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RangeConstraintManager.cpp
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1 //== RangeConstraintManager.cpp - Manage range constraints.------*- C++ -*--==//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // This file defines RangeConstraintManager, a class that tracks simple
11 // equality and inequality constraints on symbolic values of ProgramState.
12 //
13 //===----------------------------------------------------------------------===//
14 
19 #include "llvm/ADT/FoldingSet.h"
20 #include "llvm/ADT/ImmutableSet.h"
21 #include "llvm/Support/raw_ostream.h"
22 
23 using namespace clang;
24 using namespace ento;
25 
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.
29 namespace {
30 class Range : public std::pair<const llvm::APSInt *, const llvm::APSInt *> {
31 public:
32  Range(const llvm::APSInt &from, const llvm::APSInt &to)
33  : std::pair<const llvm::APSInt *, const llvm::APSInt *>(&from, &to) {
34  assert(from <= to);
35  }
36  bool Includes(const llvm::APSInt &v) const {
37  return *first <= v && v <= *second;
38  }
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;
43  }
44 
45  void Profile(llvm::FoldingSetNodeID &ID) const {
46  ID.AddPointer(&From());
47  ID.AddPointer(&To());
48  }
49 };
50 
51 class RangeTrait : public llvm::ImutContainerInfo<Range> {
52 public:
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);
60  }
61 };
62 
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.
66 class RangeSet {
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=
70  // to work.
71 public:
72  typedef PrimRangeSet::Factory Factory;
73  typedef PrimRangeSet::iterator iterator;
74 
75  RangeSet(PrimRangeSet RS) : ranges(RS) {}
76 
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);
84  }
85 
86  iterator begin() const { return ranges.begin(); }
87  iterator end() const { return ranges.end(); }
88 
89  bool isEmpty() const { return ranges.isEmpty(); }
90 
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))) {}
94 
95  /// Profile - Generates a hash profile of this RangeSet for use
96  /// by FoldingSet.
97  void Profile(llvm::FoldingSetNodeID &ID) const { ranges.Profile(ID); }
98 
99  /// getConcreteValue - If a symbol is contrained to equal a specific integer
100  /// constant then this method returns that value. Otherwise, it returns
101  /// NULL.
102  const llvm::APSInt *getConcreteValue() const {
103  return ranges.isSingleton() ? ranges.begin()->getConcreteValue() : nullptr;
104  }
105 
106 private:
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) {
121  continue;
122  }
123  if (i->From() > Upper) {
124  break;
125  }
126 
127  if (i->Includes(Lower)) {
128  if (i->Includes(Upper)) {
129  newRanges =
130  F.add(newRanges, Range(BV.getValue(Lower), BV.getValue(Upper)));
131  break;
132  } else
133  newRanges = F.add(newRanges, Range(BV.getValue(Lower), i->To()));
134  } else {
135  if (i->Includes(Upper)) {
136  newRanges = F.add(newRanges, Range(i->From(), BV.getValue(Upper)));
137  break;
138  } else
139  newRanges = F.add(newRanges, *i);
140  }
141  }
142  }
143 
144  const llvm::APSInt &getMinValue() const {
145  assert(!isEmpty());
146  return ranges.begin()->From();
147  }
148 
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);
158 
159  switch (LowerTest) {
161  switch (UpperTest) {
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.
165  if (Lower <= Upper)
166  return false;
167 
168  // However, if the range wraps around, it spans all possible values.
169  Lower = Type.getMinValue();
170  Upper = Type.getMaxValue();
171  break;
173  // The range starts below what's possible but ends within it. Pin.
174  Lower = Type.getMinValue();
175  Type.apply(Upper);
176  break;
178  // The range spans all possible values for the symbol. Pin.
179  Lower = Type.getMinValue();
180  Upper = Type.getMaxValue();
181  break;
182  }
183  break;
185  switch (UpperTest) {
187  // The range wraps around, but all lower values are not possible.
188  Type.apply(Lower);
189  Upper = Type.getMaxValue();
190  break;
192  // The range may or may not wrap around, but both limits are valid.
193  Type.apply(Lower);
194  Type.apply(Upper);
195  break;
197  // The range starts within what's possible but ends above it. Pin.
198  Type.apply(Lower);
199  Upper = Type.getMaxValue();
200  break;
201  }
202  break;
204  switch (UpperTest) {
206  // The range wraps but is outside the symbol's set of possible values.
