1 //== RangeConstraintManager.cpp - Manage range constraints.------*- C++ -*--==//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file defines RangeConstraintManager, a class that tracks simple
11 // equality and inequality constraints on symbolic values of ProgramState.
13 //===----------------------------------------------------------------------===//
15 #include "RangedConstraintManager.h"
16 #include "clang/StaticAnalyzer/Core/PathSensitive/APSIntType.h"
17 #include "clang/StaticAnalyzer/Core/PathSensitive/ProgramState.h"
18 #include "clang/StaticAnalyzer/Core/PathSensitive/ProgramStateTrait.h"
19 #include "llvm/ADT/FoldingSet.h"
20 #include "llvm/ADT/ImmutableSet.h"
21 #include "llvm/Support/raw_ostream.h"
23 using namespace clang;
26 /// A Range represents the closed range [from, to]. The caller must
27 /// guarantee that from <= to. Note that Range is immutable, so as not
28 /// to subvert RangeSet's immutability.
30 class Range : public std::pair<const llvm::APSInt *, const llvm::APSInt *> {
32 Range(const llvm::APSInt &from, const llvm::APSInt &to)
33 : std::pair<const llvm::APSInt *, const llvm::APSInt *>(&from, &to) {
36 bool Includes(const llvm::APSInt &v) const {
37 return *first <= v && v <= *second;
39 const llvm::APSInt &From() const { return *first; }
40 const llvm::APSInt &To() const { return *second; }
41 const llvm::APSInt *getConcreteValue() const {
42 return &From() == &To() ? &From() : nullptr;
45 void Profile(llvm::FoldingSetNodeID &ID) const {
46 ID.AddPointer(&From());
51 class RangeTrait : public llvm::ImutContainerInfo<Range> {
53 // When comparing if one Range is less than another, we should compare
54 // the actual APSInt values instead of their pointers. This keeps the order
55 // consistent (instead of comparing by pointer values) and can potentially
56 // be used to speed up some of the operations in RangeSet.
57 static inline bool isLess(key_type_ref lhs, key_type_ref rhs) {
58 return *lhs.first < *rhs.first ||
59 (!(*rhs.first < *lhs.first) && *lhs.second < *rhs.second);
63 /// RangeSet contains a set of ranges. If the set is empty, then
64 /// there the value of a symbol is overly constrained and there are no
65 /// possible values for that symbol.
67 typedef llvm::ImmutableSet<Range, RangeTrait> PrimRangeSet;
68 PrimRangeSet ranges; // no need to make const, since it is an
69 // ImmutableSet - this allows default operator=
72 typedef PrimRangeSet::Factory Factory;
73 typedef PrimRangeSet::iterator iterator;
75 RangeSet(PrimRangeSet RS) : ranges(RS) {}
77 /// Create a new set with all ranges of this set and RS.
78 /// Possible intersections are not checked here.
79 RangeSet addRange(Factory &F, const RangeSet &RS) {
80 PrimRangeSet Ranges(RS.ranges);
81 for (const auto &range : ranges)
82 Ranges = F.add(Ranges, range);
83 return RangeSet(Ranges);
86 iterator begin() const { return ranges.begin(); }
87 iterator end() const { return ranges.end(); }
89 bool isEmpty() const { return ranges.isEmpty(); }
91 /// Construct a new RangeSet representing '{ [from, to] }'.
92 RangeSet(Factory &F, const llvm::APSInt &from, const llvm::APSInt &to)
93 : ranges(F.add(F.getEmptySet(), Range(from, to))) {}
95 /// Profile - Generates a hash profile of this RangeSet for use
97 void Profile(llvm::FoldingSetNodeID &ID) const { ranges.Profile(ID); }
99 /// getConcreteValue - If a symbol is contrained to equal a specific integer
100 /// constant then this method returns that value. Otherwise, it returns
102 const llvm::APSInt *getConcreteValue() const {
103 return ranges.isSingleton() ? ranges.begin()->getConcreteValue() : nullptr;
107 void IntersectInRange(BasicValueFactory &BV, Factory &F,
108 const llvm::APSInt &Lower, const llvm::APSInt &Upper,
109 PrimRangeSet &newRanges, PrimRangeSet::iterator &i,
110 PrimRangeSet::iterator &e) const {
111 // There are six cases for each range R in the set:
112 // 1. R is entirely before the intersection range.
