1		% (c) 2009-2024 Lehrstuhl fuer Softwaretechnik und Programmiersprachen,
2		% Heinrich Heine Universitaet Duesseldorf
3		% This software is licenced under EPL 1.0 (http://www.eclipse.org/org/documents/epl-v10.html)
4
5		:- module(state_space,
6		[get_state_space_stats/3, get_state_space_stats/4,
7		gen_new_state_id/1,
8		history/1, forward_history/1,
9		get_action_trace/1, % old trace/1
10		get_action_trace_with_limit/2,
11		get_action_term_trace/1,
12		op_trace_ids/1, add_to_op_trace_ids/1, remove_from_op_trace_ids/1, reset_op_trace_ids/0,
13		get_state_id_trace/1,
14		current_state_id/1, current_expression/2,
15		set_current_state_id/1,
16		current_options/1, set_current_options/1,
17		get_current_predecessor_state_id/1,
18
19		add_id_at_front/1, add_id_at_end/1,
20		add_id_random/1, /* from state_space_open_nodes_c */
21		add_id_with_weight/2, add_id_to_process/3,
22		pop_id_from_front/1, pop_id_from_end/1, pop_id_oldest/1,
23		retract_open_node/1, open_ids_empty/0,
24		top_front_id/1, top_front_weight/1,
25
26		visited_expression/3, visited_expression/2, visited_expression_id/1,
27		find_hashed_packed_visited_expression/3,
28		retract_visited_expression/2,
29		not_all_transitions_added/1,
30		not_invariant_checked/1, set_invariant_checked/1,
31		invariant_not_yet_checked/1, invariant_still_to_be_checked/1,
32		not_interesting/1, % nodes ignored because they do not satisfy a user-provided scope predicate
33		mark_as_not_interesting/1,
34		max_reached_for_node/1,
35		max_reached_or_timeout_for_node/1,
36		use_no_timeout/1, time_out_for_node/1, time_out_for_node/3,
37		hash_to_id/2,id_to_marker/2, hash_to_nauty_id/2,
38		register_back_edge/2, try_compute_depth_of_state_id/2,
39		invariant_violated/1, time_out_for_invariant/1, time_out_for_assertions/1,
40		set_invariant_violated/1,
41
42		state_error_exists/0, state_error/3, store_state_error/3,
43		set_context_state/1, set_context_state/2,
44		update_context_state/1, clear_context_state/0, get_current_context_state/1,
45		store_error_for_context_state/2,
46		copy_current_errors_to_state/2,
47		store_abort_error_for_context_state_if_possible/4,
48		abort_error_exists_in_context_state/1,
49
50		transition/3,transition/4, any_transition/3,
51		store_transition/4,
52		deadlocked_state/1, % no outgoing edge
53		is_initial_state_id/1, is_concrete_constants_state_id/1,
54		multiple_concrete_constants_exist/0,
55		get_constants_state_for_id/2, get_constants_state_id_for_id/2,
56		try_get_unique_constants_state/1,
57		get_constants_id_for_state_id/2,
58		get_variables_state_for_id/2,
59		out_degree/2,
60		operation_not_yet_covered/1, operation_name_not_yet_covered/1,
61		get_operation_name_coverage_infos/4,
62		mark_operation_as_covered/1,
63		initialise_operation_not_yet_covered/0,
64
65		transition_info/2, store_transition_infos/2,
66		keep_transition_info/1,
67		compute_transitions_if_necessary/1,
68
69		state_space_initialise/0, state_space_initialise_with_stats/0,
70		state_space_reset/0,
71		state_space_add/2, state_space_packed_add/2,
72		delete_node/1,
73
74		current_state_corresponds_to_initialised_b_machine/0,
75		current_state_corresponds_to_fully_setup_b_machine/0,
76		current_state_corresponds_to_setup_constants_b_machine/0,
77		visited_state_corresponds_to_initialised_b_machine/1,
78		visited_state_corresponds_to_setup_constants_b_machine/1,
79
80		specialized_inv/2, %reuse_operation/4,
81		assert_max_reached_for_node/1, assert_time_out_for_node/3,
82		assert_time_out_for_invariant/1, assert_time_out_for_assertions/1,
83
84		set_max_nr_of_new_impl_trans_nodes/1,
85		get_max_nr_of_new_impl_trans_nodes/1,
86		impl_trans_term/3, impl_trans_term_all/2,
87		impl_trans_id/4, impl_trans_not_complete/1,
88		compute_transitions_if_necessary_saved/1,
89		max_nr_of_new_nodes_limit_not_reached/0,
90
91		find_trace_to_initial_state/2, find_initialised_states/1,
92
93		tcltk_save_state_space/1, tcltk_load_state/1,
94		compute_full_state_space_hash/1,
95
96		execute_id_trace_from_current/3,
97		set_trace_by_transition_ids/1, try_set_trace_by_transition_ids/1,
98		extend_trace_by_transition_ids/1,
99		extract_term_trace_from_transition_ids/2,
100
101		add_counterexample_node/1, add_counterexample_op/1,
102		reset_counterexample/0, set_counterexample_by_transition_ids/1,
103		counterexample_node/1, counterexample_op/1 % specific predicates to register counter examples
104		]).
105
106		:- use_module(library(lists)).
107
108		:- use_module(self_check).
109		:- use_module(error_manager).
110		:- use_module(gensym).
111		:- use_module(preferences).
112		:- use_module(tools).
113		%:- use_module(state_space_exploration_modes,[compute_hash/3]).
114
115		:- use_module(extension('counter/counter'),
116		[counter_init/0, new_counter/1, get_counter/2, inc_counter/1, inc_counter/2, inc_counter_by/2, reset_counter/1, set_counter/2]).
117
118		:- use_module(module_information).
119		:- module_info(group,state_space).
120		:- module_info(description,'This module keeps track of the visited states by the animator/model checker.').
121
122		% ----------------------------------
123
124		:- load_files(library(system), [when(compile_time), imports([environ/2])]).
125		:- if((environ(prob_myheap,false) ; \+ predicate_property(load_foreign_resource(_), _))).
126		:- use_module(state_space_open_nodes). %% comment in to use only Prolog datastructures
127		:- else.
128		:- use_module(state_space_open_nodes_c). %% comment in to use C++ multimap queue; can make use of HEURISTIC_FUNCTION
129		:- endif.
130
131		% ----------------------------------
132
133		get_state_space_stats(NrNodes,NrTransitions,ProcessedNodes) :-
134		get_counter(states,N), NrNodes is N+1,
135		get_counter(transitions,NrTransitions),
136		get_counter(processed_nodes,ProcessedNodes).
137
138		get_state_space_stats(NrNodes,NrTransitions,ProcessedNodes,IgnoredNodes) :-
139		get_state_space_stats(NrNodes,NrTransitions,ProcessedNodes),
140		get_counter(not_interesting_nodes,IgnoredNodes).
141
142		gen_new_state_id(Nr) :-
143		inc_counter(states,N1), Nr is N1-1. % only one C call
144		%get_counter(states,Nr), inc_counter(states).
145		reset_state_counter :- reset_counter(states).
146		reset_state_counter(Nr) :- set_counter(states,Nr).
147
148		get_state_id_trace(StateIds) :-
149		history(History),
150		current_state_id(CurID),
151		reverse([CurID|History],StateIds).
152
153		get_current_predecessor_state_id(PriorID) :-
154		history([PriorID|_]).
155
156		:- dynamic history/1.
157		history([]).
158
159
160		:- dynamic forward_history/1.
161
162		:- dynamic current_state_id/1.
163		current_state_id(root).
164		/* INITIAL STATE, third arg: clp(fd) constraints as generated
165		by fd_copy_term */
166
167		current_expression(ID,State) :- current_state_id(ID),
168		visited_expression(ID,State).
169		current_packed_expression(ID,State) :- current_state_id(ID),
170		packed_visited_expression(ID,State).
171
172		:- use_module(specfile,[state_corresponds_to_initialised_b_machine/1,
173		state_corresponds_to_fully_setup_b_machine/1,
174		state_corresponds_to_set_up_constants/1]).
