#include "scanalysis.h"
-#include "model.h"
+#include "action.h"
+#include "threads-model.h"
+#include "clockvector.h"
+#include "execution.h"
-SCAnalysis::SCAnalysis() {
+SCAnalysis::SCAnalysis(const ModelExecution *execution) :
+ cvmap(),
+ cyclic(false),
+ badrfset(),
+ lastwrmap(),
+ threadlists(1),
+ execution(execution)
+{
}
-void SCAnalysis::analyze(action_list_t * actions) {
+SCAnalysis::~SCAnalysis() {
+}
+
+void SCAnalysis::print_list(action_list_t *list) {
+ model_print("---------------------------------------------------------------------\n");
+ if (cyclic)
+ model_print("Not SC\n");
+ unsigned int hash = 0;
+
+ for (action_list_t::iterator it = list->begin(); it != list->end(); it++) {
+ const ModelAction *act = *it;
+ if (act->get_seq_number() > 0) {
+ if (badrfset.contains(act))
+ model_print("BRF ");
+ act->print();
+ if (badrfset.contains(act)) {
+ model_print("Desired Rf: %u \n", badrfset.get(act)->get_seq_number());
+ }
+ }
+ hash = hash ^ (hash << 3) ^ ((*it)->hash());
+ }
+ model_print("HASH %u\n", hash);
+ model_print("---------------------------------------------------------------------\n");
+}
+
+void SCAnalysis::analyze(action_list_t *actions) {
+ action_list_t *list = generateSC(actions);
+ check_rf(list);
+ print_list(list);
+}
+
+void SCAnalysis::check_rf(action_list_t *list) {
+ for (action_list_t::iterator it = list->begin(); it != list->end(); it++) {
+ const ModelAction *act = *it;
+ if (act->is_read()) {
+ if (act->get_reads_from() != lastwrmap.get(act->get_location()))
+ badrfset.put(act, lastwrmap.get(act->get_location()));
+ }
+ if (act->is_write())
+ lastwrmap.put(act->get_location(), act);
+ }
+}
+
+bool SCAnalysis::merge(ClockVector *cv, const ModelAction *act, const ModelAction *act2) {
+ ClockVector *cv2 = cvmap.get(act2);
+ if (cv2 == NULL)
+ return true;
+ if (cv2->getClock(act->get_tid()) >= act->get_seq_number() && act->get_seq_number() != 0) {
+ cyclic = true;
+ //refuse to introduce cycles into clock vectors
+ return false;
+ }
+
+ return cv->merge(cv2);
+}
+
+int SCAnalysis::getNextActions(ModelAction ** array) {
+ int count=0;
+
+ for (int t = 0; t <= maxthreads; t++) {
+ action_list_t *tlt = &threadlists[t];
+ if (tlt->empty())
+ continue;
+ ModelAction *act = tlt->front();
+ ClockVector *cv = cvmap.get(act);
+
+ /* Find the earliest in SC ordering */
+ for (int i = 0; i <= maxthreads; i++) {
+ if ( i == t )
+ continue;
+ action_list_t *threadlist = &threadlists[i];
+ if (threadlist->empty())
+ continue;
+ ModelAction *first = threadlist->front();
+ if (cv->synchronized_since(first)) {
+ act = NULL;
+ break;
+ }
+ }
+ if (act != NULL) {
+ array[count++]=act;
+ }
+ }
+ if (count != 0)
+ return count;
+ for (int t = 0; t <= maxthreads; t++) {
+ action_list_t *tlt = &threadlists[t];
+ if (tlt->empty())
+ continue;
+ ModelAction *act = tlt->front();
+ ClockVector *cv = act->get_cv();
+
+ /* Find the earliest in SC ordering */
+ for (int i = 0; i <= maxthreads; i++) {
+ if ( i == t )
+ continue;
+ action_list_t *threadlist = &threadlists[i];
+ if (threadlist->empty())
+ continue;
+ ModelAction *first = threadlist->front();
+ if (cv->synchronized_since(first)) {
+ act = NULL;
+ break;
+ }
+ }
+ if (act != NULL) {
+ array[count++]=act;
+ }
+ }
+
+ ASSERT(count==0 || cyclic);
+
+ return count;
+}
+
