1 package Analysis.SSJava;
3 import java.util.ArrayList;
4 import java.util.Collections;
5 import java.util.Comparator;
6 import java.util.HashSet;
7 import java.util.Hashtable;
8 import java.util.Iterator;
11 import java.util.StringTokenizer;
12 import java.util.Vector;
14 import Analysis.SSJava.FlowDownCheck.ComparisonResult;
15 import Analysis.SSJava.FlowDownCheck.CompositeLattice;
16 import IR.AnnotationDescriptor;
17 import IR.ClassDescriptor;
19 import IR.FieldDescriptor;
20 import IR.MethodDescriptor;
21 import IR.NameDescriptor;
24 import IR.SymbolTable;
25 import IR.TypeDescriptor;
26 import IR.VarDescriptor;
27 import IR.Tree.ArrayAccessNode;
28 import IR.Tree.AssignmentNode;
29 import IR.Tree.BlockExpressionNode;
30 import IR.Tree.BlockNode;
31 import IR.Tree.BlockStatementNode;
32 import IR.Tree.CastNode;
33 import IR.Tree.CreateObjectNode;
34 import IR.Tree.DeclarationNode;
35 import IR.Tree.ExpressionNode;
36 import IR.Tree.FieldAccessNode;
37 import IR.Tree.IfStatementNode;
39 import IR.Tree.LiteralNode;
40 import IR.Tree.LoopNode;
41 import IR.Tree.MethodInvokeNode;
42 import IR.Tree.NameNode;
43 import IR.Tree.OpNode;
44 import IR.Tree.ReturnNode;
45 import IR.Tree.SubBlockNode;
46 import IR.Tree.SwitchBlockNode;
47 import IR.Tree.SwitchStatementNode;
48 import IR.Tree.SynchronizedNode;
49 import IR.Tree.TertiaryNode;
50 import IR.Tree.TreeNode;
53 public class FlowDownCheck {
56 static SSJavaAnalysis ssjava;
58 Set<ClassDescriptor> toanalyze;
59 List<ClassDescriptor> toanalyzeList;
61 Set<MethodDescriptor> toanalyzeMethod;
62 List<MethodDescriptor> toanalyzeMethodList;
64 // mapping from 'descriptor' to 'composite location'
65 Hashtable<Descriptor, CompositeLocation> d2loc;
67 Hashtable<MethodDescriptor, CompositeLocation> md2ReturnLoc;
68 Hashtable<MethodDescriptor, ReturnLocGenerator> md2ReturnLocGen;
70 // mapping from 'locID' to 'class descriptor'
71 Hashtable<String, ClassDescriptor> fieldLocName2cd;
73 boolean deterministic = true;
75 public FlowDownCheck(SSJavaAnalysis ssjava, State state) {
79 this.toanalyzeList = new ArrayList<ClassDescriptor>();
81 this.toanalyze = new HashSet<ClassDescriptor>();
84 this.toanalyzeMethodList = new ArrayList<MethodDescriptor>();
86 this.toanalyzeMethod = new HashSet<MethodDescriptor>();
88 this.d2loc = new Hashtable<Descriptor, CompositeLocation>();
89 this.fieldLocName2cd = new Hashtable<String, ClassDescriptor>();
90 this.md2ReturnLoc = new Hashtable<MethodDescriptor, CompositeLocation>();
91 this.md2ReturnLocGen = new Hashtable<MethodDescriptor, ReturnLocGenerator>();
96 // construct mapping from the location name to the class descriptor
97 // assume that the location name is unique through the whole program
99 Set<ClassDescriptor> cdSet = ssjava.getCd2lattice().keySet();
100 for (Iterator iterator = cdSet.iterator(); iterator.hasNext();) {
101 ClassDescriptor cd = (ClassDescriptor) iterator.next();
102 SSJavaLattice<String> lattice = ssjava.getCd2lattice().get(cd);
103 Set<String> fieldLocNameSet = lattice.getKeySet();
105 for (Iterator iterator2 = fieldLocNameSet.iterator(); iterator2.hasNext();) {
106 String fieldLocName = (String) iterator2.next();
107 fieldLocName2cd.put(fieldLocName, cd);
114 public boolean toAnalyzeIsEmpty() {
116 return toanalyzeList.isEmpty();
118 return toanalyze.isEmpty();
122 public ClassDescriptor toAnalyzeNext() {
124 return toanalyzeList.remove(0);
126 ClassDescriptor cd = toanalyze.iterator().next();
127 toanalyze.remove(cd);
132 public void setupToAnalyze() {
133 SymbolTable classtable = state.getClassSymbolTable();
135 toanalyzeList.clear();
136 toanalyzeList.addAll(classtable.getValueSet());
137 Collections.sort(toanalyzeList, new Comparator<ClassDescriptor>() {
138 public int compare(ClassDescriptor o1, ClassDescriptor o2) {
139 return o1.getClassName().compareToIgnoreCase(o2.getClassName());
144 toanalyze.addAll(classtable.getValueSet());
148 public void setupToAnalazeMethod(ClassDescriptor cd) {
150 SymbolTable methodtable = cd.getMethodTable();
152 toanalyzeMethodList.clear();
153 toanalyzeMethodList.addAll(methodtable.getValueSet());
154 Collections.sort(toanalyzeMethodList, new Comparator<MethodDescriptor>() {
155 public int compare(MethodDescriptor o1, MethodDescriptor o2) {
156 return o1.getSymbol().compareToIgnoreCase(o2.getSymbol());
160 toanalyzeMethod.clear();
161 toanalyzeMethod.addAll(methodtable.getValueSet());
165 public boolean toAnalyzeMethodIsEmpty() {
167 return toanalyzeMethodList.isEmpty();
169 return toanalyzeMethod.isEmpty();
173 public MethodDescriptor toAnalyzeMethodNext() {
175 return toanalyzeMethodList.remove(0);
177 MethodDescriptor md = toanalyzeMethod.iterator().next();
178 toanalyzeMethod.remove(md);
183 public void flowDownCheck() {
185 // phase 1 : checking declaration node and creating mapping of 'type
186 // desciptor' & 'location'
189 while (!toAnalyzeIsEmpty()) {
190 ClassDescriptor cd = toAnalyzeNext();
192 if (ssjava.needToBeAnnoated(cd)) {
194 ClassDescriptor superDesc = cd.getSuperDesc();
196 if (superDesc != null && (!superDesc.getSymbol().equals("Object"))) {
197 checkOrderingInheritance(superDesc, cd);
200 checkDeclarationInClass(cd);
202 setupToAnalazeMethod(cd);
203 while (!toAnalyzeMethodIsEmpty()) {
204 MethodDescriptor md = toAnalyzeMethodNext();
205 if (ssjava.needTobeAnnotated(md)) {
206 checkDeclarationInMethodBody(cd, md);
214 // phase2 : checking assignments
217 while (!toAnalyzeIsEmpty()) {
218 ClassDescriptor cd = toAnalyzeNext();
220 setupToAnalazeMethod(cd);
221 while (!toAnalyzeMethodIsEmpty()) {
222 MethodDescriptor md = toAnalyzeMethodNext();
223 if (ssjava.needTobeAnnotated(md)) {
224 System.out.println("SSJAVA: Checking assignments: " + md);
225 checkMethodBody(cd, md, null);
232 private void checkOrderingInheritance(ClassDescriptor superCd, ClassDescriptor cd) {
233 // here, we're going to check that sub class keeps same relative orderings
234 // in respect to super class
236 SSJavaLattice<String> superLattice = ssjava.getClassLattice(superCd);
237 SSJavaLattice<String> subLattice = ssjava.getClassLattice(cd);
239 if (superLattice != null) {
240 // if super class doesn't define lattice, then we don't need to check its
242 if (subLattice == null) {
243 throw new Error("If a parent class '" + superCd
244 + "' has a ordering lattice, its subclass '" + cd + "' should have one.");
247 Set<Pair<String, String>> superPairSet = superLattice.getOrderingPairSet();
248 Set<Pair<String, String>> subPairSet = subLattice.getOrderingPairSet();
250 for (Iterator iterator = superPairSet.iterator(); iterator.hasNext();) {
251 Pair<String, String> pair = (Pair<String, String>) iterator.next();
253 if (!subPairSet.contains(pair)) {
254 throw new Error("Subclass '" + cd + "' does not have the relative ordering '"
255 + pair.getSecond() + " < " + pair.getFirst()
256 + "' that is defined by its superclass '" + superCd + "'.");
261 MethodLattice<String> superMethodDefaultLattice = ssjava.getMethodDefaultLattice(superCd);
262 MethodLattice<String> subMethodDefaultLattice = ssjava.getMethodDefaultLattice(cd);
264 if (superMethodDefaultLattice != null) {
265 if (subMethodDefaultLattice == null) {
266 throw new Error("When a parent class '" + superCd
267 + "' defines a default method lattice, its subclass '" + cd + "' should define one.");
270 Set<Pair<String, String>> superPairSet = superMethodDefaultLattice.getOrderingPairSet();
271 Set<Pair<String, String>> subPairSet = subMethodDefaultLattice.getOrderingPairSet();
273 for (Iterator iterator = superPairSet.iterator(); iterator.hasNext();) {
274 Pair<String, String> pair = (Pair<String, String>) iterator.next();
276 if (!subPairSet.contains(pair)) {
277 throw new Error("Subclass '" + cd + "' does not have the relative ordering '"
278 + pair.getSecond() + " < " + pair.getFirst()
279 + "' that is defined by its superclass '" + superCd
280 + "' in the method default lattice.");
288 public Hashtable getMap() {
292 private void checkDeclarationInMethodBody(ClassDescriptor cd, MethodDescriptor md) {
293 BlockNode bn = state.getMethodBody(md);