175		current_state_corresponds_to_initialised_b_machine :-
176		current_packed_expression(_,PS), unpack_state_top_level(PS,TLState),
177		state_corresponds_to_initialised_b_machine(TLState).
178		visited_state_corresponds_to_initialised_b_machine(ID) :-
179		packed_visited_expression(ID,PS), unpack_state_top_level(PS,TLState),
180		state_corresponds_to_initialised_b_machine(TLState).
181
182		current_state_corresponds_to_fully_setup_b_machine :-
183		current_packed_expression(_,PS), unpack_state_top_level(PS,TLState),
184		state_corresponds_to_fully_setup_b_machine(TLState).
185
186		current_state_corresponds_to_setup_constants_b_machine :-
187		current_packed_expression(_,PS), unpack_state_top_level(PS,TLState),
188		state_corresponds_to_set_up_constants(TLState).
189
190		visited_state_corresponds_to_setup_constants_b_machine(ID) :-
191		packed_visited_expression(ID,PS), unpack_state_top_level(PS,TLState),
192		state_corresponds_to_set_up_constants(TLState).
193
194		:- dynamic current_options/1.
195		current_options([]).
196
197		set_current_options(Options) :-
198		retractall( current_options(_) ),
199		assertz( current_options(Options) ).
200
201		:- dynamic packed_visited_expression/2.
202		%packed_visited_expression(v_0,true).
203
204		:- use_module(state_packing).
205
206		retract_visited_expression(ID,State) :- retract(packed_visited_expression(ID,PState)),
207		unpack_state(PState,State).
208
209		retractall_visited_expression(ID) :- retractall(packed_visited_expression(ID,_)).
210
211		state_space_packed_add(Id,PackedTerm) :- assertz(packed_visited_expression(Id,PackedTerm)).
212
213		state_space_add(Id,Term) :-
214		(pack_state(Term,PackedTerm) -> assertz(packed_visited_expression(Id,PackedTerm))
215		; add_internal_error('State packing failed: ',pack_state(Term,_)),
216		assertz(packed_visited_expression(Id,Term))).
217
218		% deprecated:
219		visited_expression(ID,State,true) :- visited_expression(ID,State).
220		% not call(CurBody); for the moment we always have true as last argument
221
222		visited_expression(A,B) :- packed_visited_expression(A,PB),
223		(unpack_state(PB,R) -> B=R ; add_internal_error('Unpacking state failed: ',unpack_state(PB,R)),R=A).
224
225		%visited_expression_id(A) :- packed_visited_expression(A,_). % avoid unpacking state
226		% even better: not to look up fact at all to avoid constructing state term, this is done below:
227		:- use_module(library(between),[between/3]).
228		visited_expression_id(ID) :- number(ID),!, ID>=0, get_counter(states,N), ID<N.
229		visited_expression_id(ID) :- ID==root,!.
230		visited_expression_id(root).
231		visited_expression_id(Nr) :- Nr \== root, get_counter(states,N), N1 is N-1, between(0,N1,Nr).
232
233		% given a hash and a packed state: find ID (fail if does not exist)
234		find_hashed_packed_visited_expression(Hash,PackedState,ID) :-
235		hash_to_id(Hash,ID),
236		(packed_visited_expression(ID,PackedState)
237		-> true /* warning: may instantiate State if not ground */
238		; print(hash_collision(Hash,ID)),nl,fail
239		).
240
241
242		:- dynamic not_invariant_checked/1.
243		set_invariant_checked(ID) :- %print(inv_checked(ID)),nl,
244		retract(not_invariant_checked(ID)).
245
246		invariant_not_yet_checked(ID) :-
247		not_all_transitions_added(ID) ; /* assumption: if not all transitions added then we haven't checked invariant yet */
248		not_invariant_checked(ID) ;
249		not_interesting(ID). % assumption: if a node is marked as not interesting it will not be examined
250
251		% difference with invariant_not_yet_checked: not interesting nodes not reported and cannot be backtracked
252		invariant_still_to_be_checked(ID) :-
253		(not_all_transitions_added(ID) -> true ; not_invariant_checked(ID) -> true).
254
255		:- dynamic not_interesting/1.
256		%not_interesting(v_0).
257
258		:- dynamic max_reached_for_node/1.
259		/* true if not all outgoing transistions were computed due to the limit
260		on the number of operations/initialisations computed */
261		:- dynamic time_out_for_node/3, use_no_timeout/1, time_out_for_invariant/1, time_out_for_assertions/1.
262
263		time_out_for_node(ID) :- (var(ID) -> visited_expression_id(ID) ; true),
264		(time_out_for_node(ID,_,_) -> true ; fail).
265
266		:- dynamic transition/4.
267		%transition(v_0,a,1,v_1).
268
269		store_transition(Org,Action,Dest,Id) :-
270		%get_counter(transitions,Id), inc_counter(transitions),
271		inc_counter(transitions,Id1), Id is Id1-1, % only one C call
272		assertz(transition(Org,Action,Id,Dest)).
273
274		deadlocked_state(Origin) :- \+ any_transition(Origin,_,_).
275
276		is_concrete_constants_state_id(ID) :-
277		transition(root,_,ID),
278		packed_visited_expression(ID,concrete_constants(_)).
279
280		% check if we have multiple constant setups
281		multiple_concrete_constants_exist :-
282		is_concrete_constants_state_id(ID),
283		is_concrete_constants_state_id(ID2), ID2 \= ID,!.
284
285
286		is_initial_state_id(InitialStateID) :-
287		transition(root,_,State),
288		packed_visited_expression(State,P),
289		(P = concrete_constants(_) % also covers '$partial_setup_constants'
290		-> state_space:transition(State,_,InitialStateID)
291		; InitialStateID=State).
292
293		% get the constants for a state (if there are constants)
294		get_constants_state_for_id(ID,ConstantsState) :-
295		visited_expression(ID,State), % TO DO: use packed_visited_expression for performance
296		get_constants_state_aux(State,ConstantsState).
297		get_constants_state_aux(concrete_constants(ConstantsState),ConstantsState).
298		get_constants_state_aux(const_and_vars(ID,_),State) :- get_constants_state_for_id(ID,State).
299
300		% get the staet id for associated constants state for a state (if there are constants)
301		get_constants_state_id_for_id(ID,CstID) :-
302		visited_expression(ID,State), % TO DO: use packed_visited_expression for performance
303		get_constants_id_for_id_aux(State,ID,CstID).
304		get_constants_id_for_id_aux(concrete_constants(_),ID,ID).
305		get_constants_id_for_id_aux(const_and_vars(ID,_),_,ID).
306
307		get_variables_state_for_id(ID,VarState) :-
308		visited_expression(ID,State),
309		get_vars_aux(State,VarState).
310		%get_vars_aux(concrete_constants(ConstantsState),[]).
311		get_vars_aux(const_and_vars(_,Vars),State) :- !, State=Vars.
312		get_vars_aux([],[]).
313		get_vars_aux([H|T],[H|T]).
314
315		% check if there is a unique constants state:
316		try_get_unique_constants_state(ConstantsState) :-
317		transition(root,_,_TransID,DestID),
318		\+ (transition(root,_,_,DestID2), DestID2 \= DestID), % no other transition exists
319		\+ max_reached_or_timeout_for_node(root),
320		DestID \= root, % DestID=root should never happen
321		get_constants_state_for_id(DestID,ConstantsState).
322
323		% returns id of constants state for a state (if it exists)
324		get_constants_id_for_state_id(ID,ConstID) :-
325		packed_visited_expression(ID,'$cst_vars'(ConstID,_)).
326
327		any_transition(Origin,TransID,Destination) :- transition(Origin,_,TransID,Destination).
328
329		transition(Origin,Action,Destination) :- transition(Origin,Action,_TransID,Destination).
330
331		:- dynamic transition_info/2.
332		store_transition_infos([],_TransId).
