| //===- BugReporter.cpp - Generate PathDiagnostics for bugs ----------------===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file defines BugReporter, a utility class for generating |
| // PathDiagnostics. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "clang/StaticAnalyzer/Core/BugReporter/BugReporter.h" |
| #include "clang/AST/Decl.h" |
| #include "clang/AST/DeclBase.h" |
| #include "clang/AST/DeclObjC.h" |
| #include "clang/AST/Expr.h" |
| #include "clang/AST/ExprCXX.h" |
| #include "clang/AST/ParentMap.h" |
| #include "clang/AST/Stmt.h" |
| #include "clang/AST/StmtCXX.h" |
| #include "clang/AST/StmtObjC.h" |
| #include "clang/Analysis/AnalysisDeclContext.h" |
| #include "clang/Analysis/CFG.h" |
| #include "clang/Analysis/CFGStmtMap.h" |
| #include "clang/Analysis/ProgramPoint.h" |
| #include "clang/Basic/LLVM.h" |
| #include "clang/Basic/SourceLocation.h" |
| #include "clang/Basic/SourceManager.h" |
| #include "clang/StaticAnalyzer/Core/AnalyzerOptions.h" |
| #include "clang/StaticAnalyzer/Core/BugReporter/BugReporterVisitors.h" |
| #include "clang/StaticAnalyzer/Core/BugReporter/BugType.h" |
| #include "clang/StaticAnalyzer/Core/BugReporter/PathDiagnostic.h" |
| #include "clang/StaticAnalyzer/Core/Checker.h" |
| #include "clang/StaticAnalyzer/Core/CheckerManager.h" |
| #include "clang/StaticAnalyzer/Core/PathSensitive/ExplodedGraph.h" |
| #include "clang/StaticAnalyzer/Core/PathSensitive/ExprEngine.h" |
| #include "clang/StaticAnalyzer/Core/PathSensitive/MemRegion.h" |
| #include "clang/StaticAnalyzer/Core/PathSensitive/ProgramState.h" |
| #include "clang/StaticAnalyzer/Core/PathSensitive/SVals.h" |
| #include "clang/StaticAnalyzer/Core/PathSensitive/SymbolManager.h" |
| #include "llvm/ADT/ArrayRef.h" |
| #include "llvm/ADT/DenseMap.h" |
| #include "llvm/ADT/DenseSet.h" |
| #include "llvm/ADT/FoldingSet.h" |
| #include "llvm/ADT/None.h" |
| #include "llvm/ADT/Optional.h" |
| #include "llvm/ADT/STLExtras.h" |
| #include "llvm/ADT/SmallPtrSet.h" |
| #include "llvm/ADT/SmallString.h" |
| #include "llvm/ADT/SmallVector.h" |
| #include "llvm/ADT/Statistic.h" |
| #include "llvm/ADT/StringRef.h" |
| #include "llvm/ADT/iterator_range.h" |
| #include "llvm/Support/Casting.h" |
| #include "llvm/Support/Compiler.h" |
| #include "llvm/Support/ErrorHandling.h" |
| #include "llvm/Support/MemoryBuffer.h" |
| #include "llvm/Support/raw_ostream.h" |
| #include <algorithm> |
| #include <cassert> |
| #include <cstddef> |
| #include <iterator> |
| #include <memory> |
| #include <queue> |
| #include <string> |
| #include <tuple> |
| #include <utility> |
| #include <vector> |
| |
| using namespace clang; |
| using namespace ento; |
| |
| #define DEBUG_TYPE "BugReporter" |
| |
| STATISTIC(MaxBugClassSize, |
| "The maximum number of bug reports in the same equivalence class"); |
| STATISTIC(MaxValidBugClassSize, |
| "The maximum number of bug reports in the same equivalence class " |
| "where at least one report is valid (not suppressed)"); |
| |
| BugReporterVisitor::~BugReporterVisitor() = default; |
| |
| void BugReporterContext::anchor() {} |
| |
| //===----------------------------------------------------------------------===// |
| // Helper routines for walking the ExplodedGraph and fetching statements. |
| //===----------------------------------------------------------------------===// |
| |
| static const Stmt *GetPreviousStmt(const ExplodedNode *N) { |
| for (N = N->getFirstPred(); N; N = N->getFirstPred()) |
| if (const Stmt *S = PathDiagnosticLocation::getStmt(N)) |
| return S; |
| |
| return nullptr; |
| } |
| |
| static inline const Stmt* |
| GetCurrentOrPreviousStmt(const ExplodedNode *N) { |
| if (const Stmt *S = PathDiagnosticLocation::getStmt(N)) |
| return S; |
| |
| return GetPreviousStmt(N); |
| } |
| |
| //===----------------------------------------------------------------------===// |
| // Diagnostic cleanup. |
| //===----------------------------------------------------------------------===// |
| |
| static PathDiagnosticEventPiece * |
| eventsDescribeSameCondition(PathDiagnosticEventPiece *X, |
| PathDiagnosticEventPiece *Y) { |
| // Prefer diagnostics that come from ConditionBRVisitor over |
| // those that came from TrackConstraintBRVisitor, |
| // unless the one from ConditionBRVisitor is |
| // its generic fallback diagnostic. |
| const void *tagPreferred = ConditionBRVisitor::getTag(); |
| const void *tagLesser = TrackConstraintBRVisitor::getTag(); |
| |
| if (X->getLocation() != Y->getLocation()) |
| return nullptr; |
| |
| if (X->getTag() == tagPreferred && Y->getTag() == tagLesser) |
| return ConditionBRVisitor::isPieceMessageGeneric(X) ? Y : X; |
| |
| if (Y->getTag() == tagPreferred && X->getTag() == tagLesser) |
| return ConditionBRVisitor::isPieceMessageGeneric(Y) ? X : Y; |
| |
| return nullptr; |
| } |
| |
| /// An optimization pass over PathPieces that removes redundant diagnostics |
| /// generated by both ConditionBRVisitor and TrackConstraintBRVisitor. Both |
| /// BugReporterVisitors use different methods to generate diagnostics, with |
| /// one capable of emitting diagnostics in some cases but not in others. This |
| /// can lead to redundant diagnostic pieces at the same point in a path. |
| static void removeRedundantMsgs(PathPieces &path) { |
| unsigned N = path.size(); |
| if (N < 2) |
| return; |
| // NOTE: this loop intentionally is not using an iterator. Instead, we |
| // are streaming the path and modifying it in place. This is done by |
| // grabbing the front, processing it, and if we decide to keep it append |
| // it to the end of the path. The entire path is processed in this way. |
| for (unsigned i = 0; i < N; ++i) { |
| auto piece = std::move(path.front()); |
| path.pop_front(); |
| |
| switch (piece->getKind()) { |
| case PathDiagnosticPiece::Call: |
| removeRedundantMsgs(cast<PathDiagnosticCallPiece>(*piece).path); |
| break; |
| case PathDiagnosticPiece::Macro: |
| removeRedundantMsgs(cast<PathDiagnosticMacroPiece>(*piece).subPieces); |
| break; |
