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     Hashtable<MethodDescriptor, Set<LocalityBinding>> methodtolb;
  22
  23     CallGraph callgraph;
  24     TypeUtil typeutil;
  25     public static final Integer LOCAL=new Integer(0);
  26     public static final Integer GLOBAL=new Integer(1);
  27     public static final Integer EITHER=new Integer(2);
  28     public static final Integer CONFLICT=new Integer(3);
  29
  30     public LocalityAnalysis(State state, CallGraph callgraph, TypeUtil typeutil) {
  31         this.typeutil=typeutil;
  32         this.state=state;
  33         this.discovered=new Hashtable<LocalityBinding,LocalityBinding>();
  34         this.dependence=new Hashtable<LocalityBinding, Set<LocalityBinding>>();
  35         this.temptab=new Hashtable<LocalityBinding, Hashtable<FlatNode,Hashtable<TempDescriptor, Integer>>>();
  36         this.atomictab=new Hashtable<LocalityBinding, Hashtable<FlatNode, Integer>>();
  37         this.lbtovisit=new Stack();
  38         this.callgraph=callgraph;
  39         this.tempstosave=new Hashtable<LocalityBinding, Hashtable<FlatAtomicEnterNode, Set<TempDescriptor>>>();
  40         this.classtolb=new Hashtable<ClassDescriptor, Set<LocalityBinding>>();
  41         this.methodtolb=new Hashtable<MethodDescriptor, Set<LocalityBinding>>();
  42         doAnalysis();
  43     }
  44
  45     /** This method returns a set of LocalityBindings for the parameter class. */
  46
  47     public Set<LocalityBinding> getClassBindings(ClassDescriptor cd) {
  48         return classtolb.get(cd);
  49     }
  50
  51     /** This method returns a set of LocalityBindings for the parameter method. */
  52
  53     public Set<LocalityBinding> getMethodBindings(MethodDescriptor md) {
  54         return methodtolb.get(md);
  55     }
  56
  57     /** This method returns a set of LocalityBindings.  A
  58      * LocalityBinding specifies a context a method can be invoked in.
  59      * It specifies whether the method is in a transaction and whether
  60      * its parameter objects are locals or globals.  */
  61
  62     public Set<LocalityBinding> getLocalityBindings() {
  63         return discovered.keySet();
  64     }
  65
  66     /** This method returns a hashtable for a given LocalityBinding
  67      * that tells the current local/global status of temps at the each
  68      * node in the flat representation. */
  69
  70     public Hashtable<FlatNode, Hashtable<TempDescriptor, Integer>> getNodeTempInfo(LocalityBinding lb) {
  71         return temptab.get(lb);
  72     }
  73
  74     /** This method returns an hashtable for a given LocalitBinding
  75      * that tells whether a node in the flat represenation is in a
  76      * transaction or not.  Integer values greater than 0 indicate
  77      * that the node is in a transaction and give the nesting depth.
