+#include "action.h"
+#include "history.h"
#include "funcnode.h"
+#include "funcinst.h"
+#include "predicate.h"
+#include "concretepredicate.h"
+
+#include "model.h"
+#include <cmath>
FuncNode::FuncNode(ModelHistory * history) :
history(history),
- predicate_tree_initialized(false),
exit_count(0),
+ marker(1),
func_inst_map(),
inst_list(),
entry_insts(),
- action_list_buffer(),
- predicate_tree_position()
+ predicate_tree_position(),
+ edge_table(32),
+ out_edges()
{
predicate_tree_entry = new Predicate(NULL, true);
predicate_tree_entry->add_predicate_expr(NOPREDICATE, NULL, true);
- // memories that are reclaimed after each execution
+ predicate_tree_exit = new Predicate(NULL, false, true);
+ predicate_tree_exit->alloc_pre_exit_predicates();
+ predicate_tree_exit->set_depth(MAX_DEPTH);
+
+ /* Snapshot data structures below */
+ action_list_buffer = new SnapList<action_list_t *>();
read_locations = new loc_set_t();
- val_loc_map = new HashTable<uint64_t, loc_set_t *, uint64_t, 0>();
+ write_locations = new loc_set_t();
+ val_loc_map = new HashTable<uint64_t, loc_set_t *, uint64_t, 0, snapshot_malloc, snapshot_calloc, snapshot_free, int64_hash>();
loc_may_equal_map = new HashTable<void *, loc_set_t *, uintptr_t, 0>();
- thrd_inst_act_map = new SnapVector<inst_act_map_t *>();
//values_may_read_from = new value_set_t();
}
/* Reallocate snapshotted memories when new executions start */
void FuncNode::set_new_exec_flag()
{
- for (mllnode<FuncInst *> * it = inst_list.begin(); it != NULL; it = it->getNext()) {
- FuncInst * inst = it->getVal();
- inst->unset_location();
- }
-
+ action_list_buffer = new SnapList<action_list_t *>();
read_locations = new loc_set_t();
- val_loc_map = new HashTable<uint64_t, loc_set_t *, uint64_t, 0>();
+ write_locations = new loc_set_t();
+ val_loc_map = new HashTable<uint64_t, loc_set_t *, uint64_t, 0, snapshot_malloc, snapshot_calloc, snapshot_free, int64_hash>();
loc_may_equal_map = new HashTable<void *, loc_set_t *, uintptr_t, 0>();
- thrd_inst_act_map = new SnapVector<inst_act_map_t *>();
//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.
- *
- * Note: currently, actions with the same position are filtered out by process_action,
- * so the collision list of FuncInst is not used. May remove it later.
*/
void FuncNode::add_inst(ModelAction *act)
{
if (position == NULL)
return;
- if ( func_inst_map.contains(position) ) {
- FuncInst * inst = func_inst_map.get(position);
+ FuncInst * func_inst = func_inst_map.get(position);
- ASSERT(inst->get_type() == act->get_type());
+ /* This position has not been inserted into hashtable before */
+ if (func_inst == NULL) {
+ func_inst = create_new_inst(act);
+ func_inst_map.put(position, func_inst);
+ return;
+ }
- // locations are set to NULL when new executions start
- if (inst->get_location() == NULL)
- inst->set_location(act->get_location());
+ /* Volatile variables that use ++ or -- syntax may result in read and write actions with the same position */
+ if (func_inst->get_type() != act->get_type()) {
+ FuncInst * collision_inst = func_inst->search_in_collision(act);
- if (inst->get_location() != act->get_location())
- inst->not_single_location();
+ if (collision_inst == NULL) {
+ collision_inst = create_new_inst(act);
+ func_inst->add_to_collision(collision_inst);
+ return;
+ } else {
+ func_inst = collision_inst;
+ }
+ }
- return;
+ ASSERT(func_inst->get_type() == act->get_type());
+ int curr_execution_number = model->get_execution_number();
+
+ /* Reset locations when new executions start */
+ if (func_inst->get_execution_number() != curr_execution_number) {
+ func_inst->set_location(act->get_location());
+ func_inst->set_execution_number(curr_execution_number);
}
+ /* Mark the memory location of such inst as not unique */
