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model-checker : minor fix in ddfs algorithm
[simgrid.git] / src / mc / mc_liveness.c
1 /* Copyright (c) 2011-2013 Da SimGrid Team. All rights reserved.            */
2
3 /* This program is free software; you can redistribute it and/or modify it
4  * under the terms of the license (GNU LGPL) which comes with this package. */
5
6 #include "mc_private.h"
7 #include <unistd.h>
8 #include <sys/wait.h>
9
10 XBT_LOG_NEW_DEFAULT_SUBCATEGORY(mc_liveness, mc,
11                                 "Logging specific to algorithms for liveness properties verification");
12
13 /********* Global variables *********/
14
15 xbt_dynar_t acceptance_pairs;
16 xbt_dynar_t visited_pairs;
17 xbt_dynar_t successors;
18
19
20 /********* Static functions *********/
21
22 static xbt_dynar_t get_atomic_propositions_values(){
23   int res;
24   int_f_void_t f;
25   unsigned int cursor = 0;
26   xbt_automaton_propositional_symbol_t ps = NULL;
27   xbt_dynar_t values = xbt_dynar_new(sizeof(int), NULL);
28
29   xbt_dynar_foreach(_mc_property_automaton->propositional_symbols, cursor, ps){
30     f = (int_f_void_t)ps->function;
31     res = f();
32     xbt_dynar_push_as(values, int, res);
33   }
34
35   return values;
36 }
37
38 static int is_reached_acceptance_pair(mc_pair_t pair){
39
40   int raw_mem_set = (mmalloc_get_current_heap() == raw_heap);
41  
42   if(xbt_dynar_is_empty(acceptance_pairs)){
43
44     MC_SET_RAW_MEM;
45     if(pair->graph_state->system_state == NULL){
46       pair->graph_state->system_state = MC_take_snapshot();
47       pair->heap_bytes_used = mmalloc_get_bytes_used(std_heap);
48     }
49     xbt_dynar_push(acceptance_pairs, &pair); 
50     MC_UNSET_RAW_MEM;
51
52     if(raw_mem_set)
53       MC_SET_RAW_MEM;
54
55     return -1;
56
57   }else{
58
59     MC_SET_RAW_MEM;
60
61     if(pair->graph_state->system_state == NULL){
62       pair->graph_state->system_state = MC_take_snapshot();
63       pair->heap_bytes_used = mmalloc_get_bytes_used(std_heap);
64     }
65
66     size_t current_bytes_used = pair->heap_bytes_used;
67     int current_nb_processes = pair->nb_processes;
68
69     unsigned int cursor = 0;
70     int previous_cursor = 0, next_cursor = 0;
71     int start = 0;
72     int end = xbt_dynar_length(acceptance_pairs) - 1;
73
74     mc_pair_t pair_test = NULL;
75     size_t bytes_used_test;
76     int nb_processes_test;
77     int same_processes_and_bytes_not_found = 1;
78
79     while(start <= end && same_processes_and_bytes_not_found){
80       cursor = (start + end) / 2;
81       pair_test = (mc_pair_t)xbt_dynar_get_as(acceptance_pairs, cursor, mc_pair_t);
82       bytes_used_test = pair_test->heap_bytes_used;
83       nb_processes_test = pair_test->nb_processes;
84       if(nb_processes_test < current_nb_processes)
85         start = cursor + 1;
86       else if(nb_processes_test > current_nb_processes)
87         end = cursor - 1; 
88       else if(nb_processes_test == current_nb_processes){
89         if(bytes_used_test < current_bytes_used)
90           start = cursor + 1;
91         else if(bytes_used_test > current_bytes_used)
92           end = cursor - 1;
93         else if(bytes_used_test == current_bytes_used){
94           same_processes_and_bytes_not_found = 0;
95           if(xbt_automaton_state_compare(pair_test->automaton_state, pair->automaton_state) == 0){
96             if(xbt_automaton_propositional_symbols_compare_value(pair_test->atomic_propositions, pair->atomic_propositions) == 0){
97               XBT_DEBUG("Compare with state %d", pair_test->num);
98               if(snapshot_compare(pair->graph_state->system_state, pair_test->graph_state->system_state) == 0){
99                 if(raw_mem_set)
100                   MC_SET_RAW_MEM;
101                 else
102                   MC_UNSET_RAW_MEM;
103                 return pair_test->num;
104               }
105             }
106           }
107           /* Search another pair with same number of bytes used in std_heap */
108           previous_cursor = cursor - 1;
109           while(previous_cursor >= 0){
110             pair_test = (mc_pair_t)xbt_dynar_get_as(acceptance_pairs, previous_cursor, mc_pair_t);
111             bytes_used_test = pair_test->heap_bytes_used;
112             if(bytes_used_test != current_bytes_used)
113               break;
114             if(xbt_automaton_state_compare(pair_test->automaton_state, pair->automaton_state) == 0){
115               if(xbt_automaton_propositional_symbols_compare_value(pair_test->atomic_propositions, pair->atomic_propositions) == 0){  
116                 XBT_DEBUG("Compare with state %d", pair_test->num);