| case PathDiagnosticPiece::ControlFlow: |
| break; |
| case PathDiagnosticPiece::Event: { |
| if (i == N-1) |
| break; |
| |
| if (auto *nextEvent = |
| dyn_cast<PathDiagnosticEventPiece>(path.front().get())) { |
| auto *event = cast<PathDiagnosticEventPiece>(piece.get()); |
| // Check to see if we should keep one of the two pieces. If we |
| // come up with a preference, record which piece to keep, and consume |
| // another piece from the path. |
| if (auto *pieceToKeep = |
| eventsDescribeSameCondition(event, nextEvent)) { |
| piece = std::move(pieceToKeep == event ? piece : path.front()); |
| path.pop_front(); |
| ++i; |
| } |
| } |
| break; |
| } |
| case PathDiagnosticPiece::Note: |
| break; |
| } |
| path.push_back(std::move(piece)); |
| } |
| } |
| |
| /// A map from PathDiagnosticPiece to the LocationContext of the inlined |
| /// function call it represents. |
| using LocationContextMap = |
| llvm::DenseMap<const PathPieces *, const LocationContext *>; |
| |
| /// Recursively scan through a path and prune out calls and macros pieces |
| /// that aren't needed. Return true if afterwards the path contains |
| /// "interesting stuff" which means it shouldn't be pruned from the parent path. |
| static bool removeUnneededCalls(PathPieces &pieces, BugReport *R, |
| LocationContextMap &LCM, |
| bool IsInteresting = false) { |
| bool containsSomethingInteresting = IsInteresting; |
| const unsigned N = pieces.size(); |
| |
| for (unsigned i = 0 ; i < N ; ++i) { |
| // Remove the front piece from the path. If it is still something we |
| // want to keep once we are done, we will push it back on the end. |
| auto piece = std::move(pieces.front()); |
| pieces.pop_front(); |
| |
| switch (piece->getKind()) { |
| case PathDiagnosticPiece::Call: { |
| auto &call = cast<PathDiagnosticCallPiece>(*piece); |
| // Check if the location context is interesting. |
| assert(LCM.count(&call.path)); |
| if (!removeUnneededCalls(call.path, R, LCM, |
| R->isInteresting(LCM[&call.path]))) |
| continue; |
| |
| containsSomethingInteresting = true; |
| break; |
| } |
| case PathDiagnosticPiece::Macro: { |
| auto ¯o = cast<PathDiagnosticMacroPiece>(*piece); |
| if (!removeUnneededCalls(macro.subPieces, R, LCM, IsInteresting)) |
| continue; |
| containsSomethingInteresting = true; |
| break; |
| } |
| case PathDiagnosticPiece::Event: { |
| auto &event = cast<PathDiagnosticEventPiece>(*piece); |
| |
| // We never throw away an event, but we do throw it away wholesale |
| // as part of a path if we throw the entire path away. |
| containsSomethingInteresting |= !event.isPrunable(); |
| break; |
| } |
| case PathDiagnosticPiece::ControlFlow: |
| break; |
| |
| case PathDiagnosticPiece::Note: |
| break; |
| } |
| |
| pieces.push_back(std::move(piece)); |
| } |
| |
| return containsSomethingInteresting; |
| } |
| |
| /// Returns true if the given decl has been implicitly given a body, either by |
| /// the analyzer or by the compiler proper. |
| static bool hasImplicitBody(const Decl *D) { |
| assert(D); |
| return D->isImplicit() || !D->hasBody(); |
| } |
| |
| /// Recursively scan through a path and make sure that all call pieces have |
| /// valid locations. |
| static void |
| adjustCallLocations(PathPieces &Pieces, |
| PathDiagnosticLocation *LastCallLocation = nullptr) { |
| for (const auto &I : Pieces) { |
| auto *Call = dyn_cast<PathDiagnosticCallPiece>(I.get()); |
| |
| if (!Call) |
| continue; |
| |
| if (LastCallLocation) { |
| bool CallerIsImplicit = hasImplicitBody(Call->getCaller()); |
| if (CallerIsImplicit || !Call->callEnter.asLocation().isValid()) |
| Call->callEnter = *LastCallLocation; |
| if (CallerIsImplicit || !Call->callReturn.asLocation().isValid()) |
| Call->callReturn = *LastCallLocation; |
| } |
| |
| // Recursively clean out the subclass. Keep this call around if |
| // it contains any informative diagnostics. |
| PathDiagnosticLocation *ThisCallLocation; |
| if (Call->callEnterWithin.asLocation().isValid() && |
| !hasImplicitBody(Call->getCallee())) |
| ThisCallLocation = &Call->callEnterWithin; |
| else |
| ThisCallLocation = &Call->callEnter; |
| |
| assert(ThisCallLocation && "Outermost call has an invalid location"); |
| adjustCallLocations(Call->path, ThisCallLocation); |
| } |
| } |
| |
| /// Remove edges in and out of C++ default initializer expressions. These are |
| /// for fields that have in-class initializers, as opposed to being initialized |
| /// explicitly in a constructor or braced list. |
| static void removeEdgesToDefaultInitializers(PathPieces &Pieces) { |
| for (PathPieces::iterator I = Pieces.begin(), E = Pieces.end(); I != E;) { |
| if (auto *C = dyn_cast<PathDiagnosticCallPiece>(I->get())) |
| removeEdgesToDefaultInitializers(C->path); |
| |
| if (auto *M = dyn_cast<PathDiagnosticMacroPiece>(I->get())) |
| removeEdgesToDefaultInitializers(M->subPieces); |
| |
| if (auto *CF = dyn_cast<PathDiagnosticControlFlowPiece>(I->get())) { |
| const Stmt *Start = CF->getStartLocation().asStmt(); |
| const Stmt *End = CF->getEndLocation().asStmt(); |
| if (Start && isa<CXXDefaultInitExpr>(Start)) { |
| I = Pieces.erase(I); |
| continue; |
| } else if (End && isa<CXXDefaultInitExpr>(End)) { |
| PathPieces::iterator Next = std::next(I); |
| if (Next != E) { |
| if (auto *NextCF = |
| dyn_cast<PathDiagnosticControlFlowPiece>(Next->get())) { |
| NextCF->setStartLocation(CF->getStartLocation()); |
| } |
| } |
| I = Pieces.erase(I); |
| continue; |
| } |
| } |
| |
| I++; |
| } |
| } |
| |
| /// Remove all pieces with invalid locations as these cannot be serialized. |
| /// We might have pieces with invalid locations as a result of inlining Body |
| /// Farm generated functions. |
| static void removePiecesWithInvalidLocations(PathPieces &Pieces) { |
| for (PathPieces::iterator I = Pieces.begin(), E = Pieces.end(); I != E;) { |
| if (auto *C = dyn_cast<PathDiagnosticCallPiece>(I->get())) |
| removePiecesWithInvalidLocations(C->path); |
| |
| if (auto *M = dyn_cast<PathDiagnosticMacroPiece>(I->get())) |
