+#define __STDC_FORMAT_MACROS
+#include <inttypes.h>
+
+#include <string.h>
+
#include "nodestack.h"
#include "action.h"
#include "common.h"
#include "model.h"
+#include "threads-model.h"
+#include "modeltypes.h"
-/** @brief Node constructor */
-Node::Node(ModelAction *act, int nthreads)
- : action(act),
+/**
+ * @brief Node constructor
+ *
+ * Constructs a single Node for use in a NodeStack. Each Node is associated
+ * with exactly one ModelAction (exception: the first Node should be created
+ * as an empty stub, to represent the first thread "choice") and up to one
+ * parent.
+ *
+ * @param act The ModelAction to associate with this Node. May be NULL.
+ * @param par The parent Node in the NodeStack. May be NULL if there is no
+ * parent.
+ * @param nthreads The number of threads which exist at this point in the
+ * execution trace.
+ */
+Node::Node(ModelAction *act, Node *par, int nthreads, Node *prevfairness) :
+ read_from_status(READ_FROM_PAST),
+ action(act),
+ uninit_action(NULL),
+ parent(par),
num_threads(nthreads),
explored_children(num_threads),
backtrack(num_threads),
- numBacktracks(0)
+ fairness(num_threads),
+ numBacktracks(0),
+ enabled_array(NULL),
+ read_from_past(),
+ read_from_past_idx(0),
+ read_from_promises(),
+ read_from_promise_idx(-1),
+ future_values(),
+ future_index(-1),
+ resolve_promise(),
+ resolve_promise_idx(-1),
+ relseq_break_writes(),
+ relseq_break_index(0),
+ misc_index(0),
+ misc_max(0),
+ yield_data(NULL)
{
+ ASSERT(act);
+ act->set_node(this);
+ int currtid = id_to_int(act->get_tid());
+ int prevtid = prevfairness ? id_to_int(prevfairness->action->get_tid()) : 0;
+
+ if (model->params.fairwindow != 0) {
+ for (int i = 0; i < num_threads; i++) {
+ ASSERT(i < ((int)fairness.size()));
+ struct fairness_info *fi = &fairness[i];
+ struct fairness_info *prevfi = (parent && i < parent->get_num_threads()) ? &parent->fairness[i] : NULL;
+ if (prevfi) {
+ *fi = *prevfi;
+ }
+ if (parent && parent->is_enabled(int_to_id(i))) {
+ fi->enabled_count++;
+ }
+ if (i == currtid) {
+ fi->turns++;
+ fi->priority = false;
+ }
+ /* Do window processing */
+ if (prevfairness != NULL) {
+ if (prevfairness->parent->is_enabled(int_to_id(i)))
+ fi->enabled_count--;
+ if (i == prevtid) {
+ fi->turns--;
+ }
+ /* Need full window to start evaluating
+ * conditions
+ * If we meet the enabled count and have no
+ * turns, give us priority */
+ if ((fi->enabled_count >= model->params.enabledcount) &&
+ (fi->turns == 0))
+ fi->priority = true;
+ }
+ }
+ }
+}
+
+int Node::get_yield_data(int tid1, int tid2) const {
+ if (tid1<num_threads && tid2 < num_threads)
+ return yield_data[YIELD_INDEX(tid1,tid2,num_threads)];
+ else
+ return YIELD_S | YIELD_D;
+}
+
+void Node::update_yield(Scheduler * scheduler) {
+ if (yield_data==NULL)
+ yield_data=(int *) model_calloc(1, sizeof(int)*num_threads*num_threads);
+ //handle base case
+ if (parent == NULL) {
+ for(int i = 0; i < num_threads*num_threads; i++) {
+ yield_data[i] = YIELD_S | YIELD_D;
+ }
+ return;
+ }
+ int curr_tid=id_to_int(action->get_tid());
+
+ for(int u = 0; u < num_threads; u++) {
+ for(int v = 0; v < num_threads; v++) {
+ int yield_state=parent->get_yield_data(u, v);
+ bool next_enabled=scheduler->is_enabled(int_to_id(v));