333		store_transition_infos([Info|Irest],TransId) :-
334		store_transition_info(Info,TransId),
335		store_transition_infos(Irest,TransId).
336		store_transition_info(Info,TransId) :- %print(info(Info,TransId)),nl,
337		(keep_transition_info(Info)
338		-> assertz(transition_info(TransId,Info))
339		; true).
340
341		% Do not store path info by default
342		keep_transition_info(path(_)) :- !,fail.
343		keep_transition_info(eventtrace(_)) :- !,preference(eventtrace,true).
344		keep_transition_info(event(_)) :- !,preference(store_event_transinfo,true).
345		keep_transition_info(_). % store everything else
346
347		reset_transition_store :-
348		retractall(transition(_,_,_,_)),
349		retractall(transition_info(_,_)),
350		reset_counter(transitions),
351		reset_counterexample.
352
353		/*
354		Version with packing of transitions:
355		store_transition(Org,Action,Dest,Id) :-
356		retract(transition_counter(Id)),
357		NewId is Id+1,
358		assertz(transition_counter(NewId)),
359		Action =.. [ActionName|Parameters],
360		pack_values(Parameters,PackedParameters),
361		assertz(packed_transition(Org,ActionName,PackedParameters,Id,Dest)).
362
363		transition(Origin,Action,TransID,Destination) :- nonvar(Action),!,
364		Action =.. [ActionName|Parameters],
365		packed_transition(Origin,ActionName,PackedParameters,TransID,Destination),
366		unpack_values(PackedParameters,Parameters).
367		transition(Origin,Action,TransID,Destination) :-
368		packed_transition(Origin,ActionName,PackedParameters,TransID,Destination),
369		unpack_values(PackedParameters,Parameters),
370		Action =.. [ActionName|Parameters].
371		any_transition(Origin,TransID,Destination) :- packed_transition(Origin,_,_,TransID,Destination).
372		*/
373
374		% compute out-degree of a node
375		out_degree(ID,OutDegree) :- findall(0, transition(ID,_,_,_), L), length(L,OutDegree).
376
377		operation_name_not_yet_covered(OpName) :- operation_not_yet_covered(OpName).
378
379
380		get_operation_name_coverage_infos(PossibleNr,FeasibleNr,UncovNr,UncoveredList) :-
381		findall(ON, specfile:get_possible_event(ON), Possible), length(Possible,PossibleNr),
382		findall(OF, specfile:get_feasible_event(OF), Feasible), length(Feasible,FeasibleNr),
383		findall(OpName, state_space: operation_name_not_yet_covered(OpName), UncoveredList),
384		length(UncoveredList,UncovNr).
385
386
387		:- dynamic operation_not_yet_covered/1.
388		%operation_not_yet_covered(b).
389
390		:- use_module(probsrc(debug),[formatsilent/2]).
391		mark_operation_as_covered(OpName) :-
392		(retract(operation_not_yet_covered(OpName))
393		-> (preferences:get_preference(provide_trace_information,true)
394		-> print(cover(OpName)),nl ; true),
395		(operation_not_yet_covered(_) -> true ; formatsilent('~nALL OPERATIONS COVERED~n',[]))
396		; true
397		).
398
399
400		:- use_module(bmachine,[b_top_level_operation/1]).
401		:- use_module(debug,[debug_println/1]).
402		:- use_module(probcspsrc(haskell_csp),[channel/2]).
403		initialise_operation_not_yet_covered :- retractall(operation_not_yet_covered(_)),
404		b_or_z_mode,
405	?	b_top_level_operation(Name),
406		% b_get_machine_operation(Name,_,Par,_), length(Par,Arity), functor(Op,Name,Arity),
407		% Note: no '-->' added
408		assertz(operation_not_yet_covered(Name)),
409		debug_println(operation_not_yet_covered(Name)),
410		fail.
411		/* Missing: treat operations with return values */
412		initialise_operation_not_yet_covered :- csp_mode, \+ csp_with_bz_mode,
413		channel(Name,_),
414		assertz(operation_not_yet_covered(Name)),
415		debug_println(operation_not_yet_covered(Name)),
416		fail.
417		initialise_operation_not_yet_covered.
418
419		state_error_exists :- state_error(_,_,_),!.
420		:- dynamic state_error/3.
421
422		%state_error([],invariant_violated).
423
424		reset_next_state_error_id_counter :- reset_counter(next_state_error_id).
425		:- use_module(tools_printing, [print_error/1, format_error_with_nl/2]).
426		:- use_module(error_manager,[print_error_span/1]).
427		store_state_error(State,Error,Id) :- state_error(State,Id,Error),!. % do not store identical error twice
428		store_state_error(State,Error,Id) :-
429		%retract( next_state_error_id(Id) ),
430		inc_counter(next_state_error_id,Id),
431		% tools_printing:print_term_summary(Error),nl, tools_printing:nested_print_term(Error),nl,
432		assertz( state_error(State,Id,Error) ).
433		store_error_for_context_state(Error,Id) :-
434		( context_state(State,Errs) ->
435		(Errs<25
436		-> store_state_error(State,Error,Id), E1 is Errs+1,
437		%assertz(context_state(State,E1))
438		set_context_number_of_errors(E1)
439		; store_state_error(State,max_state_errors_reached(25),Id)
440		)
441		;
442		add_internal_error('No known context when calling store_error_for_context_state: ',store_error_for_context_state(Error,Id)),
443		fail).
444
445		% check if we already have a certain type of error in the current context state
446		abort_error_exists_in_context_state(ErrType) :- get_current_context_state(State),
447		Error = abort_error(ErrType,_Msg,_Term,_Pos),
448		state_error(State,_Id,Error).
449
450		% copy current errors from error_manager to state errors
451		copy_current_errors_to_state(StateID,Context) :-
452		% error_manager:logged_error(Source,ErrMsg,_Context,Span), % will not retract
453		error_manager:get_error_with_span(Source,ErrMsg,Span), % will retract
454		store_state_error(StateID,abort_error(Source,ErrMsg,'',span_context(Span,Context)),SID),
455		% TO DO: use other error class
456		debug_println(stored(Source,SID,_Context,ErrMsg)),
457		fail.
458		copy_current_errors_to_state(_,_).
459
460		store_abort_error_for_context_state_if_possible(ErrType,Msg,Term,Span) :-
461		%print(store(Msg,Term,Span)),nl,
462		( get_current_context_state(State) ->
463		error_manager:get_error_context(Context),
464		(abort_error_for_same_location_exists(State,Id1,ErrType,Msg,Span),
465		abort_error_for_same_location_exists(State,Id2,ErrType,Msg,Span),
466		Id2>Id1
467		-> /* two errors of same type, for same state and same source location exists */
468		/* TO DO: maybe merge state errors */
469		simplify_span(Span,Span1),
470		compress_span(Span1,Span2),
471		store_state_error(State,abort_error(ErrType,'Further identical errors occurred (not stored !)',Term,span_context(Span2,Context)),_)
472		;
473		format_error_with_nl('! An error occurred in state ~w: ~w !',[State,ErrType]),
474		% usual errors: precondition_error, while_invariant_violation, while_variant_error,
475		% assert_error, well_definedness_error, card_overflow_error
476		print_error(Msg),
477		print_error_term(Term,Span),
478		% print_error(context_state_id(State)), % printed by print_error_context
479		print_error_context,
480		(debug_mode(on),visited_expression(State,S) -> translate:translate_bstate(S,O),print_error(O) ; true),
481		compress_span(Span,Span2),
482		print_error_span(Span2),
483		store_state_error(State,abort_error(ErrType,Msg,Term,span_context(Span2,Context)),_)
484		),
485		(add_new_event_in_error_scope(abort_error(ErrType)) -> true ; true), % should we use well_definedness_error?
486		assert_real_error_occurred(abort_error) % Note that in this case the error manager list of errors maybe empty even though real_error_occured is true. (see ProB2 kernel test de.prob.cli.integration.rules.RulesMachineTest > testReuseStateSpace)
487		; % no current context_state exists:
488		compress_span(Span,Span2),
489		add_error(ErrType,Msg,Term,Span2)
490		).
