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().compareTo(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().compareTo(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);
295 System.out.println("\n#checkDeclarationInMethodBody=" + md);
297 // first, check annotations on method parameters
298 List<CompositeLocation> paramList = new ArrayList<CompositeLocation>();
299 for (int i = 0; i < md.numParameters(); i++) {
300 // process annotations on method parameters
301 VarDescriptor vd = (VarDescriptor) md.getParameter(i);
302 assignLocationOfVarDescriptor(vd, md, md.getParameterTable(), null);
303 paramList.add(d2loc.get(vd));
305 Vector<AnnotationDescriptor> methodAnnotations = md.getModifiers().getAnnotations();
307 // second, check return location annotation
308 if (!md.getReturnType().isVoid()) {
309 CompositeLocation returnLocComp = null;
311 boolean hasReturnLocDeclaration = false;
312 if (methodAnnotations != null) {
313 for (int i = 0; i < methodAnnotations.size(); i++) {
314 AnnotationDescriptor an = methodAnnotations.elementAt(i);
315 if (an.getMarker().equals(ssjava.RETURNLOC)) {
316 // this case, developer explicitly defines method lattice
317 String returnLocDeclaration = an.getValue();
318 returnLocComp = parseLocationDeclaration(md, null, returnLocDeclaration);
319 hasReturnLocDeclaration = true;
324 if (!hasReturnLocDeclaration) {
325 // if developer does not define method lattice
326 // search return location in the method default lattice
327 String rtrStr = ssjava.getMethodLattice(md).getReturnLoc();
329 returnLocComp = new CompositeLocation(new Location(md, rtrStr));
333 if (returnLocComp == null) {
334 throw new Error("Return location is not specified for the method " + md + " at "
335 + cd.getSourceFileName());
338 md2ReturnLoc.put(md, returnLocComp);
340 // check this location
341 MethodLattice<String> methodLattice = ssjava.getMethodLattice(md);
342 String thisLocId = methodLattice.getThisLoc();
343 if (thisLocId == null) {
344 throw new Error("Method '" + md + "' does not have the definition of 'this' location at "
345 + md.getClassDesc().getSourceFileName());
347 CompositeLocation thisLoc = new CompositeLocation(new Location(md, thisLocId));
348 paramList.add(0, thisLoc);
350 System.out.println("### ReturnLocGenerator=" + md);
351 System.out.println("### md2ReturnLoc.get(md)=" + md2ReturnLoc.get(md));
353 md2ReturnLocGen.put(md, new ReturnLocGenerator(md2ReturnLoc.get(md), md, paramList, md
354 + " of " + cd.getSourceFileName()));
357 // fourth, check declarations inside of method
359 checkDeclarationInBlockNode(md, md.getParameterTable(), bn);
363 private void checkDeclarationInBlockNode(MethodDescriptor md, SymbolTable nametable, BlockNode bn) {
364 bn.getVarTable().setParent(nametable);
365 for (int i = 0; i < bn.size(); i++) {
366 BlockStatementNode bsn = bn.get(i);
367 checkDeclarationInBlockStatementNode(md, bn.getVarTable(), bsn);
371 private void checkDeclarationInBlockStatementNode(MethodDescriptor md, SymbolTable nametable,
372 BlockStatementNode bsn) {
374 switch (bsn.kind()) {
375 case Kind.SubBlockNode:
376 checkDeclarationInSubBlockNode(md, nametable, (SubBlockNode) bsn);
379 case Kind.DeclarationNode:
380 checkDeclarationNode(md, nametable, (DeclarationNode) bsn);
384 checkDeclarationInLoopNode(md, nametable, (LoopNode) bsn);
387 case Kind.IfStatementNode:
388 checkDeclarationInIfStatementNode(md, nametable, (IfStatementNode) bsn);
391 case Kind.SwitchStatementNode:
392 checkDeclarationInSwitchStatementNode(md, nametable, (SwitchStatementNode) bsn);
395 case Kind.SynchronizedNode:
396 checkDeclarationInSynchronizedNode(md, nametable, (SynchronizedNode) bsn);
402 private void checkDeclarationInSynchronizedNode(MethodDescriptor md, SymbolTable nametable,
403 SynchronizedNode sbn) {
404 checkDeclarationInBlockNode(md, nametable, sbn.getBlockNode());
407 private void checkDeclarationInSwitchStatementNode(MethodDescriptor md, SymbolTable nametable,
408 SwitchStatementNode ssn) {
409 BlockNode sbn = ssn.getSwitchBody();
410 for (int i = 0; i < sbn.size(); i++) {
411 SwitchBlockNode node = (SwitchBlockNode) sbn.get(i);
412 checkDeclarationInBlockNode(md, nametable, node.getSwitchBlockStatement());
416 private void checkDeclarationInIfStatementNode(MethodDescriptor md, SymbolTable nametable,
417 IfStatementNode isn) {
418 checkDeclarationInBlockNode(md, nametable, isn.getTrueBlock());
419 if (isn.getFalseBlock() != null)
420 checkDeclarationInBlockNode(md, nametable, isn.getFalseBlock());
423 private void checkDeclarationInLoopNode(MethodDescriptor md, SymbolTable nametable, LoopNode ln) {
425 if (ln.getType() == LoopNode.FORLOOP) {
426 // check for loop case
427 ClassDescriptor cd = md.getClassDesc();
428 BlockNode bn = ln.getInitializer();
429 for (int i = 0; i < bn.size(); i++) {
430 BlockStatementNode bsn = bn.get(i);
431 checkDeclarationInBlockStatementNode(md, nametable, bsn);
436 checkDeclarationInBlockNode(md, nametable, ln.getBody());
439 private void checkMethodBody(ClassDescriptor cd, MethodDescriptor md,
440 CompositeLocation constraints) {
441 BlockNode bn = state.getMethodBody(md);
442 checkLocationFromBlockNode(md, md.getParameterTable(), bn, constraints);
445 private String generateErrorMessage(ClassDescriptor cd, TreeNode tn) {
447 return cd.getSourceFileName() + "::" + tn.getNumLine();
449 return cd.getSourceFileName();
454 private CompositeLocation checkLocationFromBlockNode(MethodDescriptor md, SymbolTable nametable,
455 BlockNode bn, CompositeLocation constraint) {
457 bn.getVarTable().setParent(nametable);
458 for (int i = 0; i < bn.size(); i++) {
459 BlockStatementNode bsn = bn.get(i);
460 checkLocationFromBlockStatementNode(md, bn.getVarTable(), bsn, constraint);
462 return new CompositeLocation();
466 private CompositeLocation checkLocationFromBlockStatementNode(MethodDescriptor md,
467 SymbolTable nametable, BlockStatementNode bsn, CompositeLocation constraint) {
469 CompositeLocation compLoc = null;
470 switch (bsn.kind()) {
471 case Kind.BlockExpressionNode:
473 checkLocationFromBlockExpressionNode(md, nametable, (BlockExpressionNode) bsn, constraint);
476 case Kind.DeclarationNode:
477 compLoc = checkLocationFromDeclarationNode(md, nametable, (DeclarationNode) bsn, constraint);
480 case Kind.IfStatementNode:
481 compLoc = checkLocationFromIfStatementNode(md, nametable, (IfStatementNode) bsn, constraint);
485 compLoc = checkLocationFromLoopNode(md, nametable, (LoopNode) bsn, constraint);
488 case Kind.ReturnNode:
489 compLoc = checkLocationFromReturnNode(md, nametable, (ReturnNode) bsn, constraint);
492 case Kind.SubBlockNode:
493 compLoc = checkLocationFromSubBlockNode(md, nametable, (SubBlockNode) bsn, constraint);
496 case Kind.ContinueBreakNode:
497 compLoc = new CompositeLocation();
500 case Kind.SwitchStatementNode:
502 checkLocationFromSwitchStatementNode(md, nametable, (SwitchStatementNode) bsn, constraint);
508 private CompositeLocation checkLocationFromSwitchStatementNode(MethodDescriptor md,
509 SymbolTable nametable, SwitchStatementNode ssn, CompositeLocation constraint) {
511 ClassDescriptor cd = md.getClassDesc();
512 CompositeLocation condLoc =
513 checkLocationFromExpressionNode(md, nametable, ssn.getCondition(), new CompositeLocation(),
515 BlockNode sbn = ssn.getSwitchBody();
517 constraint = generateNewConstraint(constraint, condLoc);
519 for (int i = 0; i < sbn.size(); i++) {
520 checkLocationFromSwitchBlockNode(md, nametable, (SwitchBlockNode) sbn.get(i), constraint);
522 return new CompositeLocation();
525 private CompositeLocation checkLocationFromSwitchBlockNode(MethodDescriptor md,
526 SymbolTable nametable, SwitchBlockNode sbn, CompositeLocation constraint) {
528 CompositeLocation blockLoc =
529 checkLocationFromBlockNode(md, nametable, sbn.getSwitchBlockStatement(), constraint);
535 private CompositeLocation checkLocationFromReturnNode(MethodDescriptor md, SymbolTable nametable,
536 ReturnNode rn, CompositeLocation constraint) {
538 ExpressionNode returnExp = rn.getReturnExpression();
540 CompositeLocation returnValueLoc;
541 if (returnExp != null) {
543 checkLocationFromExpressionNode(md, nametable, returnExp, new CompositeLocation(),