+ if (func_inst->get_location() != act->get_location())
+ func_inst->not_single_location();
+}
+
+FuncInst * FuncNode::create_new_inst(ModelAction * act)
+{
FuncInst * func_inst = new FuncInst(act, this);
+ int exec_num = model->get_execution_number();
+ func_inst->set_execution_number(exec_num);
- func_inst_map.put(position, func_inst);
inst_list.push_back(func_inst);
+
+ return func_inst;
}
+
/* Get the FuncInst with the same type, position, and location
* as act
*
action_type inst_type = inst->get_type();
action_type act_type = act->get_type();
- // else if branch: an RMWRCAS action is converted to a RMW or READ action
- if (inst_type == act_type)
+ if (inst_type == act_type) {
return inst;
+ }
+ /* RMWRCAS actions are converted to RMW or READ actions */
else if (inst_type == ATOMIC_RMWRCAS &&
- (act_type == ATOMIC_RMW || act_type == ATOMIC_READ))
+ (act_type == ATOMIC_RMW || act_type == ATOMIC_READ)) {
return inst;
-
- return NULL;
+ }
+ /* Return the FuncInst in the collision list */
+ else {
+ return inst->search_in_collision(act);
+ }
}
return;
mllnode<FuncInst *> * it;
- for (it = entry_insts.begin(); it != NULL; it = it->getNext()) {
+ for (it = entry_insts.begin();it != NULL;it = it->getNext()) {
if (inst == it->getVal())
return;
}
}
/**
- * @brief Convert ModelAdtion list to FuncInst list
+ * @brief Convert ModelAdtion list to FuncInst list
* @param act_list A list of ModelActions
*/
void FuncNode::update_tree(action_list_t * act_list)
if (act_list == NULL || act_list->size() == 0)
return;
- HashTable<void *, value_set_t *, uintptr_t, 4> * write_history = history->getWriteHistory();
+ HashTable<void *, value_set_t *, uintptr_t, 0> * 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;
+ action_list_t rw_act_list;
- for (sllnode<ModelAction *> * it = act_list->begin(); it != NULL; it = it->getNext()) {
+ for (sllnode<ModelAction *> * 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);
+ }
+ }
- if (func_inst->is_read()) {
- read_act_list.push_back(act);
+ 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.
+ * 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.
*/
- void * loc = act->get_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->add_to_loc_func_nodes_map(loc, this);
+ history->update_loc_rd_func_nodes_map(loc, this);
}
}
}
// print_val_loc_map();
update_inst_tree(&inst_list);
- update_predicate_tree(&read_act_list);
+ update_predicate_tree(&rw_act_list);
// print_predicate_tree();
}
-/**
+/**
* @brief Link FuncInsts in inst_list - add one FuncInst to another's predecessors and successors
* @param inst_list A list of FuncInsts
*/
if (act_list == NULL || act_list->size() == 0)
return;
- /* map a FuncInst to the its predicate */
+ incr_marker();
+
+ /* Map a FuncInst to the its predicate */
HashTable<FuncInst *, Predicate *, uintptr_t, 0> inst_pred_map(128);
- // number FuncInsts to detect loops
+ // Number FuncInsts to detect loops
HashTable<FuncInst *, uint32_t, uintptr_t, 0> inst_id_map(128);
uint32_t inst_counter = 0;
+ /* Only need to store the locations of read actions */
HashTable<void *, ModelAction *, uintptr_t, 0> loc_act_map(128);
- HashTable<FuncInst *, ModelAction *, uintptr_t, 0> inst_act_map(128);
sllnode<ModelAction *> *it = act_list->begin();
Predicate * curr_pred = predicate_tree_entry;
while (it != NULL) {
ModelAction * next_act = it->getVal();
FuncInst * next_inst = get_inst(next_act);
+ next_inst->set_associated_act(next_act, marker);
SnapVector<Predicate *> unset_predicates = SnapVector<Predicate *>();
- bool branch_found = follow_branch(&curr_pred, next_inst, next_act, &inst_act_map, &unset_predicates);
+ bool branch_found = follow_branch(&curr_pred, next_inst, next_act, &unset_predicates);
- // no predicate expressions
