Robust/src/Analysis/Locality/LocalityAnalysis.java

   1 package Analysis.Locality;
   2
   3 import java.util.*;
   4 import Analysis.CallGraph.CallGraph;
   5 import IR.SymbolTable;
   6 import IR.State;
   7 import IR.TypeUtil;
   8 import IR.MethodDescriptor;
   9 import IR.Flat.*;
  10 import IR.ClassDescriptor;
  11
  12 public class LocalityAnalysis {
  13     State state;
  14     Stack lbtovisit;
  15     Hashtable<LocalityBinding,LocalityBinding> discovered;
  16     Hashtable<LocalityBinding, Set<LocalityBinding>> dependence;
  17     Hashtable<LocalityBinding, Hashtable<FlatNode,Hashtable<TempDescriptor, Integer>>> temptab;
  18     Hashtable<LocalityBinding, Hashtable<FlatNode, Integer>> atomictab;
  19     Hashtable<LocalityBinding, Hashtable<FlatAtomicEnterNode, Set<TempDescriptor>>> tempstosave;
  20     Hashtable<ClassDescriptor, Set<LocalityBinding>> classtolb;
  21
  22     CallGraph callgraph;
  23     TypeUtil typeutil;
  24     public static final Integer LOCAL=new Integer(0);
  25     public static final Integer GLOBAL=new Integer(1);
  26     public static final Integer EITHER=new Integer(2);
  27     public static final Integer CONFLICT=new Integer(3);
  28
  29     public LocalityAnalysis(State state, CallGraph callgraph, TypeUtil typeutil) {
  30         this.typeutil=typeutil;
  31         this.state=state;
  32         this.discovered=new Hashtable<LocalityBinding,LocalityBinding>();
  33         this.dependence=new Hashtable<LocalityBinding, Set<LocalityBinding>>();
  34         this.temptab=new Hashtable<LocalityBinding, Hashtable<FlatNode,Hashtable<TempDescriptor, Integer>>>();
  35         this.atomictab=new Hashtable<LocalityBinding, Hashtable<FlatNode, Integer>>();
  36         this.lbtovisit=new Stack();
  37         this.callgraph=callgraph;
  38         this.tempstosave=new Hashtable<LocalityBinding, Hashtable<FlatAtomicEnterNode, Set<TempDescriptor>>>();
  39         this.classtolb=new Hashtable<ClassDescriptor, Set<LocalityBinding>>();
  40         doAnalysis();
  41     }
  42
  43     /** This method returns a set of LocalityBindings for the parameter class. */
  44
  45     public Set<LocalityBinding> getClassBindings(ClassDescriptor cd) {
  46         return classtolb.get(cd);
  47     }
  48
  49     /** This method returns a set of LocalityBindings.  A
  50      * LocalityBinding specifies a context a method can be invoked in.
  51      * It specifies whether the method is in a transaction and whether
  52      * its parameter objects are locals or globals.  */
  53
  54     public Set<LocalityBinding> getLocalityBindings() {
  55         return discovered.keySet();
  56     }
  57
  58     /** This method returns a hashtable for a given LocalityBinding
  59      * that tells the current local/global status of temps at the each
  60      * node in the flat representation. */
  61
  62     public Hashtable<FlatNode, Hashtable<TempDescriptor, Integer>> getNodeTempInfo(LocalityBinding lb) {
  63         return temptab.get(lb);
  64     }
  65
  66     /** This method returns an hashtable for a given LocalitBinding
  67      * that tells whether a node in the flat represenation is in a
  68      * transaction or not.  Integer values greater than 0 indicate
  69      * that the node is in a transaction and give the nesting depth.
