SS>9), % sometimes contrapositive checking maybe not useful; see test 1368
2401		% TO DO: investigate and provide more principled heuristic
2402		b_interpreter_check:b_check_forall_wf(Parameters,LHS,RHS,Infos,[],[],WF,ReificationVariable).
2403
2404		% rewrite !(x,..).( TRUTH => (LHS2 => RHS2)) into !(x,...).(LHS2 => RHS2)
2405		peel_implications(Parameters,ParCard,LHS,RHS, NewLHS,NewRHS) :-
2406		%print(forall),nl, print(Parameters),nl,print(LHS),nl,
2407		% this patterns occurs often in Event-B translations to classical B
2408		LHS=b(truth,_,_),
2409		RHS=b(implication(LHS2,RHS2),_,_), % TO DO: maybe also accept nested forall and then add to Parameters?
2410		(is_inf_or_overflow_card(ParCard) -> true ; ParCard>50),
2411		% larger bound than below: maybe user explicitly wants to expand it
2412		!,
2413		peel_implications(Parameters,ParCard,LHS2,RHS2, NewLHS,NewRHS).
2414		peel_implications(_,_,LHS,RHS, LHS,RHS).
2415
2416		b_generate_for_all_list_domain_nolwf(Parameters,LHS,RHS,LS,S,ForAllDomain,NewRHS,WF) :-
2417	?	parameter_list_cardinality(Parameters,ParCard),
2418		peel_implications(Parameters,ParCard,LHS,RHS, LHS2,RHS2),
2419		b_generate_for_all_list_domain1(Parameters,ParCard,LHS2,RHS2,LS,S,OForAllDomain,NewRHS,WF),
2420		optlist_to_list(OForAllDomain,ForAllDomain). % resolve any optional_value/2 items
2421
2422		% generate the domain of a Universally Quantified Formula as a list
2423		b_generate_for_all_list_domain1(Parameters,_ParCard,LHS,RHS,LS,S,ForAllDomain,NewRHS,WF) :-
2424		% optimized treatment for formulas of the form !x.(x:S => RHS) or !(x,y).(x|->y:S => RHS)
2425		% to do: expand to more formulas, such as !(x,y).(x:S & y:T => RHS)
2426		% or !(x,y,z).( (x|->y:S & y|->z:S) => RHS)
2427		% 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))
2428		% or we could try and reify set membership for small domains and trigger implication
2429		is_for_all_set_membership_predicate(LHS,Parameters,Set,Pattern,ParameterValues),!,
2430		perfmessages_bexpr_call(good(forall),['Detected forall set membership over ',Ps,': '],
2431		LHS,bsyntaxtree:def_get_texpr_ids(Parameters,Ps)),
2432		NewRHS=RHS,
2433		b_generate_set_for_all_domain(Set,LS,S,Pattern,ParameterValues,ForAllDomain,WF).
2434		b_generate_for_all_list_domain1(Parameters,ParCard,LHS,RHS,LS,S,ForAllDomain,NewRHS,WF) :-
2435		b_generate_forall_closure(Parameters,LHS,LS,S,Closure,WF), % POSSIBLY NO NEED TO COMPILE
2436		b_generate_for_all_domain2(Closure,Parameters,ParCard,LHS,RHS,ForAllDomain,NewRHS,WF).
2437
2438		b_generate_for_all_domain2(Closure,_Parameters,_,LHS,RHS,ForAllDomain,NewRHS,WF) :-
2439		(LHS=b(truth,pred,_) ; ground_value(Closure)),
2440		!, NewRHS=RHS, % nl,print('FORALL EXPAND: '),(ground_value(Closure) -> print(ground(_Parameters)),nl, print_bexpr(LHS),nl ; print('NONGROUND!!'),nl,print_bexpr(RHS),nl), %%
2441		b_expand_closure_forall_to_list(Closure,ForAllDomain,WF).
2442		b_generate_for_all_domain2(_,Parameters,_,LHS,RHS,ForAllDomain,NewRHS,WF) :-
2443		is_a_conjunct(LHS,_,_), % otherwise we have already checked for set_membership above !
2444		LHS_Membership = b(member(_,_),_,_), % TO DO: also allow conjuncts
2445	?	member_conjunct(LHS_Membership,LHS,RestLHS),
2446		% !(x). ( x:Set & RestLHS => RHS) ---> !(x).(x:Set => (RestLHS => RHS))
2447		is_for_all_set_membership_predicate(LHS_Membership,Parameters,Set,Pattern,ParameterValues),
2448	?	max_cardinality_ok_for_expansion(Set,100,[],[]), % TO DO: simplify LS,S argument <----
2449		!,
2450		% as we expand Set without constraining RHS predicate, check if this is ok
2451		% indeed maximum cardinality of Set could be infinite !! !x.(x:NATURAL1 & x<N => P)
2452		% print('Splitting for all conjunct: '), print(Parameters),nl, print_bexpr(LHS_Membership),nl,print_bexpr(RestLHS),nl, %%
2453		perfmessage_bexpr(good(forall),'Splitting LHS of forall: ',LHS),
2454		NewRHS = b(implication(RestLHS,RHS),pred,[]), % TO DO: extract & join info
2455		b_generate_set_for_all_domain(Set,[],[],Pattern,ParameterValues,ForAllDomain,WF).
2456		b_generate_for_all_domain2(Closure,_Parameters,ParCard,LHS,RHS,ForAllDomain,NewRHS,WF) :-
2457		(is_inf_or_overflow_card(ParCard) -> true ; ParCard>8),
2458		!,
2459		NewRHS=RHS,
2460		perfmessage_bexpr(forall,'No optimisations applicable to forall (will delay until all variables are bound): ',LHS),
2461		% maybe we should generate this message only if ForAllDomain is var ?
2462		b_expand_closure_forall_to_list(Closure,ForAllDomain,WF).
2463		b_generate_for_all_domain2(_Closure,Parameters,ParCard,LHS,RHS,ForAllDomain,NewRHS,WF) :-
2464		NewLHS=b(truth,pred,[]), NewRHS=b(implication(LHS,RHS),pred,[]),
2465		b_generate_forall_closure(Parameters,NewLHS,[],[],Closure,WF),
2466		perfmessages_bexpr(good(forall),['Expanding forall with finite parameter type, card = ',ParCard,': '],LHS),
2467		b_expand_closure_forall_to_list(Closure,ForAllDomain,WF).
2468
2469		% code to decide whether a for all should be expanded if the
2470		% predicate contains a set membership predicate : !x.( (P & x:S & P') => Q)
2471		max_cardinality_ok_for_expansion(b(Expr,Type,_Info),Limit,LS,S) :- % which value to choose for Limit ??
2472	?	kernel_objects:max_cardinality(Type,TypeCard),
2473		( (number(TypeCard),TypeCard =< Limit) -> true ;
2474		max_cardinality_ok_for_expansion2(Expr,Limit,TypeCard,LS,S)).
2475
2476		max_cardinality_ok_for_expansion1(b(E,_,_),Limit,TC,LS,S) :-
2477		max_cardinality_ok_for_expansion2(E,Limit,TC,LS,S).
2478
2479		:- use_module(custom_explicit_sets,[efficient_card_for_set/3]).
2480
2481		max_cardinality_ok_for_expansion2(set_extension(E),Limit,_TC,_,_) :- !, length(E,Len), Len =< Limit.
2482		max_cardinality_ok_for_expansion2(interval(Up,Low),Limit,_TC,LS,S) :- !,
2483		get_integer(UpI,Up,LS,S), get_integer(LowI,Low,LS,S),
2484		UpI-LowI<Limit.
2485		max_cardinality_ok_for_expansion2(integer_set(GS),Limit,_TC,_LS,_S) :- !, b_global_set_cardinality(GS,Card),
2486		number(Card), Card =< Limit.
2487		max_cardinality_ok_for_expansion2(set_subtraction(A,_),Limit,TC,LS,S) :- !,
2488		max_cardinality_ok_for_expansion1(A,Limit,TC,LS,S).
2489		max_cardinality_ok_for_expansion2(image(RelA,_),Limit,TC,LS,S) :- !,
2490		max_cardinality_ok_for_expansion1(RelA,Limit,TC,LS,S).
2491		max_cardinality_ok_for_expansion2(function(_RelA,_),_Limit,_TC,_LS,_S) :- !,
2492		fail. % TO DO: we should look at the size of the range elements
2493		% max_cardinality_ok_for_expansion1(_RelA,_Limit,_TC,_LS,_S).
2494		max_cardinality_ok_for_expansion2(intersection(A,B),Limit,TC,LS,S) :- !,
2495		(max_cardinality_ok_for_expansion1(A,Limit,TC,LS,S) -> true ; max_cardinality_ok_for_expansion1(B,Limit,TC,LS,S)).
2496		max_cardinality_ok_for_expansion2(union(A,B),Limit,TC,LS,S) :- !,
2497		max_cardinality_ok_for_expansion1(A,Limit,TC,LS,S), max_cardinality_ok_for_expansion1(B,Limit,TC,LS,S).
2498		max_cardinality_ok_for_expansion2(range(A),Limit,TC,LS,S) :- !,
2499		max_cardinality_ok_for_expansion1(A,Limit,TC,LS,S).
2500		max_cardinality_ok_for_expansion2(domain(A),Limit,TC,LS,S) :- !,
2501		max_cardinality_ok_for_expansion1(A,Limit,TC,LS,S).
2502		max_cardinality_ok_for_expansion2(domain_restriction(_A,B),Limit,TC,LS,S) :- !,
2503		max_cardinality_ok_for_expansion1(B,Limit,TC,LS,S). % note: finite A does not guarantee finite result
2504		max_cardinality_ok_for_expansion2(domain_subtraction(_A,B),Limit,TC,LS,S) :- !,
2505		max_cardinality_ok_for_expansion1(B,Limit,TC,LS,S).
2506		max_cardinality_ok_for_expansion2(range_restriction(A,_B),Limit,TC,LS,S) :- !,
2507		max_cardinality_ok_for_expansion1(A,Limit,TC,LS,S). % note: finite B does not guarantee finite result
2508		max_cardinality_ok_for_expansion2(range_subtraction(A,_B),Limit,TC,LS,S) :- !,
2509		max_cardinality_ok_for_expansion1(A,Limit,TC,LS,S).
2510		max_cardinality_ok_for_expansion2(direct_product(A,B),Limit,TC,LS,S) :- !,
2511		max_cardinality_ok_for_expansion2(cartesian_product(A,B),Limit,TC,LS,S).
2512		max_cardinality_ok_for_expansion2(parallel_product(A,B),Limit,TC,LS,S) :- !,
2513		max_cardinality_ok_for_expansion2(cartesian_product(A,B),Limit,TC,LS,S).
2514		max_cardinality_ok_for_expansion2(cartesian_product(A,B),Limit,TC,LS,S) :- !,
2515		ILimit is Limit//2, ILimit>0, %use sqrt ?
2516		max_cardinality_ok_for_expansion1(A,ILimit,TC,LS,S),
2517		max_cardinality_ok_for_expansion1(B,ILimit,TC,LS,S).
2518		max_cardinality_ok_for_expansion2(value(S),Limit,_TC,_LS,_S) :- !,
2519		get_max_card_for_value(S,MaxCard),
2520		MaxCard =< Limit.
2521		max_cardinality_ok_for_expansion2(identifier(_ID),_Limit,TC,_LS,_S) :- !, number(TC).
2522		% TO DO: check if ID is fully defined; if so use card else accept as it will
2523		% probably be represented by a list and the forall constraints could be useful in finding ID's value
2524		% 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?
2525		max_cardinality_ok_for_expansion2(external_function_call(_,_),_,_,_,_) :- !,fail.
2526		max_cardinality_ok_for_expansion2(lazy_lookup_expr(_),_,_,_,_) :- !,fail.
2527		max_cardinality_ok_for_expansion2(record_field(_,_),_Limit,_TC,_LS,_S) :- !, fail.
2528		max_cardinality_ok_for_expansion2(E,Limit,TC,_LS,_S) :- functor(E,F,N),
2529		print(unknown_max_card(F/N,Limit,TC)),nl,fail.
2530
2531
2532		:- use_module(kernel_cardinality_attr,[clpfd_card_domain_for_var/3]).
2533
2534		get_max_card_for_value(S,MaxCard) :- var(S), !,
2535		clpfd_card_domain_for_var(S,_,Max),
2536		number(Max),
2537		MaxCard=Max.
2538		get_max_card_for_value([],R) :- !, R=0.
2539		get_max_card_for_value([_|T],R) :- !,get_max_card_for_value(T,TMax), R is TMax+1.
2540		get_max_card_for_value(S,Card) :- efficient_card_for_set(S,Card,C),!,
2541		call(C), number(Card).
2542
2543
2544		get_integer(X, b(Expr,integer,_),LS,S) :- get_integer2(Expr,X,LS,S).
2545		get_integer2(integer(X),X,_,_) :- number(X).
2546		get_integer2(identifier(Id),Val,LS,S) :- lookup_value(Id,LS,S,int(Val)), number(Val).
2547
2548		member_conjunct(Predicate,Conjunction,Rest) :-
2549		conjunction_to_list(Conjunction,List),
2550	?	select(Predicate,List,RestList),
2551		conjunct_predicates(RestList,Rest).
2552		% member_conjunct(Conj,Conj,b(truth,pred,[])). covered by case above
2553
2554		b_generate_set_for_all_domain(Set,LS,S,Pattern,ParameterValues,ForAllDomain,WF) :-
2555		b_compute_expression(Set,LS,S,EvSet,WF),
2556		expand_custom_set_to_list_wf(EvSet,ESet,_Done,b_generate_set_for_all_domain,WF),
2557		filter_and_convert_list_to_parameter_tuples(ESet,Pattern,ParameterValues,ForAllDomain).
2558
2559
2560		% check if it is a predicate of the form x:S or x:Sx & y:Sy ... which we can optimize
2561		% (i.e. compute SET before all values inside it are fully known)
2562		is_for_all_set_membership_predicate(LHS,Parameters,Set,Pattern,ParameterValues) :-
2563		% print('CHECK FORALL : '), translate:print_bexpr(LHS),nl,nl,
2564		get_texpr_ids(Parameters,ParIDs), % TO DO: call get_texpr_ids before
2565		same_length(ParIDs,ParameterValues),
2566		is_for_all_set_membership_predicate2(LHS,ParIDs,ParIDs,UnmatchedParIDs,Set,Pattern,ParameterValues,_UPV),
2567		UnmatchedParIDs=[].
2568
2569		% TODO: maybe also deal with existential quantifiers #x.(x|->y:Set) -> in Pattern x becomes free var
2570		is_for_all_set_membership_predicate2(LHS,All,ParIDs,UnmatchedParIDs,Set,Pattern,ParameterValues,UPV) :-
2571		is_member_test(LHS,Element,Set),
2572		!,
2573		identifiers_not_used_in_bexp(All,Set),
2574		convert_to_prolog_pattern_match(Element,ParIDs,UnmatchedParIDs,Pattern,ParameterValues,UPV).
2575		% TO DO: also allow failing pattern matches ?!; at least when splitting
2576		is_for_all_set_membership_predicate2(LHS,All,ParIDs,ParIDs2,Set,
2577		(Pat1,Pat2),ParameterValues,UPV) :-
2578		is_a_conjunct(LHS,LHS1,LHS2), % we could have something of the form x:Sx & y:Sy ...
2579		Set = b(cartesian_product(Set1,Set2),couple(T1,T2),[]),
2580		is_for_all_set_membership_predicate2(LHS1,All,ParIDs, ParIDs1,Set1,Pat1,ParameterValues,PV1),
2581		get_texpr_type(Set1,T1),
2582		!,
2583		is_for_all_set_membership_predicate2(LHS2,All,ParIDs1,ParIDs2,Set2,Pat2,PV1,UPV),
2584		get_texpr_type(Set2,T2).
2585
2586		% TO DO: maybe use a more general test to be reused in other places
2587		is_member_test(b(P,_,_),Element,Set) :- is_member_test_aux(P,Element,Set).
2588		is_member_test_aux(member(Element,Set),Element,Set).
2589		% also detect equalities: important for tests 28,29 after b_compiler can introduce equalities for singleton set memberships
2590		is_member_test_aux(equal(Element,SetVal),Element,Set) :- % TO DO : also other direction + other kinds of values ?
2591		SetVal = b(value(SV),T,I),
2592		Set = b(value([SV]),set(T),I).
2593
2594		identifiers_not_used_in_bexp(IDList,Expr) :-
2595		find_identifier_uses(Expr,[],Used),
2596		id_check(IDList,Used).
2597		id_check([],_).
2598		id_check([ID|T],Used) :-
2599		nonmember(ID,Used), !,
2600		id_check(T,Used).
2601
2602		% check if an expression can be converted to a Prolog linear unification/pattern match
2603		% give an list of free identifiers IDS
2604		convert_to_prolog_pattern_match(b(E,_,_),IDS,OutIDS,Pattern,VarsIn,VarsOut) :-
2605		convert_to_prolog_pattern_match2(E,IDS,OutIDS,Pattern,VarsIn,VarsOut).
2606
2607		convert_to_prolog_pattern_match2(identifier(ID),IDsIn,IDsOut,PatVariable,VarsIn,VarsOut) :-
2608		% check that the identifier is in the list of quantified variables and thus unbound
2609		!,
2610	?	(nth1(Nr,IDsIn,ID,IDsOut)
2611		-> nth1(Nr,VarsIn,PatVariable,VarsOut) % put fresh PatVariable in the Pattern
2612		),!.
2613		convert_to_prolog_pattern_match2(couple(ID1,ID2),IDS,OutIDS,Pattern,VarsIn,VarsOut) :-
2614		Pattern = (Pat1,Pat2),
2615		convert_to_prolog_pattern_match(ID1,IDS,RemIDS,Pat1,VarsIn,VarsInt),
2616		convert_to_prolog_pattern_match(ID2,RemIDS,OutIDS,Pat2,VarsInt,VarsOut).
2617		convert_to_prolog_pattern_match2(value(V),IDsIn,IDsOut,Pattern,VarsIn,VarsOut) :-
2618		can_be_used_for_unification(V), % check if we can use Prolog unification for equality
2619		!, Pattern=V, IDsOut=IDsIn, VarsIn=VarsOut.
2620		% TO DO: records?
2621
2622		% a pattern match code to be used with above; ensure we do not instantiate values
2623		pattern_match(PatVar,Val,Res) :- var(PatVar),!,PatVar=Val, Res=pred_true. % we have a free pattern variable
2624		pattern_match((Pat1,Pat2),(V1,V2),Res) :- !,
2625		pattern_match(Pat1,V1,R1), conjoin_simple(R1,R2,Res),
2626		pattern_match(Pat2,V2,R2).
2627		pattern_match(GroundPatVal,Val,Res) :- % we have a value that can_be_used_for_unification
2628		when( ?=(GroundPatVal,Val), (GroundPatVal=Val -> Res=pred_true ; Res=pred_false)).
2629
2630		:- block conjoin_simple(-,?,?). % TO DO: also allow second arg to unblock
2631		conjoin_simple(pred_true,X,X).
2632		conjoin_simple(pred_false,_,pred_false).
2633
2634		% similar to get_template(V,T,[])
2635		% but more restricted; we only accept those values where equality corresponds to Prolog unification
2636		% get_template is different and can assume normalized values, e.g., for empty set
2637		% pairs are treated above in convert_to_prolog_pattern_match2
2638		can_be_used_for_unification(V) :- var(V),!,fail.
2639		can_be_used_for_unification(int(V)) :- integer(V).
2640		can_be_used_for_unification(string(S)) :- ground(S).
2641		can_be_used_for_unification(fd(S,T)) :- ground(S), ground(T).
2642		can_be_used_for_unification(pred_false).
2643		can_be_used_for_unification(pred_true).
2644		can_be_used_for_unification(term(floating(F))) :- number(F).
2645		% TODO: simple atomic freevalues?
2646
2647
2648		% take a list and a pattern and filter the values that do not match the Pattern
2649		% Unification with the Pattern also instantiates the ParameterValues
2650		% used for triggering and instantiating right-hand-side of forall: !x.(x:Set => RHS)
2651		% TODO: Instead of converting to a Prolog Unification we could use kernel_equality instead of pattern_match
2652		% but this is not obvious, as the pattern contains free variables and equality would never return true
2653		% we would need to apply kernel_equality only to the ground pattern parts
2654		:- block filter_and_convert_list_to_parameter_tuples(-,?,?,?).
2655		filter_and_convert_list_to_parameter_tuples([],_,_,[]).
2656		filter_and_convert_list_to_parameter_tuples([H|T],Pattern,ParameterValues,Res) :-
2657		copy_term((Pattern,ParameterValues),(CPat,CPV)),
2658		pattern_match(CPat,H,PredRes), % check if pattern matches new element H in set; careful not to instantiate H
2659	?	filter_and_convert_list_to_parameter_tuples_aux(PredRes,CPV,T,Pattern,ParameterValues,Res).
2660
2661		:- block filter_and_convert_list_to_parameter_tuples_aux(-,?,-,?,?,?).
2662		filter_and_convert_list_to_parameter_tuples_aux(PredRes,CPV,T,Pattern,ParameterValues,Res) :-
2663		var(PredRes),!, % we cannot decide yet whether the optional value is to be used or not
2664		Res = [optional_value(CPV,PredRes)|RT], % create constructor for map_optlist or similar
2665		filter_and_convert_list_to_parameter_tuples(T,Pattern,ParameterValues,RT).