117                 if(snapshot_compare(pair->graph_state->system_state, pair_test->graph_state->system_state) == 0){
118                   if(raw_mem_set)
119                     MC_SET_RAW_MEM;
120                   else
121                     MC_UNSET_RAW_MEM;
122                   return pair_test->num;
123                 }
124               }
125             }
126             previous_cursor--;
127           }
128           next_cursor = cursor + 1;
129           while(next_cursor < xbt_dynar_length(acceptance_pairs)){
130             pair_test = (mc_pair_t)xbt_dynar_get_as(acceptance_pairs, next_cursor, mc_pair_t);
131             bytes_used_test = pair_test->heap_bytes_used;
132             if(bytes_used_test != current_bytes_used)
133               break;
134             if(xbt_automaton_state_compare(pair_test->automaton_state, pair->automaton_state) == 0){
135               if(xbt_automaton_propositional_symbols_compare_value(pair_test->atomic_propositions, pair->atomic_propositions) == 0){
136                 XBT_DEBUG("Compare with state %d", pair_test->num);
137                 if(snapshot_compare(pair->graph_state->system_state, pair_test->graph_state->system_state) == 0){
138                   if(raw_mem_set)
139                     MC_SET_RAW_MEM;
140                   else
141                     MC_UNSET_RAW_MEM;
142                   return pair_test->num;
143                 }
144               }
145             }
146             next_cursor++;
147           }
148         }
149       }
150     }
151
152     pair_test = (mc_pair_t)xbt_dynar_get_as(acceptance_pairs, cursor, mc_pair_t);
153     bytes_used_test = pair_test->heap_bytes_used;
154
155     if(bytes_used_test < current_bytes_used)
156       xbt_dynar_insert_at(acceptance_pairs, cursor + 1, &pair);
157     else
158       xbt_dynar_insert_at(acceptance_pairs, cursor, &pair);
159        
160     
161     MC_UNSET_RAW_MEM;
162
163     if(raw_mem_set)
164       MC_SET_RAW_MEM;
165     
166     return -1;
167     
168   }
169  
170 }
171
172
173 static void set_acceptance_pair_reached(mc_pair_t pair){
174
175   int raw_mem_set = (mmalloc_get_current_heap() == raw_heap);
176
177   if(xbt_dynar_is_empty(acceptance_pairs)){
178
179      MC_SET_RAW_MEM;
180      if(pair->graph_state->system_state == NULL){
181        pair->graph_state->system_state = MC_take_snapshot();
182        pair->heap_bytes_used = mmalloc_get_bytes_used(std_heap);
183      }
184      xbt_dynar_push(acceptance_pairs, &pair); 
185      MC_UNSET_RAW_MEM;
186
187   }else{
188
189     MC_SET_RAW_MEM;
190
191     if(pair->graph_state->system_state == NULL){
192       pair->graph_state->system_state = MC_take_snapshot();
193       pair->heap_bytes_used = mmalloc_get_bytes_used(std_heap);
194     }
195     
196     size_t current_bytes_used = pair->heap_bytes_used;
197     int current_nb_processes = pair->nb_processes;
198
199     unsigned int cursor = 0;
200     int start = 0;
201     int end = xbt_dynar_length(acceptance_pairs) - 1;
202
203     mc_pair_t pair_test = NULL;
204     size_t bytes_used_test = 0;
205     int nb_processes_test;
206
207     while(start <= end){
208       cursor = (start + end) / 2;
209       pair_test = (mc_pair_t)xbt_dynar_get_as(acceptance_pairs, cursor, mc_pair_t);
210       bytes_used_test = pair_test->heap_bytes_used;
211       nb_processes_test = pair_test->nb_processes;
212       if(nb_processes_test < current_nb_processes)
213         start = cursor + 1;
214       if(nb_processes_test > current_nb_processes)
215         end = cursor - 1; 
216       if(nb_processes_test == current_nb_processes){
217         if(bytes_used_test < current_bytes_used)
218           start = cursor + 1;
219         if(bytes_used_test > current_bytes_used)
220           end = cursor - 1;
221         if(bytes_used_test == current_bytes_used)
222           break;
223       }
224     }
225
226     if(bytes_used_test < current_bytes_used)
227       xbt_dynar_insert_at(acceptance_pairs, cursor + 1, &pair);
228     else
229       xbt_dynar_insert_at(acceptance_pairs, cursor, &pair);
230     
231     MC_UNSET_RAW_MEM;
232     
233   }
234
235   if(raw_mem_set)
236     MC_SET_RAW_MEM;
237     
238 }
239
240 static void remove_acceptance_pair(mc_pair_t pair){
241
242   unsigned int cursor = 0;
243   mc_pair_t pair_test;
244   int pair_found = 0;
245
246   xbt_dynar_foreach(acceptance_pairs, cursor, pair_test){
247     if(pair_test->num == pair->num){
248       pair_found = 1;
249       break;
250     }
251   }
252
253   if(pair_found)
254     xbt_dynar_remove_at(acceptance_pairs, cursor, NULL);
255   
256   pair->acceptance_removed = 1;
257