  70      * The outermost AtomicEnterNode will have a value of 1 and the
  71      * outermost AtomicExitNode will have a value of 0. */
  72
  73     public Hashtable<FlatNode, Integer> getAtomic(LocalityBinding lb) {
  74         return atomictab.get(lb);
  75     }
  76
  77     /** This methods returns a hashtable for a given LocalityBinding
  78      * that tells which temps needs to be saved for each
  79      * AtomicEnterNode.  */
  80
  81     public Hashtable<FlatAtomicEnterNode, Set<TempDescriptor>> getTemps(LocalityBinding lb) {
  82         return tempstosave.get(lb);
  83     }
  84
  85     public Set<TempDescriptor> getTempSet(LocalityBinding lb) {
  86         HashSet<TempDescriptor> set=new HashSet<TempDescriptor>();
  87         Hashtable<FlatAtomicEnterNode, Set<TempDescriptor>> table=getTemps(lb);
  88         for(Iterator<FlatAtomicEnterNode> faenit=table.keySet().iterator();faenit.hasNext();) {
  89             FlatAtomicEnterNode faen=faenit.next();
  90             set.addAll(table.get(faen));
  91         }
  92         return set;
  93     }
  94
  95     private void doAnalysis() {
  96         computeLocalityBindings();
  97         computeTempstoSave();
  98     }
  99
 100     private void computeLocalityBindings() {
 101         LocalityBinding lbmain=new LocalityBinding(typeutil.getMain(), false);
 102         lbmain.setGlobal(0, LOCAL);
 103         lbtovisit.add(lbmain);
 104         discovered.put(lbmain, lbmain);
 105         if (!classtolb.containsKey(lbmain.getMethod().getClassDesc()))
 106             classtolb.put(lbmain.getMethod().getClassDesc(), new HashSet<LocalityBinding>());
 107         classtolb.get(lbmain.getMethod().getClassDesc()).add(lbmain);
 108
 109         while(!lbtovisit.empty()) {
 110             LocalityBinding lb=(LocalityBinding) lbtovisit.pop();
 111             Integer returnglobal=lb.getGlobalReturn();
 112             MethodDescriptor md=lb.getMethod();
 113             Hashtable<FlatNode,Hashtable<TempDescriptor, Integer>> temptable=new Hashtable<FlatNode,Hashtable<TempDescriptor, Integer>>();
 114             Hashtable<FlatNode, Integer> atomictable=new Hashtable<FlatNode, Integer>();
 115             computeCallsFlags(md, lb, temptable, atomictable);
 116             atomictab.put(lb, atomictable);
 117             temptab.put(lb, temptable);
 118
 119             if (!md.isStatic()&&!returnglobal.equals(lb.getGlobalReturn())) {
 120                 //return type is more precise now
 121                 //rerun everything that call us
 122                 lbtovisit.addAll(dependence.get(lb));
 123             }
 124         }
 125     }
 126
 127
 128     public void computeCallsFlags(MethodDescriptor md, LocalityBinding lb, Hashtable<FlatNode, Hashtable<TempDescriptor, Integer>> temptable, Hashtable<FlatNode, Integer> atomictable) {
 129         FlatMethod fm=state.getMethodFlat(md);
 130         HashSet<FlatNode> tovisit=new HashSet<FlatNode>();
 131         tovisit.add(fm.getNext(0));
 132         {
 133             // Build table for initial node
 134             Hashtable<TempDescriptor,Integer> table=new Hashtable<TempDescriptor,Integer>();
 135             temptable.put(fm, table);
 136             atomictable.put(fm, lb.isAtomic()?1:0);
 137             int offset=md.isStatic()?0:1;
 138             if (!md.isStatic()) {
 139                 table.put(fm.getParameter(0), lb.getGlobalThis());
 140             }
 141             for(int i=offset;i<fm.numParameters();i++) {
 142                 TempDescriptor temp=fm.getParameter(i);
 143                 Integer b=lb.isGlobal(i-offset);
 144                 table.put(temp,b);
 145             }
 146         }
 147
 148         while(!tovisit.isEmpty()) {
 149             FlatNode fn=tovisit.iterator().next();
 150             tovisit.remove(fn);
 151             Hashtable<TempDescriptor, Integer> currtable=new Hashtable<TempDescriptor, Integer>();
 152             int atomicstate=0;
 153             for(int i=0;i<fn.numPrev();i++) {
 154                 FlatNode prevnode=fn.getPrev(i);
 155                 if (atomictable.containsKey(prevnode)) {
 156                     atomicstate=atomictable.get(prevnode).intValue();
