ModelChecker *model;
+struct bug_message {
+ bug_message(const char *str) {
+ const char *fmt = " [BUG] %s\n";
+ msg = (char *)snapshot_malloc(strlen(fmt) + strlen(str));
+ sprintf(msg, fmt, str);
+ }
+ ~bug_message() { if (msg) snapshot_free(msg); }
+
+ char *msg;
+ void print() { printf("%s", msg); }
+};
+
/**
* Structure for holding small ModelChecker members that should be snapshotted
*/
modelclock_t used_sequence_numbers;
Thread *nextThread;
ModelAction *next_backtrack;
+ std::vector< bug_message *, SnapshotAlloc<bug_message *> > bugs;
};
/** @brief Constructor */
bad_synchronization(false)
{
/* Allocate this "size" on the snapshotting heap */
- priv = (struct model_snapshot_members *)calloc(1, sizeof(*priv));
+ priv = (struct model_snapshot_members *)snapshot_calloc(1, sizeof(*priv));
/* First thread created will have id INITIAL_THREAD_ID */
priv->next_thread_id = INITIAL_THREAD_ID;
delete node_stack;
delete scheduler;
delete mo_graph;
+
+ for (unsigned int i = 0; i < priv->bugs.size(); i++)
+ delete priv->bugs[i];
+ priv->bugs.clear();
+ snapshot_free(priv);
}
static action_list_t * get_safe_ptr_action(HashTable<const void *, action_list_t *, uintptr_t, 4> * hash, void * ptr) {
return blocking_threads;
}
+/**
+ * Check if this is a complete execution. That is, have all thread completed
+ * execution (rather than exiting because sleep sets have forced a redundant
+ * execution).
+ *
+ * @return True if the execution is complete.
+ */
+bool ModelChecker::is_complete_execution() const
+{
+ for (unsigned int i = 0; i < get_num_threads(); i++)
+ if (is_enabled(int_to_id(i)))
+ return false;
+ return true;
+}
+
+/**
+ * @brief Assert a bug in the executing program.
+ *
+ * Use this function to assert any sort of bug in the user program. If the
+ * current trace is feasible (actually, a prefix of some feasible execution),
+ * then this execution will be aborted, printing the appropriate message. If
+ * the current trace is not yet feasible, the error message will be stashed and
+ * printed if the execution ever becomes feasible.
+ *
+ * This function can also be used to immediately trigger the bug; that is, we
+ * don't wait for a feasible execution before aborting. Only use the
+ * "immediate" option when you know that the infeasibility is justified (e.g.,
+ * pending release sequences are not a problem)
+ *
+ * @param msg Descriptive message for the bug (do not include newline char)
+ * @param user_thread Was this assertion triggered from a user thread?
+ * @param immediate Should this bug be triggered immediately?
+ */
+void ModelChecker::assert_bug(const char *msg, bool user_thread, bool immediate)
+{
+ priv->bugs.push_back(new bug_message(msg));
+
+ if (immediate || isfeasibleprefix()) {
+ set_assert();
+ if (user_thread)
+ switch_to_master(NULL);
+ }
+}
+
+/**
+ * @brief Assert a bug in the executing program, with a default message
+ * @see ModelChecker::assert_bug
+ * @param user_thread Was this assertion triggered from a user thread?
+ */
+void ModelChecker::assert_bug(bool user_thread)
+{
+ assert_bug("bug detected", user_thread);
+}
+
+/**
+ * @brief Assert a bug in the executing program immediately
+ * @see ModelChecker::assert_bug
+ * @param msg Descriptive message for the bug (do not include newline char)
+ */
+void ModelChecker::assert_bug_immediate(const char *msg)
+{
+ printf("Feasible: %s\n", isfeasibleprefix() ? "yes" : "no");
+ assert_bug(msg, false, true);
+}
+
+/** @return True, if any bugs have been reported for this execution */
+bool ModelChecker::have_bug_reports() const
+{
+ return priv->bugs.size() != 0;
+}
+
+/** @brief Print bug report listing for this execution (if any bugs exist) */
+void ModelChecker::print_bugs() const
+{
+ if (have_bug_reports()) {
+ printf("Bug report: %zu bugs detected\n", priv->bugs.size());
+ for (unsigned int i = 0; i < priv->bugs.size(); i++)
+ priv->bugs[i]->print();
+ }
+}
+
/**
* Queries the model-checker for more executions to explore and, if one
* exists, resets the model-checker state to execute a new execution.
