1		% (c) 2009-2025 Lehrstuhl fuer Softwaretechnik und Programmiersprachen,
2		% Heinrich Heine Universitaet Duesseldorf
3		% This software is licenced under EPL 1.0 (http://www.eclipse.org/org/documents/epl-v10.html)
4
5
6		:- module(b_interpreter,
7		[b_test_boolean_expression/4, b_test_boolean_expression/6,
8		%b_test_boolean_expression_wf/3,
9		b_test_boolean_expression_cs/5,
10		b_test_boolean_expression_for_ground_state/4, b_test_boolean_expression_for_ground_state/5,
11		% b_det_test_boolean_expression/6,
12		b_not_test_boolean_expression/4, b_not_test_boolean_expression/6,
13		%b_not_test_boolean_expression_wf/3,
14		b_not_test_boolean_expression_cs/5,
15
16		b_convert_bool/5,
17		b_convert_bool_timeout/7,
18		b_compute_expression/5,
19
20		b_execute_top_level_statement/7,
21		b_execute_statement_nowf/5,
22
23		b_compute_expression_nowf/4, b_compute_expression_nowf/6, b_compute_expression_nowf/7,
24		b_compute_explicit_epression_no_wf/6, b_compute_explicit_epression_no_wf/7,
25
26		b_set_up_concrete_constants/2, b_partial_set_up_concrete_constants/1,
27		b_initialise_machine/4,
28
29		b_execute_top_level_operation_update/5, b_execute_top_level_operation_wf/8,
30
31		convert_list_of_expressions_into_set_wf/4,
32		%state_satisfies_negation_of_invariant/1,
33
34		b_state_violates_invariant/2,
35		state_violates_assertions/2,
36		analyse_invariant_for_state/1,
37
38		insert_before_substitution_variables/5, % add $0 values to a store
39
40		try_lookup_value_in_store_and_global_sets/3, lookup_value_in_store_and_global_sets_wf/7,
41		set_up_typed_localstate/6, set_up_typed_localstate2/8,
42		%set_up_localstate_for_let/7,
43
44		set_projection_on_static_assertions/1,
45
46		tcltk_unsatisfiable_components_exist/0,
47		tcltk_quick_describe_unsat_properties/2,
48
49		get_unsat_component_predicate/3,
50		properties_were_filtered/1, % true if PROPERTIES / axioms filtered due to prob-ignore pragmas
51		b_generate_for_all_list_domain_nolwf/8 % for predicate_evaluator
52		]).
53
54		:- meta_predicate not_with_enum_warning_and_possible_delay(0,-,?,?,?).
55		:- meta_predicate not_with_enum_warning_delay(0,-,?,?,?,?).
56
57		%:- use_module('../extensions/profiler/profiler.pl').
58		%:- use_module('../extensions/profiler/profiler_te.pl').
59		%:- enable_profiling(b_test_boolean_expression/4).
60		%:- enable_profiling(b_test_boolean_expression_cs/5).
61
62		:- use_module(kernel_objects).
63		:- use_module(bsets_clp).
64		:- use_module(delay).
65
66
67		:- use_module(kernel_mappings).
68		:- use_module(b_global_sets).
69		:- use_module(store).
70		:- use_module(library(lists)).
71		:- use_module(library(ordsets)).
72		:- use_module(library(avl)).
73
74		:- use_module(b_global_sets).
75		:- use_module(bmachine).
76		:- use_module(b_enumerate, [b_enumerate_values_in_store/5,
77		b_tighter_enumerate_all_values/2, b_tighter_enumerate_values_in_ctxt/3]).
78		:- use_module(debug).
79		:- use_module(performance_messages).
80		:- use_module(self_check).
81		:- use_module(tools).
82
83		:- use_module(module_information,[module_info/2]).
84		:- module_info(group,interpreter).
85		:- module_info(description,'This module provides the basic interpreter for expressions, predicates and substitutions.').
86
87		:- use_module(preferences).
88		:- use_module(error_manager).
89		:- use_module(typechecker).
90		:- use_module(specfile,[state_corresponds_to_initialised_b_machine/2
91		,state_corresponds_to_set_up_constants_only/2]).
92
93		:- use_module(bsyntaxtree).
94
95		:- use_module(translate).
96
97		:- use_module(kernel_waitflags).
98		:- use_module(kernel_reals).
99		:- use_module(kernel_records).
100
101		:- use_module(kodkodsrc(kodkod),[kodkod_request/5]).
102
103		:- use_module(custom_explicit_sets).
104		:- use_module(closures,[is_symbolic_closure/1,
105		mark_closure_as_symbolic/2, mark_closure_as_recursive/2, mark_closure/3]).
106
107		:- use_module(state_space).
108		:- use_module(b_interpreter_eventb).
109		:- use_module(tools_printing,[print_term_summary/1,print_functor/1]).
110		:- use_module(value_persistance,[load_partial_constants/3,lookup_cached_transitions/4]).
111		:- use_module(extrasrc(b_expression_sharing),[is_lazy_let_identifier/1]).
112		:- use_module(bool_pred,[negate/2]).
113		:- use_module(smt_solvers_interface(smt_solvers_interface),[smt_add_predicate/5]).
114
115		:- use_module(debug).
116		:- use_module(external_functions).
117
118		:- use_module(static_ordering,[sort_ids_by_usage/4,reorder_state/3]).
119		%:- use_module(bsyntaxtree,[predicate_has_ignore_pragma/1]).
120		:- use_module(tools_lists,[exclude_count/4, optimized_nth1/3]).
121		:- use_module(tools_meta, [safe_time_out/3]).
122
123		:- set_prolog_flag(double_quotes, codes).
124
125		/* ----------------------------------*/
126
127		/* For partial evaluation */
128
129		%:- use_module('~/cvs_root/cogen2/logen_source/runtime/logen_dispatcher.pl').
130
131		% new profiler
132		%:- use_module('../extensions/profiler/profiler.pl').
133		%:- use_module('../extensions/profiler/profiler_te.pl').
134		%:- enable_profiling_naming(b_interpreter:b_state_violates_invariant_aux/2,name).
135
136		%name(b_interpreter:b_state_violates_invariant_aux,_,INVERIANT).
137
138		%b_state_violates_invariant(ID,State) :-
139		% b_intepreter:b_state_violates_invariant_aux(ID,State).
140
141		% old profiler
142		:- use_module(runtime_profiler,[profile_single_call/3]).
143
144		% called by force_check_invariantKO and indirectly by model_checker (State was prepare_state_for_specfile_trans )
145		b_state_violates_invariant(ID,State) :-
146		b_state_violates_invariant_aux(ID,State).
147
148		b_state_violates_invariant_aux(ID,CurBState) :-
149		retract(specialized_inv(ID,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,_), %get_texpr_type(Arg1,integer),
685		preferences:preference(use_clpfd_solver,true),!,
686		(Arg2 = b(_,integer,_) -> true ; add_internal_error('Type error in AST, not wrapped integer: ',Arg2)),
687	?	b_test_arith_equal_boolean_expression(Arg1,Arg2,LocalState,State,WF).
688		b_test_atomic_equal_boolean_expression(Arg1,Arg2,Info,LocalState,State,WF) :-
689	?	member(prob_annotation('LAMBDA-EQUALITY'),Info),
690		\+ simple_expression(Arg2),
691		is_lambda_result_id(Arg1), %get_texpr_id(Arg1,'_lambda_result_'), % ensure we have not renamed it to was_lambda_result ?
692		!, % this is an equality for the result of a lambda abstraction; only evaluate at the end
693		b_compute_expression(Arg1,LocalState,State,SV1,WF), % this is the lambda result identifier _lambda_result_
694		%get_enumeration_finished_wait_flag(WF,EWF),
695		%get_wait_flag(10000,lambda_result,WF,EWF),
696		% compute deterministic parts of Arg2 in wf0 phase: avoid computing this stuff over again
697		%print('DELAY: '), translate:print_bexpr(Arg2),nl,
698	?	kernel_waitflags:copy_wf01e_wait_flags(WF,WF2), b_compute_expression(Arg2,LocalState,State,SV2,WF2),
699		get_last_wait_flag(lambda_result,WF,EWF),
700		ground_value_check(SV2,G2),
701		when((nonvar(G2);nonvar(SV1);nonvar(EWF)),b_lambda_result_equal_boolean_expression(SV1,SV2,WF,EWF,WF2)).
702		b_test_atomic_equal_boolean_expression(Arg1,Arg2,Info,LocalState,State,WF) :-
703		(LocalState = []
704		-> true % only check if we are at the outer level
705		% (not inside a quantifier,...) or if we have CSE introduzed lazy_lets:
706		; preferences:preference(use_common_subexpression_elimination,true)
707		% TO DO: check that we have only added @nr to local state from lazy_let; ADD INFO FIELD
708		),
709		get_texpr_type(Arg1,Type1), is_set_type(Type1,SetType1),
710		% previously we required SetType1 = couple(_,_)
711		get_texpr_id(Arg1,ID),
712		% we could check: \+ get_texpr_id(Arg2,_), we do not need to treat simple equations like ID=ID2; unless for memo?
713	?	(abstract_constant(ID,_) % check if ABSTRACT_CONSTANT
714		-> Kind=abstract,
715	?	kernel_objects:max_cardinality(Type1,MaxCard1),
716		(number(MaxCard1) % check that type is large enough to warrant recursive or symbolic treatment
717		-> (MaxCard1>100 -> true ; constant_variable_marked_as_memo(ID))
718		; true)
719		; %fail,
720	?	concrete_constant(ID,_)
721		-> Kind=concrete,
722		(constant_variable_marked_as_expand(ID)
723		-> true % note: we also check for expand annotation in store (expand_closure_value),
724		% but it is useful to expand ID already here to ease checking PROPERTIES
725		; constant_variable_marked_as_memo(ID))
726		%; b_is_unused_constant(ID) -> ABSTRACT=true % TO DO: check if ID not used somewhere else in Properties ??!!
727		),
728		% in future: we may do size change analysis, or something like that to check that we have properly defined
729		% recursive function
730		debug_format(19,'Equation defining ~w constant: ~w~n',[Kind,ID]),
731		!,
732		(constant_variable_marked_as_expand(ID) -> SymArg2 = Arg2 ; mark_bexpr_as_symbolic(Arg2,SymArg2)),
733	?	b_add_constant_definition(Kind,ID,Info,Arg1,SetType1,SymArg2,LocalState,State,WF).
734		b_test_atomic_equal_boolean_expression(Arg1,Arg2,Info,LocalState,State,WF) :-
735		constants_profiling_on,
736		get_texpr_id(Arg1,ID),b_is_constant(ID), !,
737		% Note: does not yet keep track of arithmetic equalities above
738		b_compute_expression(Arg1,LocalState,State,SV1,WF),
739		push_constant_def_equality_call_stack(WF,ID,Info,WF2),
740		start_profile(ID,T1),
741		b_compute_expression(Arg2,LocalState,State,SV2,WF2),
742		get_waitflags_phase(WF,Phase),
743		stop_constant_profile(SV2,Phase,ID,[],T1), % normal constant, not symbolic, memoized or recursive
744		start_propagation_profile(ID,T2,CstL1),
745		kernel_call_predicate_equal_object_optimized(SV1,SV2,WF),
746		stop_propagation_profile(SV2,ID,T2,CstL1).
747		b_test_atomic_equal_boolean_expression(Arg1,Arg2,_Info,LocalState,State,WF) :-
748	?	b_compute_expression(Arg1,LocalState,State,SV1,WF),
749	?	b_compute_expression(Arg2,LocalState,State,SV2,WF),
750	?	kernel_call_predicate_equal_object_optimized(SV1,SV2,WF).
751
752
753
754		% treat equality ID = Symbolic Function (or relation/set)
755		b_add_constant_definition(Kind,ID,Info,Arg1,SetType1,SymArg2,LocalState,State,WF) :-
756		% observe CTRL-C: e.g., in data validation models these abstract functions can be very large and costly to compute
757	?	observe_user_interrupt_signal(computing_value_for_abstract_constant(ID),SymArg2,
758		b_add_constant_definition_aux(Kind,ID,Info,Arg1,SetType1,SymArg2,LocalState,State,WF)).
759
760		:- use_module(runtime_profiler,[start_profile/2,
761		stop_constant_profile/5, constants_profiling_on/0]).
762		b_add_constant_definition_aux(Kind,ID,_Info,Arg1,SetType1,SymArg2,LocalState,State,WF) :-
763		preference(use_function_memoization,MemoPref), % true, false or default
764		MemoPref \= false, % turned off
765		( MemoPref = true, Kind=abstract ;
766		constant_variable_marked_as_memo(ID)), % description(memo) as info field using @desc memo pragma; see
767		!,
768		start_profile(ID,T1),
769		b_compute_expression(Arg1,LocalState,State,SV1,WF), % the identifier
770		(SymArg2 = b(recursive_let(TID,Body),_,_)
771		-> get_texpr_id(TID,RecID),
772		b_compute_expression(Body,[bind(RecID,RedIDVal)|LocalState],State,SV2,WF),
773		RecValue='$recursion_value'(RedIDVal), IDInfo = [recursive_memo]
774		; b_compute_expression(SymArg2,LocalState,State,SV2,WF),
775		RecValue='$no_recursion', IDInfo = [memoized]
776		),
777		get_waitflags_phase(WF,Phase), stop_constant_profile(SV2,Phase,ID,IDInfo,T1),
778		(nonvar(SV2), SV2 \= closure(_,_,_)
779		-> % value fully computed; no need to memoize
780		debug_println(19,not_memoizing(ID)),
781		kernel_call_predicate_equal_object_optimized(SV1,SV2,WF)
782		; (nonvar(SV2) -> mark_closure_as_symbolic(SV2,SV3) ; SV3=SV2),
783		memoization:register_memoization_function(ID,SV3,SetType1,RecValue,MEMOID,SV4),
784		debug_println(19,marking_for_memoization(ID,MEMOID)),
785		kernel_call_predicate_equal_object_optimized(SV1,SV4,WF)
786		).
787		b_add_constant_definition_aux(_Kind,ID,Info,Arg1,_,SymArg2,LocalState,State,WF) :-
788		start_profile(ID,T1),
789		b_compute_expression(Arg1,LocalState,State,SV1,WF), % the identifier ID
790		push_constant_def_equality_call_stack(WF,ID,Info,WF2),
791	?	b_compute_expression(SymArg2,LocalState,State,SV2,WF2),
792		(constant_variable_marked_as_expand(ID)
793		-> IDInfo = [marked_as_expand],
794		b_expand_compute_comprehension_set(SV2,Info,SV3,WF2)
795		; definitely_expand_this_explicit_set(SV2) % check for a few patterns which should definitely be expanded;
796		% in case user puts a set accidentally into the ABSTRACT_CONSTANTS section
797		-> IDInfo = [automatic_expand],
798		b_expand_compute_comprehension_set(SV2,Info,SV3,WF2)
799		; var(SV2) -> IDInfo = [], SV3=SV2
800		; IDInfo = [], % it is from ABSTRACT_CONSTANTS, but this info is already stored
801		mark_closure_as_symbolic(SV2,SV3)
802		),
803		get_waitflags_phase(WF,Phase), stop_constant_profile(SV3,Phase,ID,IDInfo,T1),
804		start_propagation_profile(ID,T2,CstL1),
805		kernel_call_predicate_equal_object_optimized(SV1,SV3,WF),
806		% profile propagation time and what constants are grounded
807		stop_propagation_profile(SV3,ID,T2,CstL1).
808
809		push_constant_def_equality_call_stack(WF,ID,Pos,WF2) :-
810		((constants_profiling_on ; get_preference(provide_trace_information,true))
811		-> push_wait_flag_call_stack_info(WF,
812		id_equality_evaluation(ID,constant,Pos),WF2)
813		; WF2=WF).
814
815		start_propagation_profile(ID,T1,CstL1) :-
816		(constants_profiling_on -> findall(Cst1,det_solution_for_constant_was_stored(Cst1),CstL1) ; CstL1=[]),
817		start_profile(ID,T1).
818		stop_propagation_profile(SV3,ID,T1,CstL1) :-
819		(constants_profiling_on
820		-> findall(Cst2,det_solution_for_constant_was_stored(Cst2),L2),
821		append(CstL1,New,L2), debug_format(9,'Propagation of value for ~w instantiated ~w~n',[ID,New]),
822		IDInfo2 = [instantiates(New)]
823		; IDInfo2 = []),
824		stop_constant_profile(SV3,propagate_value,ID,IDInfo2,T1).
825
826		% treat not(Arg1 = Arg2) predicates
827		b_test_atomic_not_equal_boolean_expression(Arg1,Arg2,_Info,LocalState,State,WF) :-
828		get_texpr_type(Arg1,boolean),!, % special treatment : not_equal_object has no type information
829		b_compute_expression(Arg1,LocalState,State,B1,WF),
830		b_compute_expression(Arg2,LocalState,State,B2,WF),
831		negate(B1,B2). % from bool_pred
832		b_test_atomic_not_equal_boolean_expression(Arg1,Arg2,_Info,LocalState,State,WF) :-
833		get_texpr_type(Arg1,integer),
834		preferences:preference(use_clpfd_solver,true),
835		!,
836		% Note: calling b_compute_arith_expression will also instantiate a variable to at least the int(_) skeleton; thereby enabling propagation
837		% this is potentially better than calling the default versions of the predicates, which may wait until the int(_) skeleton is set up before propagation
838	?	b_compute_arith_expression(Arg1,LocalState,State,CLPFD_Expr1,WF),
839	?	b_compute_arith_expression(Arg2,LocalState,State,CLPFD_Expr2,WF),
840		clpfd_interface:clpfd_neq_expr(CLPFD_Expr1,CLPFD_Expr2).
841		b_test_atomic_not_equal_boolean_expression(Arg1,Arg2,_Info,LocalState,State,WF) :-
842	?	b_compute_expression_symbolic(Arg1,LocalState,State,SV1,WF),
843	?	b_compute_expression_symbolic(Arg2,LocalState,State,SV2,WF),
844		kernel_call_predicate_not_equal_object(SV1,SV2,WF,not_equal(Arg1,Arg2)).
845		% Note: symbolic case occurs for symbolic abstract constants f when using DOUBLE_EVALUATION
846		% in the evaluation view which are defined by f = %x... when checking f /=
847
848		% a version of b_compute_expression which does not try to expand comprehension sets
849		% TODO: deal with other constructs which merit symbolic treatment; union of comprehension sets, ...
850		% (see line 147 in AMASS_mchs/oriented_abscissa.mch)
851		b_compute_expression_symbolic(Arg,LocalState,State,Val,WF) :-
852		(Arg = b(comprehension_set(PP,CC),_,InfoCS) % second arg is a comprehension set;
853		-> % print(symbolic(PP)),nl,
854	?	b_compute_comprehension_set_symbolic(PP,CC,InfoCS,LocalState,State,Val,WF)
855	?	; b_compute_expression(Arg,LocalState,State,Val,WF)
856		).
857		% ditto for already de-constructed b/3 expression:
858		b_compute_expression2_symbolic(comprehension_set(PP,CC),_,InfoCS,LocalState,State,Val,WF) :- !,
859		b_compute_comprehension_set_symbolic(PP,CC,InfoCS,LocalState,State,Val,WF).
860		b_compute_expression2_symbolic(Arg,Type,Info,LocalState,State,Val,WF) :-
861		b_compute_expression2(Arg,Type,Info,LocalState,State,Val,WF).
862
863		simple_expression(b(A,_,_)) :- simple_expression_aux(A).
864		simple_expression_aux(boolean_true).
865		simple_expression_aux(boolean_false).
866		simple_expression_aux(empty_set).
867		simple_expression_aux(empty_sequence).
868		simple_expression_aux(integer(_)).
869		simple_expression_aux(max_int).
870		simple_expression_aux(min_int).
871		simple_expression_aux(string(_)).
872		simple_expression_aux(value(_)).
873
874
875		is_lambda_result_id(b(identifier('_lambda_result_'),_,_)).
876		% at the moment we only detect those identifiers; the info field is currently not updated for _was_lambda_result_
877		% and not available in other treatmens of _lambda_result_ (in b_enumerate)
878		%is_lambda_result_id(b(identifier(X),_,Info)) :-
879		% memberchk(lambda_result,Info).
880		% (X=='_lambda_result_' -> (memberchk(lambda_result,Info) -> true ; format('~n*** _lambda_result_ without info: ~w~n~N',[Info])) ; memberchk(lambda_result,Info)).
881
882		%:- block b_lambda_result_equal_boolean_expression(-,?,?, -,?). % we now use when above
883		% only compute lambda result when finished finding domain element, i.e., _EWF is grounded
884		b_lambda_result_equal_boolean_expression(SV1,SV2,WF,EWF,WF2) :-
885		kernel_call_predicate_equal_object_optimized(SV1,SV2,WF),
886		% print(' LAMBDA : '), print((SV1,_EWF)),nl,
887		% the inner waitflags are for evaluating the lambda_result Expression; unless there is a WD issue this should
888		% never fail; we can delay the enumeration as much as possible
889		% NOTE: even if SV2 is ground, Arg2 may not be (e.g., if Arg2 = prj2(..,..)(NotGr,Ground))
890	?	blocking_ground_copied_wait_flags(WF2,EWF). % without when we will ground WF0 which is shared with outer WF-store
891		:- block blocking_ground_copied_wait_flags(?,-).
892		blocking_ground_copied_wait_flags(WF2,_) :-
893	?	ground_constraintprop_wait_flags(WF2). % do not ground EF flag, as shared with outer WF and WF2 is copied
894
895		% TO DO: add avl_set+closure expansion
896		%b_test_member_expression(Expr,El,_Set,_LocalState,_State,_WF) :-
897		% print('test member: '),print_bexpr(Expr),nl,fail.
898		b_test_member_expression(TElem,b(Set,Type,Info),LocalState,State,WF) :-
899	?	b_test_member_expression2(Set,Type,Info,TElem,LocalState,State,WF).
900
901		% new profiler
902		%:- use_module('../extensions/profiler/profiler.pl').
903		%:- use_module('../extensions/profiler/profiler_te.pl').
904		%:- enable_profiling(b_test_member_expression2/7).
905
906		% old profiler
907		%:- use_module(covsrc(hit_profiler)).
908
909		b_test_member_expression2(comprehension_set(Par,Cond),_Type,_Info,El,LocalState,State,WF) :-
910		% used to call in next clause below: b_generate_closure_if_necessary(Par,Cond,LocalState,State,SetValue,WF) /* will not expand closure */
911		/* 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 */
912		/* new version buys about 6 % for {x| x:1..400000 & x:{n|n >= 9000 & n<= 600000 & n mod 100 = 0}} (Sep 3 2014) */
913		set_up_typed_localstate(Par,ValueList,_TypedVals,LocalState,NewLocalState,positive),
914		!,
915		convert_list_into_pairs(ValueList,ElementVal),
916		b_compute_expression(El,LocalState,State,ElementVal,WF),
917		b_test_boolean_expression(Cond,NewLocalState,State,WF).
918		b_test_member_expression2(SymbolicSetConstant,_Type,_Info,El,LocalState,State,WF) :-
919		%hit_profiler:add_profile_hit(SymbolicSetConstant),
920		cst_in_boolean_type(SymbolicSetConstant,Module:Kernel_predicate),!, % two cases : string_set and integer_set
921		b_compute_expression(El,LocalState,State,ElValue,WF),
922		functor(KernelCall,Kernel_predicate,2),
923		arg(1,KernelCall,ElValue),
924		arg(2,KernelCall,WF),
925		% print_message(cst_in_boolean_type_call(KernelCall)),
926		kernel_call_predicate(KernelCall,Module,WF,SymbolicSetConstant). % should be member(... SymbolicSetConstant)
927		b_test_member_expression2(Expression,_Type,Info,El,LocalState,State,WF) :-
928		functor(Expression,BOP,2),
929		binary_in_boolean_type(BOP,Module:Kernel_predicate),!,
930		b_compute_expression(El,LocalState,State,ElValue,WF),
931		arg(1,Expression,Arg1),arg(2,Expression,Arg2),
932		(binary_in_definitely_true(BOP,ElValue)
933		-> % no need to compute arguments; unless required for WD:
934		check_well_defined(Arg1,LocalState,State,WF),
935		check_well_defined(Arg2,LocalState,State,WF)
936		; b_compute_expression(Arg1,LocalState,State,SV1,WF),
937	?	b_compute_expression(Arg2,LocalState,State,SV2,WF),
938		opt_push_wait_flag_call_stack_info(WF,b_operator_call(member,[ElValue,b_operator(BOP,[SV1,SV2])],Info),WF2),
939		% 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,
940	?	binary_in_kernel_call(Module,Kernel_predicate,ElValue,SV1,SV2,WF2,Expression)
941		).
942		b_test_member_expression2(Expression,_Type,Info,El,LocalState,State,WF) :-
943		functor(Expression,UnOP,1),
944		unary_in_boolean_type(UnOP,Module:Kernel_predicate),!,
945		b_compute_expression(El,LocalState,State,ElValue,WF),
946		arg(1,Expression,Arg1),
947		(unary_in_definitely_true(UnOP,ElValue)
948		-> % no need to compute arguments; unless required for WD:
949		check_well_defined(Arg1,LocalState,State,WF)
950		; b_compute_expression(Arg1,LocalState,State,SV1,WF),
951		opt_push_wait_flag_call_stack_info(WF,b_operator_call(member,[ElValue,b_operator(UnOP,[SV1])],Info),WF2),
952	?	unary_in_kernel_call(Module,Kernel_predicate,ElValue,SV1,WF2,Expression)
953		).
954		b_test_member_expression2(SetExpression,Type,Info,El,LocalState,State,WF) :-
955	?	b_compute_expression2(SetExpression,Type,Info,LocalState,State,SetValue,WF),
956		(always_well_defined_or_disprover_mode(El)
957		-> SetValue \== [] % if we have the empty set: check_element will always fail
958		; true % we could check SetValue \== [] if find_abort_values=false ??
959		),
960	?	b_compute_expression(El,LocalState,State,Element,WF),
961		Span = El, % Info is quite often the empty list
962		(not_invertible(El) % then no sense in setting up member constraint f(...) : SetValue ;
963		% we cannot used the info anyway; but we could enumerate
964		-> % we wait until Element is fully known before doing the check
965		ground_value_check(Element,GrEl),
966		when(nonvar(GrEl),kernel_call_predicate_check_element_of_wf(Element,SetValue,WF,Span))
967	?	; kernel_call_predicate_check_element_of_wf(Element,SetValue,WF,Span)).
968
969		:- use_module(external_functions,[external_fun_can_be_inverted/1]).
970		not_invertible(b(E,_,_)) :- not_inv_aux(E).
971		not_inv_aux(external_function_call(FunName,_Args)) :- \+ external_fun_can_be_inverted(FunName).
972		% TO DO: capture other cases like function applications
973		% TO DO: also do this in b_interpreter_check ?
974		% TO DO: We should compute this information in ast_cleanup; e.g., what if we do STRING_TO_INT(s)+1 : SET
975
976		% 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) ?
977
978		:- use_module(kernel_lists,[not_element_of_list_wf/3]).
979		b_test_notmember_expression(set_extension(Ex),El,_Set,_,LocalState,State,WF) :- !,
980		b_compute_expressions(Ex,LocalState,State,ExValueList,WF),
981		b_compute_expression(El,LocalState,State,ElementVal,WF),
982		not_element_of_list_wf(ElementVal,ExValueList,WF).
983		b_test_notmember_expression(SymbolicSetCst,El,_Set,_,LocalState,State,WF) :-
984		kernel_mappings:cst_not_in_boolean_type(SymbolicSetCst,Module:Kernel_predicate),!,
985		b_compute_expression(El,LocalState,State,ElValue,WF),
986		functor(KernelCall,Kernel_predicate,1),
987		arg(1,KernelCall,ElValue),
988		% debug_print(cst_not_in_boolean_type(9,KernelCall)),
989		kernel_call_predicate(KernelCall,Module,WF,SymbolicSetCst).
990		b_test_notmember_expression(Expression,El,_Set,Info,LocalState,State,WF) :-
991		functor(Expression,BOP,2),
992		kernel_mappings:binary_not_in_boolean_type(BOP,Module:Kernel_predicate),!,
993		b_compute_expression(El,LocalState,State,ElValue,WF),
994		\+ binary_in_definitely_true(BOP,ElValue),
995		arg(1,Expression,Arg1),arg(2,Expression,Arg2),
996		b_compute_expression(Arg1,LocalState,State,SV1,WF),
997		b_compute_expression(Arg2,LocalState,State,SV2,WF),
998		% KernelCall =.. [Kernel_predicate,ElValue,SV1,SV2,WF],
999		opt_push_wait_flag_call_stack_info(WF,b_operator_call(not_member,[ElValue,b_operator(BOP,[SV1,SV2])],Info),WF2),
1000	?	kernel_call_predicate3(Kernel_predicate,ElValue,SV1,SV2,Module,WF2,Expression).
1001		b_test_notmember_expression(Expression,El,_Set,Info,LocalState,State,WF) :-
1002		functor(Expression,UnOP,1),
1003		unary_not_in_boolean_type(UnOP,Module:Kernel_predicate),!,
1004		b_compute_expression(El,LocalState,State,ElValue,WF),
1005		\+ unary_in_definitely_true(UnOP,ElValue),
1006		arg(1,Expression,Arg1),
1007		b_compute_expression(Arg1,LocalState,State,SV1,WF),
1008		%KernelCall =.. [Kernel_predicate,ElValue,SV1,WF],
1009		%kernel_call_predicate(KernelCall,Module,WF,Expression).
1010		opt_push_wait_flag_call_stack_info(WF,b_operator_call(not_member,[ElValue,b_operator(UnOP,[SV1])],Info),WF2),
1011		kernel_call_predicate2(Kernel_predicate,ElValue,SV1,Module,WF2,Expression).
1012		b_test_notmember_expression(Expr,Elem,Set,_Info,LocalState,State,WF) :-
1013		(Expr=comprehension_set(Par,Cond)
1014		-> b_generate_closure_if_necessary(Par,Cond,LocalState,State,SetValue,WF) /* will not expand closure */
1015		; b_compute_expression(Set,LocalState,State,SetValue,WF)
1016		),
1017		(SetValue == []
1018		-> /* nothing can be member of empty set */
1019		check_well_defined(Elem,LocalState,State,WF)
1020		% we could disable this check if find_abort_values=true
1021		; b_compute_expression(Elem,LocalState,State,ElemValue,WF),
1022		%kernel_call_predicate2(not_element_of_wf,ElemValue,SetValue,kernel_objects,WF,Expr)
1023		%kernel_call_predicate(not_element_of_wf(ElemValue,SetValue,WF),kernel_objects,WF,Expr)
1024		kernel_call_predicate_not_element_of_wf(ElemValue,SetValue,WF)
1025		).
1026
1027		:- block block_test_implication(?,?,?,?,?,-).
1028		block_test_implication(LHS,RHS,LocalState,State,WF,_WF2) :-
1029	?	b_test_inner_boolean_expression(LHS,LocalState,State,WF),
1030		b_test_inner_boolean_expression(RHS,LocalState,State,WF).
1031		block_test_implication(LHS,_RHS,LocalState,State,WF,_WF2) :-
1032		b_not_test_inner_boolean_expression(LHS,LocalState,State,WF).
1033
1034
1035		b_test_equivalence(LHS,RHS,LocalState,State,WF,Ai,Ao) :-
1036		copy_wf_start(WF,equivalence,CWF),
1037	?	if(b_check_boolean_expression(LHS,LocalState,State,CWF,PredRes,Ai,Aii),
1038	?	(b_check_test_equivalence(PredRes,LHS,RHS,LocalState,State,CWF,Aii,Ao),
1039		copy_wf_finish(WF,CWF)),
1040		(% check LHS fails, We could check if RHS can be checked with b_check_boolean_expression
1041		Ai=Ao, get_binary_choice_wait_flag(equivalence,WF,WF2),
1042		b_enum_test_equivalence(LHS,RHS,LocalState,State,WF,WF2,Ai))).
1043		b_not_test_equivalence(LHS,RHS,LocalState,State,WF,Ai,Ao) :-
1044		copy_wf_start(WF,not_equivalence,CWF),
1045		if(b_check_boolean_expression(LHS,LocalState,State,CWF,PredRes,Ai,Aii),
1046		(negate(PredRes,NegPredRes), % from bool_pred
1047		b_check_test_equivalence(NegPredRes,LHS,RHS,LocalState,State,CWF,Aii,Ao),
1048		copy_wf_finish(WF,CWF)),
1049		(% check LHS fails, We could check if RHS can be checked with b_check_boolean_expression
1050		Ai=Ao, get_binary_choice_wait_flag(not_equivalence,WF,WF2),
1051		b_enum_not_test_equivalence(LHS,RHS,LocalState,State,WF,WF2,Ai))).
1052		b_check_test_equivalence(PredRes,LHS,RHS,LocalState,State,WF,Aii,Ao) :-
1053		% print('checking <=> '), print_bexpr(LHS), print(' '), print(PredRes),nl,
1054	?	(var(PredRes),b_check_boolean_expression(RHS,LocalState,State,WF,PredRes2,Aii,Ao) % TO DO <---- REPLACE CUT
1055		-> /* also propagate from right to left */
1056	?	equiv_bidrectional_test_boolean_expression(PredRes,PredRes2,LHS,RHS,LocalState,State,WF)
1057		; Aii=Ao,
1058	?	equiv_test_boolean_expression(PredRes,pred_true,RHS,LocalState,State,WF,Aii)
1059		). % should we also add a binary choice flag ?? what about a=2 <=> b/=3 ??
1060
1061		:- block b_enum_test_equivalence(?,?,?,?,?,-,?).
1062		b_enum_test_equivalence(LHS,RHS,LocalState,State,WF,_WF2,Ai) :-
1063		b_test_boolean_expression(LHS,LocalState,State,WF,Ai,Aii), % TO DO: we could call b_test_inner_boolean_expression with Ai
1064		b_test_boolean_expression(RHS,LocalState,State,WF,Aii,_).
1065		b_enum_test_equivalence(LHS,RHS,LocalState,State,WF,_WF2,Ai) :-
1066		b_not_test_boolean_expression(LHS,LocalState,State,WF,Ai,Aii),
1067		b_not_test_boolean_expression(RHS,LocalState,State,WF,Aii,_).
1068
1069		%enumerate_bool(X,WF) :- !.
1070		enumerate_bool(X,Prio,WF) :- (nonvar(X) -> true /* already set */
1071		; get_wait_flag0(WF,WF0),
1072		enumerate_bool0(X,Prio,WF,WF0)).
1073
1074		:- block enumerate_bool0(?,?,?,-).
1075		enumerate_bool0(X,Prio,WF,_) :- (nonvar(X) -> true /* already set */
1076		; %print(enum_bool(X)), translate:print_bexpr(LHS),nl,
1077		% get_binary_choice_wait_flag(enumerate_bool,WF,WF2),
1078		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
1079		enumerate_bool_aux(X,WF2)).
1080		:- block enumerate_bool_aux(-,-).
1081		%enumerate_bool_aux(P,WF) :- var(P),print(forcing_bool(P,WF)),nl,fail. %
1082		enumerate_bool_aux(pred_true,_).
1083		enumerate_bool_aux(pred_false,_).
1084
1085		:- block b_test_disjunction(?,?,?,?,?,-,?).
1086		b_test_disjunction(LHS,_RHS,LocalState,State,WF,_WF2,Ai) :-
1087	?	b_test_boolean_expression(LHS,LocalState,State,WF,Ai,_).
1088		b_test_disjunction(LHS,RHS,LocalState,State,WF,_WF2,Ai) :-
1089	?	b_not_test_boolean_expression(LHS,LocalState,State,WF,Ai,Aii),
1090	?	b_test_boolean_expression(RHS,LocalState,State,WF,Aii,_).
1091
1092		:- block b_not_test_conjunction(?,?,?,?,?,-,?).
1093		b_not_test_conjunction(LHS,_RHS,LocalState,State,WF,_WF2,Ai) :-
1094	?	b_not_test_boolean_expression(LHS,LocalState,State,WF,Ai,_).
1095		b_not_test_conjunction(LHS,RHS,LocalState,State,WF,_WF2,Ai) :-
1096	?	b_test_boolean_expression(LHS,LocalState,State,WF,Ai,Aii),
1097	?	b_not_test_boolean_expression(RHS,LocalState,State,WF,Aii,_).
1098
1099		:- block b_enum_not_test_equivalence(?,?,?,?,?,-,?).
1100		b_enum_not_test_equivalence(LHS,RHS,LocalState,State,WF,_WF2,Ai) :-
1101		b_test_boolean_expression(LHS,LocalState,State,WF,Ai,Aii), % we could call b_test_inner_boolean_expression with Ai
1102		b_not_test_boolean_expression(RHS,LocalState,State,WF,Aii,_).
1103		b_enum_not_test_equivalence(LHS,RHS,LocalState,State,WF,_WF2,Ai) :-
1104		b_not_test_boolean_expression(LHS,LocalState,State,WF,Ai,Aii),
1105		b_test_boolean_expression(RHS,LocalState,State,WF,Aii,_).
1106
1107
1108
1109		/* --------------------------------------*/
1110		/* b_not_test_boolean_expression */
1111		/* --------------------------------------*/
1112
1113		b_not_test_list_of_boolean_expression([],_,_,_WF).
1114		b_not_test_list_of_boolean_expression([B1|T],LS,S,WF) :-
1115		b_not_test_boolean_expression(B1,LS,S,WF),
1116		b_not_test_list_of_boolean_expression(T,LS,S,WF).
1117
1118		:- assert_pre(b_interpreter:b_not_test_boolean_expression_cs(E,LS,S,_,_),
1119		(bsyntaxtree:check_if_typed_predicate(E),type_check(LS,store),type_check(S,store))).
1120		:- assert_post(b_interpreter:b_not_test_boolean_expression_cs(_,_,_,_,_), true).