 157                 }
 158                 if (!temptable.containsKey(prevnode))
 159                     continue;
 160                 Hashtable<TempDescriptor, Integer> prevtable=temptable.get(prevnode);
 161                 for(Iterator<TempDescriptor> tempit=prevtable.keySet().iterator();tempit.hasNext();) {
 162                     TempDescriptor temp=tempit.next();
 163                     Integer tmpint=prevtable.get(temp);
 164                     Integer oldint=currtable.containsKey(temp)?currtable.get(temp):EITHER;
 165                     Integer newint=merge(tmpint, oldint);
 166                     currtable.put(temp, newint);
 167                 }
 168             }
 169             atomictable.put(fn, atomicstate);
 170             // Process this node
 171             switch(fn.kind()) {
 172             case FKind.FlatAtomicEnterNode:
 173                 processAtomicEnterNode((FlatAtomicEnterNode)fn, atomictable);
 174                 if (!lb.isAtomic())
 175                     lb.setHasAtomic();
 176                 break;
 177             case FKind.FlatAtomicExitNode:
 178                 processAtomicExitNode((FlatAtomicExitNode)fn, atomictable);
 179                 break;
 180             case FKind.FlatCall:
 181                 processCallNode(lb, (FlatCall)fn, currtable, isAtomic(atomictable, fn));
 182                 break;
 183             case FKind.FlatFieldNode:
 184                 processFieldNode(lb, (FlatFieldNode)fn, isAtomic(atomictable, fn), currtable);
 185                 break;
 186             case FKind.FlatSetFieldNode:
 187                 processSetFieldNode(lb, (FlatSetFieldNode)fn, isAtomic(atomictable,fn), currtable);
 188                 break;
 189             case FKind.FlatNew:
 190                 processNew(lb, (FlatNew)fn, isAtomic(atomictable, fn), currtable);
 191                 break;
 192             case FKind.FlatOpNode:
 193                 processOpNode((FlatOpNode)fn, currtable);
 194                 break;
 195             case FKind.FlatCastNode:
 196                 processCastNode((FlatCastNode)fn, currtable);
 197                 break;
 198             case FKind.FlatLiteralNode:
 199                 processLiteralNode((FlatLiteralNode)fn, currtable);
 200                 break;
 201             case FKind.FlatReturnNode:
 202                 processReturnNode(lb, (FlatReturnNode)fn, currtable);
 203                 break;
 204             case FKind.FlatSetElementNode:
 205                 processSetElementNode(lb, (FlatSetElementNode)fn, currtable, isAtomic(atomictable, fn));
 206                 break;
 207             case FKind.FlatElementNode:
 208                 processElementNode(lb, (FlatElementNode)fn, currtable, isAtomic(atomictable, fn));
 209                 break;
 210             case FKind.FlatCondBranch:
 211             case FKind.FlatBackEdge:
 212             case FKind.FlatNop:
 213                 //No action needed for these
 214                 break;
 215             case FKind.FlatFlagActionNode:
 216             case FKind.FlatCheckNode:
 217             case FKind.FlatTagDeclaration:
 218                 throw new Error("Incompatible with tasks!");
 219             case FKind.FlatMethod:
 220             default:
 221                 throw new Error();
 222             }
 223             Hashtable<TempDescriptor,Integer> oldtable=temptable.get(fn);
 224             if (oldtable==null||!oldtable.equals(currtable)) {
 225                 // Update table for this node
 226                 temptable.put(fn, currtable);
 227                 for(int i=0;i<fn.numNext();i++) {
 228                     tovisit.add(fn.getNext(i));
 229                 }
 230             }
 231         }
 232     }
 233
 234     private static boolean isAtomic(Hashtable<FlatNode, Integer> atomictable, FlatNode fn) {
 235         return atomictable.get(fn).intValue()>0;
 236     }
 237
 238     private static Integer merge(Integer a, Integer b) {
 239         if (a==null||a.equals(EITHER))
 240             return b;
 241         if (b==null||b.equals(EITHER))
 242             return a;
 243         if (a.equals(b))