+ModelAction * SCAnalysis::pruneArray(ModelAction **array,int count) {
+ /* No choice */
+ if (count == 1)
+ return array[0];
+
+ /* Choose first non-write action */
+ ModelAction *nonwrite=NULL;
+ for(int i=0;i<count;i++) {
+ if (!array[i]->is_write())
+ if (nonwrite==NULL || nonwrite->get_seq_number() > array[i]->get_seq_number())
+ nonwrite = array[i];
+ }
+ if (nonwrite != NULL)
+ return nonwrite;
+ /* Look for non-conflicting action */
+ ModelAction *nonconflict=NULL;
+ for(int a=0;a<count;a++) {
+ ModelAction *act=array[a];
+ for (int i = 0; i <= maxthreads && act != NULL; i++) {
+ thread_id_t tid = int_to_id(i);
+ if (tid == act->get_tid())
+ continue;
+
+ action_list_t *list = &threadlists[id_to_int(tid)];
+ for (action_list_t::iterator rit = list->begin(); rit != list->end(); rit++) {
+ ModelAction *write = *rit;
+ if (!write->is_write())
+ continue;
+ ClockVector *writecv = cvmap.get(write);
+ if (writecv->synchronized_since(act))
+ break;
+ if (write->get_location() == act->get_location()) {
+ //write is sc after act
+ act = NULL;
+ break;
+ }
+ }
+ }
+ if (act != NULL) {
+ if (nonconflict == NULL || nonconflict->get_seq_number() > act->get_seq_number())
+ nonconflict=act;
+ }
+ }
+ return nonconflict;
+}
+
+action_list_t * SCAnalysis::generateSC(action_list_t *list) {
+ int numactions=buildVectors(list);
+ computeCV(list);
+
+ action_list_t *sclist = new action_list_t();
+ ModelAction **array = (ModelAction **)model_calloc(1, (maxthreads + 1) * sizeof(ModelAction *));
+ int * choices = (int *) model_calloc(1, sizeof(int)*numactions);
+ int endchoice = 0;
+ int currchoice = 0;
+ int lastchoice = -1;
+ while (true) {
+ int numActions = getNextActions(array);
+ if (numActions == 0)
+ break;
+ ModelAction * act=pruneArray(array, numActions);
+ if (act == NULL) {
+ if (currchoice < endchoice) {
+ act = array[choices[currchoice]];
+ //check whether there is still another option
+ if ((choices[currchoice]+1)<numActions)
+ lastchoice=currchoice;
+ currchoice++;
+ } else {
+ act = array[0];
+ choices[currchoice]=0;
+ if (numActions>1)
+ lastchoice=currchoice;
+ currchoice++;
+ }
+ }
+ thread_id_t tid = act->get_tid();
+ //remove action
+ threadlists[id_to_int(tid)].pop_front();
+ //add ordering constraints from this choice
+ if (updateConstraints(act)) {
+ //propagate changes if we have them
+ bool prevc=cyclic;
+ computeCV(list);
+ if (!prevc && cyclic) {
+ model_print("ROLLBACK in SC\n");
+ //check whether we have another choice
+ if (lastchoice != -1) {
+ //have to reset everything
+ choices[lastchoice]++;
+ endchoice=lastchoice+1;
+ currchoice=0;
+ lastchoice=-1;
+ reset(list);
+ buildVectors(list);
+ computeCV(list);
+ sclist->clear();
+ continue;
+ }
+ }
+ }
+ //add action to end
+ sclist->push_back(act);
+ }
+ model_free(array);
+ return sclist;
+}
+
+int SCAnalysis::buildVectors(action_list_t *list) {
+ maxthreads = 0;
+ int numactions = 0;
+ for (action_list_t::iterator it = list->begin(); it != list->end(); it++) {
+ ModelAction *act = *it;
+ numactions++;
+ int threadid = id_to_int(act->get_tid());
+ if (threadid > maxthreads) {
+ threadlists.resize(threadid + 1);
+ maxthreads = threadid;
+ }
+ threadlists[threadid].push_back(act);
+ }
+ return numactions;
+}
+
+void SCAnalysis::reset(action_list_t *list) {
+ for (int t = 0; t <= maxthreads; t++) {
+ action_list_t *tlt = &threadlists[t];