num_executions++;
- if (is_deadlocked())
- printf("ERROR: DEADLOCK\n");
- if (isfinalfeasible()) {
+ if (isfinalfeasible() && (is_complete_execution() || have_bug_reports())) {
printf("Earliest divergence point since last feasible execution:\n");
if (earliest_diverge)
earliest_diverge->print();
earliest_diverge = NULL;
num_feasible_executions++;
- }
-
- DEBUG("Number of acquires waiting on pending release sequences: %zu\n",
- pending_rel_seqs->size());
+ if (is_deadlocked())
+ assert_bug("Deadlock detected");
- if (isfinalfeasible() || DBG_ENABLED()) {
+ print_bugs();
checkDataRaces();
print_summary();
+ } else if (DBG_ENABLED()) {
+ print_summary();
}
if ((diverge = get_next_backtrack()) == NULL)
}
//otherwise fall into the lock case
case ATOMIC_LOCK: {
- if (curr->get_cv()->getClock(state->alloc_tid) <= state->alloc_clock) {
- printf("Lock access before initialization\n");
- set_assert();
- }
+ if (curr->get_cv()->getClock(state->alloc_tid) <= state->alloc_clock)
+ assert_bug("Lock access before initialization");
state->islocked = true;
ModelAction *unlock = get_last_unlock(curr);
//synchronize with the previous unlock statement
/* See if we have realized a data race */
if (checkDataRaces())
- set_assert();
+ assert_bug("Datarace");
}
/**
}
}
-bool ModelChecker::promises_expired() {
+bool ModelChecker::promises_expired() const
+{
for (unsigned int promise_index = 0; promise_index < promises->size(); promise_index++) {
Promise *promise = (*promises)[promise_index];
if (promise->get_expiration()<priv->used_sequence_numbers) {
/** @return whether the current partial trace must be a prefix of a
* feasible trace. */
-bool ModelChecker::isfeasibleprefix() {
+bool ModelChecker::isfeasibleprefix() const
+{
return promises->size() == 0 && pending_rel_seqs->size() == 0 && isfeasible();
}
/** @return whether the current partial trace is feasible. */
-bool ModelChecker::isfeasible() {
+bool ModelChecker::isfeasible() const
+{
if (DBG_ENABLED() && mo_graph->checkForRMWViolation())
DEBUG("Infeasible: RMW violation\n");
/** @return whether the current partial trace is feasible other than
* multiple RMW reading from the same store. */
-bool ModelChecker::isfeasibleotherthanRMW() {
+bool ModelChecker::isfeasibleotherthanRMW() const
+{
if (DBG_ENABLED()) {
if (mo_graph->checkForCycles())
DEBUG("Infeasible: modification order cycles\n");
}
/** Returns whether the current completed trace is feasible. */
-bool ModelChecker::isfinalfeasible() {
+bool ModelChecker::isfinalfeasible() const
+{
if (DBG_ENABLED() && promises->size() != 0)
DEBUG("Infeasible: unrevolved promises\n");
}
// If we resolved promises or data races, see if we have realized a data race.
- if (checkDataRaces()) {
- set_assert();
- }
+ if (checkDataRaces())
+ assert_bug("Datarace");
return updated;
}
/* Infeasible -> don't take any more steps */
if (!isfeasible())
return false;
+ else if (isfeasibleprefix() && have_bug_reports()) {
+ set_assert();
+ return false;
+ }
if (params.bound != 0) {
if (priv->used_sequence_numbers > params.bound) {
projects / model-checker.git / blobdiff