 244             return a;
 245         return CONFLICT;
 246     }
 247
 248     void processCallNode(LocalityBinding currlb, FlatCall fc, Hashtable<TempDescriptor, Integer> currtable, boolean isatomic) {
 249         MethodDescriptor nodemd=fc.getMethod();
 250         Set methodset=fc.getThis()==null?callgraph.getMethods(nodemd):
 251             callgraph.getMethods(nodemd, fc.getThis().getType());
 252         Integer currreturnval=EITHER; //Start off with the either value
 253         for(Iterator methodit=methodset.iterator();methodit.hasNext();) {
 254             MethodDescriptor md=(MethodDescriptor) methodit.next();
 255             boolean isnative=md.getModifiers().isNative();
 256
 257             LocalityBinding lb=new LocalityBinding(md, isatomic);
 258             if (isnative&&isatomic) {
 259                 System.out.println("Don't call native methods in atomic blocks!");
 260             }
 261             for(int i=0;i<fc.numArgs();i++) {
 262                 TempDescriptor arg=fc.getArg(i);
 263                 if(isnative&&(currtable.get(arg).equals(GLOBAL)||
 264                               currtable.get(arg).equals(CONFLICT)))
 265                    throw new Error("Potential call to native method "+md+" with global parameter:\n"+currlb.getExplanation());
 266                 lb.setGlobal(i,currtable.get(arg));
 267             }
 268             if (fc.getThis()!=null) {
 269                 Integer thistype=currtable.get(fc.getThis());
 270                 if (thistype==null)
 271                     thistype=EITHER;
 272                 if(thistype.equals(CONFLICT))
 273                     throw new Error("Using type that can be either local or global in context:\n"+currlb.getExplanation());
 274                 if(thistype.equals(GLOBAL)&&!isatomic)
 275                     throw new Error("Using global object outside of transaction in context:\n"+currlb.getExplanation());
 276                 if (isnative&&thistype.equals(GLOBAL))
 277                     throw new Error("Potential call to native method "+md+" on global objects:\n"+currlb.getExplanation());
 278                 lb.setGlobalThis(thistype);
 279             } else
 280                 lb.setGlobalThis(EITHER);//default value
 281
 282             //lb is built
 283             if (!discovered.containsKey(lb)) {
 284                 if (isnative)
 285                     lb.setGlobalReturn(LOCAL);
 286                 else
 287                     lb.setGlobalReturn(EITHER);
 288                 lb.setParent(currlb);
 289                 lbtovisit.add(lb);
 290                 discovered.put(lb, lb);
 291                 if (!classtolb.containsKey(lb.getMethod().getClassDesc()))
 292                     classtolb.put(lb.getMethod().getClassDesc(), new HashSet<LocalityBinding>());
 293                 classtolb.get(lb.getMethod().getClassDesc()).add(lb);
 294             } else
 295                 lb=discovered.get(lb);
 296             Integer returnval=lb.getGlobalReturn();
 297             currreturnval=merge(returnval, currreturnval);
 298             if (!dependence.containsKey(lb))
 299                 dependence.put(lb, new HashSet<LocalityBinding>());
 300             dependence.get(lb).add(currlb);
 301         }
 302         if (fc.getReturnTemp()!=null) {
 303             currtable.put(fc.getReturnTemp(), currreturnval);
 304         }
 305     }
 306
 307     void processFieldNode(LocalityBinding lb, FlatFieldNode ffn, boolean transaction, Hashtable<TempDescriptor, Integer> currtable) {
 308         Integer type=currtable.get(ffn.getSrc());
 309         TempDescriptor dst=ffn.getDst();
 310         if (type.equals(LOCAL)) {
 311             if (ffn.getField().isGlobal())
 312                 currtable.put(dst,GLOBAL);
 313             else
 314                 currtable.put(dst,LOCAL);
 315         } else if (type.equals(GLOBAL)) {
 316             if (!transaction)
 317                 throw new Error("Global access outside of a transaction in context:\n"+lb.getExplanation());
 318             if (ffn.getField().getType().isPrimitive())
 319                 currtable.put(dst, LOCAL); // primitives are local