296 // first, check annotations on method parameters
297 List<CompositeLocation> paramList = new ArrayList<CompositeLocation>();
298 for (int i = 0; i < md.numParameters(); i++) {
299 // process annotations on method parameters
300 VarDescriptor vd = (VarDescriptor) md.getParameter(i);
301 assignLocationOfVarDescriptor(vd, md, md.getParameterTable(), null);
302 paramList.add(d2loc.get(vd));
304 Vector<AnnotationDescriptor> methodAnnotations = md.getModifiers().getAnnotations();
306 // second, check return location annotation
307 if (!md.getReturnType().isVoid()) {
308 CompositeLocation returnLocComp = null;
310 boolean hasReturnLocDeclaration = false;
311 if (methodAnnotations != null) {
312 for (int i = 0; i < methodAnnotations.size(); i++) {
313 AnnotationDescriptor an = methodAnnotations.elementAt(i);
314 if (an.getMarker().equals(ssjava.RETURNLOC)) {
315 // this case, developer explicitly defines method lattice
316 String returnLocDeclaration = an.getValue();
317 returnLocComp = parseLocationDeclaration(md, null, returnLocDeclaration);
318 hasReturnLocDeclaration = true;
323 if (!hasReturnLocDeclaration) {
324 // if developer does not define method lattice
325 // search return location in the method default lattice
326 String rtrStr = ssjava.getMethodLattice(md).getReturnLoc();
327 if (rtrStr != null) {
328 returnLocComp = new CompositeLocation(new Location(md, rtrStr));
332 if (returnLocComp == null) {
333 throw new Error("Return location is not specified for the method " + md + " at "
334 + cd.getSourceFileName());
337 md2ReturnLoc.put(md, returnLocComp);
339 // check this location
340 MethodLattice<String> methodLattice = ssjava.getMethodLattice(md);
341 String thisLocId = methodLattice.getThisLoc();
342 if (thisLocId == null) {
343 throw new Error("Method '" + md + "' does not have the definition of 'this' location at "
344 + md.getClassDesc().getSourceFileName());
346 CompositeLocation thisLoc = new CompositeLocation(new Location(md, thisLocId));
347 paramList.add(0, thisLoc);
349 // System.out.println("### ReturnLocGenerator=" + md);
350 // System.out.println("### md2ReturnLoc.get(md)=" + md2ReturnLoc.get(md));
352 md2ReturnLocGen.put(md, new ReturnLocGenerator(md2ReturnLoc.get(md), md, paramList, md
353 + " of " + cd.getSourceFileName()));
356 // fourth, check declarations inside of method
358 checkDeclarationInBlockNode(md, md.getParameterTable(), bn);
362 private void checkDeclarationInBlockNode(MethodDescriptor md, SymbolTable nametable, BlockNode bn) {
363 bn.getVarTable().setParent(nametable);
364 for (int i = 0; i < bn.size(); i++) {
365 BlockStatementNode bsn = bn.get(i);
366 checkDeclarationInBlockStatementNode(md, bn.getVarTable(), bsn);
370 private void checkDeclarationInBlockStatementNode(MethodDescriptor md, SymbolTable nametable,
371 BlockStatementNode bsn) {
373 switch (bsn.kind()) {
374 case Kind.SubBlockNode:
375 checkDeclarationInSubBlockNode(md, nametable, (SubBlockNode) bsn);
378 case Kind.DeclarationNode:
379 checkDeclarationNode(md, nametable, (DeclarationNode) bsn);
383 checkDeclarationInLoopNode(md, nametable, (LoopNode) bsn);
386 case Kind.IfStatementNode:
387 checkDeclarationInIfStatementNode(md, nametable, (IfStatementNode) bsn);
390 case Kind.SwitchStatementNode:
391 checkDeclarationInSwitchStatementNode(md, nametable, (SwitchStatementNode) bsn);
394 case Kind.SynchronizedNode:
395 checkDeclarationInSynchronizedNode(md, nametable, (SynchronizedNode) bsn);
401 private void checkDeclarationInSynchronizedNode(MethodDescriptor md, SymbolTable nametable,
402 SynchronizedNode sbn) {
403 checkDeclarationInBlockNode(md, nametable, sbn.getBlockNode());
406 private void checkDeclarationInSwitchStatementNode(MethodDescriptor md, SymbolTable nametable,
407 SwitchStatementNode ssn) {
408 BlockNode sbn = ssn.getSwitchBody();
409 for (int i = 0; i < sbn.size(); i++) {
410 SwitchBlockNode node = (SwitchBlockNode) sbn.get(i);
411 checkDeclarationInBlockNode(md, nametable, node.getSwitchBlockStatement());
415 private void checkDeclarationInIfStatementNode(MethodDescriptor md, SymbolTable nametable,
416 IfStatementNode isn) {
417 checkDeclarationInBlockNode(md, nametable, isn.getTrueBlock());
418 if (isn.getFalseBlock() != null)
419 checkDeclarationInBlockNode(md, nametable, isn.getFalseBlock());
422 private void checkDeclarationInLoopNode(MethodDescriptor md, SymbolTable nametable, LoopNode ln) {
424 if (ln.getType() == LoopNode.FORLOOP) {
425 // check for loop case
426 ClassDescriptor cd = md.getClassDesc();
427 BlockNode bn = ln.getInitializer();
428 for (int i = 0; i < bn.size(); i++) {
429 BlockStatementNode bsn = bn.get(i);
430 checkDeclarationInBlockStatementNode(md, nametable, bsn);
435 checkDeclarationInBlockNode(md, nametable, ln.getBody());
438 private void checkMethodBody(ClassDescriptor cd, MethodDescriptor md,
439 CompositeLocation constraints) {
440 BlockNode bn = state.getMethodBody(md);
441 checkLocationFromBlockNode(md, md.getParameterTable(), bn, constraints);
444 private String generateErrorMessage(ClassDescriptor cd, TreeNode tn) {
446 return cd.getSourceFileName() + "::" + tn.getNumLine();
448 return cd.getSourceFileName();
453 private CompositeLocation checkLocationFromBlockNode(MethodDescriptor md, SymbolTable nametable,
454 BlockNode bn, CompositeLocation constraint) {
456 bn.getVarTable().setParent(nametable);
457 for (int i = 0; i < bn.size(); i++) {
458 BlockStatementNode bsn = bn.get(i);
459 checkLocationFromBlockStatementNode(md, bn.getVarTable(), bsn, constraint);
461 return new CompositeLocation();
465 private CompositeLocation checkLocationFromBlockStatementNode(MethodDescriptor md,
466 SymbolTable nametable, BlockStatementNode bsn, CompositeLocation constraint) {
468 CompositeLocation compLoc = null;
469 switch (bsn.kind()) {
470 case Kind.BlockExpressionNode:
472 checkLocationFromBlockExpressionNode(md, nametable, (BlockExpressionNode) bsn, constraint);
475 case Kind.DeclarationNode:
476 compLoc = checkLocationFromDeclarationNode(md, nametable, (DeclarationNode) bsn, constraint);
479 case Kind.IfStatementNode:
480 compLoc = checkLocationFromIfStatementNode(md, nametable, (IfStatementNode) bsn, constraint);
484 compLoc = checkLocationFromLoopNode(md, nametable, (LoopNode) bsn, constraint);
487 case Kind.ReturnNode:
488 compLoc = checkLocationFromReturnNode(md, nametable, (ReturnNode) bsn, constraint);
491 case Kind.SubBlockNode:
492 compLoc = checkLocationFromSubBlockNode(md, nametable, (SubBlockNode) bsn, constraint);
495 case Kind.ContinueBreakNode:
496 compLoc = new CompositeLocation();
499 case Kind.SwitchStatementNode:
501 checkLocationFromSwitchStatementNode(md, nametable, (SwitchStatementNode) bsn, constraint);
507 private CompositeLocation checkLocationFromSwitchStatementNode(MethodDescriptor md,
508 SymbolTable nametable, SwitchStatementNode ssn, CompositeLocation constraint) {
510 ClassDescriptor cd = md.getClassDesc();
511 CompositeLocation condLoc =
512 checkLocationFromExpressionNode(md, nametable, ssn.getCondition(), new CompositeLocation(),
514 BlockNode sbn = ssn.getSwitchBody();
516 constraint = generateNewConstraint(constraint, condLoc);
518 for (int i = 0; i < sbn.size(); i++) {
519 checkLocationFromSwitchBlockNode(md, nametable, (SwitchBlockNode) sbn.get(i), constraint);
521 return new CompositeLocation();
524 private CompositeLocation checkLocationFromSwitchBlockNode(MethodDescriptor md,
525 SymbolTable nametable, SwitchBlockNode sbn, CompositeLocation constraint) {
527 CompositeLocation blockLoc =
528 checkLocationFromBlockNode(md, nametable, sbn.getSwitchBlockStatement(), constraint);
534 private CompositeLocation checkLocationFromReturnNode(MethodDescriptor md, SymbolTable nametable,
535 ReturnNode rn, CompositeLocation constraint) {
537 ExpressionNode returnExp = rn.getReturnExpression();
539 CompositeLocation returnValueLoc;
540 if (returnExp != null) {
542 checkLocationFromExpressionNode(md, nametable, returnExp, new CompositeLocation(),
545 // if this return statement is inside branch, return value has an implicit
546 // flow from conditional location
