obj_map(new HashTable<const void *, action_list_t, uintptr_t, 4>()),
obj_thrd_map(new HashTable<void *, std::vector<action_list_t>, uintptr_t, 4 >()),
promises(new std::vector<Promise *>()),
+ futurevalues(new std::vector<struct PendingFutureValue>()),
lazy_sync_with_release(new HashTable<void *, std::list<ModelAction *>, uintptr_t, 4>()),
thrd_last_action(new std::vector<ModelAction *>(1)),
node_stack(new NodeStack()),
mo_graph(new CycleGraph()),
failed_promise(false),
too_many_reads(false),
- asserted(false),
- rmw_cycle(false)
+ asserted(false)
{
/* Allocate this "size" on the snapshotting heap */
priv = (struct model_snapshot_members *)calloc(1, sizeof(*priv));
node_stack->reset_execution();
failed_promise = false;
too_many_reads = false;
- rmw_cycle=false;
reset_asserted();
snapshotObject->backTrackBeforeStep(0);
}
return next;
}
-
-/** Checks whether making the ModelAction read read_from the
- ModelAction write will introduce a cycle in the reads_from
- relation.
-
-@return true if making it read from will be fine, false otherwise.
-
-*/
-
-bool ModelChecker::ensure_rmw_acyclic(const ModelAction * read, const ModelAction *write) {
- if (!read->is_rmw())
- return true;
- if (!write->is_rmw())
- return true;
- while(write!=NULL) {
- if (write==read) {
- rmw_cycle=true;
- return false;
- }
- write=write->get_reads_from();
- }
- return true;
-}
-
/**
* Processes a read or rmw model action.
* @param curr is the read model action to process.
* @param second_part_of_rmw is boolean that is true is this is the second action of a rmw.
* @return True if processing this read updates the mo_graph.
*/
-
bool ModelChecker::process_read(ModelAction *curr, Thread * th, bool second_part_of_rmw) {
uint64_t value;
- bool updated=false;
- while(true) {
+ bool updated = false;
+ while (true) {
const ModelAction *reads_from = curr->get_node()->get_read_from();
if (reads_from != NULL) {
mo_graph->startChanges();
value = reads_from->get_value();
- /* Assign reads_from, perform release/acquire synchronization */
- if (ensure_rmw_acyclic(curr, reads_from))
- curr->read_from(reads_from);
+ bool r_status = false;
+
if (!second_part_of_rmw) {
check_recency(curr,false);
+ r_status = r_modification_order(curr, reads_from);
}
- bool r_status=r_modification_order(curr,reads_from);
- if (!second_part_of_rmw&&!isfeasible()&&(curr->get_node()->increment_read_from()||!curr->get_node()->future_value_empty())) {
+ if (!second_part_of_rmw&&!isfeasible()&&(curr->get_node()->increment_read_from()||curr->get_node()->increment_future_value())) {
mo_graph->rollbackChanges();
- too_many_reads=false;
+ too_many_reads = false;
continue;
}
+ curr->read_from(reads_from);
mo_graph->commitChanges();
updated |= r_status;
} else if (!second_part_of_rmw) {
}
/* Thread specific actions */
- switch(curr->get_type()) {
+ switch (curr->get_type()) {
case THREAD_CREATE: {
Thread *th = (Thread *)curr->get_location();
th->set_creation(curr);
bool updated = false;
if (curr->is_read()) {
- updated=process_read(curr, th, second_part_of_rmw);
+ updated = process_read(curr, th, second_part_of_rmw);
}
if (curr->is_write()) {
- bool updated_mod_order=w_modification_order(curr);
- bool updated_promises=resolve_promises(curr);
- updated=updated_mod_order|updated_promises;
+ bool updated_mod_order = w_modification_order(curr);
+ bool updated_promises = resolve_promises(curr);
+ updated = updated_mod_order|updated_promises;
+
+ if (promises->size()==0) {
+ for (unsigned int i = 0; i<futurevalues->size(); i++) {
+ struct PendingFutureValue pfv=(*futurevalues)[i];
+ if (pfv.act->get_node()->add_future_value(pfv.value, pfv.expiration) &&
+ (!priv->next_backtrack || *pfv.act > *priv->next_backtrack))
+ priv->next_backtrack = pfv.act;
+ }
+ futurevalues->resize(0);
+ }
mo_graph->commitChanges();
th->set_return_value(VALUE_NONE);
add_action_to_lists(curr);
check_curr_backtracking(curr);
-
+
set_backtracking(curr);
return get_next_thread(curr);
void ModelChecker::check_curr_backtracking(ModelAction * curr) {
Node *currnode = curr->get_node();
Node *parnode = currnode->get_parent();
-
+
if ((!parnode->backtrack_empty() ||
!currnode->read_from_empty() ||
!currnode->future_value_empty() ||
}