+ bool curr_enabled=parent->is_enabled(int_to_id(v));
+ if (!next_enabled) {
+ //Compute intersection of ES and E
+ yield_state&=~YIELD_E;
+ //Check to see if we disabled the thread
+ if (u==curr_tid && curr_enabled)
+ yield_state|=YIELD_D;
+ }
+ yield_data[YIELD_INDEX(u, v, num_threads)]=yield_state;
+ }
+ yield_data[YIELD_INDEX(u, curr_tid, num_threads)]=(yield_data[YIELD_INDEX(u, curr_tid, num_threads)]&~YIELD_P)|YIELD_S;
+ }
+ //handle curr.yield(t) part of computation
+ if (action->is_yield()) {
+ for(int v = 0; v < num_threads; v++) {
+ int yield_state=yield_data[YIELD_INDEX(curr_tid, v, num_threads)];
+ if ((yield_state & (YIELD_E | YIELD_D)) && (!(yield_state & YIELD_S)))
+ yield_state |= YIELD_P;
+ yield_state &= YIELD_P;
+ if (scheduler->is_enabled(int_to_id(v))) {
+ yield_state|=YIELD_E;
+ }
+ yield_data[YIELD_INDEX(curr_tid, v, num_threads)]=yield_state;
+ }
+ }
}
/** @brief Node desctructor */
Node::~Node()
{
- if (action)
- delete action;
+ delete action;
+ if (uninit_action)
+ delete uninit_action;
+ if (enabled_array)
+ model_free(enabled_array);
+ if (yield_data)
+ model_free(yield_data);
}
/** Prints debugging info for the ModelAction associated with this Node */
-void Node::print()
+void Node::print() const
{
- if (action)
- action->print();
- else
- printf("******** empty action ********\n");
+ action->print();
+ model_print(" thread status: ");
+ if (enabled_array) {
+ for (int i = 0; i < num_threads; i++) {
+ char str[20];
+ enabled_type_to_string(enabled_array[i], str);
+ model_print("[%d: %s]", i, str);
+ }
+ model_print("\n");
+ } else
+ model_print("(info not available)\n");
+ model_print(" backtrack: %s", backtrack_empty() ? "empty" : "non-empty ");
+ for (int i = 0; i < (int)backtrack.size(); i++)
+ if (backtrack[i] == true)
+ model_print("[%d]", i);
+ model_print("\n");
+
+ model_print(" read from past: %s", read_from_past_empty() ? "empty" : "non-empty ");
+ for (int i = read_from_past_idx + 1; i < (int)read_from_past.size(); i++)
+ model_print("[%d]", read_from_past[i]->get_seq_number());
+ model_print("\n");
+
+ model_print(" read-from promises: %s", read_from_promise_empty() ? "empty" : "non-empty ");
+ for (int i = read_from_promise_idx + 1; i < (int)read_from_promises.size(); i++)
+ model_print("[%d]", read_from_promises[i]->get_seq_number());
+ model_print("\n");
+
+ model_print(" future values: %s", future_value_empty() ? "empty" : "non-empty ");
+ for (int i = future_index + 1; i < (int)future_values.size(); i++)
+ model_print("[%#" PRIx64 "]", future_values[i].value);
+ model_print("\n");
+
+ model_print(" promises: %s\n", promise_empty() ? "empty" : "non-empty");
+ model_print(" misc: %s\n", misc_empty() ? "empty" : "non-empty");
+ model_print(" rel seq break: %s\n", relseq_break_empty() ? "empty" : "non-empty");
}
+/****************************** threads backtracking **************************/
+
/**
* Checks if the Thread associated with this thread ID has been explored from
* this Node already.
* @return true if this thread choice has been explored already, false
* otherwise
*/
-bool Node::has_been_explored(thread_id_t tid)
+bool Node::has_been_explored(thread_id_t tid) const
{
int id = id_to_int(tid);
return explored_children[id];
* Checks if the backtracking set is empty.