491
492
493		:- use_module(bsyntaxtree, [find_identifier_uses/3]).
494		compress_span(span_context(Span,C),span_context(CS,C)) :- !,
495		compress_span(Span,CS).
496		compress_span(pos_context(Span1,C,Span2),pos_context(CS1,C,CS2)) :- !,
497		compress_span(Span1,CS1),
498		compress_span(Span2,CS2).
499		compress_span(span_predicate(Pred,LS,S),Res) :- find_identifier_uses(Pred,[],Ids),
500		sort(Ids,SIds),
501		filter_state(LS,SIds,FLS),
502		filter_state(S,SIds,FS), % TODO: do we need to store the global state? we can reconstruct it ?
503		% format('Compressed span_predicate (~w)~n',[Ids]),
504		!,
505		Res = span_predicate(Pred,FLS,FS).
506		compress_span(S,S).
507		% avoid storing large useless values
508		% TO DO: probably we should stop storing spans when a certain threshold of number of errors is reached
509
510
511		:- use_module(library(ordsets),[ord_member/2]).
512		filter_state([],_,[]).
513		filter_state([bind(ID,L)|T],Vars,Res) :-
514		(ord_member(ID,Vars) -> Res = [bind(ID,L)|RT] ; Res=RT),
515		filter_state(T,Vars,RT).
516
517
518		:- use_module(translate, [translate_error_term/3]).
519		print_error_term(T,S) :- (var(T);var(S)),!,
520		print_error('### VARIABLE error term or span:'), print_error(print_error_term(T,S)).
521		print_error_term(Term,Span) :- translate_error_term(Term,Span,S),
522		(S='' -> true ; print_error(S)).
523
524		abort_error_for_same_location_exists(State,Id,ErrType,Msg,Span) :-
525		state_error(State,Id,abort_error(ErrType,Msg,_Term2,span_context(Span2,_Ctxt2))),
526		same_span_location(Span2,Span).
527		% should be moved to error_manager ?
528		same_span_location(span_context(Span1,C),span_context(Span2,C)) :- !, same_span_location(Span1,Span2).
529		same_span_location(pos_context(Span1,C,_),pos_context(Span2,C,_)) :- !,
530		same_span_location(Span1,Span2). % should we check second span?
531		same_span_location(span_predicate(Pred1,_,_),span_predicate(Pred2,_,_)) :- !,Pred1=Pred2.
532		same_span_location(X,X).
533
534		:- dynamic saved_nested_context_state/2.
535		save_nested_context_state(_S) :-
536		bb_get(state_space_context_state,ID),
537		bb_get(state_space_context_errors,Errs),!,
538		%print(saving_context_state(_S,ID,Errs)),nl,
539		asserta(saved_nested_context_state(ID,Errs)).
540		save_nested_context_state(_).
541
542		% actually pops context state
543		clear_context_state :-
544		retract(saved_nested_context_state(ID,Errs)),!, %print(restoring_nested(ID,Errs)),nl,
545		bb_put(state_space_context_state,ID),
546		bb_put(state_space_context_errors,Errs).
547		clear_context_state :-
548		(bb_delete(state_space_context_state,_) -> true ; true).
549		%(retract(context_state(_,_)) -> true ; true). % retractall seems to be slowing down with use
550
551		% Note: Each Prolog module maintains its own blackboard for bb_get/bb_put
552		context_state(ID,Errs) :-
553		bb_get(state_space_context_state,ID), bb_get(state_space_context_errors,Errs).
554
555		% sets a new context state; pushing the previous one if necessary
556		set_context_state(State) :- %print(set_id(State)),nl,
557		save_nested_context_state(State),
558		bb_put(state_space_context_state,State),
559		bb_put(state_space_context_errors,0).
560
561		set_context_state(State,_Context) :- % Context can be used for debugging later
562		set_context_state(State).
563
564		% update current context state, without storing nested states
565		update_context_state(State) :-
566		bb_put(state_space_context_state,State),
567		bb_put(state_space_context_errors,0).
568
569		get_current_context_state(ID) :- bb_get(state_space_context_state,ID).
570		%get_current_context_state(ID) :- context_state(ID,_).
571
572		set_context_number_of_errors(Errs) :- bb_put(state_space_context_errors,Errs).
573
574		retractall_invariant_violated(State) :-
575		retractall(state_error(State,_,invariant_violated)).
576		invariant_violated(State) :-
577		state_error(State,_,invariant_violated).
578		set_invariant_violated(State) :-
579		( invariant_violated(State) -> true
580		; time_out_for_invariant(ID) -> print('Timeout for node: '), print(ID),nl,
581		print('Not setting invariant violation status'),nl
582		; store_state_error(State,invariant_violated,_)
583		).
584
585		%:- set_invariant_violated([]). % why is this ??
586
587
588		:- dynamic hash_to_id/2.
589		:- dynamic id_to_marker/2.
590		:- dynamic id_back_edge/3. % optional facts to keep track where a state was constructed from
591
592		:- dynamic hash_to_nauty_id/2. % used in nauty mode to map nauty id's to hash values
593
594		:- dynamic specialized_inv/2. /* stores whether for a node a specialized invariant
595		version could be computed */
596
597		% :- dynamic reuse_operation/4. /* when for a state and given operation name we can reuse the operation computed for another state */
598		% used to be used for OPERATION_REUSE TRUE
599
600		:- use_module(hashing).
601		state_space_startup :- % call once at startup to ensure all counters exist
602		counter_init,
603		new_counter(states), new_counter(processed_nodes), new_counter(transitions),
604		new_counter(next_state_error_id),
605		new_counter(not_interesting_nodes),
606		reset_open_ids. % also calls myheap init
607		state_space_initialise :- counter_init, reset_gennum, reset_gensym,
608		new_counter(states), new_counter(processed_nodes), new_counter(transitions),
609		new_counter(next_state_error_id), new_counter(not_interesting_nodes),
610		reset_state_counter, reset_processed_nodes_counter, reset_next_state_error_id_counter,
611		retractall_visited_expression(_),
612		reset_open_ids,
613		reset_stored_values, % state_packing
614		retractall(not_invariant_checked(_)),
615		reset_not_interesting,
616		retractall(max_reached_for_node(_)),
617		retractall(time_out_for_node(_,_,_)),
618		retractall(time_out_for_invariant(_)),
619		retractall(time_out_for_assertions(_)),
620		retractall(use_no_timeout(_)),
621		retractall(state_error(_,_,_)),
622		clear_context_state,
623		reset_transition_store,
624		retractall(operation_not_yet_covered(_)),
625		retractall(hash_to_id(_,_)),
626		retractall(id_back_edge(_,_,_)),
627		retractall(hash_to_nauty_id(_,_)),
628		retractall(id_to_marker(_,_)),
629		retractall(specialized_inv(_,_)),
630		%retractall(reuse_operation(_,_,_,_)),
631		state_space_add(root,root),
632		add_id_at_front(root),
633		my_term_hash(root,RootHash),
634		assertz(hash_to_id(RootHash,root)),
635		%assertz(not_invariant_checked(root)),
636		state_space_reset.
637
638		:- use_module(eventhandling,[register_event_listener/3]).
639		:- register_event_listener(startup_prob,state_space_startup,
640		'Initialise Statespace Counters.').
641		:- register_event_listener(reset_specification,state_space_initialise,
642		'Reset Statespace.').
643		:- register_event_listener(change_of_animation_mode,state_space_initialise,
644		'Reset Statespace.').
645		:- register_event_listener(specification_initialised,initialise_operation_not_yet_covered,
646		'Init coverage info.').
647		:- register_event_listener(reset_prob,state_space_initialise,
648		'Reset Statespace.').