2666		filter_and_convert_list_to_parameter_tuples_aux(PredRes,CPV,T,Pattern,ParameterValues,Res) :-
2667		(PredRes = pred_true % we have a match, universal quantifier applies to H
2668		-> Res = [CPV|RT]
2669		; % element of set does not match pattern; universal quantifier does not apply
2670		% ProB used to only accept non-failing pattern matches;
2671		% now we also accept tuples with static parts where Prolog unification can fail
2672		Res=RT
2673		),
2674	?	filter_and_convert_list_to_parameter_tuples(T,Pattern,ParameterValues,RT).
2675
2676		:- use_module(tools,[map_optlist/2,optlist_to_list/2]).
2677		:- use_module(library(lists),[maplist/3]).
2678		expand_forall1(OList,RHS,Parameters,WF) :-
2679		ground_bexpr(RHS), % because compiled this means we cannot do any constraint propagation on variables in RHS
2680		optlist_to_list(OList,List),
2681		ground_value(List), % ditto here: no variables on which we could do constraint propagation
2682		%% preferences:get_preference(double_evaluation_when_analysing,false), % causes test 1112 to fail TO DO:fix
2683		% otherwise we do not have a real redundancy wrt to not exists check
2684		debug_println(15,ground_forall_translating_into_not_exists(Parameters)),
2685		!,
2686		init_quantifier_wait_flag(WF,forall,Parameters,ParResult,unknown,LocalWF),
2687		% Advantage over treatment below: NegRHS is interpreted only once
2688		% but we cannot provide any instantiations and there must not be any links with variables outside of the forall !!
2689		create_negation(RHS,NegRHS),
2690		not_with_enum_warning( (
2691		b_interpreter:test_forall_instance(NegRHS,Parameters,LocalWF,negative,ParResult),
2692		% test_forall_instance can fail; if inconsistency detected in WF0
2693		kernel_waitflags:ground_det_wait_flag(LocalWF),
2694		member(ParResultInList,List), % check the body for every solution
2695		lists:maplist(kernel_objects:equal_object,ParResultInList,ParResult), % match params with solutions of domain
2696		kernel_waitflags:ground_wait_flags(LocalWF)
2697		), LocalWF, forall(Parameters), RHS
2698		).
2699		expand_forall1(List,RHS,Parameters,WF) :-
2700		% blocking version of maplist which also filters out some optional_value/2 terms:
2701	?	map_optlist(b_interpreter:test_forall_instance(RHS,Parameters,WF,positive),List).
2702
2703		% test RHS of a forall for a particular valuation ParResult of the Parameters
2704		test_forall_instance(RHS,Parameters,WF,NegationContext,ParResult) :-
2705		LocalState=[],State=[],
2706	?	if(set_up_typed_localstate(Parameters,ParResult,_TypedVals,LocalState,NewLocalState,NegationContext),
2707		true,
2708		(nl,print(set_up_typed_localstate_failed(Parameters,ParResult,_,LocalState,NewLocalState)),nl,
2709		% it can happen that ParResult has constraints on it and that setting up the typing info detects the error
2710		% add_internal_error('Call failed: ', set_up_typed_localstate(Parameters,ParResult,_,LocalState,NewLocalState)),
2711		fail)),
2712	?	b_optimized_b_test_instance(RHS,NewLocalState,State,WF).
2713
2714		reification_relevant_for_op(implication(_,_)).
2715		reification_relevant_for_op(equivalence(_,_)).
2716		reification_relevant_for_op(disjunct(_,_)).
2717		% TODO: maybe check if a conjunct contains implication
2718		% relevant for example for: n=2000 & f:1..n-->BOOL & !i.(i:2..n => (f(i)=TRUE =>f(i-1)=FALSE)) & f(1)=TRUE
2719
2720		b_optimized_b_test_instance(RHS,NewLocalState,State,WF) :-
2721		get_texpr_expr(RHS,RE), reification_relevant_for_op(RE), % we will attempt reification
2722		attempt_reification,
2723		\+ always_well_defined(RHS), % this will prevent reification
2724		!,
2725		% try and compile in the hope that now the WD issue disappears:
2726		b_compiler:b_optimize(RHS,[],NewLocalState,State,NewRHS,WF),
2727		b_test_boolean_expression(NewRHS,NewLocalState,State,WF).
2728		b_optimized_b_test_instance(RHS,NewLocalState,State,WF) :-
2729	?	b_test_boolean_expression(RHS,NewLocalState,State,WF).
2730		% using b_test_inner_boolean_expression considerably slows down NQueens, Sudoku,...
2731		% WF=InnerWF. /* give the boolean expression a chance to do ground propagations first */
2732
2733
2734		% use this when the test boolean expression could be called with WF0 already set
2735		% give the inner expression a chance to do the deterministic stuff first
2736		b_test_inner_boolean_expression(Pred,LocalState,State,WF) :-
2737		kernel_waitflags:clone_wait_flags_from1(WF,GroundUponFinish,WF2),
2738		% set WF0 to variable to propagate deterministic infos first:
2739	?	b_test_boolean_expression(Pred,LocalState,State,WF2),
2740	?	kernel_waitflags:clone_wait_flags_from1_finish(WF,GroundUponFinish,WF2).
2741		% the same for testing negation of a predicate:
2742		b_not_test_inner_boolean_expression(Pred,LocalState,State,WF) :-
2743		kernel_waitflags:clone_wait_flags_from1(WF,GroundUponFinish,WF2),
2744		% set WF0 to variable to propagate deterministic infos first:
2745	?	b_not_test_boolean_expression(Pred,LocalState,State,WF2),
2746	?	kernel_waitflags:clone_wait_flags_from1_finish(WF,GroundUponFinish,WF2).
2747
2748		/* now the same as above; but without converting list of values into pairs */
2749		:- assert_pre(b_interpreter:b_expand_closure_forall_to_list(Closure,_Result,_WF),
2750		(nonvar(Closure), custom_explicit_sets:is_closure(Closure,_Parameters,_ParameterTypes,ClosureBody),
2751		nonvar(ClosureBody),
2752		bsyntaxtree:check_if_typed_predicate(ClosureBody))).
2753		:- assert_post(b_interpreter:b_expand_closure_forall_to_list(_Closure,Result,_WF),
2754		b_interpreter:value_type(Result)).
2755		b_expand_closure_forall_to_list(Closure,Result,WF) :- nonvar(Closure),
2756		Closure = closure(Parameters,ParameterTypes,ClosureBody),
2757		!,
2758		% print('Expand closure forall: '), translate:print_bexpr(ClosureBody),nl,
2759		% at the moment we may wait too long before expanding this closure
2760		% 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 ?
2761		(performance_monitoring_on,
2762		term_variables(ClosureBody,Vars),
2763		Vars \= []
2764		->
2765		perfmessagecall(delaying_forall(Parameters,vars(Vars),out(ParValues)),
2766		translate:print_bexpr(ClosureBody),ClosureBody)
2767		; true),
2768		ground_bexpr_check(ClosureBody,BodyGround),
2769		add_texpr_infos(ClosureBody,[quantifier_kind(forall)],ClosureBody1), % for call_stack
2770		delay_setof_list_wf( ParValues,
2771		%% (print_bt_message(expanding_forall_closure(Parameters,ClosureBody,ParValues)), %%
2772		custom_explicit_sets:b_test_closure(Parameters,ParameterTypes,ClosureBody1,
2773		ParValues,all_solutions,WF)
2774		%% ,print_bt_message(expanded(Parameters,ParValues)) ) %%
2775		,
2776		Result,
2777		BodyGround,WF).
2778		b_expand_closure_forall_to_list(Closure,Result,WF) :-
2779		add_internal_error('Illegal Call: ', b_expand_closure_forall_to_list(Closure,Result,WF)),
2780		fail.
2781
2782
2783		:- assert_pre(b_interpreter:set_up_typed_localstate(V,S,_), (list_skeleton(V),list_skeleton(S))).
2784		:- assert_post(b_interpreter:set_up_typed_localstate(_,_,R),list_skeleton(R)).
2785
2786		set_up_typed_localstate(Identifiers,InState,OutState) :-
2787	?	set_up_typed_localstate(Identifiers,_FreshVars,_TypedVals,InState,OutState,positive).
2788
2789		:- use_module(b_enumerate,[construct_typedval_infos/4]).
2790		set_up_typed_localstate([],[],[],State,State,_).
2791		set_up_typed_localstate([Identifier|IdRest],[Val|ValRest],[typedval(Val,Type,Var,TINFO)|TRest],
2792		% TO DO: add info field to typedval: source_span, and lambda_result/do_not_enumerate infos
2793		InState,OutState,NegationContext) :-
2794		% The other way round (first add Identfier, then IdRest) would be more efficient,
2795		% but we do it this way to keep compatibility with a previous version.
2796		% In specfile:compute_operation_effect, the arguments of an operation are in the same order than in the store
2797	?	set_up_typed_localstate(IdRest,ValRest,TRest,InState,InterState,NegationContext),
2798		def_get_texpr_id(Identifier,Var), get_texpr_type(Identifier,Type),
2799		get_texpr_info(Identifier,Info),
2800		triggers_enum_warning(Var,Type,Info,NegationContext,TriggersEnumWarning),
2801		get_texpr_info(Identifier,Infos),construct_typedval_infos(Var,Infos,TriggersEnumWarning,TINFO),
2802	?	add_typed_var_to_localstate(Var,Val,Type,InterState,OutState).
2803
2804		% same version; but with list of atomic ids and list of types
2805		set_up_typed_localstate2([],[],_,[],[],State,State,_).
2806		set_up_typed_localstate2([Var|IdRest],[Type|TyRest],Infos,[Val|ValRest],[typedval(Val,Type,Var,TINFO)|TRest],
2807		InState,OutState,NegationContext) :-
2808		% The other way round (first add Identfier, then IdRest) would be more efficient,
2809		% but we do it this way to keep compatibility with a previous version.
2810		% In specfile:compute_operation_effect, the arguments of an operation are in the same order than in the store
2811	?	set_up_typed_localstate2(IdRest,TyRest,Infos,ValRest,TRest,InState,InterState,NegationContext),
2812		triggers_enum_warning(Var,Type,Infos,NegationContext,TriggersEnumWarning),
2813		construct_typedval_infos(Var,Infos,TriggersEnumWarning,TINFO),
2814	?	add_typed_var_to_localstate(Var,Val,Type,InterState,OutState).
2815
2816		% possible values for NegationContext: positive, negative, all_solutions
2817		triggers_enum_warning(Id,Type,Info,all_solutions,Res) :- !,
2818		Res = trigger_throw(b(identifier(Id),Type,Info)).
2819		%triggers_enum_warning(Id,_Type,Info,NegationContext,trigger_false(Id)) :- % no longer used
2820		% NegationContext=positive, % when negated then success will occur if all possibilities have been tried out
2821		% memberchk(introduced_by(exists),Info),
2822		% %%((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),
2823		% %% The Disprover now checks whether unfixed_deferred sets were involved; keeping track of implicit enumerations of %deferred sets is just too difficult
2824		% !.
2825		triggers_enum_warning(Id,Type,Info,_,trigger_true(b(identifier(Id),Type,Info))).
2826
2827
2828		add_typed_var_to_localstate(Var,Val,Type,InState,OutState) :-
2829		add_var_to_localstate(Var,Val,InState,OutState),
2830		%%when(ground(Val), (print(' ++ '),print(Var),print(' ---> '), print(Val),nl)),
2831	?	kernel_objects:basic_type(Val,Type). %% ,print(ok(Val)),nl.
2832
2833		/*
2834		xxb_test_exists(Parameters,Condition,Infos,LocalState,State,WF) :-
2835		b_check_boolean_expression(b(exists(Parameters,Condition),pred,Infos),LocalState,State,WF,NR),
2836		get_exists_used_ids(Parameters,Condition,Infos,Used),lookup_values_if_vars(Used,LocalState,State,WaitVars),
2837		\+ ground(WaitVars),
2838		!,
2839		debug_println(9,unfolding_exists(Parameters)), print(unfolding(Parameters)),nl,
2840		%translate:print_bexpr(Condition),nl, print(State),nl, print(LocalState),nl,nl,
2841		NR=pred_true. %, print(set_res(pred_true)),nl.
2842		% 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
2843		*/
2844
2845		b_test_exists(Parameters,Condition,Infos,LocalState,State,WF) :-
2846		get_wait_flag0(WF,WF0),
2847	?	b_test_exists(WF0,Parameters,Condition,Infos,LocalState,State,WF).
2848
2849		:- block b_test_exists(-,?,?, ?,?,?,?).
2850		b_test_exists(_LWF,Parameters,Condition,Infos,LocalState,State,WF) :-
2851		if((attempt_reification, % what if there is a wd_condition attached to Condition?
2852		b_interpreter_check:b_check_exists_wf(Parameters,Condition,Infos,LocalState,State,WF,ReificationVariable)),
2853		% try and expand quantifiers of small cardinality; see also expand_forall_quantifier
2854		% tested in test 1452
2855		(debug_println(9,expanded_exists(Parameters)),
2856		ReificationVariable=pred_true),
2857	?	b_test_exists_wo_expansion(Parameters,Condition,Infos,LocalState,State,WF)).
2858
2859		%attempt_reification :- preferences:preference(use_clpfd_solver,true),!. % all tests seem to pass
2860		attempt_reification :- preferences:preference(use_smt_mode,true),!.
2861		attempt_reification :- preferences:preference(solver_strength,SS), SS>9.
2862		% TO DO: maybe take context into account: setup constants, becomes such, ... allow_skipping_over_components/reset_component_info(true)
2863
2864		:- use_module(kernel_tools,[bexpr_variables/2, value_variables/3]).
2865
2866		% we treat the existential quantifier without expansion into a disjuncition aka reification
2867		b_test_exists_wo_expansion(Parameters,Condition,Infos,LocalState,State,WF) :-
2868		%print(test_exists(Parameters,Infos)),nl,portray_waitflags(WF),nl,
2869	?	(preference(lift_existential_quantifiers,true) ; member(allow_to_lift_exists,Infos)),
2870		!, % we enumerate the exists normally; treat it just like an ordinary predicate
2871		% lifting may generate multiple solutions; but avoids delaying enumeration of quantified parameters
2872		% print('*Lifting existential quantifier: '), translate:print_bexpr(Condition),nl,
2873	?	set_up_typed_localstate(Parameters,ParaValues,TypedVals,LocalState,NewLocalState,positive),
2874		copy_wf_start(WF,b_test_exists_wo_expansion,CWF),
2875		opt_push_wait_flag_call_stack_quantifier_info(CWF,exists,Parameters,ParaValues,Infos,CWF2),
2876	?	b_test_boolean_expression(Condition,NewLocalState,State,CWF2),
2877		% often we do not need to enumerate TypedVals; they can be derived, but we could have #y.(y>x) and need to enum y
2878		b_tighter_enumerate_values_in_ctxt(TypedVals,Condition,CWF2),
2879	?	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)
2880		b_test_exists_wo_expansion(Parameters,Condition,Infos,LocalState,State,WF) :-
2881		get_exists_used_ids(Parameters,Condition,Infos,Used),
2882		% IT IS IMPORTANT THAT THE USED INFO IS CORRECT ; otherwise the WaitVars will be incorrect
2883		% The used_ids info does not include the Parameters of the existential quantifier !
2884	?	set_up_typed_localstate(Parameters,ParaValues,TypedVals,LocalState,NewLocalState,positive),
2885		lookup_values_if_vars(Used,LocalState,State,WaitVarsState), % TO DO: we could use b_compiler instead
2886		% What if the Condition was compiled and now contains a previously used_variable inside a closure/value ?
2887		%term_variables((Condition,WaitVarsState),WaitVars), % this can be expensive when we have large data values (see rule_RVF219/rule_RVF219_compo.mch)
2888		bexpr_variables(Condition,CondVars),
2889		value_variables(WaitVarsState,CondVars,WaitVars),
2890		% now determine which WaitVars are really worth waiting for, e.g., do not wait for res in #x.(x:E & ... res=min(f(x)))
2891		% relevant tests: 1868, 1194, 383, 1642, 1708, 1003, 1080, 1081, 1943
2892		(remove_ids_defined_by_equality(WaitVars,LocalState,State,Infos,RealWaitVars) -> RemovedVars=true
2893		; RealWaitVars = WaitVars, RemovedVars=false),
2894		opt_push_wait_flag_call_stack_quantifier_info(WF,exists,Parameters,ParaValues,Infos,WF2),
2895		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
2896	?	b_test_boolean_expression(Condition,NewLocalState,State,LocalWF), /* check Condition */
2897	?	ground_det_wait_flag(LocalWF), % print('det no contradiction'),nl,flush_output,
2898		b_tighter_enumerate_values_in_ctxt(TypedVals,Condition,LocalWF), % will not yet enumerate
2899		(% we could treat allow_to_lift_exists also here by setting ESWF=1; but 1162 then fails
2900		get_preference(data_validation_mode,true),
2901		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
2902		-> get_wait_flag(50000,b_test_exists(Parameters),WF,ESWF) % 100000 sufficient for test 1945; 869 for rule_CHAMPS in private_examples/ClearSy/2023
2903		; 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
2904		when((nonvar(ESWF);ground(RealWaitVars)),b_enumerate_exists(ESWF,RemovedVars,WaitVars,Parameters,Infos,LocalWF,WF)).
2905
2906
2907		:- use_module(tools,[remove_variables/3]).
2908		:- use_module(kernel_tools,[value_variables/2]).
2909		% if we have #x.( P & y = E(x)) we do not have to wait for y to be known
2910		remove_ids_defined_by_equality(WaitVars,LocalState,State,Infos,RealWaitVars) :- WaitVars \== [],
2911		memberchk(used_ids_defined_by_equality(Ideq),Infos),
2912		Ideq = [ID1|_], % currently we only look at one used_id defined by equality,
2913		% we could have #x.(P & y=E(z) & z=E(y)): TODO: improve computation in ast_cleanup
2914		(memberchk(bind(ID1,VAL),LocalState) -> true ; memberchk(bind(ID1,VAL),State)),
2915		value_variables(VAL,VARS),
2916		remove_variables(WaitVars,VARS,RealWaitVars),
2917		debug_println(9,removed_ids_def_by_equality(WaitVars,ID1,RealWaitVars)).
2918
2919
2920		b_enumerate_exists(ESWF,RemovedVars,WaitVars,Parameters,Infos,LocalWF,WF) :-
2921		%print(enum_exists(ESWF,RemovedVars,WaitVars,Parameters,LocalWF,WF)),nl,
2922		((RemovedVars=false,var(ESWF) ; % WaitVars guaranteed to be ground
2923		ground(WaitVars)) % TODO: replace this by an optimised version of ground check
2924		-> get_idle_flag(Parameters,WF,LWF),
2925		/* allow all other co-routines waiting on WaitVars to complete */
2926		/* Note however: if WF grounding as triggered two non-deterministic co-routines this
2927		will allow the other non-determinism to run first, duplicating the number of calls !
2928		This has been fixed by storing seperate waitflag variables for same prio in kernel_waitflags
2929		TODO: However, for enumeration of FD variables this might still happen and lead to duplication of
2930		calls to b_enumerate_exists_aux_ground
2931		*/
2932		%print(get_idle(Parameters,WaitVars)),nl, %kernel_waitflags:portray_waitflags(WF),nl,nl,
2933		b_enumerate_exists_aux_ground(LWF,WaitVars,Parameters,Infos,LocalWF,WF)
2934		; debug_println(9,semi_lifting_exists(ESWF,Parameters)),
2935		% add_message_wf(exists,'Semi-lifting exists:',Parameters,Parameters,WF),portray_waitflags(LocalWF),nl,
2936		kernel_waitflags:copy_waitflag_store(LocalWF,WF) % outer WF will now drive enumeration
2937		% Note: in case a LET has been moved inside and replaced this may lead to duplication
2938		).
2939
2940		:- if(environ(prob_safe_mode,true)).
2941		get_idle_flag(Parameters,WF,LWF) :- kernel_waitflags:get_idle_wait_flag(b_enumerate_exists(Parameters),WF,LWF),
2942		(var(LWF) -> true ; add_internal_error('Illegal idle waitflag for exists:',get_idle_flag(Parameters,WF,LWF))).
2943		:- else.
2944		get_idle_flag(Parameters,WF,LWF) :- kernel_waitflags:get_idle_wait_flag(b_enumerate_exists(Parameters),WF,LWF).
2945		:- endif.
2946
2947		:- block b_enumerate_exists_aux_ground(-,?,?,?,?,?).
2948		b_enumerate_exists_aux_ground(_,_WaitVars,Parameters,Infos,LocalWF,_WF) :-
2949		/* Note: this does a local cut: so it is important
2950		that all conditions are fully evaluated before performing the cut ; otherwise
2951		solutions will be lost */
2952		% print_bt_message('ENUMERATE EXISTS'(_Parameters)),nl, % portray_waitflags(_WF),
2953		if(ground_wait_flags_for_exists(Parameters,LocalWF),true,
2954		(perfmessage(exists,'Late bound exists failed: ',Parameters,Infos),fail)).