* @return true if the backtracking set is empty
*/
-bool Node::backtrack_empty()
+bool Node::backtrack_empty() const
+{
+ return (numBacktracks == 0);
+}
+
+void Node::explore(thread_id_t tid)
{
- return numBacktracks == 0;
+ int i = id_to_int(tid);
+ ASSERT(i < ((int)backtrack.size()));
+ if (backtrack[i]) {
+ backtrack[i] = false;
+ numBacktracks--;
+ }
+ explored_children[i] = true;
}
/**
- * Explore a child Node using a given ModelAction. This updates both the
- * Node-internal and the ModelAction data to associate the ModelAction with
- * this Node.
- * @param act is the ModelAction to explore
+ * Mark the appropriate backtracking information for exploring a thread choice.
+ * @param act The ModelAction to explore
*/
-void Node::explore_child(ModelAction *act)
+void Node::explore_child(ModelAction *act, enabled_type_t *is_enabled)
{
- act->set_node(this);
+ if (!enabled_array)
+ enabled_array = (enabled_type_t *)model_malloc(sizeof(enabled_type_t) * num_threads);
+ if (is_enabled != NULL)
+ memcpy(enabled_array, is_enabled, sizeof(enabled_type_t) * num_threads);
+ else {
+ for (int i = 0; i < num_threads; i++)
+ enabled_array[i] = THREAD_DISABLED;
+ }
+
explore(act->get_tid());
}
bool Node::set_backtrack(thread_id_t id)
{
int i = id_to_int(id);
+ ASSERT(i < ((int)backtrack.size()));
if (backtrack[i])
return false;
backtrack[i] = true;
thread_id_t Node::get_next_backtrack()
{
- /* TODO: find next backtrack */
+ /** @todo Find next backtrack */
unsigned int i;
for (i = 0; i < backtrack.size(); i++)
if (backtrack[i] == true)
break;
- if (i >= backtrack.size())
- return THREAD_ID_T_NONE;
+ /* Backtrack set was empty? */
+ ASSERT(i != backtrack.size());
+
backtrack[i] = false;
numBacktracks--;
return int_to_id(i);
}
-bool Node::is_enabled(Thread *t)
+void Node::clear_backtracking()
{
- return id_to_int(t->get_id()) < num_threads;
+ for (unsigned int i = 0; i < backtrack.size(); i++)
+ backtrack[i] = false;
+ for (unsigned int i = 0; i < explored_children.size(); i++)
+ explored_children[i] = false;
+ numBacktracks = 0;
}
-void Node::explore(thread_id_t tid)
+/************************** end threads backtracking **************************/
+
+/*********************************** promise **********************************/
+
+/**
+ * Sets a promise to explore meeting with the given node.
+ * @param i is the promise index.
+ */
+void Node::set_promise(unsigned int i)
{
- int i = id_to_int(tid);
- if (backtrack[i]) {
- backtrack[i] = false;
- numBacktracks--;
+ if (i >= resolve_promise.size())
+ resolve_promise.resize(i + 1, false);
+ resolve_promise[i] = true;
+}
+
+/**
+ * Looks up whether a given promise should be satisfied by this node.
+ * @param i The promise index.
+ * @return true if the promise should be satisfied by the given ModelAction.
+ */
+bool Node::get_promise(unsigned int i) const
+{
+ return (i < resolve_promise.size()) && (int)i == resolve_promise_idx;
+}
+
+/**
+ * Increments to the next promise to resolve.
+ * @return true if we have a valid combination.
+ */
+bool Node::increment_promise()
+{
+ DBG();
+ if (resolve_promise.empty())
+ return false;
+ int prev_idx = resolve_promise_idx;
+ resolve_promise_idx++;
+ for ( ; resolve_promise_idx < (int)resolve_promise.size(); resolve_promise_idx++)
+ if (resolve_promise[resolve_promise_idx])
+ return true;
+ resolve_promise_idx = prev_idx;
+ return false;
+}
+
+/**
+ * Returns whether the promise set is empty.
+ * @return true if we have explored all promise combinations.
