/********* Global variables *********/
xbt_dynar_t acceptance_pairs;
-xbt_dynar_t successors;
xbt_parmap_t parmap;
/********* Static functions *********/
}
-static mc_visited_pair_t is_reached_acceptance_pair(int pair_num,
- xbt_automaton_state_t
- automaton_state,
- xbt_dynar_t
- atomic_propositions)
-{
+static mc_visited_pair_t is_reached_acceptance_pair(mc_pair_t pair){
int raw_mem_set = (mmalloc_get_current_heap() == mc_heap);
MC_SET_MC_HEAP;
- mc_visited_pair_t pair = NULL;
- pair = MC_visited_pair_new(pair_num, automaton_state, atomic_propositions);
- pair->acceptance_pair = 1;
+ mc_visited_pair_t new_pair = NULL;
+ new_pair = MC_visited_pair_new(pair->num, pair->automaton_state, pair->atomic_propositions, pair->graph_state->system_state);
+ new_pair->acceptance_pair = 1;
if (xbt_dynar_is_empty(acceptance_pairs)) {
- xbt_dynar_push(acceptance_pairs, &pair);
+ xbt_dynar_push(acceptance_pairs, &new_pair);
} else {
mc_visited_pair_t pair_test;
int cursor;
- index = get_search_interval(acceptance_pairs, pair, &min, &max);
+ index = get_search_interval(acceptance_pairs, new_pair, &min, &max);
if (min != -1 && max != -1) { // Acceptance pair with same number of processes and same heap bytes used exists
} */
cursor = min;
- while (cursor <= max) {
- pair_test =
- (mc_visited_pair_t) xbt_dynar_get_as(acceptance_pairs, cursor,
- mc_visited_pair_t);
- if (xbt_automaton_state_compare
- (pair_test->automaton_state, pair->automaton_state) == 0) {
- if (xbt_automaton_propositional_symbols_compare_value
- (pair_test->atomic_propositions,
- pair->atomic_propositions) == 0) {
- if (snapshot_compare(pair_test, pair) == 0) {
- XBT_INFO("Pair %d already reached (equal to pair %d) !",
- pair->num, pair_test->num);
-
- xbt_fifo_shift(mc_stack);
- if (dot_output != NULL)
- fprintf(dot_output, "\"%d\" -> \"%d\" [%s];\n",
- initial_global_state->prev_pair, pair_test->num,
- initial_global_state->prev_req);
-
- if (!raw_mem_set)
- MC_SET_STD_HEAP;
-
- return NULL;
+ if(pair->search_cycle == 1){
+ while (cursor <= max) {
+ pair_test = (mc_visited_pair_t) xbt_dynar_get_as(acceptance_pairs, cursor, mc_visited_pair_t);
+ if (xbt_automaton_state_compare(pair_test->automaton_state, new_pair->automaton_state) == 0) {
+ if (xbt_automaton_propositional_symbols_compare_value(pair_test->atomic_propositions, new_pair->atomic_propositions) == 0) {
+ if (snapshot_compare(pair_test, new_pair) == 0) {
+ XBT_INFO("Pair %d already reached (equal to pair %d) !", new_pair->num, pair_test->num);
+ xbt_fifo_shift(mc_stack);
+ if (dot_output != NULL)
+ fprintf(dot_output, "\"%d\" -> \"%d\" [%s];\n", initial_global_state->prev_pair, pair_test->num, initial_global_state->prev_req);
+
+ if (!raw_mem_set)
+ MC_SET_STD_HEAP;
+
+ return NULL;
+ }
}
}
+ cursor++;
}
- cursor++;
}
- xbt_dynar_insert_at(acceptance_pairs, min, &pair);
+ xbt_dynar_insert_at(acceptance_pairs, min, &new_pair);
} else {
- pair_test =
- (mc_visited_pair_t) xbt_dynar_get_as(acceptance_pairs, index,
- mc_visited_pair_t);
- if (pair_test->nb_processes < pair->nb_processes) {
- xbt_dynar_insert_at(acceptance_pairs, index + 1, &pair);
+ pair_test = (mc_visited_pair_t) xbt_dynar_get_as(acceptance_pairs, index, mc_visited_pair_t);
+ if (pair_test->nb_processes < new_pair->nb_processes) {
+ xbt_dynar_insert_at(acceptance_pairs, index + 1, &new_pair);
} else {
- if (pair_test->heap_bytes_used < pair->heap_bytes_used)