649
650		/* A version of reset which checks how much memory is used by each fact */
651		/* state_space:init_with_stats */
652		state_space_initialise_with_stats :-
653		reset_gennum, reset_gensym, reset_state_counter, reset_processed_nodes_counter,
654		reset_next_state_error_id_counter,
655		retract_open_ids_with_statistics,
656		retract_with_statistics(state_space,[packed_visited_expression(_,_),
657		not_invariant_checked(_),
658		not_interesting(_),
659		max_reached_for_node(_),
660		time_out_for_node(_,_,_),
661		time_out_for_invariant(_),
662		time_out_for_assertions(_),
663		use_no_timeout(_),
664		state_error(_,_,_),
665		transition(_,_,_,_),
666		transition_info(_,_),
667		operation_not_yet_covered(_),
668		hash_to_id(_,_),
669		hash_to_nauty_id(_,_),
670		id_to_marker(_,_),
671		specialized_inv(_,_),
672		%reuse_operation(_,_,_,_),
673		history(_), forward_history(_), op_trace_ids(_)]),
674		reset_not_interesting,
675		retract_stored_values_with_statistics,
676		clear_context_state,
677		reset_transition_store,
678		state_space_add(root,root),
679		add_id_at_front(root),
680		%assertz(not_invariant_checked(root)),
681		state_space_reset,
682		initialise_operation_not_yet_covered.
683
684
685
686		:- dynamic op_trace_ids/1.
687		reset_trace :- retractall(op_trace_ids(_)), assertz(op_trace_ids([])).
688		get_action_trace(T) :- trace(T).
689		get_action_term_trace(PT) :- get_action_trace_with_limit(0,T), project_on_action_term(T,PT).
690		trace(Trace) :- get_action_trace_with_limit(500,Trace).
691		get_action_trace_with_limit(Limit,Trace) :-
692		op_trace_ids(IDT), reverse(IDT,RIDT),
693		extract_trace_from_transition_ids(RIDT,root,Limit,[],Trace).
694
695		reset_op_trace_ids :- retractall(op_trace_ids(_)), assertz(op_trace_ids([])).
696		add_to_op_trace_ids(OpID) :- retract(op_trace_ids(OpIDS)), assertz(op_trace_ids([OpID|OpIDS])).
697		remove_from_op_trace_ids(OpID) :- retract(op_trace_ids(OpIDS)),
698		(OpIDS = [R|Rest]
699		-> assertz(op_trace_ids(Rest)), OpID = R
700		; assertz(op_trace_ids(OpIDS)), fail).
701
702		% translate a list of transition ids (from root) into a list of operation terms
703		extract_term_trace_from_transition_ids(TransIDListFromRoot,Trace) :-
704		extract_trace_from_transition_ids(TransIDListFromRoot,root,0,[],ActionTrace),
705		reverse_and_project_on_action_term(ActionTrace,[],Trace).
706
707		reverse_and_project_on_action_term([],A,A).
708		reverse_and_project_on_action_term([action(_,Term)|T],Acc,Res) :- !,
709		reverse_and_project_on_action_term(T,[Term|Acc],Res).
710		reverse_and_project_on_action_term([H|T],Acc,Res) :-
711		add_error(reverse_and_project_on_action_term,'Illegal action: ',H),
712		reverse_and_project_on_action_term(T,[H|Acc],Res).
713
714		project_on_action_term([],[]).
715		project_on_action_term([action(_,Term)|T],Res) :- !, Res=[Term|TR],
716		project_on_action_term(T,TR).
717		project_on_action_term([H|T],Res) :-
718		add_error(project_on_action_term,'Illegal action: ',H),
719		project_on_action_term(T,Res).
720
721		extract_trace_from_transition_ids([],_CurrentState,_,Trace,Trace).
722		extract_trace_from_transition_ids([TransId|Rest],CurrentState,Limit,AccTrace,Trace) :-
723		compute_op_string(TransId,CurrentState,Limit,OpTerm,OpString,DestState),!,
724		extract_trace_from_transition_ids(Rest,DestState,Limit,
725		[action(OpString,OpTerm)|AccTrace],Trace).
726		extract_trace_from_transition_ids([TransId|_],CurrentState,_,_,_Trace) :-
727		add_error(state_space,'Could not execute transition id: ', TransId:from(CurrentState)),fail.
728
729		:- use_module(translate,[translate_event_with_src_and_target_id/5]).
730		compute_op_string(jump(TO),_CurID,_,Term,String,DestID) :- !, Term=jump,String=jump,DestID=TO.
731		compute_op_string(TransId,CurID,Limit,Term,String,DestID) :- transition(CurID,Term,TransId,DestID),
732		translate_event_with_src_and_target_id(Term,CurID,DestID,Limit,String).
733
734		% reset history and forward history, but not state-space itself
735		state_space_reset :-
736		reset_trace,
737		retractall(history(_)),
738		retractall(forward_history(_)),
739		retractall(current_state_id(_)),
740		retractall(current_options(_)),
741		assertz(history([])),
742		assertz(current_state_id(root)).
743
744		reset_not_interesting :- retractall(not_interesting(_)), reset_counter(not_interesting_nodes).
745
746		mark_as_not_interesting(ID) :- assertz(not_interesting(ID)), inc_counter(not_interesting_nodes).
747
748		set_current_state_id(ID) :- (retract(current_state_id(_)) -> true ; true),
749		assertz(current_state_id(ID)).
750
751		state_space_clean_all :-
752		retractall(state_space_version_in_file(_)),
753		retractall_visited_expression(_),
754		reset_open_ids,
755		retractall(not_invariant_checked(_)),
756		reset_not_interesting,
757		retractall(max_reached_for_node(_)),
758		retractall(time_out_for_node(_,_,_)),
759		retractall(time_out_for_invariant(_)),
760		retractall(time_out_for_assertions(_)),
761		retractall(use_no_timeout(_)),
762		retractall(state_error(_,_,_)),
763		clear_context_state,
764		reset_transition_store,
765		retractall(operation_not_yet_covered(_)),
766		retractall(hash_to_id(_,_)),
767		retractall(id_back_edge(_,_,_)),
768		retractall(hash_to_nauty_id(_,_)),
769		retractall(id_to_marker(_,_)),
770		retractall(specialized_inv(_,_)),
771		%retractall(reuse_operation(_,_,_,_)),
772		retractall(history(_)),
773		retractall(forward_history(_)),
774		retractall(op_trace_ids(_)),
775		retractall(current_state_id(_)),
776		retractall(current_options(_)).
777
778		% this is only used from within the Tcl/Tk animator at the moment:
779		delete_node(ID) :- print(deleting(ID)),nl,
780		retractall_visited_expression(ID),
781		retractall_invariant_violated(ID),
782		retract_open_node_and_update_processed_nodes(ID),
783		retractall(not_invariant_checked(ID)),
784		(retract(not_interesting(ID)) -> inc_counter_by(not_interesting_nodes,-1) ; true),
785		retractall(max_reached_for_node(ID)),
786		retractall(time_out_for_node(ID,_,_)),
787		retractall(time_out_for_invariant(ID)),
788		retractall(time_out_for_assertions(ID)),
789		retractall(use_no_timeout(ID)),
790		retractall(state_error(ID,_,_)),
791		retractall(transition(ID,_,_,_)),
792		% to do: check if operation_not_yet_covered(_) changes
793		retract_hash(ID),
794		retractall(id_to_marker(ID,_)).
795
796		retract_hash(ID) :- retract(hash_to_id(Hash,ID)), retractall(hash_to_nauty_id(_TermHash,Hash)),fail.
797		retract_hash(_).
798
799		assert_max_reached_for_node(Id) :- %print_message(max_reached_for_node(Id)),
800		(max_reached_for_node(Id) -> true ; assertz(max_reached_for_node(Id))).
801
802		:- use_module(probsrc(debug),[debug_mode/1]).
803		assert_time_out_for_node(Id,OpName,TypeOfTimeOut) :-
804		(debug_mode(off),functor(TypeOfTimeOut,virtual_time_out,_) -> true % can easily happen when parameters are unbounded
805		; print_message(time_out_for_node(Id,OpName,TypeOfTimeOut))),
806		(time_out_for_node(Id,OpName,_) -> true ; assertz(time_out_for_node(Id,OpName,TypeOfTimeOut))).
