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1084 lines
40 KiB
1084 lines
40 KiB
//===-- ContainerModeling.cpp -------------------------------------*- C++ -*--//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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//
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// Defines a modeling-checker for modeling STL container-like containers.
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//
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//===----------------------------------------------------------------------===//
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#include "clang/StaticAnalyzer/Checkers/BuiltinCheckerRegistration.h"
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#include "clang/AST/DeclTemplate.h"
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#include "clang/Driver/DriverDiagnostic.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 "clang/StaticAnalyzer/Core/PathSensitive/DynamicType.h"
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#include "Iterator.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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using namespace iterator;
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namespace {
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class ContainerModeling
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: public Checker<check::PostCall, check::LiveSymbols, check::DeadSymbols> {
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void handleBegin(CheckerContext &C, const Expr *CE, SVal RetVal,
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SVal Cont) const;
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void handleEnd(CheckerContext &C, const Expr *CE, SVal RetVal,
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SVal Cont) const;
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void handleAssignment(CheckerContext &C, SVal Cont, const Expr *CE = nullptr,
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SVal OldCont = UndefinedVal()) const;
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void handleAssign(CheckerContext &C, SVal Cont, const Expr *ContE) const;
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void handleClear(CheckerContext &C, SVal Cont, const Expr *ContE) const;
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void handlePushBack(CheckerContext &C, SVal Cont, const Expr *ContE) const;
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void handlePopBack(CheckerContext &C, SVal Cont, const Expr *ContE) const;
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void handlePushFront(CheckerContext &C, SVal Cont, const Expr *ContE) const;
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void handlePopFront(CheckerContext &C, SVal Cont, const Expr *ContE) const;
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void handleInsert(CheckerContext &C, SVal Cont, SVal Iter) const;
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void handleErase(CheckerContext &C, SVal Cont, SVal Iter) const;
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void handleErase(CheckerContext &C, SVal Cont, SVal Iter1, SVal Iter2) const;
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void handleEraseAfter(CheckerContext &C, SVal Cont, SVal Iter) const;
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void handleEraseAfter(CheckerContext &C, SVal Cont, SVal Iter1,
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SVal Iter2) const;
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const NoteTag *getChangeTag(CheckerContext &C, StringRef Text,
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const MemRegion *ContReg,
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const Expr *ContE) const;
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void printState(raw_ostream &Out, ProgramStateRef State, const char *NL,
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const char *Sep) const override;
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public:
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ContainerModeling() = default;
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void checkPostCall(const CallEvent &Call, CheckerContext &C) const;
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void checkLiveSymbols(ProgramStateRef State, SymbolReaper &SR) const;
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void checkDeadSymbols(SymbolReaper &SR, CheckerContext &C) const;
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using NoItParamFn = void (ContainerModeling::*)(CheckerContext &, SVal,
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const Expr *) const;
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using OneItParamFn = void (ContainerModeling::*)(CheckerContext &, SVal,
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SVal) const;
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using TwoItParamFn = void (ContainerModeling::*)(CheckerContext &, SVal, SVal,
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SVal) const;
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CallDescriptionMap<NoItParamFn> NoIterParamFunctions = {
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{{0, "clear", 0},
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&ContainerModeling::handleClear},
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{{0, "assign", 2},
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&ContainerModeling::handleAssign},
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{{0, "push_back", 1},
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&ContainerModeling::handlePushBack},
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{{0, "emplace_back", 1},
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&ContainerModeling::handlePushBack},
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{{0, "pop_back", 0},
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&ContainerModeling::handlePopBack},
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{{0, "push_front", 1},
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&ContainerModeling::handlePushFront},
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{{0, "emplace_front", 1},
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&ContainerModeling::handlePushFront},
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{{0, "pop_front", 0},
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&ContainerModeling::handlePopFront},
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};
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CallDescriptionMap<OneItParamFn> OneIterParamFunctions = {
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{{0, "insert", 2},
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&ContainerModeling::handleInsert},
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{{0, "emplace", 2},
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&ContainerModeling::handleInsert},
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{{0, "erase", 1},
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&ContainerModeling::handleErase},
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{{0, "erase_after", 1},
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&ContainerModeling::handleEraseAfter},
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};
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CallDescriptionMap<TwoItParamFn> TwoIterParamFunctions = {
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{{0, "erase", 2},
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&ContainerModeling::handleErase},
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{{0, "erase_after", 2},
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&ContainerModeling::handleEraseAfter},
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};
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};
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bool isBeginCall(const FunctionDecl *Func);
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bool isEndCall(const FunctionDecl *Func);
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bool hasSubscriptOperator(ProgramStateRef State, const MemRegion *Reg);
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bool frontModifiable(ProgramStateRef State, const MemRegion *Reg);
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bool backModifiable(ProgramStateRef State, const MemRegion *Reg);
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SymbolRef getContainerBegin(ProgramStateRef State, const MemRegion *Cont);
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SymbolRef getContainerEnd(ProgramStateRef State, const MemRegion *Cont);
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ProgramStateRef createContainerBegin(ProgramStateRef State,
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const MemRegion *Cont, const Expr *E,
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QualType T, const LocationContext *LCtx,
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unsigned BlockCount);
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ProgramStateRef createContainerEnd(ProgramStateRef State, const MemRegion *Cont,
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const Expr *E, QualType T,
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const LocationContext *LCtx,
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unsigned BlockCount);
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ProgramStateRef setContainerData(ProgramStateRef State, const MemRegion *Cont,
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const ContainerData &CData);
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ProgramStateRef invalidateAllIteratorPositions(ProgramStateRef State,
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const MemRegion *Cont);
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ProgramStateRef
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invalidateAllIteratorPositionsExcept(ProgramStateRef State,
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const MemRegion *Cont, SymbolRef Offset,
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BinaryOperator::Opcode Opc);
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ProgramStateRef invalidateIteratorPositions(ProgramStateRef State,
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SymbolRef Offset,
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BinaryOperator::Opcode Opc);
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ProgramStateRef invalidateIteratorPositions(ProgramStateRef State,
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SymbolRef Offset1,
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BinaryOperator::Opcode Opc1,
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SymbolRef Offset2,
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BinaryOperator::Opcode Opc2);
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ProgramStateRef reassignAllIteratorPositions(ProgramStateRef State,
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const MemRegion *Cont,
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const MemRegion *NewCont);
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ProgramStateRef reassignAllIteratorPositionsUnless(ProgramStateRef State,
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const MemRegion *Cont,
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const MemRegion *NewCont,
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SymbolRef Offset,
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BinaryOperator::Opcode Opc);
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ProgramStateRef rebaseSymbolInIteratorPositionsIf(
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ProgramStateRef State, SValBuilder &SVB, SymbolRef OldSym,
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SymbolRef NewSym, SymbolRef CondSym, BinaryOperator::Opcode Opc);
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SymbolRef rebaseSymbol(ProgramStateRef State, SValBuilder &SVB, SymbolRef Expr,
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SymbolRef OldSym, SymbolRef NewSym);
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bool hasLiveIterators(ProgramStateRef State, const MemRegion *Cont);
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} // namespace
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void ContainerModeling::checkPostCall(const CallEvent &Call,
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CheckerContext &C) const {
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const auto *Func = dyn_cast_or_null<FunctionDecl>(Call.getDecl());
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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 (Op == OO_Equal) {
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// Overloaded 'operator=' must be a non-static member function.