- xbt_dynar_insert_at(acceptance_pairs, index + 1, &pair);
+ if (pair_test->heap_bytes_used < new_pair->heap_bytes_used)
+ xbt_dynar_insert_at(acceptance_pairs, index + 1, &new_pair);
else
- xbt_dynar_insert_at(acceptance_pairs, index, &pair);
+ xbt_dynar_insert_at(acceptance_pairs, index, &new_pair);
}
}
if (!raw_mem_set)
MC_SET_STD_HEAP;
- return pair;
+ return new_pair;
}
-static void remove_acceptance_pair(int pair_num)
-{
+static void remove_acceptance_pair(int pair_num) {
int raw_mem_set = (mmalloc_get_current_heap() == mc_heap);
unsigned int cursor = 0;
mc_visited_pair_t pair_test = NULL;
+ int pair_found = 0;
xbt_dynar_foreach(acceptance_pairs, cursor, pair_test) {
if (pair_test->num == pair_num) {
+ pair_found = 1;
break;
}
}
- xbt_dynar_remove_at(acceptance_pairs, cursor, &pair_test);
+ if(pair_found == 1) {
+ xbt_dynar_remove_at(acceptance_pairs, cursor, &pair_test);
- pair_test->acceptance_removed = 1;
+ pair_test->acceptance_removed = 1;
+
+ if (_sg_mc_visited == 0 || pair_test->visited_removed == 1)
+ MC_visited_pair_delete(pair_test);
- if (_sg_mc_visited == 0) {
- MC_visited_pair_delete(pair_test);
- } else if (pair_test->visited_removed == 1) {
- MC_visited_pair_delete(pair_test);
}
if (!raw_mem_set)
switch (l->type) {
case 0:{
- int left_res =
- MC_automaton_evaluate_label(l->u.or_and.left_exp,
- atomic_propositions_values);
- int right_res =
- MC_automaton_evaluate_label(l->u.or_and.right_exp,
- atomic_propositions_values);
+ int left_res = MC_automaton_evaluate_label(l->u.or_and.left_exp, atomic_propositions_values);
+ int right_res = MC_automaton_evaluate_label(l->u.or_and.right_exp, atomic_propositions_values);
return (left_res || right_res);
}
case 1:{
- int left_res =
- MC_automaton_evaluate_label(l->u.or_and.left_exp,
- atomic_propositions_values);
- int right_res =
- MC_automaton_evaluate_label(l->u.or_and.right_exp,
- atomic_propositions_values);
+ int left_res = MC_automaton_evaluate_label(l->u.or_and.left_exp, atomic_propositions_values);
+ int right_res = MC_automaton_evaluate_label(l->u.or_and.right_exp, atomic_propositions_values);
return (left_res && right_res);
}
case 2:{
- int res =
- MC_automaton_evaluate_label(l->u.exp_not, atomic_propositions_values);
+ int res = MC_automaton_evaluate_label(l->u.exp_not, atomic_propositions_values);
return (!res);
}
case 3:{
unsigned int cursor = 0;
xbt_automaton_propositional_symbol_t p = NULL;
- xbt_dynar_foreach(_mc_property_automaton->propositional_symbols, cursor,
- p) {
+ xbt_dynar_foreach(_mc_property_automaton->propositional_symbols, cursor, p) {
if (strcmp(p->pred, l->u.predicat) == 0)
- return (int) xbt_dynar_get_as(atomic_propositions_values, cursor,
- int);
+ return (int) xbt_dynar_get_as(atomic_propositions_values, cursor, int);
}
return -1;
}
}
}
-void MC_pre_modelcheck_liveness(void)
-{
+void MC_pre_modelcheck_liveness(void) {
initial_global_state->raw_mem_set = (mmalloc_get_current_heap() == mc_heap);
MC_SET_MC_HEAP;
acceptance_pairs = xbt_dynar_new(sizeof(mc_visited_pair_t), NULL);
- visited_pairs = xbt_dynar_new(sizeof(mc_visited_pair_t), NULL);
- successors = xbt_dynar_new(sizeof(mc_pair_t), NULL);
+ if(_sg_mc_visited > 0)
+ visited_pairs = xbt_dynar_new(sizeof(mc_visited_pair_t), NULL);
initial_global_state->snapshot = MC_take_snapshot(0);
initial_global_state->prev_pair = 0;
- MC_SET_STD_HEAP;
-
unsigned int cursor = 0;