1121
1122
1123		% a version where we can provide an initial call stack entry for context
1124		b_not_test_boolean_expression_cs(E,LS,S,PredKind,Nr) :-
1125		init_wait_flags_cs(E,PredKind,Nr,b_not_test_boolean_expression_cs,WF), % TODO: we could register negation info
1126		% TO DO: call b_trace_test_components ?
1127	?	b_not_test_boolean_expression(E,LS,S,WF),
1128		ground_wait_flags(WF).
1129
1130		b_not_test_boolean_expression(E,LS,S,WF) :-
1131	?	empty_avl(Ai), b_not_test_boolean_expression(E,LS,S,WF,Ai,_).
1132
1133		:- assert_pre(b_interpreter:b_not_test_boolean_expression(E,LS,S,WF),
1134		(type_check(E,boolean_expression),type_check(LS,store),type_check(S,store), type_check(WF,wait_flag))).
1135		:- assert_post(b_interpreter:b_not_test_boolean_expression(_,_,_,_), true).
1136
1137		:- if(environ(prob_debug_watch_flag,true)).
1138		b_not_test_boolean_expression(b(Expr,_,Infos),LS,S,WF,Ai,Ao) :- !,
1139		(waitflag0_is_set(WF)
1140		-> debug:watch(400,b_interpreter:b_not_test_boolean_expression2(Expr,Infos,LS,S,WF,Ai,Ao))
1141		; debug:watch_det(400,b_interpreter:b_not_test_boolean_expression2(Expr,Infos,LS,S,WF,Ai,Ao)) ).
1142		:- else.
1143		b_not_test_boolean_expression(b(Expr,Type,Infos),LS,S,WF,Ai,Ao) :- !,
1144		(preference(smt_supported_interpreter,true)
1145		-> b_not_test_boolean_expression2(Expr,Infos,LS,S,WF,Ai,Ao),create_negation(b(Expr,Type,Infos),Neg),
1146		get_wait_flag1(smt_call,WF,BeforeEnumWF),
1147		gensym:gensym(smt_assertion_name,Symbol),
1148		smt_add_predicate(BeforeEnumWF,Neg,LS,S,Symbol)
1149	?	; b_not_test_boolean_expression2(Expr,Infos,LS,S,WF,Ai,Ao)).
1150		:- endif.
1151		b_not_test_boolean_expression(E,LS,S,WF,Ai,Ao) :-
1152		add_internal_error('Boolean (not) expression not properly wrapped: ',
1153		b_not_test_boolean_expression(E,LS,S,WF,Ai,Ao)),
1154		b_not_test_boolean_expression2(E,[],LS,S,WF,Ai,Ao).
1155
1156		b_not_test_boolean_expression2(truth,_,_,_,_WF,_Ai,_Ao) :- !,fail.
1157		b_not_test_boolean_expression2(falsity,_,_,_,_WF,Ai,Ao) :- !,Ai=Ao. % NOT COVERED (2)
1158		b_not_test_boolean_expression2(negation(BExpr),_,LocalState,State,WF,Ai,Ao) :- !,
1159		b_test_boolean_expression(BExpr,LocalState,State,WF,Ai,Ao).
1160		% following makes test 349 fail:
1161		%b_not_test_boolean_expression2(conjunct(LHS,RHS),Infos,LocalState,State,WF,Ai,Ao) :- !,
1162		% nl, print(' NOT: '),translate:print_bexpr(b(conjunct(LHS,RHS),pred,Infos)),nl,
1163		% create_negation(LHS,NegLHS), % TO DO: avoid this construction by generalising code for disjunct
1164		% create_negation(RHS,NegRHS),
1165		% b_test_boolean_expression2(disjunct(NegLHS,NegRHS),Infos,LocalState,State,WF,Ai,Ao).
1166		b_not_test_boolean_expression2(conjunct(LHS,RHS),Infos,LocalState,State,WF,Ai,Ao) :- !,
1167		b(conjunct(LHS,RHS),pred,Infos) = Conj,
1168		copy_wf_start(WF,not_conjunct,CWF),
1169	?	if(b_check_boolean_expression(Conj,LocalState,State,CWF,PredRes,Ai,Ao),
1170		(PredRes=pred_false,
1171	?	copy_wf_finish(WF,CWF)
1172		),
1173	?	if(b_check_boolean_expression(LHS,LocalState,State,CWF,LHSPredRes,Ai,Ao), % some redundant work with call above: TODO: avoid !
1174		(copy_wf_finish(WF,CWF),
1175		get_last_wait_flag(not_conjunct_rhs,WF,WF2), % before starting to enumerate infinite types: better try both possibilities:
1176		b_not_test_conjunction_rhs(LHSPredRes,RHS,LocalState,State,WF,Ai,WF2)
1177		),
1178		(Ai=Ao,
1179		get_priority_of_boolean_expression2(disjunct(LHS,RHS),StartPrio),
1180		%get_wait_flag(Prio,not_conjunct,WF,WF2),
1181		get_binary_choice_wait_flag_exp_backoff(StartPrio,not_conjunct,WF,WF2),
1182		% TO DO: we could check if LHS or RHS are registered in Ai as pred_true/pred_false ??
1183		b_not_test_conjunction(LHS,RHS,LocalState,State,WF,WF2,Ai))
1184		)
1185		).
1186
1187		b_not_test_boolean_expression2(implication(LHS,RHS),_,LocalState,State,WF,Ai,Ao) :- !,
1188		b_test_boolean_expression(LHS,LocalState,State,WF,Ai,Aii),
1189		b_not_test_boolean_expression(RHS,LocalState,State,WF,Aii,Ao).
1190		b_not_test_boolean_expression2(equivalence(LHS,RHS),_,LocalState,State,WF,Ai,Ao) :- !,
1191		b_not_test_equivalence(LHS,RHS,LocalState,State,WF,Ai,Ao).
1192		b_not_test_boolean_expression2(disjunct(LHS,RHS),_,LocalState,State,WF,Ai,Ao) :- !,
1193		b_not_test_boolean_expression(LHS,LocalState,State,WF,Ai,Aii),
1194		b_not_test_boolean_expression(RHS,LocalState,State,WF,Aii,Ao).
1195		b_not_test_boolean_expression2(lazy_let_pred(Id,AssignmentExpr,Expr),_I,LocalState,State,WF,Ai,Ao) :- !,
1196		add_lazy_let_id_and_expression(Id,AssignmentExpr,LocalState,State,NewLocalState,WF,Ai),
1197		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
1198		b_not_test_boolean_expression2(lazy_lookup_pred(Id),_Info,LocalState,_State,WF,Ai,Ao) :- !, Ai=Ao,
1199		lookup_value_for_existing_id_wf(Id,LocalState,(Trigger,Value),WF), % should normally only occur in LocalState; value introduced by lazy_let
1200		(Trigger,Value) = (pred_true,pred_false). % force evaluation
1201		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
1202		is_pred_false(PredVal),Ai=Ao.
1203		b_not_test_boolean_expression2(Expr,Info,LocalState,State,WF,Ai,Ao) :-
1204		% TO DO: we could put some of the operators into the Ai store (comparison operators)
1205	?	b_not_test_atomic_boolean_expression2(Expr,Info,LocalState,State,WF,Ai,Ao).
1206
1207		% Other boolean expressions, not involving boolean connectives
1208		b_not_test_atomic_boolean_expression2(exists(Parameters,RHS),Infos,LocalState,State,WF,Ai,Ao) :- !,
1209		/* #ID.(RHS) */
1210		Ai=Ao,
1211	?	b_not_test_exists(Parameters,RHS,Infos,LocalState,State,compile,WF).
1212		b_not_test_atomic_boolean_expression2(forall(Parameters,LHS,RHS),Infos,LocalState,State,WF,Ai,Ao) :- !,
1213		/* !ID.(LHS => RHS) */
1214		Ai=Ao,
1215		safe_create_texpr(negation(RHS),pred,Negation),
1216		conjunct_predicates_with_pos_info(LHS,Negation,Condition),
1217		% conjunct_predicates merges the used_ids Info in Condition
1218	?	b_test_exists(Parameters,Condition,Infos,LocalState,State,WF).
1219		/* TODO(DP, 2.8.2008): Extension for Z: a let-statement as predicate */
1220		b_not_test_atomic_boolean_expression2(let_predicate(Ids,AssignmentExprs,Pred),Infos,LocalState,State,WF,Ai,Ao) :-
1221		!,Ai=Ao, % any expression inside the LET cannot be safely reused
1222	?	set_up_localstate_for_let(Ids,ParaValues,AssignmentExprs,LocalState,State,LetState,WF),
1223		opt_push_wait_flag_call_stack_quantifier_info(WF,let_quantifier,Ids,ParaValues,Infos,WF2),
1224	?	b_not_test_boolean_expression(Pred,LetState,State,WF2). % NOT COVERED (10)
1225		/* TODO(DP, 2.8.2008): */
1226		b_not_test_atomic_boolean_expression2(freetype_case(Freetype,Case,Expr),_,LocalState,State,WF,Ai,Ao) :-
1227		!,Ai=Ao,b_compute_expression(Expr,LocalState,State,freeval(Freetype,RealCase,_),WF),
1228		dif(RealCase,Case). % NOT COVERED (11)
1229		b_not_test_atomic_boolean_expression2(finite(SetExpr),_,LocalState,State,WF,Ai,Ao) :-
1230		!, Ai=Ao,b_compute_expression(SetExpr,LocalState,State,Value,WF),
1231		kernel_call_predicate(is_infinite_set_wf(Value,WF),kernel_objects,WF,finite(SetExpr)).
1232		/* Extension for Kodkod */
1233		b_not_test_atomic_boolean_expression2(kodkod(ProblemId,_),_,LocalState,State,WF,Ai,Ao) :-
1234		!,Ai=Ao,get_wait_flag1(kodkod_negative_call,WF,WF0),
1235		kodkod_request(ProblemId,neg,LocalState,State,WF0). % NOT COVERED (12)
1236		b_not_test_atomic_boolean_expression2(partition(LHS,RHS),Info,LocalState,State,WF,Ai,Ao) :- !,
1237		b_interpreter_check:register_predicate(partition(LHS,RHS),Info,pred_false,Reused,Ai,Ao),
1238		(Reused==true -> true
1239		; b_compute_expression(LHS,LocalState,State,SV1,WF),
1240		l_compute_expression(RHS,LocalState,State,SV2,WF), % RHS is Prolog list of expressions
1241		kernel_call_predicate(not_partition_wf(SV1,SV2,WF),kernel_objects,WF,partition(LHS,RHS))
1242		).
1243		b_not_test_atomic_boolean_expression2(external_pred_call(FunName,Args),Info,LocalState,State,WF,Ai,Ao) :-
1244		!, Ai=Ao,
1245		(do_not_evaluate_args(FunName) -> EvaluatedArgs=[]
1246		; b_compute_expressions(Args, LocalState,State, EvaluatedArgs, WF)),
1247		push_wait_flag_call_stack_info(WF,external_call(FunName,EvaluatedArgs,Info),WF2),
1248		call_external_predicate(FunName,Args,EvaluatedArgs,LocalState,State,pred_false,Info,WF2).
1249		b_not_test_atomic_boolean_expression2(Pred,Info,LocalState,State,WF,Ai,Ao) :-
1250		b_interpreter_check:register_predicate(Pred,Info,pred_false,Reused,Ai,Ao),
1251		(Reused==true
1252		-> %% print('REUSED (not): '), translate:print_bexpr(Pred),nl,
1253		true
1254	?	; b_not_test_atomic_boolean_expression3(Pred,Info,LocalState,State,WF)).
1255		b_not_test_atomic_boolean_expression3(Expression,Info,LocalState,State,WF) :-
1256		functor(Expression,BOP,2),
1257	?	kernel_mappings:negate_binary_boolean_operator(BOP,NBOP),
1258		arg(1,Expression,Arg1),arg(2,Expression,Arg2),!,
1259		NExpression =.. [NBOP,Arg1,Arg2],
1260	?	b_test_atomic_boolean_expression2(NExpression,Info,LocalState,State,WF).
1261		b_not_test_atomic_boolean_expression3(Expression,Info,LocalState,State,WF) :-
1262		functor(Expression,BOP,2),
1263		kernel_mappings:negate_binary_boolean_operator_swap(BOP,NBOP),
1264		arg(1,Expression,Arg1),arg(2,Expression,Arg2),!,
1265		NExpression =.. [NBOP,Arg2,Arg1],
1266		b_test_atomic_boolean_expression2(NExpression,Info,LocalState,State,WF).
1267		b_not_test_atomic_boolean_expression3(E,_,_,_,_WF) :-
1268		add_internal_error('Uncovered boolean expression (not): ',E),
1269		print_functor(E),nl,fail.
1270
1271
1272		% test RHS of not-conjunction depending on outcome of LHS
1273		:- block b_not_test_conjunction_rhs(-,?,?,?,?,?,-).
1274		b_not_test_conjunction_rhs(pred_false,_RHS,_LocalState,_State,_WF,_Ai,_LWF).
1275		b_not_test_conjunction_rhs(pred_true,RHS,LocalState,State,WF,Ai,_LWF) :-
1276	?	b_not_test_boolean_expression(RHS,LocalState,State,WF,Ai,_).
1277
1278		/* -----------------------------*/
1279		/* b_compute_expression */
1280		/* -----------------------------*/
1281
1282
1283
1284		:- assert_must_succeed((b_interpreter:b_compute_expression(b(pow_subset(
1285		b(identifier(nm),set(integer),[])),set(set(integer)),[]),
1286		[], [bind(nm,[])],R,_WF),
1287		nonvar(R), custom_explicit_sets:expand_custom_set_to_list(R,[[]]))).
1288		:- assert_must_succeed((b_interpreter:b_compute_expression(b(pow_subset(
1289		b(identifier(nm),set(boolean),[])),set(set(boolean)),[]),[],
1290		[bind(nm,[pred_false /* bool_false */])],R,_WF),
1291		nonvar(R), custom_explicit_sets:expand_custom_set_to_list(R,ER),
1292		kernel_objects:equal_object(ER,[[pred_false /* bool_false */],[]]))).
1293
1294		:- assert_pre(b_interpreter:b_compute_expression(Exp,LS,State,_Val,WF),
1295		(nonvar(Exp),
1296		bsyntaxtree:check_if_typed_expression(Exp),
1297		type_check(LS,store),type_check(State,store), type_check(WF,wait_flag))).
1298		:- assert_post(b_interpreter:b_compute_expression(_E,_LS,_State,Val,WF),
1299		(b_interpreter:value_type(Val), type_check(WF,wait_flag))). %, nonvar(Val)
1300
1301		b_compute_expression_nowf(E,LS,S,R) :-
1302		b_compute_expression_nowf(E,LS,S,R,none,0).
1303
1304		b_compute_expression_nowf(E,LS,S,R,FormulaKind,Nr) :-
1305		get_texpr_info(E,Info),
1306	?	b_compute_expression_nowf(E,LS,S,R,FormulaKind,Nr,Info).
1307		b_compute_expression_nowf(E,LS,S,R,FormulaKind,Nr,Span) :-
1308	?	b_compute_expression_no_wf8(E,LS,S,R,FormulaKind,Nr,default,Span).
1309		% a variation where we tell ProB to expect non-symbolic / explicit values
1310		b_compute_explicit_epression_no_wf(E,LS,S,R,FormulaKind,Nr) :-
1311		get_texpr_info(E,Info),
1312	?	b_compute_explicit_epression_no_wf(E,LS,S,R,FormulaKind,Nr,Info).
1313		b_compute_explicit_epression_no_wf(E,LS,S,R,FormulaKind,Nr,Span) :-
1314	?	b_compute_expression_no_wf8(E,LS,S,R,FormulaKind,Nr,expect_explicit_value,Span).
1315		b_compute_expression_no_wf8(E,LS,S,R,FormulaKind,Nr,Expect,Span) :-
1316		%add_message(b_compute_expression,'Called Version wo WFLAGS: ', b_compute_expression(E,LS,S,R)),
1317		(Expect=expect_explicit_value -> WFInfos = [expect_explicit_value] ; WFInfos = []),
1318		(FormulaKind = none -> init_wait_flags(WF,WFInfos)
1319		; CallStackEntry = prob_command_context(eval_expr_command(FormulaKind,Nr),Span),
1320		init_wait_flags_and_push_call_stack(no_wf_available,CallStackEntry,WFInfos,WF)
1321		),
1322	?	b_compute_expression(E,LS,S,R,WF),
1323	?	ground_wait_flags(WF), % this will add abort errors and fail before enumerating the result:
1324		init_wait_flags(WF2,[b_compute_expression_nowf2]),
1325		get_texpr_type(E,Type),
1326		b_enumerate:b_tighter_enumerate_single_value(R,Type,Span,b_compute_expression_nowf,WF2), %should rarely be necessary
1327		% a non-ground result only occurs when WD error appears and in this case ground_wait_flags will fail after
1328		% adding the abort error (and thus no value is returned)
1329		% exceptions are test 1066 with a complicated set comprehension used in a function application
1330		% test 1861 relies on two phase enumeration
1331		ground_wait_flags(WF2).
1332
1333		l_compute_expression([],_LS,_S,[],_WF).
1334		l_compute_expression([H|T],LS,S,[CH|CT],WF) :-
1335		b_compute_expression(H,LS,S,CH,WF),
1336		l_compute_expression(T,LS,S,CT,WF).
1337
1338		:- if(environ(prob_debug_watch_flag,true)).
1339		b_compute_expressiond(b(Expr,Type,Info),LS,S,R,WF) :- !,
1340		((ground(Type), Type \== pred, Type \== subst) -> true
1341		; add_error_wf(b_compute_expression,'Expression has illegal type: ',b(Expr,Type,Info),WF)),
1342		check_value(R,b(Expr,Type,Info)),
1343		b_compute_expression2(Expr,Type,Info,LS,S,R,WF).
1344		:- block check_value(-,?).
1345		check_value(pred_true,_) :- !. check_value(pred_false,_) :- !.
1346		check_value(string(_),_) :- !.
1347		check_value([],_) :- !.
1348		check_value([H|T],E) :- !, check_value(H,E), check_value(T,E).
1349		check_value((A,B),E) :- !, check_value(A,E), check_value(B,E).
1350		check_value(fd(N,T),E) :- !, (nonvar(T) -> check_fd(N,T,E) ; check_err(fd(N,T),E)).
1351		check_value(global_set(GS),E) :- !,(nonvar(GS) -> true ; check_err(global_set(GS),E)).
1352		check_value(avl_set(AS),E) :- !,((nonvar(AS),AS=node(_,_,_,_,_)) -> true ; check_err(global_set(AS),E)).
1353		check_value(int(X),E) :- !,check_int(X,E).
1354		check_value(closure(P,T,B),E) :- !,
1355		(ground(P),ground(T),nonvar(B)
1356		-> (same_length(P,T) -> bsyntaxtree:check_ast(B) ; check_err(closure_not_same_length(P,T)))
1357		; check_err(closure(P,T,B),E)).
1358		check_value(rec(_),_) :- !. %TODO: check
1359		check_value(X,E) :- check_err(uncovered(X),E).
1360		% TO DO: add records + more thorough checking of global_set and closures and avl_sets
1361		:- block check_int(-,?).
1362		check_int(X,E) :- (number(X) -> true ; check_err(int(X),E)).
1363		:- block check_fd(-,?,?).
1364		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)).
1365
1366		check_err(V,E) :- add_internal_error('Illegal value when computing expression: ',V:E).
1367		b_compute_expression(E,LS,S,R,WF) :- !,
1368		(waitflag0_is_set(WF)
1369		-> debug:watch(100,b_interpreter:b_compute_expressiond(E,LS,S,R,WF))
1370		; debug:watch_det(100,b_interpreter:b_compute_expressiond(E,LS,S,R,WF))).
1371		:- else.
1372		b_compute_expression(b(Expr,Type,Info),LS,S,R,WF) :- !,
1373		((ground(Type), Type \== pred, Type \== subst) -> true
1374		; Type==pred -> add_internal_error_wf(b_interpreter,'Expected expression, not predicate: ',b(Expr,Type,Info),Info,WF)
1375		; Type==subst -> add_internal_error_wf(b_interpreter,'Expected expression, not substitution: ',b(Expr,Type,Info),Info,WF)
1376		; add_internal_error_wf(b_interpreter,'Expression has non-ground type: ',b(Expr,Type,Info),Info,WF)
1377		),
1378	?	b_compute_expression2(Expr,Type,Info,LS,S,R,WF).
1379		:- endif.
1380		b_compute_expression(Expr,LS,S,R,WF) :-
1381		add_internal_error('Expression not properly wrapped: ',b_compute_expression(Expr,LS,S,R,WF)),
1382		b_compute_expression2(Expr,unknown,[],LS,S,R,WF).
1383
1384
1385		:- use_module(bsyntaxtree,[get_texpr_set_type/2]).
1386
1387		%:- use_module(b_global_sets,[b_type2_set/2]).
1388		%b_compute_expression2(V,T,I,LS,S,R,_WF) :- nonvar(R), print('result_instantiated: '(R:V)),nl,fail.
1389	?	b_compute_expression2(value(Val),_T,_I,_LS,_S,V,WF) :- !, equal_object_wf(Val,V,WF). %Val=V.
1390		b_compute_expression2(boolean_true,_T,_I,_LState,_State,Res,_WF) :- !, Res = pred_true /* bool_true */. % for simple types we can use ordinary unification
1391		b_compute_expression2(boolean_false,_T,_I,_LState,_State,Res,_WF) :- !, Res = pred_false /* bool_false */.
1392		b_compute_expression2(integer_set(NSET),_T,_I,_LState,_State,Res,WF) :- !, equal_object_wf(Res,global_set(NSET),WF). %Res = global_set(NSET).
1393		b_compute_expression2(bool_set,_T,_I,_LState,_State,Res,WF) :- !, % b_type2_set(bool,Res).
1394		equal_object_wf(Res,avl_set(node(pred_false,true,1,empty,node(pred_true,true,0,empty,empty))),WF).
1395		% 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
1396		b_compute_expression2(float_set,_T,_I,_LState,_State,Res,WF) :- !, equal_object_wf(Res,global_set('FLOAT'),WF).
1397		b_compute_expression2(real_set,_T,_I,_LState,_State,Res,WF) :- !, equal_object_wf(Res,global_set('REAL'),WF).
1398		b_compute_expression2(string_set,_T,_I,_LState,_State,Res,WF) :- !, equal_object_wf(Res,global_set('STRING'),WF).
1399		% was all_strings(Res). %% NOT COVERED (6)
1400		b_compute_expression2(string(S),_T,_I,_LState,_State,Res,_WF) :- !,
1401		% TODO(ML,26.8.2008): Check if we should use a different functor for syntax tree vs data
1402		Res = string(S).
1403		b_compute_expression2(typeset,Type,_I,_LState,_State,Res,WF) :- !,
1404		is_set_type(Type,ElType), % we could generate global_set('STRING'),... for certain types
1405		equal_object_wf(Res,closure('_zzzz_unary',[ElType],b(truth,pred,[])),WF).
1406		b_compute_expression2(empty_set,_T,_I,_LState,_State,Res,_WF) :- !, empty_set(Res).
1407		b_compute_expression2(empty_sequence,_T,_I,_LState,_State,Res,_WF) :- !, empty_sequence(Res).
1408		b_compute_expression2(event_b_identity,EType,_I,_LState,_State,Res,WF) :-
1409		get_set_type(EType,couple(Type,Type)),!,
1410		event_b_identity_for_type(Type,Res,WF).
1411		b_compute_expression2(integer(Val),_T,_I,_LocalState,_State,Res,_WF) :- !, Res = int(Val).
1412		b_compute_expression2(max_int,_T,_I,_LS,_S,Res,_WF) :-
1413		preferences:get_preference(maxint,CVal),!, Res = int(CVal).
1414		b_compute_expression2(min_int,_T,_I,_LS,_S,Res,_WF) :-
1415		preferences:get_preference(minint,CVal),!, Res = int(CVal).
1416		b_compute_expression2(identifier(Id),Type,Info,LocalState,State,Res,WF) :- !,
1417		lookup_value_in_store_and_global_sets_wf(Id,Type,LocalState,State,Value,Info,WF),
1418		equal_object_wf(Res,Value,WF).
1419		b_compute_expression2(lazy_lookup_expr(Id),_Type,_Info,LocalState,_State,Res,WF) :- !,
1420		lookup_value_for_existing_id_wf(Id,LocalState,(Trigger,Value),WF), % should normally only occur in LocalState; value introduced by lazy_let
1421		Trigger = pred_true, % force evaluation
1422		equal_object_wf(Res,Value,WF).
1423		b_compute_expression2(lazy_let_expr(Id,AssignmentExpr,Expr),_T,_I,LocalState,State,Value,WF) :-
1424		!,
1425		add_lazy_let_id_and_expression(Id,AssignmentExpr,LocalState,State,NewLocalState,WF),
1426		%Trigger = pred_true, % expressions cannot be delayed !? (TO DO: more refined check)
1427		%block_lazy_compute_expression(Trigger,_,AssignmentExpr,LocalState,State,IdValue,WF,Ai),
1428		b_compute_expression(Expr,NewLocalState,State,Value,WF).
1429		b_compute_expression2(real(Atom),_T,_I,_LocalState,_State,Res,_WF) :- !, construct_real(Atom,Res).
1430		b_compute_expression2(rec(Fields),_T,_I,LocalState,State,Record,WF) :- !,
1431	?	l_compute_field(Fields,LocalState,State,FieldValues,WF),
1432	?	construct_record_wf(FieldValues,Record,WF).
1433		b_compute_expression2(record_field(RecEx,Name),_T,_I,LocalState,State,Value,WF) :- !,
1434	?	b_compute_expression(RecEx,LocalState,State,RecValue,WF),
1435		access_record_wf(RecValue,Name,Value,WF).
1436		b_compute_expression2(freetype_set(Id),_T,_I,_LState,_State,Val,_WF) :- !, Val=freetype(Id). %% NOT COVERED (17)
1437		b_compute_expression2(function(Function,FunArg),Type,Info,LocalState,State,Res,WF) :- !,
1438	?	b_compute_expression_function(Function,FunArg,Type,Info,LocalState,State,Res,WF).
1439		b_compute_expression2(card(b(Arg1,Type,Info)),integer,OuterInfo,LocalState,State,Card,WF) :- !,
1440	?	b_compute_card(Arg1,Type,Info,OuterInfo,LocalState,State,Card,WF).
1441		b_compute_expression2(max(b(Arg1,Type,Info)),integer,_I,LocalState,State,Max,WF) :- !,
1442		b_compute_max(Arg1,Type,Info,LocalState,State,Max,WF).
1443		b_compute_expression2(min(b(Arg1,Type,Info)),integer,_I,LocalState,State,Min,WF) :- !,
1444		b_compute_min(Arg1,Type,Info,LocalState,State,Min,WF).
1445		b_compute_expression2(set_extension(Ex),Type,_I,LocalState,State,Res,WF) :- !,
1446	?	b_compute_expressions(Ex,LocalState,State,ExValue,WF),
1447		kernel_call(b_interpreter:convert_list_of_expressions_into_set_wf(ExValue,ValueSet,Type,WF),ExValue,WF, set_extension(Ex)),
1448	?	equal_object_wf(Res,ValueSet,WF).
1449		%kernel_call_convert_list_of_expressions_into_set_wf(ExValue,ValueSet,Type, WF).
1450		%b_compute_expression('ListTermes'(ListOfEx),LocalState,State,ValueSet,WF) :- !,
1451		% /* convert list of expressions of CASE statement into set of elements */
1452		% b_compute_expression(ListOfEx,LocalState,State,Value,WF),
1453		% init_wait_flags(WF),convert_list_of_expressions_into_set_wf(Value,ValueSet,set(any),WF),ground_wait_flags(WF).
1454		b_compute_expression2(sequence_extension(Ex),_T,_I,LocalState,State,ValueSeq,WF) :- !,
1455	?	b_compute_expressions(Ex,LocalState,State,Value,WF),
1456		kernel_call(b_interpreter:convert_list_of_expressions_into_sequence(Value,ValueSeq),Value,WF,sequence_extension(Ex)).
1457		b_compute_expression2(convert_bool(PRED),_T,_I,LocalState,State,Val,WF) :- !, /* B bool(.) operator */
1458		b_convert_bool(PRED,LocalState,State,WF,Val).
1459		b_compute_expression2(couple(El1,El2),_T,_I,LocalState,State,Result,WF) :- !, Result = (Val1,Val2),
1460	?	b_compute_expression(El1,LocalState,State,Val1,WF),
1461	?	b_compute_expression(El2,LocalState,State,Val2,WF).
1462		b_compute_expression2(comprehension_set(Parameters,Condition),_T,Info,LocalState,State,Result,WF) :- !,
1463	?	b_compute_comprehension_set(Parameters,Condition,Info,LocalState,State,Result,WF).
1464		b_compute_expression2(recursive_let(TId,TSet),OrigType,OrigInfo,LocalState,State,Result,WF) :- !,
1465		% LET TId = TSet in TSet
1466		( get_texpr_expr(TSet,comprehension_set(Parameters,Condition)) ->
1467		true % if the argument TSet is a comprehension set,
1468		% we just add a recursive parameter
1469		; get_texpr_set_type(TSet,Type) ->
1470		% if not, we construct a new comprehension set {x | x:TSet}
1471		unique_typed_id("_tmparg_",Type,TArg),
1472		Parameters=[TArg],
1473		safe_create_texpr(member(TArg,TSet),pred,Condition)
1474		;
1475		add_internal_error('Expected set as argument to recursive_let',
1476		b_compute_expression2(recursive_let(TId,TSet),OrigType,OrigInfo,LocalState,State,Result,WF)),fail
1477		),
1478		% Generate closure where the references to the recursion are kept
1479		% add recursion ID to parameters to prevent removal of references during compilation
1480		generate_recursive_closure(TId,recursion,[TId|Parameters],Condition,LocalState,State,Closure1,WF),
1481		% add_message(b_interpreter,'Recursive Let for: ',TId,TId),
1482		% remove recursion ID from parameters after compilation
1483		Closure1=closure([_|P],[_|T],Cond),RClosure=closure(P,T,Cond),
1484		% Generate closure where the references to the recursion are kept
1485		generate_recursive_closure(TId,RClosure,Parameters,Condition,LocalState,State,Result,WF).
1486		b_compute_expression2(general_sum(Ids,Condition,Expression),Type,Info,LocalState,State,SumResult,WF) :- !,
1487		b_general_sum_or_mul(Ids,Condition,Expression,Type,Info,LocalState,State,SumResult,WF,sum).
1488		b_compute_expression2(general_product(Ids,Condition,Expression),Type,Info,LocalState,State,MulResult,WF) :- !,
1489		b_general_sum_or_mul(Ids,Condition,Expression,Type,Info,LocalState,State,MulResult,WF,mul).
1490		/* Begin: Extensions for Z */
1491		b_compute_expression2(if_then_else(If,Then,Else),T,_I,LocalState,State,Value,WF) :- !,
1492		opt_push_wait_flag_call_stack_info(WF,b_expr_call(if_test,If),WF2),
1493	?	b_try_check_boolean_expression_wf(If,LocalState,State,WF2,PredRes),
1494		(var(PredRes), can_get_full_fd_value(T), preferences:preference(use_clpfd_solver,true),
1495		always_well_defined(Then), always_well_defined(Else)
1496		% Note: always_well_defined_or_disprover_mode probably not ok, as we evaluate the expressions unconditionally
1497		-> b_clpfd_if_then_else(PredRes,T,Then,Else,LocalState,State,Value,WF)
1498	?	; b_compute_if_then_else(PredRes,Then,Else,LocalState,State,Value,WF)
1499		).
1500		b_compute_expression2(let_expression_global(Ids,AssignmentExprs,Expr),_T,Info,LocalState,State,Value,WF) :-
1501		debug_println(4,global_let(Ids,Info)),
1502		% store variables globally (not in LocalState) to be visible to subsidiary operation_calls
1503		!, set_up_localstate_for_global_let(Ids,AssignmentExprs,LocalState,State,LetState,WF),
1504		b_compute_expression(Expr,LocalState,LetState,Value,WF).
1505		b_compute_expression2(let_expression(Ids,AssignmentExprs,Expr),_T,_I,LocalState,State,Value,WF) :-
1506	?	!, set_up_localstate_for_let(Ids,_ParaValues,AssignmentExprs,LocalState,State,LetState,WF),
1507	?	b_compute_expression(Expr,LetState,State,Value,WF). %% NOT COVERED (30)
1508		b_compute_expression2(freetype_constructor(Id,Case,Expr),_T,_I,LocalState,State,FreeValue,WF) :-
1509		!, FreeValue = freeval(Id,Case,Value),
1510		b_compute_expression(Expr,LocalState,State,Value,WF). %% NOT COVERED (32)
1511		b_compute_expression2(freetype_destructor(Id,Case,Expr),_T,Info,LocalState,State,Value,WF) :-
1512		!, b_compute_expression(Expr,LocalState,State,freeval(Id,VCase,VValue),WF),
1513		check_freetype_case(Id,Case,VCase,VValue,Value,Info,WF).
1514		/* End: Extensions for Z */
1515		b_compute_expression2(assertion_expression(Cond,ErrMsg,Expr),T,Info,LocalState,State,Value,WF) :- !,
1516		opt_push_wait_flag_call_stack_info(WF,
1517		span_predicate(b(assertion_expression(Cond,ErrMsg,b(value(string('')),string,[])),T,Info),LocalState,State),WF2),
1518		% should we use another term for call stack?
1519		(get_preference(disprover_mode,true) -> PredRes = pred_true ; true), % in Disprover mode we know Cond must be true
1520		b_try_check_boolean_expression_no_enum_wf(Cond,LocalState,State,WF2,PredRes), % DO NOT ENUM, unless we cannot reify
1521		% does not make sense to enumerate PredRes as with pred_false we get no value anyway
1522		% however, we may get pending co-routines if Cond cannot be reified
1523		( PredRes==pred_false ->
1524		translate_bexpression_with_limit(Cond,100,CS),
1525		add_wd_error_span(ErrMsg,CS,span_predicate(Cond,LocalState,State),WF2),
1526		get_last_wait_flag(assertion_expression,WF2,WFC),
1527		when(nonvar(WFC),
1528		(ground_value(Value) -> true % we have a WD Error, any Value goes
1529		; b_compute_expression(Expr,LocalState,State,Value,WF2) % compute Value; avoid infinite enumeration of possible values; useful e.g. for prj1/prj2 assertion expressions
1530		))
1531	?	; b_compute_expression(Expr,LocalState,State,Value,WF),
1532		add_wd_error_if_false(PredRes,ErrMsg,Cond,span_predicate(Cond,LocalState,State),WF2)
1533		). %% NOT COVERED (34)
1534		b_compute_expression2(multiplication(Arg1,Arg2),integer,Info,LocalState,State,Value,WF) :-
1535		same_texpr(Arg1,Arg2), !, % is less useful when CLPFD is already turned on, calls square(Arg1,Value,WF)
1536		b_compute_expression(Arg1,LocalState,State,SV1,WF),
1537		unary_kernel_call(kernel_objects,square,SV1,Value,WF,multiplication(Arg1,Arg1),integer,Info).
1538		b_compute_expression2(image(Relation,Set),_EType,Info,LocalState,State,Value,WF) :-
1539		special_operator_for_image(Relation,Kind,Args),
1540		% we have closure1(Rel)[Set] or similar -> avoid computing full closure
1541		!,
1542		opt_push_wait_flag_call_stack_info(WF,b_operator_call(image,[Relation,SV],Info),WF2),
1543	?	b_compute_expression(Set,LocalState,State,SV,WF2),
1544		b_compute_expressions(Args,LocalState,State,EArgs,WF2),
1545	?	kernel_call(bsets_clp:image_for_special_operator(Kind,EArgs,SV,Value,WF2),[SV|EArgs],WF2,image(Relation,Set)).
1546		b_compute_expression2(external_function_call(FunName,Args),EType,Info,LocalState,State,Value,WF) :-
1547		!,
1548	?	b_compute_expressions(Args, LocalState,State, EvaluatedArgs, WF),
1549		push_wait_flag_call_stack_info(WF,external_call(FunName,EvaluatedArgs,Info),WF2),
1550	?	call_external_function(FunName,Args,EvaluatedArgs,Value,EType,Info,WF2).
1551		b_compute_expression2(Expression,EType,Info,LocalState,State,Res,WF) :-
1552		is_set_type(EType,Type),
1553		/* avoid evaluating certain expensive expressions:
1554		convert them into symbolic closures and expand only if really required */
1555		functor(Expression,UnOp,1),
1556		symbolic_closure_unary_operator(UnOp),
1557		/* TO DO: UNFOLD THIS OR WRAP in CONSTRUCTOR */
1558		arg(1,Expression,BType),
1559		!, %preferences:get_preference(convert_types_into_closures,true),!,
1560		% print_message(delayed_un_op(UnOp,BType)),
1561	?	b_compute_expression(BType,LocalState,State,ArgValue,WF),
1562		( do_not_keep_symbolic_unary(UnOp,ArgValue),
1563		unary_function(UnOp,Module,KernelFunction) ->
1564		/* special treatment for empty set or other situations: no need to keep symbolic */
1565	?	unary_kernel_call(Module,KernelFunction,ArgValue,Res,WF,Expression,EType,Info)
1566		;
1567		get_texpr_type(BType,ArgType),
1568		create_texpr(value(ArgValue),ArgType,[],TValue),
1569		ClosureSetExpression =.. [UnOp,TValue],
1570		construct_member_closure('_zzzz_unary',Type,Info,ClosureSetExpression,Value),
1571	?	((unop_to_be_marked_as_symbolic(UnOp,ArgValue) ; member(prob_annotation('SYMBOLIC'),Info)) ->
1572		mark_closure_as_symbolic(Value,SValue),
1573		equal_object_wf(Res,SValue,WF)
1574		; equal_object_wf(Res,Value,WF))
1575
1576		).