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const auto *InstCall = cast<CXXInstanceCall>(&Call);
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if (cast<CXXMethodDecl>(Func)->isMoveAssignmentOperator()) {
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handleAssignment(C, InstCall->getCXXThisVal(), Call.getOriginExpr(),
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Call.getArgSVal(0));
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return;
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}
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handleAssignment(C, InstCall->getCXXThisVal());
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return;
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}
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} else {
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if (const auto *InstCall = dyn_cast<CXXInstanceCall>(&Call)) {
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const NoItParamFn *Handler0 = NoIterParamFunctions.lookup(Call);
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if (Handler0) {
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(this->**Handler0)(C, InstCall->getCXXThisVal(),
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InstCall->getCXXThisExpr());
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return;
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}
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const OneItParamFn *Handler1 = OneIterParamFunctions.lookup(Call);
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if (Handler1) {
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(this->**Handler1)(C, InstCall->getCXXThisVal(), Call.getArgSVal(0));
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return;
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}
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const TwoItParamFn *Handler2 = TwoIterParamFunctions.lookup(Call);
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if (Handler2) {
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(this->**Handler2)(C, InstCall->getCXXThisVal(), Call.getArgSVal(0),
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Call.getArgSVal(1));
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return;
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}
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const auto *OrigExpr = Call.getOriginExpr();
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if (!OrigExpr)
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return;
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if (isBeginCall(Func)) {
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handleBegin(C, OrigExpr, Call.getReturnValue(),
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InstCall->getCXXThisVal());
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return;
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}
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if (isEndCall(Func)) {
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handleEnd(C, OrigExpr, Call.getReturnValue(),
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InstCall->getCXXThisVal());
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return;
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}
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}
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}
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}
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void ContainerModeling::checkLiveSymbols(ProgramStateRef State,
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SymbolReaper &SR) const {
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// Keep symbolic expressions of container begins and ends alive
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auto ContMap = State->get<ContainerMap>();
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for (const auto &Cont : ContMap) {
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const auto CData = Cont.second;
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if (CData.getBegin()) {
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SR.markLive(CData.getBegin());
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if(const auto *SIE = dyn_cast<SymIntExpr>(CData.getBegin()))
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SR.markLive(SIE->getLHS());
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}
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if (CData.getEnd()) {
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SR.markLive(CData.getEnd());
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if(const auto *SIE = dyn_cast<SymIntExpr>(CData.getEnd()))
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SR.markLive(SIE->getLHS());
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}
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}
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}
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void ContainerModeling::checkDeadSymbols(SymbolReaper &SR,
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CheckerContext &C) const {
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// Cleanup
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auto State = C.getState();
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auto ContMap = State->get<ContainerMap>();
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for (const auto &Cont : ContMap) {
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if (!SR.isLiveRegion(Cont.first)) {
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// We must keep the container data while it has live iterators to be able
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// to compare them to the begin and the end of the container.
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if (!hasLiveIterators(State, Cont.first)) {
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State = State->remove<ContainerMap>(Cont.first);
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}
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}
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}
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C.addTransition(State);
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}
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void ContainerModeling::handleBegin(CheckerContext &C, const Expr *CE,
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SVal RetVal, SVal Cont) const {
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const auto *ContReg = Cont.getAsRegion();
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if (!ContReg)
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return;
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ContReg = ContReg->getMostDerivedObjectRegion();
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// If the container already has a begin symbol then use it. Otherwise first
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// create a new one.
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auto State = C.getState();
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auto BeginSym = getContainerBegin(State, ContReg);
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if (!BeginSym) {
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State = createContainerBegin(State, ContReg, CE, C.getASTContext().LongTy,
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C.getLocationContext(), C.blockCount());
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BeginSym = getContainerBegin(State, ContReg);
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}
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State = setIteratorPosition(State, RetVal,
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IteratorPosition::getPosition(ContReg, BeginSym));
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C.addTransition(State);
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}
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void ContainerModeling::handleEnd(CheckerContext &C, const Expr *CE,
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SVal RetVal, SVal Cont) const {
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const auto *ContReg = Cont.getAsRegion();
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if (!ContReg)
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return;
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ContReg = ContReg->getMostDerivedObjectRegion();
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// If the container already has an end symbol then use it. Otherwise first
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// create a new one.