113 // 2. R is entirely after the intersection range.
114 // 3. R contains the entire intersection range.
115 // 4. R starts before the intersection range and ends in the middle.
116 // 5. R starts in the middle of the intersection range and ends after it.
117 // 6. R is entirely contained in the intersection range.
118 // These correspond to each of the conditions below.
119 for (/* i = begin(), e = end() */; i != e; ++i) {
120 if (i->To() < Lower) {
123 if (i->From() > Upper) {
127 if (i->Includes(Lower)) {
128 if (i->Includes(Upper)) {
130 F.add(newRanges, Range(BV.getValue(Lower), BV.getValue(Upper)));
133 newRanges = F.add(newRanges, Range(BV.getValue(Lower), i->To()));
135 if (i->Includes(Upper)) {
136 newRanges = F.add(newRanges, Range(i->From(), BV.getValue(Upper)));
139 newRanges = F.add(newRanges, *i);
144 const llvm::APSInt &getMinValue() const {
146 return ranges.begin()->From();
149 bool pin(llvm::APSInt &Lower, llvm::APSInt &Upper) const {
150 // This function has nine cases, the cartesian product of range-testing
151 // both the upper and lower bounds against the symbol's type.
152 // Each case requires a different pinning operation.
153 // The function returns false if the described range is entirely outside
154 // the range of values for the associated symbol.
155 APSIntType Type(getMinValue());
156 APSIntType::RangeTestResultKind LowerTest = Type.testInRange(Lower, true);
157 APSIntType::RangeTestResultKind UpperTest = Type.testInRange(Upper, true);
160 case APSIntType::RTR_Below:
162 case APSIntType::RTR_Below:
163 // The entire range is outside the symbol's set of possible values.
164 // If this is a conventionally-ordered range, the state is infeasible.
168 // However, if the range wraps around, it spans all possible values.
169 Lower = Type.getMinValue();
170 Upper = Type.getMaxValue();
172 case APSIntType::RTR_Within:
173 // The range starts below what's possible but ends within it. Pin.
174 Lower = Type.getMinValue();
177 case APSIntType::RTR_Above:
178 // The range spans all possible values for the symbol. Pin.
179 Lower = Type.getMinValue();
180 Upper = Type.getMaxValue();
184 case APSIntType::RTR_Within:
186 case APSIntType::RTR_Below:
187 // The range wraps around, but all lower values are not possible.
189 Upper = Type.getMaxValue();
191 case APSIntType::RTR_Within:
192 // The range may or may not wrap around, but both limits are valid.
196 case APSIntType::RTR_Above:
197 // The range starts within what's possible but ends above it. Pin.
199 Upper = Type.getMaxValue();
203 case APSIntType::RTR_Above:
205 case APSIntType::RTR_Below:
206 // The range wraps but is outside the symbol's set of possible values.
208 case APSIntType::RTR_Within:
209 // The range starts above what's possible but ends within it (wrap).
210 Lower = Type.getMinValue();
213 case APSIntType::RTR_Above:
214 // The entire range is outside the symbol's set of possible values.
215 // If this is a conventionally-ordered range, the state is infeasible.
219 // However, if the range wraps around, it spans all possible values.
220 Lower = Type.getMinValue();
221 Upper = Type.getMaxValue();
231 // Returns a set containing the values in the receiving set, intersected with
232 // the closed range [Lower, Upper]. Unlike the Range type, this range uses
233 // modular arithmetic, corresponding to the common treatment of C integer
234 // overflow. Thus, if the Lower bound is greater than the Upper bound, the
235 // range is taken to wrap around. This is equivalent to taking the
236 // intersection with the two ranges [Min, Upper] and [Lower, Max],
237 // or, alternatively, /removing/ all integers between Upper and Lower.
238 RangeSet Intersect(BasicValueFactory &BV, Factory &F, llvm::APSInt Lower,
239 llvm::APSInt Upper) const {
240 if (!pin(Lower, Upper))
241 return F.getEmptySet();
243 PrimRangeSet newRanges = F.getEmptySet();
245 PrimRangeSet::iterator i = begin(), e = end();
247 IntersectInRange(BV, F, Lower, Upper, newRanges, i, e);
249 // The order of the next two statements is important!