547 if (constraint != null) {
548 Set<CompositeLocation> inputGLB = new HashSet<CompositeLocation>();
549 inputGLB.add(returnValueLoc);
550 inputGLB.add(constraint);
552 CompositeLattice.calculateGLB(inputGLB, generateErrorMessage(md.getClassDesc(), rn));
555 // check if return value is equal or higher than RETRUNLOC of method
556 // declaration annotation
557 CompositeLocation declaredReturnLoc = md2ReturnLoc.get(md);
560 CompositeLattice.compare(returnValueLoc, declaredReturnLoc, false,
561 generateErrorMessage(md.getClassDesc(), rn));
563 if (compareResult == ComparisonResult.LESS || compareResult == ComparisonResult.INCOMPARABLE) {
565 "Return value location is not equal or higher than the declaraed return location at "
566 + md.getClassDesc().getSourceFileName() + "::" + rn.getNumLine());
570 return new CompositeLocation();
573 private boolean hasOnlyLiteralValue(ExpressionNode en) {
574 if (en.kind() == Kind.LiteralNode) {
581 private CompositeLocation checkLocationFromLoopNode(MethodDescriptor md, SymbolTable nametable,
582 LoopNode ln, CompositeLocation constraint) {
584 ClassDescriptor cd = md.getClassDesc();
585 if (ln.getType() == LoopNode.WHILELOOP || ln.getType() == LoopNode.DOWHILELOOP) {
587 CompositeLocation condLoc =
588 checkLocationFromExpressionNode(md, nametable, ln.getCondition(),
589 new CompositeLocation(), constraint, false);
590 // addLocationType(ln.getCondition().getType(), (condLoc));
592 constraint = generateNewConstraint(constraint, condLoc);
593 checkLocationFromBlockNode(md, nametable, ln.getBody(), constraint);
595 return new CompositeLocation();
598 // check 'for loop' case
599 BlockNode bn = ln.getInitializer();
600 bn.getVarTable().setParent(nametable);
602 // calculate glb location of condition and update statements
603 CompositeLocation condLoc =
604 checkLocationFromExpressionNode(md, bn.getVarTable(), ln.getCondition(),
605 new CompositeLocation(), constraint, false);
606 // addLocationType(ln.getCondition().getType(), condLoc);
608 constraint = generateNewConstraint(constraint, condLoc);
610 checkLocationFromBlockNode(md, bn.getVarTable(), ln.getUpdate(), constraint);
611 checkLocationFromBlockNode(md, bn.getVarTable(), ln.getBody(), constraint);
613 return new CompositeLocation();
619 private CompositeLocation checkLocationFromSubBlockNode(MethodDescriptor md,
620 SymbolTable nametable, SubBlockNode sbn, CompositeLocation constraint) {
621 CompositeLocation compLoc =
622 checkLocationFromBlockNode(md, nametable, sbn.getBlockNode(), constraint);
626 private CompositeLocation generateNewConstraint(CompositeLocation currentCon,
627 CompositeLocation newCon) {
629 if (currentCon == null) {
632 // compute GLB of current constraint and new constraint
633 Set<CompositeLocation> inputSet = new HashSet<CompositeLocation>();
634 inputSet.add(currentCon);
635 inputSet.add(newCon);
636 return CompositeLattice.calculateGLB(inputSet, "");
641 private CompositeLocation checkLocationFromIfStatementNode(MethodDescriptor md,
642 SymbolTable nametable, IfStatementNode isn, CompositeLocation constraint) {
644 CompositeLocation condLoc =
645 checkLocationFromExpressionNode(md, nametable, isn.getCondition(), new CompositeLocation(),
648 // addLocationType(isn.getCondition().getType(), condLoc);
650 constraint = generateNewConstraint(constraint, condLoc);
651 checkLocationFromBlockNode(md, nametable, isn.getTrueBlock(), constraint);
653 if (isn.getFalseBlock() != null) {
654 checkLocationFromBlockNode(md, nametable, isn.getFalseBlock(), constraint);
657 return new CompositeLocation();
660 private CompositeLocation checkLocationFromDeclarationNode(MethodDescriptor md,
661 SymbolTable nametable, DeclarationNode dn, CompositeLocation constraint) {
663 VarDescriptor vd = dn.getVarDescriptor();
665 CompositeLocation destLoc = d2loc.get(vd);
667 if (dn.getExpression() != null) {
668 CompositeLocation expressionLoc =
669 checkLocationFromExpressionNode(md, nametable, dn.getExpression(),
670 new CompositeLocation(), constraint, false);
671 // addTypeLocation(dn.getExpression().getType(), expressionLoc);
673 if (expressionLoc != null) {
674 // checking location order
675 if (!CompositeLattice.isGreaterThan(expressionLoc, destLoc,
676 generateErrorMessage(md.getClassDesc(), dn))) {
677 throw new Error("The value flow from " + expressionLoc + " to " + destLoc
678 + " does not respect location hierarchy on the assignment " + dn.printNode(0)
679 + " at " + md.getClassDesc().getSourceFileName() + "::" + dn.getNumLine());
682 return expressionLoc;
686 return new CompositeLocation();
692 private void checkDeclarationInSubBlockNode(MethodDescriptor md, SymbolTable nametable,
694 checkDeclarationInBlockNode(md, nametable.getParent(), sbn.getBlockNode());
697 private CompositeLocation checkLocationFromBlockExpressionNode(MethodDescriptor md,
698 SymbolTable nametable, BlockExpressionNode ben, CompositeLocation constraint) {
699 CompositeLocation compLoc =
700 checkLocationFromExpressionNode(md, nametable, ben.getExpression(), null, constraint, false);
701 // addTypeLocation(ben.getExpression().getType(), compLoc);
705 private CompositeLocation checkLocationFromExpressionNode(MethodDescriptor md,
706 SymbolTable nametable, ExpressionNode en, CompositeLocation loc,
707 CompositeLocation constraint, boolean isLHS) {
709 CompositeLocation compLoc = null;
712 case Kind.AssignmentNode:
714 checkLocationFromAssignmentNode(md, nametable, (AssignmentNode) en, loc, constraint);
717 case Kind.FieldAccessNode:
719 checkLocationFromFieldAccessNode(md, nametable, (FieldAccessNode) en, loc, constraint);
723 compLoc = checkLocationFromNameNode(md, nametable, (NameNode) en, loc, constraint);
727 compLoc = checkLocationFromOpNode(md, nametable, (OpNode) en, constraint);
730 case Kind.CreateObjectNode:
731 compLoc = checkLocationFromCreateObjectNode(md, nametable, (CreateObjectNode) en);
734 case Kind.ArrayAccessNode:
736 checkLocationFromArrayAccessNode(md, nametable, (ArrayAccessNode) en, constraint, isLHS);
739 case Kind.LiteralNode:
740 compLoc = checkLocationFromLiteralNode(md, nametable, (LiteralNode) en, loc);
743 case Kind.MethodInvokeNode:
745 checkLocationFromMethodInvokeNode(md, nametable, (MethodInvokeNode) en, loc, constraint);
748 case Kind.TertiaryNode:
749 compLoc = checkLocationFromTertiaryNode(md, nametable, (TertiaryNode) en, constraint);
753 compLoc = checkLocationFromCastNode(md, nametable, (CastNode) en, constraint);
756 // case Kind.InstanceOfNode:
757 // checkInstanceOfNode(md, nametable, (InstanceOfNode) en, td);
760 // case Kind.ArrayInitializerNode:
761 // checkArrayInitializerNode(md, nametable, (ArrayInitializerNode) en,
765 // case Kind.ClassTypeNode:
766 // checkClassTypeNode(md, nametable, (ClassTypeNode) en, td);
769 // case Kind.OffsetNode:
770 // checkOffsetNode(md, nametable, (OffsetNode)en, td);
777 // addTypeLocation(en.getType(), compLoc);
782 private CompositeLocation checkLocationFromCastNode(MethodDescriptor md, SymbolTable nametable,
783 CastNode cn, CompositeLocation constraint) {
785 ExpressionNode en = cn.getExpression();
786 return checkLocationFromExpressionNode(md, nametable, en, new CompositeLocation(), constraint,
791 private CompositeLocation checkLocationFromTertiaryNode(MethodDescriptor md,
792 SymbolTable nametable, TertiaryNode tn, CompositeLocation constraint) {
793 ClassDescriptor cd = md.getClassDesc();
795 CompositeLocation condLoc =
796 checkLocationFromExpressionNode(md, nametable, tn.getCond(), new CompositeLocation(),
798 // addLocationType(tn.getCond().getType(), condLoc);
799 CompositeLocation trueLoc =
800 checkLocationFromExpressionNode(md, nametable, tn.getTrueExpr(), new CompositeLocation(),
802 // addLocationType(tn.getTrueExpr().getType(), trueLoc);
803 CompositeLocation falseLoc =
804 checkLocationFromExpressionNode(md, nametable, tn.getFalseExpr(), new CompositeLocation(),
806 // addLocationType(tn.getFalseExpr().getType(), falseLoc);
808 // locations from true/false branches can be TOP when there are only literal
810 // in this case, we don't need to check flow down rule!