546 // if this return statement is inside branch, return value has an implicit
547 // flow from conditional location
548 if (constraint != null) {
549 Set<CompositeLocation> inputGLB = new HashSet<CompositeLocation>();
550 inputGLB.add(returnValueLoc);
551 inputGLB.add(constraint);
553 CompositeLattice.calculateGLB(inputGLB, generateErrorMessage(md.getClassDesc(), rn));
556 // check if return value is equal or higher than RETRUNLOC of method
557 // declaration annotation
558 CompositeLocation declaredReturnLoc = md2ReturnLoc.get(md);
561 CompositeLattice.compare(returnValueLoc, declaredReturnLoc, false,
562 generateErrorMessage(md.getClassDesc(), rn));
564 if (compareResult == ComparisonResult.LESS || compareResult == ComparisonResult.INCOMPARABLE) {
566 "Return value location is not equal or higher than the declaraed return location at "
567 + md.getClassDesc().getSourceFileName() + "::" + rn.getNumLine());
571 return new CompositeLocation();
574 private boolean hasOnlyLiteralValue(ExpressionNode en) {
575 if (en.kind() == Kind.LiteralNode) {
582 private CompositeLocation checkLocationFromLoopNode(MethodDescriptor md, SymbolTable nametable,
583 LoopNode ln, CompositeLocation constraint) {
585 ClassDescriptor cd = md.getClassDesc();
586 if (ln.getType() == LoopNode.WHILELOOP || ln.getType() == LoopNode.DOWHILELOOP) {
588 CompositeLocation condLoc =
589 checkLocationFromExpressionNode(md, nametable, ln.getCondition(),
590 new CompositeLocation(), constraint, false);
591 // addLocationType(ln.getCondition().getType(), (condLoc));
593 constraint = generateNewConstraint(constraint, condLoc);
594 checkLocationFromBlockNode(md, nametable, ln.getBody(), constraint);
596 return new CompositeLocation();
599 // check 'for loop' case
600 BlockNode bn = ln.getInitializer();
601 bn.getVarTable().setParent(nametable);
603 // calculate glb location of condition and update statements
604 CompositeLocation condLoc =
605 checkLocationFromExpressionNode(md, bn.getVarTable(), ln.getCondition(),
606 new CompositeLocation(), constraint, false);
607 // addLocationType(ln.getCondition().getType(), condLoc);
609 constraint = generateNewConstraint(constraint, condLoc);
611 checkLocationFromBlockNode(md, bn.getVarTable(), ln.getUpdate(), constraint);
612 checkLocationFromBlockNode(md, bn.getVarTable(), ln.getBody(), constraint);
614 return new CompositeLocation();
620 private CompositeLocation checkLocationFromSubBlockNode(MethodDescriptor md,
621 SymbolTable nametable, SubBlockNode sbn, CompositeLocation constraint) {
622 CompositeLocation compLoc =
623 checkLocationFromBlockNode(md, nametable, sbn.getBlockNode(), constraint);
627 private CompositeLocation generateNewConstraint(CompositeLocation currentCon,
628 CompositeLocation newCon) {
630 if (currentCon == null) {
633 // compute GLB of current constraint and new constraint
634 Set<CompositeLocation> inputSet = new HashSet<CompositeLocation>();
635 inputSet.add(currentCon);
636 inputSet.add(newCon);
637 return CompositeLattice.calculateGLB(inputSet, "");
642 private CompositeLocation checkLocationFromIfStatementNode(MethodDescriptor md,
643 SymbolTable nametable, IfStatementNode isn, CompositeLocation constraint) {
645 CompositeLocation condLoc =
646 checkLocationFromExpressionNode(md, nametable, isn.getCondition(), new CompositeLocation(),
649 // addLocationType(isn.getCondition().getType(), condLoc);
651 constraint = generateNewConstraint(constraint, condLoc);
652 checkLocationFromBlockNode(md, nametable, isn.getTrueBlock(), constraint);
654 if (isn.getFalseBlock() != null) {
655 checkLocationFromBlockNode(md, nametable, isn.getFalseBlock(), constraint);
658 return new CompositeLocation();
661 private CompositeLocation checkLocationFromDeclarationNode(MethodDescriptor md,
662 SymbolTable nametable, DeclarationNode dn, CompositeLocation constraint) {
664 VarDescriptor vd = dn.getVarDescriptor();
666 CompositeLocation destLoc = d2loc.get(vd);
668 if (dn.getExpression() != null) {
669 CompositeLocation expressionLoc =
670 checkLocationFromExpressionNode(md, nametable, dn.getExpression(),
671 new CompositeLocation(), constraint, false);
672 // addTypeLocation(dn.getExpression().getType(), expressionLoc);
674 if (expressionLoc != null) {
675 // checking location order
676 if (!CompositeLattice.isGreaterThan(expressionLoc, destLoc,
677 generateErrorMessage(md.getClassDesc(), dn))) {
678 throw new Error("The value flow from " + expressionLoc + " to " + destLoc
679 + " does not respect location hierarchy on the assignment " + dn.printNode(0)
680 + " at " + md.getClassDesc().getSourceFileName() + "::" + dn.getNumLine());
683 return expressionLoc;
687 return new CompositeLocation();
693 private void checkDeclarationInSubBlockNode(MethodDescriptor md, SymbolTable nametable,
695 checkDeclarationInBlockNode(md, nametable.getParent(), sbn.getBlockNode());
698 private CompositeLocation checkLocationFromBlockExpressionNode(MethodDescriptor md,
699 SymbolTable nametable, BlockExpressionNode ben, CompositeLocation constraint) {
700 CompositeLocation compLoc =
701 checkLocationFromExpressionNode(md, nametable, ben.getExpression(), null, constraint, false);
702 // addTypeLocation(ben.getExpression().getType(), compLoc);
706 private CompositeLocation checkLocationFromExpressionNode(MethodDescriptor md,
707 SymbolTable nametable, ExpressionNode en, CompositeLocation loc,
708 CompositeLocation constraint, boolean isLHS) {
710 CompositeLocation compLoc = null;
713 case Kind.AssignmentNode:
715 checkLocationFromAssignmentNode(md, nametable, (AssignmentNode) en, loc, constraint);
718 case Kind.FieldAccessNode:
720 checkLocationFromFieldAccessNode(md, nametable, (FieldAccessNode) en, loc, constraint);
724 compLoc = checkLocationFromNameNode(md, nametable, (NameNode) en, loc, constraint);
728 compLoc = checkLocationFromOpNode(md, nametable, (OpNode) en, constraint);
731 case Kind.CreateObjectNode:
732 compLoc = checkLocationFromCreateObjectNode(md, nametable, (CreateObjectNode) en);
735 case Kind.ArrayAccessNode:
737 checkLocationFromArrayAccessNode(md, nametable, (ArrayAccessNode) en, constraint, isLHS);
740 case Kind.LiteralNode:
741 compLoc = checkLocationFromLiteralNode(md, nametable, (LiteralNode) en, loc);
744 case Kind.MethodInvokeNode:
746 checkLocationFromMethodInvokeNode(md, nametable, (MethodInvokeNode) en, loc, constraint);
749 case Kind.TertiaryNode:
750 compLoc = checkLocationFromTertiaryNode(md, nametable, (TertiaryNode) en, constraint);
754 compLoc = checkLocationFromCastNode(md, nametable, (CastNode) en, constraint);
757 // case Kind.InstanceOfNode:
758 // checkInstanceOfNode(md, nametable, (InstanceOfNode) en, td);
761 // case Kind.ArrayInitializerNode:
762 // checkArrayInitializerNode(md, nametable, (ArrayInitializerNode) en,
766 // case Kind.ClassTypeNode:
767 // checkClassTypeNode(md, nametable, (ClassTypeNode) en, td);
770 // case Kind.OffsetNode:
771 // checkOffsetNode(md, nametable, (OffsetNode)en, td);
778 // addTypeLocation(en.getType(), compLoc);
783 private CompositeLocation checkLocationFromCastNode(MethodDescriptor md, SymbolTable nametable,
784 CastNode cn, CompositeLocation constraint) {
786 ExpressionNode en = cn.getExpression();
787 return checkLocationFromExpressionNode(md, nametable, en, new CompositeLocation(), constraint,
792 private CompositeLocation checkLocationFromTertiaryNode(MethodDescriptor md,
793 SymbolTable nametable, TertiaryNode tn, CompositeLocation constraint) {
794 ClassDescriptor cd = md.getClassDesc();
796 CompositeLocation condLoc =
797 checkLocationFromExpressionNode(md, nametable, tn.getCond(), new CompositeLocation(),
799 // addLocationType(tn.getCond().getType(), condLoc);
800 CompositeLocation trueLoc =
801 checkLocationFromExpressionNode(md, nametable, tn.getTrueExpr(), new CompositeLocation(),
803 // addLocationType(tn.getTrueExpr().getType(), trueLoc);
804 CompositeLocation falseLoc =
805 checkLocationFromExpressionNode(md, nametable, tn.getFalseExpr(), new CompositeLocation(),
807 // addLocationType(tn.getFalseExpr().getType(), falseLoc);
809 // locations from true/false branches can be TOP when there are only literal
811 // in this case, we don't need to check flow down rule!