250 // IntersectInRange() does not reset the iteration state for i and e.
251 // Therefore, the lower range most be handled first.
252 IntersectInRange(BV, F, BV.getMinValue(Upper), Upper, newRanges, i, e);
253 IntersectInRange(BV, F, Lower, BV.getMaxValue(Lower), newRanges, i, e);
259 void print(raw_ostream &os) const {
262 for (iterator i = begin(), e = end(); i != e; ++i) {
268 os << '[' << i->From().toString(10) << ", " << i->To().toString(10)
274 bool operator==(const RangeSet &other) const {
275 return ranges == other.ranges;
278 } // end anonymous namespace
280 REGISTER_TRAIT_WITH_PROGRAMSTATE(ConstraintRange,
281 CLANG_ENTO_PROGRAMSTATE_MAP(SymbolRef,
285 class RangeConstraintManager : public RangedConstraintManager {
287 RangeConstraintManager(SubEngine *SE, SValBuilder &SVB)
288 : RangedConstraintManager(SE, SVB) {}
290 //===------------------------------------------------------------------===//
291 // Implementation for interface from ConstraintManager.
292 //===------------------------------------------------------------------===//
294 bool canReasonAbout(SVal X) const override;
296 ConditionTruthVal checkNull(ProgramStateRef State, SymbolRef Sym) override;
298 const llvm::APSInt *getSymVal(ProgramStateRef State,
299 SymbolRef Sym) const override;
301 ProgramStateRef removeDeadBindings(ProgramStateRef State,
302 SymbolReaper &SymReaper) override;
304 void print(ProgramStateRef State, raw_ostream &Out, const char *nl,
305 const char *sep) override;
307 //===------------------------------------------------------------------===//
308 // Implementation for interface from RangedConstraintManager.
309 //===------------------------------------------------------------------===//
311 ProgramStateRef assumeSymNE(ProgramStateRef State, SymbolRef Sym,
312 const llvm::APSInt &V,
313 const llvm::APSInt &Adjustment) override;
315 ProgramStateRef assumeSymEQ(ProgramStateRef State, SymbolRef Sym,
316 const llvm::APSInt &V,
317 const llvm::APSInt &Adjustment) override;
319 ProgramStateRef assumeSymLT(ProgramStateRef State, SymbolRef Sym,
320 const llvm::APSInt &V,
321 const llvm::APSInt &Adjustment) override;
323 ProgramStateRef assumeSymGT(ProgramStateRef State, SymbolRef Sym,
324 const llvm::APSInt &V,
325 const llvm::APSInt &Adjustment) override;
327 ProgramStateRef assumeSymLE(ProgramStateRef State, SymbolRef Sym,
328 const llvm::APSInt &V,
329 const llvm::APSInt &Adjustment) override;
331 ProgramStateRef assumeSymGE(ProgramStateRef State, SymbolRef Sym,
332 const llvm::APSInt &V,
333 const llvm::APSInt &Adjustment) override;
335 ProgramStateRef assumeSymWithinInclusiveRange(
336 ProgramStateRef State, SymbolRef Sym, const llvm::APSInt &From,
337 const llvm::APSInt &To, const llvm::APSInt &Adjustment) override;
339 ProgramStateRef assumeSymOutsideInclusiveRange(
340 ProgramStateRef State, SymbolRef Sym, const llvm::APSInt &From,
341 const llvm::APSInt &To, const llvm::APSInt &Adjustment) override;
346 RangeSet getRange(ProgramStateRef State, SymbolRef Sym);
348 RangeSet getSymLTRange(ProgramStateRef St, SymbolRef Sym,
349 const llvm::APSInt &Int,
350 const llvm::APSInt &Adjustment);
351 RangeSet getSymGTRange(ProgramStateRef St, SymbolRef Sym,
352 const llvm::APSInt &Int,
353 const llvm::APSInt &Adjustment);
354 RangeSet getSymLERange(ProgramStateRef St, SymbolRef Sym,
355 const llvm::APSInt &Int,
356 const llvm::APSInt &Adjustment);
357 RangeSet getSymLERange(llvm::function_ref<RangeSet()> RS,
358 const llvm::APSInt &Int,
359 const llvm::APSInt &Adjustment);
360 RangeSet getSymGERange(ProgramStateRef St, SymbolRef Sym,
361 const llvm::APSInt &Int,
362 const llvm::APSInt &Adjustment);
365 } // end anonymous namespace
367 std::unique_ptr<ConstraintManager>
368 ento::CreateRangeConstraintManager(ProgramStateManager &StMgr, SubEngine *Eng) {
369 return llvm::make_unique<RangeConstraintManager>(Eng, StMgr.getSValBuilder());
372 bool RangeConstraintManager::canReasonAbout(SVal X) const {
373 Optional<nonloc::SymbolVal> SymVal = X.getAs<nonloc::SymbolVal>();
374 if (SymVal && SymVal->isExpression()) {
375 const SymExpr *SE = SymVal->getSymbol();
377 if (const SymIntExpr *SIE = dyn_cast<SymIntExpr>(SE)) {
378 switch (SIE->getOpcode()) {
379 // We don't reason yet about bitwise-constraints on symbolic values.