1577		b_compute_expression2(Expression,EType,Info,LocalState,State,Res,WF) :-
1578		is_set_type(EType,Type),
1579		/* avoid evaluating certain expensive expressions:
1580		convert them into symbolic closures and expand only if really required */
1581		functor(Expression,BinOp,2),
1582		arg(1,Expression,BType1),
1583		arg(2,Expression,BType2),
1584		kernel_mappings:symbolic_closure_binary_operator(BinOp),
1585		!,
1586		%preferences:get_preference(convert_types_into_closures,true),!,
1587	?	b_compute_expression(BType1,LocalState,State,ArgValue1,WF),
1588		(binary_arg1_determines_value(BinOp,ArgValue1,DetResult)
1589		-> /* print(det(BinOp,ArgValue1)),nl, */
1590		equal_object_wf(Res,DetResult,b_compute_expression2(BinOp),WF)
1591		; b_compute_expression(BType2,LocalState,State,ArgValue2,WF),
1592		% print_message(delayed_bin_op(BinOp,ArgValue1,ArgValue2)),
1593		(is_definitely_empty(BinOp,ArgValue1,ArgValue2)
1594		-> empty_set(Res)
1595		; if(do_not_keep_symbolic(BinOp,ArgValue1,ArgValue2,ERes,WF),
1596		% then:
1597		equal_object_wf(Res,ERes,b_compute_expression2(BinOp),WF),
1598		% else:
1599		(get_texpr_type(BType1,TypeArg1), create_texpr(value(ArgValue1),TypeArg1,[],TArg1),
1600		get_texpr_type(BType2,TypeArg2), create_texpr(value(ArgValue2),TypeArg2,[],TArg2),
1601		ClosureSetExpression =.. [BinOp,TArg1,TArg2],
1602		construct_member_closure('_zzzz_unary',Type,Info,ClosureSetExpression,Value),
1603		% print('Constructed Symbolic Closure : '), translate:print_bvalue(Value),nl,
1604	?	(binop_to_be_marked_as_symbolic(BinOp,ArgValue1,ArgValue2) ->
1605		mark_closure_as_symbolic(Value,SValue),
1606		equal_object_wf(Res,SValue,WF)
1607		; equal_object_wf(Res,Value,WF))
1608		)
1609		) % if
1610		)
1611		).
1612		b_compute_expression2(Expression,Type,Info,LocalState,State,Value,WF) :-
1613		functor(Expression,Op,1),
1614		unary_function(Op,Module,KernelFunction),
1615		arg(1,Expression,Arg1),!,
1616		%opt_push_wait_flag_call_stack_info(WF,b_operator_arg_evaluation(Op,1,[SV1],Arg1),WF1),
1617	?	b_compute_expression(Arg1,LocalState,State,SV1,WF),
1618	?	unary_kernel_call(Module,KernelFunction,SV1,Value,WF,Expression,Type,Info).
1619		b_compute_expression2(Expression,Type,Info,LocalState,State,Value,WF) :-
1620		functor(Expression,Op,2),
1621		binary_function(Op,Module,KernelFunction),
1622		arg(1,Expression,Arg1),
1623		arg(2,Expression,Arg2),!,
1624		%opt_push_wait_flag_call_stack_info(WF,b_operator_arg_evaluation(Op,1,[SV1,_],Arg1),WF1),
1625	?	b_compute_expression(Arg1,LocalState,State,SV1,WF),
1626		(binary_arg1_determines_value(Op,SV1,Result) % we could disable this if find_abort_values=true or if SV1 not guaranteed to be wd
1627		->
1628		equal_object_wf(Value,Result,b_compute_expression2(Op),WF)
1629	?	; b_compute_expression(Arg2,LocalState,State,SV2,WF),
1630	?	binary_kernel_call(Module,KernelFunction,SV1,SV2,Value,WF,Expression,Type,Info)
1631		).
1632		b_compute_expression2(operation_call_in_expr(Operation,Parameters),_T,Info,LocalState,State,Value,WF) :-
1633		!, def_get_texpr_id(Operation,op(OperationName)),
1634		% TODO: check that this is a query operation; probably done in type checker
1635		b_execute_operation_in_expression(OperationName,LocalState,State,Parameters,Value,Info,WF).
1636		b_compute_expression2(E,T,Info,_L,_S,_R,_WF) :-
1637		(T==pred -> add_internal_error('Uncovered expression; looks like a predicate in the wrong place: ',b(E,T,Info))
1638		; T==subst -> add_internal_error('Uncovered expression; looks like a substitution in the wrong place: ',b(E,T,Info))
1639		; requires_cleanup_pre(E) -> add_internal_error('Non-cleaned up ambiguous expression: ',b(E,T,Info))
1640		; add_internal_error('Uncovered expression: ',b(E,T,Info))
1641		),
1642		print_functor(E), print(' : '), print(T),nl,fail.
1643
1644		requires_cleanup_pre(mult_or_cart(_,_)).
1645		requires_cleanup_pre(minus_or_set_subtract(_,_)).
1646
1647		make_couplise([A],R) :- !,R=A.
1648		make_couplise([A,B],R) :- !,R=(A,B).
1649		make_couplise([A,B|Rest],Result) :- !,
1650		make_couplise([(A,B)|Rest],Result).
1651		make_couplise(A,_) :- add_internal_error('Illegal operation call result:',A),fail.
1652
1653		% ---
1654
1655
1656		% check if a symbolic_closure_unary_operator result should be marked with prob_annotation(SYMBOLIC)
1657		% because direct sub-args are marked SYMBOLIC
1658		unop_to_be_marked_as_symbolic(UnOp,Value) :- nonvar(Value),
1659	?	to_be_marked_as_symbolic_aux(UnOp,Value).
1660		to_be_marked_as_symbolic_aux(struct,rec(Fields)) :- !,
1661	?	member(field(_,SymbolicClosure),Fields),
1662	?	is_symbolic_closure(SymbolicClosure).
1663		%to_be_marked_as_symbolic_aux(pow_subset,SymbolicClosure) :- is_symbolic_closure(SymbolicClosure).
1664		%to_be_marked_as_symbolic_aux(pow1_subset,SymbolicClosure) :- is_symbolic_closure(SymbolicClosure).
1665	?	to_be_marked_as_symbolic_aux(_,SymbolicClosure) :- is_symbolic_closure(SymbolicClosure).
1666
1667		% check if a symbolic_closure_binary_operator result should be marked with prob_annotation(SYMBOLIC)
1668		% because direct sub-args are marked SYMBOLIC
1669		binop_to_be_marked_as_symbolic(interval,_,_) :- !, fail.
1670		%binop_to_be_marked_as_symbolic(overwrite,_,_) :- !, true. % TO DO: fix by detecting infinite <+ closures
1671	?	binop_to_be_marked_as_symbolic(set_subtraction,ArgVal1,_) :- !, is_symbolic_closure(ArgVal1).
1672		binop_to_be_marked_as_symbolic(intersection,ArgVal1,ArgVal2) :-
1673	?	(finite_reasonably_sized_set(ArgVal1) ; finite_reasonably_sized_set(ArgVal2)), !,
1674		fail. % intersection is finite and reasonably sized
1675	?	binop_to_be_marked_as_symbolic(_,ArgVal1,_) :- is_symbolic_closure(ArgVal1).
1676	?	binop_to_be_marked_as_symbolic(_,_,ArgVal2) :- is_symbolic_closure(ArgVal2).
1677		% ---
1678
1679		% check if we have a finite known set that can be reasonably represented
1680		% see small_known_set/1 is kernel_mappings
1681		finite_reasonably_sized_set(AVL) :- nonvar(AVL), AVL=avl_set(_). % already expanded; so it can be represented in memory
1682		finite_reasonably_sized_set(Closure) :- nonvar(Closure),
1683		custom_explicit_sets:is_interval_closure(Closure,From,To), integer(From), integer(To),
1684		1+To-From < 250000. % what value should we use here?
1685
1686		lazy_compute_expression(TRIGGER,AssignmentExpr,LocalState,State,IdValue,WF,Ai) :-
1687		get_enumeration_finished_wait_flag(WF,F),
1688		block_lazy_compute_expression(TRIGGER,F,AssignmentExpr,LocalState,State,IdValue,WF,Ai).
1689
1690		:- block block_lazy_compute_expression(-,-,?,?,?, ?,?,?).
1691		block_lazy_compute_expression(TRIGGER,_F,_AssignmentExpr,_LocalState,_State,_IdValue,_WF,_Ai) :-
1692		var(TRIGGER),!.
1693		block_lazy_compute_expression(pred_true,_,AssignmentExpr,LocalState,State,IdValue,WF,Ai) :-
1694		AssignmentExpr = b(Expr,Type,Infos),
1695		(Type \== pred -> b_compute_expression2(Expr,Type,Infos,LocalState,State,IdValue,WF)
1696		; IdValue == pred_true -> b_test_boolean_expression2(Expr,Infos,LocalState,State,WF,Ai,_)
1697		; IdValue == pred_false -> b_not_test_boolean_expression2(Expr,Infos,LocalState,State,WF,Ai,_)
1698		; b_check_boolean_expression(AssignmentExpr,LocalState,State,WF,PredVal,Ai,_) -> IdValue = PredVal
1699		; % reification of check_boolean_expression failed:
1700		b_try_check_failed(AssignmentExpr,LocalState,State,'$ENUMERATION',WF,IdValue,'$GENERATE_ON_DEMAND')
1701		).
1702		block_lazy_compute_expression(pred_false,_,_AssignmentExpr,_LocalState,_State,[],_WF,_Ai). % maybe generate any value ??
1703
1704		% ---
1705
1706		:- block add_wd_error_if_false(-,?,?,?,?).
1707		add_wd_error_if_false(pred_true,_,_,_,_).
1708		add_wd_error_if_false(pred_false,ErrMsg,Cond,Span,WF) :-
1709		translate_bexpression_with_limit(Cond,100,CS),
1710		%(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),
1711		add_wd_error_span(ErrMsg,CS,Span,WF).
1712
1713		% ---
1714
1715
1716		:- use_module(kernel_tools,[ground_value/1]).
1717		% compute function application:
1718		b_compute_expression_function(Function,FunArg,Type,Info,LocalState,State,Res,WF) :-
1719		preferences:preference(find_abort_values,false), % below we do not check, e.g., if set extension is really a function
1720		is_extension_function(Function,FInfo,ExFun), !,
1721		/* a set extension applied to an argument: in some cases we can can first evaluate the argument,
1722		and then avoid having to compute the set_extension for all non-matching args */
1723		opt_push_wait_flag_call_stack_info(WF,function_call(Function,ArgValue,Info),WF2), % only push call_stack in TRACE_INFO mode
1724		b_compute_expression(FunArg,LocalState,State,ArgValue,WF2),
1725		% TO DO : should we only do this if ArgValue is known ?? otherwise the standard treatment is better ??
1726		% Note: b_compiler has a special rule to not remove this optimisation
1727		Span = span_predicate(b(function(Function,FunArg),Type,Info),LocalState,State),
1728		((memberchk(contains_wd_condition,FInfo) ; % relevant for test 1302; but machine seems to contain real WD error
1729		preferences:preference(use_clpfd_solver,false) ;
1730		ground_value(ArgValue))
1731		-> b_apply_function_set_extension(ExFun,ArgValue,LocalState,State,Res,WF2,Span)
1732		; /* the standard treatment can infer information about the result,... in clpfd_mode */
1733		b_compute_expression(Function,LocalState,State,FValue,WF),
1734		get_texpr_type(Function,FunctionType),
1735		kernel_call_apply_to(FValue,ArgValue,Res,FunctionType,Span,WF2)).
1736		%b_compute_expression_function(b(comprehension_set(Parameters,Condition),_,SInfo),Arg,Type,Info,LocalState,State,Value,WF) :- !,
1737		% b_compute_comprehension_set_symbolic(Parameters,Condition,SInfo,LocalState,State,FValue,WF),
1738		% b_compute_expression(Arg,LocalState,State,ArgValue,WF),
1739		% Span = span_predicate(b(function(Function,Arg),Type,Info),LocalState,State),
1740		% get_texpr_type(Function,FunctionType),
1741		% kernel_call_apply_to(FValue,ArgValue,Value,FunctionType,Span,WF).
1742		b_compute_expression_function(Function,FunArg,_Type,Info,LocalState,State,Value,WF) :-
1743		special_operator_for_image(Function,Kind,Args),!, % detect e.g. iterate(rel,k)(x) or closure1
1744		opt_push_wait_flag_call_stack_info(WF,function_call(Function,ArgValue,Info),WF2),
1745		b_compute_expression(FunArg,LocalState,State,ArgValue,WF2),
1746		b_compute_expressions(Args,LocalState,State,EArgs,WF2),
1747		kernel_call(bsets_clp:apply_fun_for_special_operator(Kind,EArgs,ArgValue,Value,WF2,Info),
1748		[ArgValue|EArgs],WF2,function(Function,FunArg)).
1749		b_compute_expression_function(Function,Arg,Type,Info,LocalState,State,Value,WF) :-
1750		opt_push_wait_flag_call_stack_info(WF,function_call(Function,ArgValue,Info),WF2),
1751	?	b_compute_expression(Function,LocalState,State,FValue,WF2),
1752	?	b_compute_expression(Arg,LocalState,State,ArgValue,WF2),
1753		Span = span_predicate(b(function(Function,Arg),Type,Info),LocalState,State),
1754		get_texpr_type(Function,FunctionType),
1755		% TODO: do we still need the span predicate when we have the function_call call_stack infos?
1756	?	kernel_call_apply_to(FValue,ArgValue,Value,FunctionType,Span,WF2).
1757
1758
1759		:- use_module(bsyntaxtree,[get_set_type/2,is_set_type/2]).
1760		:- use_module(kernel_cardinality_attr,[finite_cardinality_as_int_with_type_wf/5]).
1761		b_compute_card(Arg1,Type,Info,OuterInfo,LocalState,State,Card,WF) :-
1762	?	b_compute_card2(Arg1,Type,Info,OuterInfo,LocalState,State,Card,WF),
1763		% maybe we should move this code below inside kernel_objects ??
1764		(ground(Card) -> true
1765		; get_set_type(Type,SetElType), % TO DO: only needed for cardinality_of_set_extension_list
1766	?	kernel_objects:max_cardinality(SetElType,MaxCard), % this could be precomputed statically
1767		(number(MaxCard) -> kernel_objects:in_nat_range(Card,int(0),int(MaxCard))
1768		; kernel_objects:greater_than_equal(Card,int(0)) % not sure this is required
1769		)
1770		).
1771		b_compute_card2(set_extension(Ex),_,_,_,LocalState,State,Card,WF) :- !,
1772		b_compute_expressions(Ex,LocalState,State,ExValue,WF),
1773		kernel_objects:cardinality_of_set_extension_list(ExValue,Card,WF).
1774		b_compute_card2(range(F),_,_,_,LocalState,State,Card,WF) :- !,
1775		b_compute_expression(F,LocalState,State,SV1,WF),
1776		kernel_objects:cardinality_of_range(SV1,Card,WF).
1777		b_compute_card2(comprehension_set(Parameters,Condition),Type,Info,OuterInfo,LocalState,State,Card,WF) :- !,
1778		get_set_type(Type,SetElType),
1779		% ensure that we keep the closure and don't expand it:
1780	?	b_compute_comprehension_set_symbolic(Parameters,Condition,Info,LocalState,State,SV1,WF),
1781	?	kernel_mappings:must_succ_kernel_call(
1782		kernel_cardinality_attr:finite_cardinality_as_int_with_type_wf(SV1,SetElType,OuterInfo,Card,WF),SV1,WF,card).
1783		% TO DO: treat comprehension set + things like card({x|x>1 & x<2**e & x mod 2 = 0}) = 0
1784		b_compute_card2(Arg1,Type,Info,OuterInfo,LocalState,State,Card,WF) :-
1785		get_set_type(Type,SetElType),
1786		b_compute_expression2(Arg1,Type,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
1790		b_compute_max(set_extension(Ex),_,Info,LocalState,State,Max,WF) :- !,
1791		b_compute_expressions(Ex,LocalState,State,ExValue,WF),
1792		kernel_objects:maximum_of_set_extension_list(ExValue,Max,Info,WF).
1793		b_compute_max(Arg1,Type,Info,LocalState,State,Max,WF) :-
1794		b_compute_expression2_symbolic(Arg1,Type,Info,LocalState,State,SV1,WF),
1795		kernel_mappings:must_succ_kernel_call(kernel_objects:maximum_of_set(SV1,Max,Info,WF),SV1,WF,max).
1796
1797		b_compute_min(set_extension(Ex),_,Info,LocalState,State,Min,WF) :- !,
1798		b_compute_expressions(Ex,LocalState,State,ExValue,WF),
1799		kernel_objects:minimum_of_set_extension_list(ExValue,Min,Info,WF).
1800		/* doesnot really buy a lot: */
1801		/*b_compute_min(union(Arg1,Arg2),_,Info,LocalState,State,Min,WF) :-
1802		Arg1 = b(set_extension(Ex),Type1,Info1),
1803		!,
1804		b_compute_min(set_extension(Ex),Type1,Info1,LocalState,State,Min1,WF),
1805		b_compute_expression(Arg2,LocalState,State,SV2,WF),
1806		b_compute_min2(SV2,Min1,Min,Info,WF).
1807		:- block b_compute_min2(-,?,?,?,?).
1808		b_compute_min2([],Min1,Res,_,_WF) :- !, Res=Min1.
1809		b_compute_min2(SV1,Min1,Res,Info,WF) :-
1810		kernel_mappings:must_succ_kernel_call(kernel_objects:minimum_of_set(SV1,Min2,Info,WF),SV1,WF,min),
1811		min(Min1,Min2,Res).
1812		min(int(A),int(B),int(Res)) :- kernel_objects:minimum(A,B,Res). */
1813		b_compute_min(Arg1,Type,Info,LocalState,State,Min,WF) :-
1814		b_compute_expression2_symbolic(Arg1,Type,Info,LocalState,State,SV1,WF),
1815		kernel_mappings:must_succ_kernel_call(kernel_objects:minimum_of_set(SV1,Min,Info,WF),SV1,WF,min).
1816
1817		generate_recursive_closure(TRecId,RecValue,Parameters,Condition,LocalState,State,Result,WF) :-
1818		get_texpr_id(TRecId,RecId),
1819		add_var_to_localstate(RecId,RecValue,LocalState,State1),
1820		debug_println(9,generating_recursive_closure(RecId,Parameters)),
1821		b_generate_rec_closure_aux(RecId,Parameters,Condition,State1,State,RClosure1,WF),
1822		mark_closure_as_recursive(RClosure1,RClosure2),
1823		mark_closure(RClosure2,[recursive(TRecId)],Result),
1824		( debug_mode(off) -> true
1825		; ground_value(Result) -> true
1826		; term_variables(Result,TV),
1827		add_message(b_interpreter,'non-ground closure generated: ',TV:Result,Condition)
1828		).
1829		% a variation of b_generate_closure
1830		b_generate_rec_closure_aux(RecId,Parameters,Condition,LocalState,State,Result,WF) :-
1831		split_names_and_types(Parameters,Names,Types),
1832		construct_closure(Names,Types,ClosurePred,Result),
1833		% now add RecId to parameters to prevent looking up recursive calls
1834		b_compiler:b_compile(Condition,[RecId|Names],LocalState,State,ClosurePred,WF).
1835
1836		% check if a freetype value has the expected case, if not
1837		% generate a WD-error
1838		check_freetype_case(Id,Case,VCase,Inner,Value,Info,WF) :-
1839		get_enumeration_finished_wait_flag(WF,F),
1840		check_freetype_case2(Id,Case,VCase,Inner,Value,Info,F,WF).
1841		:- block check_freetype_case2(?,?,-,?,?,?,-,?).
1842		check_freetype_case2(Id,Case,VCase,Inner,Value,Info,_F,WF) :-
1843		( nonvar(VCase) ->
1844		( Case=VCase -> equal_object_wf(Inner,Value,check_freetype_case2,WF)
1845		;
1846		ajoin(['cannot apply destructor for data type ',Id,
1847		', expected constructor ',Case,', but got: '],Msg),
1848		add_wd_error_set_result(Msg,VCase,Inner,Value,Info,WF))
1849		; % the computation has finished without value,
1850		true). % just drop the check
1851
1852		% check if we have a set_extension argument representing an explicit function
1853		% {a |-> f1, b |-> f2, ...} or [f1,f2]
1854		is_extension_function(b(A,_,Info),Info,C) :- is_extension_function_aux(A,C).
1855		is_extension_function_aux(set_extension(Ex),CaseList) :- is_set_extension_function(Ex,CaseList).
1856		is_extension_function_aux(sequence_extension(Ex),CaseList) :- is_sequence_extension_function(Ex,1,CaseList).
1857		is_set_extension_function([],[]).
1858		is_set_extension_function([b(Couple,TC,_)|T],[case(A,B)|ST]) :- is_couple(Couple,TC,A,B),
1859		is_set_extension_function(T,ST).
1860		is_sequence_extension_function([],_,[]).
1861		is_sequence_extension_function([B|T],Nr,[case(b(value(int(Nr)),integer,[]),B)|ST]) :- N1 is Nr+1,
1862		is_sequence_extension_function(T,N1,ST).
1863
1864		is_couple(couple(A,B),_,A,B).
1865		is_couple(value((VA,VB)),couple(TA,TB), b(value(VA),TA,[]), b(value(VB),TB,[])).
1866
1867		:- use_module(kernel_equality,[equality_objects_wf/4]).
1868		b_apply_function_set_extension([],FunArgVal,_LocalState,_State,_Res,WF,Span) :-
1869		add_wd_error_span('Function applied outside of domain (#8): ','@fun'(FunArgVal,[]),Span,WF).
1870		b_apply_function_set_extension([case(A,B)|T],FunArgVal,LocalState,State,Res,WF,Span) :-
1871		b_compute_expression(A,LocalState,State,AVal,WF),
1872		equality_objects_wf(AVal,FunArgVal,EqRes,WF),
1873		% TO DO: if Res is known, we can call equality_objects(BVal,Res,ResEqRes)
1874		b_apply_function_set_extension_aux(EqRes,B,T,FunArgVal,LocalState,State,Res,WF,Span).
1875
1876		:- block b_apply_function_set_extension_aux(-,?,?,?, ?,?,?,?,?).
1877		b_apply_function_set_extension_aux(pred_true,B,_T,_FunArgVal,LocalState,State,Res,WF,_Span) :-
1878		b_compute_expression(B,LocalState,State,BVal,WF), %print(value(BVal)),nl,
1879		equal_object_wf(BVal,Res,b_apply_function_set_extension_aux,WF).
1880		b_apply_function_set_extension_aux(pred_false,_B,T,FunArgVal,LocalState,State,Res,WF,Span) :-
1881		b_apply_function_set_extension(T,FunArgVal,LocalState,State,Res,WF,Span).
1882
1883
1884		% --------------------- SIGMA & PI ------------------------
1885		:- use_module(bsyntaxtree,[is_membership_or_equality/3,same_id/3]).
1886		/* first clause: try to do a specific treatment for formulas of the form SIGMA(ID).(ID:SET|EXPR) */
1887		/* Advantage: will not delay as long before computing comprehension_set SET ; see test 1312 */
1888		b_general_sum_or_mul([TID],Condition,Expression,Type,_Info,LocalState,State,SumResult,WF,SUMorMUL) :-
1889		is_membership_or_equality(Condition,MID,SET),
1890		same_id(TID,MID,_),!,
1891		b_compute_expression(SET,LocalState,State,SETResult,WF),
1892		b_general_sum_or_mul_over_set([TID],SETResult,Expression,Type,LocalState,State,SumResult,WF,SUMorMUL).
1893		b_general_sum_or_mul(Ids,Condition,Expression,Type,Info,LocalState,State,SumMulResult,WF,SUMorMUL) :-
1894		b_compute_comprehension_set(Ids,Condition,Info,LocalState,State,SETResult,WF),
1895		(var(SETResult) -> perfmessagecall(sigma_pi_not_expanded_or_reified(SUMorMUL),
1896		translate:print_bexpr(Condition),Condition) ; true),
1897		b_general_sum_or_mul_over_set(Ids,SETResult,Expression,Type,LocalState,State,SumMulResult,WF,SUMorMUL).
1898
1899
1900		:- block b_general_sum_or_mul_over_set(?,-, ?,?,?,?, ?,?,?).
1901		b_general_sum_or_mul_over_set([TID],SETResult,Expression,Type,_LS,_S,SumResult,WF,SUMorMUL) :-
1902		Type=integer, % TO DO: also for real
1903		get_texpr_id(Expression,ID), % check if we just sum the elements of the list SIGMA(x).(x:S|x)
1904		get_texpr_id(TID,ID),
1905	?	sum_or_mul_of_explicit_set(SETResult,SUMorMUL,R),!,
1906		equal_object_wf(SumResult,R,b_general_sum_or_mul_over_set,WF).
1907		b_general_sum_or_mul_over_set(IDs,SETResult,Expression,Type,LocalState,State,SumResult,WF,SUMorMUL) :-
1908		expand_custom_set_to_list_wf(SETResult,ESETResult,_Done,b_general_sum_or_mul_over_set,WF),
1909	?	b_sum_or_mul_over_list(ESETResult,IDs,Expression,Type,LocalState,State,SumResult,WF,SUMorMUL).
1910
1911		b_sum_or_mul_over_list(L,IDs,Expr,Type,LS,State,Result,WF,SUMorMUL) :-
1912		get_acc_base(SUMorMUL,Type,Acc),
1913		(Type = integer -> get_wait_flag0(WF,WF0) ; true), % for real: delay until values known
1914	?	b_sum_or_mul_over_list_acc(L,IDs,Expr,Type,LS,State,Acc,Result,WF,SUMorMUL,WF0).
1915
1916		:- block b_sum_or_mul_over_list_acc(-, ?, ?,?,?,?,?, ?,?,?,?).
1917		% better if list is fully known: no constraint propagation performed during computation !
1918		% for example: SIGMA(x).(x:{-1} \/ 1..30000|x+1) goes down from 2050 ms to 1210 ms
1919		b_sum_or_mul_over_list_acc([],_,_,Type,_,_,Acc,Result,_WF,_SUMorMUL,_) :-
1920	?	get_acc_result(Type,Acc,Result).
1921		b_sum_or_mul_over_list_acc([H|T],IDs,Expr,Type,LocalState,State,Acc,Result,WF,SUMorMUL,WF0) :-
1922		add_typed_vars_to_localstate(IDs,H,LocalState,NewLocalState),
1923		b_compute_expression(Expr,NewLocalState,State,HExprVal,WF),
1924		b_sum_or_mul_over_list_acc2(HExprVal,T,IDs,Expr,Type,LocalState,State,Acc,Result,WF,SUMorMUL,WF0).
1925
1926		:- block b_sum_or_mul_over_list_acc2(?,-, ?, ?,?,?,?,?, ?,?,?,?),
1927		b_sum_or_mul_over_list_acc2(?,?, ?, ?,?,?,?,-, ?,?,?,-),
1928		b_sum_or_mul_over_list_acc2(-,?, ?, ?,?,?,?,?, ?,?,?,-). % wait until T nonvar and either Acc & HExprVal known or WF0 set
1929		% purpose: try and remain in non-CLPFD mode as long as possible to avoid overflows,... (see eg. test 1642, 1708)
1930		b_sum_or_mul_over_list_acc2(HExprVal,T,IDs,Expr,Type,LocalState,State,Acc, Result,WF,SUMorMUL,WF0) :-
1931		(nonvar(T),nonvar(Acc),ground(HExprVal)
1932		-> % we can continue computing the system without constraint propagation; is faster
1933		get_value(Type,HExprVal,HVal),
1934		compose_acc(SUMorMUL,Acc,HVal,NewAcc),
1935		b_sum_or_mul_over_list_acc(T,IDs,Expr,Type,LocalState,State,NewAcc,Result,WF,SUMorMUL,WF0)
1936		; T==[], number(Acc), get_acc_base(SUMorMUL,Type,Acc) ->
1937		/* we have just a single element left and no operator has to be applied -> no need for clpfd treatment */
1938		equal_object_wf(HExprVal,Result,b_sum_or_mul_over_list_acc)
1939		; Type=real -> % no CLP(FD) treatment possible yet
1940		when(ground(HExprVal),
1941		b_sum_or_mul_over_list_acc2(HExprVal,T,IDs,Expr,Type,LocalState,State,Acc, Result,WF,SUMorMUL,WF0))
1942		; init_clp_acc(SUMorMUL,HExprVal,int(Acc),CLPAccumulator),
1943		b_sum_or_mul_over_list_clp(T,IDs,Expr,LocalState,State,CLPAccumulator,Result,WF,SUMorMUL)
1944		).
1945
1946		% add set comprehension solution ValueForTypedIDs as individual values for every TypedIDs to LocalState
1947		add_typed_vars_to_localstate(TypedIDs,ValueForTypedIDs,LocalState,NewLocalState) :-
1948		(flatten_pairs(TypedIDs,ValueForTypedIDs,ValAsList),
1949		add_typed_vars_to_localstate_aux(TypedIDs,ValAsList,LocalState,R)
1950		-> NewLocalState = R
1951		; add_internal_error('Call failed: ',add_typed_vars_to_localstate(TypedIDs,ValueForTypedIDs,LocalState,NewLocalState)),
1952		fail
1953		).
1954		% set comprehension results for {a,b,c|P} are nested like this ((a,b),c)
1955		% first argument only used for length (to know how deep the pairs are nested)
1956		flatten_pairs(L,Pairs,FlatList) :- flatten_pairs(L,Pairs,FlatList,[]).
1957		flatten_pairs([_],A) --> !, [A].
1958		flatten_pairs([_|T],(A,B)) --> flatten_pairs(T,A) ,[B].
1959		add_typed_vars_to_localstate_aux([],_,LS,LS).
1960		add_typed_vars_to_localstate_aux([TID],[H],LocalState,NewLocalState) :- !,
1961		get_texpr_id(TID,ID), get_texpr_type(TID,TYPE),
1962		add_typed_var_to_localstate(ID,H,TYPE,LocalState,NewLocalState).
1963		add_typed_vars_to_localstate_aux([TID1|Ids],[H1|Hs],LocalState,NewLocalState) :- !,
1964		get_texpr_id(TID1,ID1), get_texpr_type(TID1,TYPE),
1965		add_typed_var_to_localstate(ID1,H1,TYPE,LocalState,LS1),
1966		add_typed_vars_to_localstate_aux(Ids,Hs,LS1,NewLocalState).
1967
1968
1969		:- block b_sum_or_mul_over_list_clp(-, ?, ?,?,?, ?, ?,?,?).
1970		b_sum_or_mul_over_list_clp([],_, _,_,_, Acc, Result,_WF,SUMorMUL) :-
1971		finalise_clp(SUMorMUL,Acc,Result).
1972		b_sum_or_mul_over_list_clp([H|T],IDs,Expr,LocalState,State,Acc, Result,WF,SUMorMUL) :-
1973		add_typed_vars_to_localstate(IDs,H,LocalState,NewLocalState),
1974		b_compute_expression(Expr,NewLocalState,State,HExprVal,WF),
1975		compose_clp(SUMorMUL,HExprVal,Acc,NewAcc),
1976		b_sum_or_mul_over_list_clp(T,IDs,Expr,LocalState,State,NewAcc,Result,WF,SUMorMUL).
1977
1978		:- use_module(kernel_reals,[is_real/2]).
1979		get_acc_base(sum,integer,R) :- !, R=0.
1980		get_acc_base(sum,real,0.0).
1981		get_acc_base(mul,integer,R) :- !, R=1.
1982		get_acc_base(mul,real,1.0).
1983		get_acc_result(integer,Nr,int(Nr)).
1984		get_acc_result(real,Nr,Real) :- is_real(Real,Nr).
1985		get_value(integer,int(Val),Val) :- !.
1986		get_value(real,Real,Nr) :- is_real(Real,Nr).
1987
1988		compose_acc(sum,A,B,C) :- C is A+B.
1989		compose_acc(mul,A,B,C) :- C is A*B.
1990		init_clp_acc(sum,int(A),int(B),Res) :- (B==0 -> Res=[A] ; Res=[A,B]). % A always not ground
1991		init_clp_acc(mul,A,B,C) :- times(A,B,C).
1992		compose_clp(sum,int(A),Acc,NewAcc) :- NewAcc = [A|Acc].
1993		compose_clp(mul,A,B,C) :- times(A,B,C).
1994		:- use_module(clpfd_interface,[clpfd_sum/2]).
1995		finalise_clp(sum,Acc,int(Result)) :-
1996		clpfd_sum(Acc,Result). % using clpfd_sum can be much more efficient: no intermediate variables set up
1997		finalise_clp(mul,int(Acc),int(Acc)).
1998
1999		/* for if-then-else in Z: compute Then or Else,
2000		depending on the outcome of the predicate */
2001		:- block b_compute_if_then_else(-,?,?,?,?,?,?).
2002		b_compute_if_then_else(pred_true,Then,_Else,LocalState,State,Value,WF) :-
2003		opt_push_wait_flag_call_stack_info(WF,b_expr_call(if_then_body,Then),WF2),
2004	?	b_compute_expression(Then,LocalState,State,Value,WF2).
2005		b_compute_if_then_else(pred_false,_Then,Else,LocalState,State,Value,WF) :-
2006		opt_push_wait_flag_call_stack_info(WF,b_expr_call(if_else_body,Else),WF2),
2007	?	b_compute_expression(Else,LocalState,State,Value,WF2).
2008
2009		:- use_module(clpfd_interface,[clpfd_if_then_else/4]).
2010		% a more sophisticated treatment, can also work backwards forcing PredRes
2011		% examples:
2012		% x = IF a<10 THEN 0 ELSE 5 END & x:6..10 & a:1..23
2013		% see must_fail_clpfd_det 132 and 133
2014		% problematic if Else contains recursion; but then we should have WD condition
2015		b_clpfd_if_then_else(PredRes,Type,Then,Else,LocalState,State,Value,WF) :-
2016		get_wait_flag0(WF,WF0),
2017		b_clpfd_if_then_else_block(PredRes,WF0,Type,Then,Else,LocalState,State,Value,WF).
2018		:- block b_clpfd_if_then_else_block(-,-,?,?,?,?,?,?,?).
2019		b_clpfd_if_then_else_block(PredRes,_,Type,Then,Else,LocalState,State,Value,WF) :- var(PredRes),!,
2020		get_full_fd_value(Type,Value,FDValue),
2021		b_compute_expression(Then,LocalState,State,ThenValue,WF),
2022		get_full_fd_value(Type,ThenValue,FDThenValue),
2023		b_compute_expression(Else,LocalState,State,ElseValue,WF),
2024		get_full_fd_value(Type,ElseValue,FDElseValue),
2025		% TO DO: catch CLPFD overflow and use equality_objects
2026		clpfd_if_then_else(PredRes,FDThenValue,FDElseValue,FDValue).
2027		b_clpfd_if_then_else_block(pred_true,_,_Type,Then,_Else,LocalState,State,Value,WF) :-
2028		b_compute_expression(Then,LocalState,State,Value,WF).
2029		b_clpfd_if_then_else_block(pred_false,_,_Type,_Then,Else,LocalState,State,Value,WF) :-
2030		b_compute_expression(Else,LocalState,State,Value,WF).
2031
2032		:- use_module(b_global_sets,[get_global_type_value/3]).
2033		% try and get full_fd_value; true if full value can be translated to CLP(FD) value
2034		get_full_fd_value(global(T),FY,X) :- get_global_type_value(FY,T,X).
2035		get_full_fd_value(integer,int(X),X).
2036		get_full_fd_value(boolean,B,FD) :- kernel_equality:prop_eq_01(B,FD).
2037		% record with single field ?
2038
2039		can_get_full_fd_value(global(_)).
2040		can_get_full_fd_value(integer).
2041		can_get_full_fd_value(boolean).
2042
2043		% a slightly improved version over set_up_localstate (not sure it is really much faster):
2044		add_lazy_let_id_to_local_state(b(identifier(ID),_,_),Trigger,IdValue,LocalState,NewState) :-
2045		% should we delete any old occurence of ID in LocalState?
2046		NewState = [bind(ID,(Trigger,IdValue))|LocalState].
2047
2048		add_lazy_let_id_and_expression(Id,IdExpr,LocalState,InState,NewLocalState,WF) :-
2049		empty_avl(Ai),
2050		add_lazy_let_id_and_expression(Id,IdExpr,LocalState,InState,NewLocalState,WF,Ai).
2051		add_lazy_let_id_and_expression(Id,IdExpr,LocalState,InState,NewLocalState,WF,Ai) :-
2052		add_lazy_let_id_to_local_state(Id,Trigger,IdValue,LocalState,NewLocalState),
2053		lazy_compute_expression(Trigger,IdExpr,LocalState,InState,IdValue,WF,Ai).
2054
2055		/* for let-statements in Z and now in B: expand localstate by new variables and assign
2056		values to them ;
2057		now Expressions are evaluated in state *with* the new identifiers !
2058		*/
2059		%set_up_localstate_for_let_no_reuse(Ids,Exprs,LocalState,State,LetState,WF) :-
2060		% set_up_localstate(Ids,Vars,LocalState,LetState),
2061		% compute_let_expressions(Exprs,Vars,LocalState,State,WF).
2062		set_up_localstate_for_let(Ids,Vars,Exprs,LocalState,State,LetState,WF) :-
2063		set_up_localstate(Ids,Vars,LocalState,LetState),
2064		%external_functions:observe_variables(Ids,Vars),
2065	?	compute_let_expressions(Exprs,Vars,LetState,State,WF).
2066		compute_let_expressions([],[],_,_,_).