| removePiecesWithInvalidLocations(M->subPieces); |
| |
| if (!(*I)->getLocation().isValid() || |
| !(*I)->getLocation().asLocation().isValid()) { |
| I = Pieces.erase(I); |
| continue; |
| } |
| I++; |
| } |
| } |
| |
| //===----------------------------------------------------------------------===// |
| // PathDiagnosticBuilder and its associated routines and helper objects. |
| //===----------------------------------------------------------------------===// |
| |
| namespace { |
| |
| class PathDiagnosticBuilder : public BugReporterContext { |
| BugReport *R; |
| PathDiagnosticConsumer *PDC; |
| |
| public: |
| const LocationContext *LC; |
| |
| PathDiagnosticBuilder(GRBugReporter &br, |
| BugReport *r, InterExplodedGraphMap &Backmap, |
| PathDiagnosticConsumer *pdc) |
| : BugReporterContext(br, Backmap), R(r), PDC(pdc), |
| LC(r->getErrorNode()->getLocationContext()) {} |
| |
| PathDiagnosticLocation ExecutionContinues(const ExplodedNode *N); |
| |
| PathDiagnosticLocation ExecutionContinues(llvm::raw_string_ostream &os, |
| const ExplodedNode *N); |
| |
| BugReport *getBugReport() { return R; } |
| |
| Decl const &getCodeDecl() { return R->getErrorNode()->getCodeDecl(); } |
| |
| ParentMap& getParentMap() { return LC->getParentMap(); } |
| |
| const Stmt *getParent(const Stmt *S) { |
| return getParentMap().getParent(S); |
| } |
| |
| PathDiagnosticLocation getEnclosingStmtLocation(const Stmt *S); |
| |
| PathDiagnosticConsumer::PathGenerationScheme getGenerationScheme() const { |
| return PDC ? PDC->getGenerationScheme() : PathDiagnosticConsumer::Minimal; |
| } |
| |
| bool supportsLogicalOpControlFlow() const { |
| return PDC ? PDC->supportsLogicalOpControlFlow() : true; |
| } |
| }; |
| |
| } // namespace |
| |
| PathDiagnosticLocation |
| PathDiagnosticBuilder::ExecutionContinues(const ExplodedNode *N) { |
| if (const Stmt *S = PathDiagnosticLocation::getNextStmt(N)) |
| return PathDiagnosticLocation(S, getSourceManager(), LC); |
| |
| return PathDiagnosticLocation::createDeclEnd(N->getLocationContext(), |
| getSourceManager()); |
| } |
| |
| PathDiagnosticLocation |
| PathDiagnosticBuilder::ExecutionContinues(llvm::raw_string_ostream &os, |
| const ExplodedNode *N) { |
| // Slow, but probably doesn't matter. |
| if (os.str().empty()) |
| os << ' '; |
| |
| const PathDiagnosticLocation &Loc = ExecutionContinues(N); |
| |
| if (Loc.asStmt()) |
| os << "Execution continues on line " |
| << getSourceManager().getExpansionLineNumber(Loc.asLocation()) |
| << '.'; |
| else { |
| os << "Execution jumps to the end of the "; |
| const Decl *D = N->getLocationContext()->getDecl(); |
| if (isa<ObjCMethodDecl>(D)) |
| os << "method"; |
| else if (isa<FunctionDecl>(D)) |
| os << "function"; |
| else { |
| assert(isa<BlockDecl>(D)); |
| os << "anonymous block"; |
| } |
| os << '.'; |
| } |
| |
| return Loc; |
| } |
| |
| static const Stmt *getEnclosingParent(const Stmt *S, const ParentMap &PM) { |
| if (isa<Expr>(S) && PM.isConsumedExpr(cast<Expr>(S))) |
| return PM.getParentIgnoreParens(S); |
| |
| const Stmt *Parent = PM.getParentIgnoreParens(S); |
| if (!Parent) |
| return nullptr; |
| |
| switch (Parent->getStmtClass()) { |
| case Stmt::ForStmtClass: |
| case Stmt::DoStmtClass: |
| case Stmt::WhileStmtClass: |
| case Stmt::ObjCForCollectionStmtClass: |
| case Stmt::CXXForRangeStmtClass: |
| return Parent; |
| default: |
| break; |
| } |
| |
| return nullptr; |
| } |
| |
| static PathDiagnosticLocation |
| getEnclosingStmtLocation(const Stmt *S, SourceManager &SMgr, const ParentMap &P, |
| const LocationContext *LC, bool allowNestedContexts) { |
| if (!S) |
| return {}; |
| |
| while (const Stmt *Parent = getEnclosingParent(S, P)) { |
| switch (Parent->getStmtClass()) { |
| case Stmt::BinaryOperatorClass: { |
| const auto *B = cast<BinaryOperator>(Parent); |
| if (B->isLogicalOp()) |
| return PathDiagnosticLocation(allowNestedContexts ? B : S, SMgr, LC); |
| break; |
| } |
| case Stmt::CompoundStmtClass: |
| case Stmt::StmtExprClass: |
| return PathDiagnosticLocation(S, SMgr, LC); |
| case Stmt::ChooseExprClass: |
| // Similar to '?' if we are referring to condition, just have the edge |
| // point to the entire choose expression. |
| if (allowNestedContexts || cast<ChooseExpr>(Parent)->getCond() == S) |
| return PathDiagnosticLocation(Parent, SMgr, LC); |
| else |
| return PathDiagnosticLocation(S, SMgr, LC); |
| case Stmt::BinaryConditionalOperatorClass: |
| case Stmt::ConditionalOperatorClass: |
| // For '?', if we are referring to condition, just have the edge point |
| // to the entire '?' expression. |
| if (allowNestedContexts || |
| cast<AbstractConditionalOperator>(Parent)->getCond() == S) |
| return PathDiagnosticLocation(Parent, SMgr, LC); |
| else |
| return PathDiagnosticLocation(S, SMgr, LC); |
| case Stmt::CXXForRangeStmtClass: |
| if (cast<CXXForRangeStmt>(Parent)->getBody() == S) |
| return PathDiagnosticLocation(S, SMgr, LC); |
| break; |
| case Stmt::DoStmtClass: |
| return PathDiagnosticLocation(S, SMgr, LC); |
| case Stmt::ForStmtClass: |
| if (cast<ForStmt>(Parent)->getBody() == S) |
| return PathDiagnosticLocation(S, SMgr, LC); |
| break; |
| case Stmt::IfStmtClass: |
| if (cast<IfStmt>(Parent)->getCond() != S) |
| return PathDiagnosticLocation(S, SMgr, LC); |
| break; |
| case Stmt::ObjCForCollectionStmtClass: |
| if (cast<ObjCForCollectionStmt>(Parent)->getBody() == S) |
| return PathDiagnosticLocation(S, SMgr, LC); |
| break; |
| case Stmt::WhileStmtClass: |
| if (cast<WhileStmt>(Parent)->getCond() != S) |
| return PathDiagnosticLocation(S, SMgr, LC); |
| break; |
| default: |
| break; |
| } |
| |
| S = Parent; |
| } |
| |
| assert(S && "Cannot have null Stmt for PathDiagnosticLocation"); |
| |
| return PathDiagnosticLocation(S, SMgr, LC); |
| } |
| |
| PathDiagnosticLocation |
| PathDiagnosticBuilder::getEnclosingStmtLocation(const Stmt *S) { |
| assert(S && "Null Stmt passed to getEnclosingStmtLocation"); |
| return ::getEnclosingStmtLocation(S, getSourceManager(), getParentMap(), LC, |
| /*allowNestedContexts=*/false); |