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auto State = C.getState();
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auto EndSym = getContainerEnd(State, ContReg);
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if (!EndSym) {
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State = createContainerEnd(State, ContReg, CE, C.getASTContext().LongTy,
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C.getLocationContext(), C.blockCount());
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EndSym = getContainerEnd(State, ContReg);
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}
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State = setIteratorPosition(State, RetVal,
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IteratorPosition::getPosition(ContReg, EndSym));
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C.addTransition(State);
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}
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void ContainerModeling::handleAssignment(CheckerContext &C, SVal Cont,
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const Expr *CE, SVal OldCont) const {
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const auto *ContReg = Cont.getAsRegion();
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if (!ContReg)
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return;
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ContReg = ContReg->getMostDerivedObjectRegion();
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// Assignment of a new value to a container always invalidates all its
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// iterators
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auto State = C.getState();
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const auto CData = getContainerData(State, ContReg);
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if (CData) {
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State = invalidateAllIteratorPositions(State, ContReg);
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}
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// In case of move, iterators of the old container (except the past-end
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// iterators) remain valid but refer to the new container
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if (!OldCont.isUndef()) {
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const auto *OldContReg = OldCont.getAsRegion();
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if (OldContReg) {
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OldContReg = OldContReg->getMostDerivedObjectRegion();
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const auto OldCData = getContainerData(State, OldContReg);
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if (OldCData) {
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if (const auto OldEndSym = OldCData->getEnd()) {
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// If we already assigned an "end" symbol to the old container, then
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// first reassign all iterator positions to the new container which
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// are not past the container (thus not greater or equal to the
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// current "end" symbol).
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State = reassignAllIteratorPositionsUnless(State, OldContReg, ContReg,
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OldEndSym, BO_GE);
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auto &SymMgr = C.getSymbolManager();
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auto &SVB = C.getSValBuilder();
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// Then generate and assign a new "end" symbol for the new container.
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auto NewEndSym =
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SymMgr.conjureSymbol(CE, C.getLocationContext(),
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C.getASTContext().LongTy, C.blockCount());
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State = assumeNoOverflow(State, NewEndSym, 4);
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if (CData) {
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State = setContainerData(State, ContReg, CData->newEnd(NewEndSym));
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} else {
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State = setContainerData(State, ContReg,
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ContainerData::fromEnd(NewEndSym));
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}
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// Finally, replace the old "end" symbol in the already reassigned
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// iterator positions with the new "end" symbol.
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State = rebaseSymbolInIteratorPositionsIf(
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State, SVB, OldEndSym, NewEndSym, OldEndSym, BO_LT);
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} else {
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// There was no "end" symbol assigned yet to the old container,
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// so reassign all iterator positions to the new container.
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State = reassignAllIteratorPositions(State, OldContReg, ContReg);
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}
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if (const auto OldBeginSym = OldCData->getBegin()) {
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// If we already assigned a "begin" symbol to the old container, then
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// assign it to the new container and remove it from the old one.
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if (CData) {
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State =
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setContainerData(State, ContReg, CData->newBegin(OldBeginSym));
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} else {
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State = setContainerData(State, ContReg,
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ContainerData::fromBegin(OldBeginSym));
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}
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State =
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setContainerData(State, OldContReg, OldCData->newBegin(nullptr));
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}
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} else {
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// There was neither "begin" nor "end" symbol assigned yet to the old
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// container, so reassign all iterator positions to the new container.
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State = reassignAllIteratorPositions(State, OldContReg, ContReg);
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}
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}
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}
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C.addTransition(State);
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}
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void ContainerModeling::handleAssign(CheckerContext &C, SVal Cont,
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const Expr *ContE) const {
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const auto *ContReg = Cont.getAsRegion();
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if (!ContReg)
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return;
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ContReg = ContReg->getMostDerivedObjectRegion();
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// The assign() operation invalidates all the iterators
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auto State = C.getState();
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State = invalidateAllIteratorPositions(State, ContReg);
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C.addTransition(State);
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}
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void ContainerModeling::handleClear(CheckerContext &C, SVal Cont,
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const Expr *ContE) const {
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const auto *ContReg = Cont.getAsRegion();
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if (!ContReg)
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return;
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ContReg = ContReg->getMostDerivedObjectRegion();
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// The clear() operation invalidates all the iterators, except the past-end
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// iterators of list-like containers
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auto State = C.getState();
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if (!hasSubscriptOperator(State, ContReg) ||
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!backModifiable(State, ContReg)) {