+ */
+bool Node::promise_empty() const
+{
+ for (int i = resolve_promise_idx + 1; i < (int)resolve_promise.size(); i++)
+ if (i >= 0 && resolve_promise[i])
+ return false;
+ return true;
+}
+
+/** @brief Clear any promise-resolution information for this Node */
+void Node::clear_promise_resolutions()
+{
+ resolve_promise.clear();
+ resolve_promise_idx = -1;
+}
+
+/******************************* end promise **********************************/
+
+void Node::set_misc_max(int i)
+{
+ misc_max = i;
+}
+
+int Node::get_misc() const
+{
+ return misc_index;
+}
+
+bool Node::increment_misc()
+{
+ return (misc_index < misc_max) && ((++misc_index) < misc_max);
+}
+
+bool Node::misc_empty() const
+{
+ return (misc_index + 1) >= misc_max;
+}
+
+bool Node::is_enabled(Thread *t) const
+{
+ int thread_id = id_to_int(t->get_id());
+ return thread_id < num_threads && (enabled_array[thread_id] != THREAD_DISABLED);
+}
+
+enabled_type_t Node::enabled_status(thread_id_t tid) const
+{
+ int thread_id = id_to_int(tid);
+ if (thread_id < num_threads)
+ return enabled_array[thread_id];
+ else
+ return THREAD_DISABLED;
+}
+
+bool Node::is_enabled(thread_id_t tid) const
+{
+ int thread_id = id_to_int(tid);
+ return thread_id < num_threads && (enabled_array[thread_id] != THREAD_DISABLED);
+}
+
+bool Node::has_priority(thread_id_t tid) const
+{
+ return fairness[id_to_int(tid)].priority;
+}
+
+bool Node::has_priority_over(thread_id_t tid1, thread_id_t tid2) const
+{
+ return get_yield_data(id_to_int(tid1), id_to_int(tid2)) & YIELD_P;
+}
+
+/*********************************** read from ********************************/
+
+/**
+ * Get the current state of the may-read-from set iteration
+ * @return The read-from type we should currently be checking (past or future)
+ */
+read_from_type_t Node::get_read_from_status()
+{
+ if (read_from_status == READ_FROM_PAST && read_from_past.empty())
+ increment_read_from();
+ return read_from_status;
+}
+
+/**
+ * Iterate one step in the may-read-from iteration. This includes a step in
+ * reading from the either the past or the future.
+ * @return True if there is a new read-from to explore; false otherwise
+ */
+bool Node::increment_read_from()
+{
+ clear_promise_resolutions();
+ if (increment_read_from_past()) {
+ read_from_status = READ_FROM_PAST;
+ return true;
+ } else if (increment_read_from_promise()) {
+ read_from_status = READ_FROM_PROMISE;
+ return true;
+ } else if (increment_future_value()) {
+ read_from_status = READ_FROM_FUTURE;
+ return true;
}
- explored_children[i] = true;
+ read_from_status = READ_FROM_NONE;
+ return false;
+}
+
+/**
+ * @return True if there are any new read-froms to explore
+ */
+bool Node::read_from_empty() const
+{
+ return read_from_past_empty() &&
+ read_from_promise_empty() &&
+ future_value_empty();
}
-static void clear_node_list(node_list_t *list, node_list_t::iterator start,
- node_list_t::iterator end)
+/**
+ * Get the total size of the may-read-from set, including both past and future
+ * values
+ * @return The size of may-read-from
+ */
+unsigned int Node::read_from_size() const
{
- node_list_t::iterator it;
+ return read_from_past.size() +
+ read_from_promises.size() +
+ future_values.size();
+}
- for (it = start; it != end; it++)
- delete (*it);
- list->erase(start, end);
+/******************************* end read from ********************************/
+
+/****************************** read from past ********************************/
+
+/** @brief Prints info about read_from_past set */
+void Node::print_read_from_past()
+{
+ for (unsigned int i = 0; i < read_from_past.size(); i++)
+ read_from_past[i]->print();
}
-NodeStack::NodeStack()
- : total_nodes(0)
+/**
+ * Add an action to the read_from_past set.
