843 lines
30 KiB
C++
843 lines
30 KiB
C++
//===-- IteratorPastEndChecker.cpp --------------------------------*- C++ -*--//
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//
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// The LLVM Compiler Infrastructure
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//
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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//
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// Defines a checker for using iterators outside their range (past end). Usage
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// means here dereferencing, incrementing etc.
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//
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//===----------------------------------------------------------------------===//
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#include "ClangSACheckers.h"
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#include "clang/StaticAnalyzer/Core/BugReporter/BugType.h"
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#include "clang/StaticAnalyzer/Core/Checker.h"
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#include "clang/StaticAnalyzer/Core/PathSensitive/CallEvent.h"
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#include "clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h"
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#include <utility>
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using namespace clang;
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using namespace ento;
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namespace {
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struct IteratorPosition {
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private:
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enum Kind { InRange, OutofRange } K;
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IteratorPosition(Kind InK) : K(InK) {}
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public:
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bool isInRange() const { return K == InRange; }
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bool isOutofRange() const { return K == OutofRange; }
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static IteratorPosition getInRange() { return IteratorPosition(InRange); }
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static IteratorPosition getOutofRange() {
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return IteratorPosition(OutofRange);
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}
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bool operator==(const IteratorPosition &X) const { return K == X.K; }
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bool operator!=(const IteratorPosition &X) const { return K != X.K; }
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void Profile(llvm::FoldingSetNodeID &ID) const { ID.AddInteger(K); }
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};
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typedef llvm::PointerUnion<const MemRegion *, SymbolRef> RegionOrSymbol;
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struct IteratorComparison {
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private:
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RegionOrSymbol Left, Right;
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bool Equality;
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public:
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IteratorComparison(RegionOrSymbol L, RegionOrSymbol R, bool Eq)
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: Left(L), Right(R), Equality(Eq) {}
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RegionOrSymbol getLeft() const { return Left; }
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RegionOrSymbol getRight() const { return Right; }
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bool isEquality() const { return Equality; }
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bool operator==(const IteratorComparison &X) const {
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return Left == X.Left && Right == X.Right && Equality == X.Equality;
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}
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bool operator!=(const IteratorComparison &X) const {
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return Left != X.Left || Right != X.Right || Equality != X.Equality;
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}
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void Profile(llvm::FoldingSetNodeID &ID) const { ID.AddInteger(Equality); }
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};
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class IteratorPastEndChecker
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: public Checker<
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check::PreCall, check::PostCall, check::PreStmt<CXXOperatorCallExpr>,
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check::PostStmt<CXXConstructExpr>, check::PostStmt<DeclStmt>,
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check::PostStmt<MaterializeTemporaryExpr>, check::BeginFunction,
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check::DeadSymbols, eval::Assume, eval::Call> {
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mutable IdentifierInfo *II_find = nullptr,
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*II_find_end = nullptr, *II_find_first_of = nullptr,
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*II_find_if = nullptr, *II_find_if_not = nullptr,
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*II_lower_bound = nullptr, *II_upper_bound = nullptr,
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*II_search = nullptr, *II_search_n = nullptr;
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std::unique_ptr<BugType> PastEndBugType;
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void handleComparison(CheckerContext &C, const SVal &RetVal, const SVal &LVal,