258   if(pair->stack_removed && pair->acceptance_removed){
259     if(_sg_mc_visited == 0){
260       MC_pair_delete(pair);
261     }else if(pair->visited_removed){
262       MC_pair_delete(pair);
263     }
264   }
265
266 }
267
268 static int is_visited_pair(mc_pair_t pair){
269
270   if(_sg_mc_visited == 0)
271     return -1;
272
273   int raw_mem_set = (mmalloc_get_current_heap() == raw_heap);
274
275   if(xbt_dynar_is_empty(visited_pairs)){
276
277     MC_SET_RAW_MEM;
278     if(pair->graph_state->system_state == NULL)
279       pair->graph_state->system_state = MC_take_snapshot();
280     xbt_dynar_push(visited_pairs, &pair); 
281     MC_UNSET_RAW_MEM;
282
283     if(raw_mem_set)
284       MC_SET_RAW_MEM;
285
286     return -1;
287
288   }else{
289
290     MC_SET_RAW_MEM;
291
292     if(pair->graph_state->system_state == NULL)
293       pair->graph_state->system_state = MC_take_snapshot();
294     
295     size_t current_bytes_used = pair->heap_bytes_used;
296     int current_nb_processes = pair->nb_processes;
297
298     unsigned int cursor = 0;
299     int previous_cursor = 0, next_cursor = 0;
300     int start = 0;
301     int end = xbt_dynar_length(visited_pairs) - 1;
302
303     mc_pair_t pair_test = NULL;
304     size_t bytes_used_test;
305     int nb_processes_test;
306     int same_processes_and_bytes_not_found = 1;
307
308     while(start <= end && same_processes_and_bytes_not_found){
309       cursor = (start + end) / 2;
310       pair_test = (mc_pair_t)xbt_dynar_get_as(visited_pairs, cursor, mc_pair_t);
311       bytes_used_test = pair_test->heap_bytes_used;
312       nb_processes_test = pair_test->nb_processes;
313       if(nb_processes_test < current_nb_processes)
314         start = cursor + 1;
315       else if(nb_processes_test > current_nb_processes)
316         end = cursor - 1; 
317       else if(nb_processes_test == current_nb_processes){
318         if(bytes_used_test < current_bytes_used)
319           start = cursor + 1;
320         else if(bytes_used_test > current_bytes_used)
321           end = cursor - 1;
322         else if(bytes_used_test == current_bytes_used){
323           same_processes_and_bytes_not_found = 0;
324           if(xbt_automaton_state_compare(pair_test->automaton_state, pair->automaton_state) == 0){
325             if(xbt_automaton_propositional_symbols_compare_value(pair_test->atomic_propositions, pair->atomic_propositions) == 0){
326               if(snapshot_compare(pair->graph_state->system_state, pair_test->graph_state->system_state) == 0){
327                 if(pair_test->other_num == -1)
328                   pair->other_num = pair_test->num;
329                 else
330                   pair->other_num = pair_test->other_num;
331                 if(dot_output == NULL)
332                   XBT_DEBUG("Pair %d already visited ! (equal to pair %d)", pair->num, pair_test->num);
333                 else
334                   XBT_DEBUG("Pair %d already visited ! (equal to pair %d (pair %d in dot_output))", pair->num, pair_test->num, pair->other_num);
335                 xbt_dynar_remove_at(visited_pairs, cursor, NULL);
336                 xbt_dynar_insert_at(visited_pairs, cursor, &pair);
337                 pair_test->visited_removed = 1;
338                 if(pair_test->stack_removed && pair_test->visited_removed){
339                   if((pair_test->automaton_state->type == 1) || (pair_test->automaton_state->type == 2)){
340                     if(pair_test->acceptance_removed){ 
341                       MC_pair_delete(pair_test);
342                     }
343                   }else{
344                     MC_pair_delete(pair_test);
345                   }     
346                 }
347                 if(raw_mem_set)
348                   MC_SET_RAW_MEM;
349                 else
350                   MC_UNSET_RAW_MEM;
351                 return pair->other_num;
352               }
353             }
354           }
355           /* Search another pair with same number of bytes used in std_heap */
356           previous_cursor = cursor - 1;
357           while(previous_cursor >= 0){
358             pair_test = (mc_pair_t)xbt_dynar_get_as(visited_pairs, previous_cursor, mc_pair_t);
359             bytes_used_test = pair_test->heap_bytes_used;
360             if(bytes_used_test != current_bytes_used)
361               break;
362             if(xbt_automaton_state_compare(pair_test->automaton_state, pair->automaton_state) == 0){
363               if(xbt_automaton_propositional_symbols_compare_value(pair_test->atomic_propositions, pair->atomic_propositions) == 0){  
364                 if(snapshot_compare(pair->graph_state->system_state, pair_test->graph_state->system_state) == 0){