813 // check if condLoc is higher than trueLoc & falseLoc
814 if (!trueLoc.get(0).isTop()
815 && !CompositeLattice.isGreaterThan(condLoc, trueLoc, generateErrorMessage(cd, tn))) {
817 "The location of the condition expression is lower than the true expression at "
818 + cd.getSourceFileName() + ":" + tn.getCond().getNumLine());
821 if (!falseLoc.get(0).isTop()
822 && !CompositeLattice.isGreaterThan(condLoc, falseLoc,
823 generateErrorMessage(cd, tn.getCond()))) {
825 "The location of the condition expression is lower than the true expression at "
826 + cd.getSourceFileName() + ":" + tn.getCond().getNumLine());
829 // then, return glb of trueLoc & falseLoc
830 Set<CompositeLocation> glbInputSet = new HashSet<CompositeLocation>();
831 glbInputSet.add(trueLoc);
832 glbInputSet.add(falseLoc);
834 return CompositeLattice.calculateGLB(glbInputSet, generateErrorMessage(cd, tn));
837 private CompositeLocation checkLocationFromMethodInvokeNode(MethodDescriptor md,
838 SymbolTable nametable, MethodInvokeNode min, CompositeLocation loc,
839 CompositeLocation constraint) {
841 ClassDescriptor cd = md.getClassDesc();
842 MethodDescriptor calleeMD = min.getMethod();
844 if (!ssjava.isTrustMethod(calleeMD)) {
845 CompositeLocation baseLocation = null;
846 if (min.getExpression() != null) {
848 checkLocationFromExpressionNode(md, nametable, min.getExpression(),
849 new CompositeLocation(), constraint, false);
852 if (min.getMethod().isStatic()) {
853 String globalLocId = ssjava.getMethodLattice(md).getGlobalLoc();
854 if (globalLocId == null) {
855 throw new Error("Method lattice does not define global variable location at "
856 + generateErrorMessage(md.getClassDesc(), min));
858 baseLocation = new CompositeLocation(new Location(md, globalLocId));
860 String thisLocId = ssjava.getMethodLattice(md).getThisLoc();
861 baseLocation = new CompositeLocation(new Location(md, thisLocId));
866 System.out.println("\n#checkLocationFromMethodInvokeNode=" + min.printNode(0)
867 + " baseLocation=" + baseLocation);
870 CompositeLattice.compare(constraint, baseLocation, true, generateErrorMessage(cd, min));
872 if (compareResult == ComparisonResult.LESS) {
873 throw new Error("Method invocation does not respect the current branch constraint at "
874 + generateErrorMessage(cd, min));
875 } else if (compareResult != ComparisonResult.GREATER) {
876 // if the current constraint is higher than method's THIS location
877 // no need to check constraints!
878 CompositeLocation calleeConstraint =
879 translateCallerLocToCalleeLoc(calleeMD, baseLocation, constraint);
880 checkMethodBody(calleeMD.getClassDesc(), calleeMD, calleeConstraint);
883 checkCalleeConstraints(md, nametable, min, baseLocation, constraint);
885 checkCallerArgumentLocationConstraints(md, nametable, min, baseLocation, constraint);
887 if (!min.getMethod().getReturnType().isVoid()) {
888 // If method has a return value, compute the highest possible return
889 // location in the caller's perspective
890 CompositeLocation ceilingLoc =
891 computeCeilingLocationForCaller(md, nametable, min, baseLocation, constraint);
896 return new CompositeLocation();
900 private CompositeLocation translateCallerLocToCalleeLoc(MethodDescriptor calleeMD,
901 CompositeLocation calleeBaseLoc, CompositeLocation constraint) {
903 CompositeLocation calleeConstraint = new CompositeLocation();
905 // if (constraint.startsWith(calleeBaseLoc)) {
906 // if the first part of constraint loc is matched with callee base loc
907 Location thisLoc = new Location(calleeMD, ssjava.getMethodLattice(calleeMD).getThisLoc());
908 calleeConstraint.addLocation(thisLoc);
909 for (int i = calleeBaseLoc.getSize(); i < constraint.getSize(); i++) {
910 calleeConstraint.addLocation(constraint.get(i));
915 return calleeConstraint;
918 private void checkCallerArgumentLocationConstraints(MethodDescriptor md, SymbolTable nametable,
919 MethodInvokeNode min, CompositeLocation callerBaseLoc, CompositeLocation constraint) {
920 // if parameter location consists of THIS and FIELD location,
921 // caller should pass an argument that is comparable to the declared
922 // parameter location
923 // and is not lower than the declared parameter location in the field
926 MethodDescriptor calleemd = min.getMethod();
928 List<CompositeLocation> callerArgList = new ArrayList<CompositeLocation>();
929 List<CompositeLocation> calleeParamList = new ArrayList<CompositeLocation>();
931 MethodLattice<String> calleeLattice = ssjava.getMethodLattice(calleemd);
932 Location calleeThisLoc = new Location(calleemd, calleeLattice.getThisLoc());
934 for (int i = 0; i < min.numArgs(); i++) {
935 ExpressionNode en = min.getArg(i);
936 CompositeLocation callerArgLoc =
937 checkLocationFromExpressionNode(md, nametable, en, new CompositeLocation(), constraint,
939 callerArgList.add(callerArgLoc);
942 // setup callee params set
943 for (int i = 0; i < calleemd.numParameters(); i++) {
944 VarDescriptor calleevd = (VarDescriptor) calleemd.getParameter(i);
945 CompositeLocation calleeLoc = d2loc.get(calleevd);
946 calleeParamList.add(calleeLoc);
949 String errorMsg = generateErrorMessage(md.getClassDesc(), min);
951 System.out.println("checkCallerArgumentLocationConstraints=" + min.printNode(0));
952 System.out.println("base location=" + callerBaseLoc);
954 for (int i = 0; i < calleeParamList.size(); i++) {
955 CompositeLocation calleeParamLoc = calleeParamList.get(i);
956 if (calleeParamLoc.get(0).equals(calleeThisLoc) && calleeParamLoc.getSize() > 1) {
958 // callee parameter location has field information
959 CompositeLocation callerArgLoc = callerArgList.get(i);
961 CompositeLocation paramLocation =
962 translateCalleeParamLocToCaller(md, calleeParamLoc, callerBaseLoc, errorMsg);
964 Set<CompositeLocation> inputGLBSet = new HashSet<CompositeLocation>();
965 if (constraint != null) {
966 inputGLBSet.add(callerArgLoc);
967 inputGLBSet.add(constraint);
969 CompositeLattice.calculateGLB(inputGLBSet,
970 generateErrorMessage(md.getClassDesc(), min));
973 if (!CompositeLattice.isGreaterThan(callerArgLoc, paramLocation, errorMsg)) {
974 throw new Error("Caller argument '" + min.getArg(i).printNode(0) + " : " + callerArgLoc
975 + "' should be higher than corresponding callee's parameter : " + paramLocation
976 + " at " + errorMsg);
984 private CompositeLocation translateCalleeParamLocToCaller(MethodDescriptor md,
985 CompositeLocation calleeParamLoc, CompositeLocation callerBaseLocation, String errorMsg) {
987 CompositeLocation translate = new CompositeLocation();
989 for (int i = 0; i < callerBaseLocation.getSize(); i++) {
990 translate.addLocation(callerBaseLocation.get(i));
993 for (int i = 1; i < calleeParamLoc.getSize(); i++) {
994 translate.addLocation(calleeParamLoc.get(i));
997 System.out.println("TRANSLATED=" + translate + " from calleeParamLoc=" + calleeParamLoc);
1002 private CompositeLocation computeCeilingLocationForCaller(MethodDescriptor md,
1003 SymbolTable nametable, MethodInvokeNode min, CompositeLocation baseLocation,
1004 CompositeLocation constraint) {
