scanalysis.cc

   1 #include "scanalysis.h"
   2 #include "action.h"
   3 #include "threads-model.h"
   4 #include "clockvector.h"
   5
   6 SCAnalysis::SCAnalysis() {
   7         cvmap=new HashTable<const ModelAction *, ClockVector *, uintptr_t, 4>();
   8         cycleset=new HashTable<const ModelAction *, const ModelAction *, uintptr_t, 4>();
   9         threadlists=new SnapVector<action_list_t>(1);
  10 }
  11
  12 SCAnalysis::~SCAnalysis() {
  13         delete cvmap;
  14         delete cycleset;
  15         delete threadlists;
  16 }
  17
  18 void SCAnalysis::print_list(action_list_t *list) {
  19         action_list_t::iterator it;
  20
  21         model_print("---------------------------------------------------------------------\n");
  22
  23         unsigned int hash = 0;
  24
  25         for (it = list->begin(); it != list->end(); it++) {
  26                 const ModelAction *act = *it;
  27                 if (act->get_seq_number() > 0) {
  28                         if (cycleset->contains(act))
  29                                 model_print("CYC");
  30                         act->print();
  31                 }
  32                 hash = hash^(hash<<3)^((*it)->hash());
  33         }
  34         model_print("HASH %u\n", hash);
  35         model_print("---------------------------------------------------------------------\n");
  36 }
  37
  38 void SCAnalysis::analyze(action_list_t * actions) {
  39         buildVectors(actions);
  40         computeCV(actions);
  41         action_list_t *list=generateSC(actions);
  42         print_list(list);
  43 }
  44
  45 bool SCAnalysis::merge(ClockVector * cv, const ModelAction * act, ClockVector *cv2) {
  46         if (cv2->getClock(act->get_tid())>=act->get_seq_number() && act->get_seq_number() != 0) {
  47                 cycleset->put(act, act);
  48         }
  49         return cv->merge(cv2);
  50 }
  51
  52 ModelAction * SCAnalysis::getNextAction() {
  53         ModelAction *act=NULL;
  54         for(int i=0;i<=maxthreads;i++) {
  55                 action_list_t * threadlist=&(*threadlists)[i];
  56                 if (threadlist->empty())
  57                         continue;
  58                 ModelAction *first=threadlist->front();
  59                 if (act==NULL) {
  60                         act=first;
  61                         continue;
  62                 }
  63                 ClockVector *cv=cvmap->get(act);
  64                 if (cv->synchronized_since(first)) {
  65                         act=first;
  66                 }
  67         }
  68         return act;
  69 }
  70
  71 action_list_t * SCAnalysis::generateSC(action_list_t *list) {
  72         action_list_t *sclist=new action_list_t();
  73         while (true) {
  74                 ModelAction * act=getNextAction();
  75                 if (act==NULL)
  76                         break;
  77                 thread_id_t tid=act->get_tid();
  78                 //remove action
  79                 (*threadlists)[id_to_int(tid)].pop_front();
  80                 //add ordering constraints from this choice
  81                 if (updateConstraints(act)) {
  82                         //propagate changes if we have them
  83                         computeCV(list);
  84                 }
  85                 //add action to end
  86                 sclist->push_back(act);
  87         }
  88         return sclist;
  89 }
  90
  91 void SCAnalysis::buildVectors(action_list_t *list) {
  92         maxthreads=0;
  93         for (action_list_t::iterator it = list->begin(); it != list->end(); it++) {
  94                 ModelAction *act = *it;
  95                 int threadid=id_to_int(act->get_tid());
  96                 if (threadid > maxthreads) {
  97                         threadlists->resize(threadid+1);
  98                         maxthreads=threadid;
  99                 }
 100                 (*threadlists)[threadid].push_back(act);
 101         }
 102 }
 103
 104 bool SCAnalysis::updateConstraints(ModelAction *act) {
 105         bool changed=false;
 106         ClockVector *actcv = cvmap->get(act);
 107         for(int i=0;i<=maxthreads;i++) {
 108                 thread_id_t tid=int_to_id(i);
 109                 if (tid==act->get_tid())
 110                         continue;
 111
 112                 action_list_t * list=&(*threadlists)[id_to_int(tid)];
 113                 for (action_list_t::iterator rit = list->begin(); rit != list->end(); rit++) {
 114                         ModelAction *write = *rit;
 115                         if (!write->is_write())
 116                                 continue;
 117                         ClockVector *writecv = cvmap->get(write);
 118                         if (writecv->synchronized_since(act))
 119                                 break;
 120                         if (write->get_location() == act->get_location()) {
 121                                 //write is sc after act
 122                                 merge(writecv, write, actcv);