 320             else
 321                 currtable.put(dst, GLOBAL);
 322         } else if (type.equals(EITHER)) {
 323             if (ffn.getField().getType().isPrimitive())
 324                 currtable.put(dst, LOCAL); // primitives are local
 325             else
 326                 currtable.put(dst, EITHER);
 327         } else if (type.equals(CONFLICT)) {
 328             throw new Error("Access to object that could be either global or local in context:\n"+lb.getExplanation());
 329         }
 330     }
 331
 332     //need to handle primitives
 333     void processSetFieldNode(LocalityBinding lb, FlatSetFieldNode fsfn, boolean transaction, Hashtable<TempDescriptor, Integer> currtable) {
 334         Integer srctype=currtable.get(fsfn.getSrc());
 335         Integer dsttype=currtable.get(fsfn.getDst());
 336
 337         if (dsttype.equals(LOCAL)) {
 338             if (fsfn.getField().isGlobal()) {
 339                 if (!(srctype.equals(GLOBAL)||srctype.equals(EITHER)))
 340                     throw new Error("Writing possible local reference to global field in context: \n"+lb.getExplanation());
 341             } else {
 342                 if (!(srctype.equals(LOCAL)||srctype.equals(EITHER)))
 343                     throw new Error("Writing possible global reference to local object in context: \n"+lb.getExplanation());
 344             }
 345         } else if (dsttype.equals(GLOBAL)) {
 346             if (!transaction)
 347                 throw new Error("Global access outside of a transaction in context:\n"+lb.getExplanation());
 348             //okay to store primitives in global object
 349             if (srctype.equals(LOCAL) && fsfn.getField().getType().isPrimitive())
 350                 return;
 351             if (!(srctype.equals(GLOBAL)||srctype.equals(EITHER)))
 352                 throw new Error("Writing possible local reference to global object in context:\n"+lb.getExplanation());
 353         } else if (dsttype.equals(EITHER)) {
 354             if (srctype.equals(CONFLICT))
 355                 throw new Error("Using reference that could be local or global in context:\n"+lb.getExplanation());
 356         } else if (dsttype.equals(CONFLICT)) {
 357             throw new Error("Access to object that could be either global or local in context:\n"+lb.getExplanation());
 358         }
 359     }
 360
 361     void processNew(LocalityBinding lb, FlatNew fn, boolean transaction, Hashtable<TempDescriptor, Integer> currtable) {
 362         if (fn.isGlobal()&&!transaction) {
 363             throw new Error("Allocating global object outside of transaction in context:"+lb.getExplanation());
 364         }
 365         if (fn.isGlobal())
 366             currtable.put(fn.getDst(), GLOBAL);
 367         else
 368             currtable.put(fn.getDst(), LOCAL);
 369     }
 370
 371     void processOpNode(FlatOpNode fon, Hashtable<TempDescriptor, Integer> currtable) {
 372         /* Just propagate value */
 373         currtable.put(fon.getDest(), currtable.get(fon.getLeft()));
 374     }
 375
 376     void processCastNode(FlatCastNode fcn, Hashtable<TempDescriptor, Integer> currtable) {
 377         currtable.put(fcn.getDst(), currtable.get(fcn.getSrc()));
 378     }
 379
 380     void processLiteralNode(FlatLiteralNode fln, Hashtable<TempDescriptor, Integer> currtable) {
 381         //null is either
 382         if (fln.getValue()==null)
 383             currtable.put(fln.getDst(), EITHER);
 384         else
 385             currtable.put(fln.getDst(), LOCAL);
 386     }
 387
 388     void processReturnNode(LocalityBinding lb, FlatReturnNode frn, Hashtable<TempDescriptor, Integer> currtable) {
 389         if(frn.getReturnTemp()!=null) {
 390             Integer returntype=currtable.get(frn.getReturnTemp());
 391             lb.setGlobalReturn(merge(returntype, lb.getGlobalReturn()));
 392         }
 393     }
 394
 395     void processSetElementNode(LocalityBinding lb, FlatSetElementNode fsen, Hashtable<TempDescriptor, Integer> currtable, boolean isatomic) {
 396         Integer srctype=currtable.get(fsen.getSrc());
 397         Integer dsttype=currtable.get(fsen.getDst());
 398