1005 List<CompositeLocation> argList = new ArrayList<CompositeLocation>();
1007 // by default, method has a THIS parameter
1008 argList.add(baseLocation);
1010 for (int i = 0; i < min.numArgs(); i++) {
1011 ExpressionNode en = min.getArg(i);
1012 CompositeLocation callerArg =
1013 checkLocationFromExpressionNode(md, nametable, en, new CompositeLocation(), constraint,
1015 argList.add(callerArg);
1018 System.out.println("\n## computeReturnLocation=" + min.getMethod() + " argList=" + argList);
1019 CompositeLocation ceilLoc = md2ReturnLocGen.get(min.getMethod()).computeReturnLocation(argList);
1020 System.out.println("## ReturnLocation=" + ceilLoc);
1026 private void checkCalleeConstraints(MethodDescriptor md, SymbolTable nametable,
1027 MethodInvokeNode min, CompositeLocation callerBaseLoc, CompositeLocation constraint) {
1029 System.out.println("checkCalleeConstraints=" + min.printNode(0));
1031 MethodDescriptor calleemd = min.getMethod();
1033 MethodLattice<String> calleeLattice = ssjava.getMethodLattice(calleemd);
1034 CompositeLocation calleeThisLoc =
1035 new CompositeLocation(new Location(calleemd, calleeLattice.getThisLoc()));
1037 List<CompositeLocation> callerArgList = new ArrayList<CompositeLocation>();
1038 List<CompositeLocation> calleeParamList = new ArrayList<CompositeLocation>();
1040 if (min.numArgs() > 0) {
1041 // caller needs to guarantee that it passes arguments in regarding to
1042 // callee's hierarchy
1044 // setup caller args set
1045 // first, add caller's base(this) location
1046 callerArgList.add(callerBaseLoc);
1047 // second, add caller's arguments
1048 for (int i = 0; i < min.numArgs(); i++) {
1049 ExpressionNode en = min.getArg(i);
1050 CompositeLocation callerArgLoc =
1051 checkLocationFromExpressionNode(md, nametable, en, new CompositeLocation(), constraint,
1053 callerArgList.add(callerArgLoc);
1056 // setup callee params set
1057 // first, add callee's this location
1058 calleeParamList.add(calleeThisLoc);
1059 // second, add callee's parameters
1060 for (int i = 0; i < calleemd.numParameters(); i++) {
1061 VarDescriptor calleevd = (VarDescriptor) calleemd.getParameter(i);
1062 CompositeLocation calleeLoc = d2loc.get(calleevd);
1063 System.out.println("calleevd=" + calleevd + " loc=" + calleeLoc);
1064 calleeParamList.add(calleeLoc);
1067 // here, check if ordering relations among caller's args respect
1068 // ordering relations in-between callee's args
1069 CHECK: for (int i = 0; i < calleeParamList.size(); i++) {
1070 CompositeLocation calleeLoc1 = calleeParamList.get(i);
1071 CompositeLocation callerLoc1 = callerArgList.get(i);
1073 for (int j = 0; j < calleeParamList.size(); j++) {
1075 CompositeLocation calleeLoc2 = calleeParamList.get(j);
1076 CompositeLocation callerLoc2 = callerArgList.get(j);
1078 if (callerLoc1.get(callerLoc1.getSize() - 1).isTop()
1079 || callerLoc2.get(callerLoc2.getSize() - 1).isTop()) {
1083 System.out.println("calleeLoc1=" + calleeLoc1);
1084 System.out.println("calleeLoc2=" + calleeLoc2 + "calleeParamList=" + calleeParamList);
1087 CompositeLattice.compare(callerLoc1, callerLoc2, true,
1088 generateErrorMessage(md.getClassDesc(), min));
1090 CompositeLattice.compare(calleeLoc1, calleeLoc2, true,
1091 generateErrorMessage(md.getClassDesc(), min));
1093 if (calleeResult == ComparisonResult.GREATER
1094 && callerResult != ComparisonResult.GREATER) {
1095 // If calleeLoc1 is higher than calleeLoc2
1096 // then, caller should have same ordering relation in-bet
1097 // callerLoc1 & callerLoc2
1099 String paramName1, paramName2;
1102 paramName1 = "'THIS'";
1104 paramName1 = "'parameter " + calleemd.getParamName(i - 1) + "'";
1108 paramName2 = "'THIS'";
1110 paramName2 = "'parameter " + calleemd.getParamName(j - 1) + "'";
1114 "Caller doesn't respect an ordering relation among method arguments: callee expects that "
1115 + paramName1 + " should be higher than " + paramName2 + " in " + calleemd
1116 + " at " + md.getClassDesc().getSourceFileName() + ":" + min.getNumLine());
1127 private CompositeLocation checkLocationFromArrayAccessNode(MethodDescriptor md,
1128 SymbolTable nametable, ArrayAccessNode aan, CompositeLocation constraint, boolean isLHS) {
1130 ClassDescriptor cd = md.getClassDesc();
1132 CompositeLocation arrayLoc =
1133 checkLocationFromExpressionNode(md, nametable, aan.getExpression(),
1134 new CompositeLocation(), constraint, isLHS);
1135 // addTypeLocation(aan.getExpression().getType(), arrayLoc);
1136 CompositeLocation indexLoc =
1137 checkLocationFromExpressionNode(md, nametable, aan.getIndex(), new CompositeLocation(),
1139 // addTypeLocation(aan.getIndex().getType(), indexLoc);
1142 if (!CompositeLattice.isGreaterThan(indexLoc, arrayLoc, generateErrorMessage(cd, aan))) {
1143 throw new Error("Array index value is not higher than array location at "
1144 + generateErrorMessage(cd, aan));
1148 Set<CompositeLocation> inputGLB = new HashSet<CompositeLocation>();
1149 inputGLB.add(arrayLoc);
1150 inputGLB.add(indexLoc);
1151 return CompositeLattice.calculateGLB(inputGLB, generateErrorMessage(cd, aan));
1156 private CompositeLocation checkLocationFromCreateObjectNode(MethodDescriptor md,
1157 SymbolTable nametable, CreateObjectNode con) {
1159 ClassDescriptor cd = md.getClassDesc();
1161 CompositeLocation compLoc = new CompositeLocation();
1162 compLoc.addLocation(Location.createTopLocation(md));
1167 private CompositeLocation checkLocationFromOpNode(MethodDescriptor md, SymbolTable nametable,
1168 OpNode on, CompositeLocation constraint) {
1170 ClassDescriptor cd = md.getClassDesc();
1171 CompositeLocation leftLoc = new CompositeLocation();
1173 checkLocationFromExpressionNode(md, nametable, on.getLeft(), leftLoc, constraint, false);
1174 // addTypeLocation(on.getLeft().getType(), leftLoc);
1176 CompositeLocation rightLoc = new CompositeLocation();
1177 if (on.getRight() != null) {
1179 checkLocationFromExpressionNode(md, nametable, on.getRight(), rightLoc, constraint, false);
1180 // addTypeLocation(on.getRight().getType(), rightLoc);
1183 System.out.println("\n# OP NODE=" + on.printNode(0));
1184 System.out.println("# left loc=" + leftLoc + " from " + on.getLeft().getClass());
1185 if (on.getRight() != null) {
1186 System.out.println("# right loc=" + rightLoc + " from " + on.getRight().getClass());
1189 Operation op = on.getOp();
1191 switch (op.getOp()) {
1193 case Operation.UNARYPLUS:
1194 case Operation.UNARYMINUS:
1195 case Operation.LOGIC_NOT:
1199 case Operation.LOGIC_OR:
1200 case Operation.LOGIC_AND:
1201 case Operation.COMP:
1202 case Operation.BIT_OR:
1203 case Operation.BIT_XOR:
1204 case Operation.BIT_AND:
1205 case Operation.ISAVAILABLE:
1206 case Operation.EQUAL:
1207 case Operation.NOTEQUAL:
1214 case Operation.MULT:
1217 case Operation.LEFTSHIFT:
1218 case Operation.RIGHTSHIFT:
1219 case Operation.URIGHTSHIFT:
1221 Set<CompositeLocation> inputSet = new HashSet<CompositeLocation>();
1222 inputSet.add(leftLoc);
1223 inputSet.add(rightLoc);
1224 CompositeLocation glbCompLoc =
1225 CompositeLattice.calculateGLB(inputSet, generateErrorMessage(cd, on));