xbt_automaton_state_t automaton_state;
-
+
xbt_dynar_foreach(_mc_property_automaton->states, cursor, automaton_state) {
if (automaton_state->type == -1) { /* Initial automaton state */
- MC_SET_MC_HEAP;
-
initial_pair = MC_pair_new();
initial_pair->automaton_state = automaton_state;
initial_pair->graph_state = MC_state_new();
initial_pair->atomic_propositions = get_atomic_propositions_values();
+ initial_pair->depth = 1;
/* Get enabled processes and insert them in the interleave set of the graph_state */
xbt_swag_foreach(process, simix_global->process_list) {
}
}
- initial_pair->requests =
- MC_state_interleave_size(initial_pair->graph_state);
+ initial_pair->requests = MC_state_interleave_size(initial_pair->graph_state);
initial_pair->search_cycle = 0;
xbt_fifo_unshift(mc_stack, initial_pair);
-
- MC_SET_STD_HEAP;
-
- MC_modelcheck_liveness();
-
- if (cursor != 0) {
- MC_restore_snapshot(initial_global_state->snapshot);
- MC_SET_STD_HEAP;
- }
}
}
+ MC_SET_STD_HEAP;
+
+ MC_modelcheck_liveness();
+
if (initial_global_state->raw_mem_set)
MC_SET_MC_HEAP;
- else
- MC_SET_STD_HEAP;
}
+void MC_modelcheck_liveness() {
-void MC_modelcheck_liveness()
-{
-
- smx_process_t process;
+ smx_process_t process = NULL;
mc_pair_t current_pair = NULL;
-
- if (xbt_fifo_size(mc_stack) == 0)
- return;
-
- /* Get current pair */
- current_pair =
- (mc_pair_t) xbt_fifo_get_item_content(xbt_fifo_get_first_item(mc_stack));
-
- /* Update current state in buchi automaton */
- _mc_property_automaton->current_state = current_pair->automaton_state;
-
- XBT_DEBUG
- ("********************* ( Depth = %d, search_cycle = %d, interleave size %d, pair_num %d)",
- xbt_fifo_size(mc_stack), current_pair->search_cycle,
- MC_state_interleave_size(current_pair->graph_state), current_pair->num);
-
- mc_stats->visited_pairs++;
-
- int value;
+ int value, res, visited_num = -1;
smx_simcall_t req = NULL;
-
- xbt_automaton_transition_t transition_succ;
- unsigned int cursor = 0;
- int res;
- int visited_num;
-
+ xbt_automaton_transition_t transition_succ = NULL;
+ int cursor = 0;
mc_pair_t next_pair = NULL;
xbt_dynar_t prop_values = NULL;
mc_visited_pair_t reached_pair = NULL;
- int counter_example_depth = 0;
+
+ while(xbt_fifo_size(mc_stack) > 0){
- if (xbt_fifo_size(mc_stack) < _sg_mc_max_depth) {
+ /* Get current pair */
+ current_pair = (mc_pair_t) xbt_fifo_get_item_content(xbt_fifo_get_first_item(mc_stack));
- if (current_pair->requests > 0) {
+ /* Update current state in buchi automaton */
+ _mc_property_automaton->current_state = current_pair->automaton_state;
- if (current_pair->search_cycle) {
-
- if ((current_pair->automaton_state->type == 1)
- || (current_pair->automaton_state->type == 2)) {
- if ((reached_pair =
- is_reached_acceptance_pair(current_pair->num,
- current_pair->automaton_state,
- current_pair->atomic_propositions)) ==
- NULL) {
-
- counter_example_depth = xbt_fifo_size(mc_stack);
- XBT_INFO("*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*");
- XBT_INFO("| ACCEPTANCE CYCLE |");
- XBT_INFO("*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*");
- XBT_INFO("Counter-example that violates formula :");
- MC_show_stack_liveness(mc_stack);
- MC_dump_stack_liveness(mc_stack);
- MC_print_statistics(mc_stats);
- XBT_INFO("Counter-example depth : %d", counter_example_depth);
- xbt_abort();
+ XBT_DEBUG("********************* ( Depth = %d, search_cycle = %d, interleave size %d, pair_num %d)",