 123                                 changed=true;
 124                                 break;
 125                         }
 126                 }
 127         }
 128         return changed;
 129 }
 130
 131 bool SCAnalysis::processRead(ModelAction *read, ClockVector *cv) {
 132         bool changed=false;
 133
 134         /* Merge in the clock vector from the write */
 135         const ModelAction *write=read->get_reads_from();
 136         ClockVector *writecv=cvmap->get(write);
 137         changed|= ( writecv == NULL || merge(cv, read, writecv) && (*read < *write));
 138
 139         for(int i=0;i<=maxthreads;i++) {
 140                 thread_id_t tid=int_to_id(i);
 141                 if (tid==read->get_tid())
 142                         continue;
 143                 if (tid==write->get_tid())
 144                         continue;
 145                 action_list_t * list=model->get_actions_on_obj(read->get_location(), tid);
 146                 if (list==NULL)
 147                         continue;
 148                 for (action_list_t::reverse_iterator rit = list->rbegin(); rit != list->rend(); rit++) {
 149                         ModelAction *write2 = *rit;
 150                         if (!write2->is_write())
 151                                 continue;
 152
 153                         ClockVector *write2cv = cvmap->get(write2);
 154                         if (write2cv == NULL)
 155                                 continue;
 156
 157                         /* write -sc-> write2 &&
 158                                  write -rf-> R =>
 159                                  R -sc-> write2 */
 160                         if (write2cv->synchronized_since(write)) {
 161                                 changed |= merge(write2cv, write2, cv);
 162                         }
 163
 164                         //looking for earliest write2 in iteration to satisfy this
 165                         /* write2 -sc-> R &&
 166                                  write -rf-> R =>
 167                                  write2 -sc-> write */
 168                         if (cv->synchronized_since(write2)) {
 169                                 changed |= writecv == NULL || merge(writecv, write, write2cv);
 170                                 break;
 171                         }
 172                 }
 173         }
 174         return changed;
 175 }
 176
 177
 178 void SCAnalysis::computeCV(action_list_t *list) {
 179         bool changed=true;
 180         bool firsttime=true;
 181         ModelAction **last_act=(ModelAction **)model_calloc(1,(maxthreads+1)*sizeof(ModelAction *));
 182         while(changed) {
 183                 changed=changed&firsttime;
 184                 firsttime=false;
 185
 186                 for (action_list_t::iterator it = list->begin(); it != list->end(); it++) {
 187                         ModelAction *act = *it;
 188                         ModelAction *lastact = last_act[id_to_int(act->get_tid())];
 189                         if (act->is_thread_start())
 190                                 lastact=model->get_thread(act)->get_creation();
 191                         ClockVector *lastcv=(lastact != NULL) ? cvmap->get(lastact) : NULL;
 192                         last_act[id_to_int(act->get_tid())]=act;
 193                         ClockVector *cv=cvmap->get(act);
 194                         if ( cv == NULL ) {
 195                                 cv = new ClockVector(lastcv, act);
 196                                 cvmap->put(act, cv);
 197                         } else if ( lastcv != NULL ) {
 198                                 merge(cv, act, lastcv);
 199                         }
 200                         if (act->is_thread_join()) {
 201                                 Thread *joinedthr = act->get_thread_operand();
 202                                 ModelAction *finish = model->get_last_action(joinedthr->get_id());
 203                                 ClockVector *finishcv = cvmap->get(finish);
 204                                 changed |= (finishcv == NULL) || merge(cv, act, finishcv);
 205                         }
 206                         if (act->is_thread_join()) {
 207                                 Thread *joinedthr = act->get_thread_operand();
 208                                 ModelAction *finish = model->get_last_action(joinedthr->get_id());
 209                                 ClockVector *finishcv = cvmap->get(finish);
 210                                 changed |= (finishcv == NULL) || cv->merge(finishcv);
 211                         }
 212                         if (act->is_read()) {
 213                                 changed|=processRead(act, cv);
 214                         }
 215                 }
 216                 /* Reset the last action array */
 217                 if (changed) {
 218                         bzero(last_act, (maxthreads+1)*sizeof(ModelAction *));
 219                 }
 220         }
 221         model_free(last_act);
 222 }