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const auto CData = getContainerData(State, ContReg);
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if (CData) {
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if (const auto EndSym = CData->getEnd()) {
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State =
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invalidateAllIteratorPositionsExcept(State, ContReg, EndSym, BO_GE);
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C.addTransition(State);
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return;
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}
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}
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}
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const NoteTag *ChangeTag =
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getChangeTag(C, "became empty", ContReg, ContE);
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State = invalidateAllIteratorPositions(State, ContReg);
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C.addTransition(State, ChangeTag);
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}
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void ContainerModeling::handlePushBack(CheckerContext &C, SVal Cont,
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const Expr *ContE) const {
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const auto *ContReg = Cont.getAsRegion();
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if (!ContReg)
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return;
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ContReg = ContReg->getMostDerivedObjectRegion();
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// For deque-like containers invalidate all iterator positions
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auto State = C.getState();
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if (hasSubscriptOperator(State, ContReg) && frontModifiable(State, ContReg)) {
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State = invalidateAllIteratorPositions(State, ContReg);
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C.addTransition(State);
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return;
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}
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const auto CData = getContainerData(State, ContReg);
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if (!CData)
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return;
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// For vector-like containers invalidate the past-end iterator positions
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if (const auto EndSym = CData->getEnd()) {
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if (hasSubscriptOperator(State, ContReg)) {
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State = invalidateIteratorPositions(State, EndSym, BO_GE);
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}
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auto &SymMgr = C.getSymbolManager();
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auto &BVF = SymMgr.getBasicVals();
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auto &SVB = C.getSValBuilder();
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const auto newEndSym =
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SVB.evalBinOp(State, BO_Add,
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nonloc::SymbolVal(EndSym),
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nonloc::ConcreteInt(BVF.getValue(llvm::APSInt::get(1))),
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SymMgr.getType(EndSym)).getAsSymbol();
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const NoteTag *ChangeTag =
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getChangeTag(C, "extended to the back by 1 position", ContReg, ContE);
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State = setContainerData(State, ContReg, CData->newEnd(newEndSym));
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C.addTransition(State, ChangeTag);
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}
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}
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void ContainerModeling::handlePopBack(CheckerContext &C, SVal Cont,
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const Expr *ContE) const {
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const auto *ContReg = Cont.getAsRegion();
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if (!ContReg)
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return;
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ContReg = ContReg->getMostDerivedObjectRegion();
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auto State = C.getState();
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const auto CData = getContainerData(State, ContReg);
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if (!CData)
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return;
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if (const auto EndSym = CData->getEnd()) {
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auto &SymMgr = C.getSymbolManager();
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auto &BVF = SymMgr.getBasicVals();
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auto &SVB = C.getSValBuilder();
|
|
const auto BackSym =
|
|
SVB.evalBinOp(State, BO_Sub,
|
|
nonloc::SymbolVal(EndSym),
|
|
nonloc::ConcreteInt(BVF.getValue(llvm::APSInt::get(1))),
|
|
SymMgr.getType(EndSym)).getAsSymbol();
|
|
const NoteTag *ChangeTag =
|
|
getChangeTag(C, "shrank from the back by 1 position", ContReg, ContE);
|
|
// For vector-like and deque-like containers invalidate the last and the
|
|
// past-end iterator positions. For list-like containers only invalidate
|
|
// the last position
|
|
if (hasSubscriptOperator(State, ContReg) &&
|
|
backModifiable(State, ContReg)) {
|
|
State = invalidateIteratorPositions(State, BackSym, BO_GE);
|
|
State = setContainerData(State, ContReg, CData->newEnd(nullptr));
|
|
} else {
|
|
State = invalidateIteratorPositions(State, BackSym, BO_EQ);
|
|
}
|
|
auto newEndSym = BackSym;
|
|
State = setContainerData(State, ContReg, CData->newEnd(newEndSym));
|
|
C.addTransition(State, ChangeTag);
|
|
}
|
|
}
|
|
|
|
void ContainerModeling::handlePushFront(CheckerContext &C, SVal Cont,
|
|
const Expr *ContE) const {
|
|
const auto *ContReg = Cont.getAsRegion();
|
|
if (!ContReg)
|
|
return;
|
|
|
|
ContReg = ContReg->getMostDerivedObjectRegion();
|
|
|
|
// For deque-like containers invalidate all iterator positions
|
|
auto State = C.getState();
|
|
if (hasSubscriptOperator(State, ContReg)) {
|
|
State = invalidateAllIteratorPositions(State, ContReg);
|
|
C.addTransition(State);
|
|
} else {
|
|
const auto CData = getContainerData(State, ContReg);
|
|
if (!CData)
|
|
return;
|
|
|
|
if (const auto BeginSym = CData->getBegin()) {
|
|
auto &SymMgr = C.getSymbolManager();
|
|
auto &BVF = SymMgr.getBasicVals();
|
|
auto &SVB = C.getSValBuilder();
|
|
const auto newBeginSym =
|
|
SVB.evalBinOp(State, BO_Sub,
|
|
nonloc::SymbolVal(BeginSym),
|
|
nonloc::ConcreteInt(BVF.getValue(llvm::APSInt::get(1))),
|
|
SymMgr.getType(BeginSym)).getAsSymbol();
|
|
const NoteTag *ChangeTag =
|
|
getChangeTag(C, "extended to the front by 1 position", ContReg, ContE);
|
|
State = setContainerData(State, ContReg, CData->newBegin(newBeginSym));
|
|
C.addTransition(State, ChangeTag);
|
|
}
|
|
}
|
|
}
|
|
|
|
void ContainerModeling::handlePopFront(CheckerContext &C, SVal Cont,
|
|
const Expr *ContE) const {
|
|
const auto *ContReg = Cont.getAsRegion();
|
|
if (!ContReg)
|
|
return;
|
|
|
|
ContReg = ContReg->getMostDerivedObjectRegion();
|
|
|
|
auto State = C.getState();
|
|
const auto CData = getContainerData(State, ContReg);
|
|
if (!CData)
|
|
return;
|
|
|
|
// For deque-like containers invalidate all iterator positions. For list-like
|
|
// iterators only invalidate the first position
|
|
if (const auto BeginSym = CData->getBegin()) {
|
|
if (hasSubscriptOperator(State, ContReg)) {
|
|
State = invalidateIteratorPositions(State, BeginSym, BO_LE);
|
|
} else {
|
|
State = invalidateIteratorPositions(State, BeginSym, BO_EQ);
|
|
}
|
|
auto &SymMgr = C.getSymbolManager();
|
|
auto &BVF = SymMgr.getBasicVals();
|
|
auto &SVB = C.getSValBuilder();
|
|
const auto newBeginSym =
|
|
SVB.evalBinOp(State, BO_Add,
|
|
nonloc::SymbolVal(BeginSym),
|
|
nonloc::ConcreteInt(BVF.getValue(llvm::APSInt::get(1))),
|
|
SymMgr.getType(BeginSym)).getAsSymbol();
|
|
const NoteTag *ChangeTag =
|
|
getChangeTag(C, "shrank from the front by 1 position", ContReg, ContE);
|
|
State = setContainerData(State, ContReg, CData->newBegin(newBeginSym));
|
|
C.addTransition(State, ChangeTag);
|
|
}
|
|
}
|
|
|
|
void ContainerModeling::handleInsert(CheckerContext &C, SVal Cont,
|
|
SVal Iter) const {
|
|
const auto *ContReg = Cont.getAsRegion();
|
|
if (!ContReg)
|
|
return;
|
|
|
|
ContReg = ContReg->getMostDerivedObjectRegion();
|
|
|
|
auto State = C.getState();
|
|
const auto *Pos = getIteratorPosition(State, Iter);
|
|
if (!Pos)
|
|
return;
|
|
|
|
// For deque-like containers invalidate all iterator positions. For
|
|
// vector-like containers invalidate iterator positions after the insertion.