+ * @param act is the action to add
+ */
+void Node::add_read_from_past(const ModelAction *act)
{
- node_list.push_back(new Node());
- total_nodes++;
- iter = node_list.begin();
+ read_from_past.push_back(act);
}
-NodeStack::~NodeStack()
+/**
+ * Gets the next 'read_from_past' action from this Node. Only valid for a node
+ * where this->action is a 'read'.
+ * @return The first element in read_from_past
+ */
+const ModelAction * Node::get_read_from_past() const
{
- clear_node_list(&node_list, node_list.begin(), node_list.end());
+ if (read_from_past_idx < read_from_past.size())
+ return read_from_past[read_from_past_idx];
+ else
+ return NULL;
}
-void NodeStack::print()
+const ModelAction * Node::get_read_from_past(int i) const
{
- node_list_t::iterator it;
- printf("............................................\n");
- printf("NodeStack printing node_list:\n");
- for (it = node_list.begin(); it != node_list.end(); it++) {
- if (it == this->iter)
- printf("vvv following action is the current iterator vvv\n");
- (*it)->print();
+ return read_from_past[i];
+}
+
+int Node::get_read_from_past_size() const
+{
+ return read_from_past.size();
+}
+
+/**
+ * Checks whether the readsfrom set for this node is empty.
+ * @return true if the readsfrom set is empty.
+ */
+bool Node::read_from_past_empty() const
+{
+ return ((read_from_past_idx + 1) >= read_from_past.size());
+}
+
+/**
+ * Increments the index into the readsfrom set to explore the next item.
+ * @return Returns false if we have explored all items.
+ */
+bool Node::increment_read_from_past()
+{
+ DBG();
+ if (read_from_past_idx < read_from_past.size()) {
+ read_from_past_idx++;
+ return read_from_past_idx < read_from_past.size();
}
- printf("............................................\n");
+ return false;
+}
+
+/************************** end read from past ********************************/
+
+/***************************** read_from_promises *****************************/
+
+/**
+ * Add an action to the read_from_promises set.
+ * @param reader The read which generated the Promise; we use the ModelAction
+ * instead of the Promise because the Promise does not last across executions
+ */
+void Node::add_read_from_promise(const ModelAction *reader)
+{
+ read_from_promises.push_back(reader);
+}
+
+/**
+ * Gets the next 'read-from-promise' from this Node. Only valid for a node
+ * where this->action is a 'read'.
+ * @return The current element in read_from_promises
+ */
+Promise * Node::get_read_from_promise() const
+{
+ ASSERT(read_from_promise_idx >= 0 && read_from_promise_idx < ((int)read_from_promises.size()));
+ return read_from_promises[read_from_promise_idx]->get_reads_from_promise();
+}
+
+/**
+ * Gets a particular 'read-from-promise' form this Node. Only vlaid for a node
+ * where this->action is a 'read'.
+ * @param i The index of the Promise to get
+ * @return The Promise at index i, if the Promise is still available; NULL
+ * otherwise
+ */
+Promise * Node::get_read_from_promise(int i) const
+{
+ return read_from_promises[i]->get_reads_from_promise();
+}
+
+/** @return The size of the read-from-promise set */
+int Node::get_read_from_promise_size() const
+{
+ return read_from_promises.size();
+}
+
+/**
+ * Checks whether the read_from_promises set for this node is empty.
+ * @return true if the read_from_promises set is empty.
+ */
+bool Node::read_from_promise_empty() const
+{
+ return ((read_from_promise_idx + 1) >= ((int)read_from_promises.size()));
}
-ModelAction * NodeStack::explore_action(ModelAction *act)
+/**
+ * Increments the index into the read_from_promises set to explore the next item.
+ * @return Returns false if we have explored all promises.
+ */
+bool Node::increment_read_from_promise()
{
DBG();
+ if (read_from_promise_idx < ((int)read_from_promises.size())) {
+ read_from_promise_idx++;
+ return (read_from_promise_idx < ((int)read_from_promises.size()));
+ }
+ return false;
+}
+
+/************************* end read_from_promises *****************************/
- ASSERT(!node_list.empty());
+/****************************** future values *********************************/
- if (get_head()->has_been_explored(act->get_tid())) {
- iter++;
- return (*iter)->get_action();
+/**
+ * Adds a value from a weakly ordered future write to backtrack to. This
+ * operation may "fail" if the future value has already been run (within some
+ * sloppiness window of this expiration), or if the futurevalues set has
+ * reached its maximum.