207  return false;
209  // The range starts above what's possible but ends within it (wrap).
210  Lower = Type.getMinValue();
211  Type.apply(Upper);
212  break;
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.
216  if (Lower <= Upper)
217  return false;
218 
219  // However, if the range wraps around, it spans all possible values.
220  Lower = Type.getMinValue();
221  Upper = Type.getMaxValue();
222  break;
223  }
224  break;
225  }
226 
227  return true;
228  }
229 
230 public:
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();
242 
243  PrimRangeSet newRanges = F.getEmptySet();
244 
245  PrimRangeSet::iterator i = begin(), e = end();
246  if (Lower <= Upper)
247  IntersectInRange(BV, F, Lower, Upper, newRanges, i, e);
248  else {
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);
254  }
255 
256  return newRanges;
257  }
258 
259  void print(raw_ostream &os) const {
260  bool isFirst = true;
261  os << "{ ";
262  for (iterator i = begin(), e = end(); i != e; ++i) {
263  if (isFirst)
264  isFirst = false;
265  else
266  os << ", ";
267 
268  os << '[' << i->From().toString(10) << ", " << i->To().toString(10)
269  << ']';
270  }
271  os << " }";
272  }
273 
274  bool operator==(const RangeSet &other) const {
275  return ranges == other.ranges;
276  }
277 };
278 } // end anonymous namespace
279 
282  RangeSet))
283 
284 namespace {
285 class RangeConstraintManager : public SimpleConstraintManager {
286  RangeSet getRange(ProgramStateRef State, SymbolRef Sym);
287 
288 public:
289  RangeConstraintManager(SubEngine *SE, SValBuilder &SVB)
290  : SimpleConstraintManager(SE, SVB) {}
291 
292  ProgramStateRef assumeSymNE(ProgramStateRef State, SymbolRef Sym,
293  const llvm::APSInt &V,
294  const llvm::APSInt &Adjustment) override;
295 
296  ProgramStateRef assumeSymEQ(ProgramStateRef State, SymbolRef Sym,
297  const llvm::APSInt &V,
298  const llvm::APSInt &Adjustment) override;
299 
300  ProgramStateRef assumeSymLT(ProgramStateRef State, SymbolRef Sym,
301  const llvm::APSInt &V,
302  const llvm::APSInt &Adjustment) override;
303 
304  ProgramStateRef assumeSymGT(ProgramStateRef State, SymbolRef Sym,
305  const llvm::APSInt &V,
306  const llvm::APSInt &Adjustment) override;
307 
308  ProgramStateRef assumeSymLE(ProgramStateRef State, SymbolRef Sym,
309  const llvm::APSInt &V,
310  const llvm::APSInt &Adjustment) override;
311 
312  ProgramStateRef assumeSymGE(ProgramStateRef State, SymbolRef Sym,
313  const llvm::APSInt &V,
314  const llvm::APSInt &Adjustment) override;
315 
316  ProgramStateRef assumeSymbolWithinInclusiveRange(
317  ProgramStateRef State, SymbolRef Sym, const llvm::APSInt &From,
318  const llvm::APSInt &To, const llvm::APSInt &Adjustment) override;
319 
320  ProgramStateRef assumeSymbolOutOfInclusiveRange(
321  ProgramStateRef State, SymbolRef Sym, const llvm::APSInt &From,
322  const llvm::APSInt &To, const llvm::APSInt &Adjustment) override;
323 
324  const llvm::APSInt *getSymVal(ProgramStateRef St,
325  SymbolRef Sym) const override;
326  ConditionTruthVal checkNull(ProgramStateRef State, SymbolRef Sym) override;
327 
328  ProgramStateRef removeDeadBindings(ProgramStateRef St,
329  SymbolReaper &SymReaper) override;
330 
331  void print(ProgramStateRef St, raw_ostream &Out, const char *nl,
332  const char *sep) override;
333 
334 private:
335  RangeSet::Factory F;
336  RangeSet getSymLTRange(ProgramStateRef St, SymbolRef Sym,
337  const llvm::APSInt &Int,
338  const llvm::APSInt &Adjustment);
339  RangeSet getSymGTRange(ProgramStateRef St, SymbolRef Sym,
340  const llvm::APSInt &Int,
341  const llvm::APSInt &Adjustment);
342  RangeSet getSymLERange(ProgramStateRef St, SymbolRef Sym,
343  const llvm::APSInt &Int,
344  const llvm::APSInt &Adjustment);
345  RangeSet getSymLERange(const RangeSet &RS, const llvm::APSInt &Int,
346  const llvm::APSInt &Adjustment);
347  RangeSet getSymGERange(ProgramStateRef St, SymbolRef Sym,
348  const llvm::APSInt &Int,
349  const llvm::APSInt &Adjustment);
350 };
351 
352 } // end anonymous namespace
353 
354 std::unique_ptr<ConstraintManager>
356  return llvm::make_unique<RangeConstraintManager>(Eng, StMgr.getSValBuilder());
357 }
358 
359 const llvm::APSInt *RangeConstraintManager::getSymVal(ProgramStateRef St,
360  SymbolRef Sym) const {
361  const ConstraintRangeTy::data_type *T = St->get<ConstraintRange>(Sym);
362  return T ? T->getConcreteValue() : nullptr;
363 }
364 
365 ConditionTruthVal RangeConstraintManager::checkNull(ProgramStateRef State,
366  SymbolRef Sym) {
367  const RangeSet *Ranges = State->get<ConstraintRange>(Sym);
368 
369  // If we don't have any information about this symbol, it's underconstrained.