  78      * The outermost AtomicEnterNode will have a value of 1 and the
  79      * outermost AtomicExitNode will have a value of 0. */
  80
  81     public Hashtable<FlatNode, Integer> getAtomic(LocalityBinding lb) {
  82         return atomictab.get(lb);
  83     }
  84
  85     /** This methods returns a hashtable for a given LocalityBinding
  86      * that tells which temps needs to be saved for each
  87      * AtomicEnterNode.  */
  88
  89     public Hashtable<FlatAtomicEnterNode, Set<TempDescriptor>> getTemps(LocalityBinding lb) {
  90         return tempstosave.get(lb);
  91     }
  92
  93     public Set<TempDescriptor> getTempSet(LocalityBinding lb) {
  94         HashSet<TempDescriptor> set=new HashSet<TempDescriptor>();
  95         Hashtable<FlatAtomicEnterNode, Set<TempDescriptor>> table=getTemps(lb);
  96         for(Iterator<FlatAtomicEnterNode> faenit=table.keySet().iterator();faenit.hasNext();) {
  97             FlatAtomicEnterNode faen=faenit.next();
  98             set.addAll(table.get(faen));
  99         }
 100         return set;
 101     }
 102
 103     private void doAnalysis() {
 104         computeLocalityBindings();
 105         computeTempstoSave();
 106     }
 107
 108     private void computeLocalityBindings() {
 109         LocalityBinding lbmain=new LocalityBinding(typeutil.getMain(), false);
 110         lbmain.setGlobal(0, LOCAL);
 111         lbtovisit.add(lbmain);
 112         discovered.put(lbmain, lbmain);
 113         if (!classtolb.containsKey(lbmain.getMethod().getClassDesc()))
 114             classtolb.put(lbmain.getMethod().getClassDesc(), new HashSet<LocalityBinding>());
 115         classtolb.get(lbmain.getMethod().getClassDesc()).add(lbmain);
 116
 117         if (!methodtolb.containsKey(lbmain.getMethod()))
 118             methodtolb.put(lbmain.getMethod(), new HashSet<LocalityBinding>());
 119         methodtolb.get(lbmain.getMethod()).add(lbmain);
 120
 121         while(!lbtovisit.empty()) {
 122             LocalityBinding lb=(LocalityBinding) lbtovisit.pop();
 123             Integer returnglobal=lb.getGlobalReturn();
 124             MethodDescriptor md=lb.getMethod();
 125             Hashtable<FlatNode,Hashtable<TempDescriptor, Integer>> temptable=new Hashtable<FlatNode,Hashtable<TempDescriptor, Integer>>();
 126             Hashtable<FlatNode, Integer> atomictable=new Hashtable<FlatNode, Integer>();
 127             computeCallsFlags(md, lb, temptable, atomictable);
 128             atomictab.put(lb, atomictable);
 129             temptab.put(lb, temptable);
 130
 131             if (!md.isStatic()&&!returnglobal.equals(lb.getGlobalReturn())) {
 132                 //return type is more precise now
 133                 //rerun everything that call us
 134                 lbtovisit.addAll(dependence.get(lb));
 135             }
 136         }
 137     }
 138
 139
 140     public void computeCallsFlags(MethodDescriptor md, LocalityBinding lb, Hashtable<FlatNode, Hashtable<TempDescriptor, Integer>> temptable, Hashtable<FlatNode, Integer> atomictable) {
 141         FlatMethod fm=state.getMethodFlat(md);
 142         HashSet<FlatNode> tovisit=new HashSet<FlatNode>();
 143         tovisit.add(fm.getNext(0));
 144         {
 145             // Build table for initial node
 146             Hashtable<TempDescriptor,Integer> table=new Hashtable<TempDescriptor,Integer>();
 147             temptable.put(fm, table);
 148             atomictable.put(fm, lb.isAtomic()?1:0);
 149             int offset=md.isStatic()?0:1;
 150             if (!md.isStatic()) {
 151                 table.put(fm.getParameter(0), lb.getGlobalThis());
 152             }
 153             for(int i=offset;i<fm.numParameters();i++) {
 154                 TempDescriptor temp=fm.getParameter(i);
 155                 Integer b=lb.isGlobal(i-offset);
 156                 table.put(temp,b);
 157             }
 158         }
 159
 160         while(!tovisit.isEmpty()) {
 161             FlatNode fn=tovisit.iterator().next();
 162             tovisit.remove(fn);
 163             Hashtable<TempDescriptor, Integer> currtable=new Hashtable<TempDescriptor, Integer>();
 164             int atomicstate=0;
 165             for(int i=0;i<fn.numPrev();i++) {
 166                 FlatNode prevnode=fn.getPrev(i);