384 // We don't reason yet about these arithmetic constraints on
398 if (const SymSymExpr *SSE = dyn_cast<SymSymExpr>(SE)) {
399 // FIXME: Handle <=> here.
400 if (BinaryOperator::isEqualityOp(SSE->getOpcode()) ||
401 BinaryOperator::isRelationalOp(SSE->getOpcode())) {
402 // We handle Loc <> Loc comparisons, but not (yet) NonLoc <> NonLoc.
403 if (Loc::isLocType(SSE->getLHS()->getType())) {
404 assert(Loc::isLocType(SSE->getRHS()->getType()));
416 ConditionTruthVal RangeConstraintManager::checkNull(ProgramStateRef State,
418 const RangeSet *Ranges = State->get<ConstraintRange>(Sym);
420 // If we don't have any information about this symbol, it's underconstrained.
422 return ConditionTruthVal();
424 // If we have a concrete value, see if it's zero.
425 if (const llvm::APSInt *Value = Ranges->getConcreteValue())
428 BasicValueFactory &BV = getBasicVals();
429 APSIntType IntType = BV.getAPSIntType(Sym->getType());
430 llvm::APSInt Zero = IntType.getZeroValue();
432 // Check if zero is in the set of possible values.
433 if (Ranges->Intersect(BV, F, Zero, Zero).isEmpty())
436 // Zero is a possible value, but it is not the /only/ possible value.
437 return ConditionTruthVal();
440 const llvm::APSInt *RangeConstraintManager::getSymVal(ProgramStateRef St,
441 SymbolRef Sym) const {
442 const ConstraintRangeTy::data_type *T = St->get<ConstraintRange>(Sym);
443 return T ? T->getConcreteValue() : nullptr;
446 /// Scan all symbols referenced by the constraints. If the symbol is not alive
447 /// as marked in LSymbols, mark it as dead in DSymbols.
449 RangeConstraintManager::removeDeadBindings(ProgramStateRef State,
450 SymbolReaper &SymReaper) {
451 bool Changed = false;
452 ConstraintRangeTy CR = State->get<ConstraintRange>();
453 ConstraintRangeTy::Factory &CRFactory = State->get_context<ConstraintRange>();
455 for (ConstraintRangeTy::iterator I = CR.begin(), E = CR.end(); I != E; ++I) {
456 SymbolRef Sym = I.getKey();
457 if (SymReaper.maybeDead(Sym)) {
459 CR = CRFactory.remove(CR, Sym);
463 return Changed ? State->set<ConstraintRange>(CR) : State;
466 /// Return a range set subtracting zero from \p Domain.
467 static RangeSet assumeNonZero(
468 BasicValueFactory &BV,
469 RangeSet::Factory &F,
472 APSIntType IntType = BV.getAPSIntType(Sym->getType());
473 return Domain.Intersect(BV, F, ++IntType.getZeroValue(),
474 --IntType.getZeroValue());
477 /// \brief Apply implicit constraints for bitwise OR- and AND-.