812 // check if condLoc is higher than trueLoc & falseLoc
813 if (!trueLoc.get(0).isTop()
814 && !CompositeLattice.isGreaterThan(condLoc, trueLoc, generateErrorMessage(cd, tn))) {
816 "The location of the condition expression is lower than the true expression at "
817 + cd.getSourceFileName() + ":" + tn.getCond().getNumLine());
820 if (!falseLoc.get(0).isTop()
821 && !CompositeLattice.isGreaterThan(condLoc, falseLoc,
822 generateErrorMessage(cd, tn.getCond()))) {
824 "The location of the condition expression is lower than the false expression at "
825 + cd.getSourceFileName() + ":" + tn.getCond().getNumLine());
828 // then, return glb of trueLoc & falseLoc
829 Set<CompositeLocation> glbInputSet = new HashSet<CompositeLocation>();
830 glbInputSet.add(trueLoc);
831 glbInputSet.add(falseLoc);
833 if (glbInputSet.size() == 1) {
836 return CompositeLattice.calculateGLB(glbInputSet, generateErrorMessage(cd, tn));
841 private CompositeLocation checkLocationFromMethodInvokeNode(MethodDescriptor md,
842 SymbolTable nametable, MethodInvokeNode min, CompositeLocation loc,
843 CompositeLocation constraint) {
845 ClassDescriptor cd = md.getClassDesc();
846 MethodDescriptor calleeMD = min.getMethod();
848 NameDescriptor baseName = min.getBaseName();
849 boolean isSystemout = false;
850 if (baseName != null) {
851 isSystemout = baseName.getSymbol().equals("System.out");
854 if (!ssjava.isSSJavaUtil(calleeMD.getClassDesc()) && !ssjava.isTrustMethod(calleeMD)
855 && !calleeMD.getModifiers().isNative() && !isSystemout) {
857 CompositeLocation baseLocation = null;
858 if (min.getExpression() != null) {
860 checkLocationFromExpressionNode(md, nametable, min.getExpression(),
861 new CompositeLocation(), constraint, false);
863 if (min.getMethod().isStatic()) {
864 String globalLocId = ssjava.getMethodLattice(md).getGlobalLoc();
865 if (globalLocId == null) {
866 throw new Error("Method lattice does not define global variable location at "
867 + generateErrorMessage(md.getClassDesc(), min));
869 baseLocation = new CompositeLocation(new Location(md, globalLocId));
871 String thisLocId = ssjava.getMethodLattice(md).getThisLoc();
872 baseLocation = new CompositeLocation(new Location(md, thisLocId));
877 // System.out.println("\n#checkLocationFromMethodInvokeNode=" + min.printNode(0)
878 // + " baseLocation=" + baseLocation + " constraint=" + constraint);
880 if (constraint != null) {
882 CompositeLattice.compare(constraint, baseLocation, true, generateErrorMessage(cd, min));
884 if (compareResult == ComparisonResult.LESS) {
885 throw new Error("Method invocation does not respect the current branch constraint at "
886 + generateErrorMessage(cd, min));
887 } else if (compareResult != ComparisonResult.GREATER) {
888 // if the current constraint is higher than method's THIS location
889 // no need to check constraints!
890 CompositeLocation calleeConstraint =
891 translateCallerLocToCalleeLoc(calleeMD, baseLocation, constraint);
892 // System.out.println("check method body for constraint:" + calleeMD + " calleeConstraint="
893 // + calleeConstraint);
894 checkMethodBody(calleeMD.getClassDesc(), calleeMD, calleeConstraint);
898 checkCalleeConstraints(md, nametable, min, baseLocation, constraint);
900 // checkCallerArgumentLocationConstraints(md, nametable, min,
901 // baseLocation, constraint);
903 if (!min.getMethod().getReturnType().isVoid()) {
904 // If method has a return value, compute the highest possible return
905 // location in the caller's perspective
906 CompositeLocation ceilingLoc =
907 computeCeilingLocationForCaller(md, nametable, min, baseLocation, constraint);
912 return new CompositeLocation(Location.createTopLocation(md));
916 private CompositeLocation translateCallerLocToCalleeLoc(MethodDescriptor calleeMD,
917 CompositeLocation calleeBaseLoc, CompositeLocation constraint) {
919 CompositeLocation calleeConstraint = new CompositeLocation();
921 // if (constraint.startsWith(calleeBaseLoc)) {
922 // if the first part of constraint loc is matched with callee base loc
923 Location thisLoc = new Location(calleeMD, ssjava.getMethodLattice(calleeMD).getThisLoc());
924 calleeConstraint.addLocation(thisLoc);
925 for (int i = calleeBaseLoc.getSize(); i < constraint.getSize(); i++) {
926 calleeConstraint.addLocation(constraint.get(i));
931 return calleeConstraint;
934 private void checkCallerArgumentLocationConstraints(MethodDescriptor md, SymbolTable nametable,
935 MethodInvokeNode min, CompositeLocation callerBaseLoc, CompositeLocation constraint) {
936 // if parameter location consists of THIS and FIELD location,
937 // caller should pass an argument that is comparable to the declared
938 // parameter location
939 // and is not lower than the declared parameter location in the field
942 MethodDescriptor calleemd = min.getMethod();
944 List<CompositeLocation> callerArgList = new ArrayList<CompositeLocation>();
945 List<CompositeLocation> calleeParamList = new ArrayList<CompositeLocation>();
947 MethodLattice<String> calleeLattice = ssjava.getMethodLattice(calleemd);
948 Location calleeThisLoc = new Location(calleemd, calleeLattice.getThisLoc());
950 for (int i = 0; i < min.numArgs(); i++) {
951 ExpressionNode en = min.getArg(i);
952 CompositeLocation callerArgLoc =
953 checkLocationFromExpressionNode(md, nametable, en, new CompositeLocation(), constraint,
955 callerArgList.add(callerArgLoc);
958 // setup callee params set
959 for (int i = 0; i < calleemd.numParameters(); i++) {
960 VarDescriptor calleevd = (VarDescriptor) calleemd.getParameter(i);
961 CompositeLocation calleeLoc = d2loc.get(calleevd);
962 calleeParamList.add(calleeLoc);
965 String errorMsg = generateErrorMessage(md.getClassDesc(), min);
967 // System.out.println("checkCallerArgumentLocationConstraints=" + min.printNode(0));
968 // System.out.println("base location=" + callerBaseLoc + " constraint=" + constraint);
970 for (int i = 0; i < calleeParamList.size(); i++) {
971 CompositeLocation calleeParamLoc = calleeParamList.get(i);
972 if (calleeParamLoc.get(0).equals(calleeThisLoc) && calleeParamLoc.getSize() > 1) {
974 // callee parameter location has field information
975 CompositeLocation callerArgLoc = callerArgList.get(i);
977 CompositeLocation paramLocation =
978 translateCalleeParamLocToCaller(md, calleeParamLoc, callerBaseLoc, errorMsg);
980 Set<CompositeLocation> inputGLBSet = new HashSet<CompositeLocation>();
981 if (constraint != null) {
982 inputGLBSet.add(callerArgLoc);
983 inputGLBSet.add(constraint);
985 CompositeLattice.calculateGLB(inputGLBSet,
986 generateErrorMessage(md.getClassDesc(), min));
989 if (!CompositeLattice.isGreaterThan(callerArgLoc, paramLocation, errorMsg)) {
990 throw new Error("Caller argument '" + min.getArg(i).printNode(0) + " : " + callerArgLoc
991 + "' should be higher than corresponding callee's parameter : " + paramLocation
992 + " at " + errorMsg);
1000 private CompositeLocation translateCalleeParamLocToCaller(MethodDescriptor md,
1001 CompositeLocation calleeParamLoc, CompositeLocation callerBaseLocation, String errorMsg) {
1003 CompositeLocation translate = new CompositeLocation();
1005 for (int i = 0; i < callerBaseLocation.getSize(); i++) {
1006 translate.addLocation(callerBaseLocation.get(i));
1009 for (int i = 1; i < calleeParamLoc.getSize(); i++) {
1010 translate.addLocation(calleeParamLoc.get(i));
1013 // System.out.println("TRANSLATED=" + translate + " from calleeParamLoc=" + calleeParamLoc);
1018 private CompositeLocation computeCeilingLocationForCaller(MethodDescriptor md,
1019 SymbolTable nametable, MethodInvokeNode min, CompositeLocation baseLocation,
1020 CompositeLocation constraint) {
1021 List<CompositeLocation> argList = new ArrayList<CompositeLocation>();
1023 // by default, method has a THIS parameter
1024 argList.add(baseLocation);
1026 for (int i = 0; i < min.numArgs(); i++) {
1027 ExpressionNode en = min.getArg(i);
1028 CompositeLocation callerArg =
1029 checkLocationFromExpressionNode(md, nametable, en, new CompositeLocation(), constraint,
1031 argList.add(callerArg);
1034 // System.out.println("\n## computeReturnLocation=" + min.getMethod() + " argList=" + argList);
1035 CompositeLocation ceilLoc = md2ReturnLocGen.get(min.getMethod()).computeReturnLocation(argList);