|
|
if (hasSubscriptOperator(State, ContReg) && backModifiable(State, ContReg)) {
|
|
if (frontModifiable(State, ContReg)) {
|
|
State = invalidateAllIteratorPositions(State, ContReg);
|
|
} else {
|
|
State = invalidateIteratorPositions(State, Pos->getOffset(), BO_GE);
|
|
}
|
|
if (const auto *CData = getContainerData(State, ContReg)) {
|
|
if (const auto EndSym = CData->getEnd()) {
|
|
State = invalidateIteratorPositions(State, EndSym, BO_GE);
|
|
State = setContainerData(State, ContReg, CData->newEnd(nullptr));
|
|
}
|
|
}
|
|
C.addTransition(State);
|
|
}
|
|
}
|
|
|
|
void ContainerModeling::handleErase(CheckerContext &C, SVal Cont,
|
|
SVal Iter) const {
|
|
const auto *ContReg = Cont.getAsRegion();
|
|
if (!ContReg)
|
|
return;
|
|
|
|
ContReg = ContReg->getMostDerivedObjectRegion();
|
|
|
|
auto State = C.getState();
|
|
const auto *Pos = getIteratorPosition(State, Iter);
|
|
if (!Pos)
|
|
return;
|
|
|
|
// For deque-like containers invalidate all iterator positions. For
|
|
// vector-like containers invalidate iterator positions at and after the
|
|
// deletion. For list-like containers only invalidate the deleted position.
|
|
if (hasSubscriptOperator(State, ContReg) && backModifiable(State, ContReg)) {
|
|
if (frontModifiable(State, ContReg)) {
|
|
State = invalidateAllIteratorPositions(State, ContReg);
|
|
} else {
|
|
State = invalidateIteratorPositions(State, Pos->getOffset(), BO_GE);
|
|
}
|
|
if (const auto *CData = getContainerData(State, ContReg)) {
|
|
if (const auto EndSym = CData->getEnd()) {
|
|
State = invalidateIteratorPositions(State, EndSym, BO_GE);
|
|
State = setContainerData(State, ContReg, CData->newEnd(nullptr));
|
|
}
|
|
}
|
|
} else {
|
|
State = invalidateIteratorPositions(State, Pos->getOffset(), BO_EQ);
|
|
}
|
|
C.addTransition(State);
|
|
}
|
|
|
|
void ContainerModeling::handleErase(CheckerContext &C, SVal Cont, SVal Iter1,
|
|
SVal Iter2) const {
|
|
const auto *ContReg = Cont.getAsRegion();
|
|
if (!ContReg)
|
|
return;
|
|
|
|
ContReg = ContReg->getMostDerivedObjectRegion();
|
|
auto State = C.getState();
|
|
const auto *Pos1 = getIteratorPosition(State, Iter1);
|
|
const auto *Pos2 = getIteratorPosition(State, Iter2);
|
|
if (!Pos1 || !Pos2)
|
|
return;
|
|
|
|
// For deque-like containers invalidate all iterator positions. For
|
|
// vector-like containers invalidate iterator positions at and after the
|
|
// deletion range. For list-like containers only invalidate the deleted
|
|
// position range [first..last].
|
|
if (hasSubscriptOperator(State, ContReg) && backModifiable(State, ContReg)) {
|
|
if (frontModifiable(State, ContReg)) {
|
|
State = invalidateAllIteratorPositions(State, ContReg);
|
|
} else {
|
|
State = invalidateIteratorPositions(State, Pos1->getOffset(), BO_GE);
|
|
}
|
|
if (const auto *CData = getContainerData(State, ContReg)) {
|
|
if (const auto EndSym = CData->getEnd()) {
|
|
State = invalidateIteratorPositions(State, EndSym, BO_GE);
|
|
State = setContainerData(State, ContReg, CData->newEnd(nullptr));
|
|
}
|
|
}
|
|
} else {
|
|
State = invalidateIteratorPositions(State, Pos1->getOffset(), BO_GE,
|
|
Pos2->getOffset(), BO_LT);
|
|
}
|
|
C.addTransition(State);
|
|
}
|
|
|
|
void ContainerModeling::handleEraseAfter(CheckerContext &C, SVal Cont,
|
|
SVal Iter) const {
|
|
auto State = C.getState();
|
|
const auto *Pos = getIteratorPosition(State, Iter);
|
|
if (!Pos)
|
|
return;
|
|
|
|
// Invalidate the deleted iterator position, which is the position of the
|
|
// parameter plus one.