| } |
| |
| //===----------------------------------------------------------------------===// |
| // "Minimal" path diagnostic generation algorithm. |
| //===----------------------------------------------------------------------===// |
| using StackDiagPair = |
| std::pair<PathDiagnosticCallPiece *, const ExplodedNode *>; |
| using StackDiagVector = SmallVector<StackDiagPair, 6>; |
| |
| static void updateStackPiecesWithMessage(PathDiagnosticPiece &P, |
| StackDiagVector &CallStack) { |
| // If the piece contains a special message, add it to all the call |
| // pieces on the active stack. |
| if (auto *ep = dyn_cast<PathDiagnosticEventPiece>(&P)) { |
| if (ep->hasCallStackHint()) |
| for (const auto &I : CallStack) { |
| PathDiagnosticCallPiece *CP = I.first; |
| const ExplodedNode *N = I.second; |
| std::string stackMsg = ep->getCallStackMessage(N); |
| |
| // The last message on the path to final bug is the most important |
| // one. Since we traverse the path backwards, do not add the message |
| // if one has been previously added. |
| if (!CP->hasCallStackMessage()) |
| CP->setCallStackMessage(stackMsg); |
| } |
| } |
| } |
| |
| static void CompactPathDiagnostic(PathPieces &path, const SourceManager& SM); |
| |
| |
| std::shared_ptr<PathDiagnosticControlFlowPiece> generateDiagForSwitchOP( |
| const ExplodedNode *N, |
| const CFGBlock *Dst, |
| const SourceManager &SM, |
| const LocationContext *LC, |
| PathDiagnosticBuilder &PDB, |
| PathDiagnosticLocation &Start |
| ) { |
| // Figure out what case arm we took. |
| std::string sbuf; |
| llvm::raw_string_ostream os(sbuf); |
| PathDiagnosticLocation End; |
| |
| if (const Stmt *S = Dst->getLabel()) { |
| End = PathDiagnosticLocation(S, SM, LC); |
| |
| switch (S->getStmtClass()) { |
| default: |
| os << "No cases match in the switch statement. " |
| "Control jumps to line " |
| << End.asLocation().getExpansionLineNumber(); |
| break; |
| case Stmt::DefaultStmtClass: |
| os << "Control jumps to the 'default' case at line " |
| << End.asLocation().getExpansionLineNumber(); |
| break; |
| |
| case Stmt::CaseStmtClass: { |
| os << "Control jumps to 'case "; |
| const auto *Case = cast<CaseStmt>(S); |
| const Expr *LHS = Case->getLHS()->IgnoreParenCasts(); |
| |
| // Determine if it is an enum. |
| bool GetRawInt = true; |
| |
| if (const auto *DR = dyn_cast<DeclRefExpr>(LHS)) { |
| // FIXME: Maybe this should be an assertion. Are there cases |
| // were it is not an EnumConstantDecl? |
| const auto *D = dyn_cast<EnumConstantDecl>(DR->getDecl()); |
| |
| if (D) { |
| GetRawInt = false; |
| os << *D; |
| } |
| } |
| |
| if (GetRawInt) |
| os << LHS->EvaluateKnownConstInt(PDB.getASTContext()); |
| |
| os << ":' at line " << End.asLocation().getExpansionLineNumber(); |
| break; |
| } |
| } |
| } else { |
| os << "'Default' branch taken. "; |
| End = PDB.ExecutionContinues(os, N); |
| } |
| return std::make_shared<PathDiagnosticControlFlowPiece>(Start, End, |
| os.str()); |
| } |
| |
| |
| std::shared_ptr<PathDiagnosticControlFlowPiece> generateDiagForGotoOP( |
| const Stmt *S, |
| PathDiagnosticBuilder &PDB, |
| PathDiagnosticLocation &Start) { |
| std::string sbuf; |
| llvm::raw_string_ostream os(sbuf); |
| const PathDiagnosticLocation &End = PDB.getEnclosingStmtLocation(S); |
| os << "Control jumps to line " << End.asLocation().getExpansionLineNumber(); |
| return std::make_shared<PathDiagnosticControlFlowPiece>(Start, End, os.str()); |
| |
| } |
| |
| std::shared_ptr<PathDiagnosticControlFlowPiece> generateDiagForBinaryOP( |
| const ExplodedNode *N, |
| const Stmt *T, |
| const CFGBlock *Src, |
| const CFGBlock *Dst, |
| const SourceManager &SM, |
| PathDiagnosticBuilder &PDB, |
| const LocationContext *LC) { |
| const auto *B = cast<BinaryOperator>(T); |
| std::string sbuf; |
| llvm::raw_string_ostream os(sbuf); |
| os << "Left side of '"; |
| PathDiagnosticLocation Start, End; |
| |
| if (B->getOpcode() == BO_LAnd) { |
| os << "&&" |
| << "' is "; |
| |
| if (*(Src->succ_begin() + 1) == Dst) { |
| os << "false"; |
| End = PathDiagnosticLocation(B->getLHS(), SM, LC); |
| Start = |
| PathDiagnosticLocation::createOperatorLoc(B, SM); |
| } else { |
| os << "true"; |
| Start = PathDiagnosticLocation(B->getLHS(), SM, LC); |
| End = PDB.ExecutionContinues(N); |
| } |
| } else { |
| assert(B->getOpcode() == BO_LOr); |
| os << "||" |
| << "' is "; |
| |
| if (*(Src->succ_begin() + 1) == Dst) { |
| os << "false"; |
| Start = PathDiagnosticLocation(B->getLHS(), SM, LC); |
| End = PDB.ExecutionContinues(N); |
| } else { |
| os << "true"; |
| End = PathDiagnosticLocation(B->getLHS(), SM, LC); |
| Start = |
| PathDiagnosticLocation::createOperatorLoc(B, SM); |
| } |
| } |
| return std::make_shared<PathDiagnosticControlFlowPiece>(Start, End, |
| os.str()); |
| } |
| |
| void generateMinimalDiagForBlockEdge(const ExplodedNode *N, BlockEdge BE, |
| const SourceManager &SM, |
| PathDiagnosticBuilder &PDB, |
| PathDiagnostic &PD) { |
| const LocationContext *LC = N->getLocationContext(); |
| const CFGBlock *Src = BE.getSrc(); |
| const CFGBlock *Dst = BE.getDst(); |
| const Stmt *T = Src->getTerminator(); |
| if (!T) |
| return; |
| |
| auto Start = PathDiagnosticLocation::createBegin(T, SM, LC); |
| switch (T->getStmtClass()) { |
| default: |
| break; |
| |
| case Stmt::GotoStmtClass: |
| case Stmt::IndirectGotoStmtClass: { |
| if (const Stmt *S = PathDiagnosticLocation::getNextStmt(N)) |
| PD.getActivePath().push_front(generateDiagForGotoOP(S, PDB, Start)); |
| break; |
| } |
| |
| case Stmt::SwitchStmtClass: { |
| PD.getActivePath().push_front( |
| generateDiagForSwitchOP(N, Dst, SM, LC, PDB, Start)); |
| break; |
| } |
| |
| case Stmt::BreakStmtClass: |
| case Stmt::ContinueStmtClass: { |
| std::string sbuf; |
| llvm::raw_string_ostream os(sbuf); |
| PathDiagnosticLocation End = PDB.ExecutionContinues(os, N); |
| PD.getActivePath().push_front( |
| std::make_shared<PathDiagnosticControlFlowPiece>(Start, End, os.str())); |
| break; |
| } |
| |