}
-
bool ModelChecker::promises_expired() {
for (unsigned int promise_index = 0; promise_index < promises->size(); promise_index++) {
Promise *promise = (*promises)[promise_index];
/** @returns whether the current partial trace is feasible other than
* multiple RMW reading from the same store. */
bool ModelChecker::isfeasibleotherthanRMW() {
- return !mo_graph->checkForCycles() && !failed_promise && !too_many_reads && !rmw_cycle && !promises_expired();
+ return !mo_graph->checkForCycles() && !failed_promise && !too_many_reads && !promises_expired();
}
/** Returns whether the current completed trace is feasible. */
rit++;
}
- action_list_t::reverse_iterator ritcopy=rit;
+ action_list_t::reverse_iterator ritcopy = rit;
//See if we have enough reads from the same value
- int count=0;
+ int count = 0;
for (; count < params.maxreads; rit++,count++) {
if (rit==list->rend())
return;
return;
}
- for (int i=0;i<curr->get_node()->get_read_from_size();i++) {
+ for (int i = 0; i<curr->get_node()->get_read_from_size(); i++) {
//Get write
- const ModelAction * write=curr->get_node()->get_read_from_at(i);
+ const ModelAction * write = curr->get_node()->get_read_from_at(i);
//Need a different write
if (write==curr->get_reads_from())
continue;
/* Test to see whether this is a feasible write to read from*/
mo_graph->startChanges();
r_modification_order(curr, write);
- bool feasiblereadfrom=isfeasible();
+ bool feasiblereadfrom = isfeasible();
mo_graph->rollbackChanges();
if (!feasiblereadfrom)
continue;
- rit=ritcopy;
+ rit = ritcopy;
- bool feasiblewrite=true;
+ bool feasiblewrite = true;
//new we need to see if this write works for everyone
- for (int loop=count;loop>0;loop--,rit++) {
+ for (int loop = count; loop>0; loop--,rit++) {
ModelAction *act=*rit;
- bool foundvalue=false;
- for(int j=0;j<act->get_node()->get_read_from_size();j++) {
+ bool foundvalue = false;
+ for (int j = 0; j<act->get_node()->get_read_from_size(); j++) {
if (act->get_node()->get_read_from_at(i)==write) {
- foundvalue=true;
+ foundvalue = true;
break;
}
}
if (!foundvalue) {
- feasiblewrite=false;
+ feasiblewrite = false;
break;
}
}
/* Include at most one act per-thread that "happens before" curr */
if (act->happens_before(curr)) {
- if (act->is_read()) {
+ if (act->is_write()) {
+ if (rf != act && act != curr) {
+ mo_graph->addEdge(act, rf);
+ added = true;
+ }
+ } else {
const ModelAction *prevreadfrom = act->get_reads_from();
if (prevreadfrom != NULL && rf != prevreadfrom) {
mo_graph->addEdge(prevreadfrom, rf);
added = true;
}
- } else if (rf != act) {
- mo_graph->addEdge(act, rf);
- added = true;
}
+
break;
}
}
if (thin_air_constraint_may_allow(curr, act)) {
if (isfeasible() ||
(curr->is_rmw() && act->is_rmw() && curr->get_reads_from()==act->get_reads_from() && isfeasibleotherthanRMW())) {
- if (act->get_node()->add_future_value(curr->get_value(), curr->get_seq_number()+params.maxfuturedelay) &&
- (!priv->next_backtrack || *act > *priv->next_backtrack))
- priv->next_backtrack = act;
+ struct PendingFutureValue pfv = {curr->get_value(),curr->get_seq_number()+params.maxfuturedelay,act};
+ futurevalues->push_back(pfv);
}
}
}
if (!reader->is_rmw())
return true;
- for(const ModelAction *search=writer->get_reads_from();search!=NULL;search=search->get_reads_from()) {
+ for (const ModelAction *search = writer->get_reads_from(); search != NULL; search = search->get_reads_from()) {
if (search==reader)
return false;
- if (search->get_tid()==reader->get_tid()&&
+ if (search->get_tid() == reader->get_tid() &&
search->happens_before(reader))
break;
}
return true;
}
-
/**
* Finds the head(s) of the release sequence(s) containing a given ModelAction.
* The ModelAction under consideration is expected to be taking part in
Promise *promise = (*promises)[promise_index];
if (write->get_node()->get_promise(i)) {
ModelAction *read = promise->get_action();
- if (ensure_rmw_acyclic(read, write))
- read->read_from(write);
+ read->read_from(write);
if (read->is_rmw()) {
mo_graph->addRMWEdge(write, read);
}
return resolved;
}
-
-
/**
* Compute the set of promises that could potentially be satisfied by this
* action. Note that the set computation actually appears in the Node, not in