 167                 if (atomictable.containsKey(prevnode)) {
 168                     atomicstate=atomictable.get(prevnode).intValue();
 169                 }
 170                 if (!temptable.containsKey(prevnode))
 171                     continue;
 172                 Hashtable<TempDescriptor, Integer> prevtable=temptable.get(prevnode);
 173                 for(Iterator<TempDescriptor> tempit=prevtable.keySet().iterator();tempit.hasNext();) {
 174                     TempDescriptor temp=tempit.next();
 175                     Integer tmpint=prevtable.get(temp);
 176                     Integer oldint=currtable.containsKey(temp)?currtable.get(temp):EITHER;
 177                     Integer newint=merge(tmpint, oldint);
 178                     currtable.put(temp, newint);
 179                 }
 180             }
 181             atomictable.put(fn, atomicstate);
 182             // Process this node
 183             switch(fn.kind()) {
 184             case FKind.FlatAtomicEnterNode:
 185                 processAtomicEnterNode((FlatAtomicEnterNode)fn, atomictable);
 186                 if (!lb.isAtomic())
 187                     lb.setHasAtomic();
 188                 break;
 189             case FKind.FlatAtomicExitNode:
 190                 processAtomicExitNode((FlatAtomicExitNode)fn, atomictable);
 191                 break;
 192             case FKind.FlatCall:
 193                 processCallNode(lb, (FlatCall)fn, currtable, isAtomic(atomictable, fn));
 194                 break;
 195             case FKind.FlatFieldNode:
 196                 processFieldNode(lb, (FlatFieldNode)fn, isAtomic(atomictable, fn), currtable);
 197                 break;
 198             case FKind.FlatSetFieldNode:
 199                 processSetFieldNode(lb, (FlatSetFieldNode)fn, isAtomic(atomictable,fn), currtable);
 200                 break;
 201             case FKind.FlatNew:
 202                 processNew(lb, (FlatNew)fn, isAtomic(atomictable, fn), currtable);
 203                 break;
 204             case FKind.FlatOpNode:
 205                 processOpNode((FlatOpNode)fn, currtable);
 206                 break;
 207             case FKind.FlatCastNode:
 208                 processCastNode((FlatCastNode)fn, currtable);
 209                 break;
 210             case FKind.FlatLiteralNode:
 211                 processLiteralNode((FlatLiteralNode)fn, currtable);
 212                 break;
 213             case FKind.FlatReturnNode:
 214                 processReturnNode(lb, (FlatReturnNode)fn, currtable);
 215                 break;
 216             case FKind.FlatSetElementNode:
 217                 processSetElementNode(lb, (FlatSetElementNode)fn, currtable, isAtomic(atomictable, fn));
 218                 break;
 219             case FKind.FlatElementNode:
 220                 processElementNode(lb, (FlatElementNode)fn, currtable, isAtomic(atomictable, fn));
 221                 break;
 222             case FKind.FlatCondBranch:
 223             case FKind.FlatBackEdge:
 224             case FKind.FlatNop:
 225                 //No action needed for these
 226                 break;
 227             case FKind.FlatFlagActionNode:
 228             case FKind.FlatCheckNode:
 229             case FKind.FlatTagDeclaration:
 230                 throw new Error("Incompatible with tasks!");
 231             case FKind.FlatMethod:
 232             default:
 233                 throw new Error();
 234             }
 235             Hashtable<TempDescriptor,Integer> oldtable=temptable.get(fn);
 236             if (oldtable==null||!oldtable.equals(currtable)) {
 237                 // Update table for this node
 238                 temptable.put(fn, currtable);
 239                 for(int i=0;i<fn.numNext();i++) {
 240                     tovisit.add(fn.getNext(i));
 241                 }
 242             }
 243         }
 244     }
 245
 246     private static boolean isAtomic(Hashtable<FlatNode, Integer> atomictable, FlatNode fn) {
 247         return atomictable.get(fn).intValue()>0;
 248     }
 249
 250     private static Integer merge(Integer a, Integer b) {
 251         if (a==null||a.equals(EITHER))
 252             return b;
 253         if (b==null||b.equals(EITHER))
 254             return a;
 255         if (a.equals(b))