| // Determine control-flow for ternary '?'. |
| case Stmt::BinaryConditionalOperatorClass: |
| case Stmt::ConditionalOperatorClass: { |
| std::string sbuf; |
| llvm::raw_string_ostream os(sbuf); |
| os << "'?' condition is "; |
| |
| if (*(Src->succ_begin() + 1) == Dst) |
| os << "false"; |
| else |
| os << "true"; |
| |
| PathDiagnosticLocation End = PDB.ExecutionContinues(N); |
| |
| if (const Stmt *S = End.asStmt()) |
| End = PDB.getEnclosingStmtLocation(S); |
| |
| PD.getActivePath().push_front( |
| std::make_shared<PathDiagnosticControlFlowPiece>(Start, End, os.str())); |
| break; |
| } |
| |
| // Determine control-flow for short-circuited '&&' and '||'. |
| case Stmt::BinaryOperatorClass: { |
| if (!PDB.supportsLogicalOpControlFlow()) |
| break; |
| |
| std::shared_ptr<PathDiagnosticControlFlowPiece> Diag = |
| generateDiagForBinaryOP(N, T, Src, Dst, SM, PDB, LC); |
| PD.getActivePath().push_front(Diag); |
| break; |
| } |
| |
| case Stmt::DoStmtClass: |
| if (*(Src->succ_begin()) == Dst) { |
| std::string sbuf; |
| llvm::raw_string_ostream os(sbuf); |
| |
| os << "Loop condition is true. "; |
| PathDiagnosticLocation End = PDB.ExecutionContinues(os, N); |
| |
| if (const Stmt *S = End.asStmt()) |
| End = PDB.getEnclosingStmtLocation(S); |
| |
| PD.getActivePath().push_front( |
| std::make_shared<PathDiagnosticControlFlowPiece>(Start, End, |
| os.str())); |
| } else { |
| PathDiagnosticLocation End = PDB.ExecutionContinues(N); |
| |
| if (const Stmt *S = End.asStmt()) |
| End = PDB.getEnclosingStmtLocation(S); |
| |
| PD.getActivePath().push_front( |
| std::make_shared<PathDiagnosticControlFlowPiece>( |
| Start, End, "Loop condition is false. Exiting loop")); |
| } |
| break; |
| |
| case Stmt::WhileStmtClass: |
| case Stmt::ForStmtClass: |
| if (*(Src->succ_begin() + 1) == Dst) { |
| std::string sbuf; |
| llvm::raw_string_ostream os(sbuf); |
| |
| os << "Loop condition is false. "; |
| PathDiagnosticLocation End = PDB.ExecutionContinues(os, N); |
| if (const Stmt *S = End.asStmt()) |
| End = PDB.getEnclosingStmtLocation(S); |
| |
| PD.getActivePath().push_front( |
| std::make_shared<PathDiagnosticControlFlowPiece>(Start, End, |
| os.str())); |
| } else { |
| PathDiagnosticLocation End = PDB.ExecutionContinues(N); |
| if (const Stmt *S = End.asStmt()) |
| End = PDB.getEnclosingStmtLocation(S); |
| |
| PD.getActivePath().push_front( |
| std::make_shared<PathDiagnosticControlFlowPiece>( |
| Start, End, "Loop condition is true. Entering loop body")); |
| } |
| |
| break; |
| |
| case Stmt::IfStmtClass: { |
| PathDiagnosticLocation End = PDB.ExecutionContinues(N); |
| |
| if (const Stmt *S = End.asStmt()) |
| End = PDB.getEnclosingStmtLocation(S); |
| |
| if (*(Src->succ_begin() + 1) == Dst) |
| PD.getActivePath().push_front( |
| std::make_shared<PathDiagnosticControlFlowPiece>( |
| Start, End, "Taking false branch")); |
| else |
| PD.getActivePath().push_front( |
| std::make_shared<PathDiagnosticControlFlowPiece>( |
| Start, End, "Taking true branch")); |
| |
| break; |
| } |
| } |
| } |
| |
| // Cone-of-influence: support the reverse propagation of "interesting" symbols |
| // and values by tracing interesting calculations backwards through evaluated |
| // expressions along a path. This is probably overly complicated, but the idea |
| // is that if an expression computed an "interesting" value, the child |
| // expressions are are also likely to be "interesting" as well (which then |
| // propagates to the values they in turn compute). This reverse propagation |
| // is needed to track interesting correlations across function call boundaries, |
| // where formal arguments bind to actual arguments, etc. This is also needed |
| // because the constraint solver sometimes simplifies certain symbolic values |
| // into constants when appropriate, and this complicates reasoning about |
| // interesting values. |
| using InterestingExprs = llvm::DenseSet<const Expr *>; |
| |
| static void reversePropagateIntererstingSymbols(BugReport &R, |
| InterestingExprs &IE, |
| const ProgramState *State, |
| const Expr *Ex, |
| const LocationContext *LCtx) { |
| SVal V = State->getSVal(Ex, LCtx); |
| if (!(R.isInteresting(V) || IE.count(Ex))) |
| return; |
| |
| switch (Ex->getStmtClass()) { |
| default: |
| if (!isa<CastExpr>(Ex)) |
| break; |
| // Fall through. |
| case Stmt::BinaryOperatorClass: |
| case Stmt::UnaryOperatorClass: { |
| for (const Stmt *SubStmt : Ex->children()) { |
| if (const auto *child = dyn_cast_or_null<Expr>(SubStmt)) { |
| IE.insert(child); |
| SVal ChildV = State->getSVal(child, LCtx); |
| R.markInteresting(ChildV); |
| } |
| } |
| break; |
| } |
| } |
| |
| R.markInteresting(V); |
| } |
| |
| static void reversePropagateInterestingSymbols(BugReport &R, |
| InterestingExprs &IE, |
| const ProgramState *State, |
| const LocationContext *CalleeCtx, |
| const LocationContext *CallerCtx) |
| { |
| // FIXME: Handle non-CallExpr-based CallEvents. |
| const StackFrameContext *Callee = CalleeCtx->getStackFrame(); |
| const Stmt *CallSite = Callee->getCallSite(); |
| if (const auto *CE = dyn_cast_or_null<CallExpr>(CallSite)) { |
| if (const auto *FD = dyn_cast<FunctionDecl>(CalleeCtx->getDecl())) { |
| FunctionDecl::param_const_iterator PI = FD->param_begin(), |
| PE = FD->param_end(); |
| CallExpr::const_arg_iterator AI = CE->arg_begin(), AE = CE->arg_end(); |
| for (; AI != AE && PI != PE; ++AI, ++PI) { |
| if (const Expr *ArgE = *AI) { |
| if (const ParmVarDecl *PD = *PI) { |
| Loc LV = State->getLValue(PD, CalleeCtx); |
| if (R.isInteresting(LV) || R.isInteresting(State->getRawSVal(LV))) |
| IE.insert(ArgE); |
| } |
| } |
| } |
| } |
| } |
| } |
| |
| //===----------------------------------------------------------------------===// |
| // Functions for determining if a loop was executed 0 times. |
| //===----------------------------------------------------------------------===// |
| |
| static bool isLoop(const Stmt *Term) { |
| switch (Term->getStmtClass()) { |
| case Stmt::ForStmtClass: |
| case Stmt::WhileStmtClass: |