370  if (!Ranges)
371  return ConditionTruthVal();
372 
373  // If we have a concrete value, see if it's zero.
374  if (const llvm::APSInt *Value = Ranges->getConcreteValue())
375  return *Value == 0;
376 
377  BasicValueFactory &BV = getBasicVals();
378  APSIntType IntType = BV.getAPSIntType(Sym->getType());
379  llvm::APSInt Zero = IntType.getZeroValue();
380 
381  // Check if zero is in the set of possible values.
382  if (Ranges->Intersect(BV, F, Zero, Zero).isEmpty())
383  return false;
384 
385  // Zero is a possible value, but it is not the /only/ possible value.
386  return ConditionTruthVal();
387 }
388 
389 /// Scan all symbols referenced by the constraints. If the symbol is not alive
390 /// as marked in LSymbols, mark it as dead in DSymbols.
392 RangeConstraintManager::removeDeadBindings(ProgramStateRef State,
393  SymbolReaper &SymReaper) {
394  bool Changed = false;
395  ConstraintRangeTy CR = State->get<ConstraintRange>();
396  ConstraintRangeTy::Factory &CRFactory = State->get_context<ConstraintRange>();
397 
398  for (ConstraintRangeTy::iterator I = CR.begin(), E = CR.end(); I != E; ++I) {
399  SymbolRef Sym = I.getKey();
400  if (SymReaper.maybeDead(Sym)) {
401  Changed = true;
402  CR = CRFactory.remove(CR, Sym);
403  }
404  }
405 
406  return Changed ? State->set<ConstraintRange>(CR) : State;
407 }
408 
409 RangeSet RangeConstraintManager::getRange(ProgramStateRef State,
410  SymbolRef Sym) {
411  if (ConstraintRangeTy::data_type *V = State->get<ConstraintRange>(Sym))
412  return *V;
413 
414  // Lazily generate a new RangeSet representing all possible values for the
415  // given symbol type.
416  BasicValueFactory &BV = getBasicVals();
417  QualType T = Sym->getType();
418 
419  RangeSet Result(F, BV.getMinValue(T), BV.getMaxValue(T));
420 
421  // Special case: references are known to be non-zero.
422  if (T->isReferenceType()) {
423  APSIntType IntType = BV.getAPSIntType(T);
424  Result = Result.Intersect(BV, F, ++IntType.getZeroValue(),
425  --IntType.getZeroValue());
426  }
427 
428  return Result;
429 }
430 
431 //===------------------------------------------------------------------------===
432 // assumeSymX methods: public interface for RangeConstraintManager.
433 //===------------------------------------------------------------------------===/
434 
435 // The syntax for ranges below is mathematical, using [x, y] for closed ranges
436 // and (x, y) for open ranges. These ranges are modular, corresponding with
437 // a common treatment of C integer overflow. This means that these methods
438 // do not have to worry about overflow; RangeSet::Intersect can handle such a
439 // "wraparound" range.
440 // As an example, the range [UINT_MAX-1, 3) contains five values: UINT_MAX-1,
441 // UINT_MAX, 0, 1, and 2.
442 
444 RangeConstraintManager::assumeSymNE(ProgramStateRef St, SymbolRef Sym,
445  const llvm::APSInt &Int,
446  const llvm::APSInt &Adjustment) {
447  // Before we do any real work, see if the value can even show up.