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const SVal &RVal, OverloadedOperatorKind Op) const;
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void handleAccess(CheckerContext &C, const SVal &Val) const;
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void handleDecrement(CheckerContext &C, const SVal &Val) const;
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void handleEnd(CheckerContext &C, const SVal &RetVal) const;
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bool evalFind(CheckerContext &C, const CallExpr *CE) const;
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bool evalFindEnd(CheckerContext &C, const CallExpr *CE) const;
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bool evalFindFirstOf(CheckerContext &C, const CallExpr *CE) const;
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bool evalFindIf(CheckerContext &C, const CallExpr *CE) const;
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bool evalFindIfNot(CheckerContext &C, const CallExpr *CE) const;
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bool evalLowerBound(CheckerContext &C, const CallExpr *CE) const;
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bool evalUpperBound(CheckerContext &C, const CallExpr *CE) const;
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bool evalSearch(CheckerContext &C, const CallExpr *CE) const;
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bool evalSearchN(CheckerContext &C, const CallExpr *CE) const;
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void Find(CheckerContext &C, const CallExpr *CE) const;
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void reportPastEndBug(const StringRef &Message, const SVal &Val,
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CheckerContext &C, ExplodedNode *ErrNode) const;
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void initIdentifiers(ASTContext &Ctx) const;
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public:
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IteratorPastEndChecker();
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void checkPreCall(const CallEvent &Call, CheckerContext &C) const;
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void checkPostCall(const CallEvent &Call, CheckerContext &C) const;
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void checkPreStmt(const CXXOperatorCallExpr *COCE, CheckerContext &C) const;
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void checkBeginFunction(CheckerContext &C) const;
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void checkPostStmt(const CXXConstructExpr *CCE, CheckerContext &C) const;
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void checkPostStmt(const DeclStmt *DS, CheckerContext &C) const;
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void checkPostStmt(const MaterializeTemporaryExpr *MTE,
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CheckerContext &C) const;
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void checkDeadSymbols(SymbolReaper &SR, CheckerContext &C) const;
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ProgramStateRef evalAssume(ProgramStateRef State, SVal Cond,
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bool Assumption) const;
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bool evalCall(const CallExpr *CE, CheckerContext &C) const;
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};
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}
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REGISTER_MAP_WITH_PROGRAMSTATE(IteratorSymbolMap, SymbolRef, IteratorPosition)
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REGISTER_MAP_WITH_PROGRAMSTATE(IteratorRegionMap, const MemRegion *,
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IteratorPosition)
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REGISTER_MAP_WITH_PROGRAMSTATE(IteratorComparisonMap, const SymExpr *,
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IteratorComparison)
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#define INIT_ID(Id) \
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if (!II_##Id) \
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II_##Id = &Ctx.Idents.get(#Id)
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namespace {
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bool isIteratorType(const QualType &Type);
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bool isIterator(const CXXRecordDecl *CRD);
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bool isEndCall(const FunctionDecl *Func);
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bool isSimpleComparisonOperator(OverloadedOperatorKind OK);
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bool isAccessOperator(OverloadedOperatorKind OK);
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bool isDecrementOperator(OverloadedOperatorKind OK);
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BinaryOperator::Opcode getOpcode(const SymExpr *SE);
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const RegionOrSymbol getRegionOrSymbol(const SVal &Val);
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const ProgramStateRef processComparison(ProgramStateRef State,
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RegionOrSymbol LVal,
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RegionOrSymbol RVal, bool Equal);
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const ProgramStateRef saveComparison(ProgramStateRef State,
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const SymExpr *Condition, const SVal &LVal,
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const SVal &RVal, bool Eq);
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const IteratorComparison *loadComparison(ProgramStateRef State,
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const SymExpr *Condition);
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const IteratorPosition *getIteratorPosition(ProgramStateRef State,
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const SVal &Val);
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const IteratorPosition *getIteratorPosition(ProgramStateRef State,