1226 System.out.println("# glbCompLoc=" + glbCompLoc);
1230 throw new Error(op.toString());
1235 private CompositeLocation checkLocationFromLiteralNode(MethodDescriptor md,
1236 SymbolTable nametable, LiteralNode en, CompositeLocation loc) {
1238 // literal value has the top location so that value can be flowed into any
1240 Location literalLoc = Location.createTopLocation(md);
1241 loc.addLocation(literalLoc);
1246 private CompositeLocation checkLocationFromNameNode(MethodDescriptor md, SymbolTable nametable,
1247 NameNode nn, CompositeLocation loc, CompositeLocation constraint) {
1249 NameDescriptor nd = nn.getName();
1250 if (nd.getBase() != null) {
1252 checkLocationFromExpressionNode(md, nametable, nn.getExpression(), loc, constraint, false);
1254 String varname = nd.toString();
1255 if (varname.equals("this")) {
1257 MethodLattice<String> methodLattice = ssjava.getMethodLattice(md);
1258 String thisLocId = methodLattice.getThisLoc();
1259 if (thisLocId == null) {
1260 throw new Error("The location for 'this' is not defined at "
1261 + md.getClassDesc().getSourceFileName() + "::" + nn.getNumLine());
1263 Location locElement = new Location(md, thisLocId);
1264 loc.addLocation(locElement);
1269 Descriptor d = (Descriptor) nametable.get(varname);
1271 // CompositeLocation localLoc = null;
1272 if (d instanceof VarDescriptor) {
1273 VarDescriptor vd = (VarDescriptor) d;
1274 // localLoc = d2loc.get(vd);
1275 // the type of var descriptor has a composite location!
1276 loc = ((CompositeLocation) vd.getType().getExtension()).clone();
1277 } else if (d instanceof FieldDescriptor) {
1278 // the type of field descriptor has a location!
1279 FieldDescriptor fd = (FieldDescriptor) d;
1280 if (fd.isStatic()) {
1282 // if it is 'static final', the location has TOP since no one can
1284 loc.addLocation(Location.createTopLocation(md));
1287 // if 'static', the location has pre-assigned global loc
1288 MethodLattice<String> localLattice = ssjava.getMethodLattice(md);
1289 String globalLocId = localLattice.getGlobalLoc();
1290 if (globalLocId == null) {
1291 throw new Error("Global location element is not defined in the method " + md);
1293 Location globalLoc = new Location(md, globalLocId);
1295 loc.addLocation(globalLoc);
1298 // the location of field access starts from this, followed by field
1300 MethodLattice<String> localLattice = ssjava.getMethodLattice(md);
1301 Location thisLoc = new Location(md, localLattice.getThisLoc());
1302 loc.addLocation(thisLoc);
1305 Location fieldLoc = (Location) fd.getType().getExtension();
1306 loc.addLocation(fieldLoc);
1307 } else if (d == null) {
1308 // access static field
1309 ClassDescriptor cd = nn.getClassDesc();
1311 MethodLattice<String> localLattice = ssjava.getMethodLattice(md);
1312 String globalLocId = localLattice.getGlobalLoc();
1313 if (globalLocId == null) {
1314 throw new Error("Method lattice does not define global variable location at "
1315 + generateErrorMessage(md.getClassDesc(), nn));
1317 loc.addLocation(new Location(md, globalLocId));
1325 private CompositeLocation checkLocationFromFieldAccessNode(MethodDescriptor md,
1326 SymbolTable nametable, FieldAccessNode fan, CompositeLocation loc,
1327 CompositeLocation constraint) {
1329 ExpressionNode left = fan.getExpression();
1330 TypeDescriptor ltd = left.getType();
1332 FieldDescriptor fd = fan.getField();
1334 String varName = null;
1335 if (left.kind() == Kind.NameNode) {
1336 NameDescriptor nd = ((NameNode) left).getName();
1337 varName = nd.toString();
1340 if (ltd.isClassNameRef() || (varName != null && varName.equals("this"))) {
1341 // using a class name directly or access using this
1342 if (fd.isStatic() && fd.isFinal()) {
1343 loc.addLocation(Location.createTopLocation(md));
1348 loc = checkLocationFromExpressionNode(md, nametable, left, loc, constraint, false);
1349 System.out.println("### checkLocationFromFieldAccessNode=" + fan.printNode(0));
1350 System.out.println("### left=" + left.printNode(0));
1351 if (!left.getType().isPrimitive()) {
1352 Location fieldLoc = getFieldLocation(fd);
1353 loc.addLocation(fieldLoc);
1359 private Location getFieldLocation(FieldDescriptor fd) {
1361 System.out.println("### getFieldLocation=" + fd);
1362 System.out.println("### fd.getType().getExtension()=" + fd.getType().getExtension());
1364 Location fieldLoc = (Location) fd.getType().getExtension();
1366 // handle the case that method annotation checking skips checking field
1368 if (fieldLoc == null) {
1369 fieldLoc = checkFieldDeclaration(fd.getClassDescriptor(), fd);
1376 private CompositeLocation checkLocationFromAssignmentNode(MethodDescriptor md,
1377 SymbolTable nametable, AssignmentNode an, CompositeLocation loc, CompositeLocation constraint) {
1379 System.out.println("\n# ASSIGNMENTNODE=" + an.printNode(0));
1381 ClassDescriptor cd = md.getClassDesc();
1383 Set<CompositeLocation> inputGLBSet = new HashSet<CompositeLocation>();
1385 boolean postinc = true;
1386 if (an.getOperation().getBaseOp() == null
1387 || (an.getOperation().getBaseOp().getOp() != Operation.POSTINC && an.getOperation()
1388 .getBaseOp().getOp() != Operation.POSTDEC))
1391 // if LHS is array access node, need to check if array index is higher
1392 // than array itself
1393 CompositeLocation destLocation =
1394 checkLocationFromExpressionNode(md, nametable, an.getDest(), new CompositeLocation(),
1397 CompositeLocation rhsLocation;
1398 CompositeLocation srcLocation;
1402 checkLocationFromExpressionNode(md, nametable, an.getSrc(), new CompositeLocation(),
1405 srcLocation = rhsLocation;
1407 // if (!rhsLocation.get(rhsLocation.getSize() - 1).isTop()) {
1408 if (constraint != null) {
1409 inputGLBSet.add(rhsLocation);
1410 inputGLBSet.add(constraint);
1411 srcLocation = CompositeLattice.calculateGLB(inputGLBSet, generateErrorMessage(cd, an));
1415 System.out.println("dstLocation=" + destLocation);
1416 System.out.println("rhsLocation=" + rhsLocation);
1417 System.out.println("srcLocation=" + srcLocation);
1418 System.out.println("constraint=" + constraint);
1420 if (!CompositeLattice.isGreaterThan(srcLocation, destLocation, generateErrorMessage(cd, an))) {
1422 String context = "";
1423 if (constraint != null) {
1424 context = " and the current context constraint is " + constraint;
1427 throw new Error("The value flow from " + srcLocation + " to " + destLocation
1428 + " does not respect location hierarchy on the assignment " + an.printNode(0) + context
1429 + " at " + cd.getSourceFileName() + "::" + an.getNumLine());
1435 checkLocationFromExpressionNode(md, nametable, an.getDest(), new CompositeLocation(),
1438 if (constraint != null) {
1439 inputGLBSet.add(rhsLocation);
1440 inputGLBSet.add(constraint);
1441 srcLocation = CompositeLattice.calculateGLB(inputGLBSet, generateErrorMessage(cd, an));
1443 srcLocation = rhsLocation;
1446 System.out.println("srcLocation=" + srcLocation);
1447 System.out.println("rhsLocation=" + rhsLocation);
1448 System.out.println("constraint=" + constraint);
1450 if (!CompositeLattice.isGreaterThan(srcLocation, destLocation, generateErrorMessage(cd, an))) {