2067		compute_let_expressions([Expr|RestExprs],[Var|RestVars],LocalState,State,WF) :-
2068	?	b_compute_expression(Expr,LocalState,State,Value,WF),
2069		equal_object_optimized(Var,Value,compute_let_expressions),
2070		compute_let_expressions(RestExprs,RestVars,LocalState,State,WF).
2071
2072		set_up_localstate_for_global_let(Ids,Exprs,LocalState,State,LetState,WF) :-
2073		set_up_localstate(Ids,Vars,State,LetState),
2074		compute_let_expressions(Exprs,Vars,LocalState,LetState,WF).
2075
2076
2077		l_compute_field([],_LS,_S,[],_WF).
2078		l_compute_field([Field|T],LS,S,[FVal|CT],WF) :-
2079	?	b_compute_field(Field,LS,S,FVal,WF),
2080	?	l_compute_field(T,LS,S,CT,WF).
2081
2082		b_compute_field(field(Name,TypeOrVal),LocalState,State,field(Name,TypeOrFieldValue),WF) :-
2083	?	b_compute_expression(TypeOrVal,LocalState,State,TypeOrFieldValue,WF).
2084
2085
2086
2087		:- use_module(b_compiler).
2088
2089		/* :- type bsets_closure +--> closure(list(type(variable_id)),
2090		list(type(basic_type_descriptor)),type(boolean_expression)). */
2091
2092		:- assert_pre(b_interpreter:b_compute_comprehension_set(Parameters,Cond,_Info,LS,State,_R,_WF),
2093		(ground_check(Parameters),
2094		bsyntaxtree:check_if_typed_predicate(Cond),type_check(LS,store),type_check(State,store)) ).
2095
2096		:- assert_post(b_interpreter:b_compute_comprehension_set(_P,_C,_Info,_LS,_State,Val,_WF),
2097		(b_interpreter:value_type(Val))). %, nonvar(Val)
2098
2099
2100
2101		b_compute_comprehension_set_symbolic(Parameters,Condition,Info,LocalState,State,Result,WF) :-
2102		% a version which never expands the generated closure
2103	?	b_generate_closure_if_necessary(Parameters,Condition,LocalState,State,CResult,WF),
2104	?	(member(prob_annotation('SYMBOLIC'),Info)
2105		-> mark_closure_as_symbolic(CResult,CRS),Result=CRS
2106		; Result=CResult). % TODO: check if we need definitely_expand_this_explicit_set
2107		% we could catch Parameters = [TID], Condition = b(member(b(identifier(ID),_TYPE,_),SET)
2108		b_compute_comprehension_set(Parameters,Condition,Info,LocalState,State,Result,WF) :-
2109	?	b_generate_closure_if_necessary(Parameters,Condition,LocalState,State,CResult,WF),
2110		b_compute_comprehension_set_aux(CResult,Info,Result,WF).
2111
2112		:- use_module(clpfd_interface,[catch_clpfd_overflow_call2/2]).
2113		b_compute_comprehension_set_aux(CResult,_,Result,_WF) :-
2114		(var(CResult) ; \+ functor(CResult,closure,3) ),!,
2115		Result=CResult.
2116		b_compute_comprehension_set_aux(CResult,Info,Result,_WF) :-
2117	?	member(prob_annotation('SYMBOLIC'),Info),!,
2118		mark_closure_as_symbolic(CResult,CRS),Result=CRS.
2119		b_compute_comprehension_set_aux(CResult,Info,Result,WF) :-
2120		(preferences:get_preference(convert_comprehension_sets_into_closures,true)
2121		-> \+ definitely_expand_this_explicit_set(CResult)
2122		; dont_expand_symbolic_explicit_set(CResult), % Note: also detects FORCE annotation
2123		perfmessage_wf(symbolic,'Keeping comprehension-set symbolic (use FORCE to override this or increase SYMBOLIC_LIMIT)','',Info,WF)
2124		),!,
2125		Result=CResult.
2126		b_compute_comprehension_set_aux(CResult,Info,Result,WF) :-
2127		b_expand_compute_comprehension_set(CResult,Info,Result,WF).
2128
2129		b_expand_compute_comprehension_set(CResult,Info,Result,WF) :-
2130		% using just get_wait_flag1(b_compute_comprehension_set,WF,WF0), makes many benchmarks faster ; but e.g., test 268 fails; maybe we sholud pre-compute bexpr_variables ? and pass this to expand_only_custom_closure_global
2131		(preferences:preference(use_smt_mode,false)
2132		-> get_wait_flag(1000,b_compute_comprehension_set,WF,WF0) % ideally we should say WF0 = _ ; but for some benchmarks Rule_DB_SIGAREA_0024_ori.mch this is important to avoid expanding closures before other stuff fails
2133		% only in SMT mode can there be any benefit in expanding a non-ground closure (when it is a lambda closure)
2134		% => hence delay expansion longer, possibly detecting enumeration warnings while expanding
2135		% TO DO: for lambda closures with known domain: expand earlier !
2136		; get_wait_flag(2,b_compute_comprehension_set,WF,WF0)),
2137		kernel_objects:mark_as_to_be_computed(Result), % avoid that we instantiate this set (e.g., in check_element_of_wf: we will get a full description of the set later; see test 1353
2138		(var(WF0),var(Result) -> ground_value_check(CResult,CGr) ; true),
2139		block_compute_comprehension_set_aux(CResult,Info,Result,WF,WF0,CGr).
2140
2141		:- block block_compute_comprehension_set_aux(?,?,-,?,-,-).
2142		block_compute_comprehension_set_aux(CResult,Info,Result,WF,_WF0,_CGr) :-
2143		(
2144		nonvar(Result)
2145	?	-> equal_object_wf(CResult,Result,WF) % this may expand CResult or do other tests;
2146		% like emptyness test or symbolic equality;
2147		% if Result=[_|_] then the closure needs to be expanded anyhow, so need to try and keep symbolic
2148		;
2149	?	catch_clpfd_overflow_call2(
2150		on_enumeration_warning_with_continue(expand_only_custom_closure_global(CResult,Expansion,check_no_inf,WF),
2151		% check_no_inf: we know it is not definitely infinite; and we do not want warnings for virtual time-outs
2152		% an enumeration warning occured in the expansion scope: keep closure symbolic after all
2153		% NOTE: for this detection to work it is better to delay until the body is ground (CGr)
2154		% and not use a priority too low for WF0, otherwise Expansion will be var and enum warning may occur later
2155		b_compute_comprehension_set_sym_msg(CResult,Info,Result,WF) % Backup Call in case of enum warning
2156		,
2157		equal_object_wf(Result,Expansion,WF) % TrueContinuation
2158		% instantiating Result can trigger other code which fails and confuses on_enumeration_warning
2159		),
2160		b_compute_comprehension_set_sym(CResult,Result,WF)
2161		) % catch_clpfd_overflow_call2
2162		).
2163
2164		b_compute_comprehension_set_sym_msg(CResult,Info,Result,WF) :- CResult = closure(P,_T,B),
2165		silent_mode(off),
2166		% TO DO: should we check that this closure has not been constructed by ProB, e.g., for UNION ??
2167		% e.g., P = ['__RANGE_LAMBDA__'] what about '_zzzz_unary', '_zzzz_binary', '_prj_arg1__', ...
2168		% also: what if the enumeration warning has a pending_abort_error
2169		!,
2170		Msg = 'Keeping comprehension-set symbolic (you may want to use the /*@symbolic*/ pragma to prevent this message, unless it was due to a WD-Error), identifiers: ',
2171		(contains_info_pos(Info) -> Span=Info ; Span=B),
2172		add_message(b_compute_comprehension_set,Msg,P,Span),
2173		b_compute_comprehension_set_sym(CResult,Result,WF).
2174		b_compute_comprehension_set_sym_msg(CResult,_,Result,WF) :-
2175		b_compute_comprehension_set_sym(CResult,Result,WF).
2176
2177
2178		b_compute_comprehension_set_sym(CResult,Result,WF) :-
2179		mark_closure_as_symbolic(CResult,CRS), % prevent doing the same mistake again
2180		equal_object_wf(Result,CRS,b_compute_comprehension_set_sym,WF).
2181
2182
2183		:- use_module(closures,[construct_closure_if_necessary/4]).
2184		b_generate_forall_closure(Parameters,Condition,LocalState,State,Result,WF) :-
2185		split_names_and_types(Parameters,Names,Types),
2186		construct_closure(Names,Types,ClosurePred1,Result),
2187		(LocalState==[],State==[]
2188		-> ClosurePred = Condition % no lookups can be performed anyway; no need to compile
2189		; b_compiler:b_compile(Condition,Names,LocalState,State,ClosurePred,WF) ),
2190		add_texpr_infos(ClosurePred,[quantifier_kind(forall)],ClosurePred1). % info for call_stack
2191
2192
2193
2194		b_generate_closure_if_necessary(Parameters,Condition,LocalState,State,Result,WF) :-
2195		split_names_and_types(Parameters,Names,Types),
2196	?	b_compiler:b_compile(Condition,Names,LocalState,State,ClosurePred,WF),
2197		%print('COMPILED: '),translate:print_bexpr(ClosurePred),nl,
2198		construct_closure_if_necessary(Names,Types,ClosurePred,Result).
2199
2200
2201		:- public convert_list_of_expressions_into_sequence/2.
2202		convert_list_of_expressions_into_sequence(List,SeqValue) :-
2203		convert_list_of_expressions_into_sequence(List,1,Seq),
2204	?	equal_object_optimized(Seq,SeqValue,convert_list_of_expressions_into_sequence).
2205
2206		convert_list_of_expressions_into_sequence([],_,[]).
2207		convert_list_of_expressions_into_sequence([H|T],Cur,[(int(Cur),H)|ConvT]) :-
2208		C1 is Cur+1,
2209		convert_list_of_expressions_into_sequence(T,C1,ConvT).
2210
2211		convert_list_of_expressions_into_set_wf(ListOfElements,Set,Type,WF) :-
2212		list_of_expressions_is_ground(ListOfElements,Ground,OrderedListOfElements),
2213	?	convert_list_of_expressions_into_set1(Ground,OrderedListOfElements,Set,Type,WF).
2214		convert_list_of_expressions_into_set1(true,ListOfElements,Set,_Type,WF) :- %var(Set),
2215	?	\+ (ListOfElements = [H|_], is_symbolic_closure(H)), % list contains symbolic closures, do not try to expand to avl
2216		% see should_be_converted_to_avl_from_lists ?
2217		!, construct_avl_from_lists_wf(ListOfElements,AVLSet,WF),
2218	?	equal_object_wf(AVLSet,Set,convert_list_of_expressions_into_set1,WF).
2219		convert_list_of_expressions_into_set1(_,Seq,Set,Type,WF) :-
2220	?	kernel_objects:max_cardinality(Type,TypeMaxCard),
2221	?	convert_list_of_expressions_into_set2(Seq,1,[],Set,TypeMaxCard,WF).
2222
2223		% TO DO: sort elements : ground elements first
2224		convert_list_of_expressions_into_set2([],_,Set,Res,_,WF) :-
2225	?	equal_object_wf(Set,Res,convert_list_of_expressions_into_set2,WF).
2226		convert_list_of_expressions_into_set2([H|T],MaxSze,SetSoFar,OutSet,TypeMaxCard,WF) :-
2227		%kernel_objects:basic_type_set(Type,IntSet,MaxSze),
2228		check_set_lists_bounded(IntSet,TypeMaxCard,MaxSze),
2229		% TO DO: optimize; avoid traversing or typing elements over and over again
2230		% maybe add a max. sze argument to add_element
2231		add_element_wf(H,SetSoFar,IntSet,WF), % print(add_el(H,SetSoFar,IntSet)),nl,
2232		% TO DO: check if H in OutSet and keep track of which elements have already been covered in OutSet
2233		%check_element_of_wf(H,OutSet,WF), makes tests 114, 115, 118-120, 1063 fail ! % we could also call lazy_try_check_element_of if this turns out to be too expensive
2234		kernel_objects:lazy_try_check_element_of(H,OutSet,WF),
2235		M1 is MaxSze+1,
2236	?	convert_list_of_expressions_into_set2(T,M1,IntSet,OutSet,TypeMaxCard,WF).
2237
2238
2239		:- use_module(inf_arith).
2240
2241		% check that a set does not exceed a certain bound (to prevent infinite
2242		% or overeager enumeration of sets); Warning: will not check custom_explicit_set sizes
2243		check_set_lists_bounded(Set,TypeMaxCard,Bound) :-
2244		inf_arith:infmin(TypeMaxCard,Bound,Card),
2245		(is_inf_or_overflow_card(Card) -> true
2246		; Card<1 -> empty_set(Set)
2247		; check_set_bounded_aux(Set,Card)).
2248
2249		:- block check_set_bounded_aux(-,?).
2250		check_set_bounded_aux(CustomSet,_) :- is_custom_explicit_set(CustomSet,check_set_bounded_aux),!.
2251		check_set_bounded_aux([],_).
2252		check_set_bounded_aux([_|T],Card) :-
2253		C1 is Card-1,
2254		(C1=0 -> empty_set(T) ; check_set_bounded_aux(T,C1)).
2255
2256
2257
2258		% check if the list can be converted into AVL form; if not: re-order list so that ground elements are present first
2259		list_of_expressions_is_ground([],true,[]).
2260		list_of_expressions_is_ground([E|T],Ground,ResList) :-
2261		(should_be_converted_to_avl(E) -> ResList=[E|RT], list_of_expressions_is_ground(T,Ground,RT)
2262		; Ground=false,
2263		bring_ground_elements_forward(T,[E],ResList)
2264		).
2265
2266		bring_ground_elements_forward([],Acc,Acc).
2267		bring_ground_elements_forward([H|T],Acc,Res) :-
2268		(should_be_converted_to_avl(H) -> Res=[H|RT], bring_ground_elements_forward(T,Acc,RT)
2269		; bring_ground_elements_forward(T,[H|Acc],Res)).
2270
2271		:- use_module(kernel_card_arithmetic,[is_inf_or_overflow_card/1, safe_mul/3]).
2272		% compute cardinality of a list of parameters, such as for forall
2273		parameter_list_cardinality([],1).
2274		parameter_list_cardinality([b(identifier(_),BasicType,_)|T],Res) :-
2275	?	parameter_list_cardinality(T,TCard),
2276		(is_inf_or_overflow_card(TCard) -> Res=TCard
2277	?	; kernel_objects:max_cardinality(BasicType,Card),
2278		safe_mul(Card,TCard,Res)
2279		).
2280		% see also basic_type_list_cardinality, now moved to custom_explicit_sets
2281
2282		b_for_all(Parameters,Infos,LHS,RHS,LocalState,State,WF) :-
2283		get_wait_flag1(for_all(Parameters),WF,LWF), % hack: give total_function,... priority to set up domain/range
2284	?	b_for_all_aux(LWF,Parameters,Infos,LHS,RHS,LocalState,State,WF).
2285
2286		:- block b_for_all_aux(-,?,?,?,?,?,?,?).
2287		b_for_all_aux(_,Parameters,Infos,LHS,RHS,LocalState,State,WF) :-
2288		split_names_and_types(Parameters,Names,Types),
2289	?	b_compile(LHS,Names,LocalState,State,CLHS,WF),
2290	?	b_compile(RHS,Names,LocalState,State,CRHS,WF),
2291	?	b_for_all_aux2(Parameters,Names,Types,Infos,CLHS,CRHS,WF).
2292
2293		:- use_module(kernel_tools,[ground_bexpr/1, ground_bexpr_check/2]).
2294		b_for_all_aux2(_,_,_,_,LHS,RHS,_) :-
2295		(is_falsity(LHS) ; is_truth(RHS)),
2296		!. % quantifier always true
2297		b_for_all_aux2(Parameters,CParameters,CParameterTypes,Infos,LHS,RHS,WF) :-
2298		ground_bexpr(LHS),
2299	?	\+ obvious_enumeration(LHS,CParameters), % if we have an obvious (small) enumeration in the LHS it is often
2300		% better simply to enumerate and check the RHS for every instance
2301		ground_bexpr(RHS), %print(not_exists_forall(Parameters,LHS,RHS)),nl,
2302		!,
2303		b_for_all_find_counter_example(Parameters,CParameters,CParameterTypes,Infos,LHS,RHS,WF).
2304		b_for_all_aux2(Parameters,CParameters,CParameterTypes,Infos,LHS,RHS,WF) :-
2305	?	parameter_list_cardinality(Parameters,ParCard),
2306		peel_implications(Parameters,ParCard,LHS,RHS, LHS2,RHS2),
2307	?	b_for_all_aux3(Parameters,ParCard,CParameters,CParameterTypes,Infos,LHS2,RHS2,WF).
2308
2309		b_for_all_aux3(Parameters,ParCard,CParameters,CParameterTypes,Infos,LHS,RHS,WF) :-
2310		%large_domain(Parameters,ParCard,LHS),
2311		is_infinite_or_very_large_explicit_set(closure(CParameters,CParameterTypes,LHS),10000000),
2312		% the domain is so large that we cannot possibly check all instances
2313		% 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)
2314		!,
2315		perfmessage(forall,'Large forall domain: ',ParCard,Infos),
2316		ground_bexpr_check(LHS,LG),
2317		ground_bexpr_check(RHS,RG),
2318		when((nonvar(LG),nonvar(RG)),
2319		b_for_all_find_counter_example(Parameters,CParameters,CParameterTypes,Infos,LHS,RHS,WF)
2320		).
2321		b_for_all_aux3(Parameters,ParCard,_CP,_,Infos,LHS,RHS,WF) :-
2322		if(expand_forall_quantifier(Parameters,LHS,RHS,Infos,WF,ReificationVariable),
2323		(
2324		perfmessage(good(forall),'Reified forall by expanding into conjunction: ',LHS),
2325		ReificationVariable=pred_true),
2326		( % print(normal_forall(Parameters)),nl,
2327		b_generate_for_all_list_domain1(Parameters,ParCard,LHS,RHS,[],[],AllSolList,NewRHS,WF),
2328		% now check every instance of the expanded domain (AllSolList):
2329	?	expand_forall1(AllSolList,NewRHS,Parameters,WF)
2330		)).
2331
2332
2333		% a treatment of for all where we look for counter examples satisfying LHS & not(RHS)
2334		b_for_all_find_counter_example(Parameters,CParameters,CParameterTypes,Infos,LHS,RHS,WF) :-
2335		% if LHS is Parameters: avl_set(V) then we probably should not apply this rule ?
2336		create_negation(RHS,NegRHS),
2337		conjunct_predicates_with_pos_info(LHS,NegRHS,Pred0),
2338		% format('looking for: ~w ',[CParameters]), translate:print_bexpr(LHS),nl, translate:print_bexpr(NegRHS),nl,
2339		perfmessage(good(forall),translating_forall_into_not_exists(CParameters),LHS),
2340		add_texpr_infos(Pred0,[quantifier_kind(forall)],ClosureBody1), % for call_stack
2341		init_quantifier_wait_flag(WF,not(forall),Parameters,ParValues,Infos,LocalWF), % relevant for test 1904
2342		not_with_enum_warning_and_possible_delay(
2343		(custom_explicit_sets:b_test_closure(CParameters,CParameterTypes,ClosureBody1,ParValues,negative,LocalWF),
2344		perfmessage_bexpr(forall,forall_counter_example(CParameters,ParValues),LHS)
2345		),LocalWF, WF, forall(CParameters), Infos).
2346
2347		:- use_module(library(timeout),[time_out/3]).
2348		not_with_enum_warning_and_possible_delay(C,WF,OuterWF,PP,Span) :-
2349		get_preference(disprover_mode,true),
2350		% in disprover mode we do not track WD errors, no need to start_attach_inner_abort_errors
2351		!,
2352		% delay potentially expensive quantifications in the hope of finding other contradictions earlier
2353		if( (time_out(not_with_enum_warning(C,WF,PP,Span),20,TRes),TRes \== time_out),
2354		copy_wfe_from_inner_if_necessary(WF,OuterWF),
2355		(get_wait_flag(2,not_with_enum_warning_and_possible_delay,OuterWF,LWF), % which priority to use ??
2356		debug_println(19,delay_not_in_disprover_mode),
2357		not_with_enum_warning_delay(C,LWF,WF,OuterWF,PP,Span))).
2358		not_with_enum_warning_and_possible_delay(C,WF,OuterWF,PP,Span) :-
2359		start_attach_inner_abort_errors(Level,not_with_enum_warning),
2360		call_cleanup(not_with_enum_warning(C,WF,PP,Span),
2361		re_attach_pending_inner_abort_errors(Level,OuterWF,_)),
2362		copy_wfe_from_inner_if_necessary(WF,OuterWF).
2363
2364
2365		:- block not_with_enum_warning_delay(?,-,?,?,?,?).
2366		not_with_enum_warning_delay(C,_,WF,OuterWF,PP,Span) :-
2367		debug_println(19,trigger_not_with_enum_warning_delay),
2368		not_with_enum_warning(C,no_wf_available,PP,Span),
2369		copy_wfe_from_inner_if_necessary(WF,OuterWF).
2370
2371		:- use_module(avl_tools,[quick_avl_approximate_size/2]).
2372		obvious_enumeration(LHS,[Id]) :- % TO DO : allow multiple ids
2373		% TO DO: unify with is_for_all_set_membership_predicate code below
2374		TLHSMembership = b(LHSMembership,_,_),
2375	?	member_conjunct(TLHSMembership,LHS,_),
2376		obvious_enum_aux(LHSMembership,Id).
2377
2378		obvious_enum_aux(member(TID,b(value(VAL),_,_)),ID) :- get_texpr_id(TID,ID),
2379		nonvar(VAL), VAL = avl_set(AVL), % TO DO: also support interval closures ?
2380		quick_avl_approximate_size(AVL,Size),
2381		Size<256.
2382		%obvious_enum_aux(equal(LHS,RHS),ID) :- % stillposes problem for test 231, investigate
2383		% ( get_texpr_id(LHS,ID) -> get_texpr_expr(RHS,value(_))
2384		% ; get_texpr_id(RHS,ID) -> get_texpr_expr(LHS,value(_))).
2385		% % TODO: do we need to accept integer(.),... literals?
2386
2387		% expands forall quantifier and thus enables that we also propagate from right to left
2388		% This helps for test 1397 (HandshakeSimple_TotFun)
2389		% TO DO: directly call the code which tries to expand a forall quantifier
2390		expand_forall_quantifier(Parameters,LHS,RHS,Infos,WF,ReificationVariable) :-
2391		(preferences:preference(use_smt_mode,true) -> true
2392		; preferences:preference(solver_strength,SS), SS>9), % sometimes contrapositive checking maybe not useful; see test 1368
2393		% TO DO: investigate and provide more principled heuristic
2394		b_interpreter_check:b_check_forall_wf(Parameters,LHS,RHS,Infos,[],[],WF,ReificationVariable).
2395
2396		% rewrite !(x,..).( TRUTH => (LHS2 => RHS2)) into !(x,...).(LHS2 => RHS2)
2397		peel_implications(Parameters,ParCard,LHS,RHS, NewLHS,NewRHS) :-
2398		%print(forall),nl, print(Parameters),nl,print(LHS),nl,
2399		% this patterns occurs often in Event-B translations to classical B
2400		LHS=b(truth,_,_),
2401		RHS=b(implication(LHS2,RHS2),_,_), % TO DO: maybe also accept nested forall and then add to Parameters?
2402		(is_inf_or_overflow_card(ParCard) -> true ; ParCard>50),
2403		% larger bound than below: maybe user explicitly wants to expand it
2404		!,
2405		peel_implications(Parameters,ParCard,LHS2,RHS2, NewLHS,NewRHS).
2406		peel_implications(_,_,LHS,RHS, LHS,RHS).
2407
2408		b_generate_for_all_list_domain_nolwf(Parameters,LHS,RHS,LS,S,ForAllDomain,NewRHS,WF) :-
2409	?	parameter_list_cardinality(Parameters,ParCard),
2410		peel_implications(Parameters,ParCard,LHS,RHS, LHS2,RHS2),
2411		b_generate_for_all_list_domain1(Parameters,ParCard,LHS2,RHS2,LS,S,OForAllDomain,NewRHS,WF),
2412		optlist_to_list(OForAllDomain,ForAllDomain). % resolve any optional_value/2 items
2413
2414		% generate the domain of a Universally Quantified Formula as a list
2415		b_generate_for_all_list_domain1(Parameters,_ParCard,LHS,RHS,LS,S,ForAllDomain,NewRHS,WF) :-
2416		% optimized treatment for formulas of the form !x.(x:S => RHS) or !(x,y).(x|->y:S => RHS)
2417		% to do: expand to more formulas, such as !(x,y).(x:S & y:T => RHS)
2418		% or !(x,y,z).( (x|->y:S & y|->z:S) => RHS)
2419		% 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))
2420		% or we could try and reify set membership for small domains and trigger implication
2421		is_for_all_set_membership_predicate(LHS,Parameters,Set,Pattern,ParameterValues),!,
2422		perfmessages_bexpr_call(good(forall),['Detected forall set membership over ',Ps,': '],
2423		LHS,bsyntaxtree:def_get_texpr_ids(Parameters,Ps)),
2424		NewRHS=RHS,
2425		b_generate_set_for_all_domain(Set,LS,S,Pattern,ParameterValues,ForAllDomain,WF).
2426		b_generate_for_all_list_domain1(Parameters,ParCard,LHS,RHS,LS,S,ForAllDomain,NewRHS,WF) :-
2427		b_generate_forall_closure(Parameters,LHS,LS,S,Closure,WF), % POSSIBLY NO NEED TO COMPILE
2428		b_generate_for_all_domain2(Closure,Parameters,ParCard,LHS,RHS,ForAllDomain,NewRHS,WF).
2429
2430		b_generate_for_all_domain2(Closure,_Parameters,_,LHS,RHS,ForAllDomain,NewRHS,WF) :-
2431		(LHS=b(truth,pred,_) ; ground_value(Closure)),
2432		!, NewRHS=RHS, % nl,print('FORALL EXPAND: '),(ground_value(Closure) -> print(ground(_Parameters)),nl, print_bexpr(LHS),nl ; print('NONGROUND!!'),nl,print_bexpr(RHS),nl), %%
2433		b_expand_closure_forall_to_list(Closure,ForAllDomain,WF).
2434		b_generate_for_all_domain2(_,Parameters,_,LHS,RHS,ForAllDomain,NewRHS,WF) :-
2435		is_a_conjunct(LHS,_,_), % otherwise we have already checked for set_membership above !
2436		LHS_Membership = b(member(_,_),_,_), % TO DO: also allow conjuncts
2437	?	member_conjunct(LHS_Membership,LHS,RestLHS),
2438		% !(x). ( x:Set & RestLHS => RHS) ---> !(x).(x:Set => (RestLHS => RHS))
2439		is_for_all_set_membership_predicate(LHS_Membership,Parameters,Set,Pattern,ParameterValues),
2440	?	max_cardinality_ok_for_expansion(Set,100,[],[]), % TO DO: simplify LS,S argument <----
2441		!,
2442		% as we expand Set without constraining RHS predicate, check if this is ok
2443		% indeed maximum cardinality of Set could be infinite !! !x.(x:NATURAL1 & x<N => P)
2444		% print('Splitting for all conjunct: '), print(Parameters),nl, print_bexpr(LHS_Membership),nl,print_bexpr(RestLHS),nl, %%
2445		perfmessage_bexpr(good(forall),'Splitting LHS of forall: ',LHS),
2446		NewRHS = b(implication(RestLHS,RHS),pred,[]), % TO DO: extract & join info
2447		b_generate_set_for_all_domain(Set,[],[],Pattern,ParameterValues,ForAllDomain,WF).
2448		b_generate_for_all_domain2(Closure,_Parameters,ParCard,LHS,RHS,ForAllDomain,NewRHS,WF) :-
2449		(is_inf_or_overflow_card(ParCard) -> true ; ParCard>8),
2450		!,
2451		NewRHS=RHS, write(no_opt),nl,
2452		perfmessage_bexpr(forall,'No optimisations applicable to forall (will delay until all variables are bound): ',LHS),
2453		% maybe we should generate this message only if ForAllDomain is var ?
2454		b_expand_closure_forall_to_list(Closure,ForAllDomain,WF).
2455		b_generate_for_all_domain2(_Closure,Parameters,ParCard,LHS,RHS,ForAllDomain,NewRHS,WF) :-
2456		NewLHS=b(truth,pred,[]), NewRHS=b(implication(LHS,RHS),pred,[]),
2457		b_generate_forall_closure(Parameters,NewLHS,[],[],Closure,WF),
2458		perfmessages_bexpr(good(forall),['Expanding forall with finite parameter type, card = ',ParCard,': '],LHS),
2459		b_expand_closure_forall_to_list(Closure,ForAllDomain,WF).
2460
2461		% code to decide whether a for all should be expanded if the
2462		% predicate contains a set membership predicate : !x.( (P & x:S & P') => Q)
2463		max_cardinality_ok_for_expansion(b(Expr,Type,_Info),Limit,LS,S) :- % which value to choose for Limit ??
2464	?	kernel_objects:max_cardinality(Type,TypeCard),
2465		( (number(TypeCard),TypeCard =< Limit) -> true ;
2466		max_cardinality_ok_for_expansion2(Expr,Limit,TypeCard,LS,S)).
2467
2468		max_cardinality_ok_for_expansion1(b(E,_,_),Limit,TC,LS,S) :-
2469		max_cardinality_ok_for_expansion2(E,Limit,TC,LS,S).
2470
2471		:- use_module(custom_explicit_sets,[efficient_card_for_set/3]).
2472
2473		max_cardinality_ok_for_expansion2(set_extension(E),Limit,_TC,_,_) :- !, length(E,Len), Len =< Limit.
2474		max_cardinality_ok_for_expansion2(interval(Up,Low),Limit,_TC,LS,S) :- !,
2475		get_integer(UpI,Up,LS,S), get_integer(LowI,Low,LS,S),
2476		UpI-LowI<Limit.
2477		max_cardinality_ok_for_expansion2(integer_set(GS),Limit,_TC,_LS,_S) :- !, b_global_set_cardinality(GS,Card),
2478		number(Card), Card =< Limit.
2479		max_cardinality_ok_for_expansion2(set_subtraction(A,_),Limit,TC,LS,S) :- !,
2480		max_cardinality_ok_for_expansion1(A,Limit,TC,LS,S).
2481		max_cardinality_ok_for_expansion2(image(RelA,_),Limit,TC,LS,S) :- !,
2482		max_cardinality_ok_for_expansion1(RelA,Limit,TC,LS,S).
2483		max_cardinality_ok_for_expansion2(function(_RelA,_),_Limit,_TC,_LS,_S) :- !,
2484		fail. % TO DO: we should look at the size of the range elements
2485		% max_cardinality_ok_for_expansion1(_RelA,_Limit,_TC,_LS,_S).
2486		max_cardinality_ok_for_expansion2(intersection(A,B),Limit,TC,LS,S) :- !,
2487		(max_cardinality_ok_for_expansion1(A,Limit,TC,LS,S) -> true ; max_cardinality_ok_for_expansion1(B,Limit,TC,LS,S)).
2488		max_cardinality_ok_for_expansion2(union(A,B),Limit,TC,LS,S) :- !,
2489		max_cardinality_ok_for_expansion1(A,Limit,TC,LS,S), max_cardinality_ok_for_expansion1(B,Limit,TC,LS,S).
2490		max_cardinality_ok_for_expansion2(range(A),Limit,TC,LS,S) :- !,
2491		max_cardinality_ok_for_expansion1(A,Limit,TC,LS,S).
2492		max_cardinality_ok_for_expansion2(domain(A),Limit,TC,LS,S) :- !,
2493		max_cardinality_ok_for_expansion1(A,Limit,TC,LS,S).
2494		max_cardinality_ok_for_expansion2(domain_restriction(_A,B),Limit,TC,LS,S) :- !,
2495		max_cardinality_ok_for_expansion1(B,Limit,TC,LS,S). % note: finite A does not guarantee finite result
2496		max_cardinality_ok_for_expansion2(domain_subtraction(_A,B),Limit,TC,LS,S) :- !,
2497		max_cardinality_ok_for_expansion1(B,Limit,TC,LS,S).
2498		max_cardinality_ok_for_expansion2(range_restriction(A,_B),Limit,TC,LS,S) :- !,
2499		max_cardinality_ok_for_expansion1(A,Limit,TC,LS,S). % note: finite B does not guarantee finite result
2500		max_cardinality_ok_for_expansion2(range_subtraction(A,_B),Limit,TC,LS,S) :- !,
2501		max_cardinality_ok_for_expansion1(A,Limit,TC,LS,S).
2502		max_cardinality_ok_for_expansion2(direct_product(A,B),Limit,TC,LS,S) :- !,
2503		max_cardinality_ok_for_expansion2(cartesian_product(A,B),Limit,TC,LS,S).
2504		max_cardinality_ok_for_expansion2(parallel_product(A,B),Limit,TC,LS,S) :- !,
2505		max_cardinality_ok_for_expansion2(cartesian_product(A,B),Limit,TC,LS,S).
2506		max_cardinality_ok_for_expansion2(cartesian_product(A,B),Limit,TC,LS,S) :- !,
2507		ILimit is Limit//2, ILimit>0, %use sqrt ?
2508		max_cardinality_ok_for_expansion1(A,ILimit,TC,LS,S),
2509		max_cardinality_ok_for_expansion1(B,ILimit,TC,LS,S).
2510		max_cardinality_ok_for_expansion2(value(S),Limit,_TC,_LS,_S) :- !,
2511		get_max_card_for_value(S,MaxCard),
2512		MaxCard =< Limit.
2513		max_cardinality_ok_for_expansion2(identifier(_ID),_Limit,TC,_LS,_S) :- !, number(TC).
2514		% TO DO: check if ID is fully defined; if so use card else accept as it will
2515		% probably be represented by a list and the forall constraints could be useful in finding ID's value
2516		% 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?
2517		max_cardinality_ok_for_expansion2(external_function_call(_,_),_,_,_,_) :- !,fail.
2518		max_cardinality_ok_for_expansion2(lazy_lookup_expr(_),_,_,_,_) :- !,fail.
2519		max_cardinality_ok_for_expansion2(record_field(_,_),_Limit,_TC,_LS,_S) :- !, fail.
2520		max_cardinality_ok_for_expansion2(E,Limit,TC,_LS,_S) :- functor(E,F,N),
2521		print(unknown_max_card(F/N,Limit,TC)),nl,fail.
2522
2523
2524		:- use_module(kernel_cardinality_attr,[clpfd_card_domain_for_var/3]).
2525
2526		get_max_card_for_value(S,MaxCard) :- var(S), !,
2527		clpfd_card_domain_for_var(S,_,Max),
2528		number(Max),
2529		MaxCard=Max.
2530		get_max_card_for_value([],R) :- !, R=0.
2531		get_max_card_for_value([_|T],R) :- !,get_max_card_for_value(T,TMax), R is TMax+1.
2532		get_max_card_for_value(S,Card) :- efficient_card_for_set(S,Card,C),!,
2533		call(C), number(Card).
2534
2535
2536		get_integer(X, b(Expr,integer,_),LS,S) :- get_integer2(Expr,X,LS,S).
2537		get_integer2(integer(X),X,_,_) :- number(X).
2538		get_integer2(identifier(Id),Val,LS,S) :- lookup_value(Id,LS,S,int(Val)), number(Val).
2539
2540		member_conjunct(Predicate,Conjunction,Rest) :-
2541		conjunction_to_list(Conjunction,List),
2542	?	select(Predicate,List,RestList),
2543		conjunct_predicates(RestList,Rest).
2544		% member_conjunct(Conj,Conj,b(truth,pred,[])). covered by case above
2545
2546		b_generate_set_for_all_domain(Set,LS,S,Pattern,ParameterValues,ForAllDomain,WF) :-
2547		b_compute_expression(Set,LS,S,EvSet,WF),
2548		expand_custom_set_to_list_wf(EvSet,ESet,_Done,b_generate_set_for_all_domain,WF),
2549		filter_and_convert_list_to_parameter_tuples(ESet,Pattern,ParameterValues,ForAllDomain).
2550
2551
2552		% check if it is a predicate of the form x:S or x:Sx & y:Sy ... which we can optimize
2553		% (i.e. compute SET before all values inside it are fully known)
2554		is_for_all_set_membership_predicate(LHS,Parameters,Set,Pattern,ParameterValues) :-
2555		% print('CHECK FORALL : '), translate:print_bexpr(LHS),nl,nl,
2556		get_texpr_ids(Parameters,ParIDs), % TO DO: call get_texpr_ids before
2557		same_length(ParIDs,ParameterValues),
2558		is_for_all_set_membership_predicate2(LHS,ParIDs,ParIDs,UnmatchedParIDs,Set,Pattern,ParameterValues,_UPV),
2559		UnmatchedParIDs=[].
2560
2561		% TODO: maybe also deal with existential quantifiers #x.(x|->y:Set) -> in Pattern x becomes free var
2562		is_for_all_set_membership_predicate2(LHS,All,ParIDs,UnmatchedParIDs,Set,Pattern,ParameterValues,UPV) :-
2563		is_member_test(LHS,Element,Set),
2564		!,
2565		identifiers_not_used_in_bexp(All,Set),
2566		convert_to_prolog_pattern_match(Element,ParIDs,UnmatchedParIDs,Pattern,ParameterValues,UPV).
2567		% TO DO: also allow failing pattern matches ?!; at least when splitting
2568		is_for_all_set_membership_predicate2(LHS,All,ParIDs,ParIDs2,Set,
2569		(Pat1,Pat2),ParameterValues,UPV) :-
2570		is_a_conjunct(LHS,LHS1,LHS2), % we could have something of the form x:Sx & y:Sy ...