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RegionOrSymbol RegOrSym);
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ProgramStateRef setIteratorPosition(ProgramStateRef State, const SVal &Val,
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IteratorPosition Pos);
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ProgramStateRef setIteratorPosition(ProgramStateRef State,
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RegionOrSymbol RegOrSym,
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IteratorPosition Pos);
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ProgramStateRef adjustIteratorPosition(ProgramStateRef State,
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RegionOrSymbol RegOrSym,
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IteratorPosition Pos, bool Equal);
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bool contradictingIteratorPositions(IteratorPosition Pos1,
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IteratorPosition Pos2, bool Equal);
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}
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IteratorPastEndChecker::IteratorPastEndChecker() {
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PastEndBugType.reset(
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new BugType(this, "Iterator Past End", "Misuse of STL APIs"));
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PastEndBugType->setSuppressOnSink(true);
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}
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void IteratorPastEndChecker::checkPreCall(const CallEvent &Call,
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CheckerContext &C) const {
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// Check for access past end
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const auto *Func = Call.getDecl()->getAsFunction();
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if (!Func)
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return;
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if (Func->isOverloadedOperator()) {
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if (isAccessOperator(Func->getOverloadedOperator())) {
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if (const auto *InstCall = dyn_cast<CXXInstanceCall>(&Call)) {
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handleAccess(C, InstCall->getCXXThisVal());
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} else {
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handleAccess(C, Call.getArgSVal(0));
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}
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}
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}
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}
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void IteratorPastEndChecker::checkPostCall(const CallEvent &Call,
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CheckerContext &C) const {
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// Record end() iterators, iterator decrementation and comparison
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const auto *Func = Call.getDecl()->getAsFunction();
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if (!Func)
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return;
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if (Func->isOverloadedOperator()) {
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const auto Op = Func->getOverloadedOperator();
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if (isSimpleComparisonOperator(Op)) {
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if (Func->isCXXInstanceMember()) {
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const auto &InstCall = static_cast<const CXXInstanceCall &>(Call);
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handleComparison(C, InstCall.getReturnValue(), InstCall.getCXXThisVal(),
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InstCall.getArgSVal(0), Op);
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} else {
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handleComparison(C, Call.getReturnValue(), Call.getArgSVal(0),
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Call.getArgSVal(1), Op);
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}
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} else if (isDecrementOperator(Func->getOverloadedOperator())) {
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if (Func->isCXXInstanceMember()) {
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const auto &InstCall = static_cast<const CXXInstanceCall &>(Call);
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handleDecrement(C, InstCall.getCXXThisVal());
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} else {
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handleDecrement(C, Call.getArgSVal(0));
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}
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}
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} else if (Func->isCXXInstanceMember()) {
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if (!isEndCall(Func))
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return;
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if (!isIteratorType(Call.getResultType()))
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return;
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handleEnd(C, Call.getReturnValue());
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}
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}
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void IteratorPastEndChecker::checkPreStmt(const CXXOperatorCallExpr *COCE,
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CheckerContext &C) const {
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const auto *ThisExpr = COCE->getArg(0);
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auto State = C.getState();
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const auto *LCtx = C.getPredecessor()->getLocationContext();