| case Stmt::ObjCForCollectionStmtClass: |
| case Stmt::CXXForRangeStmtClass: |
| return true; |
| default: |
| // Note that we intentionally do not include do..while here. |
| return false; |
| } |
| } |
| |
| static bool isJumpToFalseBranch(const BlockEdge *BE) { |
| const CFGBlock *Src = BE->getSrc(); |
| assert(Src->succ_size() == 2); |
| return (*(Src->succ_begin()+1) == BE->getDst()); |
| } |
| |
| static bool isContainedByStmt(ParentMap &PM, const Stmt *S, const Stmt *SubS) { |
| while (SubS) { |
| if (SubS == S) |
| return true; |
| SubS = PM.getParent(SubS); |
| } |
| return false; |
| } |
| |
| static const Stmt *getStmtBeforeCond(ParentMap &PM, const Stmt *Term, |
| const ExplodedNode *N) { |
| while (N) { |
| Optional<StmtPoint> SP = N->getLocation().getAs<StmtPoint>(); |
| if (SP) { |
| const Stmt *S = SP->getStmt(); |
| if (!isContainedByStmt(PM, Term, S)) |
| return S; |
| } |
| N = N->getFirstPred(); |
| } |
| return nullptr; |
| } |
| |
| static bool isInLoopBody(ParentMap &PM, const Stmt *S, const Stmt *Term) { |
| const Stmt *LoopBody = nullptr; |
| switch (Term->getStmtClass()) { |
| case Stmt::CXXForRangeStmtClass: { |
| const auto *FR = cast<CXXForRangeStmt>(Term); |
| if (isContainedByStmt(PM, FR->getInc(), S)) |
| return true; |
| if (isContainedByStmt(PM, FR->getLoopVarStmt(), S)) |
| return true; |
| LoopBody = FR->getBody(); |
| break; |
| } |
| case Stmt::ForStmtClass: { |
| const auto *FS = cast<ForStmt>(Term); |
| if (isContainedByStmt(PM, FS->getInc(), S)) |
| return true; |
| LoopBody = FS->getBody(); |
| break; |
| } |
| case Stmt::ObjCForCollectionStmtClass: { |
| const auto *FC = cast<ObjCForCollectionStmt>(Term); |
| LoopBody = FC->getBody(); |
| break; |
| } |
| case Stmt::WhileStmtClass: |
| LoopBody = cast<WhileStmt>(Term)->getBody(); |
| break; |
| default: |
| return false; |
| } |
| return isContainedByStmt(PM, LoopBody, S); |
| } |
| |
| /// Adds a sanitized control-flow diagnostic edge to a path. |
| static void addEdgeToPath(PathPieces &path, |
| PathDiagnosticLocation &PrevLoc, |
| PathDiagnosticLocation NewLoc, |
| const LocationContext *LC) { |
| if (!NewLoc.isValid()) |
| return; |
| |
| SourceLocation NewLocL = NewLoc.asLocation(); |
| if (NewLocL.isInvalid()) |
| return; |
| |
| if (!PrevLoc.isValid() || !PrevLoc.asLocation().isValid()) { |
| PrevLoc = NewLoc; |
| return; |
| } |
| |
| // Ignore self-edges, which occur when there are multiple nodes at the same |
| // statement. |
| if (NewLoc.asStmt() && NewLoc.asStmt() == PrevLoc.asStmt()) |
| return; |
| |
| path.push_front( |
| std::make_shared<PathDiagnosticControlFlowPiece>(NewLoc, PrevLoc)); |
| PrevLoc = NewLoc; |
| } |
| |
| /// A customized wrapper for CFGBlock::getTerminatorCondition() |
| /// which returns the element for ObjCForCollectionStmts. |
| static const Stmt *getTerminatorCondition(const CFGBlock *B) { |
| const Stmt *S = B->getTerminatorCondition(); |
| if (const auto *FS = dyn_cast_or_null<ObjCForCollectionStmt>(S)) |
| return FS->getElement(); |
| return S; |
| } |
| |
| static const char StrEnteringLoop[] = "Entering loop body"; |
| static const char StrLoopBodyZero[] = "Loop body executed 0 times"; |
| static const char StrLoopRangeEmpty[] = |
| "Loop body skipped when range is empty"; |
| static const char StrLoopCollectionEmpty[] = |
| "Loop body skipped when collection is empty"; |
| |
| static std::unique_ptr<FilesToLineNumsMap> |
| findExecutedLines(SourceManager &SM, const ExplodedNode *N); |
| |
| /// Generate diagnostics for the node \p N, |
| /// and write it into \p PD. |
| /// \p AddPathEdges Whether diagnostic consumer can generate path arrows |
| /// showing both row and column. |
| static void generatePathDiagnosticsForNode(const ExplodedNode *N, |
| PathDiagnostic &PD, |
| PathDiagnosticLocation &PrevLoc, |
| PathDiagnosticBuilder &PDB, |
| LocationContextMap &LCM, |
| StackDiagVector &CallStack, |
| InterestingExprs &IE, |
| bool AddPathEdges) { |
| ProgramPoint P = N->getLocation(); |
| const SourceManager& SM = PDB.getSourceManager(); |
| |
| // Have we encountered an entrance to a call? It may be |
| // the case that we have not encountered a matching |
| // call exit before this point. This means that the path |
| // terminated within the call itself. |
| if (auto CE = P.getAs<CallEnter>()) { |
| |
| if (AddPathEdges) { |
| // Add an edge to the start of the function. |
| const StackFrameContext *CalleeLC = CE->getCalleeContext(); |
| const Decl *D = CalleeLC->getDecl(); |
| // Add the edge only when the callee has body. We jump to the beginning |
| // of the *declaration*, however we expect it to be followed by the |
| // body. This isn't the case for autosynthesized property accessors in |
| // Objective-C. No need for a similar extra check for CallExit points |
| // because the exit edge comes from a statement (i.e. return), |
| // not from declaration. |
| if (D->hasBody()) |
| addEdgeToPath(PD.getActivePath(), PrevLoc, |
| PathDiagnosticLocation::createBegin(D, SM), CalleeLC); |
| } |
| |
| // Did we visit an entire call? |
| bool VisitedEntireCall = PD.isWithinCall(); |
| PD.popActivePath(); |
| |
| PathDiagnosticCallPiece *C; |
| if (VisitedEntireCall) { |
| C = cast<PathDiagnosticCallPiece>(PD.getActivePath().front().get()); |
| } else { |
| const Decl *Caller = CE->getLocationContext()->getDecl(); |
| C = PathDiagnosticCallPiece::construct(PD.getActivePath(), Caller); |
| |
| if (AddPathEdges) { |
| // Since we just transferred the path over to the call piece, |
| // reset the mapping from active to location context. |
| assert(PD.getActivePath().size() == 1 && |
| PD.getActivePath().front().get() == C); |
| LCM[&PD.getActivePath()] = nullptr; |
| } |
| |
| // Record the location context mapping for the path within |
| // the call. |
| assert(LCM[&C->path] == nullptr || |
| LCM[&C->path] == CE->getCalleeContext()); |
| LCM[&C->path] = CE->getCalleeContext(); |
| |
| // If this is the first item in the active path, record |
| // the new mapping from active path to location context. |