2955
2956
2957		ground_wait_flags_for_exists(Parameters,LocalWF) :-
2958		\+ enumeration_warning_occured_in_error_scope,
2959		get_current_error_scope(Level),
2960	?	\+ error_manager:throw_error(Level,_,_),
2961		!, % current scope is already clean, no need to enter a fresh one
2962		ground_wait_flags_for_exists2(Parameters,LocalWF,Level).
2963		ground_wait_flags_for_exists(Parameters,LocalWF) :-
2964		enter_new_clean_error_scope(Level,ground_wait_flags_for_exists),
2965		% Note: see {x|x:1..10 & #y.(y>x & y*y >10)} in test 2210:
2966		% we do not want to throw enum warnings even if the outer scope does in case a solution is found
2967		% 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
2968		call_cleanup(ground_wait_flags_for_exists2(Parameters,LocalWF,Level),
2969		exit_error_scope(Level,_,ground_wait_flags_for_exists)).
2970
2971		ground_wait_flags_for_exists2(_Parameters,LocalWF,Level) :-
2972	?	(ground_constraintprop_wait_flags(LocalWF)
2973		-> % local cut: one solution is sufficient.
2974		clear_enumeration_warning_in_error_scope(Level)
2975		% ; %print(fail),nl, % do not clear enumeration warnings fail
2976		).
2977
2978
2979		:- use_module(b_ast_cleanup,[check_used_ids_info/4]).
2980		get_exists_used_ids(Parameters,Condition,Infos,Used) :-
2981		preference(prob_safe_mode,true),!,
2982	?	(select(used_ids(Used),Infos,Rest)
2983		-> check_used_ids_info(Parameters,Condition,Used,exists), %% comment in to check used_ids field
2984		(member(used_ids(_),Rest)
2985		-> add_internal_error('Multiple used_ids info fields:',Parameters:Infos) ; true)
2986		;
2987		add_internal_error(
2988		'Expected information of used identifiers in exists information',Parameters:Infos),
2989		bsyntaxtree:find_identifier_uses(Condition, [], Used)
2990		).
2991		get_exists_used_ids(Parameters,Condition,Infos,Used) :-
2992	?	member(used_ids(Used),Infos) -> true
2993		;
2994		add_internal_error(
2995		'Expected information of used identifiers in exists information',Parameters:Infos),
2996		bsyntaxtree:find_identifier_uses(Condition, [], Used).
2997		% what if we call test_exists for a negated universal quantifier ??
2998
2999
3000
3001
3002		:- use_module(kernel_tools,[ground_state/1]).
3003		/* the following causes performance problems with examples/B/Mathematical/GraphIso/CheckGraphIsomorphism
3004		and with lausanne.mch in SMT mode */
3005		b_not_test_exists(Parameters,Condition,Infos,LocalState,State,_,WF) :-
3006		is_a_conjunct(Condition,LHS,RHS),
3007		preferences:preference(use_smt_mode,SMT),
3008		(SMT=true -> true
3009		; is_for_all_set_membership_predicate(LHS,Parameters,_,_,_)
3010		-> true % optimised processing is available in forall; important for test 1753
3011		),
3012		(\+ ground_state(LocalState) ; \+ ground_state(State)),
3013		% TO DO: check if any of the variables in Condition are not ground
3014		% TO DO: check if used_ids exist in Infos ? memberchk(used_ids(_),Infos),
3015		!,
3016		%print(translating_not_exists_into_forall),nl,print(' '),print_bexpr(LHS),nl, print('=> '),print_bexpr(RHS),nl,
3017		(SMT=true,
3018		is_for_all_set_membership_predicate(RHS,Parameters,_Set,_Pattern,_ParameterValues),
3019		\+ is_for_all_set_membership_predicate(LHS,Parameters,_,_,_)
3020		-> LLHS=RHS, RRHS=LHS % swap LHS and RHS; TO DO: search for membership predicate inside LHS,RHS !!
3021		; LLHS=LHS, RRHS=RHS
3022		),
3023		safe_create_texpr(negation(RRHS),pred,NegRHS),
3024		b_for_all(Parameters,Infos,LLHS,NegRHS,LocalState,State,WF).
3025		b_not_test_exists(Parameters,Condition,Infos,[],[],no_compile,WF) :- !,
3026		% already compiled in is_empty_closure_wf
3027		ground_bexpr_check(Condition,Ground),
3028		b_not_test_exists_aux(Ground,Parameters,Condition, Infos, WF).
3029		b_not_test_exists(Parameters,Condition,Infos,LocalState,State,_,WF) :-
3030		% compile to remove dependency on unused parts of State+LocalState; will make it delay less below
3031		def_get_texpr_ids(Parameters,ParaIDs),
3032		%% print(b_not_test_exists(ParaIDs)),nl, print(state(LocalState,State)),nl, %%
3033	?	b_compiler:b_compile(Condition,ParaIDs,LocalState,State,CompiledCond,WF),
3034		(is_truth(CompiledCond) -> fail
3035		; is_falsity(CompiledCond) -> true
3036		% TO DO: we could detect equalities that will always succeed (but be careful for WD issues)
3037		; ground_bexpr_check(CompiledCond,Ground),
3038		b_not_test_exists_aux(Ground,Parameters,CompiledCond, Infos, WF)
3039		).
3040
3041		:- block b_not_test_exists_aux(-,?,?,?,?).
3042		b_not_test_exists_aux(_,Parameters,CompiledCond,Infos,WF) :-
3043		% getting an idle waitflag considerably slows down test 1739; see also ClearSy/2019_Aug/call_residue/rule_erreur.mch
3044		% slow down no longer the case with the new waitflag implementation
3045		kernel_waitflags:get_idle_wait_flag(b_not_test_exists_aux(Parameters),WF,LWF),
3046		% allow pending co-routines to complete
3047		b_not_test_exists_aux2(LWF,Parameters,CompiledCond,Infos,WF).
3048		:- block b_not_test_exists_aux2(-,?,?,?,?).
3049		b_not_test_exists_aux2(_,Parameters,CompiledCond,Infos,WF) :-
3050		% no need to create inner waitflag: we enumerate fully below: create_inner_wait_flags(WF,b_not_test_exists(Parameters),LocalWF),
3051		%init_wait_flags(LocalWF,[expansion_context(b_not_not_test_exists,Parameters)]),
3052		init_quantifier_wait_flag(WF,not(exists),Parameters,ParaResult,Infos,LocalWF),
3053		not_with_enum_warning(
3054		b_interpreter:b_not_not_test_exists_aux(Parameters,ParaResult,CompiledCond,LocalWF),
3055		LocalWF, CompiledCond, % was not_exists(Parameters), the not_exists quantifier call is on call_stack now
3056		CompiledCond),
3057		copy_wfe_from_inner_if_necessary(LocalWF,WF). % for the case that the negated call has found abort errors and WFE was not grounded
3058		b_not_not_test_exists_aux(Parameters,ParaResult,CompiledCond,LocalWF) :-
3059	?	b_interpreter:set_up_typed_localstate(Parameters,ParaResult,TypedVals,[],NewLocalState,negated),
3060		% delay generation of WD error messages until outer WFE flag set
3061	?	b_interpreter:b_test_boolean_expression(CompiledCond,NewLocalState,[],LocalWF), % check Condition
3062		b_tighter_enumerate_values_in_ctxt(TypedVals,CompiledCond,LocalWF),
3063	?	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
3064		% pending co-routines will be discarded by negation !
3065
3066
3067		/* --------------------------------- */
3068
3069		value_type(_X). % only used in post_conditions (assert_post)
3070		/*
3071		value_type(X) :- nonvar(X),
3072		(X = value(_) ; X = global_set(_) ;
3073		X = global_constant(_) ; X = term(_)).*/
3074
3075
3076		% look up identifiers in store, if the identifier
3077		% is not in the store, assume it's a constant and ignore it
3078		% used for determining wait variables for existential quantifier
3079		% TO DO: better deal with CSE @identifiers ?
3080		lookup_values_if_vars([],_,_,[]).
3081		lookup_values_if_vars([Id|IRest],LocalStore,Store,Values) :-
3082		( lookup_value(Id,LocalStore,Store,Val)
3083		-> (force_evaluation_of_lazy_value(Id,Val,RealVal)
3084		-> Values = [RealVal|VRest]
3085		; Values = [Val|VRest])
3086		; Values = VRest),
3087		lookup_values_if_vars(IRest,LocalStore,Store,VRest).
3088
3089		force_evaluation_of_lazy_value(Id,Value,RealVal) :- nonvar(Value), Value=(Trigger,RealVal),
3090		var(Trigger),
3091		get_preference(use_common_subexpression_elimination,true),
3092		is_lazy_let_identifier(Id),
3093		!,
3094		Trigger=pred_true. % force evaluation, as the exists will otherwise delay/flounder
3095		% Warning: this means that outer lazy_let_expressions inside an exists should be well-defined (WD)
3096
3097
3098		/* will not generate error messages; used for CSP||B when we don't know if something is a B variable or not */
3099		/* TO DO: add peel_prefix for global_sets and constants ?? */
3100		try_lookup_value_in_store_and_global_sets(Id,State,Val) :-
3101		(lookup_value(Id,State,RVal) -> RVal=Val
3102		; b_global_sets:lookup_global_constant(Id,VGC) -> Val = VGC
3103		; b_global_set_or_free_type(Id,_AnyType,Value) -> Val=Value /* global set evaluates to itself */
3104		).
3105
3106
3107		lookup_value_in_store_and_global_sets_wf(Id,Type,LocalState,State,Val,Span,WF) :-
3108		(lookup_value_with_span_wf(Id,LocalState,State,RVal,Span,WF)
3109		-> RVal=Val
3110		; lookup_value_in_global_sets_wf(Id,Type,Val,LocalState,State,Span,WF)
3111		).
3112
3113		lookup_value_in_global_sets_wf(Id,Type,Val,LocalState,State,Span,WF) :-
3114		(b_global_sets:lookup_global_constant(Id,VGC)
3115		-> Val=VGC
3116	?	; (b_global_set_or_free_type(Id,Type,Value)
3117		-> Val = Value /* global set evaluates to itself */
3118		; ((member(bind(Id,_),LocalState) ; member(bind(Id,_),State))
3119		-> Msg1 = 'Cannot determine value for identifier '
3120		; Msg1 = 'Cannot find identifier '
3121		),
3122		append(LocalState,State,LSS),
3123		translate:translate_bstate_limited(LSS,StateInfo),
3124		ajoin([Msg1,Id,':'],Msg),
3125		add_error_wf(identifier_not_found,Msg,StateInfo,Span,WF),
3126		fail % Val = term(Id) /* Val=fail */
3127		)
3128		).
3129
3130		:- use_module(probsrc(kernel_freetypes),[registered_freetype/2, registered_freetype_case_value/3]).
3131	?	b_global_set_or_free_type(Id,_,global_set(Id)) :- b_global_set(Id).
3132		b_global_set_or_free_type(Id,_,freetype(Id)) :- registered_freetype(Id,_).
3133		b_global_set_or_free_type(Id,Type,Value) :-
3134		registered_freetype_case_value(Id,Type,Value). % to instantiate the type parameters we also need the TypeId
3135		% TODO: we could also register Event-B destructors and look them up here
3136
3137		/* -----------------------------*/
3138		/* b_compute_expressions */
3139		/* -----------------------------*/
3140
3141		b_compute_expressions([], _, _, [],_WF).
3142		b_compute_expressions([EXPRsHd|EXPRsTl],LocalState,InState,[ValHd|ValTl],WF) :-
3143	?	b_compute_expression(EXPRsHd,LocalState,InState,ValHd,WF),
3144	?	b_compute_expressions(EXPRsTl,LocalState,InState,ValTl,WF).
3145
3146		% a variation of above that delays computing the expressions until Waitflag 1/2 is set
3147		b_compute_assign_expressions_when(EXPRsTl,LocalState,InState,ValTl,WF,OR) :-
3148		get_assign_expr_priority_wf(OR,WF,LWF),
3149	?	b_compute_expressions_when2(EXPRsTl,LocalState,InState,ValTl,WF,LWF).
3150		b_compute_expressions_when2([], _, _, [],_WF,_).
3151		b_compute_expressions_when2([EXPRsHd|EXPRsTl],LocalState,InState,[ValHd|ValTl],WF,LWF) :-
3152	?	b_compute_expression_when2(EXPRsHd,LocalState,InState,ValHd,WF,LWF),
3153		b_compute_expressions_when2(EXPRsTl,LocalState,InState,ValTl,WF,LWF).
3154
3155		% TO DO: add step number in OR
3156		get_assign_expr_priority_wf(output_required,_WF,LWF) :- !,
3157		% the Output of the statement is required; do not delay computing it
3158		LWF=0. % this would delay computation until WF0 is set: get_wait_flag0(WF,LWF); cf. initialisation for test 2104
3159		get_assign_expr_priority_wf(_,WF,LWF) :-
3160		% the Output is not directly required; compute it later (when we are sure that the statement actually succeeds)
3161		(preferences:preference(use_smt_mode,true)
3162		-> Prio = 2.0 % SMT Mode: we are probably doing CBC checking, we may have set up constraints on ValTl
3163		; 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
3164		get_wait_flag(Prio,get_assign_expr_priority_wf,WF,LWF).
3165
3166		:- block b_compute_expression_when2(?,?,?,?,?,-).
3167		b_compute_expression_when2(eval_must_not_fail(ErrMsg,EXPRsHd),LocalState,InState,Res,WF,_) :- !,
3168		% catch failure; in case the interpreter fails to catch wd-error itself (e.g., try_find_abort is false)
3169		if(b_compute_expression(EXPRsHd,LocalState,InState,ValHd,WF),equal_object_wf(ValHd,Res,WF),
3170		(translate:translate_bexpression_with_limit(EXPRsHd,TS),
3171		add_wd_error_span(ErrMsg,TS,span_predicate(EXPRsHd,LocalState,InState),WF))).
3172		b_compute_expression_when2(EXPRsHd,LocalState,InState,ValHd,WF,_) :-
3173		copy_wf_start(WF,b_compute_expression_when2,CWF), % not sure this is useful for expressions:
3174	?	b_compute_expression(EXPRsHd,LocalState,InState,ValHd,CWF),
3175	?	copy_wf_finish(WF,CWF).
3176
3177
3178		/* -----------------------------*/
3179		/* b_execute_statement */
3180		/* -----------------------------*/
3181		/* b_execute_statement(XMLStatements:input, StateofLocalVariables:input,
3182		StateOfGlobalVariables:input,
3183		ListOfUpdateBindingsForGlobalVariablesAndResultVariables:output) */
3184
3185		:- assert_pre(b_interpreter:b_execute_statement(Stmt,LS,IS,_OS,_WF,_Path,_OR),
3186		(bsyntaxtree:check_if_typed_substitution(Stmt),type_check(LS,store),type_check(IS,store) )).
3187		:- assert_post(b_interpreter:b_execute_statement(_Stmt,_LS,_IS,OS,_WF,_Path,_OR),
3188		(type_check(OS,store))).
3189
3190		b_execute_inner_statement(Body,LocalState,InState,OutState,WF,Path,output_required) :-
3191		get_texpr_expr(Body,BE),
3192		BE \= while(_COND,_STMT,_INV,_VARIANT), % also other non-det substitutions ??
3193		BE \= select(_),
3194		BE \= select(_,_),
3195		BE \= if(_), % case(_,_,_) statements are now translated to if-then-else in ast_cleanup
3196		!,
3197		get_wait_flag0(WF,WF0),
3198		block_execute_statement(WF0,Body,LocalState,InState,OutState,WF,Path).
3199		b_execute_inner_statement(Body,LocalState,InState,OutState,WF,Path,OR) :-
3200		get_wait_flag(2,inner_stmt,WF,LWF), % was 2.0
3201		clone_wait_flags_from1(WF,GroundUponFinish,InnerWF), % copy everything but WF0
3202		b_execute_inner_statement(Body,LocalState,InState,OutState,GroundUponFinish,InnerWF,Path,LWF,OR).
3203
3204		:- block block_execute_statement(-, ?,?,?, ?,?,?).
3205		block_execute_statement(_,Body,LocalState,InState,OutState,WF,Path) :-
3206	?	b_execute_statement(Body,LocalState,InState,OutState,WF,Path,output_required).
3207
3208		:- block b_execute_inner_statement(?,?,?,?,?,?,?,-,?).
3209		b_execute_inner_statement(Body,LocalState,InState,OutState,GUF,InnerWF,Path,_,OR) :-
3210	?	b_execute_statement(Body,LocalState,InState,OutState,InnerWF,Path,OR),
3211		(GUF=ground_upon_finish -> ground_wait_flags(InnerWF) ; ground_wait_flag0(InnerWF)).
3212
3213		:- use_module(source_profiler,[opt_add_source_location_hits/2]).
3214		:- use_module(b_operation_guards,[get_substitution_enabling_condition/4]).
3215
3216
3217		b_execute_statement_nowf(Subst,LS,S,OutS,Ctxt) :-
3218		init_wait_flags_with_call_stack(WF,[prob_command_context(Ctxt,unknown)]),
3219		b_interpreter:b_execute_statement(Subst,LS,S,OutS,WF,_Path),
3220		ground_wait_flags(WF).
3221
3222		b_execute_statement(Stmt, LS, S, OS, WF,Path) :-
3223	?	b_execute_statement(Stmt, LS, S, OS, WF,Path,output_not_required).
3224		b_execute_statement(b(Stmt,_,Infos), LS, S, OS, WF,Path,OR) :- !,
3225	?	b_execute_statement2(Stmt, Infos, LS, S, OS, WF,Path,OR).
3226		b_execute_statement(Stmt, LS, S, OS, WF,Path,OR) :-
3227		add_internal_error('Statement not properly wrapped: ',b_execute_statement(Stmt, LS, S, OS, WF,Path,OR)),
3228		b_execute_statement2(Stmt, [], LS, S, OS, WF,Path,OR).
3229
3230		% blocks should be removed by type-checker
3231		b_execute_statement2(block(Stmt),_,LS,IS,OS,WF,Path,OR) :- !,
3232		b_execute_statement(Stmt,LS,IS,OS,WF,Path,OR). %% NOT COVERED
3233		b_execute_statement2(assign(LHS,Exprs),Info,LocalState,InState,OutState,WF,assign(LHS,VALs),OR) :- !,
3234		/* Var1, ..., VarN := Expr1, ..., ExprN */
3235		/* also: Var1, fun1(arg), ... := Expr1, Expr2, ... */
3236		opt_add_source_location_hits(Info,1),
3237	?	b_compute_assign_expressions_when(Exprs,LocalState,InState,VALs,WF,OR),% VALs - a list of computed values
3238	?	b_assign_values_or_functions(LHS,VALs,LocalState,InState,OutState,WF,OR).
3239		b_execute_statement2(assign_single_id(IDE,Expr),Info,LocalState,InState,OutState,WF,assign_single_id(ID,Value),_OR) :-
3240		get_texpr_id(IDE,ID),!,
3241		opt_add_source_location_hits(Info,1),
3242	?	b_compute_expression(Expr,LocalState,InState,Value,WF), % b_compute_assign_expressions_when
3243		%b_compute_assign_expressions_when([Expr],LocalState,InState,[Value],WF),
3244		OutState=[bind(ID,Value)].
3245		b_execute_statement2(choice(ChoiceList),_,LocalState,InState,OutState,WF,Path,OR) :- !,
3246		/* CHOICE LHS OR RHS OR ... END */
3247		get_wait_flag(2,choice,WF,WFC), % % was 2.0, maybe use length of ChoiceList as Priority ??
3248		b_execute_choice(ChoiceList,LocalState,InState,OutState,WF,Path,WFC,OR).
3249		b_execute_statement2(becomes_element_of(LHS,RHS), /* LHS :: RHS */
3250		Info,LocalState,InState,OutState,WF,Path,_OR) :- !,
3251		% LHS must be of the form Var1,..,Vark where all variables are disjoint
3252		opt_add_source_location_hits(Info,1),
3253		b_execute_becomes_element_of(LHS,RHS,LocalState,InState,OutState,WF,Path).
3254		b_execute_statement2(becomes_such(Vars,Condition),Info,LocalState,InState,OutState,WF,Path,OR) :- !,
3255		/* Vars : (Condition) */
3256		opt_add_source_location_hits(Info,1),
3257		(OR=output_required, get_preference(expand_becomes_such_into_set,true) % see test 1770
3258		-> % compute all solutions of the Condition predicate and then choose amongst them;
3259		% possibly good for complex preds, ensures we solve local constraints in isolation in context of sequence(.)
3260		% runs into time_out for test 2093; TODO: detect special patterns like partial_function, ...
3261		insert_before_substitution_variables(Vars,LocalState,InState,LocalState,TempLocalState),
3262		add_debug_message(b_interpreter,'Expanding become_such predicate into set: ',Condition,Condition),
3263		b_compute_comprehension_set(Vars,Condition,Info,TempLocalState,InState,CResult,WF),
3264		RHS = b(value(CResult),any,[was(becomes_such)]),
3265		b_execute_statement2(becomes_element_of(Vars,RHS), Info,LocalState,InState,OutState,WF,Path,OR)
3266		; % create Vars in State and assert that Condition is true; probably good for cbc checking
3267	?	b_execute_becomes_such(Vars,Condition,Info,LocalState,InState,OutState,_,Path,WF)
3268		).
