#include "snapshot-interface.h"
#include "common.h"
#include "clockvector.h"
+#include "cyclegraph.h"
#define INITIAL_THREAD_ID 0
obj_thrd_map(new std::map<void *, std::vector<action_list_t> >()),
thrd_last_action(new std::vector<ModelAction *>(1)),
node_stack(new NodeStack()),
- next_backtrack(NULL)
+ next_backtrack(NULL),
+ cyclegraph(new CycleGraph())
{
}
delete thrd_last_action;
delete node_stack;
delete scheduler;
+ delete cyclegraph;
}
/**
next = node_stack->get_next()->get_action();
if (next == diverge) {
- Node *node = next->get_node()->get_parent();
-
+ Node *nextnode = next->get_node();
/* Reached divergence point */
+ if (nextnode->increment_read_from()) {
+ /* The next node will read from a different value */
+ tid = next->get_tid();
+ node_stack->pop_restofstack(2);
+ } else {
+ /* Make a different thread execute for next step */
+ Node *node = nextnode->get_parent();
+ tid = node->get_next_backtrack();
+ node_stack->pop_restofstack(1);
+ }
DEBUG("*** Divergence point ***\n");
- tid = node->get_next_backtrack();
diverge = NULL;
- node_stack->pop_restofstack();
} else {
tid = next->get_tid();
}
DBG();
num_executions++;
- print_summary();
+
+ if (isfeasible() || DBG_ENABLED())
+ print_summary();
+
if ((diverge = model->get_next_backtrack()) == NULL)
return false;
void ModelChecker::check_current_action(void)
{
- Node *currnode;
-
ModelAction *curr = this->current_action;
ModelAction *tmp;
current_action = NULL;
nextThread = get_next_replay_thread();
- currnode = curr->get_node()->get_parent();
+ Node *currnode = curr->get_node();
+ Node *parnode = currnode->get_parent();
- if (!currnode->backtrack_empty())
+ if (!parnode->backtrack_empty()||!currnode->readsfrom_empty())
if (!next_backtrack || *curr > *next_backtrack)
next_backtrack = curr;
set_backtracking(curr);
- add_action_to_lists(curr);
-
/* Assign reads_from values */
/* TODO: perform release/acquire synchronization here; include
* reads_from as ModelAction member? */
Thread *th = get_thread(curr->get_tid());
uint64_t value = VALUE_NONE;
if (curr->is_read()) {
- const ModelAction *reads_from = curr->get_node()->get_next_read_from();
+ const ModelAction *reads_from = curr->get_node()->get_read_from();
value = reads_from->get_value();
/* Assign reads_from, perform release/acquire synchronization */
curr->read_from(reads_from);
+ r_modification_order(curr,reads_from);
+ } else if (curr->is_write()) {
+ w_modification_order(curr);
}
+
th->set_return_value(value);
+
+ /* Add action to list last. */
+ add_action_to_lists(curr);
+}
+
+bool ModelChecker::isfeasible() {
+ return !cyclegraph->checkForCycles();
+}
+
+void ModelChecker::r_modification_order(ModelAction * curr, const ModelAction *rf) {
+ std::vector<action_list_t> *thrd_lists = &(*obj_thrd_map)[curr->get_location()];
+ unsigned int i;
+ ASSERT(curr->is_read());
+
+ /* Iterate over all threads */
+ for (i = 0; i < thrd_lists->size(); i++) {
+ /* Iterate over actions in thread, starting from most recent */
+ action_list_t *list = &(*thrd_lists)[i];
+ action_list_t::reverse_iterator rit;
+ for (rit = list->rbegin(); rit != list->rend(); rit++) {
+ ModelAction *act = *rit;
+
+ /* Include at most one act per-thread that "happens before" curr */
+ if (act->happens_before(curr)) {
+ if (act->is_read()) {
+ const ModelAction * prevreadfrom=act->get_reads_from();
+ if (rf!=prevreadfrom)
+ cyclegraph->addEdge(rf, prevreadfrom);
+ } else if (rf!=act) {
+ cyclegraph->addEdge(rf, act);
+ }
+ break;
+ }
+ }
+ }
+}
+
+void ModelChecker::w_modification_order(ModelAction * curr) {
+ std::vector<action_list_t> *thrd_lists = &(*obj_thrd_map)[curr->get_location()];
+ unsigned int i;
+ ASSERT(curr->is_write());
+
+ if (curr->is_seqcst()) {
+ /* We have to at least see the last sequentially consistent write,
+ so we are initialized. */
+ ModelAction * last_seq_cst=get_last_seq_cst(curr->get_location());
+ if (last_seq_cst!=NULL)
+ cyclegraph->addEdge(curr, last_seq_cst);
+ }
+
+ /* Iterate over all threads */
+ for (i = 0; i < thrd_lists->size(); i++) {
+ /* Iterate over actions in thread, starting from most recent */
+ action_list_t *list = &(*thrd_lists)[i];
+ action_list_t::reverse_iterator rit;
+ for (rit = list->rbegin(); rit != list->rend(); rit++) {
+ ModelAction *act = *rit;
+
+ /* Include at most one act per-thread that "happens before" curr */
+ if (act->happens_before(curr)) {
+ if (act->is_read()) {
+ cyclegraph->addEdge(curr, act->get_reads_from());
+ } else
+ cyclegraph->addEdge(curr, act);
+ break;
+ }
+ }
+ }
}
/**
{
std::vector<action_list_t> *thrd_lists = &(*obj_thrd_map)[curr->get_location()];
unsigned int i;
-
ASSERT(curr->is_read());
ModelAction *last_seq_cst = NULL;
if (!act->is_write())
continue;
- /* Don't consider more than one seq_cst write */
- if (!act->is_seqcst() || act == last_seq_cst) {
+ /* Don't consider more than one seq_cst write if we are a seq_cst read. */
+ if (!act->is_seqcst() || !curr->is_seqcst() || act == last_seq_cst) {
DEBUG("Adding action to may_read_from:\n");
if (DBG_ENABLED()) {
act->print();
scheduler->print();
+ if (!isfeasible())
+ printf("INFEASIBLE EXECUTION!\n");
print_list(action_trace);
printf("\n");
}