+ current_pair->depth, current_pair->search_cycle,
+ MC_state_interleave_size(current_pair->graph_state), current_pair->num);
- }
+ if (current_pair->requests > 0) {
+
+ if (current_pair->automaton_state->type == 1 && current_pair->exploration_started == 0) {
+ /* If new acceptance pair, return new pair */
+ if ((reached_pair = is_reached_acceptance_pair(current_pair)) == NULL) {
+ int counter_example_depth = current_pair->depth;
+ XBT_INFO("*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*");
+ XBT_INFO("| ACCEPTANCE CYCLE |");
+ XBT_INFO("*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*");
+ XBT_INFO("Counter-example that violates formula :");
+ MC_show_stack_liveness(mc_stack);
+ MC_dump_stack_liveness(mc_stack);
+ MC_print_statistics(mc_stats);
+ XBT_INFO("Counter-example depth : %d", counter_example_depth);
+ xbt_abort();
}
}
- if ((visited_num =
- is_visited_pair(reached_pair, current_pair->num,
- current_pair->automaton_state,
- current_pair->atomic_propositions)) != -1) {
-
- MC_SET_MC_HEAP;
- if (dot_output != NULL)
- fprintf(dot_output, "\"%d\" -> \"%d\" [%s];\n",
- initial_global_state->prev_pair, visited_num,
- initial_global_state->prev_req);
- MC_SET_STD_HEAP;
-
- } else {
-
- while ((req =
- MC_state_get_request(current_pair->graph_state,
- &value)) != NULL) {
-
- MC_SET_MC_HEAP;
- if (dot_output != NULL) {
- if (initial_global_state->prev_pair != 0
- && initial_global_state->prev_pair != current_pair->num) {
- fprintf(dot_output, "\"%d\" -> \"%d\" [%s];\n",
- initial_global_state->prev_pair, current_pair->num,
- initial_global_state->prev_req);
- xbt_free(initial_global_state->prev_req);
- }
- initial_global_state->prev_pair = current_pair->num;
- }
- MC_SET_STD_HEAP;
-
- MC_LOG_REQUEST(mc_liveness, req, value);
-
- MC_SET_MC_HEAP;
- if (dot_output != NULL) {
- initial_global_state->prev_req =
- MC_request_get_dot_output(req, value);
- if (current_pair->search_cycle)
- fprintf(dot_output, "%d [shape=doublecircle];\n",
- current_pair->num);
- }
- MC_SET_STD_HEAP;
-
- MC_state_set_executed_request(current_pair->graph_state, req, value);
- mc_stats->executed_transitions++;
-
- /* Answer the request */
- SIMIX_simcall_handle(req, value);
-
- /* Wait for requests (schedules processes) */
- MC_wait_for_requests();
+ /* Pair already visited ? stop the exploration on the current path */
+ if ((current_pair->exploration_started == 0) && (visited_num = is_visited_pair(reached_pair, current_pair)) != -1) {
+ if (dot_output != NULL){
MC_SET_MC_HEAP;
- prop_values = get_atomic_propositions_values();
+ fprintf(dot_output, "\"%d\" -> \"%d\" [%s];\n", initial_global_state->prev_pair, visited_num, initial_global_state->prev_req);
+ fflush(dot_output);
MC_SET_STD_HEAP;
+ }
- int new_pair = 0;
-
- /* Evaluate enabled transition according to atomic propositions values */
- cursor = 0;
- xbt_dynar_foreach(current_pair->automaton_state->out, cursor,
- transition_succ) {
-
- res =
- MC_automaton_evaluate_label(transition_succ->label,
- prop_values);
-
- if (res == 1) { // enabled transition in automaton
-
- if (new_pair)
- MC_replay_liveness(mc_stack, 1);
-
- MC_SET_MC_HEAP;
-
+ XBT_DEBUG("Pair already visited (equal to pair %d), exploration on the current path stopped.", visited_num);
+ MC_SET_MC_HEAP;
+ current_pair->requests = 0;
+ MC_SET_STD_HEAP;
+ goto backtracking;
+
+ }else{
+