365                   if(pair_test->other_num == -1)
366                     pair->other_num = pair_test->num;
367                   else
368                     pair->other_num = pair_test->other_num;
369                   if(dot_output == NULL)
370                     XBT_DEBUG("Pair %d already visited ! (equal to pair %d)", pair->num, pair_test->num);
371                   else
372                     XBT_DEBUG("Pair %d already visited ! (equal to pair %d (pair %d in dot_output))", pair->num, pair_test->num, pair->other_num);
373                   xbt_dynar_remove_at(visited_pairs, previous_cursor, NULL);
374                   xbt_dynar_insert_at(visited_pairs, previous_cursor, &pair);
375                   pair_test->visited_removed = 1;
376                   if(pair_test->stack_removed && pair_test->visited_removed){
377                     if((pair_test->automaton_state->type == 1) || (pair_test->automaton_state->type == 2)){
378                       if(pair_test->acceptance_removed){ 
379                         MC_pair_delete(pair_test);
380                       }
381                     }else{
382                       MC_pair_delete(pair_test);
383                     }     
384                   }
385                   if(raw_mem_set)
386                     MC_SET_RAW_MEM;
387                   else
388                     MC_UNSET_RAW_MEM;
389                   return pair->other_num;
390                 }
391               }
392             }
393             previous_cursor--;
394           }
395           next_cursor = cursor + 1;
396           while(next_cursor < xbt_dynar_length(visited_pairs)){
397             pair_test = (mc_pair_t)xbt_dynar_get_as(visited_pairs, next_cursor, mc_pair_t);
398             bytes_used_test = pair_test->heap_bytes_used;
399             if(bytes_used_test != current_bytes_used)
400               break;
401             if(xbt_automaton_state_compare(pair_test->automaton_state, pair->automaton_state) == 0){
402               if(xbt_automaton_propositional_symbols_compare_value(pair_test->atomic_propositions, pair->atomic_propositions) == 0){
403                 if(snapshot_compare(pair->graph_state->system_state, pair_test->graph_state->system_state) == 0){
404                   if(pair_test->other_num == -1)
405                     pair->other_num = pair_test->num;
406                   else
407                     pair->other_num = pair_test->other_num;
408                   if(dot_output == NULL)
409                     XBT_DEBUG("Pair %d already visited ! (equal to pair %d)", pair->num, pair_test->num);
410                   else
411                     XBT_DEBUG("Pair %d already visited ! (equal to pair %d (pair %d in dot_output))", pair->num, pair_test->num, pair->other_num);
412                   xbt_dynar_remove_at(visited_pairs, next_cursor, NULL);
413                   xbt_dynar_insert_at(visited_pairs, next_cursor, &pair);
414                   pair_test->visited_removed = 1;
415                   if(pair_test->stack_removed && pair_test->visited_removed){
416                     if((pair_test->automaton_state->type == 1) || (pair_test->automaton_state->type == 2)){
417                       if(pair_test->acceptance_removed){ 
418                         MC_pair_delete(pair_test);
419                       }
420                     }else{
421                       MC_pair_delete(pair_test);
422                     }     
423                   }
424                   if(raw_mem_set)
425                     MC_SET_RAW_MEM;
426                   else
427                     MC_UNSET_RAW_MEM;
428                   return pair->other_num;
429                 }
430               }
431             }
432             next_cursor++;
433           }
434         }
435       }
436     }
437
438     pair_test = (mc_pair_t)xbt_dynar_get_as(visited_pairs, cursor, mc_pair_t);
439     bytes_used_test = pair_test->heap_bytes_used;
440
441     if(bytes_used_test < current_bytes_used)
442       xbt_dynar_insert_at(visited_pairs, cursor + 1, &pair);
443     else
444       xbt_dynar_insert_at(visited_pairs, cursor, &pair);
445
446     if(xbt_dynar_length(visited_pairs) > _sg_mc_visited){
447       int min = mc_stats->expanded_states;
448       unsigned int cursor2 = 0;
449       unsigned int index = 0;
450       xbt_dynar_foreach(visited_pairs, cursor2, pair_test){
451         if(pair_test->num < min){
452           index = cursor2;
453           min = pair_test->num;
454         }
455       }
456       xbt_dynar_remove_at(visited_pairs, index, &pair_test);
457       pair_test->visited_removed = 1;
458       if(pair_test->stack_removed && pair_test->acceptance_removed && pair_test->visited_removed)