|
|
auto &SymMgr = C.getSymbolManager();
|
|
auto &BVF = SymMgr.getBasicVals();
|
|
auto &SVB = C.getSValBuilder();
|
|
const auto NextSym =
|
|
SVB.evalBinOp(State, BO_Add,
|
|
nonloc::SymbolVal(Pos->getOffset()),
|
|
nonloc::ConcreteInt(BVF.getValue(llvm::APSInt::get(1))),
|
|
SymMgr.getType(Pos->getOffset())).getAsSymbol();
|
|
State = invalidateIteratorPositions(State, NextSym, BO_EQ);
|
|
C.addTransition(State);
|
|
}
|
|
|
|
void ContainerModeling::handleEraseAfter(CheckerContext &C, SVal Cont,
|
|
SVal Iter1, SVal Iter2) const {
|
|
auto State = C.getState();
|
|
const auto *Pos1 = getIteratorPosition(State, Iter1);
|
|
const auto *Pos2 = getIteratorPosition(State, Iter2);
|
|
if (!Pos1 || !Pos2)
|
|
return;
|
|
|
|
// Invalidate the deleted iterator position range (first..last)
|
|
State = invalidateIteratorPositions(State, Pos1->getOffset(), BO_GT,
|
|
Pos2->getOffset(), BO_LT);
|
|
C.addTransition(State);
|
|
}
|
|
|
|
const NoteTag *ContainerModeling::getChangeTag(CheckerContext &C,
|
|
StringRef Text,
|
|
const MemRegion *ContReg,
|
|
const Expr *ContE) const {
|
|
StringRef Name;
|
|
// First try to get the name of the variable from the region
|
|
if (const auto *DR = dyn_cast<DeclRegion>(ContReg)) {
|
|
Name = DR->getDecl()->getName();
|
|
// If the region is not a `DeclRegion` then use the expression instead
|
|
} else if (const auto *DRE =
|
|
dyn_cast<DeclRefExpr>(ContE->IgnoreParenCasts())) {
|
|
Name = DRE->getDecl()->getName();
|
|
}
|
|
|
|
return C.getNoteTag(
|
|
[Text, Name, ContReg](PathSensitiveBugReport &BR) -> std::string {
|
|
if (!BR.isInteresting(ContReg))
|
|
return "";
|
|
|
|
SmallString<256> Msg;
|
|
llvm::raw_svector_ostream Out(Msg);
|
|
Out << "Container " << (!Name.empty() ? ("'" + Name.str() + "' ") : "" )
|
|
<< Text;
|
|
return std::string(Out.str());
|
|
});
|
|
}
|
|
|
|
void ContainerModeling::printState(raw_ostream &Out, ProgramStateRef State,
|
|
const char *NL, const char *Sep) const {
|
|
auto ContMap = State->get<ContainerMap>();
|
|
|
|
if (!ContMap.isEmpty()) {
|
|
Out << Sep << "Container Data :" << NL;
|
|
for (const auto &Cont : ContMap) {
|
|
Cont.first->dumpToStream(Out);
|
|
Out << " : [ ";
|
|
const auto CData = Cont.second;
|
|
if (CData.getBegin())
|
|
CData.getBegin()->dumpToStream(Out);
|
|
else
|
|
Out << "<Unknown>";
|
|
Out << " .. ";
|
|
if (CData.getEnd())
|
|
CData.getEnd()->dumpToStream(Out);
|
|
else
|
|
Out << "<Unknown>";
|
|
Out << " ]";
|
|
}
|
|
}
|
|
}
|
|
|
|
namespace {
|
|
|
|
bool isBeginCall(const FunctionDecl *Func) {
|
|
const auto *IdInfo = Func->getIdentifier();
|
|
if (!IdInfo)
|
|
return false;
|
|
return IdInfo->getName().endswith_lower("begin");
|
|
}
|
|
|
|
bool isEndCall(const FunctionDecl *Func) {
|
|
const auto *IdInfo = Func->getIdentifier();
|
|
if (!IdInfo)
|
|
return false;
|
|
return IdInfo->getName().endswith_lower("end");
|
|
}
|
|
|
|
const CXXRecordDecl *getCXXRecordDecl(ProgramStateRef State,
|
|
const MemRegion *Reg) {
|
|
auto TI = getDynamicTypeInfo(State, Reg);
|
|
if (!TI.isValid())
|
|
return nullptr;
|
|
|
|
auto Type = TI.getType();
|
|
if (const auto *RefT = Type->getAs<ReferenceType>()) {
|
|
Type = RefT->getPointeeType();
|
|
}
|
|
|
|
return Type->getUnqualifiedDesugaredType()->getAsCXXRecordDecl();
|
|
}
|
|
|
|
bool hasSubscriptOperator(ProgramStateRef State, const MemRegion *Reg) {
|
|
const auto *CRD = getCXXRecordDecl(State, Reg);
|
|
if (!CRD)
|
|
return false;
|
|
|
|
for (const auto *Method : CRD->methods()) {
|
|
if (!Method->isOverloadedOperator())
|
|
continue;
|
|
const auto OPK = Method->getOverloadedOperator();
|
|
if (OPK == OO_Subscript) {
|
|
return true;
|
|
}
|
|
}
|
|
return false;
|
|
}
|
|
|
|
bool frontModifiable(ProgramStateRef State, const MemRegion *Reg) {
|
|
const auto *CRD = getCXXRecordDecl(State, Reg);
|
|
if (!CRD)
|
|
return false;
|
|
|
|
for (const auto *Method : CRD->methods()) {
|
|
if (!Method->getDeclName().isIdentifier())
|
|
continue;
|
|
if (Method->getName() == "push_front" || Method->getName() == "pop_front") {
|
|
return true;
|
|
}
|
|
}
|
|
return false;
|
|
}
|
|
|
|
bool backModifiable(ProgramStateRef State, const MemRegion *Reg) {
|
|
const auto *CRD = getCXXRecordDecl(State, Reg);
|
|
if (!CRD)
|
|
return false;
|
|
|
|
for (const auto *Method : CRD->methods()) {
|