2571		Set = b(cartesian_product(Set1,Set2),couple(T1,T2),[]),
2572		is_for_all_set_membership_predicate2(LHS1,All,ParIDs, ParIDs1,Set1,Pat1,ParameterValues,PV1),
2573		get_texpr_type(Set1,T1),
2574		!,
2575		is_for_all_set_membership_predicate2(LHS2,All,ParIDs1,ParIDs2,Set2,Pat2,PV1,UPV),
2576		get_texpr_type(Set2,T2).
2577
2578		% TO DO: maybe use a more general test to be reused in other places
2579		is_member_test(b(P,_,_),Element,Set) :- is_member_test_aux(P,Element,Set).
2580		is_member_test_aux(member(Element,Set),Element,Set).
2581		% also detect equalities: important for tests 28,29 after b_compiler can introduce equalities for singleton set memberships
2582		is_member_test_aux(equal(Element,SetVal),Element,Set) :- % TO DO : also other direction + other kinds of values ?
2583		SetVal = b(value(SV),T,I),
2584		Set = b(value([SV]),set(T),I).
2585
2586		identifiers_not_used_in_bexp(IDList,Expr) :-
2587		find_identifier_uses(Expr,[],Used),
2588		id_check(IDList,Used).
2589		id_check([],_).
2590		id_check([ID|T],Used) :-
2591		nonmember(ID,Used), !,
2592		id_check(T,Used).
2593
2594		% check if an expression can be converted to a Prolog linear unification/pattern match
2595		% give an list of free identifiers IDS
2596		convert_to_prolog_pattern_match(b(E,_,_),IDS,OutIDS,Pattern,VarsIn,VarsOut) :-
2597		convert_to_prolog_pattern_match2(E,IDS,OutIDS,Pattern,VarsIn,VarsOut).
2598
2599		convert_to_prolog_pattern_match2(identifier(ID),IDsIn,IDsOut,PatVariable,VarsIn,VarsOut) :-
2600		% check that the identifier is in the list of quantified variables and thus unbound
2601		!,
2602	?	(nth1(Nr,IDsIn,ID,IDsOut)
2603		-> nth1(Nr,VarsIn,PatVariable,VarsOut) % put fresh PatVariable in the Pattern
2604		),!.
2605		convert_to_prolog_pattern_match2(couple(ID1,ID2),IDS,OutIDS,Pattern,VarsIn,VarsOut) :-
2606		Pattern = (Pat1,Pat2),
2607		convert_to_prolog_pattern_match(ID1,IDS,RemIDS,Pat1,VarsIn,VarsInt),
2608		convert_to_prolog_pattern_match(ID2,RemIDS,OutIDS,Pat2,VarsInt,VarsOut).
2609		convert_to_prolog_pattern_match2(value(V),IDsIn,IDsOut,Pattern,VarsIn,VarsOut) :-
2610		can_be_used_for_unification(V), % check if we can use Prolog unification for equality
2611		!, Pattern=V, IDsOut=IDsIn, VarsIn=VarsOut.
2612		% TO DO: records?
2613
2614		% a pattern match code to be used with above; ensure we do not instantiate values
2615		pattern_match(PatVar,Val,Res) :- var(PatVar),!,PatVar=Val, Res=pred_true. % we have a free pattern variable
2616		pattern_match((Pat1,Pat2),(V1,V2),Res) :- !,
2617		pattern_match(Pat1,V1,R1), conjoin_simple(R1,R2,Res),
2618		pattern_match(Pat2,V2,R2).
2619		pattern_match(GroundPatVal,Val,Res) :- % we have a value that can_be_used_for_unification
2620		when( ?=(GroundPatVal,Val), (GroundPatVal=Val -> Res=pred_true ; Res=pred_false)).
2621
2622		:- block conjoin_simple(-,?,?). % TO DO: also allow second arg to unblock
2623		conjoin_simple(pred_true,X,X).
2624		conjoin_simple(pred_false,_,pred_false).
2625
2626		% similar to get_template(V,T,[])
2627		% but more restricted; we only accept those values where equality corresponds to Prolog unification
2628		% get_template is different and can assume normalized values, e.g., for empty set
2629		% pairs are treated above in convert_to_prolog_pattern_match2
2630		can_be_used_for_unification(V) :- var(V),!,fail.
2631		can_be_used_for_unification(int(V)) :- integer(V).
2632		can_be_used_for_unification(string(S)) :- ground(S).
2633		can_be_used_for_unification(fd(S,T)) :- ground(S), ground(T).
2634		can_be_used_for_unification(pred_false).
2635		can_be_used_for_unification(pred_true).
2636		can_be_used_for_unification(term(floating(F))) :- number(F).
2637		% TODO: simple atomic freevalues?
2638
2639
2640		% take a list and a pattern and filter the values that do not match the Pattern
2641		% Unification with the Pattern also instantiates the ParameterValues
2642		% used for triggering and instantiating right-hand-side of forall: !x.(x:Set => RHS)
2643		% TODO: Instead of converting to a Prolog Unification we could use kernel_equality instead of pattern_match
2644		% but this is not obvious, as the pattern contains free variables and equality would never return true
2645		% we would need to apply kernel_equality only to the ground pattern parts
2646		:- block filter_and_convert_list_to_parameter_tuples(-,?,?,?).
2647		filter_and_convert_list_to_parameter_tuples([],_,_,[]).
2648		filter_and_convert_list_to_parameter_tuples([H|T],Pattern,ParameterValues,Res) :-
2649		copy_term((Pattern,ParameterValues),(CPat,CPV)),
2650		pattern_match(CPat,H,PredRes), % check if pattern matches new element H in set; careful not to instantiate H
2651	?	filter_and_convert_list_to_parameter_tuples_aux(PredRes,CPV,T,Pattern,ParameterValues,Res).
2652
2653		:- block filter_and_convert_list_to_parameter_tuples_aux(-,?,-,?,?,?).
2654		filter_and_convert_list_to_parameter_tuples_aux(PredRes,CPV,T,Pattern,ParameterValues,Res) :-
2655		var(PredRes),!, % we cannot decide yet whether the optional value is to be used or not
2656		Res = [optional_value(CPV,PredRes)|RT], % create constructor for map_optlist or similar
2657		filter_and_convert_list_to_parameter_tuples(T,Pattern,ParameterValues,RT).
2658		filter_and_convert_list_to_parameter_tuples_aux(PredRes,CPV,T,Pattern,ParameterValues,Res) :-
2659		(PredRes = pred_true % we have a match, universal quantifier applies to H
2660		-> Res = [CPV|RT]
2661		; % element of set does not match pattern; universal quantifier does not apply
2662		% ProB used to only accept non-failing pattern matches;
2663		% now we also accept tuples with static parts where Prolog unification can fail
2664		Res=RT
2665		),
2666	?	filter_and_convert_list_to_parameter_tuples(T,Pattern,ParameterValues,RT).
2667
2668		:- use_module(tools,[map_optlist/2,optlist_to_list/2]).
2669		:- use_module(library(lists),[maplist/3]).
2670		expand_forall1(OList,RHS,Parameters,WF) :-
2671		ground_bexpr(RHS), % because compiled this means we cannot do any constraint propagation on variables in RHS
2672		optlist_to_list(OList,List),
2673		ground_value(List), % ditto here: no variables on which we could do constraint propagation
2674		%% preferences:get_preference(double_evaluation_when_analysing,false), % causes test 1112 to fail TO DO:fix
2675		% otherwise we do not have a real redundancy wrt to not exists check
2676		debug_println(15,ground_forall_translating_into_not_exists(Parameters)),
2677		!,
2678		init_quantifier_wait_flag(WF,forall,Parameters,ParResult,unknown,LocalWF),
2679		% Advantage over treatment below: NegRHS is interpreted only once
2680		% but we cannot provide any instantiations and there must not be any links with variables outside of the forall !!
2681		create_negation(RHS,NegRHS),
2682		not_with_enum_warning( (
2683		b_interpreter:test_forall_instance(NegRHS,Parameters,LocalWF,negative,ParResult),
2684		% test_forall_instance can fail; if inconsistency detected in WF0
2685		kernel_waitflags:ground_det_wait_flag(LocalWF),
2686		member(ParResultInList,List), % check the body for every solution
2687		lists:maplist(kernel_objects:equal_object,ParResultInList,ParResult), % match params with solutions of domain
2688		kernel_waitflags:ground_wait_flags(LocalWF)
2689		), LocalWF, forall(Parameters), RHS
2690		).
2691		expand_forall1(List,RHS,Parameters,WF) :-
2692		% blocking version of maplist which also filters out some optional_value/2 terms:
2693	?	map_optlist(b_interpreter:test_forall_instance(RHS,Parameters,WF,positive),List).
2694
2695		% test RHS of a forall for a particular valuation ParResult of the Parameters
2696		test_forall_instance(RHS,Parameters,WF,NegationContext,ParResult) :-
2697		LocalState=[],State=[],
2698	?	if(set_up_typed_localstate(Parameters,ParResult,_TypedVals,LocalState,NewLocalState,NegationContext),
2699		true,
2700		(nl,print(set_up_typed_localstate_failed(Parameters,ParResult,_,LocalState,NewLocalState)),nl,
2701		% it can happen that ParResult has constraints on it and that setting up the typing info detects the error
2702		% add_internal_error('Call failed: ', set_up_typed_localstate(Parameters,ParResult,_,LocalState,NewLocalState)),
2703		fail)),
2704	?	b_optimized_b_test_instance(RHS,NewLocalState,State,WF).
2705
2706		reification_relevant_for_op(implication(_,_)).
2707		reification_relevant_for_op(equivalence(_,_)).
2708		reification_relevant_for_op(disjunct(_,_)).
2709		% TODO: maybe check if a conjunct contains implication
2710		% relevant for example for: n=2000 & f:1..n-->BOOL & !i.(i:2..n => (f(i)=TRUE =>f(i-1)=FALSE)) & f(1)=TRUE
2711
2712		b_optimized_b_test_instance(RHS,NewLocalState,State,WF) :-
2713		get_texpr_expr(RHS,RE), reification_relevant_for_op(RE), % we will attempt reification
2714		attempt_reification,
2715		\+ always_well_defined(RHS), % this will prevent reification
2716		!,
2717		% try and compile in the hope that now the WD issue disappears:
2718		b_compiler:b_optimize(RHS,[],NewLocalState,State,NewRHS,WF),
2719		b_test_boolean_expression(NewRHS,NewLocalState,State,WF).
2720		b_optimized_b_test_instance(RHS,NewLocalState,State,WF) :-
2721	?	b_test_boolean_expression(RHS,NewLocalState,State,WF).
2722		% using b_test_inner_boolean_expression considerably slows down NQueens, Sudoku,...
2723		% WF=InnerWF. /* give the boolean expression a chance to do ground propagations first */
2724
2725
2726		% use this when the test boolean expression could be called with WF0 already set
2727		% give the inner expression a chance to do the deterministic stuff first
2728		b_test_inner_boolean_expression(Pred,LocalState,State,WF) :-
2729		kernel_waitflags:clone_wait_flags_from1(WF,GroundUponFinish,WF2),
2730		% set WF0 to variable to propagate deterministic infos first:
2731	?	b_test_boolean_expression(Pred,LocalState,State,WF2),
2732	?	kernel_waitflags:clone_wait_flags_from1_finish(WF,GroundUponFinish,WF2).
2733		% the same for testing negation of a predicate:
2734		b_not_test_inner_boolean_expression(Pred,LocalState,State,WF) :-
2735		kernel_waitflags:clone_wait_flags_from1(WF,GroundUponFinish,WF2),
2736		% set WF0 to variable to propagate deterministic infos first:
2737		b_not_test_boolean_expression(Pred,LocalState,State,WF2),
2738		kernel_waitflags:clone_wait_flags_from1_finish(WF,GroundUponFinish,WF2).
2739
2740		/* now the same as above; but without converting list of values into pairs */
2741		:- assert_pre(b_interpreter:b_expand_closure_forall_to_list(Closure,_Result,_WF),
2742		(nonvar(Closure), custom_explicit_sets:is_closure(Closure,_Parameters,_ParameterTypes,ClosureBody),
2743		nonvar(ClosureBody),
2744		bsyntaxtree:check_if_typed_predicate(ClosureBody))).
2745		:- assert_post(b_interpreter:b_expand_closure_forall_to_list(_Closure,Result,_WF),
2746		b_interpreter:value_type(Result)).
2747		b_expand_closure_forall_to_list(Closure,Result,WF) :- nonvar(Closure),
2748		Closure = closure(Parameters,ParameterTypes,ClosureBody),
2749		!,
2750		% print('Expand closure forall: '), translate:print_bexpr(ClosureBody),nl,
2751		% at the moment we may wait too long before expanding this closure
2752		% 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 ?
2753		(performance_monitoring_on,
2754		term_variables(ClosureBody,Vars),
2755		Vars \= []
2756		->
2757		perfmessagecall(delaying_forall(Parameters,vars(Vars),out(ParValues)),
2758		translate:print_bexpr(ClosureBody),ClosureBody)
2759		; true),
2760		ground_bexpr_check(ClosureBody,BodyGround),
2761		add_texpr_infos(ClosureBody,[quantifier_kind(forall)],ClosureBody1), % for call_stack
2762		delay_setof_list_wf( ParValues,
2763		%% (print_bt_message(expanding_forall_closure(Parameters,ClosureBody,ParValues)), %%
2764		custom_explicit_sets:b_test_closure(Parameters,ParameterTypes,ClosureBody1,
2765		ParValues,all_solutions,WF)
2766		%% ,print_bt_message(expanded(Parameters,ParValues)) ) %%
2767		,
2768		Result,
2769		BodyGround,WF).
2770		b_expand_closure_forall_to_list(Closure,Result,WF) :-
2771		add_internal_error('Illegal Call: ', b_expand_closure_forall_to_list(Closure,Result,WF)),
2772		fail.
2773
2774
2775		:- assert_pre(b_interpreter:set_up_typed_localstate(V,S,_), (list_skeleton(V),list_skeleton(S))).
2776		:- assert_post(b_interpreter:set_up_typed_localstate(_,_,R),list_skeleton(R)).
2777
2778		set_up_typed_localstate(Identifiers,InState,OutState) :-
2779	?	set_up_typed_localstate(Identifiers,_FreshVars,_TypedVals,InState,OutState,positive).
2780
2781		:- use_module(b_enumerate,[construct_typedval_infos/4]).
2782		set_up_typed_localstate([],[],[],State,State,_).
2783		set_up_typed_localstate([Identifier|IdRest],[Val|ValRest],[typedval(Val,Type,Var,TINFO)|TRest],
2784		% TO DO: add info field to typedval: source_span, and lambda_result/do_not_enumerate infos
2785		InState,OutState,NegationContext) :-
2786		% The other way round (first add Identfier, then IdRest) would be more efficient,
2787		% but we do it this way to keep compatibility with a previous version.
2788		% In specfile:compute_operation_effect, the arguments of an operation are in the same order than in the store
2789	?	set_up_typed_localstate(IdRest,ValRest,TRest,InState,InterState,NegationContext),
2790		def_get_texpr_id(Identifier,Var), get_texpr_type(Identifier,Type),
2791		get_texpr_info(Identifier,Info),
2792		triggers_enum_warning(Var,Type,Info,NegationContext,TriggersEnumWarning),
2793		get_texpr_info(Identifier,Infos),construct_typedval_infos(Var,Infos,TriggersEnumWarning,TINFO),
2794	?	add_typed_var_to_localstate(Var,Val,Type,InterState,OutState).
2795
2796		% same version; but with list of atomic ids and list of types
2797		set_up_typed_localstate2([],[],_,[],[],State,State,_).
2798		set_up_typed_localstate2([Var|IdRest],[Type|TyRest],Infos,[Val|ValRest],[typedval(Val,Type,Var,TINFO)|TRest],
2799		InState,OutState,NegationContext) :-
2800		% The other way round (first add Identfier, then IdRest) would be more efficient,
2801		% but we do it this way to keep compatibility with a previous version.
2802		% In specfile:compute_operation_effect, the arguments of an operation are in the same order than in the store
2803	?	set_up_typed_localstate2(IdRest,TyRest,Infos,ValRest,TRest,InState,InterState,NegationContext),
2804		triggers_enum_warning(Var,Type,Infos,NegationContext,TriggersEnumWarning),
2805		construct_typedval_infos(Var,Infos,TriggersEnumWarning,TINFO),
2806	?	add_typed_var_to_localstate(Var,Val,Type,InterState,OutState).
2807
2808		% possible values for NegationContext: positive, negative, all_solutions
2809		triggers_enum_warning(Id,Type,Info,all_solutions,Res) :- !,
2810		Res = trigger_throw(b(identifier(Id),Type,Info)).
2811		%triggers_enum_warning(Id,_Type,Info,NegationContext,trigger_false(Id)) :- % no longer used
2812		% NegationContext=positive, % when negated then success will occur if all possibilities have been tried out
2813		% memberchk(introduced_by(exists),Info),
2814		% %%((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),
2815		% %% The Disprover now checks whether unfixed_deferred sets were involved; keeping track of implicit enumerations of %deferred sets is just too difficult
2816		% !.
2817		triggers_enum_warning(Id,Type,Info,_,trigger_true(b(identifier(Id),Type,Info))).
2818
2819
2820		add_typed_var_to_localstate(Var,Val,Type,InState,OutState) :-
2821		add_var_to_localstate(Var,Val,InState,OutState),
2822		%%when(ground(Val), (print(' ++ '),print(Var),print(' ---> '), print(Val),nl)),
2823	?	kernel_objects:basic_type(Val,Type). %% ,print(ok(Val)),nl.
2824
2825		/*
2826		xxb_test_exists(Parameters,Condition,Infos,LocalState,State,WF) :-
2827		b_check_boolean_expression(b(exists(Parameters,Condition),pred,Infos),LocalState,State,WF,NR),
2828		get_exists_used_ids(Parameters,Condition,Infos,Used),lookup_values_if_vars(Used,LocalState,State,WaitVars),
2829		\+ ground(WaitVars),
2830		!,
2831		debug_println(9,unfolding_exists(Parameters)), print(unfolding(Parameters)),nl,
2832		%translate:print_bexpr(Condition),nl, print(State),nl, print(LocalState),nl,nl,
2833		NR=pred_true. %, print(set_res(pred_true)),nl.
2834		% 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
2835		*/
2836
2837		b_test_exists(Parameters,Condition,Infos,LocalState,State,WF) :-
2838		get_wait_flag0(WF,WF0),
2839	?	b_test_exists(WF0,Parameters,Condition,Infos,LocalState,State,WF).
2840
2841		:- block b_test_exists(-,?,?, ?,?,?,?).
2842		b_test_exists(_LWF,Parameters,Condition,Infos,LocalState,State,WF) :-
2843		if((attempt_reification, % what if there is a wd_condition attached to Condition?
2844		b_interpreter_check:b_check_exists_wf(Parameters,Condition,Infos,LocalState,State,WF,ReificationVariable)),
2845		% try and expand quantifiers of small cardinality; see also expand_forall_quantifier
2846		% tested in test 1452
2847		(debug_println(9,expanded_exists(Parameters)),
2848		ReificationVariable=pred_true),
2849	?	b_test_exists_wo_expansion(Parameters,Condition,Infos,LocalState,State,WF)).
2850
2851		%attempt_reification :- preferences:preference(use_clpfd_solver,true),!. % all tests seem to pass
2852		attempt_reification :- preferences:preference(use_smt_mode,true),!.
2853		attempt_reification :- preferences:preference(solver_strength,SS), SS>9.
2854		% TO DO: maybe take context into account: setup constants, becomes such, ... allow_skipping_over_components/reset_component_info(true)
2855
2856		:- use_module(kernel_tools,[bexpr_variables/2, value_variables/3]).
2857
2858		% we treat the existential quantifier without expansion into a disjuncition aka reification
2859		b_test_exists_wo_expansion(Parameters,Condition,Infos,LocalState,State,WF) :-
2860		%print(test_exists(Parameters,Infos)),nl,portray_waitflags(WF),nl,
2861	?	(preference(lift_existential_quantifiers,true) ; member(allow_to_lift_exists,Infos)),
2862		!, % we enumerate the exists normally; treat it just like an ordinary predicate
2863		% lifting may generate multiple solutions; but avoids delaying enumeration of quantified parameters
2864		% print('*Lifting existential quantifier: '), translate:print_bexpr(Condition),nl,
2865	?	set_up_typed_localstate(Parameters,ParaValues,TypedVals,LocalState,NewLocalState,positive),
2866		copy_wf_start(WF,b_test_exists_wo_expansion,CWF),
2867		opt_push_wait_flag_call_stack_quantifier_info(CWF,exists,Parameters,ParaValues,Infos,CWF2),
2868	?	b_test_boolean_expression(Condition,NewLocalState,State,CWF2),
2869		% often we do not need to enumerate TypedVals; they can be derived, but we could have #y.(y>x) and need to enum y
2870		b_tighter_enumerate_values_in_ctxt(TypedVals,Condition,CWF2),
2871	?	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)
2872		b_test_exists_wo_expansion(Parameters,Condition,Infos,LocalState,State,WF) :-
2873		get_exists_used_ids(Parameters,Condition,Infos,Used),
2874		% IT IS IMPORTANT THAT THE USED INFO IS CORRECT ; otherwise the WaitVars will be incorrect
2875		% The used_ids info does not include the Parameters of the existential quantifier !
2876	?	set_up_typed_localstate(Parameters,ParaValues,TypedVals,LocalState,NewLocalState,positive),
2877		lookup_values_if_vars(Used,LocalState,State,WaitVarsState), % TO DO: we could use b_compiler instead
2878		% What if the Condition was compiled and now contains a previously used_variable inside a closure/value ?
2879		%term_variables((Condition,WaitVarsState),WaitVars), % this can be expensive when we have large data values (see rule_RVF219/rule_RVF219_compo.mch)
2880		bexpr_variables(Condition,CondVars),
2881		value_variables(WaitVarsState,CondVars,WaitVars),
2882		% now determine which WaitVars are really worth waiting for, e.g., do not wait for res in #x.(x:E & ... res=min(f(x)))
2883		% relevant tests: 1868, 1194, 383, 1642, 1708, 1003, 1080, 1081, 1943
2884		(remove_ids_defined_by_equality(WaitVars,LocalState,State,Infos,RealWaitVars) -> RemovedVars=true
2885		; RealWaitVars = WaitVars, RemovedVars=false),
2886		opt_push_wait_flag_call_stack_quantifier_info(WF,exists,Parameters,ParaValues,Infos,WF2),
2887		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
2888	?	b_test_boolean_expression(Condition,NewLocalState,State,LocalWF), /* check Condition */
2889	?	ground_det_wait_flag(LocalWF), % print('det no contradiction'),nl,flush_output,
2890		b_tighter_enumerate_values_in_ctxt(TypedVals,Condition,LocalWF), % will not yet enumerate
2891		(% we could treat allow_to_lift_exists also here by setting ESWF=1; but 1162 then fails
2892		get_preference(data_validation_mode,true),
2893		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
2894		-> get_wait_flag(50000,b_test_exists(Parameters),WF,ESWF) % 100000 sufficient for test 1945; 869 for rule_CHAMPS in private_examples/ClearSy/2023
2895		; 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
2896		when((nonvar(ESWF);ground(RealWaitVars)),b_enumerate_exists(ESWF,RemovedVars,WaitVars,Parameters,Infos,LocalWF,WF)).
2897
2898
2899		:- use_module(tools,[remove_variables/3]).
2900		:- use_module(kernel_tools,[value_variables/2]).
2901		% if we have #x.( P & y = E(x)) we do not have to wait for y to be known
2902		remove_ids_defined_by_equality(WaitVars,LocalState,State,Infos,RealWaitVars) :- WaitVars \== [],
2903		memberchk(used_ids_defined_by_equality(Ideq),Infos),
2904		Ideq = [ID1|_], % currently we only look at one used_id defined by equality,
2905		% we could have #x.(P & y=E(z) & z=E(y)): TODO: improve computation in ast_cleanup
2906		(memberchk(bind(ID1,VAL),LocalState) -> true ; memberchk(bind(ID1,VAL),State)),
2907		value_variables(VAL,VARS),
2908		remove_variables(WaitVars,VARS,RealWaitVars),
2909		debug_println(9,removed_ids_def_by_equality(WaitVars,ID1,RealWaitVars)).
2910
2911
2912		b_enumerate_exists(ESWF,RemovedVars,WaitVars,Parameters,Infos,LocalWF,WF) :-
2913		%print(enum_exists(ESWF,RemovedVars,WaitVars,Parameters,LocalWF,WF)),nl,
2914		((RemovedVars=false,var(ESWF) ; % WaitVars guaranteed to be ground
2915		ground(WaitVars)) % TODO: replace this by an optimised version of ground check
2916		-> get_idle_flag(Parameters,WF,LWF),
2917		/* allow all other co-routines waiting on WaitVars to complete */
2918		/* Note however: if WF grounding as triggered two non-deterministic co-routines this
2919		will allow the other non-determinism to run first, duplicating the number of calls !
2920		This has been fixed by storing seperate waitflag variables for same prio in kernel_waitflags
2921		TODO: However, for enumeration of FD variables this might still happen and lead to duplication of
2922		calls to b_enumerate_exists_aux_ground
2923		*/
2924		%print(get_idle(Parameters,WaitVars)),nl, %kernel_waitflags:portray_waitflags(WF),nl,nl,
2925		b_enumerate_exists_aux_ground(LWF,WaitVars,Parameters,Infos,LocalWF,WF)
2926		; debug_println(9,semi_lifting_exists(ESWF,Parameters)),
2927		% add_message_wf(exists,'Semi-lifting exists:',Parameters,Parameters,WF),portray_waitflags(LocalWF),nl,
2928		kernel_waitflags:copy_waitflag_store(LocalWF,WF) % outer WF will now drive enumeration
2929		% Note: in case a LET has been moved inside and replaced this may lead to duplication
2930		).
2931
2932		:- if(environ(prob_safe_mode,true)).
2933		get_idle_flag(Parameters,WF,LWF) :- kernel_waitflags:get_idle_wait_flag(b_enumerate_exists(Parameters),WF,LWF),
2934		(var(LWF) -> true ; add_internal_error('Illegal idle waitflag for exists:',get_idle_flag(Parameters,WF,LWF))).
2935		:- else.
2936		get_idle_flag(Parameters,WF,LWF) :- kernel_waitflags:get_idle_wait_flag(b_enumerate_exists(Parameters),WF,LWF).
2937		:- endif.
2938
2939		:- block b_enumerate_exists_aux_ground(-,?,?,?,?,?).
2940		b_enumerate_exists_aux_ground(_,_WaitVars,Parameters,Infos,LocalWF,_WF) :-
2941		/* Note: this does a local cut: so it is important
2942		that all conditions are fully evaluated before performing the cut ; otherwise
2943		solutions will be lost */
2944		% print_bt_message('ENUMERATE EXISTS'(_Parameters)),nl, % portray_waitflags(_WF),
2945		if(ground_wait_flags_for_exists(Parameters,LocalWF),true,
2946		(perfmessage(exists,'Late bound exists failed: ',Parameters,Infos),fail)).
2947
2948
2949		ground_wait_flags_for_exists(Parameters,LocalWF) :-
2950	?	\+ enumeration_warning_occured_in_error_scope,
2951		get_current_error_scope(Level),
2952	?	\+ error_manager:throw_error(Level,_,_),
2953		!, % current scope is already clean, no need to enter a fresh one
2954		ground_wait_flags_for_exists2(Parameters,LocalWF,Level).
2955		ground_wait_flags_for_exists(Parameters,LocalWF) :-
2956		enter_new_clean_error_scope(Level),
2957		% Note: see {x|x:1..10 & #y.(y>x & y*y >10)} in test 2210:
2958		% we do not want to throw enum warnings even if the outer scope does in case a solution is found
2959		% 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
2960		call_cleanup(ground_wait_flags_for_exists2(Parameters,LocalWF,Level),
2961		exit_error_scope(Level,_,ground_wait_flags_for_exists)).
2962
2963		ground_wait_flags_for_exists2(_Parameters,LocalWF,Level) :-
2964	?	(ground_constraintprop_wait_flags(LocalWF)
2965		-> % local cut: one solution is sufficient.
2966		clear_enumeration_warning_in_error_scope(Level)
2967		% ; %print(fail),nl, % do not clear enumeration warnings fail
2968		).
2969
2970
2971		:- use_module(b_ast_cleanup,[check_used_ids_info/4]).
2972		get_exists_used_ids(Parameters,Condition,Infos,Used) :-
2973		preference(prob_safe_mode,true),!,
2974		(select(used_ids(Used),Infos,Rest)
2975		-> check_used_ids_info(Parameters,Condition,Used,exists), %% comment in to check used_ids field
2976		(member(used_ids(_),Rest)
2977		-> add_internal_error('Multiple used_ids info fields:',Parameters:Infos) ; true)
2978		;
2979		add_internal_error(
2980		'Expected information of used identifiers in exists information',Parameters:Infos),
2981		bsyntaxtree:find_identifier_uses(Condition, [], Used)
2982		).
2983		get_exists_used_ids(Parameters,Condition,Infos,Used) :-
2984	?	member(used_ids(Used),Infos) -> true
2985		;
2986		add_internal_error(
2987		'Expected information of used identifiers in exists information',Parameters:Infos),
2988		bsyntaxtree:find_identifier_uses(Condition, [], Used).
2989		% what if we call test_exists for a negated universal quantifier ??
2990
2991
2992
2993
2994		:- use_module(kernel_tools,[ground_state/1]).
2995		/* the following causes performance problems with examples/B/Mathematical/GraphIso/CheckGraphIsomorphism
2996		and with lausanne.mch in SMT mode */
2997		b_not_test_exists(Parameters,Condition,Infos,LocalState,State,_,WF) :-
2998		is_a_conjunct(Condition,LHS,RHS),
2999		preferences:preference(use_smt_mode,SMT),
3000		(SMT=true -> true
3001		; is_for_all_set_membership_predicate(LHS,Parameters,_,_,_)
3002		-> true % optimised processing is available in forall; important for test 1753
3003		),
3004		(\+ ground_state(LocalState) ; \+ ground_state(State)),
3005		% TO DO: check if any of the variables in Condition are not ground
3006		% TO DO: check if used_ids exist in Infos ? memberchk(used_ids(_),Infos),
3007		!,
3008		%print(translating_not_exists_into_forall),nl,print(' '),print_bexpr(LHS),nl, print('=> '),print_bexpr(RHS),nl,
3009		(SMT=true,
3010		is_for_all_set_membership_predicate(RHS,Parameters,_Set,_Pattern,_ParameterValues),
3011		\+ is_for_all_set_membership_predicate(LHS,Parameters,_,_,_)
3012		-> LLHS=RHS, RRHS=LHS % swap LHS and RHS; TO DO: search for membership predicate inside LHS,RHS !!
3013		; LLHS=LHS, RRHS=RHS
3014		),
3015		safe_create_texpr(negation(RRHS),pred,NegRHS),
3016		b_for_all(Parameters,Infos,LLHS,NegRHS,LocalState,State,WF).
3017		b_not_test_exists(Parameters,Condition,Infos,[],[],no_compile,WF) :- !,
3018		% already compiled in is_empty_closure_wf
3019		ground_bexpr_check(Condition,Ground),
3020		b_not_test_exists_aux(Ground,Parameters,Condition, Infos, WF).
3021		b_not_test_exists(Parameters,Condition,Infos,LocalState,State,_,WF) :-
3022		% compile to remove dependency on unused parts of State+LocalState; will make it delay less below
3023		def_get_texpr_ids(Parameters,ParaIDs),
3024		%% print(b_not_test_exists(ParaIDs)),nl, print(state(LocalState,State)),nl, %%
3025	?	b_compiler:b_compile(Condition,ParaIDs,LocalState,State,CompiledCond,WF),
3026		(is_truth(CompiledCond) -> fail
3027		; is_falsity(CompiledCond) -> true
3028		% TO DO: we could detect equalities that will always succeed (but be careful for WD issues)
3029		; ground_bexpr_check(CompiledCond,Ground),
3030		b_not_test_exists_aux(Ground,Parameters,CompiledCond, Infos, WF)
3031		).
3032
3033		:- block b_not_test_exists_aux(-,?,?,?,?).
3034		b_not_test_exists_aux(_,Parameters,CompiledCond,Infos,WF) :-
3035		% getting an idle waitflag considerably slows down test 1739; see also ClearSy/2019_Aug/call_residue/rule_erreur.mch
3036		% slow down no longer the case with the new waitflag implementation
3037		kernel_waitflags:get_idle_wait_flag(b_not_test_exists_aux(Parameters),WF,LWF),
3038		% allow pending co-routines to complete
3039		b_not_test_exists_aux2(LWF,Parameters,CompiledCond,Infos,WF).
3040		:- block b_not_test_exists_aux2(-,?,?,?,?).
3041		b_not_test_exists_aux2(_,Parameters,CompiledCond,Infos,WF) :-
3042		% no need to create inner waitflag: we enumerate fully below: create_inner_wait_flags(WF,b_not_test_exists(Parameters),LocalWF),
3043		%init_wait_flags(LocalWF,[expansion_context(b_not_not_test_exists,Parameters)]),
3044		init_quantifier_wait_flag(WF,not(exists),Parameters,ParaResult,Infos,LocalWF),
3045		not_with_enum_warning(
3046		b_interpreter:b_not_not_test_exists_aux(Parameters,ParaResult,CompiledCond,LocalWF),
3047		LocalWF, CompiledCond, % was not_exists(Parameters), the not_exists quantifier call is on call_stack now
3048		CompiledCond),
3049		copy_wfe_from_inner_if_necessary(LocalWF,WF). % for the case that the negated call has found abort errors and WFE was not grounded
3050		b_not_not_test_exists_aux(Parameters,ParaResult,CompiledCond,LocalWF) :-
3051	?	b_interpreter:set_up_typed_localstate(Parameters,ParaResult,TypedVals,[],NewLocalState,negated),
3052		% delay generation of WD error messages until outer WFE flag set
3053	?	b_interpreter:b_test_boolean_expression(CompiledCond,NewLocalState,[],LocalWF), % check Condition
3054		b_tighter_enumerate_values_in_ctxt(TypedVals,CompiledCond,LocalWF),
3055	?	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
3056		% pending co-routines will be discarded by negation !
3057
3058
3059		/* --------------------------------- */
3060
3061		value_type(_X). % only used in post_conditions (assert_post)
3062		/*
3063		value_type(X) :- nonvar(X),
3064		(X = value(_) ; X = global_set(_) ;
3065		X = global_constant(_) ; X = term(_)).*/
3066
3067
3068		% look up identifiers in store, if the identifier
3069		% is not in the store, assume it's a constant and ignore it
3070		% used for determining wait variables for existential quantifier
3071		% TO DO: better deal with CSE @identifiers ?
3072		lookup_values_if_vars([],_,_,[]).
3073		lookup_values_if_vars([Id|IRest],LocalStore,Store,Values) :-
3074		( lookup_value(Id,LocalStore,Store,Val)
3075		-> (force_evaluation_of_lazy_value(Id,Val,RealVal)
3076		-> Values = [RealVal|VRest]
3077		; Values = [Val|VRest])
3078		; Values = VRest),
3079		lookup_values_if_vars(IRest,LocalStore,Store,VRest).
3080
3081		force_evaluation_of_lazy_value(Id,Value,RealVal) :- nonvar(Value), Value=(Trigger,RealVal),
3082		var(Trigger),
3083		get_preference(use_common_subexpression_elimination,true),
3084		is_lazy_let_identifier(Id),
3085		!,
3086		Trigger=pred_true. % force evaluation, as the exists will otherwise delay/flounder
3087		% Warning: this means that outer lazy_let_expressions inside an exists should be well-defined (WD)
3088
3089
3090		/* will not generate error messages; used for CSP||B when we don't know if something is a B variable or not */
3091		/* TO DO: add peel_prefix for global_sets and constants ?? */
3092		try_lookup_value_in_store_and_global_sets(Id,State,Val) :-
3093		(lookup_value(Id,State,RVal) -> RVal=Val
3094		; b_global_sets:lookup_global_constant(Id,VGC) -> Val = VGC
3095		; b_global_set_or_free_type(Id,_AnyType,Value) -> Val=Value /* global set evaluates to itself */
3096		).
3097
3098
3099		lookup_value_in_store_and_global_sets_wf(Id,Type,LocalState,State,Val,Span,WF) :-
3100		(lookup_value_with_span_wf(Id,LocalState,State,RVal,Span,WF)
3101		-> RVal=Val
3102		; lookup_value_in_global_sets_wf(Id,Type,Val,LocalState,State,Span,WF)
3103		).
3104
3105		lookup_value_in_global_sets_wf(Id,Type,Val,LocalState,State,Span,WF) :-
3106		(b_global_sets:lookup_global_constant(Id,VGC)
3107		-> Val=VGC
3108	?	; (b_global_set_or_free_type(Id,Type,Value)
3109		-> Val = Value /* global set evaluates to itself */
3110		; ((member(bind(Id,_),LocalState) ; member(bind(Id,_),State))
3111		-> Msg1 = 'Cannot determine value for identifier '
3112		; Msg1 = 'Cannot find identifier '
3113		),
3114		append(LocalState,State,LSS),
3115		translate:translate_bstate_limited(LSS,StateInfo),
3116		ajoin([Msg1,Id,':'],Msg),
3117		add_error_wf(identifier_not_found,Msg,StateInfo,Span,WF),
3118		fail % Val = term(Id) /* Val=fail */
3119		)
3120		).
3121
3122		:- use_module(probsrc(kernel_freetypes),[registered_freetype/2, registered_freetype_case_value/3]).
3123	?	b_global_set_or_free_type(Id,_,global_set(Id)) :- b_global_set(Id).
3124		b_global_set_or_free_type(Id,_,freetype(Id)) :- registered_freetype(Id,_).