478 /// For unsigned types, bitwise OR with a constant always returns
479 /// a value greater-or-equal than the constant, and bitwise AND
480 /// returns a value less-or-equal then the constant.
482 /// Pattern matches the expression \p Sym against those rule,
483 /// and applies the required constraints.
484 /// \p Input Previously established expression range set
485 static RangeSet applyBitwiseConstraints(
486 BasicValueFactory &BV,
487 RangeSet::Factory &F,
489 const SymIntExpr* SIE) {
490 QualType T = SIE->getType();
491 bool IsUnsigned = T->isUnsignedIntegerType();
492 const llvm::APSInt &RHS = SIE->getRHS();
493 const llvm::APSInt &Zero = BV.getAPSIntType(T).getZeroValue();
494 BinaryOperator::Opcode Operator = SIE->getOpcode();
496 // For unsigned types, the output of bitwise-or is bigger-or-equal than RHS.
497 if (Operator == BO_Or && IsUnsigned)
498 return Input.Intersect(BV, F, RHS, BV.getMaxValue(T));
500 // Bitwise-or with a non-zero constant is always non-zero.
501 if (Operator == BO_Or && RHS != Zero)
502 return assumeNonZero(BV, F, SIE, Input);
504 // For unsigned types, or positive RHS,
505 // bitwise-and output is always smaller-or-equal than RHS (assuming two's
506 // complement representation of signed types).
507 if (Operator == BO_And && (IsUnsigned || RHS >= Zero))
508 return Input.Intersect(BV, F, BV.getMinValue(T), RHS);
513 RangeSet RangeConstraintManager::getRange(ProgramStateRef State,
515 if (ConstraintRangeTy::data_type *V = State->get<ConstraintRange>(Sym))
518 // Lazily generate a new RangeSet representing all possible values for the
519 // given symbol type.
520 BasicValueFactory &BV = getBasicVals();
521 QualType T = Sym->getType();
523 RangeSet Result(F, BV.getMinValue(T), BV.getMaxValue(T));
525 // References are known to be non-zero.
526 if (T->isReferenceType())
527 return assumeNonZero(BV, F, Sym, Result);
529 // Known constraints on ranges of bitwise expressions.
530 if (const SymIntExpr* SIE = dyn_cast<SymIntExpr>(Sym))
531 return applyBitwiseConstraints(BV, F, Result, SIE);
536 //===------------------------------------------------------------------------===
537 // assumeSymX methods: protected interface for RangeConstraintManager.
538 //===------------------------------------------------------------------------===/
540 // The syntax for ranges below is mathematical, using [x, y] for closed ranges
541 // and (x, y) for open ranges. These ranges are modular, corresponding with
542 // a common treatment of C integer overflow. This means that these methods
543 // do not have to worry about overflow; RangeSet::Intersect can handle such a
544 // "wraparound" range.
545 // As an example, the range [UINT_MAX-1, 3) contains five values: UINT_MAX-1,
546 // UINT_MAX, 0, 1, and 2.
549 RangeConstraintManager::assumeSymNE(ProgramStateRef St, SymbolRef Sym,
550 const llvm::APSInt &Int,
551 const llvm::APSInt &Adjustment) {
552 // Before we do any real work, see if the value can even show up.
553 APSIntType AdjustmentType(Adjustment);
554 if (AdjustmentType.testInRange(Int, true) != APSIntType::RTR_Within)
557 llvm::APSInt Lower = AdjustmentType.convert(Int) - Adjustment;
558 llvm::APSInt Upper = Lower;
562 // [Int-Adjustment+1, Int-Adjustment-1]
563 // Notice that the lower bound is greater than the upper bound.
564 RangeSet New = getRange(St, Sym).Intersect(getBasicVals(), F, Upper, Lower);
565 return New.isEmpty() ? nullptr : St->set<ConstraintRange>(Sym, New);
569 RangeConstraintManager::assumeSymEQ(ProgramStateRef St, SymbolRef Sym,
570 const llvm::APSInt &Int,
571 const llvm::APSInt &Adjustment) {
572 // Before we do any real work, see if the value can even show up.