 256             return a;
 257         return CONFLICT;
 258     }
 259
 260     void processCallNode(LocalityBinding currlb, FlatCall fc, Hashtable<TempDescriptor, Integer> currtable, boolean isatomic) {
 261         MethodDescriptor nodemd=fc.getMethod();
 262         Set methodset=fc.getThis()==null?callgraph.getMethods(nodemd):
 263             callgraph.getMethods(nodemd, fc.getThis().getType());
 264         Integer currreturnval=EITHER; //Start off with the either value
 265         for(Iterator methodit=methodset.iterator();methodit.hasNext();) {
 266             MethodDescriptor md=(MethodDescriptor) methodit.next();
 267             boolean isnative=md.getModifiers().isNative();
 268
 269             LocalityBinding lb=new LocalityBinding(md, isatomic);
 270             if (isnative&&isatomic) {
 271                 System.out.println("Don't call native methods in atomic blocks!");
 272             }
 273             for(int i=0;i<fc.numArgs();i++) {
 274                 TempDescriptor arg=fc.getArg(i);
 275                 if(isnative&&(currtable.get(arg).equals(GLOBAL)||
 276                               currtable.get(arg).equals(CONFLICT)))
 277                    throw new Error("Potential call to native method "+md+" with global parameter:\n"+currlb.getExplanation());
 278                 lb.setGlobal(i,currtable.get(arg));
 279             }
 280             if (fc.getThis()!=null) {
 281                 Integer thistype=currtable.get(fc.getThis());
 282                 if (thistype==null)
 283                     thistype=EITHER;
 284                 if(thistype.equals(CONFLICT))
 285                     throw new Error("Using type that can be either local or global in context:\n"+currlb.getExplanation());
 286                 if(thistype.equals(GLOBAL)&&!isatomic)
 287                     throw new Error("Using global object outside of transaction in context:\n"+currlb.getExplanation());
 288                 if (isnative&&thistype.equals(GLOBAL))
 289                     throw new Error("Potential call to native method "+md+" on global objects:\n"+currlb.getExplanation());
 290                 lb.setGlobalThis(thistype);
 291             } else
 292                 lb.setGlobalThis(EITHER);//default value
 293
 294             //lb is built
 295             if (!discovered.containsKey(lb)) {
 296                 if (isnative)
 297                     lb.setGlobalReturn(LOCAL);
 298                 else
 299                     lb.setGlobalReturn(EITHER);
 300                 lb.setParent(currlb);
 301                 lbtovisit.add(lb);
 302                 discovered.put(lb, lb);
 303                 if (!classtolb.containsKey(lb.getMethod().getClassDesc()))
 304                     classtolb.put(lb.getMethod().getClassDesc(), new HashSet<LocalityBinding>());
 305                 classtolb.get(lb.getMethod().getClassDesc()).add(lb);
 306                 if (!methodtolb.containsKey(lb.getMethod()))
 307                     methodtolb.put(lb.getMethod(), new HashSet<LocalityBinding>());
 308                 methodtolb.get(lb.getMethod()).add(lb);
 309             } else
 310                 lb=discovered.get(lb);
 311             Integer returnval=lb.getGlobalReturn();
 312             currreturnval=merge(returnval, currreturnval);
 313             if (!dependence.containsKey(lb))
 314                 dependence.put(lb, new HashSet<LocalityBinding>());
 315             dependence.get(lb).add(currlb);
 316         }
 317         if (fc.getReturnTemp()!=null) {
 318             currtable.put(fc.getReturnTemp(), currreturnval);
 319         }
 320     }
 321
 322     void processFieldNode(LocalityBinding lb, FlatFieldNode ffn, boolean transaction, Hashtable<TempDescriptor, Integer> currtable) {
 323         Integer type=currtable.get(ffn.getSrc());
 324         TempDescriptor dst=ffn.getDst();
 325         if (type.equals(LOCAL)) {
 326             if (ffn.getField().isGlobal())
 327                 currtable.put(dst,GLOBAL);
 328             else
 329                 currtable.put(dst,LOCAL);
 330         } else if (type.equals(GLOBAL)) {
 331             if (!transaction)
 332                 throw new Error("Global access outside of a transaction in context:\n"+lb.getExplanation());
