thrd_last_fence_release(),
node_stack(node_stack),
priv(new struct model_snapshot_members ()),
- mo_graph(new CycleGraph()),
+ mo_graph(new CycleGraph()),
fuzzer(new Fuzzer())
{
/* Initialize a model-checker thread, for special ModelActions */
* @param rf_set is the set of model actions we can possibly read from
* @return True if processing this read updates the mo_graph.
*/
-void ModelExecution::process_read(ModelAction *curr, SnapVector<const ModelAction *> * rf_set)
+void ModelExecution::process_read(ModelAction *curr, SnapVector<ModelAction *> * rf_set)
{
SnapVector<const ModelAction *> * priorset = new SnapVector<const ModelAction *>();
while(true) {
int index = fuzzer->selectWrite(curr, rf_set);
- const ModelAction *rf = (*rf_set)[index];
+ ModelAction *rf = (*rf_set)[index];
ASSERT(rf);
continue;
/* Establish hypothetical release sequences */
- rel_heads_list_t release_heads;
- get_release_seq_heads(curr, act, &release_heads);
- for (unsigned int i = 0;i < release_heads.size();i++)
- synchronize(release_heads[i], curr);
- if (release_heads.size() != 0)
+ ClockVector *cv = get_hb_from_write(act);
+ if (curr->get_cv()->merge(cv))
updated = true;
}
}
*/
bool ModelExecution::initialize_curr_action(ModelAction **curr)
{
- ModelAction *newcurr;
-
if ((*curr)->is_rmwc() || (*curr)->is_rmw()) {
- newcurr = process_rmw(*curr);
+ ModelAction *newcurr = process_rmw(*curr);
delete *curr;
*curr = newcurr;
return false;
- }
-
- (*curr)->set_seq_number(get_next_seq_num());
-
- newcurr = node_stack->explore_action(*curr);
- if (newcurr) {
- /* First restore type and order in case of RMW operation */
- if ((*curr)->is_rmwr())
- newcurr->copy_typeandorder(*curr);
-
- ASSERT((*curr)->get_location() == newcurr->get_location());
- newcurr->copy_from_new(*curr);
-
- /* Discard duplicate ModelAction; use action from NodeStack */
- delete *curr;
-
- /* Always compute new clock vector */
- newcurr->create_cv(get_parent_action(newcurr->get_tid()));
-
- *curr = newcurr;
- return false; /* Action was explored previously */
} else {
- newcurr = *curr;
+ ModelAction *newcurr = *curr;
+ newcurr->set_seq_number(get_next_seq_num());
+ node_stack->add_action(newcurr);
/* Always compute new clock vector */
newcurr->create_cv(get_parent_action(newcurr->get_tid()));
* @return True if this read established synchronization
*/
-bool ModelExecution::read_from(ModelAction *act, const ModelAction *rf)
+void ModelExecution::read_from(ModelAction *act, ModelAction *rf)
{
ASSERT(rf);
ASSERT(rf->is_write());
act->set_read_from(rf);
if (act->is_acquire()) {
- rel_heads_list_t release_heads;
- get_release_seq_heads(act, act, &release_heads);
- int num_heads = release_heads.size();
- for (unsigned int i = 0;i < release_heads.size();i++)
- if (!synchronize(release_heads[i], act))
- num_heads--;
- return num_heads > 0;
+ ClockVector *cv = get_hb_from_write(rf);
+ if (cv == NULL)
+ return;
+ act->get_cv()->merge(cv);
}
- return false;
}
/**
if (!second_part_of_rmw && curr->get_type() != NOOP)
add_action_to_lists(curr);
- SnapVector<const ModelAction *> * rf_set = NULL;
+ SnapVector<ModelAction *> * rf_set = NULL;
/* Build may_read_from set for newly-created actions */
if (newly_explored && curr->is_read())
rf_set = build_may_read_from(curr);
}
/**
- * Finds the head(s) of the release sequence(s) containing a given ModelAction.
- * The ModelAction under consideration is expected to be taking part in
- * release/acquire synchronization as an object of the "reads from" relation.
- * Note that this can only provide release sequence support for RMW chains
- * which do not read from the future, as those actions cannot be traced until
- * their "promise" is fulfilled. Similarly, we may not even establish the
- * presence of a release sequence with certainty, as some modification order
- * constraints may be decided further in the future. Thus, this function
- * "returns" two pieces of data: a pass-by-reference vector of @a release_heads
- * and a boolean representing certainty.
+ * Computes the clock vector that happens before propagates from this write.
*
* @param rf The action that might be part of a release sequence. Must be a
* write.
- * @param release_heads A pass-by-reference style return parameter. After
- * execution of this function, release_heads will contain the heads of all the
- * relevant release sequences, if any exists with certainty
- * @return true, if the ModelExecution is certain that release_heads is complete;
- * false otherwise
+ * @return ClockVector of happens before relation.