459         MC_pair_delete(pair_test);
460       
461     }
462
463     MC_UNSET_RAW_MEM;
464
465     if(raw_mem_set)
466       MC_SET_RAW_MEM;
467     
468     return -1;
469     
470   }
471  
472 }
473
474 static int MC_automaton_evaluate_label(xbt_automaton_exp_label_t l, xbt_dynar_t atomic_propositions_values){
475   
476   switch(l->type){
477   case 0 : {
478     int left_res = MC_automaton_evaluate_label(l->u.or_and.left_exp, atomic_propositions_values);
479     int right_res = MC_automaton_evaluate_label(l->u.or_and.right_exp, atomic_propositions_values);
480     return (left_res || right_res);
481   }
482   case 1 : {
483     int left_res = MC_automaton_evaluate_label(l->u.or_and.left_exp, atomic_propositions_values);
484     int right_res = MC_automaton_evaluate_label(l->u.or_and.right_exp, atomic_propositions_values);
485     return (left_res && right_res);
486   }
487   case 2 : {
488     int res = MC_automaton_evaluate_label(l->u.exp_not, atomic_propositions_values);
489     return (!res);
490   }
491   case 3 : { 
492     unsigned int cursor = 0;
493     xbt_automaton_propositional_symbol_t p = NULL;
494     xbt_dynar_foreach(_mc_property_automaton->propositional_symbols, cursor, p){
495       if(strcmp(p->pred, l->u.predicat) == 0)
496         return (int)xbt_dynar_get_as(atomic_propositions_values, cursor, int);
497     }
498     return -1;
499   }
500   case 4 : {
501     return 2;
502   }
503   default : 
504     return -1;
505   }
506 }
507
508
509 /********* DDFS Algorithm *********/
510
511
512 void MC_ddfs_init(void){
513
514   initial_state_liveness->raw_mem_set = (mmalloc_get_current_heap() == raw_heap);
515
516   XBT_DEBUG("**************************************************");
517   XBT_DEBUG("Double-DFS init");
518   XBT_DEBUG("**************************************************");
519
520   mc_pair_t initial_pair = NULL;
521   smx_process_t process; 
522
523   MC_wait_for_requests();
524
525   MC_SET_RAW_MEM;
526
527   acceptance_pairs = xbt_dynar_new(sizeof(mc_pair_t), NULL); 
528   visited_pairs = xbt_dynar_new(sizeof(mc_pair_t), NULL); 
529   successors = xbt_dynar_new(sizeof(mc_pair_t), NULL);
530
531   initial_state_liveness->snapshot = MC_take_snapshot();
532   initial_state_liveness->prev_pair = 0;
533
534   MC_UNSET_RAW_MEM; 
535   
536   unsigned int cursor = 0;
537   xbt_automaton_state_t automaton_state;
538
539   xbt_dynar_foreach(_mc_property_automaton->states, cursor, automaton_state){
540     if(automaton_state->type == -1){ /* Initial automaton state */
541       
542       MC_SET_RAW_MEM;
543
544       initial_pair = MC_pair_new();
545       initial_pair->automaton_state = automaton_state;
546       initial_pair->graph_state = MC_state_new();
547       initial_pair->atomic_propositions = get_atomic_propositions_values();
548
549       /* Get enabled process and insert it in the interleave set of the graph_state */
550       xbt_swag_foreach(process, simix_global->process_list){
551         if(MC_process_is_enabled(process)){
552           MC_state_interleave_process(initial_pair->graph_state, process);
553         }
554       }
555
556       initial_pair->requests = MC_state_interleave_size(initial_pair->graph_state);
557       initial_pair->search_cycle = 0;
558
559       xbt_fifo_unshift(mc_stack_liveness, initial_pair);
560
561       MC_UNSET_RAW_MEM;
562       
563       MC_ddfs();
564       
565       if(cursor != 0){
566         MC_restore_snapshot(initial_state_liveness->snapshot);
567         MC_UNSET_RAW_MEM;
568       }
569       
570
571     }else if(automaton_state->type == 2){ /* Acceptance automaton state */
572       
573       MC_SET_RAW_MEM;
574
575       initial_pair = MC_pair_new();
576       initial_pair->automaton_state = automaton_state;
577       initial_pair->graph_state = MC_state_new();
578       initial_pair->atomic_propositions = get_atomic_propositions_values();
579         
580       /* Get enabled process and insert it in the interleave set of the graph_state */
581       xbt_swag_foreach(process, simix_global->process_list){
582         if(MC_process_is_enabled(process)){
583           MC_state_interleave_process(initial_pair->graph_state, process);
584         }
585       }
586
587       initial_pair->requests = MC_state_interleave_size(initial_pair->graph_state);
588       initial_pair->search_cycle = 1;
589         
590       xbt_fifo_unshift(mc_stack_liveness, initial_pair);
591         
592       MC_UNSET_RAW_MEM;
593
594       set_acceptance_pair_reached(initial_pair);
595   
596       MC_ddfs();
597
598       if(cursor != 0){
599         MC_restore_snapshot(initial_state_liveness->snapshot);