|
if (!Method->getDeclName().isIdentifier())
|
|
continue;
|
|
if (Method->getName() == "push_back" || Method->getName() == "pop_back") {
|
|
return true;
|
|
}
|
|
}
|
|
return false;
|
|
}
|
|
|
|
SymbolRef getContainerBegin(ProgramStateRef State, const MemRegion *Cont) {
|
|
const auto *CDataPtr = getContainerData(State, Cont);
|
|
if (!CDataPtr)
|
|
return nullptr;
|
|
|
|
return CDataPtr->getBegin();
|
|
}
|
|
|
|
SymbolRef getContainerEnd(ProgramStateRef State, const MemRegion *Cont) {
|
|
const auto *CDataPtr = getContainerData(State, Cont);
|
|
if (!CDataPtr)
|
|
return nullptr;
|
|
|
|
return CDataPtr->getEnd();
|
|
}
|
|
|
|
ProgramStateRef createContainerBegin(ProgramStateRef State,
|
|
const MemRegion *Cont, const Expr *E,
|
|
QualType T, const LocationContext *LCtx,
|
|
unsigned BlockCount) {
|
|
// Only create if it does not exist
|
|
const auto *CDataPtr = getContainerData(State, Cont);
|
|
if (CDataPtr && CDataPtr->getBegin())
|
|
return State;
|
|
|
|
auto &SymMgr = State->getSymbolManager();
|
|
const SymbolConjured *Sym = SymMgr.conjureSymbol(E, LCtx, T, BlockCount,
|
|
"begin");
|
|
State = assumeNoOverflow(State, Sym, 4);
|
|
|
|
if (CDataPtr) {
|
|
const auto CData = CDataPtr->newBegin(Sym);
|
|
return setContainerData(State, Cont, CData);
|
|
}
|
|
|
|
const auto CData = ContainerData::fromBegin(Sym);
|
|
return setContainerData(State, Cont, CData);
|
|
}
|
|
|
|
ProgramStateRef createContainerEnd(ProgramStateRef State, const MemRegion *Cont,
|
|
const Expr *E, QualType T,
|
|
const LocationContext *LCtx,
|
|
unsigned BlockCount) {
|
|
// Only create if it does not exist
|
|
const auto *CDataPtr = getContainerData(State, Cont);
|
|
if (CDataPtr && CDataPtr->getEnd())
|
|
return State;
|
|
|
|
auto &SymMgr = State->getSymbolManager();
|
|
const SymbolConjured *Sym = SymMgr.conjureSymbol(E, LCtx, T, BlockCount,
|
|
"end");
|
|
State = assumeNoOverflow(State, Sym, 4);
|
|
|
|
if (CDataPtr) {
|
|
const auto CData = CDataPtr->newEnd(Sym);
|
|
return setContainerData(State, Cont, CData);
|
|
}
|
|
|
|
const auto CData = ContainerData::fromEnd(Sym);
|
|
return setContainerData(State, Cont, CData);
|
|
}
|
|
|
|
ProgramStateRef setContainerData(ProgramStateRef State, const MemRegion *Cont,
|
|
const ContainerData &CData) {
|
|
return State->set<ContainerMap>(Cont, CData);
|
|
}
|
|
|
|
template <typename Condition, typename Process>
|
|
ProgramStateRef processIteratorPositions(ProgramStateRef State, Condition Cond,
|
|
Process Proc) {
|
|
auto &RegionMapFactory = State->get_context<IteratorRegionMap>();
|
|
auto RegionMap = State->get<IteratorRegionMap>();
|
|
bool Changed = false;
|
|
for (const auto &Reg : RegionMap) {
|
|
if (Cond(Reg.second)) {
|
|
RegionMap = RegionMapFactory.add(RegionMap, Reg.first, Proc(Reg.second));
|
|
Changed = true;
|
|
}
|
|
}
|
|
|
|
if (Changed)
|
|
State = State->set<IteratorRegionMap>(RegionMap);
|
|
|
|
auto &SymbolMapFactory = State->get_context<IteratorSymbolMap>();
|
|
auto SymbolMap = State->get<IteratorSymbolMap>();
|
|
Changed = false;
|
|
for (const auto &Sym : SymbolMap) {
|
|
if (Cond(Sym.second)) {
|
|
SymbolMap = SymbolMapFactory.add(SymbolMap, Sym.first, Proc(Sym.second));
|
|
Changed = true;
|
|
}
|
|
}
|
|
|
|
if (Changed)
|
|
State = State->set<IteratorSymbolMap>(SymbolMap);
|
|
|
|
return State;
|
|
}
|
|
|
|
ProgramStateRef invalidateAllIteratorPositions(ProgramStateRef State,
|
|
const MemRegion *Cont) {
|
|
auto MatchCont = [&](const IteratorPosition &Pos) {
|
|
return Pos.getContainer() == Cont;
|
|
};
|
|
auto Invalidate = [&](const IteratorPosition &Pos) {
|
|
return Pos.invalidate();
|
|
};
|
|
return processIteratorPositions(State, MatchCont, Invalidate);
|
|
}
|
|
|
|
ProgramStateRef
|
|
invalidateAllIteratorPositionsExcept(ProgramStateRef State,
|
|
const MemRegion *Cont, SymbolRef Offset,
|
|
BinaryOperator::Opcode Opc) {
|
|
auto MatchContAndCompare = [&](const IteratorPosition &Pos) {
|
|
return Pos.getContainer() == Cont &&
|
|
!compare(State, Pos.getOffset(), Offset, Opc);
|
|
};
|
|
auto Invalidate = [&](const IteratorPosition &Pos) {
|
|
return Pos.invalidate();
|
|
};
|
|
return processIteratorPositions(State, MatchContAndCompare, Invalidate);
|
|
}
|
|
|
|
ProgramStateRef invalidateIteratorPositions(ProgramStateRef State,
|
|
SymbolRef Offset,
|
|