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const auto CurrentThis = State->getSVal(ThisExpr, LCtx);
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if (const auto *Reg = CurrentThis.getAsRegion()) {
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if (!Reg->getAs<CXXTempObjectRegion>())
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return;
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const auto OldState = C.getPredecessor()->getFirstPred()->getState();
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const auto OldThis = OldState->getSVal(ThisExpr, LCtx);
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const auto *Pos = getIteratorPosition(OldState, OldThis);
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if (!Pos)
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return;
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State = setIteratorPosition(State, CurrentThis, *Pos);
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C.addTransition(State);
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}
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}
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void IteratorPastEndChecker::checkBeginFunction(CheckerContext &C) const {
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// Copy state of iterator arguments to iterator parameters
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auto State = C.getState();
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const auto *LCtx = C.getLocationContext();
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const auto *Site = cast<StackFrameContext>(LCtx)->getCallSite();
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if (!Site)
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return;
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const auto *FD = dyn_cast<FunctionDecl>(LCtx->getDecl());
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if (!FD)
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return;
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const auto *CE = dyn_cast<CallExpr>(Site);
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if (!CE)
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return;
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bool Change = false;
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int idx = 0;
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for (const auto P : FD->parameters()) {
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auto Param = State->getLValue(P, LCtx);
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auto Arg = State->getSVal(CE->getArg(idx++), LCtx->getParent());
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const auto *Pos = getIteratorPosition(State, Arg);
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if (!Pos)
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continue;
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State = setIteratorPosition(State, Param, *Pos);
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Change = true;
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}
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if (Change) {
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C.addTransition(State);
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}
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}
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void IteratorPastEndChecker::checkPostStmt(const CXXConstructExpr *CCE,
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CheckerContext &C) const {
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// Transfer iterator state in case of copy or move by constructor
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const auto *ctr = CCE->getConstructor();
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if (!ctr->isCopyOrMoveConstructor())
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return;
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const auto *RHSExpr = CCE->getArg(0);
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auto State = C.getState();
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const auto *LCtx = C.getLocationContext();
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const auto RetVal = State->getSVal(CCE, LCtx);
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const auto RHSVal = State->getSVal(RHSExpr, LCtx);
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const auto *RHSPos = getIteratorPosition(State, RHSVal);
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if (!RHSPos)
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return;
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State = setIteratorPosition(State, RetVal, *RHSPos);
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C.addTransition(State);
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}
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void IteratorPastEndChecker::checkPostStmt(const DeclStmt *DS,
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CheckerContext &C) const {
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// Transfer iterator state to new variable declaration
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for (const auto *D : DS->decls()) {
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const auto *VD = dyn_cast<VarDecl>(D);
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if (!VD || !VD->hasInit())
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continue;
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auto State = C.getState();
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const auto *LCtx = C.getPredecessor()->getLocationContext();
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const auto *Pos =
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getIteratorPosition(State, State->getSVal(VD->getInit(), LCtx));
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if (!Pos)
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continue;
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State = setIteratorPosition(State, State->getLValue(VD, LCtx), *Pos);