+ req = MC_state_get_request(current_pair->graph_state, &value);
+
+ if (dot_output != NULL) {
+ MC_SET_MC_HEAP;
+ if (initial_global_state->prev_pair != 0 && initial_global_state->prev_pair != current_pair->num) {
+ fprintf(dot_output, "\"%d\" -> \"%d\" [%s];\n", initial_global_state->prev_pair, current_pair->num, initial_global_state->prev_req);
+ xbt_free(initial_global_state->prev_req);
+ }
+ initial_global_state->prev_pair = current_pair->num;
+ initial_global_state->prev_req = MC_request_get_dot_output(req, value);
+ if (current_pair->search_cycle)
+ fprintf(dot_output, "%d [shape=doublecircle];\n", current_pair->num);
+ fflush(dot_output);
+ MC_SET_STD_HEAP;
+ }
+
+ char* req_str = MC_request_to_string(req, value);
+ XBT_DEBUG("Execute: %s", req_str);
+ xbt_free(req_str);
+
+ /* Set request as executed */
+ MC_state_set_executed_request(current_pair->graph_state, req, value);
+
+ /* Update mc_stats */
+ mc_stats->executed_transitions++;
+ if(current_pair->exploration_started == 0)
+ mc_stats->visited_pairs++;
+
+ /* Answer the request */
+ SIMIX_simcall_handle(req, value);
+
+ /* Wait for requests (schedules processes) */
+ MC_wait_for_requests();
+
+ MC_SET_MC_HEAP;
+
+ current_pair->requests--;
+ current_pair->exploration_started = 1;
+
+ /* Get values of atomic propositions (variables used in the property formula) */
+ prop_values = get_atomic_propositions_values();
+
+ /* Evaluate enabled/true transitions in automaton according to atomic propositions values and create new pairs */
+ cursor = xbt_dynar_length(current_pair->automaton_state->out) - 1;
+ while (cursor >= 0) {
+ transition_succ = (xbt_automaton_transition_t)xbt_dynar_get_as(current_pair->automaton_state->out, cursor, xbt_automaton_transition_t);
+ res = MC_automaton_evaluate_label(transition_succ->label, prop_values);
+ if (res == 1 || res == 2) { /* 1 = True transition (always enabled), 2 = enabled transition according to atomic prop values */
next_pair = MC_pair_new();
next_pair->graph_state = MC_state_new();
next_pair->automaton_state = transition_succ->dst;
next_pair->atomic_propositions = get_atomic_propositions_values();
-
+ next_pair->depth = current_pair->depth + 1;
/* Get enabled processes and insert them in the interleave set of the next graph_state */
xbt_swag_foreach(process, simix_global->process_list) {
if (MC_process_is_enabled(process)) {
}
}
- next_pair->requests =
- MC_state_interleave_size(next_pair->graph_state);
+ next_pair->requests = MC_state_interleave_size(next_pair->graph_state);
- if (next_pair->automaton_state->type == 1
- || next_pair->automaton_state->type == 2
- || current_pair->search_cycle)
+ /* FIXME : get search_cycle value for each acceptant state */
+ if (next_pair->automaton_state->type == 1 || current_pair->search_cycle)
next_pair->search_cycle = 1;
+ /* Add new pair to the exploration stack */
xbt_fifo_unshift(mc_stack, next_pair);
- if (mc_stats->expanded_pairs % 1000000 == 0)
- XBT_INFO("Expanded pairs : %lu", mc_stats->expanded_pairs);
-
- MC_SET_STD_HEAP;
-
- new_pair = 1;
-
- MC_modelcheck_liveness();
-
- }
-
- }
-
- /* Then, evaluate true transitions (always true, whatever atomic propositions values) */
- cursor = 0;
- xbt_dynar_foreach(current_pair->automaton_state->out, cursor,
- transition_succ) {
-
- res =
- MC_automaton_evaluate_label(transition_succ->label,
- prop_values);
-
- if (res == 2) { // true transition in automaton