1036 // System.out.println("## ReturnLocation=" + ceilLoc);
1042 private void checkCalleeConstraints(MethodDescriptor md, SymbolTable nametable,
1043 MethodInvokeNode min, CompositeLocation callerBaseLoc, CompositeLocation constraint) {
1045 // System.out.println("checkCalleeConstraints=" + min.printNode(0));
1047 MethodDescriptor calleemd = min.getMethod();
1049 MethodLattice<String> calleeLattice = ssjava.getMethodLattice(calleemd);
1050 CompositeLocation calleeThisLoc =
1051 new CompositeLocation(new Location(calleemd, calleeLattice.getThisLoc()));
1053 List<CompositeLocation> callerArgList = new ArrayList<CompositeLocation>();
1054 List<CompositeLocation> calleeParamList = new ArrayList<CompositeLocation>();
1056 if (min.numArgs() > 0) {
1057 // caller needs to guarantee that it passes arguments in regarding to
1058 // callee's hierarchy
1060 // setup caller args set
1061 // first, add caller's base(this) location
1062 callerArgList.add(callerBaseLoc);
1063 // second, add caller's arguments
1064 for (int i = 0; i < min.numArgs(); i++) {
1065 ExpressionNode en = min.getArg(i);
1066 CompositeLocation callerArgLoc =
1067 checkLocationFromExpressionNode(md, nametable, en, new CompositeLocation(), constraint,
1069 callerArgList.add(callerArgLoc);
1072 // setup callee params set
1073 // first, add callee's this location
1074 calleeParamList.add(calleeThisLoc);
1075 // second, add callee's parameters
1076 for (int i = 0; i < calleemd.numParameters(); i++) {
1077 VarDescriptor calleevd = (VarDescriptor) calleemd.getParameter(i);
1078 CompositeLocation calleeLoc = d2loc.get(calleevd);
1079 // System.out.println("calleevd=" + calleevd + " loc=" + calleeLoc);
1080 calleeParamList.add(calleeLoc);
1083 // here, check if ordering relations among caller's args respect
1084 // ordering relations in-between callee's args
1085 CHECK: for (int i = 0; i < calleeParamList.size(); i++) {
1086 CompositeLocation calleeLoc1 = calleeParamList.get(i);
1087 CompositeLocation callerLoc1 = callerArgList.get(i);
1089 for (int j = 0; j < calleeParamList.size(); j++) {
1091 CompositeLocation calleeLoc2 = calleeParamList.get(j);
1092 CompositeLocation callerLoc2 = callerArgList.get(j);
1094 if (callerLoc1.get(callerLoc1.getSize() - 1).isTop()
1095 || callerLoc2.get(callerLoc2.getSize() - 1).isTop()) {
1099 // System.out.println("calleeLoc1=" + calleeLoc1);
1100 // System.out.println("calleeLoc2=" + calleeLoc2 + "calleeParamList=" + calleeParamList);
1103 CompositeLattice.compare(callerLoc1, callerLoc2, true,
1104 generateErrorMessage(md.getClassDesc(), min));
1106 CompositeLattice.compare(calleeLoc1, calleeLoc2, true,
1107 generateErrorMessage(md.getClassDesc(), min));
1109 if (calleeResult == ComparisonResult.GREATER
1110 && callerResult != ComparisonResult.GREATER) {
1111 // If calleeLoc1 is higher than calleeLoc2
1112 // then, caller should have same ordering relation in-bet
1113 // callerLoc1 & callerLoc2
1115 String paramName1, paramName2;
1118 paramName1 = "'THIS'";
1120 paramName1 = "'parameter " + calleemd.getParamName(i - 1) + "'";
1124 paramName2 = "'THIS'";
1126 paramName2 = "'parameter " + calleemd.getParamName(j - 1) + "'";
1130 "Caller doesn't respect an ordering relation among method arguments: callee expects that "
1131 + paramName1 + " should be higher than " + paramName2 + " in " + calleemd
1132 + " at " + md.getClassDesc().getSourceFileName() + ":" + min.getNumLine());
1143 private CompositeLocation checkLocationFromArrayAccessNode(MethodDescriptor md,
1144 SymbolTable nametable, ArrayAccessNode aan, CompositeLocation constraint, boolean isLHS) {
1146 ClassDescriptor cd = md.getClassDesc();
1148 CompositeLocation arrayLoc =
1149 checkLocationFromExpressionNode(md, nametable, aan.getExpression(),
1150 new CompositeLocation(), constraint, isLHS);
1151 // addTypeLocation(aan.getExpression().getType(), arrayLoc);
1152 CompositeLocation indexLoc =
1153 checkLocationFromExpressionNode(md, nametable, aan.getIndex(), new CompositeLocation(),
1155 // addTypeLocation(aan.getIndex().getType(), indexLoc);
1158 if (!CompositeLattice.isGreaterThan(indexLoc, arrayLoc, generateErrorMessage(cd, aan))) {
1159 throw new Error("Array index value is not higher than array location at "
1160 + generateErrorMessage(cd, aan));
1164 Set<CompositeLocation> inputGLB = new HashSet<CompositeLocation>();
1165 inputGLB.add(arrayLoc);
1166 inputGLB.add(indexLoc);
1167 return CompositeLattice.calculateGLB(inputGLB, generateErrorMessage(cd, aan));
1172 private CompositeLocation checkLocationFromCreateObjectNode(MethodDescriptor md,
1173 SymbolTable nametable, CreateObjectNode con) {
1175 ClassDescriptor cd = md.getClassDesc();
1177 CompositeLocation compLoc = new CompositeLocation();
1178 compLoc.addLocation(Location.createTopLocation(md));
1183 private CompositeLocation checkLocationFromOpNode(MethodDescriptor md, SymbolTable nametable,
1184 OpNode on, CompositeLocation constraint) {
1186 ClassDescriptor cd = md.getClassDesc();
1187 CompositeLocation leftLoc = new CompositeLocation();
1189 checkLocationFromExpressionNode(md, nametable, on.getLeft(), leftLoc, constraint, false);
1190 // addTypeLocation(on.getLeft().getType(), leftLoc);
1192 CompositeLocation rightLoc = new CompositeLocation();
1193 if (on.getRight() != null) {
1195 checkLocationFromExpressionNode(md, nametable, on.getRight(), rightLoc, constraint, false);
1196 // addTypeLocation(on.getRight().getType(), rightLoc);
1199 // System.out.println("\n# OP NODE=" + on.printNode(0));
1200 // System.out.println("# left loc=" + leftLoc + " from " + on.getLeft().getClass());
1201 // if (on.getRight() != null) {
1202 // System.out.println("# right loc=" + rightLoc + " from " + on.getRight().getClass());
1205 Operation op = on.getOp();
1207 switch (op.getOp()) {
1209 case Operation.UNARYPLUS:
1210 case Operation.UNARYMINUS:
1211 case Operation.LOGIC_NOT:
1215 case Operation.LOGIC_OR:
1216 case Operation.LOGIC_AND:
1217 case Operation.COMP:
1218 case Operation.BIT_OR:
1219 case Operation.BIT_XOR:
1220 case Operation.BIT_AND:
1221 case Operation.ISAVAILABLE:
1222 case Operation.EQUAL:
1223 case Operation.NOTEQUAL:
1230 case Operation.MULT:
1233 case Operation.LEFTSHIFT:
1234 case Operation.RIGHTSHIFT:
1235 case Operation.URIGHTSHIFT:
1237 Set<CompositeLocation> inputSet = new HashSet<CompositeLocation>();
1238 inputSet.add(leftLoc);
1239 inputSet.add(rightLoc);
1240 CompositeLocation glbCompLoc =
1241 CompositeLattice.calculateGLB(inputSet, generateErrorMessage(cd, on));
1242 // System.out.println("# glbCompLoc=" + glbCompLoc);
1246 throw new Error(op.toString());
1251 private CompositeLocation checkLocationFromLiteralNode(MethodDescriptor md,
1252 SymbolTable nametable, LiteralNode en, CompositeLocation loc) {
1254 // literal value has the top location so that value can be flowed into any
1256 Location literalLoc = Location.createTopLocation(md);
1257 loc.addLocation(literalLoc);
1262 private CompositeLocation checkLocationFromNameNode(MethodDescriptor md, SymbolTable nametable,
1263 NameNode nn, CompositeLocation loc, CompositeLocation constraint) {
1265 NameDescriptor nd = nn.getName();
1266 if (nd.getBase() != null) {
1268 checkLocationFromExpressionNode(md, nametable, nn.getExpression(), loc, constraint, false);
1270 String varname = nd.toString();
1271 if (varname.equals("this")) {
1273 MethodLattice<String> methodLattice = ssjava.getMethodLattice(md);
1274 String thisLocId = methodLattice.getThisLoc();
1275 if (thisLocId == null) {
1276 throw new Error("The location for 'this' is not defined at "
1277 + md.getClassDesc().getSourceFileName() + "::" + nn.getNumLine());
1279 Location locElement = new Location(md, thisLocId);
1280 loc.addLocation(locElement);
1285 Descriptor d = (Descriptor) nametable.get(varname);
1287 // CompositeLocation localLoc = null;
1288 if (d instanceof VarDescriptor) {
1289 VarDescriptor vd = (VarDescriptor) d;
1290 // localLoc = d2loc.get(vd);
1291 // the type of var descriptor has a composite location!
1292 loc = ((CompositeLocation) vd.getType().getExtension()).clone();
1293 } else if (d instanceof FieldDescriptor) {
1294 // the type of field descriptor has a location!