 399         if (dsttype.equals(LOCAL)) {
 400             if (!(srctype.equals(LOCAL)||srctype.equals(EITHER)))
 401                 throw new Error("Writing possible global reference to local object in context:\n"+lb.getExplanation());
 402         } else if (dsttype.equals(GLOBAL)) {
 403             if (!(srctype.equals(GLOBAL)||srctype.equals(EITHER)))
 404                 throw new Error("Writing possible local reference to global object in context:\n"+lb.getExplanation());
 405             if (!isatomic)
 406                 throw new Error("Global access outside of a transaction in context:\n"+lb.getExplanation());
 407         } else if (dsttype.equals(EITHER)) {
 408             if (srctype.equals(CONFLICT))
 409                 throw new Error("Using reference that could be local or global in context:\n"+lb.getExplanation());
 410         } else if (dsttype.equals(CONFLICT)) {
 411             throw new Error("Access to object that could be either global or local in context:\n"+lb.getExplanation());
 412         }
 413     }
 414
 415     void processElementNode(LocalityBinding lb, FlatElementNode fen, Hashtable<TempDescriptor, Integer> currtable, boolean isatomic) {
 416         Integer type=currtable.get(fen.getSrc());
 417         TempDescriptor dst=fen.getDst();
 418         if (type.equals(LOCAL)) {
 419             currtable.put(dst,LOCAL);
 420         } else if (type.equals(GLOBAL)) {
 421             if (!isatomic)
 422                 throw new Error("Global access outside of a transaction in context:\n"+lb.getExplanation());
 423             currtable.put(dst, GLOBAL);
 424         } else if (type.equals(EITHER)) {
 425             currtable.put(dst, EITHER);
 426         } else if (type.equals(CONFLICT)) {
 427             throw new Error("Access to object that could be either global or local in context:\n"+lb.getExplanation());
 428         }
 429     }
 430
 431     void processAtomicEnterNode(FlatAtomicEnterNode fen, Hashtable<FlatNode, Integer> atomictable) {
 432         int atomic=atomictable.get(fen).intValue();
 433         atomictable.put(fen, new Integer(atomic+1));
 434     }
 435
 436     void processAtomicExitNode(FlatAtomicExitNode fen, Hashtable<FlatNode, Integer> atomictable) {
 437         int atomic=atomictable.get(fen).intValue();
 438         atomictable.put(fen, new Integer(atomic-1));
 439     }
 440
 441     private Hashtable<FlatNode, Set<TempDescriptor>> computeLiveTemps(FlatMethod fm) {
 442         Hashtable<FlatNode, Set<TempDescriptor>> nodetotemps=new Hashtable<FlatNode, Set<TempDescriptor>>();
 443
 444         Set<FlatNode> toprocess=fm.getNodeSet();
 445
 446         while(!toprocess.isEmpty()) {
 447             FlatNode fn=toprocess.iterator().next();
 448             toprocess.remove(fn);
 449
 450             List<TempDescriptor> reads=Arrays.asList(fn.readsTemps());
 451             List<TempDescriptor> writes=Arrays.asList(fn.readsTemps());
 452
 453             HashSet<TempDescriptor> tempset=new HashSet<TempDescriptor>();
 454             for(int i=0;i<fn.numNext();i++) {
 455                 FlatNode fnnext=fn.getNext(i);
 456                 if (nodetotemps.containsKey(fnnext))
 457                     tempset.addAll(nodetotemps.get(fnnext));
 458             }
 459             tempset.removeAll(writes);
 460             tempset.addAll(reads);
 461             if (!nodetotemps.containsKey(fn)||
 462                 nodetotemps.get(fn).equals(tempset)) {
 463                 nodetotemps.put(fn, tempset);
 464                 for(int i=0;i<fn.numPrev();i++)
 465                     toprocess.add(fn.getPrev(i));
 466             }
 467         }
 468         return nodetotemps;
 469     }
 470
 471     private void computeTempstoSave() {
 472         for(Iterator<LocalityBinding> lbit=getLocalityBindings().iterator();lbit.hasNext();) {
 473             LocalityBinding lb=lbit.next();
 474             computeTempstoSave(lb);
 475         }
 476     }
 477
 478     /* Need to checkpoint all temps that could be read from along any
 479      * path that are either:
 480        1) Written to by any assignment inside the transaction
 481        2) Read from a global temp.