600         MC_UNSET_RAW_MEM;
601       }
602     }
603   }
604
605   if(initial_state_liveness->raw_mem_set)
606     MC_SET_RAW_MEM;
607   else
608     MC_UNSET_RAW_MEM;
609   
610
611 }
612
613
614 void MC_ddfs(){
615
616   smx_process_t process;
617   mc_pair_t current_pair = NULL;
618
619   if(xbt_fifo_size(mc_stack_liveness) == 0)
620     return;
621
622   /* Get current pair */
623   current_pair = (mc_pair_t)xbt_fifo_get_item_content(xbt_fifo_get_first_item(mc_stack_liveness));
624
625   /* Update current state in buchi automaton */
626   _mc_property_automaton->current_state = current_pair->automaton_state;
627
628   XBT_DEBUG("********************* ( Depth = %d, search_cycle = %d )", xbt_fifo_size(mc_stack_liveness), current_pair->search_cycle);
629  
630   mc_stats->visited_pairs++;
631
632   int value;
633   smx_simcall_t req = NULL;
634   char *req_str;
635
636   xbt_automaton_transition_t transition_succ;
637   unsigned int cursor = 0;
638   int res;
639   int reached_num, visited_num;
640
641   mc_pair_t next_pair = NULL;
642   xbt_dynar_t prop_values = NULL;
643   
644   if(xbt_fifo_size(mc_stack_liveness) < _sg_mc_max_depth){
645
646     if(current_pair->requests > 0){
647
648       if(current_pair->search_cycle){
649
650         if((current_pair->automaton_state->type == 1) || (current_pair->automaton_state->type == 2)){ 
651           
652           if((reached_num = is_reached_acceptance_pair(current_pair)) != -1){
653         
654             XBT_INFO("Pair %d already reached (equal to pair %d) !", current_pair->num, reached_num);
655             
656             MC_SET_RAW_MEM;
657             xbt_fifo_shift(mc_stack_liveness);
658             if(dot_output != NULL)
659               fprintf(dot_output, "\"%d\" -> \"%d\" [%s];\n", initial_state_liveness->prev_pair, reached_num, initial_state_liveness->prev_req);
660             MC_UNSET_RAW_MEM;
661
662             XBT_INFO("*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*");
663             XBT_INFO("|             ACCEPTANCE CYCLE            |");
664             XBT_INFO("*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*");
665             XBT_INFO("Counter-example that violates formula :");
666             MC_show_stack_liveness(mc_stack_liveness);
667             MC_dump_stack_liveness(mc_stack_liveness);
668             MC_print_statistics(mc_stats);
669             xbt_abort();
670
671           }
672         }
673       }
674
675       if((visited_num = is_visited_pair(current_pair)) != -1){
676
677         MC_SET_RAW_MEM;
678         if(dot_output != NULL)
679           fprintf(dot_output, "\"%d\" -> \"%d\" [%s];\n", initial_state_liveness->prev_pair, visited_num, initial_state_liveness->prev_req);
680         MC_UNSET_RAW_MEM;
681         
682       
683       }else{  
684
685         while((req = MC_state_get_request(current_pair->graph_state, &value)) != NULL){
686
687           MC_SET_RAW_MEM;
688           if(dot_output != NULL){
689             if(initial_state_liveness->prev_pair != 0 && initial_state_liveness->prev_pair != current_pair->num){
690               fprintf(dot_output, "\"%d\" -> \"%d\" [%s];\n", initial_state_liveness->prev_pair, current_pair->num, initial_state_liveness->prev_req);
691               xbt_free(initial_state_liveness->prev_req);
692             }
693             initial_state_liveness->prev_pair = current_pair->num;
694           }
695           MC_UNSET_RAW_MEM;
696
697           /* Debug information */
698           if(XBT_LOG_ISENABLED(mc_liveness, xbt_log_priority_debug)){
699             req_str = MC_request_to_string(req, value);
700             XBT_DEBUG("Execute: %s", req_str);
701             xbt_free(req_str);
702           }
703
704           MC_SET_RAW_MEM;
705           if(dot_output != NULL){
706             initial_state_liveness->prev_req = MC_request_get_dot_output(req, value);
707             if(current_pair->search_cycle)
708               fprintf(dot_output, "%d [shape=doublecircle];\n", current_pair->num);
709           }
710           MC_UNSET_RAW_MEM; 
711           
712           MC_state_set_executed_request(current_pair->graph_state, req, value);  
713           mc_stats->executed_transitions++;
714
715           /* Answer the request */
716           SIMIX_simcall_pre(req, value);
717           
718           /* Wait for requests (schedules processes) */
719           MC_wait_for_requests();
720
721           MC_SET_RAW_MEM;
722           prop_values = get_atomic_propositions_values();
723           MC_UNSET_RAW_MEM;
724          
725           /* Evaluate enabled transition according to atomic propositions values */