573 APSIntType AdjustmentType(Adjustment);
574 if (AdjustmentType.testInRange(Int, true) != APSIntType::RTR_Within)
577 // [Int-Adjustment, Int-Adjustment]
578 llvm::APSInt AdjInt = AdjustmentType.convert(Int) - Adjustment;
579 RangeSet New = getRange(St, Sym).Intersect(getBasicVals(), F, AdjInt, AdjInt);
580 return New.isEmpty() ? nullptr : St->set<ConstraintRange>(Sym, New);
583 RangeSet RangeConstraintManager::getSymLTRange(ProgramStateRef St,
585 const llvm::APSInt &Int,
586 const llvm::APSInt &Adjustment) {
587 // Before we do any real work, see if the value can even show up.
588 APSIntType AdjustmentType(Adjustment);
589 switch (AdjustmentType.testInRange(Int, true)) {
590 case APSIntType::RTR_Below:
591 return F.getEmptySet();
592 case APSIntType::RTR_Within:
594 case APSIntType::RTR_Above:
595 return getRange(St, Sym);
598 // Special case for Int == Min. This is always false.
599 llvm::APSInt ComparisonVal = AdjustmentType.convert(Int);
600 llvm::APSInt Min = AdjustmentType.getMinValue();
601 if (ComparisonVal == Min)
602 return F.getEmptySet();
604 llvm::APSInt Lower = Min - Adjustment;
605 llvm::APSInt Upper = ComparisonVal - Adjustment;
608 return getRange(St, Sym).Intersect(getBasicVals(), F, Lower, Upper);
612 RangeConstraintManager::assumeSymLT(ProgramStateRef St, SymbolRef Sym,
613 const llvm::APSInt &Int,
614 const llvm::APSInt &Adjustment) {
615 RangeSet New = getSymLTRange(St, Sym, Int, Adjustment);
616 return New.isEmpty() ? nullptr : St->set<ConstraintRange>(Sym, New);
619 RangeSet RangeConstraintManager::getSymGTRange(ProgramStateRef St,
621 const llvm::APSInt &Int,
622 const llvm::APSInt &Adjustment) {
623 // Before we do any real work, see if the value can even show up.
624 APSIntType AdjustmentType(Adjustment);
625 switch (AdjustmentType.testInRange(Int, true)) {
626 case APSIntType::RTR_Below:
627 return getRange(St, Sym);
628 case APSIntType::RTR_Within:
630 case APSIntType::RTR_Above:
631 return F.getEmptySet();
634 // Special case for Int == Max. This is always false.
635 llvm::APSInt ComparisonVal = AdjustmentType.convert(Int);
636 llvm::APSInt Max = AdjustmentType.getMaxValue();
637 if (ComparisonVal == Max)
638 return F.getEmptySet();
640 llvm::APSInt Lower = ComparisonVal - Adjustment;
641 llvm::APSInt Upper = Max - Adjustment;
644 return getRange(St, Sym).Intersect(getBasicVals(), F, Lower, Upper);
648 RangeConstraintManager::assumeSymGT(ProgramStateRef St, SymbolRef Sym,
649 const llvm::APSInt &Int,
650 const llvm::APSInt &Adjustment) {
651 RangeSet New = getSymGTRange(St, Sym, Int, Adjustment);
652 return New.isEmpty() ? nullptr : St->set<ConstraintRange>(Sym, New);
655 RangeSet RangeConstraintManager::getSymGERange(ProgramStateRef St,
657 const llvm::APSInt &Int,
658 const llvm::APSInt &Adjustment) {
659 // Before we do any real work, see if the value can even show up.
660 APSIntType AdjustmentType(Adjustment);
661 switch (AdjustmentType.testInRange(Int, true)) {
662 case APSIntType::RTR_Below:
663 return getRange(St, Sym);
664 case APSIntType::RTR_Within:
666 case APSIntType::RTR_Above:
667 return F.getEmptySet();
670 // Special case for Int == Min. This is always feasible.