-
- if (new_pair)
- MC_replay_liveness(mc_stack, 1);
-
- MC_SET_MC_HEAP;
-
- next_pair = MC_pair_new();
- next_pair->graph_state = MC_state_new();
- next_pair->automaton_state = transition_succ->dst;
- next_pair->atomic_propositions = get_atomic_propositions_values();
-
- /* Get enabled process and insert it in the interleave set of the next graph_state */
- xbt_swag_foreach(process, simix_global->process_list) {
- if (MC_process_is_enabled(process)) {
- MC_state_interleave_process(next_pair->graph_state, process);
- }
- }
-
- next_pair->requests =
- MC_state_interleave_size(next_pair->graph_state);
-
- if (next_pair->automaton_state->type == 1
- || next_pair->automaton_state->type == 2
- || current_pair->search_cycle)
- next_pair->search_cycle = 1;
-
- xbt_fifo_unshift(mc_stack, next_pair);
-
- if (mc_stats->expanded_pairs % 1000000 == 0)
- XBT_INFO("Expanded pairs : %lu", mc_stats->expanded_pairs);
-
- MC_SET_STD_HEAP;
-
- new_pair = 1;
-
- MC_modelcheck_liveness();
-
- }
-
- }
-
- if (MC_state_interleave_size(current_pair->graph_state) > 0) {
- XBT_DEBUG("Backtracking to depth %d", xbt_fifo_size(mc_stack));
- MC_replay_liveness(mc_stack, 0);
- }
+ }
+ cursor--;
+ }
+
+ MC_SET_STD_HEAP;
+
+ } /* End of visited_pair test */
+
+ } else {
+ backtracking:
+ if(visited_num == -1)
+ XBT_DEBUG("No more request to execute. Looking for backtracking point.");
+
+ MC_SET_MC_HEAP;
+
+ xbt_dynar_free(&prop_values);
+
+ /* Traverse the stack backwards until a pair with a non empty interleave
+ set is found, deleting all the pairs that have it empty in the way. */
+ while ((current_pair = xbt_fifo_shift(mc_stack)) != NULL) {
+ if (current_pair->requests > 0) {
+ /* We found a backtracking point */
+ XBT_DEBUG("Backtracking to depth %d", current_pair->depth);
+ xbt_fifo_unshift(mc_stack, current_pair);
+ MC_SET_STD_HEAP;
+ MC_replay_liveness(mc_stack);
+ XBT_DEBUG("Backtracking done");
+ break;
+ }else{
+ /* Delete pair */
+ XBT_DEBUG("Delete pair %d at depth %d", current_pair->num, current_pair->depth);
+ if (current_pair->automaton_state->type == 1)
+ remove_acceptance_pair(current_pair->num);
+ MC_pair_delete(current_pair);
}
-
}
-
- }
-
- } else {
-
- XBT_WARN("/!\\ Max depth reached ! /!\\ ");
- if (MC_state_interleave_size(current_pair->graph_state) > 0) {
- XBT_WARN
- ("/!\\ But, there are still processes to interleave. Model-checker will not be able to ensure the soundness of the verification from now. /!\\ ");
- if (_sg_mc_max_depth == 1000)
- XBT_WARN
- ("Notice : the default value of max depth is 1000 but you can change it with cfg=model-check/max_depth:value.");
- }
-
- }
-
- if (xbt_fifo_size(mc_stack) == _sg_mc_max_depth) {
- XBT_DEBUG("Pair %d (depth = %d) shifted in stack, maximum depth reached",
- current_pair->num, xbt_fifo_size(mc_stack));
- } else {
- XBT_DEBUG("Pair %d (depth = %d) shifted in stack", current_pair->num,
- xbt_fifo_size(mc_stack));
- }
-
-
- MC_SET_MC_HEAP;
- xbt_dynar_free(&prop_values);
- current_pair = xbt_fifo_shift(mc_stack);
- if (xbt_fifo_size(mc_stack) != _sg_mc_max_depth - 1
- && current_pair->requests > 0 && current_pair->search_cycle) {
- remove_acceptance_pair(current_pair->num);
- }
- MC_pair_delete(current_pair);
-
- MC_SET_STD_HEAP;
-
+
+ MC_SET_STD_HEAP;
+ } /* End of if (current_pair->requests > 0) else ... */
+
+ } /* End of while(xbt_fifo_size(mc_stack) > 0) */
+
}