726           cursor= 0;
727           xbt_dynar_foreach(current_pair->automaton_state->out, cursor, transition_succ){
728
729             res = MC_automaton_evaluate_label(transition_succ->label, prop_values);
730
731             if(res == 1){ // enabled transition in automaton
732
733               MC_SET_RAW_MEM;
734
735               next_pair = MC_pair_new();
736               next_pair->graph_state = MC_state_new();
737               next_pair->automaton_state = transition_succ->dst;
738               next_pair->atomic_propositions = get_atomic_propositions_values();
739
740               /* Get enabled process and insert it in the interleave set of the next graph_state */
741               xbt_swag_foreach(process, simix_global->process_list){
742                 if(MC_process_is_enabled(process)){
743                   MC_state_interleave_process(next_pair->graph_state, process);
744                 }
745               }
746
747               next_pair->requests = MC_state_interleave_size(next_pair->graph_state);
748               
749               if(next_pair->automaton_state->type == 1 || next_pair->automaton_state->type == 2 || current_pair->search_cycle)
750                 next_pair->search_cycle = 1;
751             
752               xbt_fifo_unshift(mc_stack_liveness, next_pair);
753
754               if(mc_stats->expanded_pairs%1000000 == 0)
755                 XBT_INFO("Expanded pairs : %lu", mc_stats->expanded_pairs);
756
757               MC_UNSET_RAW_MEM;
758
759               MC_ddfs();
760
761             }
762
763           }
764
765           /* Then, evaluate true transitions (always true, whatever atomic propositions values) */
766           cursor = 0;   
767           xbt_dynar_foreach(current_pair->automaton_state->out, cursor, transition_succ){
768       
769             res = MC_automaton_evaluate_label(transition_succ->label, prop_values);
770   
771             if(res == 2){ // true transition in automaton
772             
773               MC_SET_RAW_MEM;
774             
775               next_pair = MC_pair_new();
776               next_pair->graph_state = MC_state_new();
777               next_pair->automaton_state = transition_succ->dst;
778               next_pair->atomic_propositions = get_atomic_propositions_values();
779
780               /* Get enabled process and insert it in the interleave set of the next graph_state */
781               xbt_swag_foreach(process, simix_global->process_list){
782                 if(MC_process_is_enabled(process)){
783                   MC_state_interleave_process(next_pair->graph_state, process);
784                 }
785               }
786
787               next_pair->requests = MC_state_interleave_size(next_pair->graph_state);
788             
789               if(next_pair->automaton_state->type == 1 || next_pair->automaton_state->type == 2 || current_pair->search_cycle)
790                 next_pair->search_cycle = 1;
791
792               xbt_fifo_unshift(mc_stack_liveness, next_pair);
793
794               if(mc_stats->expanded_pairs%1000000 == 0)
795                 XBT_INFO("Expanded pairs : %lu", mc_stats->expanded_pairs);
796             
797               MC_UNSET_RAW_MEM;
798
799               MC_ddfs();
800
801             }
802
803           }
804
805           if(MC_state_interleave_size(current_pair->graph_state) > 0){
806             XBT_DEBUG("Backtracking to depth %d", xbt_fifo_size(mc_stack_liveness));
807             MC_replay_liveness(mc_stack_liveness, 0);
808           }
809         
810         }
811
812       }
813  
814     }else{
815
816       mc_stats->executed_transitions++;
817       
818       XBT_DEBUG("No request to execute in this state, search evolution in B├╝chi Automaton.");
819
820       if(current_pair->search_cycle){
821
822         if((current_pair->automaton_state->type == 1) || (current_pair->automaton_state->type == 2)){ 
823           
824           if((reached_num = is_reached_acceptance_pair(current_pair)) != -1){
825         
826             XBT_INFO("Pair %d already reached (equal to pair %d) !", current_pair->num, reached_num);
827             
828             MC_SET_RAW_MEM;
829             xbt_fifo_shift(mc_stack_liveness);
830             MC_UNSET_RAW_MEM;
831
832             XBT_INFO("*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*");
833             XBT_INFO("|             ACCEPTANCE CYCLE            |");
834             XBT_INFO("*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*");
835             XBT_INFO("Counter-example that violates formula :");
836             MC_show_stack_liveness(mc_stack_liveness);
837             MC_dump_stack_liveness(mc_stack_liveness);