671 llvm::APSInt ComparisonVal = AdjustmentType.convert(Int);
672 llvm::APSInt Min = AdjustmentType.getMinValue();
673 if (ComparisonVal == Min)
674 return getRange(St, Sym);
676 llvm::APSInt Max = AdjustmentType.getMaxValue();
677 llvm::APSInt Lower = ComparisonVal - Adjustment;
678 llvm::APSInt Upper = Max - Adjustment;
680 return getRange(St, Sym).Intersect(getBasicVals(), F, Lower, Upper);
684 RangeConstraintManager::assumeSymGE(ProgramStateRef St, SymbolRef Sym,
685 const llvm::APSInt &Int,
686 const llvm::APSInt &Adjustment) {
687 RangeSet New = getSymGERange(St, Sym, Int, Adjustment);
688 return New.isEmpty() ? nullptr : St->set<ConstraintRange>(Sym, New);
691 RangeSet RangeConstraintManager::getSymLERange(
692 llvm::function_ref<RangeSet()> RS,
693 const llvm::APSInt &Int,
694 const llvm::APSInt &Adjustment) {
695 // Before we do any real work, see if the value can even show up.
696 APSIntType AdjustmentType(Adjustment);
697 switch (AdjustmentType.testInRange(Int, true)) {
698 case APSIntType::RTR_Below:
699 return F.getEmptySet();
700 case APSIntType::RTR_Within:
702 case APSIntType::RTR_Above:
706 // Special case for Int == Max. This is always feasible.
707 llvm::APSInt ComparisonVal = AdjustmentType.convert(Int);
708 llvm::APSInt Max = AdjustmentType.getMaxValue();
709 if (ComparisonVal == Max)
712 llvm::APSInt Min = AdjustmentType.getMinValue();
713 llvm::APSInt Lower = Min - Adjustment;
714 llvm::APSInt Upper = ComparisonVal - Adjustment;
716 return RS().Intersect(getBasicVals(), F, Lower, Upper);
719 RangeSet RangeConstraintManager::getSymLERange(ProgramStateRef St,
721 const llvm::APSInt &Int,
722 const llvm::APSInt &Adjustment) {
723 return getSymLERange([&] { return getRange(St, Sym); }, Int, Adjustment);
727 RangeConstraintManager::assumeSymLE(ProgramStateRef St, SymbolRef Sym,
728 const llvm::APSInt &Int,
729 const llvm::APSInt &Adjustment) {
730 RangeSet New = getSymLERange(St, Sym, Int, Adjustment);
731 return New.isEmpty() ? nullptr : St->set<ConstraintRange>(Sym, New);
734 ProgramStateRef RangeConstraintManager::assumeSymWithinInclusiveRange(
735 ProgramStateRef State, SymbolRef Sym, const llvm::APSInt &From,
736 const llvm::APSInt &To, const llvm::APSInt &Adjustment) {
737 RangeSet New = getSymGERange(State, Sym, From, Adjustment);
740 RangeSet Out = getSymLERange([&] { return New; }, To, Adjustment);
741 return Out.isEmpty() ? nullptr : State->set<ConstraintRange>(Sym, Out);
744 ProgramStateRef RangeConstraintManager::assumeSymOutsideInclusiveRange(
745 ProgramStateRef State, SymbolRef Sym, const llvm::APSInt &From,
746 const llvm::APSInt &To, const llvm::APSInt &Adjustment) {
747 RangeSet RangeLT = getSymLTRange(State, Sym, From, Adjustment);
748 RangeSet RangeGT = getSymGTRange(State, Sym, To, Adjustment);
749 RangeSet New(RangeLT.addRange(F, RangeGT));
750 return New.isEmpty() ? nullptr : State->set<ConstraintRange>(Sym, New);
753 //===------------------------------------------------------------------------===
755 //===------------------------------------------------------------------------===/
757 void RangeConstraintManager::print(ProgramStateRef St, raw_ostream &Out,
758 const char *nl, const char *sep) {
760 ConstraintRangeTy Ranges = St->get<ConstraintRange>();
762 if (Ranges.isEmpty()) {
763 Out << nl << sep << "Ranges are empty." << nl;
767 Out << nl << sep << "Ranges of symbol values:";
768 for (ConstraintRangeTy::iterator I = Ranges.begin(), E = Ranges.end(); I != E;
770 Out << nl << ' ' << I.getKey() << " : ";
771 I.getData().print(Out);