 333             if (ffn.getField().getType().isPrimitive())
 334                 currtable.put(dst, LOCAL); // primitives are local
 335             else
 336                 currtable.put(dst, GLOBAL);
 337         } else if (type.equals(EITHER)) {
 338             if (ffn.getField().getType().isPrimitive())
 339                 currtable.put(dst, LOCAL); // primitives are local
 340             else if (ffn.getField().isGlobal())
 341                 currtable.put(dst, GLOBAL);
 342             else
 343                 currtable.put(dst, EITHER);
 344         } else if (type.equals(CONFLICT)) {
 345             throw new Error("Access to object that could be either global or local in context:\n"+lb.getExplanation());
 346         }
 347     }
 348
 349     //need to handle primitives
 350     void processSetFieldNode(LocalityBinding lb, FlatSetFieldNode fsfn, boolean transaction, Hashtable<TempDescriptor, Integer> currtable) {
 351         Integer srctype=currtable.get(fsfn.getSrc());
 352         Integer dsttype=currtable.get(fsfn.getDst());
 353
 354         if (dsttype.equals(LOCAL)) {
 355             if (fsfn.getField().isGlobal()) {
 356                 if (!(srctype.equals(GLOBAL)||srctype.equals(EITHER)))
 357                     throw new Error("Writing possible local reference to global field in context: \n"+lb.getExplanation());
 358             } else {
 359                 if (!(srctype.equals(LOCAL)||srctype.equals(EITHER)))
 360                     throw new Error("Writing possible global reference to local object in context: \n"+lb.getExplanation());
 361             }
 362         } else if (dsttype.equals(GLOBAL)) {
 363             if (!transaction)
 364                 throw new Error("Global access outside of a transaction in context:\n"+lb.getExplanation());
 365             //okay to store primitives in global object
 366             if (srctype.equals(LOCAL) && fsfn.getField().getType().isPrimitive())
 367                 return;
 368             if (!(srctype.equals(GLOBAL)||srctype.equals(EITHER)))
 369                 throw new Error("Writing possible local reference to global object in context:\n"+lb.getExplanation());
 370         } else if (dsttype.equals(EITHER)) {
 371             if (srctype.equals(CONFLICT))
 372                 throw new Error("Using reference that could be local or global in context:\n"+lb.getExplanation());
 373         } else if (dsttype.equals(CONFLICT)) {
 374             throw new Error("Access to object that could be either global or local in context:\n"+lb.getExplanation());
 375         }
 376     }
 377
 378     void processNew(LocalityBinding lb, FlatNew fn, boolean transaction, Hashtable<TempDescriptor, Integer> currtable) {
 379         if (fn.isGlobal()&&!transaction) {
 380             throw new Error("Allocating global object outside of transaction in context:"+lb.getExplanation());
 381         }
 382         if (fn.isGlobal())
 383             currtable.put(fn.getDst(), GLOBAL);
 384         else
 385             currtable.put(fn.getDst(), LOCAL);
 386     }
 387
 388     void processOpNode(FlatOpNode fon, Hashtable<TempDescriptor, Integer> currtable) {
 389         /* Just propagate value */
 390         currtable.put(fon.getDest(), currtable.get(fon.getLeft()));
 391     }
 392
 393     void processCastNode(FlatCastNode fcn, Hashtable<TempDescriptor, Integer> currtable) {
 394         currtable.put(fcn.getDst(), currtable.get(fcn.getSrc()));
 395     }
 396
 397     void processLiteralNode(FlatLiteralNode fln, Hashtable<TempDescriptor, Integer> currtable) {
 398         //null is either
 399         if (fln.getValue()==null)
 400             currtable.put(fln.getDst(), EITHER);
 401         else
 402             currtable.put(fln.getDst(), LOCAL);
 403     }
 404
 405     void processReturnNode(LocalityBinding lb, FlatReturnNode frn, Hashtable<TempDescriptor, Integer> currtable) {
 406         if(frn.getReturnTemp()!=null) {
 407             Integer returntype=currtable.get(frn.getReturnTemp());
 408             lb.setGlobalReturn(merge(returntype, lb.getGlobalReturn()));
 409         }
 410     }
 411
 412     void processSetElementNode(LocalityBinding lb, FlatSetElementNode fsen, Hashtable<TempDescriptor, Integer> currtable, boolean isatomic) {