3269		b_execute_statement2(sequence(Seq), /* LHS ; RHS */
3270		_,LocalState,InState,OutUpdates,WF,Path,OR) :- !, %pe_print(sequence(Seq,InState)),
3271	?	b_execute_sequence(Seq,LocalState,InState,OutUpdates,WF,Path,OR).
3272		b_execute_statement2(precondition(PreCond,Body),_,LocalState,InState,OutState,WF,Path,OR) :- !,
3273		%print('*** Non-outermost PRE construct'),nl,
3274		Path=pre(PreRes,IPath),
3275		b_try_check_boolean_expression(PreCond,LocalState,InState,WF,PreRes),
3276		%used to be: ground_det_wait_flag(WF),
3277		check_precondition_result(PreRes,PreCond,LocalState,InState,WF),
3278	?	(PreRes == pred_true -> b_execute_statement(Body,LocalState,InState,OutState,WF,IPath,OR)
3279		; PreRes == pred_false -> IPath = not_executed
3280		; b_execute_inner_statement(Body,LocalState,InState,OutState,WF,IPath,OR) % with extra waitflag
3281		).
3282		b_execute_statement2(assertion(PreCond,Body),_,LocalState,InState,OutState,WF,Path,OR) :- !,
3283	?	b_execute_assertion(PreCond,Body,LocalState,InState,OutState,WF,Path,OR).
3284		b_execute_statement2(witness_then(PreCond,Body),_,LocalState,InState,OutState,WF,witness(Path),OR) :- !,
3285		b_test_boolean_expression(PreCond,LocalState,InState,WF),
3286		b_execute_inner_statement(Body,LocalState,InState,OutState,WF,Path,OR).
3287		b_execute_statement2(select(Whens),_, LocalState, InState, OutState,WF,select(Nr,Path),OR) :- !,
3288		get_texpr_expr(TExpr,select_when(PreCond, Body)), % info field not used for select_when
3289	?	optimized_nth1(Nr, Whens, TExpr), % THIS IS A CHOICE POINT if length(Whens)>1 ! <-------- TO DO guard
3290	?	b_test_boolean_expression(PreCond,LocalState,InState,WF),
3291		%used to call: ground_det_wait_flag(WF), now execute inner statement delays
3292		b_execute_inner_statement(Body,LocalState,InState,OutState,WF,Path,OR).
3293		b_execute_statement2(select(Whens,Else), Infos, LocalState, InState, OutState,WF,Path,OR) :- !,
3294		(
3295	?	b_execute_statement2(select(Whens), Infos, LocalState, InState, OutState,WF,Path,OR)
3296		; % THIS IS A CHOICE POINT ! <-------- TO DO guard
3297		findall(PC,
3298		(member(SW,Whens),get_texpr_expr(SW,select_when(PC,_))), AllPreconds),
3299		b_not_test_list_of_boolean_expression(AllPreconds,LocalState,InState,WF),
3300		Path = select(else,IPath),
3301		b_execute_inner_statement(Else,LocalState,InState,OutState,WF,IPath,OR)
3302		).
3303		b_execute_statement2(var(Parameters,Body), /* VAR _ IN _ substitution */
3304		_,LocalState,InState,NewOutState,WF,var(Names,Path),OR) :- !,
3305		/* introduces a new variable that can be assigned to */
3306		split_names_and_types(Parameters,Names,_),
3307		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 !!
3308		% otherwise we may think there are two updates, e.g., in WHILE loop; see Rule_DB_SIGAREA_0030 from test 1303
3309		set_up_undefined_localstate(Parameters,InState1,NewInState),
3310		delete_variables_from_state(Names,LocalState,NewLocalState),
3311		%check_valid_store(InState,var_in_state), check_valid_store(LocalState,var_local_state),
3312	?	b_execute_statement(Body,NewLocalState,NewInState,OutState,WF,Path,OR),
3313		% check_valid_store(OutState,var_out_state),
3314		filter_results(Parameters,OutState,NewOutState,WF)
3315		.
3316		/* it can be ok not to assign to a local variable */
3317
3318		%TODO(DP, 5.8.2008):
3319		b_execute_statement2(let(Parameters,Defs,Body), /* LET _ BE _ IN _ */
3320		_,LocalState,InState,OutState,WF,let(Path),OR) :- !,
3321	?	set_up_typed_localstate(Parameters,LocalState,NewLocalState),
3322		b_execute_let_definitions(Defs,NewLocalState,InState,WF),
3323	?	b_execute_statement(Body,NewLocalState,InState,OutState,WF,Path,OR).
3324		b_execute_statement2(lazy_let_subst(Id,IdExpr,Body),_,LocalState,InState,OutState,WF,lazy_let(Path),OR) :-
3325		!,
3326		add_lazy_let_id_and_expression(Id,IdExpr,LocalState,InState,NewLocalState,WF),
3327		b_execute_statement(Body,NewLocalState,InState,OutState,WF,Path,OR).
3328		b_execute_statement2(any(Parameters,PreCond,Body), /* ANY _ WHERE */
3329		Info,LocalState,InState,OutState,WF0,any(Bindings,Path),OR) :- !, %statistics(runtime,_),
3330		%print('ANY: '), print_bexpr(PreCond),nl, %%
3331	?	set_up_typed_localstate(Parameters,FreshVars,TypedVals,LocalState,NewLocalState,positive),
3332		create_any_bindings(Parameters,FreshVars,Bindings),
3333		push_wait_flag_call_stack_info(WF0,quantifier_call('ANY',Parameters,FreshVars,Info),WF),
3334	?	b_test_inner_boolean_expression(PreCond,NewLocalState,InState,WF), /* check WHERE */
3335		%%observe_state(TypedVals,WF,0), b_tracetest_boolean_expression(PreCond,NewLocalState,InState,WF,one), %% comment in for debugging
3336		b_tighter_enumerate_all_values(TypedVals,WF), % moved enumeration after test; in case WF already instantiated
3337		%TODO: check if we can use b_tighter_enumerate_values_in_ctxt
3338	?	b_execute_statement(Body,NewLocalState,InState,OutState,WF,Path,OR). /* should we use b_execute_inner_statement/LWF here ?? */
3339		b_execute_statement2(skip, /* SKIP */
3340		Info,_LocalState,_InState,OutState,_WF,skip,_OR) :- !,
3341		opt_add_source_location_hits(Info,1),
3342		OutState = [].
3343		b_execute_statement2(parallel(Statements), /* LHS || RHS */ %@@@
3344		_,LocalState,InState,OutState,WF,parallel(Paths),OR) :- !,
3345	?	b_execute_statements_in_parallel(Statements,LocalState,InState,OutState,WF,Paths,OR).
3346		b_execute_statement2(init_statement(Stmt),_,LocalState,InState,OutState,WF,Path,OR) :- !,
3347		/* Like block: but
3348		writes error messages if statement fails */ %@@@
3349		(get_preference(provide_trace_information,true)
3350		-> nl,print(' =INIT=> '),translate:print_subst(Stmt),nl, flush_output(user_output),
3351		statistics(walltime,[Tot1,_])
3352		; true),
3353	?	if(b_execute_initialisation_statement(Stmt,LocalState,InState,OutState,WF,Path,OR),
3354		(
3355		(get_preference(provide_trace_information,true)
3356		-> statistics(walltime,[Tot2,_]), Tot is Tot2-Tot1,
3357		format(' [=OK= ~w ms]~n',[Tot]), flush_output(user_output)
3358		; true)
3359		),
3360		( translate:translate_substitution(Stmt,TStmtStr),
3361		(bmachine:b_machine_temp_predicate(_TempPred)
3362		-> Msg = 'INITIALISATION statement cannot be executed with extra predicate: ',
3363		add_error_wf(initialisation_fails,Msg,TStmtStr,Stmt,WF)
3364		% do not add as state error; user requested transition
3365		; Msg = 'INITIALISATION statement fails: ',
3366		(get_substitution_enabling_condition(Stmt,SpanPred,_BSVars,_IsPreciseV)
3367		-> %insert_custom_predicate_into_guard(EnablingCondition,TempPred,SpanPred),
3368		ErrPos = span_predicate(SpanPred,LocalState,InState) % for visualising by user
3369		% Note: user can also visualise by chooise execute by predicate (in TK)
3370		; ErrPos = Stmt
3371		),
3372		% add as state error so that we can visualise span predicate
3373		add_state_error_wf(initialisation_fails,Msg,TStmtStr,ErrPos,WF) % cf test 1736 and 278
3374		%add_error_wf(initialisation_fails,Msg,TStmtStr,ErrPos,WF)
3375		),
3376		fail
3377		)
3378		).
3379		b_execute_statement2(if(IfList),_,LocalState,InState,OutState,WF,Path,OR) :- !,
3380		LWF='$GENERATE_ON_DEMAND',
3381	?	b_execute_else_list(IfList,LocalState,InState,OutState,WF,1,Path,LWF,OR).
3382		b_execute_statement2(operation_call(Operation,Results,Parameters),Info,LocalState,InState,OutState,WF,
3383		operation_call(OperationName,Results,ParamValues,ResultValues,InnerPath),OR) :- !,
3384		def_get_texpr_id(Operation,op(OperationName)),
3385	?	b_execute_operation_with_parameters(OperationName,LocalState,InState,Results,
3386		Parameters,OpOutState,ParamValues,ResultValues,InnerPath,Info,WF,OR),
3387		opt_add_source_location_hits(Info,1),
3388		split_names_and_types(Results,ResultingIDs,_),
3389		store_values(ResultingIDs, ResultValues, ResultsOutState),
3390		combine_updates(ResultsOutState,OpOutState,OutState).
3391
3392		b_execute_statement2(while(COND,STMT,INV,VARIANT),
3393		Info,LocalState,InState,OutState,WF0,while(VarVal,BodyPath),_OR) :- !,
3394		%hit_profiler:add_profile_hit(while(COND,WF),2),
3395		% we may go around the loop many times: avoid carrying around unused variables
3396		get_while_reads_write_info_and_filter_state(Info,LocalState,InState,LS,IS,ModVars),
3397		push_wait_flag_call_stack_info(WF0,b_operator_call('WHILE',[VarVal],Info),WF), % TODO: provide subst. call stack entry
3398		%print_message(execute_while(LocalState,InState)),
3399		b_compiler:b_optimize(INV,ModVars,LS,IS,CINV,WF),
3400		b_compiler:b_optimize(COND,ModVars,LS,IS,CCOND,WF),
3401		b_compiler:b_optimize(VARIANT,ModVars,LS,IS,CVARIANT,WF),
3402		%,b_compiler:b_compile(STMT,ModVars,LS,IS,CSTMT,WF)
3403		% TO DO: maybe exclude in one go; use ordered approach ?
3404		%exclude(unused_variable(ModVars),LS,LS2), % only keep modified vars; all other compiled
3405		%exclude(unused_variable(ModVars),IS,IS2), % only keep modified vars; all other compiled
3406		b_compute_expression(CVARIANT,LS,IS,VarVal,WF),
3407		b_execute_while(CCOND,STMT,CINV,CVARIANT,ModVars,VarVal,LS,IS,OutState,WF,BodyPath).
3408		b_execute_statement2(external_subst_call(FunName,Args),Info,LocalState,State,OutState,WF,external_subst(FunName),_OR) :-
3409		!, b_compute_expressions(Args, LocalState,State, EvaluatedArgs, WF),
3410		push_wait_flag_call_stack_info(WF,external_call(FunName,EvaluatedArgs,Info),WF2),
3411		call_external_substitution(FunName,EvaluatedArgs,State,OutState,Info,WF2).
3412		b_execute_statement2(E,I,LS,S,O,WF,Path,OR) :-
3413		add_internal_error('Uncovered statement: ',b_execute_statement2(E,I,LS,S,O,WF,Path,OR)),
3414		print_functor(E),nl,fail.
3415
3416		% -------------------
3417
3418		b_execute_becomes_element_of(LHS,RHS,LocalState,InState,OutState,WF,becomes_element_of(LHS,SingleValue)) :-
3419		b_compute_expression(RHS,LocalState,InState,ValueSet,WF),
3420		(get_preference(warn_about_failing_assignments,false)
3421		-> b_execute_becomes_element_of_aux(LHS,SingleValue,ValueSet,OutState,WF)
3422		; if(b_execute_becomes_element_of_aux(LHS,SingleValue,ValueSet,OutState,WF),
3423		true,
3424		(add_feasibility_error(b(not_equal(RHS,b(empty_set,any,[])),pred,[]),
3425		'Assignment by set (becomes_element_of) fails:', LocalState,InState,WF),
3426		SingleValue = term(undefined),
3427		OutState = [] % pretend no assignment occurred (skip)
3428		))
3429		).
3430		b_execute_becomes_element_of_aux(LHS,SingleValue,ValueSet,OutState,WF) :-
3431		convert_pairs_into_list(LHS,SingleValue,ValList),
3432		set_up_typed_localstate(LHS,ValList,TypedVals,[],OutState,positive),
3433		check_element_of_wf(SingleValue,ValueSet,WF),
3434		ground_det_wait_flag(WF), %% TODO: remove this
3435		b_tighter_enumerate_all_values(TypedVals,WF).
3436
3437		:- use_module(b_interpreter_components,[construct_optimized_exists/3]).
3438		b_execute_becomes_such(Vars,Condition,Info,LocalState,InState,OutState,Values,becomes_such(Ids,Values),WF) :- !,
3439		% create the LHS variables in the local state
3440	?	set_up_typed_localstate(Vars,Values,TypedVals,LocalState,TempLocalState1,positive),
3441		get_texpr_ids(Vars,Ids),
3442		% there might be some variables of the form x$0 to access the
3443		% values before the substitution. We put them into the local state
3444		insert_before_substitution_variables(Vars,LocalState,InState,TempLocalState1,TempLocalState),
3445		push_wait_flag_call_stack_info(WF,quantifier_call(':(_)',Vars,Values,Info),WF1),
3446		(get_preference(warn_about_failing_assignments,false)
3447		-> % store those values also into the outgoing state as bind/2 pairs
3448		store_values(Ids,Values,OutState),
3449	?	b_test_inner_boolean_expression(Condition,TempLocalState,InState,WF1),
3450		b_tighter_enumerate_values_in_ctxt(TypedVals,Condition,WF1)
3451		; if((store_values(Ids,Values,OutState),
3452		b_test_inner_boolean_expression(Condition,TempLocalState,InState,WF1),
3453		b_tighter_enumerate_values_in_ctxt(TypedVals,Condition,WF1)),
3454		true, % Note: the predicate could still fail later when WF1 is instantiated !
3455		(construct_optimized_exists(Vars,Condition,EC,false),
3456		add_feasibility_error(EC,'Assignment by predicate (becomes_such) fails:',TempLocalState,InState,WF1),
3457		OutState = [] % pretend no assignment occurred (skip)
3458		)
3459		)
3460		).
3461		% moved enumeration after test, to avoid overhead in case Condition is deterministic
3462		% (see e.g. WhileAssignTupleChoose_v2)
3463
3464		add_feasibility_error(Condition,Msg,LS,S,WF) :-
3465		translate_bexpression(Condition,CS),
3466		add_abort_error_span(feasibility_error, Msg, CS,span_predicate(Condition,LS,S),WF).
3467
3468		b_execute_sequence([],_LocalState,_InState,[],_WF,[],_OR).
3469		b_execute_sequence([First|Rest],LocalState,InState,OutUpdates,WF,Path,OR) :-
3470		(Rest == []
3471	?	-> b_execute_statement(First,LocalState,InState,OutUpdates,WF,Path,OR)
3472		; Path = sequence(Path1,RestPath),
3473	?	b_execute_statement(First,LocalState,InState,LHSUpdates,WF,Path1,output_required),
3474	?	ground_det_wait_flag(WF), % maybe better to delay next execute_statement ? TODO
3475		store_intermediate_updates_wf(InState,LHSUpdates,IntermediateState,First,WF),
3476		% TO DO: statically determine what Rest can modify and copy LHSUpdates not modified by Rest into OutUpdates
3477	?	b_execute_statement_list_when_state_set(Rest,LocalState,IntermediateState,
3478		LHSUpdates,OutUpdates,WF,RestPath,OR)
3479		).
3480
3481
3482		:- block check_precondition_result(-,?,?,?,?).
3483		check_precondition_result(pred_true,_,_,_,_).
3484		check_precondition_result(pred_false,PreCond,LS,S,WF) :-
3485		translate_bexpression(PreCond,PreString),
3486		add_abort_error_span(precondition_error,'Precondition violated: ',PreString,span_predicate(PreCond,LS,S),WF).
3487
3488		create_any_bindings([],[],[]).
3489		create_any_bindings([Param|Prest],[Value|Vrest],[bind(Id,Value)|Brest]) :-
3490		get_texpr_id(Param,Id),
3491		create_any_bindings(Prest,Vrest,Brest).
3492
3493		% insert the values of variables before the substitution under an
3494		% alternative name. The alternative name is given as an optional extra
3495		% information in the variable (see type-checking of becomes_such for
3496		% details). Usually (i.e. always) the alternative name is x$0 for the variable x.
3497		insert_before_substitution_variables([],_LocalState,_InState,State,State).
3498		insert_before_substitution_variables([Var|VRest],LocalState,InState,StateA,ResultStateB) :-
3499		get_texpr_info(Var,Infos),
3500	?	( member(before_substitution(_,Alternative),Infos) ->
3501		def_get_texpr_id(Var,Id),
3502		lookup_value_for_existing_id(Id,LocalState,InState,Value),
3503		store_value(Alternative,Value,StateA,StateC)
3504		;
3505		StateA = StateC),
3506		insert_before_substitution_variables(VRest,LocalState,InState,StateC,ResultStateB).
3507
3508
3509
3510		% treat the bool(.) operator
3511		b_convert_bool(Pred,LocalState,State,WF,PredRes) :-
3512		get_wait_flag0(WF,WF0), % first give a chance for PredRes to be instantiated
3513	?	b_convert_bool_wf0(Pred,LocalState,State,WF,PredRes,WF0).
3514
3515		:- block b_convert_bool_wf0(?,?,?,?,-,-).
3516		b_convert_bool_wf0(Pred,LocalState,State,WF,PredRes,_) :- PredRes==pred_true,!,
3517		%% print('bool(.)=TRUE '), translate:print_bexpr(Pred),nl, %%
3518	?	b_test_inner_boolean_expression(Pred,LocalState,State,WF).
3519		b_convert_bool_wf0(Pred,LocalState,State,WF,PredRes,_) :- PredRes==pred_false,!,
3520		%% print('bool(.)=FALSE '), translate:print_bexpr(Pred),nl, %%
3521	?	b_not_test_inner_boolean_expression(Pred,LocalState,State,WF).
3522		b_convert_bool_wf0(Pred,LocalState,State,WF,PredRes,_) :-
3523		%% print('bool(.) check : '), translate:print_bexpr(Pred),nl, % obsv(LocalState),
3524	?	b_try_check_boolean_expression_wf(Pred,LocalState,State,WF,PredRes ).
3525		%% print('finished bool(.) check : '), translate:print_bexpr(Pred),nl,translate:print_bstate(LocalState),nl.
3526
3527		% Additional time limit +TO in ms, e.g., used for CDCL(T). +TORes is time_out if a timeout occurred.
3528		b_convert_bool_timeout(Pred,LocalState,State,WF,PredRes,TO,TORes) :-
3529		get_wait_flag0(WF,WF0),
3530		b_convert_bool_wf0_timeout(Pred,LocalState,State,WF,PredRes,WF0,TO,TORes).
3531
3532		:- block b_convert_bool_wf0_timeout(?,?,?,?,-,-,?,?).
3533		b_convert_bool_wf0_timeout(Pred,LocalState,State,WF,PredRes,_,TO,TORes) :-
3534		PredRes == pred_true,
3535		!,
3536		safe_time_out(b_test_inner_boolean_expression(Pred,LocalState,State,WF),
3537		TO,
3538		TORes).
3539		b_convert_bool_wf0_timeout(Pred,LocalState,State,WF,PredRes,_,TO,TORes) :-
3540		PredRes == pred_false,
3541		!,
3542		safe_time_out(b_not_test_inner_boolean_expression(Pred,LocalState,State,WF),
3543		TO,
3544		TORes).
3545		b_convert_bool_wf0_timeout(Pred,LocalState,State,WF,PredRes,_,TO,TORes) :-
3546		safe_time_out(b_try_check_boolean_expression_wf(Pred,LocalState,State,WF,PredRes ),
3547		TO,
3548		TORes).
3549
3550		%%obsv([]).
3551		%%obsv([bind(Var,Val) | T] ) :- when(ground(Val), format("~w = ~w~n",[Var,Val])), obsv(T).
3552
3553		% check boolean expression without enumeration predicate result (unless WFE is set)
3554		b_try_check_boolean_expression_no_enum_wf(Pred,LocalState,State,WF,PredRes) :-
3555	?	b_try_check_boolean_expression_lwf(Pred,LocalState,State,WF,'$NO_ENUMERATION',PredRes,_).
3556
3557		b_try_check_boolean_expression_wf(Pred,LocalState,State,WF,PredRes) :-
3558	?	b_try_check_boolean_expression_lwf(Pred,LocalState,State,WF,'$ENUMERATION',PredRes,'$GENERATE_ON_DEMAND' ).
