X-Git-Url: http://plrg.eecs.uci.edu/git/?p=c11tester.git;a=blobdiff_plain;f=funcnode.cc;h=8cb39da9697efbbe0f7a8da397c2988f314f2c57;hp=d60fbe1c9a65b5762cf25b4507ef25f6f80fe3e0;hb=cbcd5a166532cd048a90f1ed3eb70adab4a1cfdc;hpb=c22006fbddb0f954f658252f1c6dd336d069c77d diff --git a/funcnode.cc b/funcnode.cc index d60fbe1c..8cb39da9 100644 --- a/funcnode.cc +++ b/funcnode.cc @@ -1,15 +1,48 @@ +#include "action.h" +#include "history.h" #include "funcnode.h" -#include +#include "funcinst.h" +#include "predicate.h" +#include "concretepredicate.h" -FuncNode::FuncNode() : - predicate_tree_initialized(false), - predicate_tree_entry(new Predicate(NULL, true)), +#include "model.h" + +FuncNode::FuncNode(ModelHistory * history) : + history(history), + exit_count(0), + marker(1), func_inst_map(), inst_list(), entry_insts(), - thrd_read_map(), - predicate_tree_backedges() -{} + predicate_tree_position(), + edge_table(32), + out_edges() +{ + predicate_tree_entry = new Predicate(NULL, true); + predicate_tree_entry->add_predicate_expr(NOPREDICATE, NULL, true); + predicate_tree_exit = new Predicate(NULL, false, true); + + // Memories that are reclaimed after each execution + action_list_buffer = new SnapList(); + read_locations = new loc_set_t(); + write_locations = new loc_set_t(); + val_loc_map = new HashTable(); + loc_may_equal_map = new HashTable(); + + //values_may_read_from = new value_set_t(); +} + +/* Reallocate snapshotted memories when new executions start */ +void FuncNode::set_new_exec_flag() +{ + action_list_buffer = new SnapList(); + read_locations = new loc_set_t(); + write_locations = new loc_set_t(); + val_loc_map = new HashTable(); + loc_may_equal_map = new HashTable(); + + //values_may_read_from = new value_set_t(); +} /* Check whether FuncInst with the same type, position, and location * as act has been added to func_inst_map or not. If not, add it. @@ -31,18 +64,18 @@ void FuncNode::add_inst(ModelAction *act) if ( func_inst_map.contains(position) ) { FuncInst * inst = func_inst_map.get(position); - if (inst->get_type() != act->get_type() ) { - // model_print("action with a different type occurs at line number %s\n", position); - FuncInst * func_inst = inst->search_in_collision(act); - - if (func_inst != NULL) - return; + ASSERT(inst->get_type() == act->get_type()); + int curr_execution_number = model->get_execution_number(); - func_inst = new FuncInst(act, this); - inst->get_collisions()->push_back(func_inst); - inst_list.push_back(func_inst); // delete? + /* Reset locations when new executions start */ + if (inst->get_execution_number() != curr_execution_number) { + inst->set_location(act->get_location()); + inst->set_execution_number(curr_execution_number); } + if (inst->get_location() != act->get_location()) + inst->not_single_location(); + return; } @@ -105,36 +138,62 @@ void FuncNode::add_entry_inst(FuncInst * inst) */ void FuncNode::update_tree(action_list_t * act_list) { - if (act_list == NULL) - return; - else if (act_list->size() == 0) + if (act_list == NULL || act_list->size() == 0) return; + HashTable * write_history = history->getWriteHistory(); + /* build inst_list from act_list for later processing */ func_inst_list_t inst_list; - action_list_t read_act_list; - HashTable act_inst_map(128); + action_list_t rw_act_list; for (sllnode * it = act_list->begin(); it != NULL; it = it->getNext()) { ModelAction * act = it->getVal(); FuncInst * func_inst = get_inst(act); + void * loc = act->get_location(); if (func_inst == NULL) continue; inst_list.push_back(func_inst); + bool act_added = false; + + if (act->is_write()) { + rw_act_list.push_back(act); + act_added = true; + if (!write_locations->contains(loc)) { + write_locations->add(loc); + history->update_loc_wr_func_nodes_map(loc, this); + } + } -// model_print("position: %s ", act->get_position()); -// act->print(); - - if (func_inst->is_read()) { - read_act_list.push_back(act); - act_inst_map.put(act, func_inst); + if (act->is_read()) { + if (!act_added) + rw_act_list.push_back(act); + + /* If func_inst may only read_from a single location, then: + * + * The first time an action reads from some location, + * import all the values that have been written to this + * location from ModelHistory and notify ModelHistory + * that this FuncNode may read from this location. + */ + if (!read_locations->contains(loc) && func_inst->is_single_location()) { + read_locations->add(loc); + value_set_t * write_values = write_history->get(loc); + add_to_val_loc_map(write_values, loc); + history->update_loc_rd_func_nodes_map(loc, this); + } } } +// model_print("function %s\n", func_name); +// print_val_loc_map(); + update_inst_tree(&inst_list); - update_predicate_tree(&read_act_list, &act_inst_map); + update_predicate_tree(&rw_act_list); + +// print_predicate_tree(); } /** @@ -170,146 +229,97 @@ void FuncNode::update_inst_tree(func_inst_list_t * inst_list) } } -/* @param tid thread id - * Store the values read by atomic read actions into thrd_read_map */ -void FuncNode::store_read(ModelAction * act, uint32_t tid) -{ - ASSERT(act); - - void * location = act->get_location(); - uint64_t read_from_val = act->get_reads_from_value(); - - /* resize and initialize */ - uint32_t old_size = thrd_read_map.size(); - if (old_size <= tid) { - thrd_read_map.resize(tid + 1); - for (uint32_t i = old_size; i < tid + 1;i++) - thrd_read_map[i] = new read_map_t(); - } - - read_map_t * read_map = thrd_read_map[tid]; - read_map->put(location, read_from_val); - - /* Store the memory locations where atomic reads happen */ - // read_locations.add(location); -} - -uint64_t FuncNode::query_last_read(void * location, uint32_t tid) -{ - if (thrd_read_map.size() <= tid) - return 0xdeadbeef; - - read_map_t * read_map = thrd_read_map[tid]; - - /* last read value not found */ - if ( !read_map->contains(location) ) - return 0xdeadbeef; - - uint64_t read_val = read_map->get(location); - return read_val; -} - -/* @param tid thread id - * Reset read map for a thread. This function shall only be called - * when a thread exits a function - */ -void FuncNode::clear_read_map(uint32_t tid) -{ - if (thrd_read_map.size() <= tid) - return; - - thrd_read_map[tid]->reset(); -} - -void FuncNode::update_predicate_tree(action_list_t * act_list, HashTable * act_inst_map) +void FuncNode::update_predicate_tree(action_list_t * act_list) { if (act_list == NULL || act_list->size() == 0) return; -/* - if (predicate_tree_initialized) { - return; - } - predicate_tree_initialized = true; -*/ - /* map a FuncInst to the parent of its predicate */ + incr_marker(); + + /* Map a FuncInst to the its predicate */ HashTable inst_pred_map(128); - HashTable read_val_map(128); - HashTable loc_inst_map(128); + + // Number FuncInsts to detect loops + HashTable inst_id_map(128); + uint32_t inst_counter = 0; + + /* Only need to store the locations of read actions */ + HashTable loc_act_map(128); sllnode *it = act_list->begin(); Predicate * curr_pred = predicate_tree_entry; - while (it != NULL) { - ModelAction * curr_act = it->getVal(); - FuncInst * curr_inst = act_inst_map->get(curr_act); - Predicate * old_pred = curr_pred; - read_val_map.put(curr_inst, curr_act->get_reads_from_value()); + ModelAction * next_act = it->getVal(); + FuncInst * next_inst = get_inst(next_act); + next_inst->set_associated_act(next_act, marker); - bool branch_found = follow_branch(&curr_pred, curr_inst, &read_val_map, &loc_inst_map); + SnapVector unset_predicates = SnapVector(); + bool branch_found = follow_branch(&curr_pred, next_inst, next_act, &unset_predicates); - // check back edges - if (!branch_found) { - Predicate * back_pred = curr_pred->get_backedge(); - if (back_pred != NULL) { - curr_pred = back_pred; + // A branch with unset predicate expression is detected + if (!branch_found && unset_predicates.size() != 0) { + ASSERT(unset_predicates.size() == 1); + Predicate * one_branch = unset_predicates[0]; + + bool amended = amend_predicate_expr(&curr_pred, next_inst, next_act); + if (amended) continue; + else { + curr_pred = one_branch; + branch_found = true; } + } - if (inst_pred_map.contains(curr_inst)) { - back_pred = inst_pred_map.get(curr_inst); - curr_pred->set_backedge(back_pred); + // Detect loops + if (!branch_found && inst_id_map.contains(next_inst)) { + FuncInst * curr_inst = curr_pred->get_func_inst(); + uint32_t curr_id = inst_id_map.get(curr_inst); + uint32_t next_id = inst_id_map.get(next_inst); + + if (curr_id >= next_id) { + Predicate * old_pred = inst_pred_map.get(next_inst); + Predicate * back_pred = old_pred->get_parent(); + + curr_pred->add_backedge(back_pred); curr_pred = back_pred; continue; } } - if (!inst_pred_map.contains(curr_inst)) - inst_pred_map.put(curr_inst, old_pred); - + // Generate new branches if (!branch_found) { - if ( loc_inst_map.contains(curr_inst->get_location()) ) { - Predicate * new_pred1 = new Predicate(curr_inst); - new_pred1->add_predicate(EQUALITY, curr_inst->get_location(), true); - - Predicate * new_pred2 = new Predicate(curr_inst); - new_pred2->add_predicate(EQUALITY, curr_inst->get_location(), false); - - curr_pred->add_child(new_pred1); - curr_pred->add_child(new_pred2); - //new_pred1->add_parent(curr_pred); - //new_pred2->add_parent(curr_pred); - - FuncInst * last_inst = loc_inst_map.get(curr_inst->get_location()); - uint64_t last_read = read_val_map.get(last_inst); - if ( last_read == read_val_map.get(curr_inst) ) - curr_pred = new_pred1; - else - curr_pred = new_pred2; - } else { - Predicate * new_pred = new Predicate(curr_inst); - curr_pred->add_child(new_pred); - //new_pred->add_parent(curr_pred); - - curr_pred = new_pred; - } + SnapVector half_pred_expressions; + infer_predicates(next_inst, next_act, &loc_act_map, &half_pred_expressions); + generate_predicates(&curr_pred, next_inst, &half_pred_expressions); + continue; + } + + if (next_act->is_write()) + curr_pred->set_write(true); + + if (next_act->is_read()) { + loc_act_map.put(next_act->get_location(), next_act); } - loc_inst_map.put(curr_inst->get_location(), curr_inst); + inst_pred_map.put(next_inst, curr_pred); + if (!inst_id_map.contains(next_inst)) + inst_id_map.put(next_inst, inst_counter++); + it = it->getNext(); + curr_pred->incr_expl_count(); } - model_print("function %s\n", func_name); - print_predicate_tree(); + curr_pred->set_exit(predicate_tree_exit); } -/* Given curr_pred and next_inst, find the branch following curr_pred that contains next_inst and the correct predicate +/* Given curr_pred and next_inst, find the branch following curr_pred that + * contains next_inst and the correct predicate. * @return true if branch found, false otherwise. */ bool FuncNode::follow_branch(Predicate ** curr_pred, FuncInst * next_inst, - HashTable * read_val_map, HashTable * loc_inst_map) + ModelAction * next_act, SnapVector * unset_predicates) { - /* check if a branch with func_inst and corresponding predicate exists */ + /* Check if a branch with func_inst and corresponding predicate exists */ bool branch_found = false; ModelVector * branches = (*curr_pred)->get_children(); for (uint i = 0; i < branches->size(); i++) { @@ -317,72 +327,396 @@ bool FuncNode::follow_branch(Predicate ** curr_pred, FuncInst * next_inst, if (branch->get_func_inst() != next_inst) continue; + /* Check against predicate expressions */ + bool predicate_correct = true; PredExprSet * pred_expressions = branch->get_pred_expressions(); + PredExprSetIter * pred_expr_it = pred_expressions->iterator(); - /* no predicate, follow the only branch */ + /* Only read and rmw actions my have unset predicate expressions */ if (pred_expressions->getSize() == 0) { -// model_print("no predicate exists: "); next_inst->print(); - *curr_pred = branch; - branch_found = true; - break; + predicate_correct = false; + unset_predicates->push_back(branch); } - PredExprSetIter * pred_expr_it = pred_expressions->iterator(); while (pred_expr_it->hasNext()) { pred_expr * pred_expression = pred_expr_it->next(); uint64_t last_read, next_read; - FuncInst * last_inst; bool equality; switch(pred_expression->token) { + case NOPREDICATE: + predicate_correct = true; + break; case EQUALITY: - last_inst = loc_inst_map->get(next_inst->get_location()); - last_read = read_val_map->get(last_inst); - next_read = read_val_map->get(next_inst); + FuncInst * to_be_compared; + ModelAction * last_act; + + to_be_compared = pred_expression->func_inst; + last_act = to_be_compared->get_associated_act(marker); + + last_read = last_act->get_reads_from_value(); + next_read = next_act->get_reads_from_value(); equality = (last_read == next_read); + if (equality != pred_expression->value) + predicate_correct = false; - if (equality == pred_expression->value) { - *curr_pred = branch; -// model_print("predicate: token: %d, location: %p, value: %d - ", pred_expression->token, pred_expression->location, pred_expression->value); next_inst->print(); - branch_found = true; - } break; case NULLITY: + next_read = next_act->get_reads_from_value(); + equality = ((void*)next_read == NULL); + if (equality != pred_expression->value) + predicate_correct = false; break; default: + predicate_correct = false; model_print("unkown predicate token\n"); break; } } + if (predicate_correct) { + *curr_pred = branch; + branch_found = true; + break; + } } return branch_found; } -void FuncNode::print_predicate_tree() +/* Infer predicate expressions, which are generated in FuncNode::generate_predicates */ +void FuncNode::infer_predicates(FuncInst * next_inst, ModelAction * next_act, + HashTable * loc_act_map, + SnapVector * half_pred_expressions) { - model_print("digraph function_%s {\n", func_name); - predicate_tree_entry->print_pred_subtree(); - model_print("}\n"); // end of graph + void * loc = next_act->get_location(); + + if (next_inst->is_read()) { + /* read + rmw */ + if ( loc_act_map->contains(loc) ) { + ModelAction * last_act = loc_act_map->get(loc); + FuncInst * last_inst = get_inst(last_act); + struct half_pred_expr * expression = new half_pred_expr(EQUALITY, last_inst); + half_pred_expressions->push_back(expression); + } else if ( next_inst->is_single_location() ){ + loc_set_t * loc_may_equal = loc_may_equal_map->get(loc); + + if (loc_may_equal != NULL) { + loc_set_iter * loc_it = loc_may_equal->iterator(); + while (loc_it->hasNext()) { + void * neighbor = loc_it->next(); + if (loc_act_map->contains(neighbor)) { + ModelAction * last_act = loc_act_map->get(neighbor); + FuncInst * last_inst = get_inst(last_act); + + struct half_pred_expr * expression = new half_pred_expr(EQUALITY, last_inst); + half_pred_expressions->push_back(expression); + } + } + } + } else { + // next_inst is not single location + uint64_t read_val = next_act->get_reads_from_value(); + + // only infer NULLITY predicate when it is actually NULL. + if ( (void*)read_val == NULL) { + struct half_pred_expr * expression = new half_pred_expr(NULLITY, NULL); + half_pred_expressions->push_back(expression); + } + } + } else { + /* Pure writes */ + // TODO: do anything here? + } } -/* @param tid thread id - * Print the values read by the last read actions for each memory location +/* Able to generate complex predicates when there are multiple predciate expressions */ +void FuncNode::generate_predicates(Predicate ** curr_pred, FuncInst * next_inst, + SnapVector * half_pred_expressions) +{ + if (half_pred_expressions->size() == 0) { + Predicate * new_pred = new Predicate(next_inst); + (*curr_pred)->add_child(new_pred); + new_pred->set_parent(*curr_pred); + + /* entry predicates and predicates containing pure write actions + * have no predicate expressions */ + if ( (*curr_pred)->is_entry_predicate() ) + new_pred->add_predicate_expr(NOPREDICATE, NULL, true); + else if (next_inst->is_write()) { + /* next_inst->is_write() <==> pure writes */ + new_pred->add_predicate_expr(NOPREDICATE, NULL, true); + } + + return; + } + + SnapVector