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C.addTransition(State);
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}
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}
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void IteratorPastEndChecker::checkPostStmt(const MaterializeTemporaryExpr *MTE,
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CheckerContext &C) const {
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/* Transfer iterator state for to temporary objects */
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auto State = C.getState();
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const auto *LCtx = C.getPredecessor()->getLocationContext();
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const auto *Pos =
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getIteratorPosition(State, State->getSVal(MTE->GetTemporaryExpr(), LCtx));
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if (!Pos)
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return;
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State = setIteratorPosition(State, State->getSVal(MTE, LCtx), *Pos);
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C.addTransition(State);
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}
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void IteratorPastEndChecker::checkDeadSymbols(SymbolReaper &SR,
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CheckerContext &C) const {
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auto State = C.getState();
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auto RegionMap = State->get<IteratorRegionMap>();
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for (const auto Reg : RegionMap) {
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if (!SR.isLiveRegion(Reg.first)) {
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State = State->remove<IteratorRegionMap>(Reg.first);
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}
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}
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auto SymbolMap = State->get<IteratorSymbolMap>();
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for (const auto Sym : SymbolMap) {
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if (SR.isDead(Sym.first)) {
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State = State->remove<IteratorSymbolMap>(Sym.first);
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}
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}
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auto ComparisonMap = State->get<IteratorComparisonMap>();
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for (const auto Comp : ComparisonMap) {
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if (SR.isDead(Comp.first)) {
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State = State->remove<IteratorComparisonMap>(Comp.first);
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}
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}
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}
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ProgramStateRef IteratorPastEndChecker::evalAssume(ProgramStateRef State,
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SVal Cond,
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bool Assumption) const {
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// Load recorded comparison and transfer iterator state between sides
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// according to comparison operator and assumption
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const auto *SE = Cond.getAsSymExpr();
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if (!SE)
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return State;
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auto Opc = getOpcode(SE);
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if (Opc != BO_EQ && Opc != BO_NE)
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return State;
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bool Negated = false;
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const auto *Comp = loadComparison(State, SE);
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if (!Comp) {
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// Try negated comparison, which is a SymExpr to 0 integer comparison
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const auto *SIE = dyn_cast<SymIntExpr>(SE);
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if (!SIE)
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return State;
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if (SIE->getRHS() != 0)
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return State;
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SE = SIE->getLHS();
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Negated = SIE->getOpcode() == BO_EQ; // Equal to zero means negation
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Opc = getOpcode(SE);
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if (Opc != BO_EQ && Opc != BO_NE)
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return State;
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Comp = loadComparison(State, SE);
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if (!Comp)
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return State;
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}
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return processComparison(State, Comp->getLeft(), Comp->getRight(),
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(Comp->isEquality() == Assumption) != Negated);
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}
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// FIXME: Evaluation of these STL calls should be moved to StdCLibraryFunctions
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// checker (see patch r284960) or another similar checker for C++ STL
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// functions (e.g. StdCXXLibraryFunctions or StdCppLibraryFunctions).