3559		% try to do check_boolean expression; if not possible create choice point if LWF is grounded
3560		b_try_check_boolean_expression_lwf(Pred,LocalState,InState,WF,DoEnumeration,PredRes,LWF) :-
3561	?	b_compiler:b_optimize(Pred,[],LocalState,InState,CPRED,WF), % this increases chance that check can be applied+avoids multiple computations in two branches
3562		% still: some computations may not be pre-computed, e.g., union of closures, ..., see Rule_DB_PSR_0003_C
3563	?	b_try_check_boolean_expression_lwf_c(CPRED,LocalState,InState,WF,DoEnumeration,PredRes,LWF).
3564
3565		b_try_check_boolean_expression_lwf_c(b(truth,_,_),_LocalState,_InState,_WF,_,PredRes,_LWF) :- !,
3566		% typical case in e.g. IF-THEN-ELSE
3567		PredRes= pred_true.
3568		b_try_check_boolean_expression_lwf_c(Pred,LocalState,InState,WF,DoEnumeration,PredRes,LWF) :-
3569		copy_wf_start(WF,try_check,CWF),
3570	?	if(b_check_boolean_expression_with_enum(Pred,LocalState,InState,CWF,DoEnumeration,Res),
3571		% Note: we do not use a cut here ! usually b_check will not enumerate; but on rare occasions it can (apply function in inverse,...)
3572		(PredRes=Res,
3573	?	copy_wf_finish(WF,CWF)
3574		),
3575		b_try_check_failed(Pred,LocalState,InState,WF,DoEnumeration,PredRes,LWF)
3576		).
3577		b_try_check_failed(Pred,LocalState,InState,WF,DoEnumeration,PredRes,LWF) :-
3578		% print(choice_point(LWF)),nl, translate:print_bexpr(Pred),nl,
3579		perfmessagecall(choice_point,reification_of_check_predicate_failed,translate:print_bexpr(Pred),Pred),
3580		(LWF=='$GENERATE_ON_DEMAND' -> get_binary_choice_wait_flag('$GENERATE_ON_DEMAND',WF,WF1)
3581		; var(LWF),DoEnumeration=='$NO_ENUMERATION' -> get_enumeration_finished_wait_flag(WF,WF1) % nothing will enum LWF
3582		; WF1=LWF),
3583		b_try_check_boolean_expression_lwf_block(Pred,LocalState,InState,WF,PredRes,WF1).
3584
3585		% a version of b_check_boolean_expression which will enumerate its result as last resort
3586		% should we only do this in SMT mode : preferences:preference(use_smt_mode,true) ?
3587		b_check_boolean_expression_with_enum(Pred,LocalState,State,WF,DoEnumeration,Res) :-
3588	?	b_check_boolean_expression(Pred,LocalState,State,WF,Res),
3589		(nonvar(Res) -> true
3590		; DoEnumeration=='$NO_ENUMERATION' -> get_enumeration_finished_wait_flag(WF,EWF), enum_pred_result(Res,EWF,WF)
3591		; get_wait_flag0(WF,LWF0),
3592		enum_pred_result0(Res,LWF0,WF)).
3593
3594		% first set up with wait_flag0: easy to get, avoid putting unnecessary waitflags into store
3595		% relevant for DataValidationTest.mch with n>20000
3596		:- block enum_pred_result0(-,-,?).
3597		enum_pred_result0(Res,_,WF) :- var(Res),!,
3598		get_last_wait_flag(b_check_boolean_expression_with_enum,WF,LWF),
3599		enum_pred_result(Res,LWF,WF). % before doing infinite enumerations: better do case-distinction here
3600		enum_pred_result0(_,_,_).
3601
3602		:- block enum_pred_result(-,-,?).
3603		enum_pred_result(pred_true,_,_).
3604		enum_pred_result(pred_false,_,_).
3605
3606		:- block b_try_check_boolean_expression_lwf_block(?,?,?, ?,-,-).
3607		b_try_check_boolean_expression_lwf_block(Pred,LocalState,InState,WF,PREDRES,_) :-
3608		PREDRES \== pred_false,
3609		% print(' TRUE +++++> '), translate:print_bexpr(Pred),nl,
3610	?	b_test_inner_boolean_expression(Pred,LocalState,InState,WF),
3611		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
3612		b_try_check_boolean_expression_lwf_block(Pred,LocalState,InState,WF,PREDRES,_) :-
3613		PREDRES \== pred_true,
3614		% print(' FALSE +++++> '), translate:print_bexpr(Pred),nl,
3615	?	b_not_test_inner_boolean_expression(Pred,LocalState,InState,WF),
3616		PREDRES = pred_false.
3617
3618		% try to do check_boolean expression; if not possible create choice point *directly*
3619		b_try_check_boolean_expression(Pred,LocalState,InState,WF,PredRes) :-
3620		b_compiler:b_optimize(Pred,[],LocalState,InState,CPRED,WF), % this increases chance that check can be applied+avoids multiple computations in two branches
3621		b_try_check_boolean_expression_c(CPRED,LocalState,InState,WF,PredRes).
3622		b_try_check_boolean_expression_c(Pred,LocalState,InState,WF,PredRes) :-
3623		copy_wf_start(WF,try_check_c,CWF),
3624		if(b_check_boolean_expression(Pred,LocalState,InState,CWF,Res),
3625		(PredRes=Res,copy_wf_finish(WF,CWF)),
3626	?	b_try_check_boolean_expression_c2(Pred,LocalState,InState,WF,PredRes)
3627		).
3628		b_try_check_boolean_expression_c2(Pred,LocalState,InState,WF,pred_true) :-
3629		%hit_profiler:add_profile_hit(b_try_check_failed(Pred),3),
3630		b_test_inner_boolean_expression(Pred,LocalState,InState,WF).
3631		b_try_check_boolean_expression_c2(Pred,LocalState,InState,WF,pred_false) :-
3632		b_not_test_inner_boolean_expression(Pred,LocalState,InState,WF).
3633
3634
3635		% WHILE SUBSTITUTION TREATMENT:
3636
3637		:- if(environ(prob_noopt_mode,true)).
3638		get_while_reads_write_info_and_filter_state(Info,LocalState,InState,LS,IS,ModVars) :-
3639		member(modifies(ModVars),Info),!,
3640		LS=LocalState, IS=InState. % do not filter state
3641		:- endif.
3642		get_while_reads_write_info_and_filter_state(Info,LocalState,InState,LS,IS,ModVars) :-
3643		member(reads(ReadVars),Info),
3644	?	member(modifies(ModVars),Info),!,
3645		% we may go around the loop many times: avoid carrying around unused variables
3646		ord_union(ReadVars,ModVars,ReadOrModVars),
3647		filter_states(ReadOrModVars,LocalState,InState,LS,IS).
3648		get_while_reads_write_info_and_filter_state(Info,LocalState,InState,LS,IS,ModVars) :-
3649		add_internal_error('No reads & modifies info for while loop: ',get_while_reads_write_info_and_filter_state(Info,LocalState,InState,LS,IS,ModVars)),
3650		ModVars=_, % all variables assumed to be modified
3651		LS=LocalState, IS=InState.
3652
3653		unused_variable(List,bind(Var,_)) :-
3654		% b_is_variable(Var), % TO DO: also include constants in reads Info ?
3655		ord_nonmember(Var,List).
3656		unused_localvariable(List,bind(Var,Val)) :- ord_nonmember(Var,List),
3657		(nonvar(Val),Val=(_,_) -> atom_codes(Var,Codes), Codes \= [64|_] % not a lazy_let ID starting with @
3658		% 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 ?
3659		; true).
3660
3661		filter_states(ReadOrModVars,LocalState,InState,LS,IS) :-
3662		exclude(unused_localvariable(ReadOrModVars),LocalState,LS),
3663		exclude(unused_variable(ReadOrModVars),InState,IS).
3664		% TO DO: investigate whether we should use ord_intersect; ReadVars is already sorted
3665
3666		:- block lazy_exclude(-,?,?).
3667		lazy_exclude([],_,[]).
3668		lazy_exclude([bind(Var,Val)|T],ModVars,Res) :- lazy_exclude_aux(Var,Val,T,ModVars,Res).
3669		:- block lazy_exclude_aux(-,?,?,?,?).
3670		lazy_exclude_aux(Var,Val,T,ModVars,Res) :-
3671	?	(member(Var,ModVars) -> Res = [bind(Var,Val)|RT]
3672		; Res = RT),
3673		lazy_exclude(T,ModVars,RT).
3674
3675
3676		:- use_module(kernel_tools,[ground_state_check/2]).
3677		% outermost while code:; at next iteration b_execute_while1 will be called.
3678		:- block b_execute_while(?,?,?,?,?,-, ?,?,?, ?,?). % we block on Variant Value int(VarVal)
3679		b_execute_while(COND,STMT,INV,VARIANT,ModVars,int(VarVal),LocalState,InState,OutState,WF,BodyPath) :-
3680		%kernel_waitflags:get_idle_wait_flag(b_execute_while,WF,LWF),
3681		(number(VarVal),VarVal =< 50
3682		-> LWF=VarVal % we will wait anyway on GrInState below; no danger for WD issues in in b_optimize
3683		; no_pending_waitflags(WF) -> get_wait_flag0(WF,LWF) %important for e.g. PerformanceTests/While/LiftExec_LIM.mch
3684		; 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?
3685		% see also tests 979, 981
3686		),
3687		% before entering while loop, we wait for co-routines to complete that may have activated b_execute_while
3688		b_execute_while_idle(COND,STMT,INV,VARIANT,ModVars,int(VarVal),LocalState,InState,OutState,WF,LWF,BodyPath).
3689
3690		:- block b_execute_while_idle(?,?,?,?,?,?, ?,?,?, ?,-,?). % we block on enumeration starting wait_flag
3691		b_execute_while_idle(COND,STMT,INV,VARIANT,ModVars,int(VarVal),LocalState,InState,OutState,WF,_,BodyPath) :-
3692		%ground_constraintprop_wait_flags(WF),
3693		(number(VarVal), VarVal>50, preference(compile_while_body,true)
3694		% if VarVal > 50 -> worthwhile to compile STMT
3695		% TO DO: also take size of body into account, and what if only a small part of the body is reachable in each iteration
3696	?	-> b_compiler:b_optimize(STMT,ModVars,LocalState,InState,CSTMT,WF),
3697		% print(compiled_while(ModVars)),nl, translate:print_subst(CSTMT),nl,
3698		OutState=WhileOutState,
3699		exclude(unused_variable(ModVars),LocalState,LS), % only keep modified vars; all other compiled
3700		exclude(unused_variable(ModVars),InState,IS) % only keep modified vars; all other compiled
3701		; CSTMT=STMT, LS=LocalState, IS=InState,
3702		lazy_exclude(WhileOutState,ModVars,OutState) % only copy over those variables (potentially) modified by While loop
3703		% Note: it is important that we only have one copy of each modified variable in OutState
3704		),
3705		ground_state_check(InState,GrInState),
3706	?	b_execute_while_loop_block(GrInState,COND,CSTMT,INV,VARIANT,none,VarVal,LS,IS,WhileOutState,WF,BodyPath).
3707
3708		:- block b_execute_while_loop_block(-,?,?,?,?,?,?,?,?,?,?,?).
3709		b_execute_while_loop_block(_,COND,CSTMT,INV,VARIANT,none,VarVal,LS,IS,WhileOutState,WF,BodyPath) :-
3710		% the information passed to the outside is the number of iterations
3711	?	b_execute_while_loop(COND,CSTMT,INV,VARIANT,none,VarVal,LS,IS,WhileOutState,WF,while_bpath(0,none),BodyPath).
3712
3713		:- block b_execute_while1(?,?,?,?,?,-,?,?,?,?,?,?).
3714		b_execute_while1(COND,STMT,INV,VARIANT,PrevVariantValue,int(VarVal),LocalState,InState,OutState,WF,InPath,OutPath) :-
3715		% get_last_wait_flag(while(VarVal),WF,LWF),
3716		deref_wf(WF,FreshWF),
3717		%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
3718		% this can lead to enumeration warnings; the same applies to other calls to ground_constraintprop_wait_flags below
3719		b_execute_while_loop(COND,STMT,INV,VARIANT,PrevVariantValue,VarVal,LocalState,InState,OutState,FreshWF,InPath,OutPath).
3720
3721		% block on PrevVarVal and VarVal not yet needed here; but we need it for b_execute_while_body below
3722		:- block b_execute_while_loop(?,?,?,?,-,?,?,?,?,?,?,?), b_execute_while_loop(?,?,?,?,?,-,?,?,?,?,?,?).
3723		b_execute_while_loop(COND,STMT,INV,VARIANT,PrevVarVal,VarVal,LocalState,InState,OutState,WF,InPath,OutPath) :-
3724	?	b_try_check_boolean_expression_c(INV,LocalState,InState,WF,INVRes),
3725		%ground_constraintprop_wait_flags(WF), % seems to slow down interpretation
3726	?	b_check_execute_while_loop1(INVRes,COND,STMT,INV,VARIANT,PrevVarVal,VarVal,LocalState,InState,OutState,WF,InPath,OutPath).
3727
3728		:- block b_check_execute_while_loop1(-,?,?,?,?,?,?,?,?,?,?, ?,?).
3729		b_check_execute_while_loop1(pred_false,_COND,_STMT,INV,_VAR,_PrevVarVal,VarVal,LocalState,InState,_OutState,WF,P,P) :-
3730		add_abort_error_span(while_invariant_violation,
3731		'While INVARIANT VIOLATED, current VARIANT value: ',VarVal,span_predicate(INV,LocalState,InState),WF).
3732		b_check_execute_while_loop1(pred_true,COND,STMT,INV,VARIANT,PrevVarVal,VarVal,LocalState,InState,OutState,WF,InPath,OutPath) :-
3733		b_try_check_boolean_expression_c(COND,LocalState,InState,WF,CondRes),
3734		%ground_constraintprop_wait_flags(WF), % seems to slow down interpretation
3735	?	b_check_execute_while_loop2(CondRes,COND,STMT,INV,VARIANT,PrevVarVal,VarVal,LocalState,InState,OutState,WF,InPath,OutPath).
3736
3737		:- block b_check_execute_while_loop2(-,?,?,?,?,?,?,?,?,?,?, ?,?).
3738		b_check_execute_while_loop2(pred_false,_COND,_STMT,_INV,_VARIANT,_PrevVarVal,_VarVal,_LS,InState,OutState,_WF,P,P) :-
3739		OutState=InState. % we copy over the while InState: the updates will be computed at the end of the while loop
3740		b_check_execute_while_loop2(pred_true,COND,STMT,INV,VARIANT,PrevVarVal,VarVal,LocalState,InState,OutState,WF,InPath,OutPath) :-
3741
3742		%hit_profiler:add_profile_hit(b_execute_while_body(STMT,VarVal,PrevVarVal,LocalState),2),
3743		% TO DO: maybe only compute VARIANT now and not above ??
3744		% b_compute_expression(VARIANT,LocalState,InState,VarVal,WF),
3745		% ground_constraintprop_wait_flags(WF), %% moved here because VARIANT computed later
3746		inc_while_path(InPath,P1),
3747	?	b_execute_while_body(COND,STMT,INV,VARIANT,PrevVarVal,VarVal,LocalState,InState,OutState,WF,P1,OutPath).
3748
3749		% register in the event path that we have entered one more while iteration:
3750		inc_while_path(while_bpath(Cnt,LastIterPath),while_bpath(C1,LastIterPath)) :- C1 is Cnt+1.
3751		add_while_body_path(while_bpath(Cnt,_),Path1,Res) :-
3752		get_preference(eventtrace,true),!,
3753		Res = while_bpath(Cnt,Path1). % TODO: we could given a setting construct a sequence
3754		add_while_body_path(P,_,P).
3755
3756		%:- block b_execute_while_body(?,?,?,?,-,?,?,?,?,?,?,?), b_execute_while_body(?,?,?,?,?,-,?,?,?,?,?,?).
3757		% we must ensure VarVal and PrevVaraintValue known
3758		% the block declaration above for b_execute_while_loop already ensures this
3759		b_execute_while_body(_COND,_STMT,_INVARIANT,VAR,_PV,VarVal,LocalState,InState,_OutState,WF,Path,Path) :-
3760		VarVal<0, !, % more efficient than is_not_natural(int(VarVal)),
3761		%ground_constraintprop_wait_flags(WF),
3762		% add_abort_error_span will fail; hence no need to set _OutState
3763		add_abort_error_span(while_variant_error,'While VARIANT not NATURAL:',VarVal,span_predicate(VAR,LocalState,InState),WF).
3764		b_execute_while_body(_COND,_STMT,_INVARIANT,VAR,PrevVariantValue,VarVal,LocalState,InState,_OutState,WF,Path,Path) :-
3765		% check no longer required VarVal>=0,%is_natural(int(VarVal),WF),
3766		PrevVariantValue \= none,
3767		PrevVariantValue =< VarVal, !, %less_than_equal(int(PrevVariantValue),int(VarVal)),
3768		%ground_constraintprop_wait_flags(WF),
3769		% add_abort_error_span will fail; hence no need to set _OutState
3770		ajoin(['VARIANT = ',VarVal,', previous value = ',PrevVariantValue],Details),
3771		add_abort_error_span(while_variant_error,'While VARIANT not decreasing:',
3772		Details,span_predicate(VAR,LocalState,InState),WF).
3773		b_execute_while_body(COND,STMT,INV,VARIANT,_PrevVariantValue,VarVal,LocalState,InState,OutState,WF,InPath,OutPath) :-
3774		% check no longer required due to cuts above %VarVal>=0, %is_natural(int(VarVal),WF),
3775		%(PrevVariantValue==none -> true ; less_than(int(VarVal),int(PrevVariantValue))),
3776		%ground_constraintprop_wait_flags(WF), % seems to slow down interpretation
3777		copy_wf_start(WF,while_body,CWF),
3778	?	b_execute_statement(STMT,LocalState,InState,LHSUpdates,CWF,Path1,output_required),
3779		add_while_body_path(InPath,Path1,P1),
3780		copy_wf_finish(WF,CWF),
3781		ground_det_wait_flag(WF), % TODO: remove this
3782		store_intermediate_updates_wf(InState,LHSUpdates,IntermediateState,STMT,WF),
3783		check_state_skeleton_bound(LHSUpdates,Bound), % otherwise variable lookups will cause problems; ensures IntermediateState skeleton bound
3784		b_execute_while_when_state_set(COND,STMT,INV,VARIANT,VarVal,LocalState,IntermediateState,OutState,WF,Bound,P1,OutPath).
3785
3786		:- block b_execute_while_when_state_set(?,?,?,?,?,?,?,?,?,-,?,?).
3787		b_execute_while_when_state_set(COND,STMT,INV,VARIANT,PrevVariantValue,LocalState,State,Res,WF,_,InPath,OutPath) :-
3788		copy_wf_start(WF,while2,CWF),
3789		b_compute_expression(VARIANT,LocalState,State,VarVal,CWF),
3790		copy_wf_finish(WF,CWF),
3791		b_execute_while1(COND,STMT,INV,VARIANT,PrevVariantValue,VarVal,LocalState,State,Res,WF,InPath,OutPath).
3792
3793		% ------------- IF-THEN-ELSE
3794
3795		:- block b_execute_else_list2(-,?,?,?, ?,?,?,?,?,-,?). % should we also unblock if LWF set ? needed for seq. composition to set up state ??
3796		b_execute_else_list2(PredRes,Body,Rest,LocalState,InState,OutState,InnerWF,CaseNr,Path,LWF,OR) :-
3797		%(var(PredRes) -> print('IF-THEN-ELSE ENUMERATION: '), translate:print_subst(Body),nl ; true),
3798	?	b_execute_else_list3(PredRes,Body,Rest,LocalState,InState,OutState,InnerWF,CaseNr,Path,LWF,OR).
3799
3800		b_execute_else_list3(pred_true,Body,_,LocalState,InState,OutState,WF,CaseNr,if(CaseNr,Path),_,OR) :-
3801	?	push_wait_flag_call_stack_info(WF,b_subst_call(if_then_body,Body),WF2),
3802	?	b_execute_statement(Body,LocalState,InState,OutState,WF2,Path,OR).
3803		b_execute_else_list3(pred_false,_Body,Rest,LocalState,InState,OutState,WF,CaseNr,Path,LWF,OR) :-
3804		CaseNr1 is CaseNr+1,
3805	?	b_execute_else_list(Rest,LocalState,InState,OutState,WF,CaseNr1,Path,LWF,OR).
3806
3807		b_execute_else_list([],_,_State,[],_WF,_,if_skip,_LWF,_OR). /* skip */
3808		b_execute_else_list([TExpr|Rest],LocalState,InState,OutState,WF,CaseNr,Path,LWF,OR) :-
3809		get_texpr_expr(TExpr,if_elsif(Test,Body)), % Info field not used
3810		% get_enumeration_finished_wait_flag(WF,LWF),
3811		InnerWF=WF, %clone_wait_flags_from1(WF,InnerWF),
3812		push_wait_flag_call_stack_info(InnerWF,b_expr_call(if_elsif_test,Test),WF2),
3813	?	b_try_check_boolean_expression_lwf(Test,LocalState,InState,WF2,'$ENUMERATION',PredRes,LWF),
3814		%ground_wait_flag0(InnerWF),
3815		(nonvar(PredRes)
3816	?	-> b_execute_else_list3(PredRes,Body,Rest,LocalState,InState,OutState,InnerWF,CaseNr,Path,LWF,OR)
3817		; (LWF == '$GENERATE_ON_DEMAND' ->
3818		get_wait_flag0(WF,LWF1),
3819		get_wait_flag_if_necessary(PredRes,LWF1,OR,WF,LWF2)
3820		; LWF2=LWF),
3821	?	b_execute_else_list2(PredRes,Body,Rest,LocalState,InState,OutState,InnerWF,CaseNr,Path,LWF2,OR)
3822		).