| const LocationContext *&NewLC = LCM[&PD.getActivePath()]; |
| if (!NewLC) |
| NewLC = N->getLocationContext(); |
| |
| PDB.LC = NewLC; |
| } |
| C->setCallee(*CE, SM); |
| |
| // Update the previous location in the active path. |
| PrevLoc = C->getLocation(); |
| |
| if (!CallStack.empty()) { |
| assert(CallStack.back().first == C); |
| CallStack.pop_back(); |
| } |
| return; |
| } |
| |
| |
| if (AddPathEdges) { |
| // Query the location context here and the previous location |
| // as processing CallEnter may change the active path. |
| PDB.LC = N->getLocationContext(); |
| |
| // Record the mapping from the active path to the location |
| // context. |
| assert(!LCM[&PD.getActivePath()] || LCM[&PD.getActivePath()] == PDB.LC); |
| LCM[&PD.getActivePath()] = PDB.LC; |
| } |
| |
| // Have we encountered an exit from a function call? |
| if (Optional<CallExitEnd> CE = P.getAs<CallExitEnd>()) { |
| |
| // We are descending into a call (backwards). Construct |
| // a new call piece to contain the path pieces for that call. |
| auto C = PathDiagnosticCallPiece::construct(N, *CE, SM); |
| // Record the mapping from call piece to LocationContext. |
| LCM[&C->path] = CE->getCalleeContext(); |
| |
| if (AddPathEdges) { |
| const Stmt *S = CE->getCalleeContext()->getCallSite(); |
| // Propagate the interesting symbols accordingly. |
| if (const auto *Ex = dyn_cast_or_null<Expr>(S)) { |
| reversePropagateIntererstingSymbols(*PDB.getBugReport(), IE, |
| N->getState().get(), Ex, |
| N->getLocationContext()); |
| } |
| // Add the edge to the return site. |
| addEdgeToPath(PD.getActivePath(), PrevLoc, C->callReturn, PDB.LC); |
| PrevLoc.invalidate(); |
| } |
| |
| auto *P = C.get(); |
| PD.getActivePath().push_front(std::move(C)); |
| |
| // Make the contents of the call the active path for now. |
| PD.pushActivePath(&P->path); |
| CallStack.push_back(StackDiagPair(P, N)); |
| return; |
| } |
| |
| if (auto PS = P.getAs<PostStmt>()) { |
| if (!AddPathEdges) |
| return; |
| |
| // For expressions, make sure we propagate the |
| // interesting symbols correctly. |
| if (const Expr *Ex = PS->getStmtAs<Expr>()) |
| reversePropagateIntererstingSymbols(*PDB.getBugReport(), IE, |
| N->getState().get(), Ex, |
| N->getLocationContext()); |
| |
| // Add an edge. If this is an ObjCForCollectionStmt do |
| // not add an edge here as it appears in the CFG both |
| // as a terminator and as a terminator condition. |
| if (!isa<ObjCForCollectionStmt>(PS->getStmt())) { |
| PathDiagnosticLocation L = |
| PathDiagnosticLocation(PS->getStmt(), SM, PDB.LC); |
| addEdgeToPath(PD.getActivePath(), PrevLoc, L, PDB.LC); |
| } |
| |
| } else if (auto BE = P.getAs<BlockEdge>()) { |
| |
| if (!AddPathEdges) { |
| generateMinimalDiagForBlockEdge(N, *BE, SM, PDB, PD); |
| return; |
| } |
| |
| // Does this represent entering a call? If so, look at propagating |
| // interesting symbols across call boundaries. |
| if (const ExplodedNode *NextNode = N->getFirstPred()) { |
| const LocationContext *CallerCtx = NextNode->getLocationContext(); |
| const LocationContext *CalleeCtx = PDB.LC; |
| if (CallerCtx != CalleeCtx && AddPathEdges) { |
| reversePropagateInterestingSymbols(*PDB.getBugReport(), IE, |
| N->getState().get(), |
| CalleeCtx, CallerCtx); |
| } |
| } |
| |
| // Are we jumping to the head of a loop? Add a special diagnostic. |
| if (const Stmt *Loop = BE->getSrc()->getLoopTarget()) { |
| PathDiagnosticLocation L(Loop, SM, PDB.LC); |
| const Stmt *Body = nullptr; |
| |
| if (const auto *FS = dyn_cast<ForStmt>(Loop)) |
| Body = FS->getBody(); |
| else if (const auto *WS = dyn_cast<WhileStmt>(Loop)) |
| Body = WS->getBody(); |
| else if (const auto *OFS = dyn_cast<ObjCForCollectionStmt>(Loop)) { |
| Body = OFS->getBody(); |
| } else if (const auto *FRS = dyn_cast<CXXForRangeStmt>(Loop)) { |
| Body = FRS->getBody(); |
| } |
| // do-while statements are explicitly excluded here |
| |
| auto p = std::make_shared<PathDiagnosticEventPiece>( |
| L, "Looping back to the head " |
| "of the loop"); |
| p->setPrunable(true); |
| |
| addEdgeToPath(PD.getActivePath(), PrevLoc, p->getLocation(), PDB.LC); |
| PD.getActivePath().push_front(std::move(p)); |
| |
| if (const auto *CS = dyn_cast_or_null<CompoundStmt>(Body)) { |
| addEdgeToPath(PD.getActivePath(), PrevLoc, |
| PathDiagnosticLocation::createEndBrace(CS, SM), |
| PDB.LC); |
| } |
| } |
| |
| const CFGBlock *BSrc = BE->getSrc(); |
| ParentMap &PM = PDB.getParentMap(); |
| |
| if (const Stmt *Term = BSrc->getTerminator()) { |
| // Are we jumping past the loop body without ever executing the |
| // loop (because the condition was false)? |
| if (isLoop(Term)) { |
| const Stmt *TermCond = getTerminatorCondition(BSrc); |
| bool IsInLoopBody = |
| isInLoopBody(PM, getStmtBeforeCond(PM, TermCond, N), Term); |
| |
| const char *str = nullptr; |
| |
| if (isJumpToFalseBranch(&*BE)) { |
| if (!IsInLoopBody) { |
| if (isa<ObjCForCollectionStmt>(Term)) { |
| str = StrLoopCollectionEmpty; |
| } else if (isa<CXXForRangeStmt>(Term)) { |
| str = StrLoopRangeEmpty; |
| } else { |
| str = StrLoopBodyZero; |
| } |
| } |
| } else { |
| str = StrEnteringLoop; |
| } |
| |
| if (str) { |
| PathDiagnosticLocation L(TermCond ? TermCond : Term, SM, PDB.LC); |
| auto PE = std::make_shared<PathDiagnosticEventPiece>(L, str); |
| PE->setPrunable(true); |
| addEdgeToPath(PD.getActivePath(), PrevLoc, |
| PE->getLocation(), PDB.LC); |
| PD.getActivePath().push_front(std::move(PE)); |
| } |
| } else if (isa<BreakStmt>(Term) || isa<ContinueStmt>(Term) || |
| isa<GotoStmt>(Term)) { |
| PathDiagnosticLocation L(Term, SM, PDB.LC); |
| addEdgeToPath(PD.getActivePath(), PrevLoc, L, PDB.LC); |
| } |
| } |
| } |
| } |
| |
| static std::unique_ptr<PathDiagnostic> |
| generateEmptyDiagnosticForReport(BugReport *R, SourceManager &SM) { |
| BugType &BT = R->getBugType(); |
| return llvm::make_unique<PathDiagnostic>( |
| R->getBugType().getCheckName(), R->getDeclWithIssue(), |
| R->getBugType().getName(), R->getDescription(), |