1295 FieldDescriptor fd = (FieldDescriptor) d;
1296 if (fd.isStatic()) {
1298 // if it is 'static final', the location has TOP since no one can
1300 loc.addLocation(Location.createTopLocation(md));
1303 // if 'static', the location has pre-assigned global loc
1304 MethodLattice<String> localLattice = ssjava.getMethodLattice(md);
1305 String globalLocId = localLattice.getGlobalLoc();
1306 if (globalLocId == null) {
1307 throw new Error("Global location element is not defined in the method " + md);
1309 Location globalLoc = new Location(md, globalLocId);
1311 loc.addLocation(globalLoc);
1314 // the location of field access starts from this, followed by field
1316 MethodLattice<String> localLattice = ssjava.getMethodLattice(md);
1317 Location thisLoc = new Location(md, localLattice.getThisLoc());
1318 loc.addLocation(thisLoc);
1321 Location fieldLoc = (Location) fd.getType().getExtension();
1322 loc.addLocation(fieldLoc);
1323 } else if (d == null) {
1324 // access static field
1325 ClassDescriptor cd = nn.getClassDesc();
1327 MethodLattice<String> localLattice = ssjava.getMethodLattice(md);
1328 String globalLocId = localLattice.getGlobalLoc();
1329 if (globalLocId == null) {
1330 throw new Error("Method lattice does not define global variable location at "
1331 + generateErrorMessage(md.getClassDesc(), nn));
1333 loc.addLocation(new Location(md, globalLocId));
1341 private CompositeLocation checkLocationFromFieldAccessNode(MethodDescriptor md,
1342 SymbolTable nametable, FieldAccessNode fan, CompositeLocation loc,
1343 CompositeLocation constraint) {
1345 ExpressionNode left = fan.getExpression();
1346 TypeDescriptor ltd = left.getType();
1348 FieldDescriptor fd = fan.getField();
1350 String varName = null;
1351 if (left.kind() == Kind.NameNode) {
1352 NameDescriptor nd = ((NameNode) left).getName();
1353 varName = nd.toString();
1356 if (ltd.isClassNameRef() || (varName != null && varName.equals("this"))) {
1357 // using a class name directly or access using this
1358 if (fd.isStatic() && fd.isFinal()) {
1359 loc.addLocation(Location.createTopLocation(md));
1364 if (left instanceof ArrayAccessNode) {
1365 ArrayAccessNode aan = (ArrayAccessNode) left;
1366 left = aan.getExpression();
1369 loc = checkLocationFromExpressionNode(md, nametable, left, loc, constraint, false);
1370 // System.out.println("### checkLocationFromFieldAccessNode=" + fan.printNode(0));
1371 // System.out.println("### left=" + left.printNode(0));
1372 if (!left.getType().isPrimitive()) {
1373 Location fieldLoc = getFieldLocation(fd);
1374 loc.addLocation(fieldLoc);
1376 // System.out.println("### field loc=" + loc);
1380 private Location getFieldLocation(FieldDescriptor fd) {
1382 // System.out.println("### getFieldLocation=" + fd);
1383 // System.out.println("### fd.getType().getExtension()=" + fd.getType().getExtension());
1385 Location fieldLoc = (Location) fd.getType().getExtension();
1387 // handle the case that method annotation checking skips checking field
1389 if (fieldLoc == null) {
1390 fieldLoc = checkFieldDeclaration(fd.getClassDescriptor(), fd);
1397 private CompositeLocation checkLocationFromAssignmentNode(MethodDescriptor md,
1398 SymbolTable nametable, AssignmentNode an, CompositeLocation loc, CompositeLocation constraint) {
1400 // System.out.println("\n# ASSIGNMENTNODE=" + an.printNode(0));
1402 ClassDescriptor cd = md.getClassDesc();
1404 Set<CompositeLocation> inputGLBSet = new HashSet<CompositeLocation>();
1406 boolean postinc = true;
1407 if (an.getOperation().getBaseOp() == null
1408 || (an.getOperation().getBaseOp().getOp() != Operation.POSTINC && an.getOperation()
1409 .getBaseOp().getOp() != Operation.POSTDEC))
1412 // if LHS is array access node, need to check if array index is higher
1413 // than array itself
1414 CompositeLocation destLocation =
1415 checkLocationFromExpressionNode(md, nametable, an.getDest(), new CompositeLocation(),
1418 CompositeLocation rhsLocation;
1419 CompositeLocation srcLocation;
1423 checkLocationFromExpressionNode(md, nametable, an.getSrc(), new CompositeLocation(),
1426 srcLocation = rhsLocation;
1428 // if (!rhsLocation.get(rhsLocation.getSize() - 1).isTop()) {
1429 if (constraint != null) {
1430 inputGLBSet.add(rhsLocation);
1431 inputGLBSet.add(constraint);
1432 srcLocation = CompositeLattice.calculateGLB(inputGLBSet, generateErrorMessage(cd, an));
1436 // System.out.println("dstLocation=" + destLocation);
1437 // System.out.println("rhsLocation=" + rhsLocation);
1438 // System.out.println("srcLocation=" + srcLocation);
1439 // System.out.println("constraint=" + constraint);
1441 if (!CompositeLattice.isGreaterThan(srcLocation, destLocation, generateErrorMessage(cd, an))) {
1443 String context = "";
1444 if (constraint != null) {
1445 context = " and the current context constraint is " + constraint;
1448 throw new Error("The value flow from " + srcLocation + " to " + destLocation
1449 + " does not respect location hierarchy on the assignment " + an.printNode(0) + context
1450 + " at " + cd.getSourceFileName() + "::" + an.getNumLine());
1456 checkLocationFromExpressionNode(md, nametable, an.getDest(), new CompositeLocation(),
1459 if (constraint != null) {
1460 inputGLBSet.add(rhsLocation);
1461 inputGLBSet.add(constraint);
1462 srcLocation = CompositeLattice.calculateGLB(inputGLBSet, generateErrorMessage(cd, an));
1464 srcLocation = rhsLocation;
1467 // System.out.println("srcLocation=" + srcLocation);
1468 // System.out.println("rhsLocation=" + rhsLocation);
1469 // System.out.println("constraint=" + constraint);
1471 if (!CompositeLattice.isGreaterThan(srcLocation, destLocation, generateErrorMessage(cd, an))) {
1473 if (srcLocation.equals(destLocation)) {
1474 throw new Error("Location " + srcLocation
1475 + " is not allowed to have the value flow that moves within the same location at '"
1476 + an.printNode(0) + "' of " + cd.getSourceFileName() + "::" + an.getNumLine());
1478 throw new Error("The value flow from " + srcLocation + " to " + destLocation
1479 + " does not respect location hierarchy on the assignment " + an.printNode(0)
1480 + " at " + cd.getSourceFileName() + "::" + an.getNumLine());
1487 return destLocation;
1490 private void assignLocationOfVarDescriptor(VarDescriptor vd, MethodDescriptor md,
1491 SymbolTable nametable, TreeNode n) {
1493 ClassDescriptor cd = md.getClassDesc();
1494 Vector<AnnotationDescriptor> annotationVec = vd.getType().getAnnotationMarkers();
1496 // currently enforce every variable to have corresponding location
1497 if (annotationVec.size() == 0) {
1498 throw new Error("Location is not assigned to variable '" + vd.getSymbol()
1499 + "' in the method '" + md + "' of the class " + cd.getSymbol() + " at "
1500 + generateErrorMessage(cd, n));
1503 if (annotationVec.size() > 1) { // variable can have at most one location
1504 throw new Error(vd.getSymbol() + " has more than one location.");
1507 AnnotationDescriptor ad = annotationVec.elementAt(0);
1509 if (ad.getType() == AnnotationDescriptor.SINGLE_ANNOTATION) {
1511 if (ad.getMarker().equals(SSJavaAnalysis.LOC)) {
1512 String locDec = ad.getValue(); // check if location is defined
1514 if (locDec.startsWith(SSJavaAnalysis.DELTA)) {
1515 DeltaLocation deltaLoc = parseDeltaDeclaration(md, n, locDec);
1516 d2loc.put(vd, deltaLoc);
1517 addLocationType(vd.getType(), deltaLoc);
1519 CompositeLocation compLoc = parseLocationDeclaration(md, n, locDec);
1521 Location lastElement = compLoc.get(compLoc.getSize() - 1);
1522 if (ssjava.isSharedLocation(lastElement)) {
1523 ssjava.mapSharedLocation2Descriptor(lastElement, vd);
1526 d2loc.put(vd, compLoc);
1527 addLocationType(vd.getType(), compLoc);
1535 private DeltaLocation parseDeltaDeclaration(MethodDescriptor md, TreeNode n, String locDec) {
1538 int dIdx = locDec.indexOf(SSJavaAnalysis.DELTA);
1541 int beginIdx = dIdx + 6;
1542 locDec = locDec.substring(beginIdx, locDec.length() - 1);
1543 dIdx = locDec.indexOf(SSJavaAnalysis.DELTA);
1546 CompositeLocation compLoc = parseLocationDeclaration(md, n, locDec);
1547 DeltaLocation deltaLoc = new DeltaLocation(compLoc, deltaCount);
1552 private Location parseFieldLocDeclaraton(String decl, String msg) throws Exception {
1554 int idx = decl.indexOf(".");
1556 String className = decl.substring(0, idx);
1557 String fieldName = decl.substring(idx + 1);
1559 className.replaceAll(" ", "");
1560 fieldName.replaceAll(" ", "");
1562 Descriptor d = state.getClassSymbolTable().get(className);
1565 // System.out.println("state.getClassSymbolTable()=" + state.getClassSymbolTable());
1566 throw new Error("The class in the location declaration '" + decl + "' does not exist at "
1570 assert (d instanceof ClassDescriptor);
1571 SSJavaLattice<String> lattice = ssjava.getClassLattice((ClassDescriptor) d);
1572 if (!lattice.containsKey(fieldName)) {
1573 throw new Error("The location " + fieldName + " is not defined in the field lattice of '"
1574 + className + "' at " + msg);
1577 return new Location(d, fieldName);
1580 private CompositeLocation parseLocationDeclaration(MethodDescriptor md, TreeNode n, String locDec) {
1582 CompositeLocation compLoc = new CompositeLocation();
1584 StringTokenizer tokenizer = new StringTokenizer(locDec, ",");
1585 List<String> locIdList = new ArrayList<String>();
1586 while (tokenizer.hasMoreTokens()) {
1587 String locId = tokenizer.nextToken();
1588 locIdList.add(locId);
1591 // at least,one location element needs to be here!