3823
3824		% avoid calling get_wait_flag if possible (expensive)
3825		:- block get_wait_flag_if_necessary(-,-,?,?,?).
3826		get_wait_flag_if_necessary(PredRes,_,OR,WF,LWF2) :- var(PredRes), !, % we need waitflag
3827		(preferences:preference(use_smt_mode,true) -> Prio = 2 % was 2.0
3828		; OR == output_required -> Prio = 2000
3829		; Prio = 200000 %last_finite_priority(Prio)
3830		), % TO DO: check if there is a guard inside; if not we can wait much longer; unless we are in CBC mode
3831		get_wait_flag(Prio,if_else,WF,LWF2).
3832		get_wait_flag_if_necessary(_,_,_,_,_).
3833
3834		:- block b_execute_choice(?,?,?,?,?,?,-,?).
3835		b_execute_choice(ChoiceList,LocalState,InState,OutState,WF,choice(Nr,Path),_WFC,OR) :-
3836	?	nth1(Nr,ChoiceList,Choice),
3837		b_execute_statement(Choice,LocalState,InState,OutState,WF,Path,OR).
3838
3839		% execute ASSERT PreCond THEN Body
3840		b_execute_assertion(_PreCond,Body,LocalState,InState,OutState,WF,Path,OR) :-
3841		preference(do_assert_checking,false), % ASSERT checking disabled
3842		!,
3843		b_execute_statement(Body,LocalState,InState,OutState,WF,Path,OR).
3844		b_execute_assertion(PreCond,Body,LocalState,InState,OutState,WF,Path,OR) :-
3845	?	b_try_check_boolean_expression_lwf(PreCond,LocalState,InState,WF,'$ENUMERATION',PredRes,WFC),
3846		% enumeration of PredRes before WFE set make sense, Body can instantiate values
3847		(var(PredRes) -> get_last_wait_flag(assertion,WF,WFC) ; true),
3848		b_execute_assertion_block(PredRes,PreCond,Body,LocalState,InState,OutState,WF,Path,OR).
3849
3850		:- block b_execute_assertion_block(-, ?,?,?,?, ?,?,?,?).
3851		b_execute_assertion_block(pred_true,_PreCond,Body,LocalState,InState,OutState,WF,Path,OR) :-
3852		Path = assertion(IPath),
3853		b_execute_statement(Body,LocalState,InState,OutState,WF,IPath,OR).
3854		b_execute_assertion_block(pred_false,PreCond,_Body,LocalState,InState,_OutState,WF,Path,_OR) :-
3855		Path = assertion_violated,
3856		translate_bexpression(PreCond,PreString),
3857		add_abort_error_span(assert_error,'ASSERT violated: ',PreString,span_predicate(PreCond,LocalState,InState),WF).
3858
3859		:- block check_state_skeleton_bound(-,?).
3860		check_state_skeleton_bound([],true).
3861		check_state_skeleton_bound([bind(Var,_)|T],Res) :-
3862		check_state_skeleton_bound_aux(Var,T,Res).
3863
3864		:- block check_state_skeleton_bound_aux(-,?,?).
3865		check_state_skeleton_bound_aux(Var,T,Res) :-
3866		(atomic(Var) -> true ; print('*** variable name not atomic: '), print(Var),nl),
3867		check_state_skeleton_bound(T,Res).
3868
3869
3870		b_execute_statement_list_when_state_set(StmtList,LS,State,USoFar,Res,WF,Path,OR) :-
3871		check_state_skeleton_bound(State,Bound), % otherwise variable lookups will cause problems
3872	?	b_execute_statement_when_state_set2(StmtList,LS,State,USoFar,Res,WF,Path,Bound,OR).
3873		:- block b_execute_statement_when_state_set2(?,?,?,?,?,?,?,-,?).
3874		b_execute_statement_when_state_set2(StmtList,LS,State,UpdatesSofar,Res,WF,Path,_,OR) :-
3875		(get_preference(warn_about_failing_assignments,true)
3876		; get_preference(provide_trace_information,true)),!,
3877		copy_wf_start(WF,while2,CWF),
3878	?	if(b_execute_sequence(StmtList,LS,State,StmtUpdates,CWF,Path,OR),
3879		true,
3880		(StmtList=[NS|_], % typically, statements inside a sequential composion do not have inner guards
3881		(get_preference(warn_about_failing_assignments,true)
3882		-> add_warning_wf(b_interpreter,'Statement inside sequential composition fails: ',NS,NS,WF)
3883		; add_message_wf(b_interpreter,'Statement inside sequential composition fails: ',NS,NS,WF)
3884		),
3885		fail)),
3886	?	copy_wf_finish(WF,CWF),
3887	?	merge_updates(UpdatesSofar,StmtUpdates,Res).
3888		b_execute_statement_when_state_set2(StmtList,LS,State,UpdatesSofar,Res,WF,Path,_,OR) :-
3889		copy_wf_start(WF,while2,CWF),
3890	?	b_execute_sequence(StmtList,LS,State,StmtUpdates,CWF,Path,OR),
3891	?	copy_wf_finish(WF,CWF),
3892		merge_updates(UpdatesSofar,StmtUpdates,Res).
3893
3894
3895		store_values([], [], []).
3896		store_values([IDsHd|IDsTl], [VALsHd|VALsTl], [bind(IDsHd,VALsHd)|OutStateTl]) :-
3897		store_values(IDsTl, VALsTl, OutStateTl).
3898
3899
3900
3901
3902		/* the B syntax does allow multiple definitions in a LET: */
3903
3904		b_execute_let_definitions(Pred,LocalState,State,WF) :-
3905		is_a_conjunct(Pred,LHS,RHS),!,
3906		b_execute_let_definitions(LHS,LocalState,State,WF),
3907		b_execute_let_definitions(RHS,LocalState,State,WF).
3908		b_execute_let_definitions(b(equal(LHS,RHS),_,_),LocalState,State,WF) :- !,
3909		b_compute_expression(LHS,LocalState,State,LHSVal,WF),
3910		b_compute_expression(RHS,LocalState,State,RHSVal,WF),
3911		% TO DO: ideally we should check if LHS is a declared identifier and is only defined once
3912		kernel_objects:equal_object_optimized(LHSVal,RHSVal,b_execute_let_definitions).
3913		b_execute_let_definitions(b(lazy_let_pred(Id,AssignmentExpr,Body),_,_),LocalState,State,WF) :- !,
3914		add_lazy_let_id_and_expression(Id,AssignmentExpr,LocalState,State,NewLocalState,WF),
3915		b_execute_let_definitions(Body,NewLocalState,State,WF).
3916		b_execute_let_definitions(P,_L,_S,WF) :-
3917		add_internal_error_wf(b_interpreter,'Let contains a predicate which is not an equality: ',P,P,WF),fail.
3918
3919
3920		/* -----------------------------------------*/
3921		/* b_assign_function */
3922		/* -----------------------------------------*/
3923
3924		b_assign_values_or_functions([],[],_LS,_S,[],_WF,_OR).
3925		b_assign_values_or_functions([TExpr|ERest],[Value|VRest],LS,S,[bind(Id,New)|NRest],WF,OR) :-
3926		get_texpr_expr(TExpr,Expr),
3927	?	b_assign_value_or_function(Expr,Value,LS,S,Id,New,WF,OR),
3928		b_assign_values_or_functions(ERest,VRest,LS,S,NRest,WF,OR).
3929
3930		:- use_module(kernel_tools,[ground_value_check/2]).
3931		:- use_module(kernel_records,[overwrite_record_wf/5]).
3932		b_assign_value_or_function(identifier(Id),Value,_LS,_S,LHS_Id,FullValue,WF,_OR) :- !,
3933		LHS_Id=Id,
3934	?	equal_object_wf(FullValue,Value,b_assign_value_or_function(Id),WF).
3935		b_assign_value_or_function(function(Fun,Arg),Value,LocalState,InState,Id,FullValue,WF,OR) :- !,
3936		%b_compute_expression(Arg,LocalState,InState,ArgVal,WF),
3937		%expand_global_sets_but_not_closures(ArgVal,EArgVal),
3938		FunMNF = eval_must_not_fail('Assignment left-hand-side (or part thereof) could not be evaluated: ',Fun), % could be f(..)(..)
3939		b_compute_assign_expressions_when([Arg,FunMNF],LocalState,InState,[ArgVal,FunVal],WF,OR), % or should we pass the OR info around ?
3940		/* we do not examine local state: these vars cannot be modified by operations !? */
3941		(OR=output_required -> override(FunVal,ArgVal,Value,NewFun,WF)
3942		; ground_value_check((FunVal,ArgVal,Value),GRV),
3943		% wait until all arguments known so that we can effiently compute override
3944		blocking_override(GRV,FunVal,ArgVal,Value,NewFun,WF)),
3945		get_texpr_expr(Fun,Lhs),
3946		b_assign_value_or_function(Lhs,NewFun,LocalState,InState,Id,FullValue,WF,OR).
3947		b_assign_value_or_function(record_field(RecordExpr,FieldName),Value,LocalState,InState,LHS_Id,FullValue,WF,OR) :-
3948		!,
3949		% we allow nested record assignments: x'Field1'Field2 := Value
3950		b_compute_expression(RecordExpr,LocalState,InState,OldRecVal,WF),
3951		overwrite_record_wf(OldRecVal,FieldName,Value,NewRecVal,WF),
3952		get_texpr_expr(RecordExpr,Lhs),
3953		b_assign_value_or_function(Lhs,NewRecVal,LocalState,InState,LHS_Id,FullValue,WF,OR).
3954		b_assign_value_or_function(LHS,_Value,_LS,_InState,_Id,_FullValue,WF,_OR) :-
3955		add_internal_error_wf(b_interpreter,'Illegal LHS for assignment (must be ID(.) or ID\'Field or ID): ',LHS,LHS,WF),
3956		fail.
3957
3958		:- block blocking_override(-,?,?,?,?,?).
3959		blocking_override(_,FunVal,ArgVal,Value,NewFun,WF) :- override(FunVal,ArgVal,Value,NewFun,WF).
3960
3961
3962		/* -----------------------------------------*/
3963		/* b_execute_statements_in_parallel */
3964		/* -----------------------------------------*/
3965		/* execute a parallel composition of statements */
3966		:- assert_pre(b_interpreter:b_execute_statements_in_parallel(Ss,LS,State,_Os,WF,_Paths,_OR),
3967		(ground_check(Ss),type_check(LS,store),
3968		type_check(State,store),type_check(WF,wait_flag))).
3969		:- assert_post(b_interpreter:b_execute_statements_in_parallel(_Ss,_LS,_State,Os,WF,_Paths,_OR),
3970		(type_check(Os,store),type_check(WF,wait_flag))).
3971
3972		b_execute_statements_in_parallel([],_,_,[],_WF,[],_OR).
3973		b_execute_statements_in_parallel([Stmt|TS],LocalState,InState,OutState,WF,[Path1|TPath],OR) :-
3974	?	b_execute_statement(Stmt,LocalState,InState,OutState1,WF,Path1,OR),
3975	?	combine_updates(OutState1,OutState2,OutState), /* merge updates */
3976	?	b_execute_statements_in_parallel(TS,LocalState,InState,OutState2,WF,TPath,OR).
3977
3978
3979		%:- block combine_updates(-,-,?).
3980		%combine_updates(A,B,C) :- (B==[] -> A=C ; combine_updates_aux(A,B,C)).
3981
3982		% TO DO: investigate whether we could also unblock on second argument and copy it to result
3983		:- block combine_updates(-,?,?). % can also be used to merge states
3984		combine_updates([],X,R) :- !,R=X.
3985	?	combine_updates([H|T],Y,Res) :- !, Res=[H|Z], combine_updates(T,Y,Z).
3986		combine_updates(X,Y,Z) :- add_internal_error('Illegal call: ',combine_updates(X,Y,Z)),fail.
3987
3988
3989
3990		b_execute_initialisation_statement(Stmt,LS,In,Out,_OUTERWF,Path,OR) :-
3991		init_wait_flags(WF,[b_execute_initialisation_statement]),
3992		% each initialisation can be executed in isolation (except in CBC mode)
3993	?	b_execute_statement(Stmt,LS,In,Out,WF,Path,OR),
3994	?	ground_wait_flags(WF).
3995
3996		% replace certain parallels by init_parallel for better error reporting in INITIALISATION
3997		% will not be used in CBC mode (by set_up_initialisation or tc_initialise)
3998		translate_init_statements(b(Stmt,subst,I),b(TStmt,subst,I)) :-
3999		tp2(Stmt,I,TStmt).
4000		tp2(assign(LHS,RHS),I,parallel(S)) :- LHS=[_,_|_],
4001		% translate multiple assignment into parallel assignments
4002		maplist(generate_assignment(I),LHS,RHS,S),
4003		!.
4004		tp2(Stmt,I,init_statement(b(Stmt,subst,I))) :- %get_preference(provide_trace_information,true),
4005		wrap_stmt(Stmt),
4006		!.
4007		% TO DO: cover WHILE
4008		tp2(parallel(S),_,parallel(TS)) :- maplist(translate_init_statements,S,TS),
4009		!.
4010		tp2(sequence(A),_,sequence(LA)) :- !,maplist(translate_init_statements,A,LA).
4011		tp2(if(A),_,if(LA)) :- !, maplist(translate_init_statements,A,LA).
4012		tp2(if_elsif(Test,Body),_,if_elsif(Test,LBody)) :- !,
4013		translate_init_statements(Body,LBody).
4014		tp2(X,_,X). % :- functor(X,F,A), nl,nl,print(uncovered(F/A)),nl,nl.
4015
4016		wrap_stmt(assign(_,_)).
4017		wrap_stmt(becomes_element_of(_,_)).
4018		wrap_stmt(becomes_such(_,_)).
4019		wrap_stmt(assign_single_id(_,_)).
4020
4021		generate_assignment(I,V,RHS,b(init_statement(b(Assign,subst,I)),subst,I)) :-
4022		Assign = assign([V],[RHS]).
4023
4024
4025
4026		/* ---------------------------------------*/
4027		/* b_execute_top_level_statement */
4028		/* ---------------------------------------*/
4029
4030		/* this is just like b_execute_statement with the
4031		only difference that a PRE-condition is treated like
4032		a select, i.e., it does not generate an abort if used
4033		outside of its condition */
4034		b_execute_top_level_statement(TExpr,LocalState,InState,OutState,WF,Path,OR) :-
4035		get_texpr_expr(TExpr,Stmt),
4036	?	b_execute_top_level_statement2(Stmt,TExpr,LocalState,InState,OutState,WF,Path,OR).
4037		b_execute_top_level_statement2(precondition(PreCond,Body),TExpr,
4038		LocalState,InState,OutState,WF,Path,OR) :-
4039		preferences:preference(treat_outermost_pre_as_select,true),!,
4040		%debug_println(9,'Top level PRE treated as SELECT'),
4041		preference(ltsmin_do_not_evaluate_top_level_guards,NO_EVAL),
4042		(NO_EVAL=true, % do not evaluate guards detected by guard splitting
4043		get_texpr_info(TExpr,Info),member(prob_annotation('LTSMIN-GUARD'),Info)
4044		-> debug_println(9,ltsmin_guard_will_not_be_evaluated)
4045	?	; b_test_boolean_expression(PreCond,LocalState,InState,WF)
4046		),
4047		% b_tracetest_boolean_expression(PreCond,LocalState,InState,WF,one), % comment in for debugging
4048	?	b_execute_statement(Body,LocalState,InState,OutState,WF,Path,OR).
4049		b_execute_top_level_statement2(lazy_let_subst(Id,IdExpr,Body),_,
4050		LocalState,InState,OutState,WF,lazy_let(Path),OR) :-
4051		!,
4052		add_lazy_let_id_and_expression(Id,IdExpr,LocalState,InState,NewLocalState,WF),
4053	?	b_execute_top_level_statement(Body,NewLocalState,InState,OutState,WF,Path,OR).
4054		b_execute_top_level_statement2(_,TExpr,LocalState,InState,OutState,WF,Path,OR) :-
4055	?	b_execute_statement(TExpr,LocalState,InState,OutState,WF,Path,OR).
4056
4057
4058		/* -----------------------------*/
4059		/* b_execute_operation */
4060		/* -----------------------------*/
4061		/* execute a single operation */
4062
4063		try_get_op_name(FullOperation,_Name) :- var(FullOperation),!.
4064		try_get_op_name('-->'(FO,_),Name) :- !,try_get_op_name(FO,Name).
4065		try_get_op_name(FullOperation,Name) :- functor(FullOperation,Name,_).
4066
4067
4068
4069		:- assert_pre(b_interpreter:b_execute_top_level_operation_update(_Name,_FullOperation,InState,_NewState,_P),
4070		(ground_check(InState),type_check(InState,store))).
4071		:- assert_post(b_interpreter:b_execute_top_level_operation_update(Name,_FullOperation,_InState,NewState,_Path),
4072		(type_check(NewState,store),ground_check(Name))).
4073
4074
4075		b_execute_top_level_operation_update(Name,FullOperation,InState,Updates,Path) :-
4076	?	b_execute_top_level_operation_update_wf(Name,FullOperation,InState,Updates,Path,WF),
4077	?	ground_wait_flags(WF).
4078		%store:store_updates_and_normalise(Updates,InState,NewState).
4079
4080
4081		b_execute_top_level_operation_update_wf(Name,FullOperation,InState,Updates,Path,WF) :-
4082		init_wait_flags(WF,[]), % now treated by call_stack: [expansion_context(op(Name),[])]),
4083		% b_execute_operation2 below will push_wait_flag_call_stack_info
4084		try_get_op_name(FullOperation,Name), b_top_level_operation(Name),
4085		setup_result_input_values(Name,RIV),
4086		Info=unknown, % Info extracted later for top_level
4087	?	b_execute_operation2(Name,FullOperation,InState,Updates,_,RIV,_,true,Path,Info,WF,output_not_required).
4088
4089		% set up value of read output variables *before* operation call to some dummy value
4090		setup_result_input_values(Name,ResultInputValues) :-
4091		(get_preference(allow_operations_to_read_outputs,true),
4092		b_operation_reads_output_variables(Name,_Reads,TReadsInfo) ->
4093		maplist(setup_read_output_variable,TReadsInfo,ResultInputValues)
4094		%translate_bstate_limited(ResultInputValues,TS),
4095		%ajoin(['Warning: setting read output variables in ',Name,' to default values: ',TS],Msg),
4096		%add_warning(b_interpreter,Msg),
4097		%store_error_for_context_state(eventerror(Name,event_other_error(Msg),[]),_Id)
4098		; ResultInputValues=[]).
4099
4100		:- use_module(typing_tools,[any_value_for_type/2]).
4101		setup_read_output_variable(reads_result(_,Name,Type),bind(Name,Val)) :- any_value_for_type(Type,Val).
4102
4103		% for use by CBC:
4104		b_execute_top_level_operation_wf(Name,FullOperation,ParaVals,ResultVals,InState,NewState,Path,WF) :-
4105		try_get_op_name(FullOperation,Name),
4106		if(b_top_level_operation(Name),true,
4107		(add_internal_error('Unknown operation name for b_execute_top_level_operation_wf: ',Name),fail)
4108		),
4109		% call before execute operation to copy over results immediately in case b_execute_operation2 generates choice points:
4110		store_intermediate_updates_wf(InState,Updates,NewState,operation(Name),WF), % no normalising is better for constraint propagation
4111		% TO DO?: copy over unmodified variables b_get_machine_variables(Variables),copy_unmodified_variables(Variables,OpName,InState,NewState)
4112		setup_result_input_values(Name,RIV),
4113		Info=unknown, % Info extracted later for top_level
4114		b_execute_operation2(Name,FullOperation,InState,Updates,ParaVals,RIV,ResultVals,true,Path,Info,WF,output_required).
4115		% we should ensure that Operation part is executed to instantiate NewOutState skeleton
4116
4117
4118
4119		% Note : if the argument OR (OutputRequired) has value output_required this indicates that the output
4120		% an operation or its effect is required (e.g., because of sequential composition) and the constraint solver
4121		% should not delay computing the effect of the operation
4122		% Atelier-B Handbook 6.16: [R <- op (E)]P = [X := E ; S ; R :=Y] P where op defined by X <- op(Y) = S
4123		b_execute_operation_with_parameters(Name,LocalState,InState,Results,Parameters,OutState,ParamValues,ResultValues,
4124		Path,Info,WF,OR) :-
4125		(b_is_operation_name(Name)
4126		-> b_compute_expressions(Parameters,LocalState,InState,ParamValues,WF),
4127		% TO DO : remove local vars from InState
4128		(b_operation_reads_output_variables(Name,_Reads,TReadsInfo)
4129		-> % format('Transferring outputs ~w ~w~n ~w~n',[Name,_Reads,TReadsInfo]),
4130		maplist(output_parameters_value(LocalState,InState,Results,Info,WF),TReadsInfo,ResultInputValues)
4131		; ResultInputValues=[]),
4132	?	call_b_execute_operation2(Name,InState,OutState,ParamValues,ResultInputValues,ResultValues,false,
4133		Path,Info,WF,OR)
4134		; add_internal_error('Unknown B operation, cannot call: ',
4135		b_execute_operation_with_parameters(Name,LocalState,InState,Results,Parameters,
4136		OutState,ParamValues,ResultValues,Path,Info,WF,OR)),
4137		fail
4138		).