predicates; + + struct half_pred_expr * half_expr = (*half_pred_expressions)[0]; + predicates.push_back(new Predicate(next_inst)); + predicates.push_back(new Predicate(next_inst)); + + predicates[0]->add_predicate_expr(half_expr->token, half_expr->func_inst, true); + predicates[1]->add_predicate_expr(half_expr->token, half_expr->func_inst, false); + + for (uint i = 1; i < half_pred_expressions->size(); i++) { + half_expr = (*half_pred_expressions)[i]; + + uint old_size = predicates.size(); + for (uint j = 0; j < old_size; j++) { + Predicate * pred = predicates[j]; + Predicate * new_pred = new Predicate(next_inst); + new_pred->copy_predicate_expr(pred); + + pred->add_predicate_expr(half_expr->token, half_expr->func_inst, true); + new_pred->add_predicate_expr(half_expr->token, half_expr->func_inst, false); + + predicates.push_back(new_pred); + } + } + + for (uint i = 0; i < predicates.size(); i++) { + Predicate * pred= predicates[i]; + (*curr_pred)->add_child(pred); + pred->set_parent(*curr_pred); + } + + /* Free memories allocated by infer_predicate */ + for (uint i = 0; i < half_pred_expressions->size(); i++) { + struct half_pred_expr * tmp = (*half_pred_expressions)[i]; + snapshot_free(tmp); + } +} + +/* Amend predicates that contain no predicate expressions. Currenlty only amend with NULLITY predicates */ +bool FuncNode::amend_predicate_expr(Predicate ** curr_pred, FuncInst * next_inst, ModelAction * next_act) +{ + // there should only be only child + Predicate * unset_pred = (*curr_pred)->get_children()->back(); + uint64_t read_val = next_act->get_reads_from_value(); + + // only generate NULLITY predicate when it is actually NULL. + if ( !next_inst->is_single_location() && (void*)read_val == NULL ) { + Predicate * new_pred = new Predicate(next_inst); + + (*curr_pred)->add_child(new_pred); + new_pred->set_parent(*curr_pred); + + unset_pred->add_predicate_expr(NULLITY, NULL, false); + new_pred->add_predicate_expr(NULLITY, NULL, true); + + return true; + } + + return false; +} + +void FuncNode::add_to_val_loc_map(uint64_t val, void * loc) +{ + loc_set_t * locations = val_loc_map->get(val); + + if (locations == NULL) { + locations = new loc_set_t(); + val_loc_map->put(val, locations); + } + + update_loc_may_equal_map(loc, locations); + locations->add(loc); + // values_may_read_from->add(val); +} + +void FuncNode::add_to_val_loc_map(value_set_t * values, void * loc) +{ + if (values == NULL) + return; + + value_set_iter * it = values->iterator(); + while (it->hasNext()) { + uint64_t val = it->next(); + add_to_val_loc_map(val, loc); + } +} + +void FuncNode::update_loc_may_equal_map(void * new_loc, loc_set_t * old_locations) +{ + if ( old_locations->contains(new_loc) ) + return; + + loc_set_t * neighbors = loc_may_equal_map->get(new_loc); + + if (neighbors == NULL) { + neighbors = new loc_set_t(); + loc_may_equal_map->put(new_loc, neighbors); + } + + loc_set_iter * loc_it = old_locations->iterator(); + while (loc_it->hasNext()) { + // new_loc: { old_locations, ... } + void * member = loc_it->next(); + neighbors->add(member); + + // for each i in old_locations, i : { new_loc, ... } + loc_set_t * _neighbors = loc_may_equal_map->get(member); + if (_neighbors == NULL) { + _neighbors = new loc_set_t(); + loc_may_equal_map->put(member, _neighbors); + } + _neighbors->add(new_loc); + } +} + +/* Every time a thread enters a function, set its position to the predicate tree entry */ +void FuncNode::init_predicate_tree_position(thread_id_t tid) +{ + int thread_id = id_to_int(tid); + if (predicate_tree_position.size() <= (uint) thread_id) + predicate_tree_position.resize(thread_id + 1); + + predicate_tree_position[thread_id] = predicate_tree_entry; +} + +void FuncNode::set_predicate_tree_position(thread_id_t tid, Predicate * pred) +{ + int thread_id = id_to_int(tid); + predicate_tree_position[thread_id] = pred; +} + +/* @return The position of a thread in a predicate tree */ +Predicate * FuncNode::get_predicate_tree_position(thread_id_t tid) +{ + int thread_id = id_to_int(tid); + return predicate_tree_position[thread_id]; +} + +/* Make sure elements of thrd_inst_act_map are initialized properly when threads enter functions */ +void FuncNode::init_inst_act_map(thread_id_t tid) +{ + int thread_id = id_to_int(tid); + SnapVector * thrd_inst_act_map = history->getThrdInstActMap(func_id); + uint old_size = thrd_inst_act_map->size(); + + if (thrd_inst_act_map->size() <= (uint) thread_id) { + uint new_size = thread_id + 1; + thrd_inst_act_map->resize(new_size); + + for (uint i = old_size; i < new_size; i++) + (*thrd_inst_act_map)[i] = new inst_act_map_t(128); + } +} + +/* Reset elements of thrd_inst_act_map when threads exit functions */ +void FuncNode::reset_inst_act_map(thread_id_t tid) +{ + int thread_id = id_to_int(tid); + SnapVector * thrd_inst_act_map = history->getThrdInstActMap(func_id); + + inst_act_map_t * map = (*thrd_inst_act_map)[thread_id]; + map->reset(); +} + +void FuncNode::update_inst_act_map(thread_id_t tid, ModelAction * read_act) +{ + int thread_id = id_to_int(tid); + SnapVector * thrd_inst_act_map = history->getThrdInstActMap(func_id); + + inst_act_map_t * map = (*thrd_inst_act_map)[thread_id]; + FuncInst * read_inst = get_inst(read_act); + map->put(read_inst, read_act); +} + +inst_act_map_t * FuncNode::get_inst_act_map(thread_id_t tid) +{ + int thread_id = id_to_int(tid); + SnapVector * thrd_inst_act_map = history->getThrdInstActMap(func_id); + + return (*thrd_inst_act_map)[thread_id]; +} + +/* Add FuncNodes that this node may follow */ +void FuncNode::add_out_edge(FuncNode * other) +{ + if ( !edge_table.contains(other) ) { + edge_table.put(other, OUT_EDGE); + out_edges.push_back(other); + return; + } + + edge_type_t edge = edge_table.get(other); + if (edge == IN_EDGE) { + edge_table.put(other, BI_EDGE); + out_edges.push_back(other); + } +} + +/* Compute the distance between this FuncNode and the target node. + * Return -1 if the target node is unreachable or the actual distance + * is greater than max_step. */ -/* -void FuncNode::print_last_read(uint32_t tid) +int FuncNode::compute_distance(FuncNode * target, int max_step) { - ASSERT(thrd_read_map.size() > tid); - read_map_t * read_map = thrd_read_map[tid]; + if (target == NULL) + return -1; + else if (target == this) + return 0; - mllnode * it; - for (it = read_locations.begin();it != NULL;it=it->getNext()) { - if ( !read_map->contains(it->getVal()) ) - break; + SnapList queue; + HashTable distances(128); + + queue.push_back(this); + distances.put(this, 0); + + while (!queue.empty()) { + FuncNode * curr = queue.front(); + queue.pop_front(); + int dist = distances.get(curr); + + if (max_step <= dist) + return -1; + + ModelList * outEdges = curr->get_out_edges(); + mllnode * it; + for (it = outEdges->begin(); it != NULL; it = it->getNext()) { + FuncNode * out_node = it->getVal(); - uint64_t read_val = read_map->get(it->getVal()); - model_print("last read of thread %d at %p: 0x%x\n", tid, it->getVal(), read_val); + /* This node has not been visited before */ + if ( !distances.contains(out_node) ) { + if (out_node == target) + return dist + 1; + + queue.push_back(out_node); + distances.put(out_node, dist + 1); + } + } } + + /* Target node is unreachable */ + return -1; } + +void FuncNode::print_predicate_tree() +{ + model_print("digraph function_%s {\n", func_name); + predicate_tree_entry->print_pred_subtree(); + predicate_tree_exit->print_predicate(); + model_print("}\n"); // end of graph +} + +void FuncNode::print_val_loc_map() +{ +/* + value_set_iter * val_it = values_may_read_from->iterator(); + while (val_it->hasNext()) { + uint64_t value = val_it->next(); + model_print("val %llx: ", value); + + loc_set_t * locations = val_loc_map->get(value); + loc_set_iter * loc_it = locations->iterator(); + while (loc_it->hasNext()) { + void * location = loc_it->next(); + model_print("%p ", location); + } + model_print("\n"); + } */ +}