 413         Integer srctype=currtable.get(fsen.getSrc());
 414         Integer dsttype=currtable.get(fsen.getDst());
 415
 416         if (dsttype.equals(LOCAL)) {
 417             if (!(srctype.equals(LOCAL)||srctype.equals(EITHER)))
 418                 throw new Error("Writing possible global reference to local object in context:\n"+lb.getExplanation());
 419         } else if (dsttype.equals(GLOBAL)) {
 420             if (!(srctype.equals(GLOBAL)||srctype.equals(EITHER)))
 421                 throw new Error("Writing possible local reference to global object in context:\n"+lb.getExplanation());
 422             if (!isatomic)
 423                 throw new Error("Global access outside of a transaction in context:\n"+lb.getExplanation());
 424         } else if (dsttype.equals(EITHER)) {
 425             if (srctype.equals(CONFLICT))
 426                 throw new Error("Using reference that could be local or global in context:\n"+lb.getExplanation());
 427         } else if (dsttype.equals(CONFLICT)) {
 428             throw new Error("Access to object that could be either global or local in context:\n"+lb.getExplanation());
 429         }
 430     }
 431
 432     void processElementNode(LocalityBinding lb, FlatElementNode fen, Hashtable<TempDescriptor, Integer> currtable, boolean isatomic) {
 433         Integer type=currtable.get(fen.getSrc());
 434         TempDescriptor dst=fen.getDst();
 435         if (type.equals(LOCAL)) {
 436             currtable.put(dst,LOCAL);
 437         } else if (type.equals(GLOBAL)) {
 438             if (!isatomic)
 439                 throw new Error("Global access outside of a transaction in context:\n"+lb.getExplanation());
 440             currtable.put(dst, GLOBAL);
 441         } else if (type.equals(EITHER)) {
 442             currtable.put(dst, EITHER);
 443         } else if (type.equals(CONFLICT)) {
 444             throw new Error("Access to object that could be either global or local in context:\n"+lb.getExplanation());
 445         }
 446     }
 447
 448     void processAtomicEnterNode(FlatAtomicEnterNode fen, Hashtable<FlatNode, Integer> atomictable) {
 449         int atomic=atomictable.get(fen).intValue();
 450         atomictable.put(fen, new Integer(atomic+1));
 451     }
 452
 453     void processAtomicExitNode(FlatAtomicExitNode fen, Hashtable<FlatNode, Integer> atomictable) {
 454         int atomic=atomictable.get(fen).intValue();
 455         atomictable.put(fen, new Integer(atomic-1));
 456     }
 457
 458     private Hashtable<FlatNode, Set<TempDescriptor>> computeLiveTemps(FlatMethod fm) {
 459         Hashtable<FlatNode, Set<TempDescriptor>> nodetotemps=new Hashtable<FlatNode, Set<TempDescriptor>>();
 460
 461         Set<FlatNode> toprocess=fm.getNodeSet();
 462
 463         while(!toprocess.isEmpty()) {
 464             FlatNode fn=toprocess.iterator().next();
 465             toprocess.remove(fn);
 466
 467             List<TempDescriptor> reads=Arrays.asList(fn.readsTemps());
 468             List<TempDescriptor> writes=Arrays.asList(fn.readsTemps());
 469
 470             HashSet<TempDescriptor> tempset=new HashSet<TempDescriptor>();
 471             for(int i=0;i<fn.numNext();i++) {
 472                 FlatNode fnnext=fn.getNext(i);
 473                 if (nodetotemps.containsKey(fnnext))
 474                     tempset.addAll(nodetotemps.get(fnnext));
 475             }
 476             tempset.removeAll(writes);
 477             tempset.addAll(reads);
 478             if (!nodetotemps.containsKey(fn)||
 479                 nodetotemps.get(fn).equals(tempset)) {
 480                 nodetotemps.put(fn, tempset);
 481                 for(int i=0;i<fn.numPrev();i++)
 482                     toprocess.add(fn.getPrev(i));
 483             }
 484         }
 485         return nodetotemps;
 486     }
 487
 488     private void computeTempstoSave() {
 489         for(Iterator<LocalityBinding> lbit=getLocalityBindings().iterator();lbit.hasNext();) {
 490             LocalityBinding lb=lbit.next();
 491             computeTempstoSave(lb);
 492         }
 493     }
 494
 495     /* Need to checkpoint all temps that could be read from along any
 496      * path that are either:
 497        1) Written to by any assignment inside the transaction
 498        2) Read from a global temp.