4139
4140
4141		%b_execute_operation_in_expression(Name,_LocalState,_InState,_Parameters,_Value,Info,_WF) :-
4142		% % This clause is disabled: sometimes variables are marked as read even though they are not:
4143		% % the analysis is not precise due to sequential composition, CASE statements, ...
4144		% b_operation_reads_output_variables(Name,_Reads,_TReadsInfo),!,
4145		% add_error(b_interpreter,'Operation that reads output cannot be called in expression: ',Name,Info),
4146		% fail.
4147		b_execute_operation_in_expression(Name,LocalState,InState,Parameters,Value,Info,WF) :-
4148		% TODO: check that this is a query operation; probably done in type checker
4149		OR=output_required, % alternative: OR=output_not_required,
4150		setup_result_input_values(Name,ResultInputValues),
4151		b_compute_expressions(Parameters,LocalState,InState,ParamValues,WF),
4152		(b_get_operation_normalized_read_write_info(Name,Read,_Modified)
4153		-> true % Modified should be []
4154		; member(reads(Read),Info)
4155		-> add_message(b_interpeter,'Unregistered operation in expression: ',Name) % prefixed operation not found
4156		; add_error(b_interpeter,'Cannot obtain read-write info for operation in expression:',Name),
4157		Read=[]
4158		),
4159		create_inner_wait_flags(WF,operation_call_in_expr,OpWF),
4160		ground_value_check(ParamValues,ParaGround),
4161		exclude(unused_variable(Read),InState,IS),
4162		ground_state_check(IS,StateGround),
4163		% TO DO: in case of recursion it may be good to delay executing sub-operation until some WF is set
4164		call_b_execute_operation2(Name,IS,_OutState,ParamValues,ResultInputValues,ResultValues,false,_Path,Info,OpWF,OR),
4165		ground_inner_wf(ParaGround,StateGround,OpWF),
4166		make_couplise(ResultValues,Value).
4167
4168		% ground inner waitflags when parameters and relevant read variables fully known
4169		:- block ground_inner_wf(-,?,?), ground_inner_wf(?,-,?).
4170		ground_inner_wf(_,_,WF) :-
4171	?	ground_inner_wait_flags(WF).
4172
4173		call_b_execute_operation2(Name,InState,OutState,ParamValues,ResultInputValues,ResultValues,false,Path,Info,WF,OR) :-
4174	?	runtime_profiler:profile_single_call(Name,unknownStateId, b_interpreter:
4175		b_execute_operation2(Name,_,InState,OutState,ParamValues,ResultInputValues,ResultValues,false,Path,Info,WF,OR)
4176		).
4177
4178		output_parameters_value(LocalState,InState,Results,_,WF,reads_result(Index,ID,_Type),bind(ID,Val)) :-
4179		nth1(Index,Results,ReadResultTID),!,
4180		def_get_texpr_id(ReadResultTID,ReadID),
4181		(lookup_value_without_check(ReadID,LocalState,InState,Val)
4182		-> true %check_not_undefined(Val,ReadID,ReadResultTID)
4183		; add_error_wf(output_parameters,'Could not obtain value for read output parameter: ',ReadID,ReadResultTID,WF),
4184		Val = term(undefined)).
4185		output_parameters_value(_LocalState,_InState,_Results,Info,WF,reads_result(_Index,ID,_Type),bind(ID,Val)) :-
4186		add_error_wf(output_parameters,'Could not obtain value for read output parameter: ',ID,Info,WF),
4187		Val = term(undefined).
4188
4189		% TO DO: use this ?
4190		%:- block check_not_undefined(-,?,?).
4191		%check_not_undefined(term(undefined),ReadID,ReadResultTID) :- !,
4192		% add_error(output_parameters_value,'Output parameter not assigned to: ',ReadID,ReadResultTID).
4193		%check_not_undefined(_,_,_).
4194
4195		:- use_module(probsrc(succeed_max),[assert_max_reached/1]).
4196		% ResultInputValues: in Atelier-B result parameters can also be read !
4197		b_execute_operation2(Name,Operation,InState,Updates,ParaValues,ResultInputValues,ResultValues,_TopLvl,TransInfo,_,_WF,_OR) :-
4198		ResultInputValues = [], % in this case the operation's behaviour also depends on current value of output variables
4199		lookup_cached_transitions(Name,InState,Info,Solutions),!,
4200		(member(max_reached,Info) -> assert_max_reached(Name) ; true),
4201	?	member(trans_cached(ParaValues,ResultValues,Updates,TransInfo),Solutions),
4202		create_full_operation(Name,ResultValues,ParaValues,ResultValues,Operation).
4203		% TODO: call operation with ParaValues if not found and max_reached is true !!
4204
4205		b_execute_operation2(Name,Operation,InState,NewOutState,ParaValues,ResultInputValues,ResultValues,
4206		TopLevel,TransInfo,Info,WF,OutputRequired) :-
4207		if(b_get_machine_operation_for_animation(Name,Results,Parameters,Body,OType,TopLevel,OpPos),
4208		true,
4209		(add_error_wf(b_interpreter,'Cannot find operation:',Name,Info,WF),fail)),
4210		%% % we do not want skip the evaluation of a guard of an operation with parameters
4211		(Info=unknown, TopLevel==true -> CallInfo=OpPos ; CallInfo=Info),
4212		push_wait_flag_call_stack_info(WF,operation_call(Name,ParaValues,CallInfo),WF2),
4213	?	b_execute_operation3(OType,Name,Operation,
4214		InState,NewOutState,
4215		Body,Parameters,ParaValues,Results,ResultInputValues,ResultValues,TopLevel,TransInfo,WF2,OutputRequired).
4216
4217		create_full_operation(Name,Results,ParaValues,ResultValues,FullOperation) :-
4218		Operation =.. [Name|ParaValues], % TO DO: catch if > 255 args (max_arity)
4219		( Results == [] -> /* we have an ordinary operation */
4220		FullOperation = Operation
4221		; FullOperation = '-->'(Operation,ResultValues)
4222		).
4223
4224		b_execute_operation3(classic,Name,Operation,InState,NewOutState,
4225		Body,Parameters,ParaValues,Results,ResultInputValues,NormalisedResultValues,TopLevel,
4226		[path(Path)], % as path is currently filtered out anyway and not stored !
4227		WF,OR) :-
4228		%print('Attempting Operation ----> '),print(Name),nl,
4229		empty_state(EmptyState),
4230	?	set_up_typed_localstate(Parameters,ParaValues,ParamTypedVals,EmptyState,LocalState,positive),
4231		l_expand_and_normalise_values(ParaValues,NormalisedParaValues,Parameters),
4232		% not useful for call_b_execute_operation2
4233		create_full_operation(Name,Results,NormalisedParaValues, % ditto
4234		NormalisedResultValues,Operation),
4235		set_up_undefined_localstate_with_predefined(Results,ResultInputValues,InState,NewInState),
4236		/* to avoid error messages with sequential composition (store_intermediate_updates) */
4237		check_additional_guard(TopLevel,LocalState,NewInState,WF),
4238		(TopLevel==true
4239	?	-> b_execute_top_level_statement(Body,LocalState,NewInState,OutState,WF,Path,OR)
4240	?	; b_execute_statement(Body,LocalState,NewInState,OutState,WF,Path,OR)
4241		),
4242		b_tighter_enumerate_all_values(ParamTypedVals,WF),
4243		% moved after execute for performance reasons; see PerformanceTests/ParameterEnumeration.mch
4244		% print_bt_message('Operation Successful ------> '),
4245		(preferences:preference(treat_outermost_pre_as_select,true),
4246		preferences:preference(require_operations_to_assign_all_outputs,true)
4247		-> ReportError = true ; ReportError = false),
4248		get_results(Results,OutState,NormalisedResultValues,NewOutState,ReportError,normalise_results,WF).
4249		b_execute_operation3(eventb_operation(ChangeSet,ParaValues,Operation),
4250		_Name,Operation, InState,Updates,
4251		TBody,Parameters,ParaValues,[],[],[],true,TransInfo,WF,OutputRequired) :-
4252		% TO DO: check if need to pass _OutputRequired to b_event
4253	?	b_execute_event_with_change_set_wf(TBody,Parameters,ParaValues,InState,ChangeSet,Updates,TransInfo,WF,OutputRequired).
4254
4255		:- use_module(b_global_sets,[add_prob_deferred_set_elements_to_store/3]).
4256		% additional guards can be set by the user to constrain/direct the execution of operations
4257		check_additional_guard(TopLevel,LocalState,State,WF) :-
4258		(TopLevel==true,
4259		bmachine:b_machine_temp_predicate(TempPred)
4260		/* an additional precondition typed in by the user */
4261		-> check_state_skeleton_bound(LocalState,LB),
4262		check_state_skeleton_bound(State,BB),
4263		check_additional_guard_when_bound(LB,BB,TempPred,LocalState,State,WF)
4264		; true
4265		).
4266
4267		:- block check_additional_guard_when_bound(-,?,?, ?,?,?), check_additional_guard_when_bound(?,-,?, ?,?,?).
4268		check_additional_guard_when_bound(_,_,TempPred,LocalState,State,WF) :-
4269		(debug_mode(on) -> print(check_additional_guard),nl, print_bexpr(TempPred),nl ; true),
4270		add_prob_deferred_set_elements_to_store(State,BState1,visible),
4271		b_test_boolean_expression(TempPred,LocalState,BState1,WF).
4272
4273		% additional properties can either be set by user or by command-line or by VALUES clause
4274		add_additional_properties(OldProperty,NewProperty) :-
4275		(bmachine:b_machine_temp_predicate(TempPred) % this overrides additional property !
4276		-> conjunct_predicates([TempPred,OldProperty],NewProperty)
4277		; findall(AddPred,b_machine_additional_property(AddPred),L),
4278		(L=[] -> NewProperty = OldProperty
4279		; conjunct_predicates([OldProperty|L],NewProperty)
4280		)
4281		).
4282
4283		% get removes results from OutState
4284		filter_results(Results,OutState,NewOutState,WF) :-
4285		get_results(Results,OutState,_ResultValues,NewOutState,false,do_not_normalise,WF).
4286		get_results(Results,OutState,ResultValues,NewOutState,ReportError,Normalise,WF) :-
4287		(Results==[] -> (ResultValues,NewOutState) = ([],OutState)
4288		; get_results1(Results,OutState,ResultValues,NewOutState,ReportError,Normalise,WF)).
4289		:- block get_results1(?,-,?,?,?,?,?).
4290		get_results1([],OutState,[],OutState,_ReportError,_Normalise,_WF).
4291		get_results1([R|Results],OutState,[NRV|ResultValues],NewOutState,ReportError,Normalise,WF) :-
4292		def_get_texpr_id(R,ResultId),
4293		lookup_and_delete_value(ResultId,RV,OutState,OutState2,ReportError,WF,Finished),
4294		get_results2(Finished,R,Results,RV,NRV,OutState2,ResultValues,NewOutState,ReportError,Normalise,WF).
4295		:- block get_results2(-,?,?,?,?,?,?,?,?,?,?).
4296		get_results2(_,R,Results,RV,NRV,OutState2,ResultValues,NewOutState,ReportError,Normalise,WF) :-
4297		(Normalise==normalise_results -> normalise_value_for_var(R,true,RV,NRV)
4298		;
4299		NRV=RV), % Maybe we should not normalise in CBC mode ?
4300		get_results1(Results,OutState2,ResultValues,NewOutState,ReportError,Normalise,WF).
4301
4302
4303
4304		/* ------------------------------------------------------------------ */
4305		/* SET UP CONSTANTS */
4306		/* ------------------------------------------------------------------ */
4307
4308		:- use_module(static_ordering).
4309
4310		:- volatile no_solution_found_for_constants/0, solution_found_for_partial_properties/0,
4311		properties_were_filtered/1,
4312		unsat_properties_component/2, unsat_properties_enumeration_warning/1, unsat_properties_abort_error/1,
4313		unsat_properties_conjunct_inside_component/4.
4314		:- dynamic no_solution_found_for_constants/0, solution_found_for_partial_properties/0,
4315		properties_were_filtered/1,
4316		unsat_properties_component/2, unsat_properties_enumeration_warning/1,
4317		unsat_properties_abort_error/1,
4318		unsat_properties_conjunct_inside_component/4.
4319
4320		reset_unsat_component_infos :-
4321		retractall(unsat_properties_component(_,_)),
4322		retractall(unsat_properties_enumeration_warning(_)),
4323		retractall(unsat_properties_abort_error(_)),
4324		retractall(unsat_properties_conjunct_inside_component(_,_,_,_)).
4325
4326		:- use_module(b_interpreter_components,[unsat_conjunct_inside_component/4, unsat_component_abort_error/1,
4327		unsat_component_enumeration_warning/1]).
4328		% store information about unsatisfiable components for later usage
4329		% will only be called when no solution found for components
4330		copy_unsat_component_infos :-
4331		unsat_component(X,FalseOrUnknown), % from b_interpreter_components
4332		assertz(unsat_properties_component(X,FalseOrUnknown)),fail.
4333		copy_unsat_component_infos :-
4334		unsat_component_enumeration_warning(X), % from b_interpreter_components
4335		assertz(unsat_properties_enumeration_warning(X)),fail.
4336		copy_unsat_component_infos :-
4337		unsat_component_abort_error(X), % from b_interpreter_components
4338		assertz(unsat_properties_abort_error(X)),fail.
4339		copy_unsat_component_infos :-
4340		unsat_conjunct_inside_component(X,BE,Status,Reason), % from b_interpreter_components
4341		assertz(unsat_properties_conjunct_inside_component(X,BE,Status,Reason)),fail.
4342		copy_unsat_component_infos.
4343
4344		get_unsat_component_status(Status) :-
4345		(unsat_conjunct_inside_component(_,_,false,_) -> Status = false
4346		; unsat_component(X,false),
4347		\+ unsat_component_abort_error(X) -> Status = false % what about enumeration warnings?
4348		; Status=unknown).
4349
4350		% the same, but work on facts copied by copy_unsat_component_infos
4351		get_unsat_properties_status(Status) :-
4352		(unsat_properties_conjunct_inside_component(_,_,false,_) -> Status = false
4353		; unsat_properties_component(X,false),
4354		\+ unsat_properties_abort_error(X) -> Status = false % what about enumeration warnings?
4355		; Status=unknown).
4356
4357
4358		all_unsat_components_marked_prob_ignore :-
4359		unsat_properties_conjunct_inside_component(_,_,unknown,'prob-ignore'), % at least one prob-ignore was used
4360		!,
4361		\+ non_ignore_unsat_component.
4362
4363		non_ignore_unsat_component :-
4364		unsat_properties_conjunct_inside_component(_,_,Status,Reason),
4365		\+ (Status = unknown, Reason = 'prob-ignore').
4366
4367		tcltk_unsatisfiable_components_exist :-
4368		unsat_or_unknown_properties_component_exists.
4369		unsat_or_unknown_properties_component_exists :-
4370		(unsat_properties_component(_,_) -> true). %unsat_or_unknown_component_exists,!.
4371
4372		%tcltk_unsatisfiable_components(list(UnsatComponents)) :-
4373		% findall(C,unsat_properties_component(C),UnsatComponents), UnsatComponents\=[].
4374
4375		get_property_components(Components) :-
4376		b_machine_has_constants_or_properties,
4377		b_get_properties_from_machine(Properties),
4378		add_additional_properties(Properties,NewProperty),
4379		bsyntaxtree:predicate_components(NewProperty,Components),!.
4380		get_property_components([]).
4381
4382		:- dynamic uses_implementable_integers/0.
4383		:- dynamic min_max_integer_value_used/2.
4384
4385
4386		tcltk_quick_describe_unsat_properties(list(FullDescr),STATUS) :-
4387		retractall(uses_implementable_integers),
4388		retractall(min_max_integer_value_used(_,_)), assertz(min_max_integer_value_used(none,none)),
4389		get_property_components(Components),
4390		(unsat_properties_conjunct_inside_component(_,_,false,_) -> STATUS='FALSE'
4391		; all_unsat_components_marked_prob_ignore -> STATUS = 'prob-ignore'
4392		; STATUS='UNKNOWN'
4393		),
4394		findall(TP, (unsat_properties_conjunct_inside_component(CompNr,P,_Status,_ReasonMsg), % find individual conjuncts
4395		% Status can be false or unknown
4396		nth1(CompNr,Components,component(FullPred,_Vars)),
4397		check_uses_implementable_integers(FullPred), % for min-max one may need to look at the entire component !
4398		translate_bexpression_with_limit(P,TrP),
4399		get_component_enum_warning_message(CompNr,EnumWarningAbortMsg),
4400		(EnumWarningAbortMsg = '' -> Prefix = '' ; Prefix = '\n '),
4401		get_span_msg(P,'\n ',SpanMsg),
4402		ajoin([' * ',TrP,Prefix,EnumWarningAbortMsg,SpanMsg,'\n'],TP)),
4403		D1),
4404		findall([Msg1,PS|DescrVars],
4405		(get_unsat_component_description(Components,CompNr,MaxCompNr,
4406		Size,PS,DescrVars,EnumWarningAbortMsg,SpanMsg),
4407		ajoin([' * Predicate Component ',EnumWarningAbortMsg,CompNr,'/',MaxCompNr,
4408		' (with ',Size,' conjunct(s))',SpanMsg, ':'],Msg1)),
4409		UC),
4410		append(UC,UCL), % join all component descriptions
4411		(D1=[]
4412		% TO DO: adapt message for enumeration warning
4413		-> Descr = D2,
4414		(UCL=[] -> D2 = ['The properties were satisfiable']
4415		; D2 = ['No solution found for the following predicates: '|UCL]
4416		)
4417		; Descr = ['The following properties prevented finding a solution:\n'|D12],
4418		% Comment: the predicate can trigger the computation of another earlier registered predicate
4419		% Example f = {1|->2} & f: A --> B & A = 1..5; A=1..5 triggers the check for f
4420		(UCL=[] -> D2=[]
4421		; D2 = ['\nIn addition no solution was found for the following predicates: '|UCL]
4422		),
4423		append(D1,D2,D12)),
4424		findall(W,other_warning(W),Warnings),
4425		(Warnings = [] -> FullDescr=Descr ; append(Descr,['\nWARNINGS/MESSAGES:'|Warnings],FullDescr)).
4426
4427		% called by predicate_debugger:
4428		get_unsat_component_predicate(CompNr,Predicate,Vars) :-
4429		unsat_properties_component(CompNr,_FalseOrUnknown),
4430		get_property_components(Components),
4431		nth1(CompNr,Components,component(Predicate,Vars)).
4432
4433		get_unsat_component_description(Components,CompNr,MaxCompNr,Size,PS,DescrVars,EnumWarningAbortMsg,SpanMsg) :-
4434		unsat_properties_component(CompNr,_),
4435		\+ unsat_properties_conjunct_inside_component(CompNr,_,_,_), % we have not yet dealt with this component in first findall above
4436		nth1(CompNr,Components,component(Pred,Vars)),
4437		length(Components,MaxCompNr),
4438		size_of_conjunction(Pred,Size),
4439		describe_constants(Vars,DescrVars),
4440		check_uses_implementable_integers(Pred), % store information in case it does use implementable integers for later user messages
4441		(debug_mode(on) -> Lim = 1500 ; Lim = 250),
4442		translate_bexpression_with_limit(Pred,Lim,PS),
4443		get_component_enum_warning_message(CompNr,EnumWarningAbortMsg),
4444		% note: sometimes we have a conjunction with empty span info, but different conjuncts (possibly from different files):
4445		get_span_msg(Pred,'\n ',SpanMsg).
4446
4447		get_span_msg(Pred,Prefix,SpanMsg) :-
4448		(extract_span_description(Pred,SpanStr) -> ajoin([Prefix,SpanStr],SpanMsg) ; SpanMsg = '').
4449
4450		get_component_enum_warning_message(CompNr,EnumWarningAbortMsg) :-
4451		(unsat_properties_enumeration_warning(CompNr)
4452		->(unsat_properties_abort_error(CompNr)
4453		-> EnumWarningAbortMsg = '[** with Enumeration Warning and WD-ERROR **] '
4454		; EnumWarningAbortMsg = '[* with Enumeration Warning *] ')
4455		; (unsat_properties_abort_error(CompNr)
4456		-> EnumWarningAbortMsg = '[** with WD-ERROR **] '
4457		; EnumWarningAbortMsg = '')
4458		).
4459
4460		describe_constants([],R) :- !,R=[].
4461		describe_constants(Vars,['* over identifiers : '|Vars]).
4462
4463		check_uses_implementable_integers(_) :- specfile:eventb_mode,!. % cannot use implementable integers
4464		check_uses_implementable_integers(_) :- uses_implementable_integers,!. % no need to check another component
4465		check_uses_implementable_integers(Pred) :-
4466		(uses_implementable_integers(Pred)
4467		-> assertz(uses_implementable_integers),
4468		retract(min_max_integer_value_used(Min,Max)),
4469		min_max_integer_value_used(Pred,Min,Max,NewMin,NewMax),
4470		assertz(min_max_integer_value_used(NewMin,NewMax))
4471		; true).