1592 assert (locIdList.size() > 0);
1594 // assume that loc with idx 0 comes from the local lattice
1595 // loc with idx 1 comes from the field lattice
1597 String localLocId = locIdList.get(0);
1598 SSJavaLattice<String> localLattice = CompositeLattice.getLatticeByDescriptor(md);
1599 Location localLoc = new Location(md, localLocId);
1600 if (localLattice == null || (!localLattice.containsKey(localLocId))) {
1601 throw new Error("Location " + localLocId
1602 + " is not defined in the local variable lattice at "
1603 + md.getClassDesc().getSourceFileName() + "::" + (n != null ? n.getNumLine() : md) + ".");
1605 compLoc.addLocation(localLoc);
1607 for (int i = 1; i < locIdList.size(); i++) {
1608 String locName = locIdList.get(i);
1611 parseFieldLocDeclaraton(locName, generateErrorMessage(md.getClassDesc(), n));
1612 compLoc.addLocation(fieldLoc);
1613 } catch (Exception e) {
1614 throw new Error("The location declaration '" + locName + "' is wrong at "
1615 + generateErrorMessage(md.getClassDesc(), n));
1623 private void checkDeclarationNode(MethodDescriptor md, SymbolTable nametable, DeclarationNode dn) {
1624 VarDescriptor vd = dn.getVarDescriptor();
1625 assignLocationOfVarDescriptor(vd, md, nametable, dn);
1628 private void checkDeclarationInClass(ClassDescriptor cd) {
1629 // Check to see that fields are okay
1630 for (Iterator field_it = cd.getFields(); field_it.hasNext();) {
1631 FieldDescriptor fd = (FieldDescriptor) field_it.next();
1633 if (!(fd.isFinal() && fd.isStatic())) {
1634 checkFieldDeclaration(cd, fd);
1636 // for static final, assign top location by default
1637 Location loc = Location.createTopLocation(cd);
1638 addLocationType(fd.getType(), loc);
1643 private Location checkFieldDeclaration(ClassDescriptor cd, FieldDescriptor fd) {
1645 Vector<AnnotationDescriptor> annotationVec = fd.getType().getAnnotationMarkers();
1647 // currently enforce every field to have corresponding location
1648 if (annotationVec.size() == 0) {
1649 throw new Error("Location is not assigned to the field '" + fd.getSymbol()
1650 + "' of the class " + cd.getSymbol() + " at " + cd.getSourceFileName());
1653 if (annotationVec.size() > 1) {
1654 // variable can have at most one location
1655 throw new Error("Field " + fd.getSymbol() + " of class " + cd
1656 + " has more than one location.");
1659 AnnotationDescriptor ad = annotationVec.elementAt(0);
1660 Location loc = null;
1662 if (ad.getType() == AnnotationDescriptor.SINGLE_ANNOTATION) {
1663 if (ad.getMarker().equals(SSJavaAnalysis.LOC)) {
1664 String locationID = ad.getValue();
1665 // check if location is defined
1666 SSJavaLattice<String> lattice = ssjava.getClassLattice(cd);
1667 if (lattice == null || (!lattice.containsKey(locationID))) {
1668 throw new Error("Location " + locationID
1669 + " is not defined in the field lattice of class " + cd.getSymbol() + " at"
1670 + cd.getSourceFileName() + ".");
1672 loc = new Location(cd, locationID);
1674 if (ssjava.isSharedLocation(loc)) {
1675 ssjava.mapSharedLocation2Descriptor(loc, fd);
1678 addLocationType(fd.getType(), loc);
1686 private void addLocationType(TypeDescriptor type, CompositeLocation loc) {
1688 type.setExtension(loc);
1692 private void addLocationType(TypeDescriptor type, Location loc) {
1694 type.setExtension(loc);
1698 static class CompositeLattice {
1700 public static boolean isGreaterThan(CompositeLocation loc1, CompositeLocation loc2, String msg) {
1702 // System.out.println("\nisGreaterThan=" + loc1 + " " + loc2 + " msg=" + msg);
1703 int baseCompareResult = compareBaseLocationSet(loc1, loc2, true, false, msg);
1704 if (baseCompareResult == ComparisonResult.EQUAL) {
1705 if (compareDelta(loc1, loc2) == ComparisonResult.GREATER) {
1710 } else if (baseCompareResult == ComparisonResult.GREATER) {
1718 public static int compare(CompositeLocation loc1, CompositeLocation loc2, boolean ignore,
1721 // System.out.println("compare=" + loc1 + " " + loc2);
1722 int baseCompareResult = compareBaseLocationSet(loc1, loc2, false, ignore, msg);
1724 if (baseCompareResult == ComparisonResult.EQUAL) {
1725 return compareDelta(loc1, loc2);
1727 return baseCompareResult;
1732 private static int compareDelta(CompositeLocation dLoc1, CompositeLocation dLoc2) {
1734 int deltaCount1 = 0;
1735 int deltaCount2 = 0;
1736 if (dLoc1 instanceof DeltaLocation) {
1737 deltaCount1 = ((DeltaLocation) dLoc1).getNumDelta();
1740 if (dLoc2 instanceof DeltaLocation) {
1741 deltaCount2 = ((DeltaLocation) dLoc2).getNumDelta();
1743 if (deltaCount1 < deltaCount2) {
1744 return ComparisonResult.GREATER;
1745 } else if (deltaCount1 == deltaCount2) {
1746 return ComparisonResult.EQUAL;
1748 return ComparisonResult.LESS;
1753 private static int compareBaseLocationSet(CompositeLocation compLoc1,
1754 CompositeLocation compLoc2, boolean awareSharedLoc, boolean ignore, String msg) {
1756 // if compLoc1 is greater than compLoc2, return true
1757 // else return false;
1759 // compare one by one in according to the order of the tuple
1761 for (int i = 0; i < compLoc1.getSize(); i++) {
1762 Location loc1 = compLoc1.get(i);
1763 if (i >= compLoc2.getSize()) {
1765 return ComparisonResult.INCOMPARABLE;
1767 throw new Error("Failed to compare two locations of " + compLoc1 + " and " + compLoc2
1768 + " because they are not comparable at " + msg);
1771 Location loc2 = compLoc2.get(i);
1773 Descriptor descriptor = getCommonParentDescriptor(loc1, loc2, msg);
1774 SSJavaLattice<String> lattice = getLatticeByDescriptor(descriptor);
1776 // check if the shared location is appeared only at the end of the
1777 // composite location
1778 if (lattice.getSharedLocSet().contains(loc1.getLocIdentifier())) {
1779 if (i != (compLoc1.getSize() - 1)) {
1780 throw new Error("The shared location " + loc1.getLocIdentifier()
1781 + " cannot be appeared in the middle of composite location at" + msg);
1785 if (lattice.getSharedLocSet().contains(loc2.getLocIdentifier())) {
1786 if (i != (compLoc2.getSize() - 1)) {
1787 throw new Error("The shared location " + loc2.getLocIdentifier()
1788 + " cannot be appeared in the middle of composite location at " + msg);
1792 // if (!lattice1.equals(lattice2)) {
1793 // throw new Error("Failed to compare two locations of " + compLoc1 +
1794 // " and " + compLoc2
1795 // + " because they are not comparable at " + msg);
1798 if (loc1.getLocIdentifier().equals(loc2.getLocIdentifier())) {
1800 // check if the current location is the spinning location
1801 // note that the spinning location only can be appeared in the last
1802 // part of the composite location
1803 if (awareSharedLoc && numOfTie == compLoc1.getSize()
1804 && lattice.getSharedLocSet().contains(loc1.getLocIdentifier())) {
1805 return ComparisonResult.GREATER;
1808 } else if (lattice.isGreaterThan(loc1.getLocIdentifier(), loc2.getLocIdentifier())) {
1809 return ComparisonResult.GREATER;
1811 return ComparisonResult.LESS;
1816 if (numOfTie == compLoc1.getSize()) {
1818 if (numOfTie != compLoc2.getSize()) {
1821 return ComparisonResult.INCOMPARABLE;
1823 throw new Error("Failed to compare two locations of " + compLoc1 + " and " + compLoc2
1824 + " because they are not comparable at " + msg);
1829 return ComparisonResult.EQUAL;
1832 return ComparisonResult.LESS;
1836 public static CompositeLocation calculateGLB(Set<CompositeLocation> inputSet, String errMsg) {
1838 // System.out.println("Calculating GLB=" + inputSet);
1839 CompositeLocation glbCompLoc = new CompositeLocation();
1841 // calculate GLB of the first(priority) element
1842 Set<String> priorityLocIdentifierSet = new HashSet<String>();
1843 Descriptor priorityDescriptor = null;
1845 Hashtable<String, Set<CompositeLocation>> locId2CompLocSet =
1846 new Hashtable<String, Set<CompositeLocation>>();
1847 // mapping from the priority loc ID to its full representation by the
1848 // composite location
1850 int maxTupleSize = 0;
1851 CompositeLocation maxCompLoc = null;
1853 Location prevPriorityLoc = null;
1854 for (Iterator iterator = inputSet.iterator(); iterator.hasNext();) {
1855 CompositeLocation compLoc = (CompositeLocation) iterator.next();
1856 if (compLoc.getSize() > maxTupleSize) {
1857 maxTupleSize = compLoc.getSize();
1858 maxCompLoc = compLoc;
1860 Location priorityLoc = compLoc.get(0);
1861 String priorityLocId = priorityLoc.getLocIdentifier();
1862 priorityLocIdentifierSet.add(priorityLocId);
1864 if (locId2CompLocSet.containsKey(priorityLocId)) {
1865 locId2CompLocSet.get(priorityLocId).add(compLoc);
1867 Set<CompositeLocation> newSet = new HashSet<CompositeLocation>();
1868 newSet.add(compLoc);
1869 locId2CompLocSet.put(priorityLocId, newSet);
1872 // check if priority location are coming from the same lattice
1873 if (priorityDescriptor == null) {