448  APSIntType AdjustmentType(Adjustment);
449  if (AdjustmentType.testInRange(Int, true) != APSIntType::RTR_Within)
450  return St;
451 
452  llvm::APSInt Lower = AdjustmentType.convert(Int) - Adjustment;
453  llvm::APSInt Upper = Lower;
454  --Lower;
455  ++Upper;
456 
457  // [Int-Adjustment+1, Int-Adjustment-1]
458  // Notice that the lower bound is greater than the upper bound.
459  RangeSet New = getRange(St, Sym).Intersect(getBasicVals(), F, Upper, Lower);
460  return New.isEmpty() ? nullptr : St->set<ConstraintRange>(Sym, New);
461 }
462 
464 RangeConstraintManager::assumeSymEQ(ProgramStateRef St, SymbolRef Sym,
465  const llvm::APSInt &Int,
466  const llvm::APSInt &Adjustment) {
467  // Before we do any real work, see if the value can even show up.
468  APSIntType AdjustmentType(Adjustment);
469  if (AdjustmentType.testInRange(Int, true) != APSIntType::RTR_Within)
470  return nullptr;
471 
472  // [Int-Adjustment, Int-Adjustment]
473  llvm::APSInt AdjInt = AdjustmentType.convert(Int) - Adjustment;
474  RangeSet New = getRange(St, Sym).Intersect(getBasicVals(), F, AdjInt, AdjInt);
475  return New.isEmpty() ? nullptr : St->set<ConstraintRange>(Sym, New);
476 }
477 
478 RangeSet RangeConstraintManager::getSymLTRange(ProgramStateRef St,
479  SymbolRef Sym,
480  const llvm::APSInt &Int,
481  const llvm::APSInt &Adjustment) {
482  // Before we do any real work, see if the value can even show up.
483  APSIntType AdjustmentType(Adjustment);
484  switch (AdjustmentType.testInRange(Int, true)) {
486  return F.getEmptySet();
488  break;
490  return getRange(St, Sym);
491  }
492 
493  // Special case for Int == Min. This is always false.
494  llvm::APSInt ComparisonVal = AdjustmentType.convert(Int);
495  llvm::APSInt Min = AdjustmentType.getMinValue();
496  if (ComparisonVal == Min)
497  return F.getEmptySet();
498 
499  llvm::APSInt Lower = Min - Adjustment;
500  llvm::APSInt Upper = ComparisonVal - Adjustment;
501  --Upper;
502 
503  return getRange(St, Sym).Intersect(getBasicVals(), F, Lower, Upper);
504 }
505 
507 RangeConstraintManager::assumeSymLT(ProgramStateRef St, SymbolRef Sym,
508  const llvm::APSInt &Int,
509  const llvm::APSInt &Adjustment) {
510  RangeSet New = getSymLTRange(St, Sym, Int, Adjustment);
511  return New.isEmpty() ? nullptr : St->set<ConstraintRange>(Sym, New);
512 }
513 
514 RangeSet RangeConstraintManager::getSymGTRange(ProgramStateRef St,
515  SymbolRef Sym,
516  const llvm::APSInt &Int,
517  const llvm::APSInt &Adjustment) {
518  // Before we do any real work, see if the value can even show up.
519  APSIntType AdjustmentType(Adjustment);
520  switch (AdjustmentType.testInRange(Int, true)) {
522  return getRange(St, Sym);
524  break;
526  return F.getEmptySet();
527  }
528 
529  // Special case for Int == Max. This is always false.
530  llvm::APSInt ComparisonVal = AdjustmentType.convert(Int);
531  llvm::APSInt Max = AdjustmentType.getMaxValue();
532  if (ComparisonVal == Max)
533  return F.getEmptySet();
534 
535  llvm::APSInt Lower = ComparisonVal - Adjustment;
536  llvm::APSInt Upper = Max - Adjustment;
537  ++Lower;
538 
539  return getRange(St, Sym).Intersect(getBasicVals(), F, Lower, Upper);
540 }
541 
543 RangeConstraintManager::assumeSymGT(ProgramStateRef St, SymbolRef Sym,
544  const llvm::APSInt &Int,
545  const llvm::APSInt &Adjustment) {
546  RangeSet New = getSymGTRange(St, Sym, Int, Adjustment);
547  return New.isEmpty() ? nullptr : St->set<ConstraintRange>(Sym, New);
548 }
549 
550 RangeSet RangeConstraintManager::getSymGERange(ProgramStateRef St,
551  SymbolRef Sym,
552  const llvm::APSInt &Int,
553  const llvm::APSInt &Adjustment) {
554  // Before we do any real work, see if the value can even show up.
