ProgramStateRef SimpleConstraintManager::assumeInclusiveRange(
    ProgramStateRef State, NonLoc Value, const llvm::APSInt &From,
    const llvm::APSInt &To, bool InRange) {

  assert(From.isUnsigned() == To.isUnsigned() &&
         From.getBitWidth() == To.getBitWidth() &&
         "Values should have same types!");

  if (!canReasonAbout(Value)) {
    // Just add the constraint to the expression without trying to simplify.
    SymbolRef Sym = Value.getAsSymExpr();
    assert(Sym);
    return assumeSymWithinInclusiveRange(State, Sym, From, To, InRange);
  }

  switch (Value.getSubKind()) {
  default:
    llvm_unreachable("'assumeInclusiveRange' is not implemented"
                     "for this NonLoc");

  case nonloc::LocAsIntegerKind:
  case nonloc::SymbolValKind: {
    if (SymbolRef Sym = Value.getAsSymbol())
      return assumeSymWithinInclusiveRange(State, Sym, From, To, InRange);
    return State;
  } // end switch

  case nonloc::ConcreteIntKind: {
    const llvm::APSInt &IntVal = Value.castAs<nonloc::ConcreteInt>().getValue();
    bool IsInRange = IntVal >= From && IntVal <= To;
    bool isFeasible = (IsInRange == InRange);
    return isFeasible ? State : nullptr;
  }
  } // end switch
}
ProgramStateRef 
BasicConstraintManager::assumeSymLE(ProgramStateRef state,
                                    SymbolRef sym,
                                    const llvm::APSInt &V,
                                    const llvm::APSInt &Adjustment) {
  // Reject a path if the value of sym is a constant X and !(X+Adj <= V).
  if (const llvm::APSInt* X = getSymVal(state, sym)) {
    bool isFeasible = (*X <= V-Adjustment);
    return isFeasible ? state : NULL;
  }

  // Sym is not a constant, but it is worth looking to see if V is the
  // minimum integer value.
  if (V == llvm::APSInt::getMinValue(V.getBitWidth(), V.isUnsigned())) {
    llvm::APSInt Adjusted = V-Adjustment;

    // If we know that sym != V (after adjustment), then this condition
    // is infeasible since there is no other value less than V.
    bool isFeasible = !isNotEqual(state, sym, Adjusted);

    // If the path is still feasible then as a consequence we know that
    // 'sym+Adjustment == V' because there are no smaller values.
    // Add this constraint.
    return isFeasible ? AddEQ(state, sym, Adjusted) : NULL;
  }

  return state;
}
ProgramStateRef 
BasicConstraintManager::assumeSymGT(ProgramStateRef state,
                                    SymbolRef sym,
                                    const llvm::APSInt &V,
                                    const llvm::APSInt &Adjustment) {
  // Is 'V' the largest possible value?
  if (V == llvm::APSInt::getMaxValue(V.getBitWidth(), V.isUnsigned())) {
    // sym cannot be any value greater than 'V'.  This path is infeasible.
    return NULL;
  }

  // FIXME: For now have assuming x > y be the same as assuming sym != V;
  return assumeSymNE(state, sym, V, Adjustment);
}
Ejemplo n.º 4
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TemplateArgument::TemplateArgument(ASTContext &Ctx, const llvm::APSInt &Value,
                                   QualType Type) {
  Integer.Kind = Integral;
  // Copy the APSInt value into our decomposed form.
  Integer.BitWidth = Value.getBitWidth();
  Integer.IsUnsigned = Value.isUnsigned();
  // If the value is large, we have to get additional memory from the ASTContext
  unsigned NumWords = Value.getNumWords();
  if (NumWords > 1) {
    void *Mem = Ctx.Allocate(NumWords * sizeof(uint64_t));
    std::memcpy(Mem, Value.getRawData(), NumWords * sizeof(uint64_t));
    Integer.pVal = static_cast<uint64_t *>(Mem);
  } else {
    Integer.VAL = Value.getZExtValue();
  }

  Integer.Type = Type.getAsOpaquePtr();
}
Ejemplo n.º 5
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 bool isUnsigned() const { return Val.isUnsigned(); }