807		assert_time_out_for_invariant(Id) :- print_message(time_out_for_invariant(Id)),
808		(time_out_for_invariant(Id) -> true ; assertz(time_out_for_invariant(Id))).
809		assert_time_out_for_assertions(Id) :- print_message(time_out_for_assertions(Id)),
810		(time_out_for_assertions(Id) -> true ; assertz(time_out_for_assertions(Id))).
811
812		max_reached_or_timeout_for_node(Id) :-
813		(max_reached_for_node(Id) ; time_out_for_node(Id,_,_)).
814		/* ---------------------- */
815		/* state space saving */
816		/* ---------------------- */
817
818		:- dynamic state_space_version_in_file/1. %
819		state_space_version(1).
820
821		check_state_space_version :- state_space_version(V),
822		(state_space_version_in_file(F) -> true ; F=0),
823		(V>F -> add_message(state_space,'Warning: saved state_space may be incompatible with current version: ',F:V) ; true).
824
825		% save all infos of state space (transitions, evaluated invariants, ...)
826		tcltk_save_state_space(File) :-
827		print('% saving full state space to: '), print(File),nl,
828		open(File,write,Stream,[encoding(utf8)]),
829		print_state_space(Stream),
830		close(Stream),
831		print_message(done).
832
833
834		:- use_module(tools_printing, [print_dynamic_fact/2,print_dynamic_pred/4]).
835		print_state_space(Stream) :-
836		state_space_version(V),
837		print_dynamic_fact(Stream,state_space_version_in_file(V)),
838		% TO DO: maybe also save some important preferences, and warn user and/or propose to adapt preferences ?
839		print_dynamic_pred(Stream,state_space,history,1),
840		print_dynamic_pred(Stream,state_space,forward_history,1),
841		print_dynamic_pred(Stream,state_space,op_trace_ids,1),
842		print_dynamic_pred(Stream,state_space,current_state_id,1),
843		print_dynamic_pred(Stream,state_space,current_options,1),
844		print_dynamic_pred(Stream,state_space,packed_visited_expression,2),
845		print_dynamic_pred(Stream,state_space,not_invariant_checked,1),
846		print_dynamic_pred(Stream,state_space,not_interesting,1),
847		print_dynamic_pred(Stream,state_space,max_reached_for_node,1),
848		print_dynamic_pred(Stream,state_space,time_out_for_node,3),
849		print_dynamic_pred(Stream,state_space,use_no_timeout,1),
850		print_dynamic_pred(Stream,state_space,transition,4),
851		print_dynamic_pred(Stream,state_space,transition_info,2),
852		print_dynamic_pred(Stream,state_space,operation_not_yet_covered,1),
853		print_dynamic_pred(Stream,state_space,state_error,3),
854		print_state_space_open_nodes(Stream),
855		print_stored_values(Stream),
856		get_counter(states,X),
857		write_term(Stream,saved_gennum_count(X),[quoted(true)]),write(Stream,'.'),nl(Stream).
858
859		saved_gennum_count(99999).
860
861		/* ---------------------- */
862		/* state space loading */
863		/* ---------------------- */
864
865		tcltk_load_state(File) :- state_space_clean_all,
866		print('Loading: '), print(File),nl,
867		user_consult_without_redefine_warning(File), % this will read in bind_skeleton/2, ..., next_value_id/1
868		check_state_space_version,
869		print('Generating open node info'),nl,
870		transfer_open_node_info,
871		print('Transfer state packing info'),nl,
872		transfer_state_packing_info,
873		print('Recomputing hash index'),nl,
874		recompute_all_hash,
875		(saved_gennum_count(X) -> reset_state_counter(X) ; true),
876		reset_processed_nodes_counter, % TO DO: restore or save it
877		reset_next_state_error_id_counter, % DITTO
878		print('Done'),nl,!.
879		tcltk_load_state(File) :-
880		add_error(tcltk_load_state,'Could not load state from file: ',File),
881		state_space_initialise.
882
883		:- dynamic not_all_z_saved/1, not_all_transitions_added_saved/1.
884		:- dynamic bind_skeleton/2, stored_value/2, stored_value_hash_to_id/2, next_value_id/1.
885
886		% transfer facts read into state_space into other modules:
887		transfer_open_node_info :- retract(not_all_z_saved(X)), %print(not_all_z(X)),nl,
888		assert_not_all_z(X),fail.
889		transfer_open_node_info :- retract(not_all_transitions_added_saved(X)),
890		assert_not_all_transitions_added(X),fail.
891		transfer_open_node_info.
892		% now for transferring to state_packing module info generated by print_stored_values
893		transfer_state_packing_info :- retract(bind_skeleton(X,Y)), %print(skel(X)),nl,
894		assertz(state_packing:bind_skeleton(X,Y)),fail.
895		transfer_state_packing_info :- retract(stored_value(X,Y)),
896		assertz(state_packing:stored_value(X,Y)),fail.
897		transfer_state_packing_info :- retract(stored_value_hash_to_id(X,Y)),
898		assertz(state_packing:stored_value_hash_to_id(X,Y)),fail.
899		transfer_state_packing_info :- retract(next_value_id(X)),
900		state_packing:set_next_value_id(X),fail.
901		transfer_state_packing_info.
902
903		recompute_all_hash :-
904		retractall(hash_to_id(_,_)),retractall(id_to_marker(_,_)),
905		retractall(hash_to_nauty_id(_,_)),
906		visited_expression(ID,StateTemplate),
907		state_space_exploration_modes:compute_hash(StateTemplate,Hash,Marker),
908		assertz(hash_to_id(Hash,ID)),
909		assertz(id_to_marker(ID,Marker)),
910		fail.
911		recompute_all_hash.
912
913		:- use_module(hashing,[my_term_hash/2]).
914		% generates a hash for the entire state space not depending on the order in which states where added
915		compute_full_state_space_hash(Hash) :-
916		%listing(hash_to_id/2), listing(packed_visited_expression/2),
917		findall(Hash,hash_to_id(Hash,_),ListOfHashCodes),
918		sort(ListOfHashCodes,SortedList),
919		my_term_hash(SortedList,Hash).
920		% TO DO: also provide transition hashes
921
922		:- use_module(tools_meta,[safe_on_exception/3]).
923		user_consult_without_redefine_warning(File) :-
924		get_set_optional_prolog_flag(redefine_warnings, Old, off),
925		get_set_optional_prolog_flag(single_var_warnings, Old2, off),
926		(safe_on_exception(Exc,
927		%consult(File), %
928		load_files([File], [load_type(source),compilation_mode(consult),encoding(utf8)]),
929		(nl,print('Exception occurred:'),print(Exc),nl,fail))
930		-> OK=true ; OK=false),
931		get_set_optional_prolog_flag(redefine_warnings, _, Old),
932		get_set_optional_prolog_flag(single_var_warnings, _, Old2),
933		OK=true.
934
935
936
937		execute_id_trace_from_current(ID,OpIDL,StateIDList) :-
938		current_state_id(CurID),
939		reverse([CurID|StateIDList],Rev),
940		Rev = [Dest|TRev], (Dest==ID -> true ; print(not_eq(Dest,ID)),nl),
941		retract(history(H)),
942		update_forward_history(OpIDL), % check if OpIDL conforms to forward history and keep it
943		append(TRev,H,NewH),
944		assertz(history(NewH)),
945		retract(op_trace_ids(OldTrace)),
946		reverse(OpIDL,NewTrace),
947		append(NewTrace,OldTrace,Trace),
948		assertz(op_trace_ids(Trace)),
949		retractall(current_state_id(_)),
950		assertz(current_state_id(ID)).
951		%execute_trace_to_node(OpL,StateIDList). /* <----- BOTTLENECK FOR LONG SEQUENCES */
952		%generate_trace([],Acc,Acc).