1452 if (srcLocation.equals(destLocation)) {
1453 throw new Error("Location " + srcLocation
1454 + " is not allowed to have the value flow that moves within the same location at '"
1455 + an.printNode(0) + "' of " + cd.getSourceFileName() + "::" + an.getNumLine());
1457 throw new Error("The value flow from " + srcLocation + " to " + destLocation
1458 + " does not respect location hierarchy on the assignment " + an.printNode(0)
1459 + " at " + cd.getSourceFileName() + "::" + an.getNumLine());
1466 return destLocation;
1469 private void assignLocationOfVarDescriptor(VarDescriptor vd, MethodDescriptor md,
1470 SymbolTable nametable, TreeNode n) {
1472 ClassDescriptor cd = md.getClassDesc();
1473 Vector<AnnotationDescriptor> annotationVec = vd.getType().getAnnotationMarkers();
1475 // currently enforce every variable to have corresponding location
1476 if (annotationVec.size() == 0) {
1477 throw new Error("Location is not assigned to variable '" + vd.getSymbol() + "' in the method '"
1478 + md + "' of the class " + cd.getSymbol() + " at " + generateErrorMessage(cd, n));
1481 if (annotationVec.size() > 1) { // variable can have at most one location
1482 throw new Error(vd.getSymbol() + " has more than one location.");
1485 AnnotationDescriptor ad = annotationVec.elementAt(0);
1487 if (ad.getType() == AnnotationDescriptor.SINGLE_ANNOTATION) {
1489 if (ad.getMarker().equals(SSJavaAnalysis.LOC)) {
1490 String locDec = ad.getValue(); // check if location is defined
1492 if (locDec.startsWith(SSJavaAnalysis.DELTA)) {
1493 DeltaLocation deltaLoc = parseDeltaDeclaration(md, n, locDec);
1494 d2loc.put(vd, deltaLoc);
1495 addLocationType(vd.getType(), deltaLoc);
1497 CompositeLocation compLoc = parseLocationDeclaration(md, n, locDec);
1499 Location lastElement = compLoc.get(compLoc.getSize() - 1);
1500 if (ssjava.isSharedLocation(lastElement)) {
1501 ssjava.mapSharedLocation2Descriptor(lastElement, vd);
1504 d2loc.put(vd, compLoc);
1505 addLocationType(vd.getType(), compLoc);
1513 private DeltaLocation parseDeltaDeclaration(MethodDescriptor md, TreeNode n, String locDec) {
1516 int dIdx = locDec.indexOf(SSJavaAnalysis.DELTA);
1519 int beginIdx = dIdx + 6;
1520 locDec = locDec.substring(beginIdx, locDec.length() - 1);
1521 dIdx = locDec.indexOf(SSJavaAnalysis.DELTA);
1524 CompositeLocation compLoc = parseLocationDeclaration(md, n, locDec);
1525 DeltaLocation deltaLoc = new DeltaLocation(compLoc, deltaCount);
1530 private Location parseFieldLocDeclaraton(String decl, String msg) throws Exception {
1532 int idx = decl.indexOf(".");
1534 String className = decl.substring(0, idx);
1535 String fieldName = decl.substring(idx + 1);
1537 className.replaceAll(" ", "");
1538 fieldName.replaceAll(" ", "");
1540 Descriptor d = state.getClassSymbolTable().get(className);
1543 System.out.println("state.getClassSymbolTable()=" + state.getClassSymbolTable());
1544 throw new Error("The class in the location declaration '" + decl + "' does not exist at "
1548 assert (d instanceof ClassDescriptor);
1549 SSJavaLattice<String> lattice = ssjava.getClassLattice((ClassDescriptor) d);
1550 if (!lattice.containsKey(fieldName)) {
1551 throw new Error("The location " + fieldName + " is not defined in the field lattice of '"
1552 + className + "' at " + msg);
1555 return new Location(d, fieldName);
1558 private CompositeLocation parseLocationDeclaration(MethodDescriptor md, TreeNode n, String locDec) {
1560 CompositeLocation compLoc = new CompositeLocation();
1562 StringTokenizer tokenizer = new StringTokenizer(locDec, ",");
1563 List<String> locIdList = new ArrayList<String>();
1564 while (tokenizer.hasMoreTokens()) {
1565 String locId = tokenizer.nextToken();
1566 locIdList.add(locId);
1569 // at least,one location element needs to be here!
1570 assert (locIdList.size() > 0);
1572 // assume that loc with idx 0 comes from the local lattice
1573 // loc with idx 1 comes from the field lattice
1575 String localLocId = locIdList.get(0);
1576 SSJavaLattice<String> localLattice = CompositeLattice.getLatticeByDescriptor(md);
1577 Location localLoc = new Location(md, localLocId);
1578 if (localLattice == null || (!localLattice.containsKey(localLocId))) {
1579 System.out.println("locDec=" + locDec);
1580 throw new Error("Location " + localLocId
1581 + " is not defined in the local variable lattice at "
1582 + md.getClassDesc().getSourceFileName() + "::" + (n != null ? n.getNumLine() : md) + ".");
1584 compLoc.addLocation(localLoc);
1586 for (int i = 1; i < locIdList.size(); i++) {
1587 String locName = locIdList.get(i);
1590 parseFieldLocDeclaraton(locName, generateErrorMessage(md.getClassDesc(), n));
1591 compLoc.addLocation(fieldLoc);
1592 } catch (Exception e) {
1593 throw new Error("The location declaration '" + locName + "' is wrong at "
1594 + generateErrorMessage(md.getClassDesc(), n));
1602 private void checkDeclarationNode(MethodDescriptor md, SymbolTable nametable, DeclarationNode dn) {
1603 VarDescriptor vd = dn.getVarDescriptor();
1604 assignLocationOfVarDescriptor(vd, md, nametable, dn);
1607 private void checkDeclarationInClass(ClassDescriptor cd) {
1608 // Check to see that fields are okay
1609 for (Iterator field_it = cd.getFields(); field_it.hasNext();) {
1610 FieldDescriptor fd = (FieldDescriptor) field_it.next();
1612 if (!(fd.isFinal() && fd.isStatic())) {
1613 checkFieldDeclaration(cd, fd);
1615 // for static final, assign top location by default
1616 Location loc = Location.createTopLocation(cd);
1617 addLocationType(fd.getType(), loc);
1622 private Location checkFieldDeclaration(ClassDescriptor cd, FieldDescriptor fd) {
1624 Vector<AnnotationDescriptor> annotationVec = fd.getType().getAnnotationMarkers();
1626 // currently enforce every field to have corresponding location
1627 if (annotationVec.size() == 0) {
1628 throw new Error("Location is not assigned to the field '" + fd.getSymbol()
1629 + "' of the class " + cd.getSymbol() + " at " + cd.getSourceFileName());
1632 if (annotationVec.size() > 1) {
1633 // variable can have at most one location
1634 throw new Error("Field " + fd.getSymbol() + " of class " + cd
1635 + " has more than one location.");
1638 AnnotationDescriptor ad = annotationVec.elementAt(0);
1639 Location loc = null;
1641 if (ad.getType() == AnnotationDescriptor.SINGLE_ANNOTATION) {
1642 if (ad.getMarker().equals(SSJavaAnalysis.LOC)) {
1643 String locationID = ad.getValue();
1644 // check if location is defined
1645 SSJavaLattice<String> lattice = ssjava.getClassLattice(cd);
1646 if (lattice == null || (!lattice.containsKey(locationID))) {
1647 throw new Error("Location " + locationID
1648 + " is not defined in the field lattice of class " + cd.getSymbol() + " at"
1649 + cd.getSourceFileName() + ".");
1651 loc = new Location(cd, locationID);
1653 if (ssjava.isSharedLocation(loc)) {
1654 ssjava.mapSharedLocation2Descriptor(loc, fd);
1657 addLocationType(fd.getType(), loc);
1665 private void addLocationType(TypeDescriptor type, CompositeLocation loc) {
1667 type.setExtension(loc);