1874 priorityDescriptor = priorityLoc.getDescriptor();
1876 priorityDescriptor = getCommonParentDescriptor(priorityLoc, prevPriorityLoc, errMsg);
1878 prevPriorityLoc = priorityLoc;
1879 // else if (!priorityDescriptor.equals(priorityLoc.getDescriptor())) {
1880 // throw new Error("Failed to calculate GLB of " + inputSet
1881 // + " because they are from different lattices.");
1885 SSJavaLattice<String> locOrder = getLatticeByDescriptor(priorityDescriptor);
1886 String glbOfPriorityLoc = locOrder.getGLB(priorityLocIdentifierSet);
1888 glbCompLoc.addLocation(new Location(priorityDescriptor, glbOfPriorityLoc));
1889 Set<CompositeLocation> compSet = locId2CompLocSet.get(glbOfPriorityLoc);
1891 if (compSet == null) {
1892 // when GLB(x1,x2)!=x1 and !=x2 : GLB case 4
1893 // mean that the result is already lower than <x1,y1> and <x2,y2>
1894 // assign TOP to the rest of the location elements
1896 // in this case, do not take care about delta
1897 // CompositeLocation inputComp = inputSet.iterator().next();
1898 for (int i = 1; i < maxTupleSize; i++) {
1899 glbCompLoc.addLocation(Location.createTopLocation(maxCompLoc.get(i).getDescriptor()));
1903 // here find out composite location that has a maximum length tuple
1904 // if we have three input set: [A], [A,B], [A,B,C]
1905 // maximum length tuple will be [A,B,C]
1907 CompositeLocation maxFromCompSet = null;
1908 for (Iterator iterator = compSet.iterator(); iterator.hasNext();) {
1909 CompositeLocation c = (CompositeLocation) iterator.next();
1910 if (c.getSize() > max) {
1916 if (compSet.size() == 1) {
1917 // if GLB(x1,x2)==x1 or x2 : GLB case 2,3
1918 CompositeLocation comp = compSet.iterator().next();
1919 for (int i = 1; i < comp.getSize(); i++) {
1920 glbCompLoc.addLocation(comp.get(i));
1923 // if input location corresponding to glb is a delta, need to apply
1924 // delta to glb result
1925 if (comp instanceof DeltaLocation) {
1926 glbCompLoc = new DeltaLocation(glbCompLoc, 1);
1930 // when GLB(x1,x2)==x1 and x2 : GLB case 1
1931 // if more than one location shares the same priority GLB
1932 // need to calculate the rest of GLB loc
1934 // setup input set starting from the second tuple item
1935 Set<CompositeLocation> innerGLBInput = new HashSet<CompositeLocation>();
1936 for (Iterator iterator = compSet.iterator(); iterator.hasNext();) {
1937 CompositeLocation compLoc = (CompositeLocation) iterator.next();
1938 CompositeLocation innerCompLoc = new CompositeLocation();
1939 for (int idx = 1; idx < compLoc.getSize(); idx++) {
1940 innerCompLoc.addLocation(compLoc.get(idx));
1942 if (innerCompLoc.getSize() > 0) {
1943 innerGLBInput.add(innerCompLoc);
1947 if (innerGLBInput.size() > 0) {
1948 CompositeLocation innerGLB = CompositeLattice.calculateGLB(innerGLBInput, errMsg);
1949 for (int idx = 0; idx < innerGLB.getSize(); idx++) {
1950 glbCompLoc.addLocation(innerGLB.get(idx));
1954 // if input location corresponding to glb is a delta, need to apply
1955 // delta to glb result
1957 for (Iterator iterator = compSet.iterator(); iterator.hasNext();) {
1958 CompositeLocation compLoc = (CompositeLocation) iterator.next();
1959 if (compLoc instanceof DeltaLocation) {
1960 if (glbCompLoc.equals(compLoc)) {
1961 glbCompLoc = new DeltaLocation(glbCompLoc, 1);
1970 // System.out.println("GLB=" + glbCompLoc);
1975 static SSJavaLattice<String> getLatticeByDescriptor(Descriptor d) {
1977 SSJavaLattice<String> lattice = null;
1979 if (d instanceof ClassDescriptor) {
1980 lattice = ssjava.getCd2lattice().get(d);
1981 } else if (d instanceof MethodDescriptor) {
1982 if (ssjava.getMd2lattice().containsKey(d)) {
1983 lattice = ssjava.getMd2lattice().get(d);
1985 // use default lattice for the method
1986 lattice = ssjava.getCd2methodDefault().get(((MethodDescriptor) d).getClassDesc());
1993 static Descriptor getCommonParentDescriptor(Location loc1, Location loc2, String msg) {
1995 Descriptor d1 = loc1.getDescriptor();
1996 Descriptor d2 = loc2.getDescriptor();
1998 Descriptor descriptor;
2000 if (d1 instanceof ClassDescriptor && d2 instanceof ClassDescriptor) {
2002 if (d1.equals(d2)) {
2005 // identifying which one is parent class
2006 Set<Descriptor> d1SubClassesSet = ssjava.tu.getSubClasses((ClassDescriptor) d1);
2007 Set<Descriptor> d2SubClassesSet = ssjava.tu.getSubClasses((ClassDescriptor) d2);
2009 if (d1 == null && d2 == null) {
2010 throw new Error("Failed to compare two locations of " + loc1 + " and " + loc2
2011 + " because they are not comparable at " + msg);
2012 } else if (d1SubClassesSet != null && d1SubClassesSet.contains(d2)) {
2014 } else if (d2SubClassesSet != null && d2SubClassesSet.contains(d1)) {
2017 throw new Error("Failed to compare two locations of " + loc1 + " and " + loc2
2018 + " because they are not comparable at " + msg);
2022 } else if (d1 instanceof MethodDescriptor && d2 instanceof MethodDescriptor) {
2024 if (d1.equals(d2)) {
2028 // identifying which one is parent class
2029 MethodDescriptor md1 = (MethodDescriptor) d1;
2030 MethodDescriptor md2 = (MethodDescriptor) d2;
2032 if (!md1.matches(md2)) {
2033 throw new Error("Failed to compare two locations of " + loc1 + " and " + loc2
2034 + " because they are not comparable at " + msg);
2037 Set<Descriptor> d1SubClassesSet =
2038 ssjava.tu.getSubClasses(((MethodDescriptor) d1).getClassDesc());
2039 Set<Descriptor> d2SubClassesSet =
2040 ssjava.tu.getSubClasses(((MethodDescriptor) d2).getClassDesc());
2042 if (d1 == null && d2 == null) {
2043 throw new Error("Failed to compare two locations of " + loc1 + " and " + loc2
2044 + " because they are not comparable at " + msg);
2045 } else if (d1 != null && d1SubClassesSet.contains(d2)) {
2047 } else if (d2 != null && d2SubClassesSet.contains(d1)) {
2050 throw new Error("Failed to compare two locations of " + loc1 + " and " + loc2
2051 + " because they are not comparable at " + msg);
2056 throw new Error("Failed to compare two locations of " + loc1 + " and " + loc2
2057 + " because they are not comparable at " + msg);
2066 class ComparisonResult {
2068 public static final int GREATER = 0;
2069 public static final int EQUAL = 1;
2070 public static final int LESS = 2;
2071 public static final int INCOMPARABLE = 3;
2078 class ReturnLocGenerator {
2080 public static final int PARAMISHIGHER = 0;
2081 public static final int PARAMISSAME = 1;
2082 public static final int IGNORE = 2;
2084 private Hashtable<Integer, Integer> paramIdx2paramType;
2086 private CompositeLocation declaredReturnLoc = null;
2088 public ReturnLocGenerator(CompositeLocation returnLoc, MethodDescriptor md,
2089 List<CompositeLocation> params, String msg) {
2091 CompositeLocation thisLoc = params.get(0);
2092 if (returnLoc.get(0).equals(thisLoc.get(0)) && returnLoc.getSize() > 1) {
2093 // if the declared return location consists of THIS and field location,
2094 // return location for the caller's side has to have same field element
2095 this.declaredReturnLoc = returnLoc;
2097 // creating mappings
2098 paramIdx2paramType = new Hashtable<Integer, Integer>();
2099 for (int i = 0; i < params.size(); i++) {
2100 CompositeLocation param = params.get(i);
2101 int compareResult = CompositeLattice.compare(param, returnLoc, true, msg);
2104 if (compareResult == ComparisonResult.GREATER) {
2106 } else if (compareResult == ComparisonResult.EQUAL) {
2111 paramIdx2paramType.put(new Integer(i), new Integer(type));
2117 public CompositeLocation computeReturnLocation(List<CompositeLocation> args) {
2119 if (declaredReturnLoc != null) {
2120 // when developer specify that the return value is [THIS,field]
2121 // needs to translate to the caller's location
2122 CompositeLocation callerLoc = new CompositeLocation();
2123 CompositeLocation callerBaseLocation = args.get(0);
2125 for (int i = 0; i < callerBaseLocation.getSize(); i++) {
2126 callerLoc.addLocation(callerBaseLocation.get(i));
2128 for (int i = 1; i < declaredReturnLoc.getSize(); i++) {
2129 callerLoc.addLocation(declaredReturnLoc.get(i));
2133 // compute the highest possible location in caller's side
2134 assert paramIdx2paramType.keySet().size() == args.size();
2136 Set<CompositeLocation> inputGLB = new HashSet<CompositeLocation>();
2137 for (int i = 0; i < args.size(); i++) {
2138 int type = (paramIdx2paramType.get(new Integer(i))).intValue();
2139 CompositeLocation argLoc = args.get(i);
2140 if (type == PARAMISHIGHER || type == PARAMISSAME) {
2141 // return loc is equal to or lower than param
2142 inputGLB.add(argLoc);
2146 // compute GLB of arguments subset that are same or higher than return
2148 if (inputGLB.isEmpty()) {
2149 CompositeLocation rtr =
2150 new CompositeLocation(Location.createTopLocation(args.get(0).get(0).getDescriptor()));
2153 CompositeLocation glb = CompositeLattice.calculateGLB(inputGLB, "");