+ * @see model_params.maxfuturevalues
+ *
+ * @param value is the value to backtrack to.
+ * @return True if the future value was successully added; false otherwise
+ */
+bool Node::add_future_value(struct future_value fv)
+{
+ uint64_t value = fv.value;
+ modelclock_t expiration = fv.expiration;
+ thread_id_t tid = fv.tid;
+ int idx = -1; /* Highest index where value is found */
+ for (unsigned int i = 0; i < future_values.size(); i++) {
+ if (future_values[i].value == value && future_values[i].tid == tid) {
+ if (expiration <= future_values[i].expiration)
+ return false;
+ idx = i;
+ }
+ }
+ if (idx > future_index) {
+ /* Future value hasn't been explored; update expiration */
+ future_values[idx].expiration = expiration;
+ return true;
+ } else if (idx >= 0 && expiration <= future_values[idx].expiration + model->params.expireslop) {
+ /* Future value has been explored and is within the "sloppy" window */
+ return false;
}
- /* Diverging from previous execution; clear out remainder of list */
- node_list_t::iterator it = iter;
- it++;
- clear_node_list(&node_list, it, node_list.end());
+ /* Limit the size of the future-values set */
+ if (model->params.maxfuturevalues > 0 &&
+ (int)future_values.size() >= model->params.maxfuturevalues)
+ return false;
+
+ future_values.push_back(fv);
+ return true;
+}
+
+/**
+ * Gets the next 'future_value' from this Node. Only valid for a node where
+ * this->action is a 'read'.
+ * @return The first element in future_values
+ */
+struct future_value Node::get_future_value() const
+{
+ ASSERT(future_index >= 0 && future_index < ((int)future_values.size()));
+ return future_values[future_index];
+}
+
+/**
+ * Checks whether the future_values set for this node is empty.
+ * @return true if the future_values set is empty.
+ */
+bool Node::future_value_empty() const
+{
+ return ((future_index + 1) >= ((int)future_values.size()));
+}
+
+/**
+ * Increments the index into the future_values set to explore the next item.
+ * @return Returns false if we have explored all values.
+ */
+bool Node::increment_future_value()
+{
+ DBG();
+ if (future_index < ((int)future_values.size())) {
+ future_index++;
+ return (future_index < ((int)future_values.size()));
+ }
+ return false;
+}
+
+/************************** end future values *********************************/
+
+/*********************** breaking release sequences ***************************/
+
+/**
+ * Add a write ModelAction to the set of writes that may break the release
+ * sequence. This is used during replay exploration of pending release
+ * sequences. This Node must correspond to a release sequence fixup action.
+ *
+ * @param write The write that may break the release sequence. NULL means we
+ * allow the release sequence to synchronize.
+ */
+void Node::add_relseq_break(const ModelAction *write)
+{
+ relseq_break_writes.push_back(write);
+}
+
+/**
+ * Get the write that may break the current pending release sequence,
+ * according to the replay / divergence pattern.
+ *
+ * @return A write that may break the release sequence. If NULL, that means
+ * the release sequence should not be broken.
+ */
+const ModelAction * Node::get_relseq_break() const
+{
+ if (relseq_break_index < (int)relseq_break_writes.size())
+ return relseq_break_writes[relseq_break_index];
+ else
+ return NULL;
+}
+
+/**
+ * Increments the index into the relseq_break_writes set to explore the next
+ * item.
+ * @return Returns false if we have explored all values.
