本文整理汇总了C++中APSIntType::getZeroValue方法的典型用法代码示例。如果您正苦于以下问题：C++ APSIntType::getZeroValue方法的具体用法？C++ APSIntType::getZeroValue怎么用？C++ APSIntType::getZeroValue使用的例子？那么, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在类APSIntType的用法示例。
在下文中一共展示了APSIntType::getZeroValue方法的2个代码示例，这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞，您的评价将有助于系统推荐出更棒的C++代码示例。
示例1: checkNull
ConditionTruthVal RangeConstraintManager::checkNull(ProgramStateRef State,
SymbolRef Sym) {
const RangeSet *Ranges = State->get<ConstraintRange>(Sym);
// If we don't have any information about this symbol, it's underconstrained.
if (!Ranges)
return ConditionTruthVal();
// If we have a concrete value, see if it's zero.
if (const llvm::APSInt *Value = Ranges->getConcreteValue())
return *Value == 0;
BasicValueFactory &BV = getBasicVals();
APSIntType IntType = BV.getAPSIntType(Sym->getType());
llvm::APSInt Zero = IntType.getZeroValue();
// Check if zero is in the set of possible values.
if (Ranges->Intersect(BV, F, Zero, Zero).isEmpty())
return false;
// Zero is a possible value, but it is not the /only/ possible value.
return ConditionTruthVal();
}示例2: assumeSymRel
ProgramStateRef SimpleConstraintManager::assumeSymRel(ProgramStateRef State,
const SymExpr *LHS,
BinaryOperator::Opcode Op,
const llvm::APSInt &Int) {
assert(BinaryOperator::isComparisonOp(Op) &&
"Non-comparison ops should be rewritten as comparisons to zero.");
SymbolRef Sym = LHS;
// Simplification: translate an assume of a constraint of the form
// "(exp comparison_op expr) != 0" to true into an assume of
// "exp comparison_op expr" to true. (And similarly, an assume of the form
// "(exp comparison_op expr) == 0" to true into an assume of
// "exp comparison_op expr" to false.)
if (Int == 0 && (Op == BO_EQ || Op == BO_NE)) {
if (const BinarySymExpr *SE = dyn_cast<BinarySymExpr>(Sym))
if (BinaryOperator::isComparisonOp(SE->getOpcode()))
return assume(State, nonloc::SymbolVal(Sym), (Op == BO_NE ? true : false));
}
// Get the type used for calculating wraparound.
BasicValueFactory &BVF = getBasicVals();
APSIntType WraparoundType = BVF.getAPSIntType(LHS->getType());
// We only handle simple comparisons of the form "$sym == constant"
// or "($sym+constant1) == constant2".
// The adjustment is "constant1" in the above expression. It's used to
// "slide" the solution range around for modular arithmetic. For example,
// x < 4 has the solution [0, 3]. x+2 < 4 has the solution [0-2, 3-2], which
// in modular arithmetic is [0, 1] U [UINT_MAX-1, UINT_MAX]. It's up to
// the subclasses of SimpleConstraintManager to handle the adjustment.
llvm::APSInt Adjustment = WraparoundType.getZeroValue();
computeAdjustment(Sym, Adjustment);
// Convert the right-hand side integer as necessary.
APSIntType ComparisonType = std::max(WraparoundType, APSIntType(Int));
llvm::APSInt ConvertedInt = ComparisonType.convert(Int);
// Prefer unsigned comparisons.
if (ComparisonType.getBitWidth() == WraparoundType.getBitWidth() &&
ComparisonType.isUnsigned() && !WraparoundType.isUnsigned())
Adjustment.setIsSigned(false);
switch (Op) {
default:
llvm_unreachable("invalid operation not caught by assertion above");
case BO_EQ:
return assumeSymEQ(State, Sym, ConvertedInt, Adjustment);
case BO_NE:
return assumeSymNE(State, Sym, ConvertedInt, Adjustment);
case BO_GT:
return assumeSymGT(State, Sym, ConvertedInt, Adjustment);
case BO_GE:
return assumeSymGE(State, Sym, ConvertedInt, Adjustment);
case BO_LT:
return assumeSymLT(State, Sym, ConvertedInt, Adjustment);
case BO_LE:
return assumeSymLE(State, Sym, ConvertedInt, Adjustment);
} // end switch
}