953		%generate_trace([OpTerm|T],Acc,Res) :-
954		% translate:translate_event(OpTerm,OpString),
955		% generate_trace(T,[action(OpString,OpTerm)|Acc],Res).
956
957		update_forward_history(TransitionIds) :-
958		(retract(forward_history(Forward)),
959		prune_forward_history(TransitionIds,Forward,NewForward)
960		-> assert(forward_history(NewForward))
961		; true).
962		% try and prune forward history if it matches operation trace
963		prune_forward_history([],ForwardHistory,ForwardHistory).
964		prune_forward_history([TransID|T],[forward(_,TransID)|TF],Res) :-
965		prune_forward_history(T,TF,Res).
966
967		try_set_trace_by_transition_ids(TransIds) :-
968		(set_trace_by_transition_ids(TransIds) -> true
969		; add_internal_error('Call failed:',set_trace_by_transition_ids(TransIds))).
970
971		set_trace_by_transition_ids(TransitionIds) :-
972		extract_history_from_transition_ids(TransitionIds,root,[],[],Last,History,OpTrace),
973		%visited_expression(Last,LastState,LastCond),
974		retractall(history(_)),
975		retractall(forward_history(_)), % TODO: we could try and recover a new forward history if transition ids match current history^forward history
976		update_forward_history(TransitionIds),
977		retractall(current_state_id(_)),
978		retractall(op_trace_ids(_)),
979		assertz(history(History)),
980		assertz(op_trace_ids(OpTrace)),
981		assertz(current_state_id(Last)).
982
983
984		extract_history_from_transition_ids([],CurrentState,History,Trace,CurrentState,History,Trace).
985		extract_history_from_transition_ids([TransId|Rest],CurrentState,AccHist,AccTrace,Last,History,Trace) :-
986		transition(CurrentState,_,TransId,DestState),!,
987		extract_history_from_transition_ids(Rest,DestState,[CurrentState|AccHist],
988		[TransId|AccTrace],Last,History,Trace).
989		extract_history_from_transition_ids([TransId|_],CurrentState,_,_,_,_,_Trace) :-
990		add_error(state_space,'Could not execute transition id: ', TransId:from(CurrentState)),fail.
991
992		% extend trace from current state
993		extend_trace_by_transition_ids(TransitionIds) :-
994		current_state_id(CurID),
995		history(OldH), op_trace_ids(OldOT),
996		extract_history_from_transition_ids(TransitionIds,CurID,OldH,OldOT,Last,History,OpTrace),
997		retractall(history(_)), retractall(forward_history(_)),
998		retractall(current_state_id(_)),
999		retractall(op_trace_ids(_)),
1000		assertz(history(History)),
1001		assertz(op_trace_ids(OpTrace)),
1002		assertz(current_state_id(Last)).
1003
1004		/* --------------------------------- */
1005		:- dynamic max_nr_of_new_nodes/1.
1006
1007		% negative number or non-number signifies no limit
1008		set_max_nr_of_new_impl_trans_nodes(MaxNrOfNewNodes) :-
1009		retractall(max_nr_of_new_nodes(_)),
1010		(number(MaxNrOfNewNodes), MaxNrOfNewNodes>=0
1011		-> assertz(max_nr_of_new_nodes(MaxNrOfNewNodes))
1012		; true). % no need to store limit; we will explore as much as needed
1013
1014		get_max_nr_of_new_impl_trans_nodes(MaxNrOfNewNodes) :-
1015		(max_nr_of_new_nodes(Max) -> MaxNrOfNewNodes=Max; MaxNrOfNewNodes = 0).
1016
1017		% used e.g., in refinement or ltl checker
1018		impl_trans_term(From,ActionAsTerm,To) :-
1019		compute_transitions_if_necessary_saved(From),
1020		transition(From,ActionAsTerm,_TID,To).
1021
1022		% a variation also giving the transition id:
1023		impl_trans_id(From,ActionAsTerm,TransitionID,To) :-
1024		compute_transitions_if_necessary_saved(From),
1025		transition(From,ActionAsTerm,TransitionID,To).
1026
1027		impl_trans_term_all(From,Ops) :-
1028		compute_transitions_if_necessary_saved(From),
1029		findall(op(Id,ActionAsTerm,To),
1030		transition(From,ActionAsTerm,Id,To),
1031		Ops).
1032
1033		% true if e.g., a time-out occurred during computation of all transitions
1034		impl_trans_not_complete(From) :- max_reached_or_timeout_for_node(From).
1035
1036		compute_transitions_if_necessary_saved(From) :-
1037		catch(
1038		compute_transitions_if_necessary(From),
1039		error(forced_interrupt_error('User has interrupted the current execution'),_),
1040		user_interrupts:process_interrupted_error_message).
1041
1042		:- use_module(tcltk_interface,[compute_all_transitions_if_necessary/2]).
1043		compute_transitions_if_necessary(From) :-
1044		not_all_transitions_added(From),!,
1045		decrease_max_nr_of_new_nodes(From),
1046		compute_all_transitions_if_necessary(From,false).
1047		compute_transitions_if_necessary(_From).
1048
1049		decrease_max_nr_of_new_nodes(ID) :-
1050		retract(max_nr_of_new_nodes(Max)),!,
1051		( Max>0 ->
1052		NewMax is Max-1,
1053		assertz(max_nr_of_new_nodes(NewMax))
1054		; Max=0 -> NM is -1,
1055		assertz(max_nr_of_new_nodes(NM)),
1056		add_warning(state_space,'Maximum number of new nodes reached for CTL/LTL/refinement check, node id = ',ID),
1057		fail
1058		; % negative number: re-assert and fail
1059		assertz(max_nr_of_new_nodes(Max)),
1060		fail).
1061		decrease_max_nr_of_new_nodes(_). % no limit stored; just proceed
1062
1063		% will be called from TCL/TK side
1064		max_nr_of_new_nodes_limit_not_reached :-
1065		max_nr_of_new_nodes(N),N>0.
1066
1067		:- use_module(specfile,[b_or_z_mode/0, csp_mode/0, csp_with_bz_mode/0]).
1068		retract_open_node(NodeID) :- retract_open_node_and_update_processed_nodes(NodeID),
1069		(b_or_z_mode -> assertz(not_invariant_checked(NodeID)) ; true).
1070
1071		reset_processed_nodes_counter :- reset_counter(processed_nodes).
1072		%reset_processed_nodes_counter(Nr) :- set_counter(processed_nodes,Nr).
1073
1074		retract_open_node_and_update_processed_nodes(NodeID) :-
1075		retract_open_node_direct(NodeID),
1076		inc_processed.
1077
1078		inc_processed :-
1079		inc_counter(processed_nodes).
1080
1081		pop_id_from_front(ID) :- pop_id_from_front_direct(ID), inc_processed.
1082		pop_id_from_end(ID) :- pop_id_from_end_direct(ID), inc_processed.
1083		pop_id_oldest(ID) :- pop_id_oldest_direct(ID), inc_processed.
1084
1085
1086
1087		/* --------------------------------- */
1088
1089		% find initialised states; very similar to is_initial_state_id/1
1090		% but is used by ltl/ctl/sap
1091		% TO DO: merge these two variations of the same concept
1092
1093		:- use_module(specfile,[animation_mode/1]).
1094
1095		find_initialised_states(Init) :-
1096		animation_mode(Mode),
1097		( init_states_mode_cst_init(Mode) ->
1098		findall(I,find_init1(root,I,_),Init)
1099		; init_states_mode_one_step(Mode) ->
1100		next_states_from_root(Init)
1101		;
1102		fail).
1103
1104		% find trace to some initialised state
1105		find_trace_to_initial_state(Target,Trace) :- animation_mode(Mode),
1106		find_aux(Mode,Target,Trace).
1107		find_aux(Mode,Target,[root,Target]) :-
1108		init_states_mode_one_step(Mode).
1109		find_aux(Mode,Target,[root|Trace]) :-
1110		init_states_mode_cst_init(Mode),
1111		find_init1(root,Target,Trace).
1112
1113
1114		init_states_mode_cst_init(b).