555  APSIntType AdjustmentType(Adjustment);
556  switch (AdjustmentType.testInRange(Int, true)) {
558  return getRange(St, Sym);
560  break;
562  return F.getEmptySet();
563  }
564 
565  // Special case for Int == Min. This is always feasible.
566  llvm::APSInt ComparisonVal = AdjustmentType.convert(Int);
567  llvm::APSInt Min = AdjustmentType.getMinValue();
568  if (ComparisonVal == Min)
569  return getRange(St, Sym);
570 
571  llvm::APSInt Max = AdjustmentType.getMaxValue();
572  llvm::APSInt Lower = ComparisonVal - Adjustment;
573  llvm::APSInt Upper = Max - Adjustment;
574 
575  return getRange(St, Sym).Intersect(getBasicVals(), F, Lower, Upper);
576 }
577 
579 RangeConstraintManager::assumeSymGE(ProgramStateRef St, SymbolRef Sym,
580  const llvm::APSInt &Int,
581  const llvm::APSInt &Adjustment) {
582  RangeSet New = getSymGERange(St, Sym, Int, Adjustment);
583  return New.isEmpty() ? nullptr : St->set<ConstraintRange>(Sym, New);
584 }
585 
586 RangeSet RangeConstraintManager::getSymLERange(const RangeSet &RS,
587  const llvm::APSInt &Int,
588  const llvm::APSInt &Adjustment) {
589  // Before we do any real work, see if the value can even show up.
590  APSIntType AdjustmentType(Adjustment);
591  switch (AdjustmentType.testInRange(Int, true)) {
593  return F.getEmptySet();
595  break;
597  return RS;
598  }
599 
600  // Special case for Int == Max. This is always feasible.
601  llvm::APSInt ComparisonVal = AdjustmentType.convert(Int);
602  llvm::APSInt Max = AdjustmentType.getMaxValue();
603  if (ComparisonVal == Max)
604  return RS;
605 
606  llvm::APSInt Min = AdjustmentType.getMinValue();
607  llvm::APSInt Lower = Min - Adjustment;
608  llvm::APSInt Upper = ComparisonVal - Adjustment;
609 
610  return RS.Intersect(getBasicVals(), F, Lower, Upper);
611 }
612 
613 RangeSet RangeConstraintManager::getSymLERange(ProgramStateRef St,
614  SymbolRef Sym,
615  const llvm::APSInt &Int,
616  const llvm::APSInt &Adjustment) {
617  // Before we do any real work, see if the value can even show up.
618  APSIntType AdjustmentType(Adjustment);
619  switch (AdjustmentType.testInRange(Int, true)) {
621  return F.getEmptySet();
623  break;
625  return getRange(St, Sym);
626  }
627 
628  // Special case for Int == Max. This is always feasible.
629  llvm::APSInt ComparisonVal = AdjustmentType.convert(Int);
630  llvm::APSInt Max = AdjustmentType.getMaxValue();
631  if (ComparisonVal == Max)
632  return getRange(St, Sym);
633 
634  llvm::APSInt Min = AdjustmentType.getMinValue();
635  llvm::APSInt Lower = Min - Adjustment;
636  llvm::APSInt Upper = ComparisonVal - Adjustment;
637 
638  return getRange(St, Sym).Intersect(getBasicVals(), F, Lower, Upper);
639 }
640 
642 RangeConstraintManager::assumeSymLE(ProgramStateRef St, SymbolRef Sym,
643  const llvm::APSInt &Int,
644  const llvm::APSInt &Adjustment) {
645  RangeSet New = getSymLERange(St, Sym, Int, Adjustment);
646  return New.isEmpty() ? nullptr : St->set<ConstraintRange>(Sym, New);
647 }
648 
649 ProgramStateRef RangeConstraintManager::assumeSymbolWithinInclusiveRange(
650  ProgramStateRef State, SymbolRef Sym, const llvm::APSInt &From,
651  const llvm::APSInt &To, const llvm::APSInt &Adjustment) {
652  RangeSet New = getSymGERange(State, Sym, From, Adjustment);
653  if (New.isEmpty())
654  return nullptr;
655  New = getSymLERange(New, To, Adjustment);
656  return New.isEmpty() ? nullptr : State->set<ConstraintRange>(Sym, New);
657 }
658 
659 ProgramStateRef RangeConstraintManager::assumeSymbolOutOfInclusiveRange(
660  ProgramStateRef State, SymbolRef Sym, const llvm::APSInt &From,
661  const llvm::APSInt &To, const llvm::APSInt &Adjustment) {
662  RangeSet RangeLT = getSymLTRange(State, Sym, From, Adjustment);
663  RangeSet RangeGT = getSymGTRange(State, Sym, To, Adjustment);
664  RangeSet New(RangeLT.addRange(F, RangeGT));
665  return New.isEmpty() ? nullptr : State->set<ConstraintRange>(Sym, New);
666 }
667 
668 //===------------------------------------------------------------------------===
669 // Pretty-printing.