 499
 500        Generate tempstosave map from
 501        localitybinding->flatatomicenternode->Set<TempDescriptors>
 502     */
 503
 504     private void computeTempstoSave(LocalityBinding lb) {
 505         if (lb.isAtomic())
 506             return;
 507         Hashtable<FlatNode, Integer> atomictab=getAtomic(lb);
 508         Hashtable<FlatNode, Hashtable<TempDescriptor, Integer>> temptab=getNodeTempInfo(lb);
 509         MethodDescriptor md=lb.getMethod();
 510         FlatMethod fm=state.getMethodFlat(md);
 511
 512         Hashtable<FlatNode, Set<TempDescriptor>> nodetotemps=computeLiveTemps(fm);
 513         Hashtable<FlatAtomicEnterNode, Set<TempDescriptor>> nodetosavetemps=new Hashtable<FlatAtomicEnterNode, Set<TempDescriptor>>();
 514         tempstosave.put(lb, nodetosavetemps);
 515
 516         Hashtable<FlatNode, FlatAtomicEnterNode> nodemap=new Hashtable<FlatNode, FlatAtomicEnterNode>();
 517
 518         HashSet<FlatNode> toprocess=new HashSet<FlatNode>();
 519         HashSet<FlatNode> discovered=new HashSet<FlatNode>();
 520         toprocess.add(fm);
 521         discovered.add(fm);
 522         while(!toprocess.isEmpty()) {
 523             FlatNode fn=toprocess.iterator().next();
 524             toprocess.remove(fn);
 525             boolean isatomic=atomictab.get(fn).intValue()>0;
 526             if (isatomic&&
 527                 atomictab.get(fn.getPrev(0)).intValue()==0) {
 528                 assert(fn.getPrev(0).kind()==FKind.FlatAtomicEnterNode);
 529                 nodemap.put(fn, (FlatAtomicEnterNode)fn);
 530                 nodetosavetemps.put((FlatAtomicEnterNode)fn, new HashSet<TempDescriptor>());
 531             } else if (isatomic) {
 532                 FlatAtomicEnterNode atomicnode=nodemap.get(fn);
 533                 Set<TempDescriptor> livetemps=nodetotemps.get(fn);
 534                 List<TempDescriptor> reads=Arrays.asList(fn.readsTemps());
 535                 List<TempDescriptor> writes=Arrays.asList(fn.readsTemps());
 536
 537                 for(Iterator<TempDescriptor> tempit=livetemps.iterator();tempit.hasNext();) {
 538                     TempDescriptor tmp=tempit.next();
 539                     if (writes.contains(tmp)) {
 540                         nodetosavetemps.get(fn).add(tmp);
 541                     } else if (reads.contains(tmp)&&temptab.get(fn).get(tmp)==GLOBAL) {
 542                         nodetosavetemps.get(fn).add(tmp);
 543                     }
 544                 }
 545             }
 546             for(int i=0;i<fn.numNext();i++) {
 547                 FlatNode fnnext=fn.getNext(i);
 548                 if (!discovered.contains(fnnext)) {
 549                     discovered.add(fnnext);
 550                     toprocess.add(fnnext);
 551                     if(isatomic) {
 552                         nodemap.put(fnnext, nodemap.get(fn));
 553                     }
 554                 }
 555             }
 556         }
 557     }
 558 }