 482
 483        Generate tempstosave map from
 484        localitybinding->flatatomicenternode->Set<TempDescriptors>
 485     */
 486
 487     private void computeTempstoSave(LocalityBinding lb) {
 488         if (lb.isAtomic())
 489             return;
 490         Hashtable<FlatNode, Integer> atomictab=getAtomic(lb);
 491         Hashtable<FlatNode, Hashtable<TempDescriptor, Integer>> temptab=getNodeTempInfo(lb);
 492         MethodDescriptor md=lb.getMethod();
 493         FlatMethod fm=state.getMethodFlat(md);
 494
 495         Hashtable<FlatNode, Set<TempDescriptor>> nodetotemps=computeLiveTemps(fm);
 496         Hashtable<FlatAtomicEnterNode, Set<TempDescriptor>> nodetosavetemps=new Hashtable<FlatAtomicEnterNode, Set<TempDescriptor>>();
 497         tempstosave.put(lb, nodetosavetemps);
 498
 499         Hashtable<FlatNode, FlatAtomicEnterNode> nodemap=new Hashtable<FlatNode, FlatAtomicEnterNode>();
 500
 501         HashSet<FlatNode> toprocess=new HashSet<FlatNode>();
 502         HashSet<FlatNode> discovered=new HashSet<FlatNode>();
 503         toprocess.add(fm);
 504         discovered.add(fm);
 505         while(!toprocess.isEmpty()) {
 506             FlatNode fn=toprocess.iterator().next();
 507             toprocess.remove(fn);
 508             boolean isatomic=atomictab.get(fn).intValue()>0;
 509             if (isatomic&&
 510                 atomictab.get(fn.getPrev(0)).intValue()==0) {
 511                 assert(fn.getPrev(0).kind()==FKind.FlatAtomicEnterNode);
 512                 nodemap.put(fn, (FlatAtomicEnterNode)fn);
 513                 nodetosavetemps.put((FlatAtomicEnterNode)fn, new HashSet<TempDescriptor>());
 514             } else if (isatomic) {
 515                 FlatAtomicEnterNode atomicnode=nodemap.get(fn);
 516                 Set<TempDescriptor> livetemps=nodetotemps.get(fn);
 517                 List<TempDescriptor> reads=Arrays.asList(fn.readsTemps());
 518                 List<TempDescriptor> writes=Arrays.asList(fn.readsTemps());
 519
 520                 for(Iterator<TempDescriptor> tempit=livetemps.iterator();tempit.hasNext();) {
 521                     TempDescriptor tmp=tempit.next();
 522                     if (writes.contains(tmp)) {
 523                         nodetosavetemps.get(fn).add(tmp);
 524                     } else if (reads.contains(tmp)&&temptab.get(fn).get(tmp)==GLOBAL) {
 525                         nodetosavetemps.get(fn).add(tmp);
 526                     }
 527                 }
 528             }
 529             for(int i=0;i<fn.numNext();i++) {
 530                 FlatNode fnnext=fn.getNext(i);
 531                 if (!discovered.contains(fnnext)) {
 532                     discovered.add(fnnext);
 533                     toprocess.add(fnnext);
 534                     if(isatomic) {
 535                         nodemap.put(fnnext, nodemap.get(fn));
 536                     }
 537                 }
 538             }
 539         }
 540     }
 541 }