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bool IteratorPastEndChecker::evalCall(const CallExpr *CE,
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CheckerContext &C) const {
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const FunctionDecl *FD = C.getCalleeDecl(CE);
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if (!FD)
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return false;
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ASTContext &Ctx = C.getASTContext();
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initIdentifiers(Ctx);
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if (FD->getKind() == Decl::Function) {
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if (FD->isInStdNamespace()) {
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if (FD->getIdentifier() == II_find) {
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return evalFind(C, CE);
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} else if (FD->getIdentifier() == II_find_end) {
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return evalFindEnd(C, CE);
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} else if (FD->getIdentifier() == II_find_first_of) {
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return evalFindFirstOf(C, CE);
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} else if (FD->getIdentifier() == II_find_if) {
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return evalFindIf(C, CE);
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} else if (FD->getIdentifier() == II_find_if) {
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return evalFindIf(C, CE);
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} else if (FD->getIdentifier() == II_find_if_not) {
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return evalFindIfNot(C, CE);
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} else if (FD->getIdentifier() == II_upper_bound) {
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return evalUpperBound(C, CE);
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} else if (FD->getIdentifier() == II_lower_bound) {
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return evalLowerBound(C, CE);
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} else if (FD->getIdentifier() == II_search) {
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return evalSearch(C, CE);
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} else if (FD->getIdentifier() == II_search_n) {
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return evalSearchN(C, CE);
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}
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}
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}
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return false;
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}
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void IteratorPastEndChecker::handleComparison(CheckerContext &C,
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const SVal &RetVal,
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const SVal &LVal,
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const SVal &RVal,
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OverloadedOperatorKind Op) const {
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// Record the operands and the operator of the comparison for the next
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// evalAssume, if the result is a symbolic expression. If it is a concrete
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// value (only one branch is possible), then transfer the state between
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// the operands according to the operator and the result
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auto State = C.getState();
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if (const auto *Condition = RetVal.getAsSymbolicExpression()) {
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const auto *LPos = getIteratorPosition(State, LVal);
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const auto *RPos = getIteratorPosition(State, RVal);
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if (!LPos && !RPos)
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return;
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State = saveComparison(State, Condition, LVal, RVal, Op == OO_EqualEqual);
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C.addTransition(State);
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} else if (const auto TruthVal = RetVal.getAs<nonloc::ConcreteInt>()) {
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if ((State = processComparison(
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State, getRegionOrSymbol(LVal), getRegionOrSymbol(RVal),
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(Op == OO_EqualEqual) == (TruthVal->getValue() != 0)))) {
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C.addTransition(State);
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} else {
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C.generateSink(State, C.getPredecessor());
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}
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}
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}
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void IteratorPastEndChecker::handleAccess(CheckerContext &C,
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const SVal &Val) const {
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auto State = C.getState();
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const auto *Pos = getIteratorPosition(State, Val);
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if (Pos && Pos->isOutofRange()) {
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auto *N = C.generateNonFatalErrorNode(State);
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if (!N) {
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return;
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}
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reportPastEndBug("Iterator accessed past its end.", Val, C, N);