+ // 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];
}
}
- // detect loops
+ // 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);
curr_pred->add_backedge(back_pred);
curr_pred = back_pred;
-
continue;
}
}
- // generate new branches
+ // Generate new branches
if (!branch_found) {
SnapVector<struct half_pred_expr *> half_pred_expressions;
- void * loc = next_act->get_location();
-
- 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 generate 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);
- }
- }
-
- if (half_pred_expressions.size() == 0) {
- // no predicate needs to be generated
- Predicate * new_pred = new Predicate(next_inst);
- curr_pred->add_child(new_pred);
- new_pred->set_parent(curr_pred);
+ infer_predicates(next_inst, next_act, &loc_act_map, &half_pred_expressions);
+ generate_predicates(&curr_pred, next_inst, &half_pred_expressions);
+ continue;
+ }
- if (curr_pred->is_entry_predicate())
- new_pred->add_predicate_expr(NOPREDICATE, NULL, true);
+ if (next_act->is_write())
+ curr_pred->set_write(true);
- curr_pred = new_pred;
- } else {
- generate_predicate(&curr_pred, next_inst, &half_pred_expressions);
- bool branch_found = follow_branch(&curr_pred, next_inst, next_act, &inst_act_map, NULL);
- ASSERT(branch_found);
- }
+ if (next_act->is_read()) {
+ loc_act_map.put(next_act->get_location(), next_act);
}
inst_pred_map.put(next_inst, curr_pred);
if (!inst_id_map.contains(next_inst))
inst_id_map.put(next_inst, inst_counter++);
- loc_act_map.put(next_act->get_location(), next_act);
- inst_act_map.put(next_inst, next_act);
it = it->getNext();
+ curr_pred->incr_expl_count();
+ }
+
+ if (curr_pred->get_exit() == NULL) {
+ // Exit predicate is unset yet
+ 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.
+ * contains next_inst and the correct predicate.
* @return true if branch found, false otherwise.
*/
-bool FuncNode::follow_branch(Predicate ** curr_pred, FuncInst * next_inst, ModelAction * next_act,
- HashTable<FuncInst *, ModelAction *, uintptr_t, 0> * inst_act_map,
- SnapVector<Predicate *> * unset_predicates)
+bool FuncNode::follow_branch(Predicate ** curr_pred, FuncInst * next_inst,
+ModelAction * next_act, SnapVector<Predicate *> * 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<Predicate *> * branches = (*curr_pred)->get_children();
- for (uint i = 0; i < branches->size(); i++) {
+ for (uint i = 0;i < branches->size();i++) {
Predicate * branch = (*branches)[i];
if (branch->get_func_inst() != next_inst)
continue;
- /* check against predicate expressions */
+ /* Check against predicate expressions */
bool predicate_correct = true;
PredExprSet * pred_expressions = branch->get_pred_expressions();
PredExprSetIter * pred_expr_it = pred_expressions->iterator();
+ /* Only read and rmw actions my have unset predicate expressions */
if (pred_expressions->getSize() == 0) {
predicate_correct = false;
unset_predicates->push_back(branch);
ModelAction * last_act;
to_be_compared = pred_expression->func_inst;
- last_act = inst_act_map->get(to_be_compared);
+ 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();
break;
case NULLITY:
next_read = next_act->get_reads_from_value();
- equality = ((void*)next_read == NULL);
+ // TODO: implement likely to be null
+ equality = ( (void*) (next_read & 0xffffffff) == NULL);
if (equality != pred_expression->value)
predicate_correct = false;
break;
return branch_found;
}
+/* Infer predicate expressions, which are generated in FuncNode::generate_predicates */
+void FuncNode::infer_predicates(FuncInst * next_inst, ModelAction * next_act,
+HashTable<void *, ModelAction *, uintptr_t, 0> * loc_act_map,
+SnapVector<struct half_pred_expr *> * half_pred_expressions)
+{
+ 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?