838             MC_print_statistics(mc_stats);
839             xbt_abort();
840
841           }
842         }
843       }
844
845       if((visited_num = is_visited_pair(current_pair)) != -1){
846
847         XBT_DEBUG("Pair %d already visited ! (equal to pair %d)", current_pair->num, visited_num);
848       
849       }else{            
850         
851         MC_SET_RAW_MEM;
852         prop_values = get_atomic_propositions_values();
853         MC_UNSET_RAW_MEM;
854
855         /* Evaluate enabled transition according to atomic propositions values */
856         cursor= 0;
857         xbt_dynar_foreach(current_pair->automaton_state->out, cursor, transition_succ){
858
859           res = MC_automaton_evaluate_label(transition_succ->label, prop_values);
860
861           if(res == 1){ // enabled transition in automaton
862
863             MC_SET_RAW_MEM;
864
865             next_pair = MC_pair_new();
866             next_pair->graph_state = MC_state_new();
867             next_pair->automaton_state = transition_succ->dst;
868             next_pair->atomic_propositions = get_atomic_propositions_values();
869             next_pair->requests = MC_state_interleave_size(next_pair->graph_state);
870               
871             if(next_pair->automaton_state->type == 1 || next_pair->automaton_state->type == 2 || current_pair->search_cycle)
872               next_pair->search_cycle = 1;
873             
874             xbt_fifo_unshift(mc_stack_liveness, next_pair);
875
876             if(mc_stats->expanded_pairs%1000 == 0)
877               XBT_INFO("Expanded pairs : %lu", mc_stats->expanded_pairs);
878
879             if(dot_output != NULL)
880               fprintf(dot_output, "\"%d\" -> \"%d\" [%s];\n", current_pair->num, next_pair->num, "");
881
882             MC_UNSET_RAW_MEM;
883
884             MC_ddfs();
885
886           }
887
888         }
889
890         /* Then, evaluate true transitions (always true, whatever atomic propositions values) */
891         cursor = 0;   
892         xbt_dynar_foreach(current_pair->automaton_state->out, cursor, transition_succ){
893       
894           res = MC_automaton_evaluate_label(transition_succ->label, prop_values);
895   
896           if(res == 2){ // true transition in automaton
897
898             MC_SET_RAW_MEM;
899             
900             next_pair = MC_pair_new();
901             next_pair->graph_state = MC_state_new();
902             next_pair->automaton_state = transition_succ->dst;
903             next_pair->atomic_propositions = get_atomic_propositions_values();
904             next_pair->requests = MC_state_interleave_size(next_pair->graph_state);
905             
906             if(next_pair->automaton_state->type == 1 || next_pair->automaton_state->type == 2 || current_pair->search_cycle)
907               next_pair->search_cycle = 1;
908
909             xbt_fifo_unshift(mc_stack_liveness, next_pair);
910
911             if(mc_stats->expanded_pairs%1000 == 0)
912               XBT_INFO("Expanded pairs : %lu", mc_stats->expanded_pairs);
913             
914             if(dot_output != NULL)
915               fprintf(dot_output, "\"%d\" -> \"%d\" [%s];\n", current_pair->num, next_pair->num, "");
916
917             MC_UNSET_RAW_MEM;
918
919             MC_ddfs();
920
921           }
922
923         }
924       }
925     }
926     
927   }else{
928     
929     XBT_WARN("/!\\ Max depth reached ! /!\\ ");
930     if(MC_state_interleave_size(current_pair->graph_state) > 0){
931       XBT_WARN("/!\\ But, there are still processes to interleave. Model-checker will not be able to ensure the soundness of the verification from now. /!\\ "); 
932       if(_sg_mc_max_depth == 1000)
933         XBT_WARN("Notice : the default value of max depth is 1000 but you can change it with cfg=model-check/max_depth:value.");
934     }
935     
936   }
937
938   if(xbt_fifo_size(mc_stack_liveness) == _sg_mc_max_depth ){
939     XBT_DEBUG("Pair %d (depth = %d) shifted in stack, maximum depth reached", current_pair->num, xbt_fifo_size(mc_stack_liveness) );
940   }else{
941     XBT_DEBUG("Pair %d (depth = %d) shifted in stack", current_pair->num, xbt_fifo_size(mc_stack_liveness) );
942   }
943
944   
945   MC_SET_RAW_MEM;
946   xbt_dynar_free(&prop_values);
947   current_pair = xbt_fifo_shift(mc_stack_liveness);
948   current_pair->stack_removed = 1;
949   if(current_pair->search_cycle){
950     remove_acceptance_pair(current_pair);
951   }else{
952     if(_sg_mc_visited == 0)
953       MC_pair_delete(current_pair);
954     else if(current_pair->visited_removed)
955       MC_pair_delete(current_pair);
956   }
957
958   MC_UNSET_RAW_MEM;
959
960 }