3125		b_global_set_or_free_type(Id,Type,Value) :-
3126		registered_freetype_case_value(Id,Type,Value). % to instantiate the type parameters we also need the TypeId
3127		% TODO: we could also register Event-B destructors and look them up here
3128
3129		/* -----------------------------*/
3130		/* b_compute_expressions */
3131		/* -----------------------------*/
3132
3133		b_compute_expressions([], _, _, [],_WF).
3134		b_compute_expressions([EXPRsHd|EXPRsTl],LocalState,InState,[ValHd|ValTl],WF) :-
3135	?	b_compute_expression(EXPRsHd,LocalState,InState,ValHd,WF),
3136	?	b_compute_expressions(EXPRsTl,LocalState,InState,ValTl,WF).
3137
3138		% a variation of above that delays computing the expressions until Waitflag 1/2 is set
3139		b_compute_assign_expressions_when(EXPRsTl,LocalState,InState,ValTl,WF,OR) :-
3140		get_assign_expr_priority_wf(OR,WF,LWF),
3141	?	b_compute_expressions_when2(EXPRsTl,LocalState,InState,ValTl,WF,LWF).
3142		b_compute_expressions_when2([], _, _, [],_WF,_).
3143		b_compute_expressions_when2([EXPRsHd|EXPRsTl],LocalState,InState,[ValHd|ValTl],WF,LWF) :-
3144	?	b_compute_expression_when2(EXPRsHd,LocalState,InState,ValHd,WF,LWF),
3145		b_compute_expressions_when2(EXPRsTl,LocalState,InState,ValTl,WF,LWF).
3146
3147		% TO DO: add step number in OR
3148		get_assign_expr_priority_wf(output_required,_WF,LWF) :- !,
3149		% the Output of the statement is required; do not delay computing it
3150		LWF=0. % this would delay computation until WF0 is set: get_wait_flag0(WF,LWF); cf. initialisation for test 2104
3151		get_assign_expr_priority_wf(_,WF,LWF) :-
3152		% the Output is not directly required; compute it later (when we are sure that the statement actually succeeds)
3153		(preferences:preference(use_smt_mode,true)
3154		-> Prio = 2.0 % SMT Mode: we are probably doing CBC checking, we may have set up constraints on ValTl
3155		; 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
3156		get_wait_flag(Prio,get_assign_expr_priority_wf,WF,LWF).
3157
3158		:- block b_compute_expression_when2(?,?,?,?,?,-).
3159		b_compute_expression_when2(eval_must_not_fail(ErrMsg,EXPRsHd),LocalState,InState,Res,WF,_) :- !,
3160		% catch failure; in case the interpreter fails to catch wd-error itself (e.g., try_find_abort is false)
3161		if(b_compute_expression(EXPRsHd,LocalState,InState,ValHd,WF),equal_object_wf(ValHd,Res,WF),
3162		(translate:translate_bexpression_with_limit(EXPRsHd,TS),
3163		add_wd_error_span(ErrMsg,TS,span_predicate(EXPRsHd,LocalState,InState),WF))).
3164		b_compute_expression_when2(EXPRsHd,LocalState,InState,ValHd,WF,_) :-
3165		copy_wf_start(WF,b_compute_expression_when2,CWF), % not sure this is useful for expressions:
3166	?	b_compute_expression(EXPRsHd,LocalState,InState,ValHd,CWF),
3167	?	copy_wf_finish(WF,CWF).
3168
3169
3170		/* -----------------------------*/
3171		/* b_execute_statement */
3172		/* -----------------------------*/
3173		/* b_execute_statement(XMLStatements:input, StateofLocalVariables:input,
3174		StateOfGlobalVariables:input,
3175		ListOfUpdateBindingsForGlobalVariablesAndResultVariables:output) */
3176
3177		:- assert_pre(b_interpreter:b_execute_statement(Stmt,LS,IS,_OS,_WF,_Path,_OR),
3178		(bsyntaxtree:check_if_typed_substitution(Stmt),type_check(LS,store),type_check(IS,store) )).
3179		:- assert_post(b_interpreter:b_execute_statement(_Stmt,_LS,_IS,OS,_WF,_Path,_OR),
3180		(type_check(OS,store))).
3181
3182		b_execute_inner_statement(Body,LocalState,InState,OutState,WF,Path,output_required) :-
3183		get_texpr_expr(Body,BE),
3184		BE \= while(_COND,_STMT,_INV,_VARIANT), % also other non-det substitutions ??
3185		BE \= select(_),
3186		BE \= select(_,_),
3187		BE \= if(_), % case(_,_,_) statements are now translated to if-then-else in ast_cleanup
3188		!,
3189		get_wait_flag0(WF,WF0),
3190		block_execute_statement(WF0,Body,LocalState,InState,OutState,WF,Path).
3191		b_execute_inner_statement(Body,LocalState,InState,OutState,WF,Path,OR) :-
3192		get_wait_flag(2,inner_stmt,WF,LWF), % was 2.0
3193		clone_wait_flags_from1(WF,GroundUponFinish,InnerWF), % copy everything but WF0
3194		b_execute_inner_statement(Body,LocalState,InState,OutState,GroundUponFinish,InnerWF,Path,LWF,OR).
3195
3196		:- block block_execute_statement(-, ?,?,?, ?,?,?).
3197		block_execute_statement(_,Body,LocalState,InState,OutState,WF,Path) :-
3198	?	b_execute_statement(Body,LocalState,InState,OutState,WF,Path,output_required).
3199
3200		:- block b_execute_inner_statement(?,?,?,?,?,?,?,-,?).
3201		b_execute_inner_statement(Body,LocalState,InState,OutState,GUF,InnerWF,Path,_,OR) :-
3202	?	b_execute_statement(Body,LocalState,InState,OutState,InnerWF,Path,OR),
3203		(GUF=ground_upon_finish -> ground_wait_flags(InnerWF) ; ground_wait_flag0(InnerWF)).
3204
3205		:- use_module(source_profiler,[opt_add_source_location_hits/2]).
3206		:- use_module(b_operation_guards,[get_substitution_enabling_condition/4]).
3207
3208
3209		b_execute_statement_nowf(Subst,LS,S,OutS,Ctxt) :-
3210		init_wait_flags_with_call_stack(WF,[prob_command_context(Ctxt,unknown)]),
3211		b_interpreter:b_execute_statement(Subst,LS,S,OutS,WF,_Path),
3212		ground_wait_flags(WF).
3213
3214		b_execute_statement(Stmt, LS, S, OS, WF,Path) :-
3215	?	b_execute_statement(Stmt, LS, S, OS, WF,Path,output_not_required).
3216		b_execute_statement(b(Stmt,_,Infos), LS, S, OS, WF,Path,OR) :- !,
3217	?	b_execute_statement2(Stmt, Infos, LS, S, OS, WF,Path,OR).
3218		b_execute_statement(Stmt, LS, S, OS, WF,Path,OR) :-
3219		add_internal_error('Statement not properly wrapped: ',b_execute_statement(Stmt, LS, S, OS, WF,Path,OR)),
3220		b_execute_statement2(Stmt, [], LS, S, OS, WF,Path,OR).
3221
3222		% blocks should be removed by type-checker
3223		b_execute_statement2(block(Stmt),_,LS,IS,OS,WF,Path,OR) :- !,
3224		b_execute_statement(Stmt,LS,IS,OS,WF,Path,OR). %% NOT COVERED
3225		b_execute_statement2(assign(LHS,Exprs),Info,LocalState,InState,OutState,WF,assign(LHS,VALs),OR) :- !,
3226		/* Var1, ..., VarN := Expr1, ..., ExprN */
3227		/* also: Var1, fun1(arg), ... := Expr1, Expr2, ... */
3228		opt_add_source_location_hits(Info,1),
3229	?	b_compute_assign_expressions_when(Exprs,LocalState,InState,VALs,WF,OR),% VALs - a list of computed values
3230	?	b_assign_values_or_functions(LHS,VALs,LocalState,InState,OutState,WF,OR).
3231		b_execute_statement2(assign_single_id(IDE,Expr),Info,LocalState,InState,OutState,WF,assign_single_id(ID,Value),_OR) :-
3232		get_texpr_id(IDE,ID),!,
3233		opt_add_source_location_hits(Info,1),
3234	?	b_compute_expression(Expr,LocalState,InState,Value,WF), % b_compute_assign_expressions_when
3235		%b_compute_assign_expressions_when([Expr],LocalState,InState,[Value],WF),
3236		OutState=[bind(ID,Value)].
3237		b_execute_statement2(choice(ChoiceList),_,LocalState,InState,OutState,WF,Path,OR) :- !,
3238		/* CHOICE LHS OR RHS OR ... END */
3239		get_wait_flag(2,choice,WF,WFC), % % was 2.0, maybe use length of ChoiceList as Priority ??
3240		b_execute_choice(ChoiceList,LocalState,InState,OutState,WF,Path,WFC,OR).
3241		b_execute_statement2(becomes_element_of(LHS,RHS), /* LHS :: RHS */
3242		Info,LocalState,InState,OutState,WF,Path,_OR) :- !,
3243		% LHS must be of the form Var1,..,Vark where all variables are disjoint
3244		opt_add_source_location_hits(Info,1),
3245		b_execute_becomes_element_of(LHS,RHS,LocalState,InState,OutState,WF,Path).
3246		b_execute_statement2(becomes_such(Vars,Condition),Info,LocalState,InState,OutState,WF,Path,OR) :- !,
3247		/* Vars : (Condition) */
3248		opt_add_source_location_hits(Info,1),
3249		(OR=output_required, get_preference(expand_becomes_such_into_set,true) % see test 1770
3250		-> % compute all solutions of the Condition predicate and then choose amongst them;
3251		% possibly good for complex preds, ensures we solve local constraints in isolation in context of sequence(.)
3252		% runs into time_out for test 2093; TODO: detect special patterns like partial_function, ...
3253		insert_before_substitution_variables(Vars,LocalState,InState,LocalState,TempLocalState),
3254		add_debug_message(b_interpreter,'Expanding become_such predicate into set: ',Condition,Condition),
3255		b_compute_comprehension_set(Vars,Condition,Info,TempLocalState,InState,CResult,WF),
3256		RHS = b(value(CResult),any,[was(becomes_such)]),
3257		b_execute_statement2(becomes_element_of(Vars,RHS), Info,LocalState,InState,OutState,WF,Path,OR)
3258		; % create Vars in State and assert that Condition is true; probably good for cbc checking
3259	?	b_execute_becomes_such(Vars,Condition,Info,LocalState,InState,OutState,_,Path,WF)
3260		).
3261		b_execute_statement2(sequence(Seq), /* LHS ; RHS */
3262		_,LocalState,InState,OutUpdates,WF,Path,OR) :- !, %pe_print(sequence(Seq,InState)),
3263	?	b_execute_sequence(Seq,LocalState,InState,OutUpdates,WF,Path,OR).
3264		b_execute_statement2(precondition(PreCond,Body),_,LocalState,InState,OutState,WF,Path,OR) :- !,
3265		%print('*** Non-outermost PRE construct'),nl,
3266		Path=pre(PreRes,IPath),
3267		b_try_check_boolean_expression(PreCond,LocalState,InState,WF,PreRes),
3268		%used to be: ground_det_wait_flag(WF),
3269		check_precondition_result(PreRes,PreCond,LocalState,InState,WF),
3270	?	(PreRes == pred_true -> b_execute_statement(Body,LocalState,InState,OutState,WF,IPath,OR)
3271		; PreRes == pred_false -> IPath = not_executed
3272		; b_execute_inner_statement(Body,LocalState,InState,OutState,WF,IPath,OR) % with extra waitflag
3273		).
3274		b_execute_statement2(assertion(PreCond,Body),_,LocalState,InState,OutState,WF,Path,OR) :- !,
3275	?	b_execute_assertion(PreCond,Body,LocalState,InState,OutState,WF,Path,OR).
3276		b_execute_statement2(witness_then(PreCond,Body),_,LocalState,InState,OutState,WF,witness(Path),OR) :- !,
3277		b_test_boolean_expression(PreCond,LocalState,InState,WF),
3278		b_execute_inner_statement(Body,LocalState,InState,OutState,WF,Path,OR).
3279		b_execute_statement2(select(Whens),_, LocalState, InState, OutState,WF,select(Nr,Path),OR) :- !,
3280		get_texpr_expr(TExpr,select_when(PreCond, Body)), % info field not used for select_when
3281	?	optimized_nth1(Nr, Whens, TExpr), % THIS IS A CHOICE POINT if length(Whens)>1 ! <-------- TO DO guard
3282	?	b_test_boolean_expression(PreCond,LocalState,InState,WF),
3283		%used to call: ground_det_wait_flag(WF), now execute inner statement delays
3284		b_execute_inner_statement(Body,LocalState,InState,OutState,WF,Path,OR).
3285		b_execute_statement2(select(Whens,Else), Infos, LocalState, InState, OutState,WF,Path,OR) :- !,
3286		(
3287	?	b_execute_statement2(select(Whens), Infos, LocalState, InState, OutState,WF,Path,OR)
3288		; % THIS IS A CHOICE POINT ! <-------- TO DO guard
3289		findall(PC,
3290		(member(SW,Whens),get_texpr_expr(SW,select_when(PC,_))), AllPreconds),
3291		b_not_test_list_of_boolean_expression(AllPreconds,LocalState,InState,WF),
3292		Path = select(else,IPath),
3293		b_execute_inner_statement(Else,LocalState,InState,OutState,WF,IPath,OR)
3294		).
3295		b_execute_statement2(var(Parameters,Body), /* VAR _ IN _ substitution */
3296		_,LocalState,InState,NewOutState,WF,var(Names,Path),OR) :- !,
3297		/* introduces a new variable that can be assigned to */
3298		split_names_and_types(Parameters,Names,_),
3299		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 !!
3300		% otherwise we may think there are two updates, e.g., in WHILE loop; see Rule_DB_SIGAREA_0030 from test 1303
3301		set_up_undefined_localstate(Parameters,InState1,NewInState),
3302		delete_variables_from_state(Names,LocalState,NewLocalState),
3303		%check_valid_store(InState,var_in_state), check_valid_store(LocalState,var_local_state),
3304	?	b_execute_statement(Body,NewLocalState,NewInState,OutState,WF,Path,OR),
3305		% check_valid_store(OutState,var_out_state),
3306		filter_results(Parameters,OutState,NewOutState,WF)
3307		.
3308		/* it can be ok not to assign to a local variable */
3309
3310		%TODO(DP, 5.8.2008):
3311		b_execute_statement2(let(Parameters,Defs,Body), /* LET _ BE _ IN _ */
3312		_,LocalState,InState,OutState,WF,let(Path),OR) :- !,
3313	?	set_up_typed_localstate(Parameters,LocalState,NewLocalState),
3314		b_execute_let_definitions(Defs,NewLocalState,InState,WF),
3315	?	b_execute_statement(Body,NewLocalState,InState,OutState,WF,Path,OR).
3316		b_execute_statement2(lazy_let_subst(Id,IdExpr,Body),_,LocalState,InState,OutState,WF,lazy_let(Path),OR) :-
3317		!,
3318		add_lazy_let_id_and_expression(Id,IdExpr,LocalState,InState,NewLocalState,WF),
3319		b_execute_statement(Body,NewLocalState,InState,OutState,WF,Path,OR).
3320		b_execute_statement2(any(Parameters,PreCond,Body), /* ANY _ WHERE */
3321		Info,LocalState,InState,OutState,WF0,any(Bindings,Path),OR) :- !, %statistics(runtime,_),
3322		%print('ANY: '), print_bexpr(PreCond),nl, %%
3323	?	set_up_typed_localstate(Parameters,FreshVars,TypedVals,LocalState,NewLocalState,positive),
3324		create_any_bindings(Parameters,FreshVars,Bindings),
3325		push_wait_flag_call_stack_info(WF0,quantifier_call('ANY',Parameters,FreshVars,Info),WF),
3326	?	b_test_inner_boolean_expression(PreCond,NewLocalState,InState,WF), /* check WHERE */
3327		%%observe_state(TypedVals,WF,0), b_tracetest_boolean_expression(PreCond,NewLocalState,InState,WF,one), %% comment in for debugging
3328		b_tighter_enumerate_all_values(TypedVals,WF), % moved enumeration after test; in case WF already instantiated
3329		%TODO: check if we can use b_tighter_enumerate_values_in_ctxt
3330	?	b_execute_statement(Body,NewLocalState,InState,OutState,WF,Path,OR). /* should we use b_execute_inner_statement/LWF here ?? */
3331		b_execute_statement2(skip, /* SKIP */
3332		Info,_LocalState,_InState,OutState,_WF,skip,_OR) :- !,
3333		opt_add_source_location_hits(Info,1),
3334		OutState = [].
3335		b_execute_statement2(parallel(Statements), /* LHS || RHS */ %@@@
3336		_,LocalState,InState,OutState,WF,parallel(Paths),OR) :- !,
3337	?	b_execute_statements_in_parallel(Statements,LocalState,InState,OutState,WF,Paths,OR).
3338		b_execute_statement2(init_statement(Stmt),_,LocalState,InState,OutState,WF,Path,OR) :- !,
3339		/* Like block: but
3340		writes error messages if statement fails */ %@@@
3341		(get_preference(provide_trace_information,true)
3342		-> nl,print(' =INIT=> '),translate:print_subst(Stmt),nl, flush_output(user_output),
3343		statistics(walltime,[Tot1,_])
3344		; true),
3345	?	if(b_execute_initialisation_statement(Stmt,LocalState,InState,OutState,WF,Path,OR),
3346		(
3347		(get_preference(provide_trace_information,true)
3348		-> statistics(walltime,[Tot2,_]), Tot is Tot2-Tot1,
3349		format(' [=OK= ~w ms]~n',[Tot]), flush_output(user_output)
3350		; true)
3351		),
3352		( translate:translate_substitution(Stmt,TStmtStr),
3353		(bmachine:b_machine_temp_predicate(_TempPred)
3354		-> Msg = 'INITIALISATION statement cannot be executed with extra predicate: ',
3355		add_error_wf(initialisation_fails,Msg,TStmtStr,Stmt,WF)
3356		% do not add as state error; user requested transition
3357		; Msg = 'INITIALISATION statement fails: ',
3358		(get_substitution_enabling_condition(Stmt,SpanPred,_BSVars,_IsPreciseV)
3359		-> %insert_custom_predicate_into_guard(EnablingCondition,TempPred,SpanPred),
3360		ErrPos = span_predicate(SpanPred,LocalState,InState) % for visualising by user
3361		% Note: user can also visualise by chooise execute by predicate (in TK)
3362		; ErrPos = Stmt
3363		),
3364		% add as state error so that we can visualise span predicate
3365		add_state_error_wf(initialisation_fails,Msg,TStmtStr,ErrPos,WF) % cf test 1736 and 278
3366		%add_error_wf(initialisation_fails,Msg,TStmtStr,ErrPos,WF)
3367		),
3368		fail
3369		)
3370		).
3371		b_execute_statement2(if(IfList),_,LocalState,InState,OutState,WF,Path,OR) :- !,
3372		LWF='$GENERATE_ON_DEMAND',
3373	?	b_execute_else_list(IfList,LocalState,InState,OutState,WF,1,Path,LWF,OR).
3374		b_execute_statement2(operation_call(Operation,Results,Parameters),Info,LocalState,InState,OutState,WF,
3375		operation_call(OperationName,Results,ParamValues,ResultValues,InnerPath),OR) :- !,
3376		def_get_texpr_id(Operation,op(OperationName)),
3377	?	b_execute_operation_with_parameters(OperationName,LocalState,InState,Results,
3378		Parameters,OpOutState,ParamValues,ResultValues,InnerPath,Info,WF,OR),
3379		opt_add_source_location_hits(Info,1),
3380		split_names_and_types(Results,ResultingIDs,_),
3381		store_values(ResultingIDs, ResultValues, ResultsOutState),
3382		combine_updates(ResultsOutState,OpOutState,OutState).
3383
3384		b_execute_statement2(while(COND,STMT,INV,VARIANT),
3385		Info,LocalState,InState,OutState,WF0,while(VarVal,BodyPath),_OR) :- !,
3386		%hit_profiler:add_profile_hit(while(COND,WF),2),
3387		% we may go around the loop many times: avoid carrying around unused variables
3388		get_while_reads_write_info_and_filter_state(Info,LocalState,InState,LS,IS,ModVars),
3389		push_wait_flag_call_stack_info(WF0,b_operator_call('WHILE',[VarVal],Info),WF), % TODO: provide subst. call stack entry
3390		%print_message(execute_while(LocalState,InState)),
3391		b_compiler:b_optimize(INV,ModVars,LS,IS,CINV,WF),
3392		b_compiler:b_optimize(COND,ModVars,LS,IS,CCOND,WF),
3393		b_compiler:b_optimize(VARIANT,ModVars,LS,IS,CVARIANT,WF),
3394		%,b_compiler:b_compile(STMT,ModVars,LS,IS,CSTMT,WF)
3395		% TO DO: maybe exclude in one go; use ordered approach ?
3396		%exclude(unused_variable(ModVars),LS,LS2), % only keep modified vars; all other compiled
3397		%exclude(unused_variable(ModVars),IS,IS2), % only keep modified vars; all other compiled
3398		b_compute_expression(CVARIANT,LS,IS,VarVal,WF),
3399		b_execute_while(CCOND,STMT,CINV,CVARIANT,ModVars,VarVal,LS,IS,OutState,WF,BodyPath).
3400		b_execute_statement2(external_subst_call(FunName,Args),Info,LocalState,State,OutState,WF,external_subst(FunName),_OR) :-
3401		!, b_compute_expressions(Args, LocalState,State, EvaluatedArgs, WF),
3402		push_wait_flag_call_stack_info(WF,external_call(FunName,EvaluatedArgs,Info),WF2),
3403		call_external_substitution(FunName,EvaluatedArgs,State,OutState,Info,WF2).
3404		b_execute_statement2(E,I,LS,S,O,WF,Path,OR) :-
3405		add_internal_error('Uncovered statement: ',b_execute_statement2(E,I,LS,S,O,WF,Path,OR)),
3406		print_functor(E),nl,fail.
3407
3408		% -------------------
3409
3410		b_execute_becomes_element_of(LHS,RHS,LocalState,InState,OutState,WF,becomes_element_of(LHS,SingleValue)) :-
3411		b_compute_expression(RHS,LocalState,InState,ValueSet,WF),
3412		(get_preference(warn_about_failing_assignments,false)
3413		-> b_execute_becomes_element_of_aux(LHS,SingleValue,ValueSet,OutState,WF)
3414		; if(b_execute_becomes_element_of_aux(LHS,SingleValue,ValueSet,OutState,WF),
3415		true,
3416		(add_feasibility_error(b(not_equal(RHS,b(empty_set,any,[])),pred,[]),
3417		'Assignment by set (becomes_element_of) fails:', LocalState,InState,WF),
3418		SingleValue = term(undefined),
3419		OutState = [] % pretend no assignment occurred (skip)
3420		))
3421		).
3422		b_execute_becomes_element_of_aux(LHS,SingleValue,ValueSet,OutState,WF) :-
3423		convert_pairs_into_list(LHS,SingleValue,ValList),
3424		set_up_typed_localstate(LHS,ValList,TypedVals,[],OutState,positive),
3425		check_element_of_wf(SingleValue,ValueSet,WF),
3426		ground_det_wait_flag(WF), %% TODO: remove this
3427		b_tighter_enumerate_all_values(TypedVals,WF).
3428
3429		:- use_module(b_interpreter_components,[construct_optimized_exists/3]).
3430		b_execute_becomes_such(Vars,Condition,Info,LocalState,InState,OutState,Values,becomes_such(Ids,Values),WF) :- !,
3431		% create the LHS variables in the local state
3432	?	set_up_typed_localstate(Vars,Values,TypedVals,LocalState,TempLocalState1,positive),
3433		get_texpr_ids(Vars,Ids),
3434		% there might be some variables of the form x$0 to access the
3435		% values before the substitution. We put them into the local state
3436		insert_before_substitution_variables(Vars,LocalState,InState,TempLocalState1,TempLocalState),
3437		push_wait_flag_call_stack_info(WF,quantifier_call(':(_)',Vars,Values,Info),WF1),
3438		(get_preference(warn_about_failing_assignments,false)
3439		-> % store those values also into the outgoing state as bind/2 pairs
3440		store_values(Ids,Values,OutState),
3441	?	b_test_inner_boolean_expression(Condition,TempLocalState,InState,WF1),
3442		b_tighter_enumerate_values_in_ctxt(TypedVals,Condition,WF1)
3443		; if((store_values(Ids,Values,OutState),
3444		b_test_inner_boolean_expression(Condition,TempLocalState,InState,WF1),
3445		b_tighter_enumerate_values_in_ctxt(TypedVals,Condition,WF1)),
3446		true, % Note: the predicate could still fail later when WF1 is instantiated !
3447		(construct_optimized_exists(Vars,Condition,EC,false),
3448		add_feasibility_error(EC,'Assignment by predicate (becomes_such) fails:',TempLocalState,InState,WF1),
3449		OutState = [] % pretend no assignment occurred (skip)
3450		)
3451		)
3452		).
3453		% moved enumeration after test, to avoid overhead in case Condition is deterministic
3454		% (see e.g. WhileAssignTupleChoose_v2)
3455
3456		add_feasibility_error(Condition,Msg,LS,S,WF) :-
3457		translate_bexpression(Condition,CS),
3458		add_abort_error_span(feasibility_error, Msg, CS,span_predicate(Condition,LS,S),WF).
3459
3460		b_execute_sequence([],_LocalState,_InState,[],_WF,[],_OR).
3461		b_execute_sequence([First|Rest],LocalState,InState,OutUpdates,WF,Path,OR) :-
3462		(Rest == []
3463	?	-> b_execute_statement(First,LocalState,InState,OutUpdates,WF,Path,OR)
3464		; Path = sequence(Path1,RestPath),
3465	?	b_execute_statement(First,LocalState,InState,LHSUpdates,WF,Path1,output_required),
3466	?	ground_det_wait_flag(WF), % maybe better to delay next execute_statement ? TODO
3467		store_intermediate_updates_wf(InState,LHSUpdates,IntermediateState,First,WF),
3468		% TO DO: statically determine what the Rest can modify and copy over LHSUpdates not modified by Rest into OutUpdates
3469	?	b_execute_statement_list_when_state_set(Rest,LocalState,IntermediateState,
3470		LHSUpdates,OutUpdates,WF,RestPath,OR)
3471		).
3472
3473
3474		:- block check_precondition_result(-,?,?,?,?).
3475		check_precondition_result(pred_true,_,_,_,_).
3476		check_precondition_result(pred_false,PreCond,LS,S,WF) :-
3477		translate_bexpression(PreCond,PreString),
3478		add_abort_error_span(precondition_error,'Precondition violated: ',PreString,span_predicate(PreCond,LS,S),WF).
3479
3480		create_any_bindings([],[],[]).
3481		create_any_bindings([Param|Prest],[Value|Vrest],[bind(Id,Value)|Brest]) :-
3482		get_texpr_id(Param,Id),
3483		create_any_bindings(Prest,Vrest,Brest).
3484
3485		% insert the values of variables before the substitution under an
3486		% alternative name. The alternative name is given as an optional extra
3487		% information in the variable (see type-checking of becomes_such for
3488		% details). Usually (i.e. always) the alternative name is x$0 for the variable x.
3489		insert_before_substitution_variables([],_LocalState,_InState,State,State).
3490		insert_before_substitution_variables([Var|VRest],LocalState,InState,StateA,ResultStateB) :-
3491		get_texpr_info(Var,Infos),
3492	?	( member(before_substitution(_,Alternative),Infos) ->
3493		def_get_texpr_id(Var,Id),
3494		lookup_value_for_existing_id(Id,LocalState,InState,Value),
3495		store_value(Alternative,Value,StateA,StateC)
3496		;
3497		StateA = StateC),
3498		insert_before_substitution_variables(VRest,LocalState,InState,StateC,ResultStateB).
3499
3500
3501
3502		% treat the bool(.) operator
3503		b_convert_bool(Pred,LocalState,State,WF,PredRes) :-
3504		get_wait_flag0(WF,WF0), % first give a chance for PredRes to be instantiated
3505		b_convert_bool_wf0(Pred,LocalState,State,WF,PredRes,WF0).
3506
3507		:- block b_convert_bool_wf0(?,?,?,?,-,-).
3508		b_convert_bool_wf0(Pred,LocalState,State,WF,PredRes,_) :- PredRes==pred_true,!,
3509		%% print('bool(.)=TRUE '), translate:print_bexpr(Pred),nl, %%
3510		b_test_inner_boolean_expression(Pred,LocalState,State,WF).
3511		b_convert_bool_wf0(Pred,LocalState,State,WF,PredRes,_) :- PredRes==pred_false,!,
3512		%% print('bool(.)=FALSE '), translate:print_bexpr(Pred),nl, %%
3513		b_not_test_inner_boolean_expression(Pred,LocalState,State,WF).
3514		b_convert_bool_wf0(Pred,LocalState,State,WF,PredRes,_) :-
3515		%% print('bool(.) check : '), translate:print_bexpr(Pred),nl, % obsv(LocalState),
3516	?	b_try_check_boolean_expression_wf(Pred,LocalState,State,WF,PredRes ).
3517		%% print('finished bool(.) check : '), translate:print_bexpr(Pred),nl,translate:print_bstate(LocalState),nl.
3518
3519		% Additional time limit +TO in ms, e.g., used for CDCL(T). +TORes is time_out if a timeout occurred.
3520		b_convert_bool_timeout(Pred,LocalState,State,WF,PredRes,TO,TORes) :-
3521		get_wait_flag0(WF,WF0),
3522		b_convert_bool_wf0_timeout(Pred,LocalState,State,WF,PredRes,WF0,TO,TORes).
3523
3524		:- block b_convert_bool_wf0_timeout(?,?,?,?,-,-,?,?).
3525		b_convert_bool_wf0_timeout(Pred,LocalState,State,WF,PredRes,_,TO,TORes) :-
3526		PredRes == pred_true,
3527		!,
3528		safe_time_out(b_test_inner_boolean_expression(Pred,LocalState,State,WF),
3529		TO,
3530		TORes).
3531		b_convert_bool_wf0_timeout(Pred,LocalState,State,WF,PredRes,_,TO,TORes) :-
3532		PredRes == pred_false,
3533		!,
3534		safe_time_out(b_not_test_inner_boolean_expression(Pred,LocalState,State,WF),
3535		TO,
3536		TORes).
3537		b_convert_bool_wf0_timeout(Pred,LocalState,State,WF,PredRes,_,TO,TORes) :-
3538		safe_time_out(b_try_check_boolean_expression_wf(Pred,LocalState,State,WF,PredRes ),
3539		TO,
3540		TORes).
3541
3542		%%obsv([]).
3543		%%obsv([bind(Var,Val) | T] ) :- when(ground(Val), format("~w = ~w~n",[Var,Val])), obsv(T).
3544
3545		% check boolean expression without enumeration predicate result (unless WFE is set)
3546		b_try_check_boolean_expression_no_enum_wf(Pred,LocalState,State,WF,PredRes) :-
3547		b_try_check_boolean_expression_lwf(Pred,LocalState,State,WF,'$NO_ENUMERATION',PredRes,_).
3548
3549		b_try_check_boolean_expression_wf(Pred,LocalState,State,WF,PredRes) :-
3550	?	b_try_check_boolean_expression_lwf(Pred,LocalState,State,WF,'$ENUMERATION',PredRes,'$GENERATE_ON_DEMAND' ).
3551		% try to do check_boolean expression; if not possible create choice point if LWF is grounded
3552		b_try_check_boolean_expression_lwf(Pred,LocalState,InState,WF,DoEnumeration,PredRes,LWF) :-
3553	?	b_compiler:b_optimize(Pred,[],LocalState,InState,CPRED,WF), % this increases chance that check can be applied+avoids multiple computations in two branches
3554		% still: some computations may not be pre-computed, e.g., union of closures, ..., see Rule_DB_PSR_0003_C
3555	?	b_try_check_boolean_expression_lwf_c(CPRED,LocalState,InState,WF,DoEnumeration,PredRes,LWF).
3556
3557		b_try_check_boolean_expression_lwf_c(b(truth,_,_),_LocalState,_InState,_WF,_,PredRes,_LWF) :- !,
3558		% typical case in e.g. IF-THEN-ELSE
3559		PredRes= pred_true.
3560		b_try_check_boolean_expression_lwf_c(Pred,LocalState,InState,WF,DoEnumeration,PredRes,LWF) :-
3561		copy_wf_start(WF,try_check,CWF),
3562	?	if(b_check_boolean_expression_with_enum(Pred,LocalState,InState,CWF,DoEnumeration,Res),
3563		% Note: we do not use a cut here ! usually b_check will not enumerate; but on rare occasions it can (apply function in inverse,...)
3564		(PredRes=Res,
3565	?	copy_wf_finish(WF,CWF)
3566		),
3567		b_try_check_failed(Pred,LocalState,InState,WF,DoEnumeration,PredRes,LWF)
3568		).
3569		b_try_check_failed(Pred,LocalState,InState,WF,DoEnumeration,PredRes,LWF) :-
3570		% print(choice_point(LWF)),nl, translate:print_bexpr(Pred),nl,
3571		perfmessagecall(choice_point,reification_of_check_predicate_failed,translate:print_bexpr(Pred),Pred),
3572		(LWF=='$GENERATE_ON_DEMAND' -> get_binary_choice_wait_flag('$GENERATE_ON_DEMAND',WF,WF1)
3573		; var(LWF),DoEnumeration=='$NO_ENUMERATION' -> get_enumeration_finished_wait_flag(WF,WF1) % nothing will enum LWF
3574		; WF1=LWF),
3575		b_try_check_boolean_expression_lwf_block(Pred,LocalState,InState,WF,PredRes,WF1).
3576
3577		% a version of b_check_boolean_expression which will enumerate its result as last resort
3578		% should we only do this in SMT mode : preferences:preference(use_smt_mode,true) ?
3579		b_check_boolean_expression_with_enum(Pred,LocalState,State,WF,DoEnumeration,Res) :-
3580	?	b_check_boolean_expression(Pred,LocalState,State,WF,Res),
3581		(nonvar(Res) -> true
3582		; DoEnumeration=='$NO_ENUMERATION' -> get_enumeration_finished_wait_flag(WF,EWF), enum_pred_result(Res,EWF,WF)
3583		; get_wait_flag0(WF,LWF0),
3584		enum_pred_result0(Res,LWF0,WF)).
3585
3586		% first set up with wait_flag0: easy to get, avoid putting unnecessary waitflags into store
3587		% relevant for DataValidationTest.mch with n>20000
3588		:- block enum_pred_result0(-,-,?).
3589		enum_pred_result0(Res,_,WF) :- var(Res),!,
3590		get_last_wait_flag(b_check_boolean_expression_with_enum,WF,LWF),
3591		enum_pred_result(Res,LWF,WF). % before doing infinite enumerations: better do case-distinction here
3592		enum_pred_result0(_,_,_).
3593
3594		:- block enum_pred_result(-,-,?).
3595		enum_pred_result(pred_true,_,_).
3596		enum_pred_result(pred_false,_,_).
3597
3598		:- block b_try_check_boolean_expression_lwf_block(?,?,?, ?,-,-).
3599		b_try_check_boolean_expression_lwf_block(Pred,LocalState,InState,WF,PREDRES,_) :-
3600		PREDRES \== pred_false,
3601		% print(' TRUE +++++> '), translate:print_bexpr(Pred),nl,
3602	?	b_test_inner_boolean_expression(Pred,LocalState,InState,WF),
3603		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
3604		b_try_check_boolean_expression_lwf_block(Pred,LocalState,InState,WF,PREDRES,_) :-
3605		PREDRES \== pred_true,
3606		% print(' FALSE +++++> '), translate:print_bexpr(Pred),nl,
3607		b_not_test_inner_boolean_expression(Pred,LocalState,InState,WF),
3608		PREDRES = pred_false.
3609
3610		% try to do check_boolean expression; if not possible create choice point *directly*
3611		b_try_check_boolean_expression(Pred,LocalState,InState,WF,PredRes) :-
3612		b_compiler:b_optimize(Pred,[],LocalState,InState,CPRED,WF), % this increases chance that check can be applied+avoids multiple computations in two branches
3613		b_try_check_boolean_expression_c(CPRED,LocalState,InState,WF,PredRes).
3614		b_try_check_boolean_expression_c(Pred,LocalState,InState,WF,PredRes) :-
3615		copy_wf_start(WF,try_check_c,CWF),
3616		if(b_check_boolean_expression(Pred,LocalState,InState,CWF,Res),
3617		(PredRes=Res,copy_wf_finish(WF,CWF)),
3618	?	b_try_check_boolean_expression_c2(Pred,LocalState,InState,WF,PredRes)
3619		).
3620		b_try_check_boolean_expression_c2(Pred,LocalState,InState,WF,pred_true) :-
3621		%hit_profiler:add_profile_hit(b_try_check_failed(Pred),3),
3622		b_test_inner_boolean_expression(Pred,LocalState,InState,WF).
3623		b_try_check_boolean_expression_c2(Pred,LocalState,InState,WF,pred_false) :-
3624		b_not_test_inner_boolean_expression(Pred,LocalState,InState,WF).
3625
3626
3627		% WHILE SUBSTITUTION TREATMENT:
3628
3629		:- if(environ(prob_noopt_mode,true)).
3630		get_while_reads_write_info_and_filter_state(Info,LocalState,InState,LS,IS,ModVars) :-
3631		member(modifies(ModVars),Info),!,
3632		LS=LocalState, IS=InState. % do not filter state
3633		:- endif.
3634		get_while_reads_write_info_and_filter_state(Info,LocalState,InState,LS,IS,ModVars) :-
3635	?	member(reads(ReadVars),Info),
3636	?	member(modifies(ModVars),Info),!,
3637		% we may go around the loop many times: avoid carrying around unused variables
3638		ord_union(ReadVars,ModVars,ReadOrModVars),
3639		filter_states(ReadOrModVars,LocalState,InState,LS,IS).