+ */
+bool Node::increment_relseq_break()
+{
+ DBG();
+ if (relseq_break_index < ((int)relseq_break_writes.size())) {
+ relseq_break_index++;
+ return (relseq_break_index < ((int)relseq_break_writes.size()));
+ }
+ return false;
+}
+
+/**
+ * @return True if all writes that may break the release sequence have been
+ * explored
+ */
+bool Node::relseq_break_empty() const
+{
+ return ((relseq_break_index + 1) >= ((int)relseq_break_writes.size()));
+}
+
+/******************* end breaking release sequences ***************************/
+
+/**
+ * Increments some behavior's index, if a new behavior is available
+ * @return True if there is a new behavior available; otherwise false
+ */
+bool Node::increment_behaviors()
+{
+ /* satisfy a different misc_index values */
+ if (increment_misc())
+ return true;
+ /* satisfy a different set of promises */
+ if (increment_promise())
+ return true;
+ /* read from a different value */
+ if (increment_read_from())
+ return true;
+ /* resolve a release sequence differently */
+ if (increment_relseq_break())
+ return true;
+ return false;
+}
+
+NodeStack::NodeStack() :
+ node_list(),
+ head_idx(-1),
+ total_nodes(0)
+{
+ total_nodes++;
+}
+
+NodeStack::~NodeStack()
+{
+ for (unsigned int i = 0; i < node_list.size(); i++)
+ delete node_list[i];
+}
+
+void NodeStack::print() const
+{
+ model_print("............................................\n");
+ model_print("NodeStack printing node_list:\n");
+ for (unsigned int it = 0; it < node_list.size(); it++) {
+ if ((int)it == this->head_idx)
+ model_print("vvv following action is the current iterator vvv\n");
+ node_list[it]->print();
+ }
+ model_print("............................................\n");
+}
+
+/** Note: The is_enabled set contains what actions were enabled when
+ * act was chosen. */
+ModelAction * NodeStack::explore_action(ModelAction *act, enabled_type_t *is_enabled)
+{
+ DBG();
+
+ if ((head_idx + 1) < (int)node_list.size()) {
+ head_idx++;
+ return node_list[head_idx]->get_action();
+ }
/* Record action */
- get_head()->explore_child(act);
- node_list.push_back(new Node(act, model->get_num_threads()));
+ Node *head = get_head();
+ Node *prevfairness = NULL;
+ if (head) {
+ head->explore_child(act, is_enabled);
+ if (model->params.fairwindow != 0 && head_idx > (int)model->params.fairwindow)
+ prevfairness = node_list[head_idx - model->params.fairwindow];
+ }
+
+ int next_threads = model->get_num_threads();
+ if (act->get_type() == THREAD_CREATE)
+ next_threads++;
+ node_list.push_back(new Node(act, head, next_threads, prevfairness));
total_nodes++;
- iter++;
+ head_idx++;
return NULL;
}
-Node * NodeStack::get_head()
+/**
+ * Empties the stack of all trailing nodes after a given position and calls the
+ * destructor for each. This function is provided an offset which determines
+ * how many nodes (relative to the current replay state) to save before popping
+ * the stack.
+ * @param numAhead gives the number of Nodes (including this Node) to skip over
+ * before removing nodes.
+ */
+void NodeStack::pop_restofstack(int numAhead)
+{
+ /* Diverging from previous execution; clear out remainder of list */
+ unsigned int it = head_idx + numAhead;
+ for (unsigned int i = it; i < node_list.size(); i++)
+ delete node_list[i];
+ node_list.resize(it);
+ node_list.back()->clear_backtracking();
+}
+
+Node * NodeStack::get_head() const
{
- if (node_list.empty())
+ if (node_list.empty() || head_idx < 0)
return NULL;
- return *iter;
+ return node_list[head_idx];
}
-Node * NodeStack::get_next()
+Node * NodeStack::get_next() const
{
- node_list_t::iterator it = iter;
if (node_list.empty()) {
DEBUG("Empty\n");
return NULL;
}
- it++;
- if (it == node_list.end()) {
+ unsigned int it = head_idx + 1;
+ if (it == node_list.size()) {
DEBUG("At end\n");
return NULL;
}
- return *it;
+ return node_list[it];
}
void NodeStack::reset_execution()
{
- iter = node_list.begin();
+ head_idx = -1;
}