+ tlt->clear();
+ }
+ for (action_list_t::iterator it = list->begin(); it != list->end(); it++) {
+ ModelAction *act = *it;
+ delete cvmap.get(act);
+ cvmap.put(act, NULL);
+ }
+
+ cyclic=false;
+}
+
+bool SCAnalysis::updateConstraints(ModelAction *act) {
+ bool changed = false;
+ for (int i = 0; i <= maxthreads; i++) {
+ thread_id_t tid = int_to_id(i);
+ if (tid == act->get_tid())
+ continue;
+
+ action_list_t *list = &threadlists[id_to_int(tid)];
+ for (action_list_t::iterator rit = list->begin(); rit != list->end(); rit++) {
+ ModelAction *write = *rit;
+ if (!write->is_write())
+ continue;
+ ClockVector *writecv = cvmap.get(write);
+ if (writecv->synchronized_since(act))
+ break;
+ if (write->get_location() == act->get_location()) {
+ //write is sc after act
+ merge(writecv, write, act);
+ changed = true;
+ break;
+ }
+ }
+ }
+ return changed;
+}
+
+bool SCAnalysis::processRead(ModelAction *read, ClockVector *cv) {
+ bool changed = false;
+
+ /* Merge in the clock vector from the write */
+ const ModelAction *write = read->get_reads_from();
+ ClockVector *writecv = cvmap.get(write);
+ changed |= merge(cv, read, write) && (*read < *write);
+
+ for (int i = 0; i <= maxthreads; i++) {
+ thread_id_t tid = int_to_id(i);
+ if (tid == read->get_tid())
+ continue;
+ if (tid == write->get_tid())
+ continue;
+ action_list_t *list = execution->get_actions_on_obj(read->get_location(), tid);
+ if (list == NULL)
+ continue;
+ for (action_list_t::reverse_iterator rit = list->rbegin(); rit != list->rend(); rit++) {
+ ModelAction *write2 = *rit;
+ if (!write2->is_write())
+ continue;
+
+ ClockVector *write2cv = cvmap.get(write2);
+ if (write2cv == NULL)
+ continue;
+
+ /* write -sc-> write2 &&
+ write -rf-> R =>
+ R -sc-> write2 */
+ if (write2cv->synchronized_since(write)) {
+ changed |= merge(write2cv, write2, read);
+ }
+
+ //looking for earliest write2 in iteration to satisfy this
+ /* write2 -sc-> R &&
+ write -rf-> R =>
+ write2 -sc-> write */
+ if (cv->synchronized_since(write2)) {
+ changed |= writecv == NULL || merge(writecv, write, write2);
+ break;
+ }
+ }
+ }
+ return changed;
+}
+
+void SCAnalysis::computeCV(action_list_t *list) {
+ bool changed = true;
+ bool firsttime = true;
+ ModelAction **last_act = (ModelAction **)model_calloc(1, (maxthreads + 1) * sizeof(ModelAction *));
+ while (changed) {
+ changed = changed&firsttime;
+ firsttime = false;
+ for (action_list_t::iterator it = list->begin(); it != list->end(); it++) {
+ ModelAction *act = *it;
+ ModelAction *lastact = last_act[id_to_int(act->get_tid())];
+ if (act->is_thread_start())
+ lastact = execution->get_thread(act)->get_creation();
+ last_act[id_to_int(act->get_tid())] = act;
+ ClockVector *cv = cvmap.get(act);
+ if (cv == NULL) {
+ cv = new ClockVector(NULL, act);
+ cvmap.put(act, cv);
+ }
+ if (lastact != NULL) {
+ merge(cv, act, lastact);
+ }
+ if (act->is_thread_join()) {
+ Thread *joinedthr = act->get_thread_operand();
+ ModelAction *finish = execution->get_last_action(joinedthr->get_id());
+ changed |= merge(cv, act, finish);
+ }
+ if (act->is_read()) {
+ changed |= processRead(act, cv);
+ }
+ }
+ /* Reset the last action array */
+ if (changed) {
+ bzero(last_act, (maxthreads + 1) * sizeof(ModelAction *));
+ }
+ }
+ model_free(last_act);
}
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