3640		get_while_reads_write_info_and_filter_state(Info,LocalState,InState,LS,IS,ModVars) :-
3641		add_internal_error('No reads & modifies info for while loop: ',get_while_reads_write_info_and_filter_state(Info,LocalState,InState,LS,IS,ModVars)),
3642		ModVars=_, % all variables assumed to be modified
3643		LS=LocalState, IS=InState.
3644
3645		unused_variable(List,bind(Var,_)) :-
3646		% b_is_variable(Var), % TO DO: also include constants in reads Info ?
3647		ord_nonmember(Var,List).
3648		unused_localvariable(List,bind(Var,Val)) :- ord_nonmember(Var,List),
3649		(nonvar(Val),Val=(_,_) -> atom_codes(Var,Codes), Codes \= [64|_] % not a lazy_let ID starting with @
3650		% 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 ?
3651		; true).
3652
3653		filter_states(ReadOrModVars,LocalState,InState,LS,IS) :-
3654		exclude(unused_localvariable(ReadOrModVars),LocalState,LS),
3655		exclude(unused_variable(ReadOrModVars),InState,IS).
3656		% TO DO: investigate whether we should use ord_intersect; ReadVars is already sorted
3657
3658		:- block lazy_exclude(-,?,?).
3659		lazy_exclude([],_,[]).
3660		lazy_exclude([bind(Var,Val)|T],ModVars,Res) :- lazy_exclude_aux(Var,Val,T,ModVars,Res).
3661		:- block lazy_exclude_aux(-,?,?,?,?).
3662		lazy_exclude_aux(Var,Val,T,ModVars,Res) :-
3663	?	(member(Var,ModVars) -> Res = [bind(Var,Val)|RT]
3664		; Res = RT),
3665		lazy_exclude(T,ModVars,RT).
3666
3667
3668		:- use_module(kernel_tools,[ground_state_check/2]).
3669		% outermost while code:; at next iteration b_execute_while1 will be called.
3670		:- block b_execute_while(?,?,?,?,?,-, ?,?,?, ?,?). % we block on Variant Value int(VarVal)
3671		b_execute_while(COND,STMT,INV,VARIANT,ModVars,int(VarVal),LocalState,InState,OutState,WF,BodyPath) :-
3672		%kernel_waitflags:get_idle_wait_flag(b_execute_while,WF,LWF),
3673		(number(VarVal),VarVal =< 50
3674		-> LWF=VarVal % we will wait anyway on GrInState below; no danger for WD issues in in b_optimize
3675		; no_pending_waitflags(WF) -> get_wait_flag0(WF,LWF) %important for e.g. PerformanceTests/While/LiftExec_LIM.mch
3676		; 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?
3677		% see also tests 979, 981
3678		),
3679		% before entering while loop, we wait for co-routines to complete that may have activated b_execute_while
3680		b_execute_while_idle(COND,STMT,INV,VARIANT,ModVars,int(VarVal),LocalState,InState,OutState,WF,LWF,BodyPath).
3681
3682		:- block b_execute_while_idle(?,?,?,?,?,?, ?,?,?, ?,-,?). % we block on enumeration starting wait_flag
3683		b_execute_while_idle(COND,STMT,INV,VARIANT,ModVars,int(VarVal),LocalState,InState,OutState,WF,_,BodyPath) :-
3684		%ground_constraintprop_wait_flags(WF),
3685		(number(VarVal), VarVal>50, preference(compile_while_body,true)
3686		% if VarVal > 50 -> worthwhile to compile STMT
3687		% TO DO: also take size of body into account, and what if only a small part of the body is reachable in each iteration
3688	?	-> b_compiler:b_optimize(STMT,ModVars,LocalState,InState,CSTMT,WF),
3689		% print(compiled_while(ModVars)),nl, translate:print_subst(CSTMT),nl,
3690		OutState=WhileOutState,
3691		exclude(unused_variable(ModVars),LocalState,LS), % only keep modified vars; all other compiled
3692		exclude(unused_variable(ModVars),InState,IS) % only keep modified vars; all other compiled
3693		; CSTMT=STMT, LS=LocalState, IS=InState,
3694		lazy_exclude(WhileOutState,ModVars,OutState) % only copy over those variables (potentially) modified by While loop
3695		% Note: it is important that we only have one copy of each modified variable in OutState
3696		),
3697		ground_state_check(InState,GrInState),
3698	?	b_execute_while_loop_block(GrInState,COND,CSTMT,INV,VARIANT,none,VarVal,LS,IS,WhileOutState,WF,BodyPath).
3699
3700		:- block b_execute_while_loop_block(-,?,?,?,?,?,?,?,?,?,?,?).
3701		b_execute_while_loop_block(_,COND,CSTMT,INV,VARIANT,none,VarVal,LS,IS,WhileOutState,WF,BodyPath) :-
3702		% the information passed to the outside is the number of iterations
3703	?	b_execute_while_loop(COND,CSTMT,INV,VARIANT,none,VarVal,LS,IS,WhileOutState,WF,while_bpath(0,none),BodyPath).
3704
3705		:- block b_execute_while1(?,?,?,?,?,-,?,?,?,?,?,?).
3706		b_execute_while1(COND,STMT,INV,VARIANT,PrevVariantValue,int(VarVal),LocalState,InState,OutState,WF,InPath,OutPath) :-
3707		% get_last_wait_flag(while(VarVal),WF,LWF),
3708		deref_wf(WF,FreshWF),
3709		%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
3710		% this can lead to enumeration warnings; the same applies to other calls to ground_constraintprop_wait_flags below
3711		b_execute_while_loop(COND,STMT,INV,VARIANT,PrevVariantValue,VarVal,LocalState,InState,OutState,FreshWF,InPath,OutPath).
3712
3713		% block on PrevVarVal and VarVal not yet needed here; but we need it for b_execute_while_body below
3714		:- block b_execute_while_loop(?,?,?,?,-,?,?,?,?,?,?,?), b_execute_while_loop(?,?,?,?,?,-,?,?,?,?,?,?).
3715		b_execute_while_loop(COND,STMT,INV,VARIANT,PrevVarVal,VarVal,LocalState,InState,OutState,WF,InPath,OutPath) :-
3716	?	b_try_check_boolean_expression_c(INV,LocalState,InState,WF,INVRes),
3717		%ground_constraintprop_wait_flags(WF), % seems to slow down interpretation
3718	?	b_check_execute_while_loop1(INVRes,COND,STMT,INV,VARIANT,PrevVarVal,VarVal,LocalState,InState,OutState,WF,InPath,OutPath).
3719
3720		:- block b_check_execute_while_loop1(-,?,?,?,?,?,?,?,?,?,?, ?,?).
3721		b_check_execute_while_loop1(pred_false,_COND,_STMT,INV,_VAR,_PrevVarVal,VarVal,LocalState,InState,_OutState,WF,P,P) :-
3722		add_abort_error_span(while_invariant_violation,
3723		'While INVARIANT VIOLATED, current VARIANT value: ',VarVal,span_predicate(INV,LocalState,InState),WF).
3724		b_check_execute_while_loop1(pred_true,COND,STMT,INV,VARIANT,PrevVarVal,VarVal,LocalState,InState,OutState,WF,InPath,OutPath) :-
3725		b_try_check_boolean_expression_c(COND,LocalState,InState,WF,CondRes),
3726		%ground_constraintprop_wait_flags(WF), % seems to slow down interpretation
3727	?	b_check_execute_while_loop2(CondRes,COND,STMT,INV,VARIANT,PrevVarVal,VarVal,LocalState,InState,OutState,WF,InPath,OutPath).
3728
3729		:- block b_check_execute_while_loop2(-,?,?,?,?,?,?,?,?,?,?, ?,?).
3730		b_check_execute_while_loop2(pred_false,_COND,_STMT,_INV,_VARIANT,_PrevVarVal,_VarVal,_LS,InState,OutState,_WF,P,P) :-
3731		OutState=InState. % we copy over the while InState: the updates will be computed at the end of the while loop
3732		b_check_execute_while_loop2(pred_true,COND,STMT,INV,VARIANT,PrevVarVal,VarVal,LocalState,InState,OutState,WF,InPath,OutPath) :-
3733
3734		%hit_profiler:add_profile_hit(b_execute_while_body(STMT,VarVal,PrevVarVal,LocalState),2),
3735		% TO DO: maybe only compute VARIANT now and not above ??
3736		% b_compute_expression(VARIANT,LocalState,InState,VarVal,WF),
3737		% ground_constraintprop_wait_flags(WF), %% moved here because VARIANT computed later
3738		inc_while_path(InPath,P1),
3739	?	b_execute_while_body(COND,STMT,INV,VARIANT,PrevVarVal,VarVal,LocalState,InState,OutState,WF,P1,OutPath).
3740
3741		% register in the event path that we have entered one more while iteration:
3742		inc_while_path(while_bpath(Cnt,LastIterPath),while_bpath(C1,LastIterPath)) :- C1 is Cnt+1.
3743		add_while_body_path(while_bpath(Cnt,_),Path1,Res) :-
3744		get_preference(eventtrace,true),!,
3745		Res = while_bpath(Cnt,Path1). % TODO: we could given a setting construct a sequence
3746		add_while_body_path(P,_,P).
3747
3748		%:- block b_execute_while_body(?,?,?,?,-,?,?,?,?,?,?,?), b_execute_while_body(?,?,?,?,?,-,?,?,?,?,?,?).
3749		% we must ensure VarVal and PrevVaraintValue known
3750		% the block declaration above for b_execute_while_loop already ensures this
3751		b_execute_while_body(_COND,_STMT,_INVARIANT,VAR,_PV,VarVal,LocalState,InState,_OutState,WF,Path,Path) :-
3752		VarVal<0, !, % more efficient than is_not_natural(int(VarVal)),
3753		%ground_constraintprop_wait_flags(WF),
3754		% add_abort_error_span will fail; hence no need to set _OutState
3755		add_abort_error_span(while_variant_error,'While VARIANT not NATURAL:',VarVal,span_predicate(VAR,LocalState,InState),WF).
3756		b_execute_while_body(_COND,_STMT,_INVARIANT,VAR,PrevVariantValue,VarVal,LocalState,InState,_OutState,WF,Path,Path) :-
3757		% check no longer required VarVal>=0,%is_natural(int(VarVal),WF),
3758		PrevVariantValue \= none,
3759		PrevVariantValue =< VarVal, !, %less_than_equal(int(PrevVariantValue),int(VarVal)),
3760		%ground_constraintprop_wait_flags(WF),
3761		% add_abort_error_span will fail; hence no need to set _OutState
3762		ajoin(['VARIANT = ',VarVal,', previous value = ',PrevVariantValue],Details),
3763		add_abort_error_span(while_variant_error,'While VARIANT not decreasing:',
3764		Details,span_predicate(VAR,LocalState,InState),WF).
3765		b_execute_while_body(COND,STMT,INV,VARIANT,_PrevVariantValue,VarVal,LocalState,InState,OutState,WF,InPath,OutPath) :-
3766		% check no longer required due to cuts above %VarVal>=0, %is_natural(int(VarVal),WF),
3767		%(PrevVariantValue==none -> true ; less_than(int(VarVal),int(PrevVariantValue))),
3768		%ground_constraintprop_wait_flags(WF), % seems to slow down interpretation
3769		copy_wf_start(WF,while_body,CWF),
3770	?	b_execute_statement(STMT,LocalState,InState,LHSUpdates,CWF,Path1,output_required),
3771		add_while_body_path(InPath,Path1,P1),
3772		copy_wf_finish(WF,CWF),
3773		ground_det_wait_flag(WF), % TODO: remove this
3774		store_intermediate_updates_wf(InState,LHSUpdates,IntermediateState,STMT,WF),
3775		check_state_skeleton_bound(LHSUpdates,Bound), % otherwise variable lookups will cause problems; ensures IntermediateState skeleton bound
3776		b_execute_while_when_state_set(COND,STMT,INV,VARIANT,VarVal,LocalState,IntermediateState,OutState,WF,Bound,P1,OutPath).
3777
3778		:- block b_execute_while_when_state_set(?,?,?,?,?,?,?,?,?,-,?,?).
3779		b_execute_while_when_state_set(COND,STMT,INV,VARIANT,PrevVariantValue,LocalState,State,Res,WF,_,InPath,OutPath) :-
3780		copy_wf_start(WF,while2,CWF),
3781		b_compute_expression(VARIANT,LocalState,State,VarVal,CWF),
3782		copy_wf_finish(WF,CWF),
3783		b_execute_while1(COND,STMT,INV,VARIANT,PrevVariantValue,VarVal,LocalState,State,Res,WF,InPath,OutPath).
3784
3785		% ------------- IF-THEN-ELSE
3786
3787		:- block b_execute_else_list2(-,?,?,?, ?,?,?,?,?,-,?). % should we also unblock if LWF set ? needed for seq. composition to set up state ??
3788		b_execute_else_list2(PredRes,Body,Rest,LocalState,InState,OutState,InnerWF,CaseNr,Path,LWF,OR) :-
3789		%(var(PredRes) -> print('IF-THEN-ELSE ENUMERATION: '), translate:print_subst(Body),nl ; true),
3790	?	b_execute_else_list3(PredRes,Body,Rest,LocalState,InState,OutState,InnerWF,CaseNr,Path,LWF,OR).
3791
3792		b_execute_else_list3(pred_true,Body,_,LocalState,InState,OutState,WF,CaseNr,if(CaseNr,Path),_,OR) :-
3793	?	push_wait_flag_call_stack_info(WF,b_expr_call(if_then_body,Body),WF2),
3794	?	b_execute_statement(Body,LocalState,InState,OutState,WF2,Path,OR).
3795		b_execute_else_list3(pred_false,_Body,Rest,LocalState,InState,OutState,WF,CaseNr,Path,LWF,OR) :-
3796		CaseNr1 is CaseNr+1,
3797	?	b_execute_else_list(Rest,LocalState,InState,OutState,WF,CaseNr1,Path,LWF,OR).
3798
3799		b_execute_else_list([],_,_State,[],_WF,_,if_skip,_LWF,_OR). /* skip */
3800		b_execute_else_list([TExpr|Rest],LocalState,InState,OutState,WF,CaseNr,Path,LWF,OR) :-
3801		get_texpr_expr(TExpr,if_elsif(Test,Body)), % Info field not used
3802		% get_enumeration_finished_wait_flag(WF,LWF),
3803		InnerWF=WF, %clone_wait_flags_from1(WF,InnerWF),
3804		push_wait_flag_call_stack_info(InnerWF,b_expr_call(if_elsif_test,Test),WF2),
3805	?	b_try_check_boolean_expression_lwf(Test,LocalState,InState,WF2,'$ENUMERATION',PredRes,LWF),
3806		%ground_wait_flag0(InnerWF),
3807		(nonvar(PredRes)
3808		-> b_execute_else_list3(PredRes,Body,Rest,LocalState,InState,OutState,InnerWF,CaseNr,Path,LWF,OR)
3809		; (LWF == '$GENERATE_ON_DEMAND' ->
3810		get_wait_flag0(WF,LWF1),
3811		get_wait_flag_if_necessary(PredRes,LWF1,OR,WF,LWF2)
3812		; LWF2=LWF),
3813	?	b_execute_else_list2(PredRes,Body,Rest,LocalState,InState,OutState,InnerWF,CaseNr,Path,LWF2,OR)
3814		).
3815
3816		% avoid calling get_wait_flag if possible (expensive)
3817		:- block get_wait_flag_if_necessary(-,-,?,?,?).
3818		get_wait_flag_if_necessary(PredRes,_,OR,WF,LWF2) :- var(PredRes), !, % we need waitflag
3819		(preferences:preference(use_smt_mode,true) -> Prio = 2 % was 2.0
3820		; OR == output_required -> Prio = 2000
3821		; Prio = 200000 %last_finite_priority(Prio)
3822		), % TO DO: check if there is a guard inside; if not we can wait much longer; unless we are in CBC mode
3823		get_wait_flag(Prio,if_else,WF,LWF2).
3824		get_wait_flag_if_necessary(_,_,_,_,_).
3825
3826		:- block b_execute_choice(?,?,?,?,?,?,-,?).
3827		b_execute_choice(ChoiceList,LocalState,InState,OutState,WF,choice(Nr,Path),_WFC,OR) :-
3828	?	nth1(Nr,ChoiceList,Choice),
3829		b_execute_statement(Choice,LocalState,InState,OutState,WF,Path,OR).
3830
3831		% execute ASSERT PreCond THEN Body
3832		b_execute_assertion(_PreCond,Body,LocalState,InState,OutState,WF,Path,OR) :-
3833		preference(do_assert_checking,false), % ASSERT checking disabled
3834		!,
3835		b_execute_statement(Body,LocalState,InState,OutState,WF,Path,OR).
3836		b_execute_assertion(PreCond,Body,LocalState,InState,OutState,WF,Path,OR) :-
3837	?	b_try_check_boolean_expression_lwf(PreCond,LocalState,InState,WF,'$ENUMERATION',PredRes,WFC),
3838		% enumeration of PredRes before WFE set make sense, Body can instantiate values
3839		(var(PredRes) -> get_last_wait_flag(assertion,WF,WFC) ; true),
3840		b_execute_assertion_block(PredRes,PreCond,Body,LocalState,InState,OutState,WF,Path,OR).
3841
3842		:- block b_execute_assertion_block(-, ?,?,?,?, ?,?,?,?).
3843		b_execute_assertion_block(pred_true,_PreCond,Body,LocalState,InState,OutState,WF,Path,OR) :-
3844		Path = assertion(IPath),
3845		b_execute_statement(Body,LocalState,InState,OutState,WF,IPath,OR).
3846		b_execute_assertion_block(pred_false,PreCond,_Body,LocalState,InState,_OutState,WF,Path,_OR) :-
3847		Path = assertion_violated,
3848		translate_bexpression(PreCond,PreString),
3849		add_abort_error_span(assert_error,'ASSERT violated: ',PreString,span_predicate(PreCond,LocalState,InState),WF).
3850
3851		:- block check_state_skeleton_bound(-,?).
3852		check_state_skeleton_bound([],true).
3853		check_state_skeleton_bound([bind(Var,_)|T],Res) :-
3854		check_state_skeleton_bound_aux(Var,T,Res).
3855
3856		:- block check_state_skeleton_bound_aux(-,?,?).
3857		check_state_skeleton_bound_aux(Var,T,Res) :-
3858		(atomic(Var) -> true ; print('*** variable name not atomic: '), print(Var),nl),
3859		check_state_skeleton_bound(T,Res).
3860
3861
3862		b_execute_statement_list_when_state_set(StmtList,LS,State,USoFar,Res,WF,Path,OR) :-
3863		check_state_skeleton_bound(State,Bound), % otherwise variable lookups will cause problems
3864	?	b_execute_statement_when_state_set2(StmtList,LS,State,USoFar,Res,WF,Path,Bound,OR).
3865		:- block b_execute_statement_when_state_set2(?,?,?,?,?,?,?,-,?).
3866		b_execute_statement_when_state_set2(StmtList,LS,State,UpdatesSofar,Res,WF,Path,_,OR) :-
3867		copy_wf_start(WF,while2,CWF),
3868	?	b_execute_sequence(StmtList,LS,State,StmtUpdates,CWF,Path,OR),
3869	?	copy_wf_finish(WF,CWF),
3870	?	merge_updates(UpdatesSofar,StmtUpdates,Res).
3871
3872
3873		store_values([], [], []).
3874		store_values([IDsHd|IDsTl], [VALsHd|VALsTl], [bind(IDsHd,VALsHd)|OutStateTl]) :-
3875		store_values(IDsTl, VALsTl, OutStateTl).
3876
3877
3878
3879
3880		/* the B syntax does allow multiple definitions in a LET: */
3881
3882		b_execute_let_definitions(Pred,LocalState,State,WF) :-
3883		is_a_conjunct(Pred,LHS,RHS),!,
3884		b_execute_let_definitions(LHS,LocalState,State,WF),
3885		b_execute_let_definitions(RHS,LocalState,State,WF).
3886		b_execute_let_definitions(b(equal(LHS,RHS),_,_),LocalState,State,WF) :- !,
3887		b_compute_expression(LHS,LocalState,State,LHSVal,WF),
3888		b_compute_expression(RHS,LocalState,State,RHSVal,WF),
3889		% TO DO: ideally we should check if LHS is a declared identifier and is only defined once
3890		kernel_objects:equal_object_optimized(LHSVal,RHSVal,b_execute_let_definitions).
3891		b_execute_let_definitions(b(lazy_let_pred(Id,AssignmentExpr,Body),_,_),LocalState,State,WF) :- !,
3892		add_lazy_let_id_and_expression(Id,AssignmentExpr,LocalState,State,NewLocalState,WF),
3893		b_execute_let_definitions(Body,NewLocalState,State,WF).
3894		b_execute_let_definitions(P,_L,_S,WF) :-
3895		add_internal_error_wf(b_interpreter,'Let contains a predicate which is not an equality: ',P,P,WF),fail.
3896
3897
3898		/* -----------------------------------------*/
3899		/* b_assign_function */
3900		/* -----------------------------------------*/
3901
3902		b_assign_values_or_functions([],[],_LS,_S,[],_WF,_OR).
3903		b_assign_values_or_functions([TExpr|ERest],[Value|VRest],LS,S,[bind(Id,New)|NRest],WF,OR) :-
3904		get_texpr_expr(TExpr,Expr),
3905	?	b_assign_value_or_function(Expr,Value,LS,S,Id,New,WF,OR),
3906		b_assign_values_or_functions(ERest,VRest,LS,S,NRest,WF,OR).
3907
3908		:- use_module(kernel_tools,[ground_value_check/2]).
3909		:- use_module(kernel_records,[overwrite_record_wf/5]).
3910		b_assign_value_or_function(identifier(Id),Value,_LS,_S,LHS_Id,FullValue,WF,_OR) :- !,
3911		LHS_Id=Id,
3912	?	equal_object_wf(FullValue,Value,b_assign_value_or_function(Id),WF).
3913		b_assign_value_or_function(function(Fun,Arg),Value,LocalState,InState,Id,FullValue,WF,OR) :- !,
3914		%b_compute_expression(Arg,LocalState,InState,ArgVal,WF),
3915		%expand_global_sets_but_not_closures(ArgVal,EArgVal),
3916		FunMNF = eval_must_not_fail('Assignment left-hand-side (or part thereof) could not be evaluated: ',Fun), % could be f(..)(..)
3917		b_compute_assign_expressions_when([Arg,FunMNF],LocalState,InState,[ArgVal,FunVal],WF,OR), % or should we pass the OR info around ?
3918		/* we do not examine local state: these vars cannot be modified by operations !? */
3919		(OR=output_required -> override(FunVal,ArgVal,Value,NewFun,WF)
3920		; ground_value_check((FunVal,ArgVal,Value),GRV),
3921		% wait until all arguments known so that we can effiently compute override
3922		blocking_override(GRV,FunVal,ArgVal,Value,NewFun,WF)),
3923		get_texpr_expr(Fun,Lhs),
3924		b_assign_value_or_function(Lhs,NewFun,LocalState,InState,Id,FullValue,WF,OR).
3925		b_assign_value_or_function(record_field(RecordExpr,FieldName),Value,LocalState,InState,LHS_Id,FullValue,WF,OR) :-
3926		!,
3927		% we allow nested record assignments: x'Field1'Field2 := Value
3928		b_compute_expression(RecordExpr,LocalState,InState,OldRecVal,WF),
3929		overwrite_record_wf(OldRecVal,FieldName,Value,NewRecVal,WF),
3930		get_texpr_expr(RecordExpr,Lhs),
3931		b_assign_value_or_function(Lhs,NewRecVal,LocalState,InState,LHS_Id,FullValue,WF,OR).
3932		b_assign_value_or_function(LHS,_Value,_LS,_InState,_Id,_FullValue,WF,_OR) :-
3933		add_internal_error_wf(b_interpreter,'Illegal LHS for assignment (must be ID(.) or ID\'Field or ID): ',LHS,LHS,WF),
3934		fail.
3935
3936		:- block blocking_override(-,?,?,?,?,?).
3937		blocking_override(_,FunVal,ArgVal,Value,NewFun,WF) :- override(FunVal,ArgVal,Value,NewFun,WF).
3938
3939
3940		/* -----------------------------------------*/
3941		/* b_execute_statements_in_parallel */
3942		/* -----------------------------------------*/
3943		/* execute a parallel composition of statements */
3944		:- assert_pre(b_interpreter:b_execute_statements_in_parallel(Ss,LS,State,_Os,WF,_Paths,_OR),
3945		(ground_check(Ss),type_check(LS,store),
3946		type_check(State,store),type_check(WF,wait_flag))).
3947		:- assert_post(b_interpreter:b_execute_statements_in_parallel(_Ss,_LS,_State,Os,WF,_Paths,_OR),
3948		(type_check(Os,store),type_check(WF,wait_flag))).
3949
3950		b_execute_statements_in_parallel([],_,_,[],_WF,[],_OR).
3951		b_execute_statements_in_parallel([Stmt|TS],LocalState,InState,OutState,WF,[Path1|TPath],OR) :-
3952	?	b_execute_statement(Stmt,LocalState,InState,OutState1,WF,Path1,OR),
3953	?	combine_updates(OutState1,OutState2,OutState), /* merge updates */
3954	?	b_execute_statements_in_parallel(TS,LocalState,InState,OutState2,WF,TPath,OR).
3955
3956
3957		%:- block combine_updates(-,-,?).
3958		%combine_updates(A,B,C) :- (B==[] -> A=C ; combine_updates_aux(A,B,C)).
3959
3960		% TO DO: investigate whether we could also unblock on second argument and copy it to result
3961		:- block combine_updates(-,?,?). % can also be used to merge states
3962		combine_updates([],X,R) :- !,R=X.
3963	?	combine_updates([H|T],Y,Res) :- !, Res=[H|Z], combine_updates(T,Y,Z).
3964		combine_updates(X,Y,Z) :- add_internal_error('Illegal call: ',combine_updates(X,Y,Z)),fail.
3965
3966
3967
3968		b_execute_initialisation_statement(Stmt,LS,In,Out,_OUTERWF,Path,OR) :-
3969		init_wait_flags(WF,[b_execute_initialisation_statement]),
3970		% each initialisation can be executed in isolation (except in CBC mode)
3971	?	b_execute_statement(Stmt,LS,In,Out,WF,Path,OR),
3972	?	ground_wait_flags(WF).
3973
3974		% replace certain parallels by init_parallel for better error reporting in INITIALISATION
3975		% will not be used in CBC mode (by set_up_initialisation or tc_initialise)
3976		translate_init_statements(b(Stmt,subst,I),b(TStmt,subst,I)) :-
3977		tp2(Stmt,I,TStmt).
3978		tp2(assign(LHS,RHS),I,parallel(S)) :- LHS=[_,_|_],
3979		% translate multiple assignment into parallel assignments
3980		maplist(generate_assignment(I),LHS,RHS,S),
3981		!.
3982		tp2(Stmt,I,init_statement(b(Stmt,subst,I))) :- %get_preference(provide_trace_information,true),
3983		wrap_stmt(Stmt),
3984		!.
3985		% TO DO: cover WHILE
3986		tp2(parallel(S),_,parallel(TS)) :- maplist(translate_init_statements,S,TS),
3987		!.
3988		tp2(sequence(A),_,sequence(LA)) :- !,maplist(translate_init_statements,A,LA).
3989		tp2(if(A),_,if(LA)) :- !, maplist(translate_init_statements,A,LA).
3990		tp2(if_elsif(Test,Body),_,if_elsif(Test,LBody)) :- !,
3991		translate_init_statements(Body,LBody).
3992		tp2(X,_,X). % :- functor(X,F,A), nl,nl,print(uncovered(F/A)),nl,nl.
3993
3994		wrap_stmt(assign(_,_)).
3995		wrap_stmt(becomes_element_of(_,_)).
3996		wrap_stmt(becomes_such(_,_)).
3997		wrap_stmt(assign_single_id(_,_)).
3998
3999		generate_assignment(I,V,RHS,b(init_statement(b(Assign,subst,I)),subst,I)) :-
4000		Assign = assign([V],[RHS]).
4001
4002
4003
4004		/* ---------------------------------------*/
4005		/* b_execute_top_level_statement */
4006		/* ---------------------------------------*/
4007
4008		/* this is just like b_execute_statement with the
4009		only difference that a PRE-condition is treated like
4010		a select, i.e., it does not generate an abort if used
4011		outside of its condition */
4012		b_execute_top_level_statement(TExpr,LocalState,InState,OutState,WF,Path,OR) :-
4013		get_texpr_expr(TExpr,Stmt),
4014	?	b_execute_top_level_statement2(Stmt,TExpr,LocalState,InState,OutState,WF,Path,OR).
4015		b_execute_top_level_statement2(precondition(PreCond,Body),TExpr,
4016		LocalState,InState,OutState,WF,Path,OR) :-
4017		preferences:preference(treat_outermost_pre_as_select,true),!,
4018		%debug_println(9,'Top level PRE treated as SELECT'),
4019		preference(ltsmin_do_not_evaluate_top_level_guards,NO_EVAL),
4020		(NO_EVAL=true, % do not evaluate guards detected by guard splitting
4021		get_texpr_info(TExpr,Info),member(prob_annotation('LTSMIN-GUARD'),Info)
4022		-> debug_println(9,ltsmin_guard_will_not_be_evaluated)
4023	?	; b_test_boolean_expression(PreCond,LocalState,InState,WF)
4024		),
4025		% b_tracetest_boolean_expression(PreCond,LocalState,InState,WF,one), % comment in for debugging
4026	?	b_execute_statement(Body,LocalState,InState,OutState,WF,Path,OR).
4027		b_execute_top_level_statement2(lazy_let_subst(Id,IdExpr,Body),_,
4028		LocalState,InState,OutState,WF,lazy_let(Path),OR) :-
4029		!,
4030		add_lazy_let_id_and_expression(Id,IdExpr,LocalState,InState,NewLocalState,WF),
4031		b_execute_top_level_statement(Body,NewLocalState,InState,OutState,WF,Path,OR).
4032		b_execute_top_level_statement2(_,TExpr,LocalState,InState,OutState,WF,Path,OR) :-
4033	?	b_execute_statement(TExpr,LocalState,InState,OutState,WF,Path,OR).
4034
4035
4036		/* -----------------------------*/
4037		/* b_execute_operation */
4038		/* -----------------------------*/
4039		/* execute a single operation */
4040
4041		try_get_op_name(FullOperation,_Name) :- var(FullOperation),!.
4042		try_get_op_name('-->'(FO,_),Name) :- !,try_get_op_name(FO,Name).
4043		try_get_op_name(FullOperation,Name) :- functor(FullOperation,Name,_).
4044
4045
4046
4047		:- assert_pre(b_interpreter:b_execute_top_level_operation_update(_Name,_FullOperation,InState,_NewState,_P),
4048		(ground_check(InState),type_check(InState,store))).
4049		:- assert_post(b_interpreter:b_execute_top_level_operation_update(Name,_FullOperation,_InState,NewState,_Path),
4050		(type_check(NewState,store),ground_check(Name))).
4051
4052
4053		b_execute_top_level_operation_update(Name,FullOperation,InState,Updates,Path) :-
4054	?	b_execute_top_level_operation_update_wf(Name,FullOperation,InState,Updates,Path,WF),
4055	?	ground_wait_flags(WF).
4056		%store:store_updates_and_normalise(Updates,InState,NewState).
4057
4058
4059		b_execute_top_level_operation_update_wf(Name,FullOperation,InState,Updates,Path,WF) :-
4060		init_wait_flags(WF,[]), % now treated by call_stack: [expansion_context(op(Name),[])]),
4061		% b_execute_operation2 below will push_wait_flag_call_stack_info
4062		try_get_op_name(FullOperation,Name), b_top_level_operation(Name),
4063		setup_result_input_values(Name,RIV),
4064		Info=unknown, % Info extracted later for top_level
4065	?	b_execute_operation2(Name,FullOperation,InState,Updates,_,RIV,_,true,Path,Info,WF,output_not_required).
4066
4067		% set up value of read output variables *before* operation call to some dummy value
4068		setup_result_input_values(Name,ResultInputValues) :-
4069		(get_preference(allow_operations_to_read_outputs,true),
4070		b_operation_reads_output_variables(Name,_Reads,TReadsInfo) ->
4071		maplist(setup_read_output_variable,TReadsInfo,ResultInputValues)
4072		%translate_bstate_limited(ResultInputValues,TS),
4073		%ajoin(['Warning: setting read output variables in ',Name,' to default values: ',TS],Msg),
4074		%add_warning(b_interpreter,Msg),
4075		%store_error_for_context_state(eventerror(Name,event_other_error(Msg),[]),_Id)
4076		; ResultInputValues=[]).
4077
4078		:- use_module(typing_tools,[any_value_for_type/2]).
4079		setup_read_output_variable(reads_result(_,Name,Type),bind(Name,Val)) :- any_value_for_type(Type,Val).
4080
4081		% for use by CBC:
4082		b_execute_top_level_operation_wf(Name,FullOperation,ParaVals,ResultVals,InState,NewState,Path,WF) :-
4083		try_get_op_name(FullOperation,Name),
4084		if(b_top_level_operation(Name),true,
4085		(add_internal_error('Unknown operation name for b_execute_top_level_operation_wf: ',Name),fail)
4086		),
4087		% call before execute operation to copy over results immediately in case b_execute_operation2 generates choice points:
4088		store_intermediate_updates_wf(InState,Updates,NewState,operation(Name),WF), % no normalising is better for constraint propagation
4089		% TO DO?: copy over unmodified variables b_get_machine_variables(Variables),copy_unmodified_variables(Variables,OpName,InState,NewState)
4090		setup_result_input_values(Name,RIV),
4091		Info=unknown, % Info extracted later for top_level
4092		b_execute_operation2(Name,FullOperation,InState,Updates,ParaVals,RIV,ResultVals,true,Path,Info,WF,output_required).
4093		% we should ensure that Operation part is executed to instantiate NewOutState skeleton
4094
4095
4096
4097		% Note : if the argument OR (OutputRequired) has value output_required this indicates that the output
4098		% an operation or its effect is required (e.g., because of sequential composition) and the constraint solver
4099		% should not delay computing the effect of the operation
4100		% Atelier-B Handbook 6.16: [R <- op (E)]P = [X := E ; S ; R :=Y] P where op defined by X <- op(Y) = S
4101		b_execute_operation_with_parameters(Name,LocalState,InState,Results,Parameters,OutState,ParamValues,ResultValues,
4102		Path,Info,WF,OR) :-
4103		(b_is_operation_name(Name)
4104		-> b_compute_expressions(Parameters,LocalState,InState,ParamValues,WF),
4105		% TO DO : remove local vars from InState
4106		(b_operation_reads_output_variables(Name,_Reads,TReadsInfo)
4107		-> % format('Transferring outputs ~w ~w~n ~w~n',[Name,_Reads,TReadsInfo]),
4108		maplist(output_parameters_value(LocalState,InState,Results,Info,WF),TReadsInfo,ResultInputValues)
4109		; ResultInputValues=[]),
4110	?	call_b_execute_operation2(Name,InState,OutState,ParamValues,ResultInputValues,ResultValues,false,
4111		Path,Info,WF,OR)
4112		; add_internal_error('Unknown B operation, cannot call: ',
4113		b_execute_operation_with_parameters(Name,LocalState,InState,Results,Parameters,
4114		OutState,ParamValues,ResultValues,Path,Info,WF,OR)),
4115		fail
4116		).
4117
4118
4119		%b_execute_operation_in_expression(Name,_LocalState,_InState,_Parameters,_Value,Info,_WF) :-
4120		% % This clause is disabled: sometimes variables are marked as read even though they are not:
4121		% % the analysis is not precise due to sequential composition, CASE statements, ...
4122		% b_operation_reads_output_variables(Name,_Reads,_TReadsInfo),!,
4123		% add_error(b_interpreter,'Operation that reads output cannot be called in expression: ',Name,Info),
4124		% fail.
4125		b_execute_operation_in_expression(Name,LocalState,InState,Parameters,Value,Info,WF) :-
4126		% TODO: check that this is a query operation; probably done in type checker
4127		OR=output_required, % alternative: OR=output_not_required,
4128		setup_result_input_values(Name,ResultInputValues),
4129		b_compute_expressions(Parameters,LocalState,InState,ParamValues,WF),
4130		(b_get_operation_normalized_read_write_info(Name,Read,_Modified)
4131		-> true % Modified should be []
4132		; member(reads(Read),Info)
4133		-> add_message(b_interpeter,'Unregistered operation in expression: ',Name) % prefixed operation not found
4134		; add_error(b_interpeter,'Cannot obtain read-write info for operation in expression:',Name),
4135		Read=[]
4136		),
4137		create_inner_wait_flags(WF,operation_call_in_expr,OpWF),
4138		ground_value_check(ParamValues,ParaGround),
4139		exclude(unused_variable(Read),InState,IS),
4140		ground_state_check(IS,StateGround),
4141		% TO DO: in case of recursion it may be good to delay executing sub-operation until some WF is set
4142		call_b_execute_operation2(Name,IS,_OutState,ParamValues,ResultInputValues,ResultValues,false,_Path,Info,OpWF,OR),
4143		ground_inner_wf(ParaGround,StateGround,OpWF),
4144		make_couplise(ResultValues,Value).
4145
4146		% ground inner waitflags when parameters and relevant read variables fully known
4147		:- block ground_inner_wf(-,?,?), ground_inner_wf(?,-,?).
4148		ground_inner_wf(_,_,WF) :-
4149	?	ground_inner_wait_flags(WF).