1115		init_states_mode_cst_init(z).
1116		init_states_mode_cst_init(csp_and_b).
1117
1118		init_states_mode_one_step(csp).
1119		init_states_mode_one_step(cspm).
1120		init_states_mode_one_step(xtl).
1121		%init_states_mode_one_step(promela).
1122
1123		next_states_from_root(States) :-
1124		impl_trans_term_all(root,Ops),
1125		findall(S, member(op(_Id,_,S),Ops), States).
1126
1127		find_init1(Start,Init,Trace) :- Start==Init,!,Trace=[]. % usually called with Start=Init=root
1128		find_init1(Start,Init,[State|Rest]) :-
1129		impl_trans_term(Start,O,State),
1130		find_init2(O,State,Init,Rest).
1131		find_init2(O,Init,Init,[]) :-
1132		has_functor_and_maybe_tau(O,'$initialise_machine').
1133		find_init2(O,State,Init,Path) :-
1134		has_functor_and_maybe_tau(O,'$setup_constants'),
1135		find_init1(State,Init,Path).
1136		find_init2(start_cspm_MAIN,State,Init,Path) :-
1137		find_init1(State,Init,Path).
1138		find_init2(start_cspm(_Proc),State,Init,Path) :-
1139		find_init1(State,Init,Path).
1140
1141		% has_functor_and_maybe_tau(Term,Functor)
1142		% checks if Term has the form "Functor(...)" or "tau(Functor(...))"
1143		% this is used for CSP||B specification where the initialisation is wrapped with
1144		% in a tau operator
1145		has_functor_and_maybe_tau(tau(Term),Functor) :-
1146		has_functor_and_maybe_tau(Term,Functor),!.
1147		has_functor_and_maybe_tau(Term,Functor) :-
1148		functor(Term,Functor,_).
1149
1150		% compute how far the state is from the root node using back_edge markers (if available)
1151		try_compute_depth_of_state_id(root,R) :- !, R=0.
1152		try_compute_depth_of_state_id(Node,Depth) :- id_back_edge(Node,Depth,_Back).
1153
1154		% optional registering of back_edges: to quickly find trace from root and to computed depth/diameter
1155		register_back_edge(ID,FromID) :-
1156		try_compute_depth_of_state_id(FromID,D),!,
1157		D1 is D+1,
1158		assertz(id_back_edge(ID,D1,FromID)).
1159		register_back_edge(ID,FromID) :- write(cannot_store_back_edge(ID,FromID)),nl.
1160
1161		/* --------------------------------- */
1162
1163		%
1164		% Code to compute equivalence classes
1165		% using the standard DFA minimization algorithm
1166
1167		:- dynamic equivalent/2.
1168		% state_space:compute_equivalence_classes
1169		:- public compute_equivalence_classes/0.
1170
1171		compute_equivalence_classes :- init_equi,
1172		split_equivalence_classes,nl,
1173		print_equi.
1174
1175		print_equi :- state_space:equivalent(A,B), visited_expression(A,State),
1176		visited_expression(B,StateB),
1177		nl,
1178		print(A), print(' : '), print(State),nl,
1179		print(B), print(' : '), print(StateB),nl,fail.
1180		print_equi.
1181
1182		init_equi :- retractall(equivalent(_,_)),
1183		packed_visited_expression(ID,_State),
1184		\+ not_all_transitions_added(ID),
1185		findall(Action,transition(ID,Action,_,_),List),
1186		packed_visited_expression(ID2,_S2), ID2 @> ID,
1187		\+ not_all_transitions_added(ID2),
1188		findall(Action,transition(ID2,Action,_,_),List),
1189		assertz(equivalent(ID,ID2)), % they have the same signature
1190		%print(equivalent(ID,ID2)),nl,
1191		fail.
1192		init_equi :- print(finished_initialising),nl.
1193
1194		split_equivalence_classes :- retractall(echange),
1195		equivalent(ID1,ID2),
1196		transition(ID1,A,_,Dest1),
1197		transition(ID2,A,_,Dest2),
1198		\+ check_equi(Dest1,Dest2),
1199		retract(equivalent(ID1,ID2)), % splitting class
1200		% print(diff(ID1,ID2, A, Dest1, Dest2)),nl,
1201		assert_echange,
1202		fail.
1203		split_equivalence_classes :- echange -> split_equivalence_classes ; true.
1204
1205		:- dynamic echange/0.
1206		assert_echange :- echange -> true ; assertz(echange),print('.'),flush_output.
1207
1208		check_equi(A,B) :- A=B -> true ; A @<B -> equivalent(A,B) ; equivalent(B,A).
1209
1210		/*
1211		% benchmark how much time it takes to copy the state space state_space:bench_state_space.
1212		bench_state_space :-
1213		statistics(walltime,_),
1214		(state_space:packed_visited_expression(ID,S), assertz(pve(ID,S)),fail ; true),
1215		statistics(walltime,[_,Delta]), format('Time to copy packed_visited_expression: ~w ms~n',[Delta]),
1216		(state_space:transition(A,B,C,D), assertz(tr(A,B,C,D)),fail ; true),
1217		statistics(walltime,[_,Delta2]), format('Time to copy transition: ~w ms~n',[Delta2]),
1218		(state_packing:stored_value(A,B), assertz(sv(A,B)),fail ; true),
1219		(state_packing:stored_value_hash_to_id(A,B), assertz(svhi(A,B)),fail ; true),
1220		statistics(walltime,[_,Delta3]), format('Time to copy stored_value: ~w ms~n',[Delta3]).
1221		*/
1222
1223		:- public portray_state_space/0.
1224		portray_state_space :- packed_visited_expression(ID,S), functor(S,F,N),
1225		format('State ~w : ~w/~w~n',[ID,F,N]), fail.
1226		portray_state_space :- transition(ID,Action,TransID,DestID),
1227		format(' ~w: ~w -- ~w --> ~w~n',[TransID,ID,Action,DestID]),fail.
1228		portray_state_space.
1229
1230		bench_state_space :- statistics(walltime,[W1,_]),
1231		(packed_visited_expression(_,_), fail ; true),
1232		statistics(walltime,[W2,_]), T1 is W2-W1,
1233		format('Time to inspect all states: ~w ms walltime~n',[T1]),
1234		(visited_expression(_,_), fail ; true),
1235		statistics(walltime,[W3,_]), T2 is W3-W2,
1236		format('Time to inspect and unpack all states: ~w ms walltime~n',[T2]),
1237		(transition(_,_,_,_), fail ; true),
1238		statistics(walltime,[W4,_]), T3 is W4-W3,
1239		format('Time to inspect all transitions: ~w ms walltime~n',[T3]),
1240		(visited_expression(_,E), my_term_hash(E,_), fail ; true),
1241		statistics(walltime,[W5,_]), T4 is W5-W4,
1242		format('Time to inspect, unpack and hash all states: ~w ms walltime~n',[T4]).
1243
1244		% ----------------------------
1245		% COUNTER EXAMPLE MANAGEMENT
1246
1247		% store counter example nodes and transition ids; used by LTL model checking for example
1248
1249
1250		:- dynamic counterexample_node/1.
1251		:- dynamic counterexample_op/1.
1252
1253		add_counterexample_node(NodeID) :- assertz(counterexample_node(NodeID)).
1254		add_counterexample_op(TransID) :-
1255		(counterexample_op(TransID) -> true ; assertz(counterexample_op(TransID))).
1256
1257
1258		reset_counterexample :-
1259		retractall(counterexample_node(_)),
1260		retractall(counterexample_op(_)).
1261
1262		:- register_event_listener(play_counterexample,reset_counterexample,
1263		'Reset marked nodes from previous counterexamples.').
1264
1265		set_counterexample_by_transition_ids(TransIds) :-
1266		set_trace_by_transition_ids(TransIds),
1267		maplist(add_counterexample_op,TransIds),
1268		extract_history_from_transition_ids(TransIds,root,[],[],_Last,History,_OpTrace),
1269		maplist(add_counterexample_node,History).