BinaryOperator::Opcode Opc) {
|
|
auto Compare = [&](const IteratorPosition &Pos) {
|
|
return compare(State, Pos.getOffset(), Offset, Opc);
|
|
};
|
|
auto Invalidate = [&](const IteratorPosition &Pos) {
|
|
return Pos.invalidate();
|
|
};
|
|
return processIteratorPositions(State, Compare, Invalidate);
|
|
}
|
|
|
|
ProgramStateRef invalidateIteratorPositions(ProgramStateRef State,
|
|
SymbolRef Offset1,
|
|
BinaryOperator::Opcode Opc1,
|
|
SymbolRef Offset2,
|
|
BinaryOperator::Opcode Opc2) {
|
|
auto Compare = [&](const IteratorPosition &Pos) {
|
|
return compare(State, Pos.getOffset(), Offset1, Opc1) &&
|
|
compare(State, Pos.getOffset(), Offset2, Opc2);
|
|
};
|
|
auto Invalidate = [&](const IteratorPosition &Pos) {
|
|
return Pos.invalidate();
|
|
};
|
|
return processIteratorPositions(State, Compare, Invalidate);
|
|
}
|
|
|
|
ProgramStateRef reassignAllIteratorPositions(ProgramStateRef State,
|
|
const MemRegion *Cont,
|
|
const MemRegion *NewCont) {
|
|
auto MatchCont = [&](const IteratorPosition &Pos) {
|
|
return Pos.getContainer() == Cont;
|
|
};
|
|
auto ReAssign = [&](const IteratorPosition &Pos) {
|
|
return Pos.reAssign(NewCont);
|
|
};
|
|
return processIteratorPositions(State, MatchCont, ReAssign);
|
|
}
|
|
|
|
ProgramStateRef reassignAllIteratorPositionsUnless(ProgramStateRef State,
|
|
const MemRegion *Cont,
|
|
const MemRegion *NewCont,
|
|
SymbolRef Offset,
|
|
BinaryOperator::Opcode Opc) {
|
|
auto MatchContAndCompare = [&](const IteratorPosition &Pos) {
|
|
return Pos.getContainer() == Cont &&
|
|
!compare(State, Pos.getOffset(), Offset, Opc);
|
|
};
|
|
auto ReAssign = [&](const IteratorPosition &Pos) {
|
|
return Pos.reAssign(NewCont);
|
|
};
|
|
return processIteratorPositions(State, MatchContAndCompare, ReAssign);
|
|
}
|
|
|
|
// This function rebases symbolic expression `OldSym + Int` to `NewSym + Int`,
|
|
// `OldSym - Int` to `NewSym - Int` and `OldSym` to `NewSym` in any iterator
|
|
// position offsets where `CondSym` is true.
|
|
ProgramStateRef rebaseSymbolInIteratorPositionsIf(
|
|
ProgramStateRef State, SValBuilder &SVB, SymbolRef OldSym,
|
|
SymbolRef NewSym, SymbolRef CondSym, BinaryOperator::Opcode Opc) {
|
|
auto LessThanEnd = [&](const IteratorPosition &Pos) {
|
|
return compare(State, Pos.getOffset(), CondSym, Opc);
|
|
};
|
|
auto RebaseSymbol = [&](const IteratorPosition &Pos) {
|
|
return Pos.setTo(rebaseSymbol(State, SVB, Pos.getOffset(), OldSym,
|
|
NewSym));
|
|
};
|
|
return processIteratorPositions(State, LessThanEnd, RebaseSymbol);
|
|
}
|
|
|
|
// This function rebases symbolic expression `OldExpr + Int` to `NewExpr + Int`,
|
|
// `OldExpr - Int` to `NewExpr - Int` and `OldExpr` to `NewExpr` in expression
|
|
// `OrigExpr`.
|
|
SymbolRef rebaseSymbol(ProgramStateRef State, SValBuilder &SVB,
|
|
SymbolRef OrigExpr, SymbolRef OldExpr,
|
|
SymbolRef NewSym) {
|
|
auto &SymMgr = SVB.getSymbolManager();
|
|
auto Diff = SVB.evalBinOpNN(State, BO_Sub, nonloc::SymbolVal(OrigExpr),
|
|
nonloc::SymbolVal(OldExpr),
|
|
SymMgr.getType(OrigExpr));
|
|
|
|
const auto DiffInt = Diff.getAs<nonloc::ConcreteInt>();
|
|
if (!DiffInt)
|
|
return OrigExpr;
|
|
|
|
return SVB.evalBinOpNN(State, BO_Add, *DiffInt, nonloc::SymbolVal(NewSym),
|
|
SymMgr.getType(OrigExpr)).getAsSymbol();
|
|
}
|
|
|
|
bool hasLiveIterators(ProgramStateRef State, const MemRegion *Cont) {
|
|
auto RegionMap = State->get<IteratorRegionMap>();
|
|
for (const auto &Reg : RegionMap) {
|
|
if (Reg.second.getContainer() == Cont)
|
|
return true;
|
|
}
|
|
|
|
auto SymbolMap = State->get<IteratorSymbolMap>();
|
|
for (const auto &Sym : SymbolMap) {
|
|
if (Sym.second.getContainer() == Cont)
|
|
return true;
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
} // namespace
|
|
|
|
void ento::registerContainerModeling(CheckerManager &mgr) {
|
|
mgr.registerChecker<ContainerModeling>();
|
|
}
|
|
|
|
bool ento::shouldRegisterContainerModeling(const CheckerManager &mgr) {
|
|
if (!mgr.getLangOpts().CPlusPlus)
|
|
return false;
|
|
|
|
if (!mgr.getAnalyzerOptions().ShouldAggressivelySimplifyBinaryOperation) {
|
|
mgr.getASTContext().getDiagnostics().Report(
|
|
diag::err_analyzer_checker_incompatible_analyzer_option)
|
|
<< "aggressive-binary-operation-simplification" << "false";
|
|
return false;
|
|
}
|
|
|
|
return true;
|
|
}
|