4150
4151		call_b_execute_operation2(Name,InState,OutState,ParamValues,ResultInputValues,ResultValues,false,Path,Info,WF,OR) :-
4152	?	runtime_profiler:profile_single_call(Name,unknownStateId, b_interpreter:
4153		b_execute_operation2(Name,_,InState,OutState,ParamValues,ResultInputValues,ResultValues,false,Path,Info,WF,OR)
4154		).
4155
4156		output_parameters_value(LocalState,InState,Results,_,WF,reads_result(Index,ID,_Type),bind(ID,Val)) :-
4157		nth1(Index,Results,ReadResultTID),!,
4158		def_get_texpr_id(ReadResultTID,ReadID),
4159		(lookup_value_without_check(ReadID,LocalState,InState,Val)
4160		-> true %check_not_undefined(Val,ReadID,ReadResultTID)
4161		; add_error_wf(output_parameters,'Could not obtain value for read output parameter: ',ReadID,ReadResultTID,WF),
4162		Val = term(undefined)).
4163		output_parameters_value(_LocalState,_InState,_Results,Info,WF,reads_result(_Index,ID,_Type),bind(ID,Val)) :-
4164		add_error_wf(output_parameters,'Could not obtain value for read output parameter: ',ID,Info,WF),
4165		Val = term(undefined).
4166
4167		% TO DO: use this ?
4168		%:- block check_not_undefined(-,?,?).
4169		%check_not_undefined(term(undefined),ReadID,ReadResultTID) :- !,
4170		% add_error(output_parameters_value,'Output parameter not assigned to: ',ReadID,ReadResultTID).
4171		%check_not_undefined(_,_,_).
4172
4173		:- use_module(probsrc(succeed_max),[assert_max_reached/1]).
4174		% ResultInputValues: in Atelier-B result parameters can also be read !
4175		b_execute_operation2(Name,Operation,InState,Updates,ParaValues,ResultInputValues,ResultValues,_TopLvl,TransInfo,_,_WF,_OR) :-
4176		ResultInputValues = [], % in this case the operation's behaviour also depends on current value of output variables
4177		lookup_cached_transitions(Name,InState,Info,Solutions),!,
4178		(member(max_reached,Info) -> assert_max_reached(Name) ; true),
4179	?	member(trans_cached(ParaValues,ResultValues,Updates,TransInfo),Solutions),
4180		create_full_operation(Name,ResultValues,ParaValues,ResultValues,Operation).
4181		% TODO: call operation with ParaValues if not found and max_reached is true !!
4182
4183		b_execute_operation2(Name,Operation,InState,NewOutState,ParaValues,ResultInputValues,ResultValues,
4184		TopLevel,TransInfo,Info,WF,OutputRequired) :-
4185		if(b_get_machine_operation_for_animation(Name,Results,Parameters,Body,OType,TopLevel,OpPos),
4186		true,
4187		(add_error_wf(b_interpreter,'Cannot find operation:',Name,Info,WF),fail)),
4188		%% % we do not want skip the evaluation of a guard of an operation with parameters
4189		(Info=unknown, TopLevel==true -> CallInfo=OpPos ; CallInfo=Info),
4190		push_wait_flag_call_stack_info(WF,operation_call(Name,ParaValues,CallInfo),WF2),
4191	?	b_execute_operation3(OType,Name,Operation,
4192		InState,NewOutState,
4193		Body,Parameters,ParaValues,Results,ResultInputValues,ResultValues,TopLevel,TransInfo,WF2,OutputRequired).
4194
4195		create_full_operation(Name,Results,ParaValues,ResultValues,FullOperation) :-
4196		Operation =.. [Name|ParaValues], % TO DO: catch if > 255 args (max_arity)
4197		( Results == [] -> /* we have an ordinary operation */
4198		FullOperation = Operation
4199		; FullOperation = '-->'(Operation,ResultValues)
4200		).
4201
4202		b_execute_operation3(classic,Name,Operation,InState,NewOutState,
4203		Body,Parameters,ParaValues,Results,ResultInputValues,NormalisedResultValues,TopLevel,
4204		[path(Path)], % as path is currently filtered out anyway and not stored !
4205		WF,OR) :-
4206		%print('Attempting Operation ----> '),print(Name),nl,
4207		empty_state(EmptyState),
4208	?	set_up_typed_localstate(Parameters,ParaValues,ParamTypedVals,EmptyState,LocalState,positive),
4209		l_expand_and_normalise_values(ParaValues,NormalisedParaValues,Parameters),
4210		% not useful for call_b_execute_operation2
4211		create_full_operation(Name,Results,NormalisedParaValues, % ditto
4212		NormalisedResultValues,Operation),
4213		set_up_undefined_localstate_with_predefined(Results,ResultInputValues,InState,NewInState),
4214		/* to avoid error messages with sequential composition (store_intermediate_updates) */
4215		check_additional_guard(TopLevel,LocalState,NewInState,WF),
4216		(TopLevel==true
4217	?	-> b_execute_top_level_statement(Body,LocalState,NewInState,OutState,WF,Path,OR)
4218	?	; b_execute_statement(Body,LocalState,NewInState,OutState,WF,Path,OR)
4219		),
4220		b_tighter_enumerate_all_values(ParamTypedVals,WF),
4221		% moved after execute for performance reasons; see PerformanceTests/ParameterEnumeration.mch
4222		% print_bt_message('Operation Successful ------> '),
4223		(preferences:preference(treat_outermost_pre_as_select,true),
4224		preferences:preference(require_operations_to_assign_all_outputs,true)
4225		-> ReportError = true ; ReportError = false),
4226		get_results(Results,OutState,NormalisedResultValues,NewOutState,ReportError,normalise_results,WF).
4227		b_execute_operation3(eventb_operation(ChangeSet,ParaValues,Operation),
4228		_Name,Operation, InState,Updates,
4229		TBody,Parameters,ParaValues,[],[],[],true,TransInfo,WF,OutputRequired) :-
4230		% TO DO: check if need to pass _OutputRequired to b_event
4231	?	b_execute_event_with_change_set_wf(TBody,Parameters,ParaValues,InState,ChangeSet,Updates,TransInfo,WF,OutputRequired).
4232
4233		:- use_module(b_global_sets,[add_prob_deferred_set_elements_to_store/3]).
4234		% additional guards can be set by the user to constrain/direct the execution of operations
4235		check_additional_guard(TopLevel,LocalState,State,WF) :-
4236		(TopLevel==true,
4237		bmachine:b_machine_temp_predicate(TempPred)
4238		/* an additional precondition typed in by the user */
4239		-> check_state_skeleton_bound(LocalState,LB),
4240		check_state_skeleton_bound(State,BB),
4241		check_additional_guard_when_bound(LB,BB,TempPred,LocalState,State,WF)
4242		; true
4243		).
4244
4245		:- block check_additional_guard_when_bound(-,?,?, ?,?,?), check_additional_guard_when_bound(?,-,?, ?,?,?).
4246		check_additional_guard_when_bound(_,_,TempPred,LocalState,State,WF) :-
4247		(debug_mode(on) -> print(check_additional_guard),nl, print_bexpr(TempPred),nl ; true),
4248		add_prob_deferred_set_elements_to_store(State,BState1,visible),
4249		b_test_boolean_expression(TempPred,LocalState,BState1,WF).
4250
4251		% additional properties can either be set by user or by command-line or by VALUES clause
4252		add_additional_properties(OldProperty,NewProperty) :-
4253		(bmachine:b_machine_temp_predicate(TempPred) % this overrides additional property !
4254		-> conjunct_predicates([TempPred,OldProperty],NewProperty)
4255		; findall(AddPred,b_machine_additional_property(AddPred),L),
4256		(L=[] -> NewProperty = OldProperty
4257		; conjunct_predicates([OldProperty|L],NewProperty)
4258		)
4259		).
4260
4261		% get removes results from OutState
4262		filter_results(Results,OutState,NewOutState,WF) :-
4263		get_results(Results,OutState,_ResultValues,NewOutState,false,do_not_normalise,WF).
4264		get_results(Results,OutState,ResultValues,NewOutState,ReportError,Normalise,WF) :-
4265		(Results==[] -> (ResultValues,NewOutState) = ([],OutState)
4266		; get_results1(Results,OutState,ResultValues,NewOutState,ReportError,Normalise,WF)).
4267		:- block get_results1(?,-,?,?,?,?,?).
4268		get_results1([],OutState,[],OutState,_ReportError,_Normalise,_WF).
4269		get_results1([R|Results],OutState,[NRV|ResultValues],NewOutState,ReportError,Normalise,WF) :-
4270		def_get_texpr_id(R,ResultId),
4271		lookup_and_delete_value(ResultId,RV,OutState,OutState2,ReportError,WF,Finished),
4272		get_results2(Finished,R,Results,RV,NRV,OutState2,ResultValues,NewOutState,ReportError,Normalise,WF).
4273		:- block get_results2(-,?,?,?,?,?,?,?,?,?,?).
4274		get_results2(_,R,Results,RV,NRV,OutState2,ResultValues,NewOutState,ReportError,Normalise,WF) :-
4275		(Normalise==normalise_results -> normalise_value_for_var(R,true,RV,NRV)
4276		;
4277		NRV=RV), % Maybe we should not normalise in CBC mode ?
4278		get_results1(Results,OutState2,ResultValues,NewOutState,ReportError,Normalise,WF).
4279
4280
4281
4282		/* ------------------------------------------------------------------ */
4283		/* SET UP CONSTANTS */
4284		/* ------------------------------------------------------------------ */
4285
4286		:- use_module(static_ordering).
4287
4288		:- volatile no_solution_found_for_constants/0, properties_were_filtered/1,
4289		unsat_properties_component/2, unsat_properties_enumeration_warning/1, unsat_properties_abort_error/1,
4290		unsat_properties_conjunct_inside_component/4.
4291		:- dynamic no_solution_found_for_constants/0,
4292		properties_were_filtered/1,
4293		unsat_properties_component/2, unsat_properties_enumeration_warning/1,
4294		unsat_properties_abort_error/1,
4295		unsat_properties_conjunct_inside_component/4.
4296
4297		reset_unsat_component_infos :-
4298		retractall(unsat_properties_component(_,_)),
4299		retractall(unsat_properties_enumeration_warning(_)),
4300		retractall(unsat_properties_abort_error(_)),
4301		retractall(unsat_properties_conjunct_inside_component(_,_,_,_)).
4302
4303		:- use_module(b_interpreter_components,[unsat_conjunct_inside_component/4, unsat_component_abort_error/1,
4304		unsat_component_enumeration_warning/1]).
4305		% store information about unsatisfiable components for later usage
4306		% will only be called when no solution found for components
4307		assert_unsat_component_infos(_) :-
4308		unsat_component(X,FalseOrUnknown), % from b_interpreter_components
4309		assertz(unsat_properties_component(X,FalseOrUnknown)),fail.
4310		assert_unsat_component_infos(_) :-
4311		unsat_component_enumeration_warning(X), % from b_interpreter_components
4312		assertz(unsat_properties_enumeration_warning(X)),fail.
4313		assert_unsat_component_infos(_) :-
4314		unsat_component_abort_error(X), % from b_interpreter_components
4315		assertz(unsat_properties_abort_error(X)),fail.
4316		assert_unsat_component_infos(_) :-
4317		unsat_conjunct_inside_component(X,BE,Status,Reason), % from b_interpreter_components
4318		assertz(unsat_properties_conjunct_inside_component(X,BE,Status,Reason)),fail.
4319		assert_unsat_component_infos(Status) :-
4320		(unsat_conjunct_inside_component(_,_,false,_) -> Status = false
4321		; unsat_component(X,false), \+ unsat_component_abort_error(X) -> Status = false % what about enumeration warnings?
4322		; Status=unknown).
4323
4324
4325		all_unsat_components_marked_prob_ignore :-
4326		unsat_properties_conjunct_inside_component(_,_,unknown,'prob-ignore'), % at least one prob-ignore was used
4327		!,
4328		\+ non_ignore_unsat_component.
4329
4330		non_ignore_unsat_component :-
4331		unsat_properties_conjunct_inside_component(_,_,Status,Reason),
4332		\+ (Status = unknown, Reason = 'prob-ignore').
4333
4334		tcltk_unsatisfiable_components_exist :- unsat_or_unknown_component_exists,!.
4335
4336		%tcltk_unsatisfiable_components(list(UnsatComponents)) :-
4337		% findall(C,unsat_properties_component(C),UnsatComponents), UnsatComponents\=[].
4338
4339		get_property_components(Components) :-
4340		b_machine_has_constants_or_properties,
4341		b_get_properties_from_machine(Properties),
4342		add_additional_properties(Properties,NewProperty),
4343		bsyntaxtree:predicate_components(NewProperty,Components),!.
4344		get_property_components([]).
4345
4346		:- dynamic uses_implementable_integers/0.
4347		:- dynamic min_max_integer_value_used/2.
4348
4349
4350		tcltk_quick_describe_unsat_properties(list(FullDescr),STATUS) :-
4351		retractall(uses_implementable_integers),
4352		retractall(min_max_integer_value_used(_,_)), assertz(min_max_integer_value_used(none,none)),
4353		get_property_components(Components),
4354		(unsat_properties_conjunct_inside_component(_,_,false,_)
4355		-> STATUS='FALSE'
4356		; all_unsat_components_marked_prob_ignore
4357		-> STATUS = 'prob-ignore'
4358		; STATUS='UNKNOWN'
4359		),
4360		findall(TP, (unsat_properties_conjunct_inside_component(CompNr,P,_Status,_ReasonMsg), % find individual conjuncts
4361		% Status can be false or unknown
4362		nth1(CompNr,Components,component(FullPred,_Vars)),
4363		check_uses_implementable_integers(FullPred), % for the min-max one may need to look at the entire component !
4364		translate_bexpression_with_limit(P,TrP),
4365		get_component_enum_warning_message(CompNr,EnumWarningAbortMsg),
4366		(EnumWarningAbortMsg = '' -> Prefix = '' ; Prefix = '\n '),
4367		get_span_msg(P,'\n ',SpanMsg),
4368		ajoin([' * ',TrP,Prefix,EnumWarningAbortMsg,SpanMsg,'\n'],TP)),
4369		D1),
4370		findall([Msg1,PS|DescrVars],
4371		(get_unsat_component_description(Components,CompNr,MaxCompNr,
4372		Size,PS,DescrVars,EnumWarningAbortMsg,SpanMsg),
4373		ajoin([' * Predicate Component ',EnumWarningAbortMsg,CompNr,'/',MaxCompNr,
4374		' (with ',Size,' conjunct(s))',SpanMsg, ':'],Msg1)),
4375		UC),
4376		append(UC,UCL), % join all component descriptions
4377		(D1=[]
4378		% TO DO: adapt message for enumeration warning
4379		-> Descr = D2,
4380		(UCL=[] -> D2 = ['The properties were satisfiable']
4381		; D2 = ['No solution found for the following predicates: '|UCL]
4382		)
4383		; Descr = ['The following properties prevented finding a solution:\n'|D12],
4384		% Comment: the predicate can trigger the computation of another earlier registered predicate
4385		% Example f = {1|->2} & f: A --> B & A = 1..5; A=1..5 triggers the check for f
4386		(UCL=[] -> D2=[]
4387		; D2 = ['\nIn addition no solution was found for the following predicates: '|UCL]
4388		),
4389		append(D1,D2,D12)),
4390		findall(W,other_warning(W),Warnings),
4391		(Warnings = [] -> FullDescr=Descr ; append(Descr,['\nWARNINGS/MESSAGES:'|Warnings],FullDescr)).
4392
4393		% called by predicate_debugger:
4394		get_unsat_component_predicate(CompNr,Predicate,Vars) :-
4395		unsat_properties_component(CompNr,_FalseOrUnknown),
4396		get_property_components(Components),
4397		nth1(CompNr,Components,component(Predicate,Vars)).
4398
4399		get_unsat_component_description(Components,CompNr,MaxCompNr,Size,PS,DescrVars,EnumWarningAbortMsg,SpanMsg) :-
4400		unsat_properties_component(CompNr,_),
4401		\+ unsat_properties_conjunct_inside_component(CompNr,_,_,_), % we have not yet dealt with this component in first findall above
4402		nth1(CompNr,Components,component(Pred,Vars)),
4403		length(Components,MaxCompNr),
4404		size_of_conjunction(Pred,Size),
4405		describe_constants(Vars,DescrVars),
4406		check_uses_implementable_integers(Pred), % store information in case it does use implementable integers for later user messages
4407		(debug_mode(on) -> Lim = 1500 ; Lim = 250),
4408		translate_bexpression_with_limit(Pred,Lim,PS),
4409		get_component_enum_warning_message(CompNr,EnumWarningAbortMsg),
4410		% note: sometimes we have a conjunction with empty span info, but different conjuncts (possibly from different files):
4411		get_span_msg(Pred,'\n ',SpanMsg).
4412
4413		get_span_msg(Pred,Prefix,SpanMsg) :-
4414		(extract_span_description(Pred,SpanStr) -> ajoin([Prefix,SpanStr],SpanMsg) ; SpanMsg = '').
4415
4416		get_component_enum_warning_message(CompNr,EnumWarningAbortMsg) :-
4417		(unsat_properties_enumeration_warning(CompNr)
4418		->(unsat_properties_abort_error(CompNr)
4419		-> EnumWarningAbortMsg = '[** with Enumeration Warning and WD-ERROR **] '
4420		; EnumWarningAbortMsg = '[* with Enumeration Warning *] ')
4421		; (unsat_properties_abort_error(CompNr)
4422		-> EnumWarningAbortMsg = '[** with WD-ERROR **] '
4423		; EnumWarningAbortMsg = '')
4424		).
4425
4426		describe_constants([],R) :- !,R=[].
4427		describe_constants(Vars,['* over identifiers : '|Vars]).
4428
4429		check_uses_implementable_integers(_) :- specfile:eventb_mode,!. % cannot use implementable integers
4430		check_uses_implementable_integers(_) :- uses_implementable_integers,!. % no need to check another component
4431		check_uses_implementable_integers(Pred) :-
4432		(uses_implementable_integers(Pred)
4433		-> assertz(uses_implementable_integers),
4434		retract(min_max_integer_value_used(Min,Max)),
4435		min_max_integer_value_used(Pred,Min,Max,NewMin,NewMax),
4436		assertz(min_max_integer_value_used(NewMin,NewMax))
4437		; true).
4438
4439		other_warning(W) :- uses_implementable_integers,
4440		preferences:get_preference(minint,MININT),
4441		preferences:get_preference(maxint,MAXINT),
4442		min_max_integer_value_used(Min,Max),
4443		( (number(Min),Min<MININT ; number(Max),Max>MAXINT)
4444		-> ajoin(['\n MININT...MAXINT only set to ',MININT,'..',MAXINT,' but integers used at least from ',Min,'..',Max],W)
4445		; (MAXINT < 127 ; MININT > -128)
4446		-> ajoin(['\n MININT...MAXINT possibly too small: ',MININT,'..',MAXINT],W)).
4447		% TO DO: we could also extract explicit integer values used in the component and compare them against MININT/MAXINT
4448		other_warning(W) :- bmachine_eventb:deferred_set_equality_without_enumeration_axioms(X,_Set),
4449		translate_bexpression_with_limit(X,XS),
4450		ajoin(['\n Set not recognized as enumerated: ',XS],W).
4451		% TO DO: generate warning if MAXINT/MININT small and NAT,NAT1 or INT was used in component(s) above
4452
4453		% call if tcltk_quick_describe_unsat_properties fails:
4454		% TODO: maxint warning above
4455		generate_unsat_properties_warnings :- uses_implementable_integers,
4456		preferences:get_preference(minint,MININT),
4457		preferences:get_preference(maxint,MAXINT),
4458		min_max_integer_value_used(Min,Max),
4459		(number(Min),Min<MININT ; number(Max),Max>MAXINT),
4460		ajoin(['MININT...MAXINT only set to ',MININT,'..',MAXINT,' but integers used at least from ',Min,'..',Max],Msg),
4461		add_warning(setup_constants_unknown,Msg),
4462		fail.
4463		generate_unsat_properties_warnings :-
4464		bmachine_eventb:deferred_set_equality_without_enumeration_axioms(X,Set),
4465		translate_bexpression_with_limit(X,TX),
4466		Eq = b(equal(X,Set),pred,[]),
4467		ajoin(['Deferred SET ',TX,' was not recognized as an enumerated set, you may want to use partition instead of the equality: '],Msg),
4468		add_warning(setup_constants_unknown,Msg,Eq,X),
4469		fail.
4470		generate_unsat_properties_warnings.
4471
4472		% -------------
4473
4474		% Complete is either complete_properties or partial_properties if properties were marked as ignore
4475		b_set_up_concrete_constants(NormalisedConstantsState,Complete) :-
4476		reset_unsat_component_infos,
4477		retractall(properties_were_filtered(_)),
4478		(no_solution_found_for_constants -> true ; assertz(no_solution_found_for_constants)),
4479		% preference(allow_incomplete_partial_setup_constants,AllowSkipping),
4480		reset_component_info(true),
4481		b_machine_has_constants_or_properties,
4482		b_get_machine_constants(UnsortedConstants),
4483		!,
4484		silent_mode(SilentMode),
4485	?	(SilentMode=on -> true ; bt_start_ms_timer('SETUP_CONSTANTS')), % TO DO: store time for unsat core
4486		b_get_properties_from_machine(MProperties),
4487		(get_preference(use_ignore_pragmas,true) % filter out prob-ignore predicates here
4488		-> conjunction_to_list(MProperties,LMP), % TO DO avoid this conversion and back
4489		exclude_count(predicate_has_ignore_pragma, LMP,LMP2,Excluded), % exclude props marked as prob-ignore
4490		conjunct_predicates(LMP2,MProperties2),
4491		%format('FILTERED (~w): ',[Excluded]),translate:print_bexpr(MProperties2),nl,
4492		(Excluded=0 -> Complete=complete_properties
4493		; assertz(properties_were_filtered(Excluded)), Complete=partial_properties)
4494		; MProperties2=MProperties,
4495		Complete=complete_properties
4496		),
4497		add_additional_properties(MProperties2,Properties),
4498		project_onto_static_assertions(Properties,UnsortedConstants,PProperties,PUnsortedConstants),
4499	?	solve_properties(PProperties,PUnsortedConstants,ConstantsState),
4500	?	(SilentMode=on -> true ; bt_stop_ms_timer('SETUP_CONSTANTS')),
4501		normalise_store(ConstantsState,NormalisedConstantsState),
4502		retractall(no_solution_found_for_constants). /* ensure that b_partial_set_up_concrete_constants fails */
4503		b_set_up_concrete_constants([],complete).
4504
4505
4506		% solve already projected and filtered properties and constants, return state with solution for constants
4507		% cbc_solve_timed almost does what we want; but looks at current state; see solve_free_aux
4508		% TODO: move this to a separate module and add cdclt
4509		solve_properties(PProperties,PUnsortedConstants,ConstantsState) :-
4510		get_preference(use_solver_on_load,Solver),
4511	?	solve_properties(Solver,PProperties,PUnsortedConstants,ConstantsState).
4512
4513		solve_properties(sat,Properties,_TypedConstants,ConstantsState) :- !,
4514	?	b2sat:solve_predicate_with_satsolver_free(Properties, ConstantsState,Result,[]),
4515		Result=solution(_).
4516		solve_properties('sat-z3',Properties,_TypedConstants,ConstantsState) :- !,
4517		b2sat:solve_predicate_with_satsolver_free(Properties, ConstantsState,Result,[use_satsolver(z3)]),
4518		Result=solution(_).
4519		solve_properties(cdclt,Properties,_TypedConstants,ConstantsState) :- !,
4520		cdclt_solver:cdclt_solve_predicate(Properties,_,Result),
4521		Result=solution(ConstantsState).
4522		solve_properties(clingo,Properties,_TypedConstants,ConstantsState) :- !,
4523		get_preference(maxNrOfInitialisations,MaxNrSols),
4524		b2asp:solve_pred_with_clingo(Properties,MaxNrSols,_,Result,_Exhaustive),
4525		% TODO: check if non_exhaustive and assert max_reached ?
4526		Result=solution(ConstantsState).
4527		solve_properties(kodkod,PProperties,PUnsortedConstants,ConstantsState) :- !,
4528	?	solve_properties(prob,PProperties,PUnsortedConstants,ConstantsState). % Kodkod processing is done elswehere
4529		solve_properties(prob,PProperties,PUnsortedConstants,ConstantsState) :- !,
4530		(preferences:preference(use_static_ordering,true)
4531		-> sort_ids_by_usage(PUnsortedConstants,PProperties,Constants,no_warnings), % no_warnings as Ids could be used in operations, assertions, ...
4532		set_up_typed_localstate(Constants,_FreshVars,TypedVals,[],SortedState,positive),
4533	?	reorder_state(PUnsortedConstants,SortedState,ConstantsState)
4534		; Constants = PUnsortedConstants,
4535	?	set_up_typed_localstate(Constants,_FreshVars,TypedVals,[],ConstantsState,positive)
4536		),
4537		% now try and load saved constants from file for sub-machines when -cache is used:
4538	?	load_partial_constants(ConstantsState,PProperties,LPProperties), % Note: this can backtrack
4539		reset_component_info(true), % reset in case load_partial_constants backtracks! relevant for test 2112
4540		b_global_sets:static_symmetry_reduction_for_global_sets(ConstantsState),
4541	?	b_trace_test_components_full(LPProperties,ConstantsState,TypedVals).
4542		solve_properties(SolverName,Properties,_TypedConstants,ConstantsState) :-
4543		temporary_set_preference(z3_solve_for_animation, true,Chng),
4544		call_cleanup(smt_solvers_interface:smt_solve_predicate_free(SolverName, Properties, ConstantsState),
4545		reset_temporary_preference(z3_solve_for_animation,Chng)).
4546
4547
4548		b_trace_test_components_full(LPProperties,ConstantsState,TypedVals) :-
4549		init_wait_flags_and_push_call_stack(no_wf_available,operation_call('SETUP_CONSTANTS',[],unknown),WF),
4550	?	b_trace_test_components_wf(LPProperties,ConstantsState,TypedVals,WF),
4551		ground_wait_flags(WF), % WF is just a dummy waitflag to pass call stack info
4552		(unsat_or_unknown_component_exists -> (!,fail) ; true). % otherwise some expressions were skipped; use partial_set_up
4553
4554		:- volatile project_properties_on_identifiers/1.
4555		:- dynamic project_properties_on_identifiers/1.
4556		set_projection_on_static_assertions(ALL) :-
4557		% set interpreter in mode which projects out all constants not needed
4558		% for static assertion checking; all variables are also projected out
4559		retractall(project_properties_on_identifiers(_)),
4560		(b_get_assertions(ALL,dynamic,[]) -> true
4561		; nl,print('*** WARNING: DYNAMIC B ASSERTIONS NOT EMPTY'),nl,nl),
4562	?	b_get_assertions(ALL,static,L),
4563		(L=[] -> nl,print('*** WARNING: NO STATIC B ASSERTIONS ***'),nl,nl ; true),
4564		conjunct_predicates(L,Conj),
4565		(debug_mode(on) -> print('Static Assertion: '),translate:print_bexpr(Conj),nl ; true),
4566		bsyntaxtree:predicate_identifiers(Conj,IDs),
4567		(debug_mode(on) -> print('IDS: '), print(IDs),nl ; true),
4568		assertz(project_properties_on_identifiers(IDs)).
4569
4570		% optionally project properties onto those required for checking assertions
4571		project_onto_static_assertions(Properties,Constants,NewProperties,NewConstants) :-
4572		%% set_projection_on_static_assertions(main), %% main or all %% set by probcli if we_need_only_static_assertions
4573		project_properties_on_identifiers(ProjIDs),
4574		bsyntaxtree:project_predicate_on_identifiers(Properties,ProjIDs,NewProperties,PIDs,_),
4575		sort(PIDs,SIPDs),
4576		debug_println(9,projecting(SIPDs)),
4577		include(keep_constant(SIPDs),Constants,NewConstants),!. % Constants is a typed identifier list.
4578		project_onto_static_assertions(Properties,Constants,Properties,Constants).
4579
4580		keep_constant(SIPDs,TypedID) :- get_texpr_id(TypedID,ID),ord_member(ID,SIPDs).
4581
4582
4583
4584		/* 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 */
4585		:- use_module(specfile,[get_specification_description/2]).
4586		b_partial_set_up_concrete_constants(NormalisedConstantsState) :-
4587		assert_unsat_component_infos(Status), % Status is false or unknown
4588		no_solution_found_for_constants,
4589		(b_partial_set_up_concrete_constants2(NormalisedConstantsState,Status)
4590		-> generate_unsat_properties_warnings
4591		; generate_unsat_properties_warnings,fail).
4592
4593		b_partial_set_up_concrete_constants2(NormalisedConstantsState,Status) :-
4594		b_get_machine_constants(Constants),
4595		Constants \= [],
4596	?	(det_solution_for_constant_was_stored(Cst1) -> true), % we have found a solution for at least one constant
4597		%set_up_typed_localstate(Constants,[],ConstantsState), -> can create call_residue due to typing fd/2 values
4598		findall(bind(ID,_),(member(TID,Constants),def_get_texpr_id(TID,ID)),ConstantsState),
4599		formatsilent('SETUP_CONSTANTS not successful, but solutions were found for some constants (e.g., ~w):~n',[Cst1]),
4600		(fill_in_det_solutions(ConstantsState,FC)
4601		-> All=all, TMSG = [')']
4602		; All=some, TMSG = [', e.g., ',Cst1,')']
4603		),
4604		(preference(allow_incomplete_partial_setup_constants,true)
4605		-> true
4606		; % fill_in_det_solutions will fail if not all constants valued and
4607		% if allow_incomplete_partial_setup_constants is false
4608		get_specification_description(properties,PS),
4609		% TO DO: determine if time-out occurred or not
4610		(Status=false
4611		-> ajoin([PS,' are unsatisfiable (but ',All,' CONSTANTS valued'|TMSG],Msg),
4612		add_error(setup_constants_inconsistent,Msg)
4613		; unsat_properties_abort_error(_)
4614		-> ajoin([PS,' are unknown due to well-definedness error(s) (but ',All,' CONSTANTS valued'|TMSG],Msg),
4615		add_error(setup_constants_unknown,Msg)
4616		; unsat_component_enumeration_warning(_)
4617		-> ajoin([PS,' are unknown due to enumeration warning(s) (but ',All,' CONSTANTS valued'|TMSG],Msg),
4618		add_error(setup_constants_unknown,Msg)
4619		; all_unsat_components_marked_prob_ignore
4620		-> ajoin([PS,' are unknown due to prob-ignore pragmas (but ',All,' CONSTANTS valued'|TMSG],Msg),
4621		add_message(setup_constants_unknown,Msg)
4622		;
4623		ajoin([PS,' are unknown (but ',All,' CONSTANTS valued'|TMSG],Msg),
4624		% typical message: but some CONSTANTS valued
4625		add_error(setup_constants_unknown,Msg)
4626		),
4627		All=all % only continue if all constants valued
4628		),
4629		normalise_store(FC,NormalisedConstantsState).
4630
4631
4632		:- use_module(store,[no_value_for_variable/2]).
4633		fill_in_det_solutions([],[]).
4634		fill_in_det_solutions([bind(Var,Val)|T],[bind(Var,FVal)|FT]) :-
4635		(det_solution_for_constant(Var,Val)
4636		-> (silent_mode(on) -> true ; write(' --det--> '),print_term_summary(bind(Var,Val))),
4637		FVal=Val
4638		; %format('No (deterministic) solution was found or stored for constant: ~w~n',[Var]), % message printed by det_solution_for_constant
4639		(preference(allow_incomplete_partial_setup_constants,true)
4640		-> no_value_for_variable(FVal,Var)
4641		; format('Aborting SETUP_CONSTANTS (set preference ALLOW_INCOMPLETE_SETUP_CONSTANTS to TRUE to allow ProB to proceed without having values for all CONSTANTS)~n',[]),
4642		fail
4643		)
4644		),
4645		fill_in_det_solutions(T,FT).
4646
4647
4648
4649		/* --------------------------------- */
4650
4651		:- use_module(b_state_model_check, [b_check_valid_state/1]).
4652
4653		% note: set_up_initialisation for CBC checks does not use this predicate
4654		b_initialise_machine(ConstantsState,NormalisedInitialVarsState,FullInitialState,Path) :-
4655	?	if(b_initialise_machine2(ConstantsState,NormalisedInitialVarsState,FullInitialState,Path),
4656		true,
4657		(\+ logged_error(initialisation_fails,_,_,_), % we have already provided a more precise error message
4658		\+ abort_error_exists_in_context_state(initialisation_fails), % ditto as a state error
4659		(bmachine:b_machine_temp_predicate(TempPred)
4660		-> add_message(initialisation_fails,'INITIALISATION FAILS with provided predicate: ',TempPred,TempPred)
4661		; b_get_initialisation_from_machine(Stmt,_OType)
4662		-> add_error(initialisation_fails,'INITIALISATION FAILS','',Stmt)
4663		; add_error(initialisation_fails,'MACHINE has no INITIALISATION clause')
4664		),
4665		fail)
4666		).
4667
4668		b_initialise_machine2(ConstantsState,NormalisedInitialVarsState,FullInitialState,Path) :-
4669		/* InitialVarsState is an ouput */
4670		b_get_initialisation_from_machine(InitStatement,OType),
4671		( InitStatement=[] ->
4672		Path = [],
4673		add_message(b_initialise_machine,'Machine has no INITIALISATION statement(s)!'),
4674		NormalisedInitialVarsState = [],
4675		FullInitialState = ConstantsState
4676		; OType == classic ->
4677		Path = [path(PathInfo)],
4678		b_get_machine_variables(DeclaredVars),
4679		set_up_undefined_localstate(DeclaredVars,ConstantsState,NewInState),
4680		/* this is if the INITIALISATION has a sequential composition; to avoid error messages */
4681		get_texpr_info(InitStatement,PosInfo),
4682		init_wait_flags_with_call_stack(WF,[operation_call('INITIALISATION',[],PosInfo)]),
4683		(bmachine:b_machine_temp_predicate(_)
4684		-> InitStatement2=InitStatement /* avoid enumerating each init statement in parallel in case additional guard links them */
4685		; translate_init_statements(InitStatement,InitStatement2)
4686		),
4687		check_additional_guard(true,InitialVarsState,ConstantsState,WF),
4688	?	b_execute_statement(InitStatement2,[],NewInState,InitialVarsState,WF,PathInfo),
4689		% Warning: in Z mode (e.g. test 565) the variable skeleton may not yet be set up !
4690		sort_variable_binding(InitialVarsState,NormalisedInitialVarsState),
4691		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
4692		split_names_and_types(DeclaredVars,DeclaredNames,DeclaredTypes),
4693	?	ground_wait_flags(WF),
4694
4695		b_enumerate_values_in_store(DeclaredNames,DeclaredTypes,_,InitialVarsState,WF) %% MOVED HERE TO AVOID that target values are enumerated before initialisation effect computed
4696		; OType = eventb_operation(_ChangeSet,ParaValues,_Operation) ->
4697		prepare_eventb_initialisation(ConstantsState,InitialVarsUnNormState,FullInitialUnNormState),
4698		get_texpr_expr(InitStatement,
4699		rlevent(_Name,_Sec,_Stat,Parameters,_Grd,_Thm,_Act,_VWit,_PWit,_Unmod,_AbsEv)),
4700	?	b_execute_event('initialisation',InitStatement,Parameters,ParaValues,ConstantsState,FullInitialUnNormState,Path),
4701		normalise_store(InitialVarsUnNormState,NormalisedInitialVarsState),
4702		normalise_store(FullInitialUnNormState,FullInitialState) % a bit of redundant work here; we do the work twice and try to normalise constants again !
4703		),
4704		b_check_valid_state(FullInitialState).
4705
4706		% ensure that the variables always appear in the same order as reported by b_get_machine_variables:
4707		% 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 ??
4708		sort_variable_binding(Store,SortedStore) :- %print(sort_variable_binding(Store,SortedStore)),nl,
4709		b_get_machine_variables(Variables),
4710		sort_aux(Variables,Store,[],SortedStore).
4711		sort_aux([],S,Acc,NormRes) :- reverse(Acc,Res),
4712		normalise_store(Res,NormRes),
4713		(S=[] -> true ; add_internal_error('Unknown variable bindings: ',S)).
4714		sort_aux([TVar|T],Store,Acc,Res) :- def_get_texpr_id(TVar,ID),
4715		bselect(ID,Val,Store,Rest),
4716		sort_aux(T,Rest,[bind(ID,Val)|Acc],Res).
4717
4718		:- block bselect(?,?,-,?). % in Z mode (e.g. test 565) the variable skeleton may not yet be set up !
4719		bselect(ID,Val,[bind(ID1,Val1)|T],Rest) :- % we assume ID1 is nonvar
4720		(ID=ID1 -> Val=Val1,T=Rest
4721		; Rest = [bind(ID1,Val1)|RT],
4722		bselect(ID,Val,T,RT)).
4723
4724		prepare_eventb_initialisation(ConstantsState,InitialVarsState,FullInitialState) :-
4725		b_get_machine_variables(Variables),
4726		empty_state(Empty),
4727		set_up_typed_localstate(Variables,_,_,Empty,InitialVarsState,positive),
4728		% NormalisedInitialVarsState = InitialVarsState, % TO DO : check that b_event normalises this
4729		combine_updates(InitialVarsState,ConstantsState,FullInitialState).
4730		% put constants at end, to be compatible with b_initialise_machine2 and expand_const_and_vars order and e.g. ltsmin
4731
4732
4733
4734		reset_b_interpreter :-
4735		%reset_partial_evaluator,
4736		retractall(project_properties_on_identifiers(_)),
4737		reset_unsat_component_infos,
4738		retractall(no_solution_found_for_constants).
4739
4740		:- use_module(eventhandling,[register_event_listener/3]).
4741		:- register_event_listener(clear_specification,reset_b_interpreter,
4742		'Reset B-Interpreter Memo Table & Unsat Components.').