1671 private void addLocationType(TypeDescriptor type, Location loc) {
1673 type.setExtension(loc);
1677 static class CompositeLattice {
1679 public static boolean isGreaterThan(CompositeLocation loc1, CompositeLocation loc2, String msg) {
1681 System.out.println("\nisGreaterThan=" + loc1 + " " + loc2 + " msg=" + msg);
1682 int baseCompareResult = compareBaseLocationSet(loc1, loc2, true, false, msg);
1683 if (baseCompareResult == ComparisonResult.EQUAL) {
1684 if (compareDelta(loc1, loc2) == ComparisonResult.GREATER) {
1689 } else if (baseCompareResult == ComparisonResult.GREATER) {
1697 public static int compare(CompositeLocation loc1, CompositeLocation loc2, boolean ignore,
1700 System.out.println("compare=" + loc1 + " " + loc2);
1701 int baseCompareResult = compareBaseLocationSet(loc1, loc2, false, ignore, msg);
1703 if (baseCompareResult == ComparisonResult.EQUAL) {
1704 return compareDelta(loc1, loc2);
1706 return baseCompareResult;
1711 private static int compareDelta(CompositeLocation dLoc1, CompositeLocation dLoc2) {
1713 int deltaCount1 = 0;
1714 int deltaCount2 = 0;
1715 if (dLoc1 instanceof DeltaLocation) {
1716 deltaCount1 = ((DeltaLocation) dLoc1).getNumDelta();
1719 if (dLoc2 instanceof DeltaLocation) {
1720 deltaCount2 = ((DeltaLocation) dLoc2).getNumDelta();
1722 if (deltaCount1 < deltaCount2) {
1723 return ComparisonResult.GREATER;
1724 } else if (deltaCount1 == deltaCount2) {
1725 return ComparisonResult.EQUAL;
1727 return ComparisonResult.LESS;
1732 private static int compareBaseLocationSet(CompositeLocation compLoc1,
1733 CompositeLocation compLoc2, boolean awareSharedLoc, boolean ignore, String msg) {
1735 // if compLoc1 is greater than compLoc2, return true
1736 // else return false;
1738 // compare one by one in according to the order of the tuple
1740 for (int i = 0; i < compLoc1.getSize(); i++) {
1741 Location loc1 = compLoc1.get(i);
1742 if (i >= compLoc2.getSize()) {
1744 return ComparisonResult.INCOMPARABLE;
1746 throw new Error("Failed to compare two locations of " + compLoc1 + " and " + compLoc2
1747 + " because they are not comparable at " + msg);
1750 Location loc2 = compLoc2.get(i);
1752 Descriptor descriptor = getCommonParentDescriptor(loc1, loc2, msg);
1753 SSJavaLattice<String> lattice = getLatticeByDescriptor(descriptor);
1755 // check if the shared location is appeared only at the end of the
1756 // composite location
1757 if (lattice.getSharedLocSet().contains(loc1.getLocIdentifier())) {
1758 if (i != (compLoc1.getSize() - 1)) {
1759 throw new Error("The shared location " + loc1.getLocIdentifier()
1760 + " cannot be appeared in the middle of composite location at" + msg);
1764 if (lattice.getSharedLocSet().contains(loc2.getLocIdentifier())) {
1765 if (i != (compLoc2.getSize() - 1)) {
1766 throw new Error("The shared location " + loc2.getLocIdentifier()
1767 + " cannot be appeared in the middle of composite location at " + msg);
1771 // if (!lattice1.equals(lattice2)) {
1772 // throw new Error("Failed to compare two locations of " + compLoc1 +
1773 // " and " + compLoc2
1774 // + " because they are not comparable at " + msg);
1777 if (loc1.getLocIdentifier().equals(loc2.getLocIdentifier())) {
1779 // check if the current location is the spinning location
1780 // note that the spinning location only can be appeared in the last
1781 // part of the composite location
1782 if (awareSharedLoc && numOfTie == compLoc1.getSize()
1783 && lattice.getSharedLocSet().contains(loc1.getLocIdentifier())) {
1784 return ComparisonResult.GREATER;
1787 } else if (lattice.isGreaterThan(loc1.getLocIdentifier(), loc2.getLocIdentifier())) {
1788 return ComparisonResult.GREATER;
1790 return ComparisonResult.LESS;
1795 if (numOfTie == compLoc1.getSize()) {
1797 if (numOfTie != compLoc2.getSize()) {
1800 return ComparisonResult.INCOMPARABLE;
1802 throw new Error("Failed to compare two locations of " + compLoc1 + " and " + compLoc2
1803 + " because they are not comparable at " + msg);
1808 return ComparisonResult.EQUAL;
1811 return ComparisonResult.LESS;
1815 public static CompositeLocation calculateGLB(Set<CompositeLocation> inputSet, String errMsg) {
1817 System.out.println("Calculating GLB=" + inputSet);
1818 CompositeLocation glbCompLoc = new CompositeLocation();
1820 // calculate GLB of the first(priority) element
1821 Set<String> priorityLocIdentifierSet = new HashSet<String>();
1822 Descriptor priorityDescriptor = null;
1824 Hashtable<String, Set<CompositeLocation>> locId2CompLocSet =
1825 new Hashtable<String, Set<CompositeLocation>>();
1826 // mapping from the priority loc ID to its full representation by the
1827 // composite location
1829 int maxTupleSize = 0;
1830 CompositeLocation maxCompLoc = null;
1832 Location prevPriorityLoc = null;
1833 for (Iterator iterator = inputSet.iterator(); iterator.hasNext();) {
1834 CompositeLocation compLoc = (CompositeLocation) iterator.next();
1835 if (compLoc.getSize() > maxTupleSize) {
1836 maxTupleSize = compLoc.getSize();
1837 maxCompLoc = compLoc;
1839 Location priorityLoc = compLoc.get(0);
1840 String priorityLocId = priorityLoc.getLocIdentifier();
1841 priorityLocIdentifierSet.add(priorityLocId);
1843 if (locId2CompLocSet.containsKey(priorityLocId)) {
1844 locId2CompLocSet.get(priorityLocId).add(compLoc);
1846 Set<CompositeLocation> newSet = new HashSet<CompositeLocation>();
1847 newSet.add(compLoc);
1848 locId2CompLocSet.put(priorityLocId, newSet);
1851 // check if priority location are coming from the same lattice
1852 if (priorityDescriptor == null) {
1853 priorityDescriptor = priorityLoc.getDescriptor();
1855 priorityDescriptor = getCommonParentDescriptor(priorityLoc, prevPriorityLoc, errMsg);
1857 prevPriorityLoc = priorityLoc;
1858 // else if (!priorityDescriptor.equals(priorityLoc.getDescriptor())) {
1859 // throw new Error("Failed to calculate GLB of " + inputSet
1860 // + " because they are from different lattices.");
1864 SSJavaLattice<String> locOrder = getLatticeByDescriptor(priorityDescriptor);
1865 String glbOfPriorityLoc = locOrder.getGLB(priorityLocIdentifierSet);
1867 glbCompLoc.addLocation(new Location(priorityDescriptor, glbOfPriorityLoc));
1868 Set<CompositeLocation> compSet = locId2CompLocSet.get(glbOfPriorityLoc);
1870 if (compSet == null) {
1871 // when GLB(x1,x2)!=x1 and !=x2 : GLB case 4
1872 // mean that the result is already lower than <x1,y1> and <x2,y2>
1873 // assign TOP to the rest of the location elements
1875 // in this case, do not take care about delta
1876 // CompositeLocation inputComp = inputSet.iterator().next();
1877 for (int i = 1; i < maxTupleSize; i++) {
1878 glbCompLoc.addLocation(Location.createTopLocation(maxCompLoc.get(i).getDescriptor()));
1882 // here find out composite location that has a maximum length tuple
1883 // if we have three input set: [A], [A,B], [A,B,C]
1884 // maximum length tuple will be [A,B,C]
1886 CompositeLocation maxFromCompSet = null;
1887 for (Iterator iterator = compSet.iterator(); iterator.hasNext();) {
1888 CompositeLocation c = (CompositeLocation) iterator.next();
1889 if (c.getSize() > max) {