+ }
+}
+
/* Able to generate complex predicates when there are multiple predciate expressions */
-void FuncNode::generate_predicate(Predicate ** curr_pred, FuncInst * next_inst,
- SnapVector<struct half_pred_expr *> * half_pred_expressions)
+void FuncNode::generate_predicates(Predicate ** curr_pred, FuncInst * next_inst,
+SnapVector<struct half_pred_expr *> * half_pred_expressions)
{
- ASSERT(half_pred_expressions->size() != 0);
+ 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<Predicate *> predicates;
struct half_pred_expr * half_expr = (*half_pred_expressions)[0];
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++) {
+ 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++) {
+ 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);
}
}
- for (uint i = 0; i < predicates.size(); i++) {
+ 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 */
}
}
+/* 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);
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<inst_act_map_t *> * 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++)
+ 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<inst_act_map_t *> * 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<inst_act_map_t *> * 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<inst_act_map_t *> * thrd_inst_act_map = history->getThrdInstActMap(func_id);
+
return (*thrd_inst_act_map)[thread_id];
}
-void FuncNode::print_predicate_tree()
+/* Add FuncNodes that this node may follow */
+void FuncNode::add_out_edge(FuncNode * other)
{
- model_print("digraph function_%s {\n", func_name);
- predicate_tree_entry->print_pred_subtree();
- model_print("}\n"); // end of graph
+ 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.
+ */
+int FuncNode::compute_distance(FuncNode * target, int max_step)
+{
+ if (target == NULL)
+ return -1;
+ else if (target == this)
+ return 0;
+
+ SnapList<FuncNode *> queue;
+ HashTable<FuncNode *, int, uintptr_t, 0> 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<FuncNode *> * outEdges = curr->get_out_edges();
+ mllnode<FuncNode *> * it;
+ for (it = outEdges->begin();it != NULL;it = it->getNext()) {
+ FuncNode * out_node = it->getVal();
+
+ /* 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_val_loc_map()
+void FuncNode::assign_base_score()
{
-/*
- 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);
+ SnapVector<Predicate *> leaves;
+ SnapList<Predicate *> queue;
+ queue.push_front(predicate_tree_entry);
+
+ // assign leaf score
+ while ( !queue.empty() ) {
+ Predicate * node = queue.back();
+ queue.pop_back();
+
+ ModelVector<Predicate *> * children = node->get_children();
+ if (children->empty()) {
+ node->set_weight(1);
+ leaves.push_back(node);
}
- model_print("\n");
+
+ for (uint i = 0; i < children->size(); i++)
+ queue.push_front( (*children)[i] );
}
-*/
+
+ // assign scores for internal nodes;
+ while ( !leaves.empty() ) {
+ Predicate * leaf = leaves.back();
+ leaves.pop_back();
+
+ Predicate * curr = leaf->get_parent();
+ while (curr != NULL) {
+ if (curr->get_weight() != 0) {
+ // Has been exlpored
+ break;
+ }
+
+ ModelVector<Predicate *> * children = curr->get_children();
+ double weight_sum = 0;
+ bool has_unassigned_node = false;
+
+ for (uint i = 0; i < children->size(); i++) {
+ Predicate * child = (*children)[i];
+
+ // If a child has unassigned weight
+ double weight = child->get_weight();
+ if (weight == 0) {
+ has_unassigned_node = true;
+ break;
+ } else
+ weight_sum += weight;
+ }
+
+ if (!has_unassigned_node) {
+ double average_weight = (double) weight_sum / (double) children->size();
+ double weight = average_weight * pow(0.9, curr->get_depth());
+ curr->set_weight(weight);
+ } else
+ break;
+
+ curr = curr->get_parent();
+ }
+ }
+}
+
+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
}