670 //===------------------------------------------------------------------------===/
671 
672 void RangeConstraintManager::print(ProgramStateRef St, raw_ostream &Out,
673  const char *nl, const char *sep) {
674 
675  ConstraintRangeTy Ranges = St->get<ConstraintRange>();
676 
677  if (Ranges.isEmpty()) {
678  Out << nl << sep << "Ranges are empty." << nl;
679  return;
680  }
681 
682  Out << nl << sep << "Ranges of symbol values:";
683  for (ConstraintRangeTy::iterator I = Ranges.begin(), E = Ranges.end(); I != E;
684  ++I) {
685  Out << nl << ' ' << I.getKey() << " : ";
686  I.getData().print(Out);
687  }
688  Out << nl;
689 }
A (possibly-)qualified type.
Definition: Type.h:599
Value is less than the minimum representable value.
Definition: APSIntType.h:78
bool operator==(CanQual< T > x, CanQual< U > y)
DominatorTree GraphTraits specialization so the DominatorTree can be iterable by generic graph iterat...
Definition: Dominators.h:26
bool maybeDead(SymbolRef sym)
If a symbol is known to be live, marks the symbol as live.
std::unique_ptr< ConstraintManager > CreateRangeConstraintManager(ProgramStateManager &statemgr, SubEngine *subengine)
The base class of the type hierarchy.
Definition: Type.h:1283
Symbolic value.
Definition: SymExpr.h:29
LineState State
Definition: Format.h:889
bool isReferenceType() const
Definition: Type.h:5598
Value is representable using this type.
Definition: APSIntType.h:79
A record of the "type" of an APSInt, used for conversions.
Definition: APSIntType.h:20
RangeTestResultKind testInRange(const llvm::APSInt &Val, bool AllowMixedSign) const LLVM_READONLY
Tests whether a given value is losslessly representable using this type.
Definition: APSIntType.cpp:16
llvm::APSInt getZeroValue() const LLVM_READONLY
Returns an all-zero value for this type.
Definition: APSIntType.h:56
virtual QualType getType() const =0
ID
Defines the set of possible language-specific address spaces.
Definition: AddressSpaces.h:27
llvm::APSInt getMinValue() const LLVM_READONLY
Returns the minimum value for this type.
Definition: APSIntType.h:61
REGISTER_TRAIT_WITH_PROGRAMSTATE(ConstraintRange, CLANG_ENTO_PROGRAMSTATE_MAP(SymbolRef, RangeSet)) namespace
The result type of a method or function.
do v
Definition: arm_acle.h:78
llvm::APSInt getMaxValue() const LLVM_READONLY
Returns the maximum value for this type.
Definition: APSIntType.h:66
#define CLANG_ENTO_PROGRAMSTATE_MAP(Key, Value)
Helper for registering a map trait.
A class responsible for cleaning up unused symbols.
Value is greater than the maximum representable value.
Definition: APSIntType.h:80
RangeTestResultKind
Used to classify whether a value is representable using this type.
Definition: APSIntType.h:77
llvm::APSInt convert(const llvm::APSInt &Value) const LLVM_READONLY
Convert and return a new APSInt with the given value, but this type&#39;s bit width and signedness...
Definition: APSIntType.h:49
/file This file defines classes for searching and anlyzing source code clones.
const llvm::APSInt & getMinValue(const llvm::APSInt &v)
APSIntType getAPSIntType(QualType T) const
Returns the type of the APSInt used to store values of the given QualType.
const llvm::APSInt & getMaxValue(const llvm::APSInt &v)