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}
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}
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void IteratorPastEndChecker::handleDecrement(CheckerContext &C,
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const SVal &Val) const {
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auto State = C.getState();
|
|
const auto *Pos = getIteratorPosition(State, Val);
|
|
if (Pos && Pos->isOutofRange()) {
|
|
State = setIteratorPosition(State, Val, IteratorPosition::getInRange());
|
|
// FIXME: We could also check for iterators ahead of their beginnig in the
|
|
// future, but currently we do not care for such errors. We also
|
|
// assume that the iterator is not past its end by more then one
|
|
// position.
|
|
C.addTransition(State);
|
|
}
|
|
}
|
|
|
|
void IteratorPastEndChecker::handleEnd(CheckerContext &C,
|
|
const SVal &RetVal) const {
|
|
auto State = C.getState();
|
|
State = setIteratorPosition(State, RetVal, IteratorPosition::getOutofRange());
|
|
C.addTransition(State);
|
|
}
|
|
|
|
bool IteratorPastEndChecker::evalFind(CheckerContext &C,
|
|
const CallExpr *CE) const {
|
|
if (CE->getNumArgs() == 3 && isIteratorType(CE->getArg(0)->getType()) &&
|
|
isIteratorType(CE->getArg(1)->getType())) {
|
|
Find(C, CE);
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
bool IteratorPastEndChecker::evalFindEnd(CheckerContext &C,
|
|
const CallExpr *CE) const {
|
|
if ((CE->getNumArgs() == 4 || CE->getNumArgs() == 5) &&
|
|
isIteratorType(CE->getArg(0)->getType()) &&
|
|
isIteratorType(CE->getArg(1)->getType()) &&
|
|
isIteratorType(CE->getArg(2)->getType()) &&
|
|
isIteratorType(CE->getArg(3)->getType())) {
|
|
Find(C, CE);
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
bool IteratorPastEndChecker::evalFindFirstOf(CheckerContext &C,
|
|
const CallExpr *CE) const {
|
|
if ((CE->getNumArgs() == 4 || CE->getNumArgs() == 5) &&
|
|
isIteratorType(CE->getArg(0)->getType()) &&
|
|
isIteratorType(CE->getArg(1)->getType()) &&
|
|
isIteratorType(CE->getArg(2)->getType()) &&
|
|
isIteratorType(CE->getArg(3)->getType())) {
|
|
Find(C, CE);
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
bool IteratorPastEndChecker::evalFindIf(CheckerContext &C,
|
|
const CallExpr *CE) const {
|
|
if (CE->getNumArgs() == 3 && isIteratorType(CE->getArg(0)->getType()) &&
|
|
isIteratorType(CE->getArg(1)->getType())) {
|
|
Find(C, CE);
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
bool IteratorPastEndChecker::evalFindIfNot(CheckerContext &C,
|
|
const CallExpr *CE) const {
|
|
if (CE->getNumArgs() == 3 && isIteratorType(CE->getArg(0)->getType()) &&
|
|
isIteratorType(CE->getArg(1)->getType())) {
|
|
Find(C, CE);
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
bool IteratorPastEndChecker::evalLowerBound(CheckerContext &C,
|
|
const CallExpr *CE) const {
|
|
if ((CE->getNumArgs() == 3 || CE->getNumArgs() == 4) &&
|
|
isIteratorType(CE->getArg(0)->getType()) &&
|
|
isIteratorType(CE->getArg(1)->getType())) {
|
|
Find(C, CE);
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
bool IteratorPastEndChecker::evalUpperBound(CheckerContext &C,
|
|
const CallExpr *CE) const {
|
|
if ((CE->getNumArgs() == 3 || CE->getNumArgs() == 4) &&
|
|
isIteratorType(CE->getArg(0)->getType()) &&
|
|
isIteratorType(CE->getArg(1)->getType())) {
|
|
Find(C, CE);
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
bool IteratorPastEndChecker::evalSearch(CheckerContext &C,
|
|
const CallExpr *CE) const {
|
|
if ((CE->getNumArgs() == 4 || CE->getNumArgs() == 5) &&
|
|
isIteratorType(CE->getArg(0)->getType()) &&
|
|
isIteratorType(CE->getArg(1)->getType()) &&
|
|
isIteratorType(CE->getArg(2)->getType()) &&
|
|
isIteratorType(CE->getArg(3)->getType())) {
|
|
Find(C, CE);
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
bool IteratorPastEndChecker::evalSearchN(CheckerContext &C,
|
|
const CallExpr *CE) const {
|
|
if ((CE->getNumArgs() == 4 || CE->getNumArgs() == 5) &&
|
|
isIteratorType(CE->getArg(0)->getType()) &&
|
|
isIteratorType(CE->getArg(1)->getType())) {
|
|
Find(C, CE);
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
void IteratorPastEndChecker::Find(CheckerContext &C, const CallExpr *CE) const {
|
|
auto state = C.getState();
|
|
auto &svalBuilder = C.getSValBuilder();
|
|
const auto *LCtx = C.getLocationContext();
|
|
|
|
auto RetVal = svalBuilder.conjureSymbolVal(nullptr, CE, LCtx, C.blockCount());
|
|
auto SecondParam = state->getSVal(CE->getArg(1), LCtx);
|
|
|
|
auto stateFound = state->BindExpr(CE, LCtx, RetVal);
|
|
auto stateNotFound = state->BindExpr(CE, LCtx, SecondParam);
|
|
|
|
C.addTransition(stateFound);
|
|
C.addTransition(stateNotFound);
|
|
}
|
|
|
|
void IteratorPastEndChecker::reportPastEndBug(const StringRef &Message,
|
|
const SVal &Val,
|
|
CheckerContext &C,
|
|
ExplodedNode *ErrNode) const {
|
|
auto R = llvm::make_unique<BugReport>(*PastEndBugType, Message, ErrNode);
|
|
R->markInteresting(Val);
|
|
C.emitReport(std::move(R));
|
|
}
|
|
|
|
void IteratorPastEndChecker::initIdentifiers(ASTContext &Ctx) const {
|
|
INIT_ID(find);
|
|
INIT_ID(find_end);
|
|
INIT_ID(find_first_of);
|
|
INIT_ID(find_if);
|
|
INIT_ID(find_if_not);
|
|
INIT_ID(lower_bound);
|
|
INIT_ID(upper_bound);
|
|
INIT_ID(search);
|
|
INIT_ID(search_n);
|
|
}
|
|
|
|
namespace {
|
|
|
|
bool isIteratorType(const QualType &Type) {
|
|
if (Type->isPointerType())
|
|
return true;
|
|
|
|
const auto *CRD = Type->getUnqualifiedDesugaredType()->getAsCXXRecordDecl();
|
|
return isIterator(CRD);
|
|
}
|
|
|
|
bool isIterator(const CXXRecordDecl *CRD) {
|
|
if (!CRD)
|
|
return false;
|
|
|
|
const auto Name = CRD->getName();
|
|
if (!(Name.endswith_lower("iterator") || Name.endswith_lower("iter") ||
|
|
Name.endswith_lower("it")))
|
|
return false;
|
|
|
|
bool HasCopyCtor = false, HasCopyAssign = true, HasDtor = false,
|
|
HasPreIncrOp = false, HasPostIncrOp = false, HasDerefOp = false;
|
|
for (const auto *Method : CRD->methods()) {
|
|
if (const auto *Ctor = dyn_cast<CXXConstructorDecl>(Method)) {
|
|
if (Ctor->isCopyConstructor()) {
|
|
HasCopyCtor = !Ctor->isDeleted() && Ctor->getAccess() == AS_public;