1895 if (compSet.size() == 1) {
1896 // if GLB(x1,x2)==x1 or x2 : GLB case 2,3
1897 CompositeLocation comp = compSet.iterator().next();
1898 for (int i = 1; i < comp.getSize(); i++) {
1899 glbCompLoc.addLocation(comp.get(i));
1902 // if input location corresponding to glb is a delta, need to apply
1903 // delta to glb result
1904 if (comp instanceof DeltaLocation) {
1905 glbCompLoc = new DeltaLocation(glbCompLoc, 1);
1909 // when GLB(x1,x2)==x1 and x2 : GLB case 1
1910 // if more than one location shares the same priority GLB
1911 // need to calculate the rest of GLB loc
1913 // setup input set starting from the second tuple item
1914 Set<CompositeLocation> innerGLBInput = new HashSet<CompositeLocation>();
1915 for (Iterator iterator = compSet.iterator(); iterator.hasNext();) {
1916 CompositeLocation compLoc = (CompositeLocation) iterator.next();
1917 CompositeLocation innerCompLoc = new CompositeLocation();
1918 for (int idx = 1; idx < compLoc.getSize(); idx++) {
1919 innerCompLoc.addLocation(compLoc.get(idx));
1921 if (innerCompLoc.getSize() > 0) {
1922 innerGLBInput.add(innerCompLoc);
1926 if (innerGLBInput.size() > 0) {
1927 CompositeLocation innerGLB = CompositeLattice.calculateGLB(innerGLBInput, errMsg);
1928 for (int idx = 0; idx < innerGLB.getSize(); idx++) {
1929 glbCompLoc.addLocation(innerGLB.get(idx));
1933 // if input location corresponding to glb is a delta, need to apply
1934 // delta to glb result
1936 for (Iterator iterator = compSet.iterator(); iterator.hasNext();) {
1937 CompositeLocation compLoc = (CompositeLocation) iterator.next();
1938 if (compLoc instanceof DeltaLocation) {
1939 if (glbCompLoc.equals(compLoc)) {
1940 glbCompLoc = new DeltaLocation(glbCompLoc, 1);
1949 System.out.println("GLB=" + glbCompLoc);
1954 static SSJavaLattice<String> getLatticeByDescriptor(Descriptor d) {
1956 SSJavaLattice<String> lattice = null;
1958 if (d instanceof ClassDescriptor) {
1959 lattice = ssjava.getCd2lattice().get(d);
1960 } else if (d instanceof MethodDescriptor) {
1961 if (ssjava.getMd2lattice().containsKey(d)) {
1962 lattice = ssjava.getMd2lattice().get(d);
1964 // use default lattice for the method
1965 lattice = ssjava.getCd2methodDefault().get(((MethodDescriptor) d).getClassDesc());
1972 static Descriptor getCommonParentDescriptor(Location loc1, Location loc2, String msg) {
1974 Descriptor d1 = loc1.getDescriptor();
1975 Descriptor d2 = loc2.getDescriptor();
1977 Descriptor descriptor;
1979 if (d1 instanceof ClassDescriptor && d2 instanceof ClassDescriptor) {
1981 if (d1.equals(d2)) {
1984 // identifying which one is parent class
1985 Set<Descriptor> d1SubClassesSet = ssjava.tu.getSubClasses((ClassDescriptor) d1);
1986 Set<Descriptor> d2SubClassesSet = ssjava.tu.getSubClasses((ClassDescriptor) d2);
1988 if (d1 == null && d2 == null) {
1989 throw new Error("Failed to compare two locations of " + loc1 + " and " + loc2
1990 + " because they are not comparable at " + msg);
1991 } else if (d1SubClassesSet != null && d1SubClassesSet.contains(d2)) {
1993 } else if (d2SubClassesSet != null && d2SubClassesSet.contains(d1)) {
1996 throw new Error("Failed to compare two locations of " + loc1 + " and " + loc2
1997 + " because they are not comparable at " + msg);
2001 } else if (d1 instanceof MethodDescriptor && d2 instanceof MethodDescriptor) {
2003 if (d1.equals(d2)) {
2007 // identifying which one is parent class
2008 MethodDescriptor md1 = (MethodDescriptor) d1;
2009 MethodDescriptor md2 = (MethodDescriptor) d2;
2011 if (!md1.matches(md2)) {
2012 throw new Error("Failed to compare two locations of " + loc1 + " and " + loc2
2013 + " because they are not comparable at " + msg);
2016 Set<Descriptor> d1SubClassesSet =
2017 ssjava.tu.getSubClasses(((MethodDescriptor) d1).getClassDesc());
2018 Set<Descriptor> d2SubClassesSet =
2019 ssjava.tu.getSubClasses(((MethodDescriptor) d2).getClassDesc());
2021 if (d1 == null && d2 == null) {
2022 throw new Error("Failed to compare two locations of " + loc1 + " and " + loc2
2023 + " because they are not comparable at " + msg);
2024 } else if (d1 != null && d1SubClassesSet.contains(d2)) {
2026 } else if (d2 != null && d2SubClassesSet.contains(d1)) {
2029 throw new Error("Failed to compare two locations of " + loc1 + " and " + loc2
2030 + " because they are not comparable at " + msg);
2035 throw new Error("Failed to compare two locations of " + loc1 + " and " + loc2
2036 + " because they are not comparable at " + msg);
2045 class ComparisonResult {
2047 public static final int GREATER = 0;
2048 public static final int EQUAL = 1;
2049 public static final int LESS = 2;
2050 public static final int INCOMPARABLE = 3;
2057 class ReturnLocGenerator {
2059 public static final int PARAMISHIGHER = 0;
2060 public static final int PARAMISSAME = 1;
2061 public static final int IGNORE = 2;
2063 private Hashtable<Integer, Integer> paramIdx2paramType;
2065 private CompositeLocation declaredReturnLoc = null;
2067 public ReturnLocGenerator(CompositeLocation returnLoc, MethodDescriptor md,
2068 List<CompositeLocation> params, String msg) {
2070 CompositeLocation thisLoc = params.get(0);
2071 if (returnLoc.get(0).equals(thisLoc.get(0)) && returnLoc.getSize() > 1) {
2072 // if the declared return location consists of THIS and field location,
2073 // return location for the caller's side has to have same field element
2074 this.declaredReturnLoc = returnLoc;
2076 // creating mappings
2077 paramIdx2paramType = new Hashtable<Integer, Integer>();
2078 for (int i = 0; i < params.size(); i++) {
2079 CompositeLocation param = params.get(i);
2080 int compareResult = CompositeLattice.compare(param, returnLoc, true, msg);
2083 if (compareResult == ComparisonResult.GREATER) {
2085 } else if (compareResult == ComparisonResult.EQUAL) {
2090 paramIdx2paramType.put(new Integer(i), new Integer(type));
2096 public CompositeLocation computeReturnLocation(List<CompositeLocation> args) {
2098 if (declaredReturnLoc != null) {
2099 // when developer specify that the return value is [THIS,field]
2100 // needs to translate to the caller's location
2101 CompositeLocation callerLoc = new CompositeLocation();
2102 CompositeLocation callerBaseLocation = args.get(0);
2104 for (int i = 0; i < callerBaseLocation.getSize(); i++) {
2105 callerLoc.addLocation(callerBaseLocation.get(i));
2107 for (int i = 1; i < declaredReturnLoc.getSize(); i++) {
2108 callerLoc.addLocation(declaredReturnLoc.get(i));
2112 // compute the highest possible location in caller's side
2113 assert paramIdx2paramType.keySet().size() == args.size();
2115 Set<CompositeLocation> inputGLB = new HashSet<CompositeLocation>();
2116 for (int i = 0; i < args.size(); i++) {
2117 int type = (paramIdx2paramType.get(new Integer(i))).intValue();
2118 CompositeLocation argLoc = args.get(i);
2119 if (type == PARAMISHIGHER || type == PARAMISSAME) {
2120 // return loc is equal to or lower than param
2121 inputGLB.add(argLoc);
2125 // compute GLB of arguments subset that are same or higher than return
2127 CompositeLocation glb = CompositeLattice.calculateGLB(inputGLB, "");