*/
-bool ModelExecution::release_seq_heads(const ModelAction *rf, rel_heads_list_t *release_heads) const
-{
+ClockVector * ModelExecution::get_hb_from_write(ModelAction *rf) const {
+ SnapVector<const ModelAction *> * processset = NULL;
for ( ;rf != NULL;rf = rf->get_reads_from()) {
ASSERT(rf->is_write());
+ if (!rf->is_rmw() || (rf->is_acquire() && rf->is_release()) || rf->get_rfcv() != NULL)
+ break;
+ if (processset == NULL)
+ processset = new SnapVector<const ModelAction *>();
+ processset->push_back(rf);
+ }
- if (rf->is_release())
- release_heads->push_back(rf);
- else if (rf->get_last_fence_release())
- release_heads->push_back(rf->get_last_fence_release());
- if (!rf->is_rmw())
- break;/* End of RMW chain */
-
- /** @todo Need to be smarter here... In the linux lock
- * example, this will run to the beginning of the program for
- * every acquire. */
- /** @todo The way to be smarter here is to keep going until 1
- * thread has a release preceded by an acquire and you've seen
- * both. */
-
- /* acq_rel RMW is a sufficient stopping condition */
- if (rf->is_acquire() && rf->is_release())
- return true;/* complete */
- };
- ASSERT(rf); // Needs to be real write
-
- if (rf->is_release())
- return true;/* complete */
-
- /* else relaxed write
- * - check for fence-release in the same thread (29.8, stmt. 3)
- * - check modification order for contiguous subsequence
- * -> rf must be same thread as release */
-
- const ModelAction *fence_release = rf->get_last_fence_release();
- /* Synchronize with a fence-release unconditionally; we don't need to
- * find any more "contiguous subsequence..." for it */
- if (fence_release)
- release_heads->push_back(fence_release);
-
- return true; /* complete */
-}
-
-/**
- * An interface for getting the release sequence head(s) with which a
- * given ModelAction must synchronize. This function only returns a non-empty
- * result when it can locate a release sequence head with certainty. Otherwise,
- * it may mark the internal state of the ModelExecution so that it will handle
- * the release sequence at a later time, causing @a acquire to update its
- * synchronization at some later point in execution.
- *
- * @param acquire The 'acquire' action that may synchronize with a release
- * sequence
- * @param read The read action that may read from a release sequence; this may
- * be the same as acquire, or else an earlier action in the same thread (i.e.,
- * when 'acquire' is a fence-acquire)
- * @param release_heads A pass-by-reference return parameter. Will be filled
- * with the head(s) of the release sequence(s), if they exists with certainty.
- * @see ModelExecution::release_seq_heads
- */
-void ModelExecution::get_release_seq_heads(ModelAction *acquire,
- ModelAction *read, rel_heads_list_t *release_heads)
-{
- const ModelAction *rf = read->get_reads_from();
-
- release_seq_heads(rf, release_heads);
+ int i = (processset == NULL) ? 1 : processset->size();
+
+ ClockVector * vec = NULL;
+ for(;i > 0 ;i--) {
+ if (rf->get_rfcv() != NULL) {
+ vec = rf->get_rfcv();
+ } else if (rf->is_acquire() && rf->is_release()) {
+ vec = rf->get_cv();
+ } else if (rf->is_release() && !rf->is_rmw()) {
+ vec = rf->get_cv();
+ } else if (rf->is_release()) {
+ //have rmw that is release and doesn't have a rfcv
+ (vec = new ClockVector(vec, NULL))->merge(rf->get_cv());
+ rf->set_rfcv(vec);
+ } else {
+ //operation that isn't release
+ if (rf->get_last_fence_release()) {
+ if (vec == NULL)
+ vec = rf->get_last_fence_release()->get_cv();
+ else
+ (vec=new ClockVector(vec, NULL))->merge(rf->get_last_fence_release()->get_cv());
+ }
+ rf->set_rfcv(vec);
+ }
+ }
+ if (processset != NULL)
+ delete processset;
+ return vec;
}
/**
* @param curr is the current ModelAction that we are exploring; it must be a
* 'read' operation.
*/
-SnapVector<const ModelAction *> * ModelExecution::build_may_read_from(ModelAction *curr)
+SnapVector<ModelAction *> * ModelExecution::build_may_read_from(ModelAction *curr)
{
SnapVector<action_list_t> *thrd_lists = obj_thrd_map.get(curr->get_location());
unsigned int i;
if (curr->is_seqcst())
last_sc_write = get_last_seq_cst_write(curr);
- SnapVector<const ModelAction *> * rf_set = new SnapVector<const ModelAction *>();
+ SnapVector<ModelAction *> * rf_set = new SnapVector<ModelAction *>();
/* Iterate over all threads */
for (i = 0;i < thrd_lists->size();i++) {
action_list_t *list = &(*thrd_lists)[i];
action_list_t::reverse_iterator rit;
for (rit = list->rbegin();rit != list->rend();rit++) {
- const ModelAction *act = *rit;
+ ModelAction *act = *rit;
/* Only consider 'write' actions */
if (!act->is_write()) {
if (act != curr && act->is_read() && act->happens_before(curr)) {
- const ModelAction *tmp = act->get_reads_from();
+ ModelAction *tmp = act->get_reads_from();
if (((unsigned int) id_to_int(tmp->get_tid()))==i)
act = tmp;
else
projects / c11tester.git / blobdiff