4472
4473		other_warning(W) :- uses_implementable_integers,
4474		preferences:get_preference(minint,MININT),
4475		preferences:get_preference(maxint,MAXINT),
4476		min_max_integer_value_used(Min,Max),
4477		( (number(Min),Min<MININT ; number(Max),Max>MAXINT)
4478		-> ajoin(['\n MININT...MAXINT only set to ',MININT,'..',MAXINT,' but integers used at least from ',Min,'..',Max],W)
4479		; (MAXINT < 127 ; MININT > -128)
4480		-> ajoin(['\n MININT...MAXINT possibly too small: ',MININT,'..',MAXINT],W)).
4481		% TO DO: we could also extract explicit integer values used in the component and compare them against MININT/MAXINT
4482		other_warning(W) :- bmachine_eventb:deferred_set_equality_without_enumeration_axioms(X,_Set),
4483		translate_bexpression_with_limit(X,XS),
4484		ajoin(['\n Set not recognized as enumerated: ',XS],W).
4485		% TO DO: generate warning if MAXINT/MININT small and NAT,NAT1 or INT was used in component(s) above
4486
4487		% call if tcltk_quick_describe_unsat_properties fails:
4488		% TODO: maxint warning above
4489		generate_unsat_properties_warnings :- uses_implementable_integers,
4490		preferences:get_preference(minint,MININT),
4491		preferences:get_preference(maxint,MAXINT),
4492		min_max_integer_value_used(Min,Max),
4493		(number(Min),Min<MININT ; number(Max),Max>MAXINT),
4494		ajoin(['MININT...MAXINT only set to ',MININT,'..',MAXINT,' but integers used at least from ',Min,'..',Max],Msg),
4495		add_warning(setup_constants_unknown,Msg),
4496		fail.
4497		generate_unsat_properties_warnings :-
4498		bmachine_eventb:deferred_set_equality_without_enumeration_axioms(X,Set),
4499		translate_bexpression_with_limit(X,TX),
4500		Eq = b(equal(X,Set),pred,[]),
4501		ajoin(['Deferred SET ',TX,' was not recognized as an enumerated set, you may want to use partition instead of the equality: '],Msg),
4502		add_warning(setup_constants_unknown,Msg,Eq,X),
4503		fail.
4504		generate_unsat_properties_warnings.
4505
4506		% -------------
4507
4508		% Complete is either complete_properties or partial_properties if properties were marked as ignore
4509		b_set_up_concrete_constants(NormalisedConstantsState,Complete) :-
4510		reset_unsat_component_infos,
4511		retractall(properties_were_filtered(_)),
4512		(no_solution_found_for_constants -> true ; assertz(no_solution_found_for_constants)),
4513		% preference(allow_incomplete_partial_setup_constants,AllowSkipping),
4514		reset_component_info(true),
4515		b_machine_has_constants_or_properties,
4516		b_get_machine_constants(UnsortedConstants),
4517		!,
4518		silent_mode(SilentMode),
4519	?	(SilentMode=on -> true ; bt_start_ms_timer('SETUP_CONSTANTS')), % TO DO: store time for unsat core
4520		b_get_non_ignored_properties_from_machine(NonIgnoredProperties,Excluded),
4521		(Excluded>0 % prob-ignore predicates were filtered
4522		-> assertz(properties_were_filtered(Excluded)),
4523		Complete1=partial_properties
4524		; Complete1=complete_properties
4525		),
4526		add_additional_properties(NonIgnoredProperties,Properties),
4527		project_onto_static_assertions(Properties,UnsortedConstants,PProperties,PUnsortedConstants),
4528	?	solve_properties(PProperties,PUnsortedConstants,ConstantsState,SatResult),
4529	?	(SilentMode=on -> true ; bt_stop_ms_timer('SETUP_CONSTANTS')),
4530		(SatResult=satisfiable -> Complete = Complete1
4531		; Complete = partial_properties,
4532		assert_solution_found_for_partial_properties),
4533		normalise_store(ConstantsState,NormalisedConstantsState),
4534		retractall(no_solution_found_for_constants). /* ensure that b_partial_set_up_concrete_constants fails */
4535		b_set_up_concrete_constants([],complete).
4536
4537
4538		% solve already projected and filtered properties and constants, return state with solution for constants
4539		% cbc_solve_timed almost does what we want; but looks at current state; see solve_free_aux
4540		% TODO: move this to a separate module and add cdclt
4541		solve_properties(PProperties,PUnsortedConstants,ConstantsState,SatResult) :-
4542		get_preference(use_solver_on_load,Solver),
4543	?	solve_properties(Solver,PProperties,PUnsortedConstants,ConstantsState,SatResult).
4544
4545		solve_properties(sat,Properties,_TypedConstants,ConstantsState,satisfiable) :- !,
4546	?	b2sat:solve_predicate_with_satsolver_free(Properties, ConstantsState,Result,[]),
4547		Result=solution(_).
4548		solve_properties('sat-z3',Properties,_TypedConstants,ConstantsState,satisfiable) :- !,
4549		b2sat:solve_predicate_with_satsolver_free(Properties, ConstantsState,Result,[use_satsolver(z3)]),
4550		Result=solution(_).
4551		solve_properties(cdclt,Properties,_TypedConstants,ConstantsState,satisfiable) :- !,
4552		cdclt_solver:cdclt_solve_predicate(Properties,_,Result),
4553		Result=solution(ConstantsState).
4554		solve_properties(clingo,Properties,_TypedConstants,ConstantsState,satisfiable) :- !,
4555		get_preference(maxNrOfInitialisations,MaxNrSols),
4556		b2asp:solve_pred_with_clingo(Properties,MaxNrSols,_,Result,_Exhaustive),
4557		% TODO: check if non_exhaustive and assert max_reached ?
4558		Result=solution(ConstantsState).
4559		solve_properties(kodkod,PProperties,PUnsortedConstants,ConstantsState,SatResult) :- !,
4560	?	solve_properties(prob,PProperties,PUnsortedConstants,ConstantsState,SatResult). % Kodkod processing is done elswehere
4561		solve_properties(prob,PProperties,PUnsortedConstants,ConstantsState,SatResult) :- !,
4562		(preferences:preference(use_static_ordering,true)
4563		-> sort_ids_by_usage(PUnsortedConstants,PProperties,Constants,no_warnings), % no_warnings as Ids could be used in operations, assertions, ...
4564		set_up_typed_localstate(Constants,_FreshVars,TypedVals,[],SortedState,positive),
4565	?	reorder_state(PUnsortedConstants,SortedState,ConstantsState)
4566		; Constants = PUnsortedConstants,
4567	?	set_up_typed_localstate(Constants,_FreshVars,TypedVals,[],ConstantsState,positive)
4568		),
4569		% now try and load saved constants from file for sub-machines when -cache is used:
4570	?	load_partial_constants(ConstantsState,PProperties,LPProperties), % Note: this can backtrack
4571		reset_component_info(true), % reset in case load_partial_constants backtracks! relevant for test 2112
4572		b_global_sets:static_symmetry_reduction_for_global_sets(ConstantsState),
4573	?	call_cleanup(b_trace_test_components_full(LPProperties,ConstantsState,TypedVals,SatResult),
4574		copy_unsat_component_infos).
4575		solve_properties(SolverName,Properties,_TypedConstants,ConstantsState,satisfiable) :-
4576		temporary_set_preference(z3_solve_for_animation, true,Chng),
4577		call_cleanup(smt_solvers_interface:smt_solve_predicate_free(SolverName, Properties, ConstantsState),
4578		reset_temporary_preference(z3_solve_for_animation,Chng)).
4579
4580
4581		b_trace_test_components_full(LPProperties,ConstantsState,TypedVals,SatResult) :-
4582		init_wait_flags_and_push_call_stack(no_wf_available,operation_call('SETUP_CONSTANTS',[],unknown),WF),
4583	?	b_trace_test_components_wf(LPProperties,ConstantsState,TypedVals,all,SatResult,complete,WF),
4584		ground_wait_flags(WF). % WF is just a dummy waitflag to pass call stack info
4585		%(unsat_or_unknown_properties_component_exists -> (!,fail) ; true). % otherwise some expressions were skipped; use partial_set_up
4586
4587		:- volatile project_properties_on_identifiers/1.
4588		:- dynamic project_properties_on_identifiers/1.
4589		set_projection_on_static_assertions(ALL) :-
4590		% set interpreter in mode which projects out all constants not needed
4591		% for static assertion checking; all variables are also projected out
4592		retractall(project_properties_on_identifiers(_)),
4593		(b_get_assertions(ALL,dynamic,[]) -> true
4594		; nl,print('*** WARNING: DYNAMIC B ASSERTIONS NOT EMPTY'),nl,nl),
4595	?	b_get_assertions(ALL,static,L),
4596		(L=[] -> nl,print('*** WARNING: NO STATIC B ASSERTIONS ***'),nl,nl ; true),
4597		conjunct_predicates(L,Conj),
4598		(debug_mode(on) -> print('Static Assertion: '),translate:print_bexpr(Conj),nl ; true),
4599		bsyntaxtree:predicate_identifiers(Conj,IDs),
4600		(debug_mode(on) -> print('IDS: '), print(IDs),nl ; true),
4601		assertz(project_properties_on_identifiers(IDs)).
4602
4603		% optionally project properties onto those required for checking assertions
4604		project_onto_static_assertions(Properties,Constants,NewProperties,NewConstants) :-
4605		%% set_projection_on_static_assertions(main), %% main or all %% set by probcli if we_need_only_static_assertions
4606		project_properties_on_identifiers(ProjIDs),
4607		bsyntaxtree:project_predicate_on_identifiers(Properties,ProjIDs,NewProperties,PIDs,_),
4608		sort(PIDs,SIPDs),
4609		debug_println(9,projecting(SIPDs)),
4610		include(keep_constant(SIPDs),Constants,NewConstants),!. % Constants is a typed identifier list.
4611		project_onto_static_assertions(Properties,Constants,Properties,Constants).
4612
4613		keep_constant(SIPDs,TypedID) :- get_texpr_id(TypedID,ID),ord_member(ID,SIPDs).
4614
4615
4616
4617		/* 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 */
4618		% called by partial_trans
4619		:- use_module(specfile,[get_specification_description/2]).
4620		b_partial_set_up_concrete_constants(NormalisedConstantsState) :-
4621		get_unsat_properties_status(Status), % Status is false or unknown
4622		no_solution_found_for_constants,
4623		set_error_context(operation('$partial_setup_constants',root)),
4624		(b_partial_set_up_concrete_constants2(NormalisedConstantsState,Status)
4625		-> clear_error_context, generate_unsat_properties_warnings
4626		; clear_error_context, generate_unsat_properties_warnings,fail).
4627
4628		b_partial_set_up_concrete_constants2(NormalisedConstantsState,Status) :-
4629		b_get_machine_constants(Constants),
4630		Constants \= [],
4631	?	(det_solution_for_constant_was_stored(Cst1) -> true), % we have found a solution for at least one constant
4632		%set_up_typed_localstate(Constants,[],ConstantsState), -> can create call_residue due to typing fd/2 values
4633		findall(bind(ID,_),(member(TID,Constants),def_get_texpr_id(TID,ID)),ConstantsState),
4634		formatsilent('SETUP_CONSTANTS not successful, but solutions were found for some constants (e.g., ~w):~n',[Cst1]),
4635		(fill_in_det_solutions(ConstantsState,FC) -> All=all ; All=some(Cst1)),
4636		(preference(allow_incomplete_partial_setup_constants,true)
4637		-> true
4638		; % fill_in_det_solutions will fail if not all constants valued and
4639		% if allow_incomplete_partial_setup_constants is false
4640		b_partial_set_up_error_messages(Status,All),
4641		All=all % only continue if all constants valued
4642		),
4643		normalise_store(FC,NormalisedConstantsState).
4644
4645		assert_solution_found_for_partial_properties :-
4646		(solution_found_for_partial_properties -> true
4647		; assertz(solution_found_for_partial_properties),
4648		(get_unsat_component_status(Status) -> b_partial_set_up_error_messages(Status,all)
4649		; add_internal_error('No unsat component: ',assert_solution_found_for_partial_properties),
4650		b_partial_set_up_error_messages(unknown,all))
4651		).
4652
4653		b_partial_set_up_error_messages(_Status,_All) :-
4654		get_preference(allow_incomplete_partial_setup_constants,true),!.
4655		b_partial_set_up_error_messages(Status,All1) :-
4656		get_specification_description(properties,PS),
4657		(All1=some(Cst1) -> All=some, TMSG = [', e.g., ',Cst1,')'] ; All=All1, TMSG = [')'] ),
4658		% TO DO: determine if time-out occurred or not
4659		(Status=false
4660		-> ajoin([PS,' are unsatisfiable (but ',All,' CONSTANTS valued'|TMSG],Msg),
4661		add_error_or_warning(All,setup_constants_inconsistent,Msg)
4662		; unsat_properties_abort_error(_)
4663		-> ajoin([PS,' are unknown due to well-definedness error(s) (but ',All,' CONSTANTS valued'|TMSG],Msg),
4664		add_error_or_warning(All,setup_constants_unknown,Msg)
4665		; unsat_component_enumeration_warning(_)
4666		-> ajoin([PS,' are unknown due to enumeration warning(s) (but ',All,' CONSTANTS valued'|TMSG],Msg),
4667		add_error_or_warning(All,setup_constants_unknown,Msg)
4668		; all_unsat_components_marked_prob_ignore
4669		-> ajoin([PS,' are unknown due to prob-ignore pragmas (but ',All,' CONSTANTS valued'|TMSG],Msg),
4670		add_message(setup_constants_unknown,Msg)
4671		;
4672		ajoin([PS,' are unknown (but ',All,' CONSTANTS valued'|TMSG],Msg),
4673		% typical message: but some CONSTANTS valued
4674		add_error_or_warning(All,setup_constants_unknown,Msg)
4675		).
4676
4677		:- use_module(probsrc(preferences),[get_prob_application_type/1]).
4678		add_error_or_warning(all,Category,Message) :- get_prob_application_type(rodin),!,
4679		add_warning(Category,Message). % if error occurs during LoadEventBModelCommand in ProB for Rodin, the command fails
4680		add_error_or_warning(_,Category,Message) :-
4681		add_error(Category,Message).
4682
4683
4684		:- use_module(store,[no_value_for_variable/2]).
4685		fill_in_det_solutions([],[]).
4686		fill_in_det_solutions([bind(Var,Val)|T],[bind(Var,FVal)|FT]) :-
4687		(det_solution_for_constant(Var,Val)
4688		-> (silent_mode(on) -> true ; write(' --det--> '),print_term_summary(bind(Var,Val))),
4689		FVal=Val
4690		; %format('No (deterministic) solution was found or stored for constant: ~w~n',[Var]), % message printed by det_solution_for_constant
4691		(preference(allow_incomplete_partial_setup_constants,true)
4692		-> no_value_for_variable(FVal,Var)
4693		; format('Aborting SETUP_CONSTANTS (set preference ALLOW_INCOMPLETE_SETUP_CONSTANTS to TRUE to allow ProB to proceed without having values for all CONSTANTS)~n',[]),
4694		fail
4695		)
4696		),
4697		fill_in_det_solutions(T,FT).
4698
4699
4700
4701		/* --------------------------------- */
4702
4703		:- use_module(b_state_model_check, [b_check_valid_state/1]).
4704
4705		% note: set_up_initialisation for CBC checks does not use this predicate
4706		b_initialise_machine(ConstantsState,NormalisedInitialVarsState,FullInitialState,Path) :-
4707	?	if(b_initialise_machine2(ConstantsState,NormalisedInitialVarsState,FullInitialState,Path),
4708		true,
4709		(\+ logged_error(initialisation_fails,_,_,_), % we have already provided a more precise error message
4710		\+ abort_error_exists_in_context_state(initialisation_fails), % ditto as a state error
4711		(bmachine:b_machine_temp_predicate(TempPred)
4712		-> add_message(initialisation_fails,'INITIALISATION FAILS with provided predicate: ',TempPred,TempPred)
4713		; b_get_initialisation_from_machine(Stmt,_OType)
4714		-> add_error(initialisation_fails,'INITIALISATION FAILS','',Stmt)
4715		; add_error(initialisation_fails,'MACHINE has no INITIALISATION clause')
4716		),
4717		fail)
4718		).
4719
4720		b_initialise_machine2(ConstantsState,NormalisedInitialVarsState,FullInitialState,Path) :-
4721		/* InitialVarsState is an ouput */
4722		b_get_initialisation_from_machine(InitStatement,OType),
4723		( InitStatement=[] ->
4724		Path = [],
4725		add_message(b_initialise_machine,'Machine has no INITIALISATION statement(s)!'),
4726		NormalisedInitialVarsState = [],
4727		FullInitialState = ConstantsState
4728		; OType == classic ->
4729		Path = [path(PathInfo)],
4730		b_get_machine_variables(DeclaredVars),
4731		set_up_undefined_localstate(DeclaredVars,ConstantsState,NewInState),
4732		/* this is if the INITIALISATION has a sequential composition; to avoid error messages */
4733		get_texpr_info(InitStatement,PosInfo),
4734		init_wait_flags_with_call_stack(WF,[operation_call('INITIALISATION',[],PosInfo)]),
4735		(bmachine:b_machine_temp_predicate(_)
4736		-> InitStatement2=InitStatement /* avoid enumerating each init statement in parallel in case additional guard links them */
4737		; translate_init_statements(InitStatement,InitStatement2)
4738		),
4739		check_additional_guard(true,InitialVarsState,ConstantsState,WF),
4740	?	b_execute_statement(InitStatement2,[],NewInState,InitialVarsState,WF,PathInfo),
4741		% Warning: in Z mode (e.g. test 565) the variable skeleton may not yet be set up !
4742		sort_variable_binding(InitialVarsState,NormalisedInitialVarsState),
4743		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
4744		split_names_and_types(DeclaredVars,DeclaredNames,DeclaredTypes),
4745	?	ground_wait_flags(WF),
4746
4747		b_enumerate_values_in_store(DeclaredNames,DeclaredTypes,_,InitialVarsState,WF) %% MOVED HERE TO AVOID that target values are enumerated before initialisation effect computed
4748		; OType = eventb_operation(_ChangeSet,ParaValues,_Operation) ->
4749		prepare_eventb_initialisation(ConstantsState,InitialVarsUnNormState,FullInitialUnNormState),
4750		get_texpr_expr(InitStatement,
4751		rlevent(_Name,_Sec,_Stat,Parameters,_Grd,_Thm,_Act,_VWit,_PWit,_Unmod,_AbsEv)),
4752	?	b_execute_event('initialisation',InitStatement,Parameters,ParaValues,ConstantsState,FullInitialUnNormState,Path),
4753		normalise_store(InitialVarsUnNormState,NormalisedInitialVarsState),
4754		normalise_store(FullInitialUnNormState,FullInitialState) % a bit of redundant work here; we do the work twice and try to normalise constants again !
4755		),
4756		b_check_valid_state(FullInitialState).
4757
4758		% ensure that the variables always appear in the same order as reported by b_get_machine_variables:
4759		% 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 ??
4760		sort_variable_binding(Store,SortedStore) :- %print(sort_variable_binding(Store,SortedStore)),nl,
4761		b_get_machine_variables(Variables),
4762		sort_aux(Variables,Store,[],SortedStore).
4763		sort_aux([],S,Acc,NormRes) :- reverse(Acc,Res),
4764		normalise_store(Res,NormRes),
4765		(S=[] -> true ; add_internal_error('Unknown variable bindings: ',S)).
4766		sort_aux([TVar|T],Store,Acc,Res) :- def_get_texpr_id(TVar,ID),
4767		bselect(ID,Val,Store,Rest),
4768		sort_aux(T,Rest,[bind(ID,Val)|Acc],Res).
4769
4770		:- block bselect(?,?,-,?). % in Z mode (e.g. test 565) the variable skeleton may not yet be set up !
4771		bselect(ID,Val,[bind(ID1,Val1)|T],Rest) :- % we assume ID1 is nonvar
4772		(ID=ID1 -> Val=Val1,T=Rest
4773		; Rest = [bind(ID1,Val1)|RT],
4774		bselect(ID,Val,T,RT)).
4775
4776		prepare_eventb_initialisation(ConstantsState,InitialVarsState,FullInitialState) :-
4777		b_get_machine_variables(Variables),
4778		empty_state(Empty),
4779		set_up_typed_localstate(Variables,_,_,Empty,InitialVarsState,positive),
4780		% NormalisedInitialVarsState = InitialVarsState, % TO DO : check that b_event normalises this
4781		combine_updates(InitialVarsState,ConstantsState,FullInitialState).
4782		% put constants at end, to be compatible with b_initialise_machine2 and expand_const_and_vars order and e.g. ltsmin
4783
4784
4785
4786		reset_b_interpreter :-
4787		%reset_partial_evaluator,
4788		retractall(project_properties_on_identifiers(_)),
4789		reset_unsat_component_infos,
4790		retractall(no_solution_found_for_constants),
4791		retractall(solution_found_for_partial_properties).
4792
4793		:- use_module(eventhandling,[register_event_listener/3]).
4794		:- register_event_listener(clear_specification,reset_b_interpreter,
4795		'Reset B-Interpreter Memo Table & Unsat Components.').