|
|
}
|
|
continue;
|
|
}
|
|
if (const auto *Dtor = dyn_cast<CXXDestructorDecl>(Method)) {
|
|
HasDtor = !Dtor->isDeleted() && Dtor->getAccess() == AS_public;
|
|
continue;
|
|
}
|
|
if (Method->isCopyAssignmentOperator()) {
|
|
HasCopyAssign = !Method->isDeleted() && Method->getAccess() == AS_public;
|
|
continue;
|
|
}
|
|
if (!Method->isOverloadedOperator())
|
|
continue;
|
|
const auto OPK = Method->getOverloadedOperator();
|
|
if (OPK == OO_PlusPlus) {
|
|
HasPreIncrOp = HasPreIncrOp || (Method->getNumParams() == 0);
|
|
HasPostIncrOp = HasPostIncrOp || (Method->getNumParams() == 1);
|
|
continue;
|
|
}
|
|
if (OPK == OO_Star) {
|
|
HasDerefOp = (Method->getNumParams() == 0);
|
|
continue;
|
|
}
|
|
}
|
|
|
|
return HasCopyCtor && HasCopyAssign && HasDtor && HasPreIncrOp &&
|
|
HasPostIncrOp && HasDerefOp;
|
|
}
|
|
|
|
bool isEndCall(const FunctionDecl *Func) {
|
|
const auto *IdInfo = Func->getIdentifier();
|
|
if (!IdInfo)
|
|
return false;
|
|
return IdInfo->getName().endswith_lower("end");
|
|
}
|
|
|
|
bool isSimpleComparisonOperator(OverloadedOperatorKind OK) {
|
|
return OK == OO_EqualEqual || OK == OO_ExclaimEqual;
|
|
}
|
|
|
|
bool isAccessOperator(OverloadedOperatorKind OK) {
|
|
return OK == OO_Star || OK == OO_Arrow || OK == OO_ArrowStar ||
|
|
OK == OO_Plus || OK == OO_PlusEqual || OK == OO_PlusPlus ||
|
|
OK == OO_Subscript;
|
|
}
|
|
|
|
bool isDecrementOperator(OverloadedOperatorKind OK) {
|
|
return OK == OO_MinusEqual || OK == OO_MinusMinus;
|
|
}
|
|
|
|
BinaryOperator::Opcode getOpcode(const SymExpr *SE) {
|
|
if (const auto *BSE = dyn_cast<BinarySymExpr>(SE)) {
|
|
return BSE->getOpcode();
|
|
} else if (const auto *SC = dyn_cast<SymbolConjured>(SE)) {
|
|
const auto *COE = dyn_cast<CXXOperatorCallExpr>(SC->getStmt());
|
|
if (!COE)
|
|
return BO_Comma; // Extremal value, neither EQ nor NE
|
|
if (COE->getOperator() == OO_EqualEqual) {
|
|
return BO_EQ;
|
|
} else if (COE->getOperator() == OO_ExclaimEqual) {
|
|
return BO_NE;
|
|
}
|
|
return BO_Comma; // Extremal value, neither EQ nor NE
|
|
}
|
|
return BO_Comma; // Extremal value, neither EQ nor NE
|
|
}
|
|
|
|
const RegionOrSymbol getRegionOrSymbol(const SVal &Val) {
|
|
if (const auto Reg = Val.getAsRegion()) {
|
|
return Reg;
|
|
} else if (const auto Sym = Val.getAsSymbol()) {
|
|
return Sym;
|
|
} else if (const auto LCVal = Val.getAs<nonloc::LazyCompoundVal>()) {
|
|
return LCVal->getRegion();
|
|
}
|
|
return RegionOrSymbol();
|
|
}
|
|
|
|
const ProgramStateRef processComparison(ProgramStateRef State,
|
|
RegionOrSymbol LVal,
|
|
RegionOrSymbol RVal, bool Equal) {
|
|
const auto *LPos = getIteratorPosition(State, LVal);
|
|
const auto *RPos = getIteratorPosition(State, RVal);
|
|
if (LPos && !RPos) {
|
|
State = adjustIteratorPosition(State, RVal, *LPos, Equal);
|
|
} else if (!LPos && RPos) {
|
|
State = adjustIteratorPosition(State, LVal, *RPos, Equal);
|
|
} else if (LPos && RPos) {
|
|
if (contradictingIteratorPositions(*LPos, *RPos, Equal)) {
|
|
return nullptr;
|
|
}
|
|
}
|
|
return State;
|
|
}
|
|
|
|
const ProgramStateRef saveComparison(ProgramStateRef State,
|
|
const SymExpr *Condition, const SVal &LVal,
|
|
const SVal &RVal, bool Eq) {
|
|
const auto Left = getRegionOrSymbol(LVal);
|
|
const auto Right = getRegionOrSymbol(RVal);
|
|
if (!Left || !Right)
|
|
return State;
|
|
return State->set<IteratorComparisonMap>(Condition,
|
|
IteratorComparison(Left, Right, Eq));
|
|
}
|
|
|
|
const IteratorComparison *loadComparison(ProgramStateRef State,
|
|
const SymExpr *Condition) {
|
|
return State->get<IteratorComparisonMap>(Condition);
|
|
}
|
|
|
|
const IteratorPosition *getIteratorPosition(ProgramStateRef State,
|
|
const SVal &Val) {
|
|
if (const auto Reg = Val.getAsRegion()) {
|
|
return State->get<IteratorRegionMap>(Reg);
|
|
} else if (const auto Sym = Val.getAsSymbol()) {
|
|
return State->get<IteratorSymbolMap>(Sym);
|
|
} else if (const auto LCVal = Val.getAs<nonloc::LazyCompoundVal>()) {
|
|
return State->get<IteratorRegionMap>(LCVal->getRegion());
|
|
}
|
|
return nullptr;
|
|
}
|
|
|
|
const IteratorPosition *getIteratorPosition(ProgramStateRef State,
|
|
RegionOrSymbol RegOrSym) {
|
|
if (RegOrSym.is<const MemRegion *>()) {
|
|
return State->get<IteratorRegionMap>(RegOrSym.get<const MemRegion *>());
|
|
} else if (RegOrSym.is<SymbolRef>()) {
|
|
return State->get<IteratorSymbolMap>(RegOrSym.get<SymbolRef>());
|
|
}
|
|
return nullptr;
|
|
}
|
|
|
|
ProgramStateRef setIteratorPosition(ProgramStateRef State, const SVal &Val,
|
|
IteratorPosition Pos) {
|
|
if (const auto Reg = Val.getAsRegion()) {
|
|
return State->set<IteratorRegionMap>(Reg, Pos);
|
|
} else if (const auto Sym = Val.getAsSymbol()) {
|
|
return State->set<IteratorSymbolMap>(Sym, Pos);
|
|
} else if (const auto LCVal = Val.getAs<nonloc::LazyCompoundVal>()) {
|
|
return State->set<IteratorRegionMap>(LCVal->getRegion(), Pos);
|
|
}
|
|
return nullptr;
|
|
}
|
|
|
|
ProgramStateRef setIteratorPosition(ProgramStateRef State,
|
|
RegionOrSymbol RegOrSym,
|
|
IteratorPosition Pos) {
|
|
if (RegOrSym.is<const MemRegion *>()) {
|
|
return State->set<IteratorRegionMap>(RegOrSym.get<const MemRegion *>(),
|
|
Pos);
|
|
} else if (RegOrSym.is<SymbolRef>()) {
|
|
return State->set<IteratorSymbolMap>(RegOrSym.get<SymbolRef>(), Pos);
|
|
}
|
|
return nullptr;
|
|
}
|
|
|
|
ProgramStateRef adjustIteratorPosition(ProgramStateRef State,
|
|
RegionOrSymbol RegOrSym,
|
|
IteratorPosition Pos, bool Equal) {
|
|
|
|
if ((Pos.isInRange() && Equal) || (Pos.isOutofRange() && !Equal)) {
|
|
return setIteratorPosition(State, RegOrSym, IteratorPosition::getInRange());
|
|
} else if (Pos.isOutofRange() && Equal) {
|
|
return setIteratorPosition(State, RegOrSym,
|
|
IteratorPosition::getOutofRange());
|
|
} else {
|
|
return State;
|
|
}
|
|
}
|
|
|
|
bool contradictingIteratorPositions(IteratorPosition Pos1,
|
|
IteratorPosition Pos2, bool Equal) {
|
|
return ((Pos1 != Pos2) && Equal) ||
|
|
((Pos1.isOutofRange() && Pos2.isOutofRange()) && !Equal);
|
|
}
|
|
}
|
|
|
|
void ento::registerIteratorPastEndChecker(CheckerManager &Mgr) {
|
|
Mgr.registerChecker<IteratorPastEndChecker>();
|
|
}
|