| R->getShortDescription(/*Fallback=*/false), BT.getCategory(), |
| R->getUniqueingLocation(), R->getUniqueingDecl(), |
| findExecutedLines(SM, R->getErrorNode())); |
| } |
| |
| static const Stmt *getStmtParent(const Stmt *S, const ParentMap &PM) { |
| if (!S) |
| return nullptr; |
| |
| while (true) { |
| S = PM.getParentIgnoreParens(S); |
| |
| if (!S) |
| break; |
| |
| if (isa<ExprWithCleanups>(S) || |
| isa<CXXBindTemporaryExpr>(S) || |
| isa<SubstNonTypeTemplateParmExpr>(S)) |
| continue; |
| |
| break; |
| } |
| |
| return S; |
| } |
| |
| static bool isConditionForTerminator(const Stmt *S, const Stmt *Cond) { |
| switch (S->getStmtClass()) { |
| case Stmt::BinaryOperatorClass: { |
| const auto *BO = cast<BinaryOperator>(S); |
| if (!BO->isLogicalOp()) |
| return false; |
| return BO->getLHS() == Cond || BO->getRHS() == Cond; |
| } |
| case Stmt::IfStmtClass: |
| return cast<IfStmt>(S)->getCond() == Cond; |
| case Stmt::ForStmtClass: |
| return cast<ForStmt>(S)->getCond() == Cond; |
| case Stmt::WhileStmtClass: |
| return cast<WhileStmt>(S)->getCond() == Cond; |
| case Stmt::DoStmtClass: |
| return cast<DoStmt>(S)->getCond() == Cond; |
| case Stmt::ChooseExprClass: |
| return cast<ChooseExpr>(S)->getCond() == Cond; |
| case Stmt::IndirectGotoStmtClass: |
| return cast<IndirectGotoStmt>(S)->getTarget() == Cond; |
| case Stmt::SwitchStmtClass: |
| return cast<SwitchStmt>(S)->getCond() == Cond; |
| case Stmt::BinaryConditionalOperatorClass: |
| return cast<BinaryConditionalOperator>(S)->getCond() == Cond; |
| case Stmt::ConditionalOperatorClass: { |
| const auto *CO = cast<ConditionalOperator>(S); |
| return CO->getCond() == Cond || |
| CO->getLHS() == Cond || |
| CO->getRHS() == Cond; |
| } |
| case Stmt::ObjCForCollectionStmtClass: |
| return cast<ObjCForCollectionStmt>(S)->getElement() == Cond; |
| case Stmt::CXXForRangeStmtClass: { |
| const auto *FRS = cast<CXXForRangeStmt>(S); |
| return FRS->getCond() == Cond || FRS->getRangeInit() == Cond; |
| } |
| default: |
| return false; |
| } |
| } |
| |
| static bool isIncrementOrInitInForLoop(const Stmt *S, const Stmt *FL) { |
| if (const auto *FS = dyn_cast<ForStmt>(FL)) |
| return FS->getInc() == S || FS->getInit() == S; |
| if (const auto *FRS = dyn_cast<CXXForRangeStmt>(FL)) |
| return FRS->getInc() == S || FRS->getRangeStmt() == S || |
| FRS->getLoopVarStmt() || FRS->getRangeInit() == S; |
| return false; |
| } |
| |
| using OptimizedCallsSet = llvm::DenseSet<const PathDiagnosticCallPiece *>; |
| |
| /// Adds synthetic edges from top-level statements to their subexpressions. |
| /// |
| /// This avoids a "swoosh" effect, where an edge from a top-level statement A |
| /// points to a sub-expression B.1 that's not at the start of B. In these cases, |
| /// we'd like to see an edge from A to B, then another one from B to B.1. |
| static void addContextEdges(PathPieces &pieces, SourceManager &SM, |
| const ParentMap &PM, const LocationContext *LCtx) { |
| PathPieces::iterator Prev = pieces.end(); |
| for (PathPieces::iterator I = pieces.begin(), E = Prev; I != E; |
| Prev = I, ++I) { |
| auto *Piece = dyn_cast<PathDiagnosticControlFlowPiece>(I->get()); |
| |
| if (!Piece) |
| continue; |
| |
| PathDiagnosticLocation SrcLoc = Piece->getStartLocation(); |
| SmallVector<PathDiagnosticLocation, 4> SrcContexts; |
| |
| PathDiagnosticLocation NextSrcContext = SrcLoc; |
| const Stmt *InnerStmt = nullptr; |
| while (NextSrcContext.isValid() && NextSrcContext.asStmt() != InnerStmt) { |
| SrcContexts.push_back(NextSrcContext); |
| InnerStmt = NextSrcContext.asStmt(); |
| NextSrcContext = getEnclosingStmtLocation(InnerStmt, SM, PM, LCtx, |
| /*allowNested=*/true); |
| } |
| |
| // Repeatedly split the edge as necessary. |
| // This is important for nested logical expressions (||, &&, ?:) where we |
| // want to show all the levels of context. |
| while (true) { |
| const Stmt *Dst = Piece->getEndLocation().getStmtOrNull(); |
| |
| // We are looking at an edge. Is the destination within a larger |
| // expression? |
| PathDiagnosticLocation DstContext = |
| getEnclosingStmtLocation(Dst, SM, PM, LCtx, /*allowNested=*/true); |
| if (!DstContext.isValid() || DstContext.asStmt() == Dst) |
| break; |
| |
| // If the source is in the same context, we're already good. |
| if (std::find(SrcContexts.begin(), SrcContexts.end(), DstContext) != |
| SrcContexts.end()) |
| break; |
| |
| // Update the subexpression node to point to the context edge. |
| Piece->setStartLocation(DstContext); |
| |
| // Try to extend the previous edge if it's at the same level as the source |
| // context. |
| if (Prev != E) { |
| auto *PrevPiece = dyn_cast<PathDiagnosticControlFlowPiece>(Prev->get()); |
| |
| if (PrevPiece) { |
| if (const Stmt *PrevSrc = |
| PrevPiece->getStartLocation().getStmtOrNull()) { |
| const Stmt *PrevSrcParent = getStmtParent(PrevSrc, PM); |
| if (PrevSrcParent == |
| getStmtParent(DstContext.getStmtOrNull(), PM)) { |
| PrevPiece->setEndLocation(DstContext); |
| break; |
| } |
| } |
| } |
| } |
| |
| // Otherwise, split the current edge into a context edge and a |
| // subexpression edge. Note that the context statement may itself have |
| // context. |
| auto P = |
| std::make_shared<PathDiagnosticControlFlowPiece>(SrcLoc, DstContext); |
| Piece = P.get(); |
| I = pieces.insert(I, std::move(P)); |
| } |
| } |
| } |
| |
| /// Move edges from a branch condition to a branch target |
| /// when the condition is simple. |
| /// |
| /// This restructures some of the work of addContextEdges. That function |
| /// creates edges this may destroy, but they work together to create a more |
| /// aesthetically set of edges around branches. After the call to |
| /// addContextEdges, we may have (1) an edge to the branch, (2) an edge from |
| /// the branch to the branch condition, and (3) an edge from the branch |
| /// condition to the branch target. We keep (1), but may wish to remove (2) |
| /// and move the source of (3) to the branch if the branch condition is simple. |
| static void simplifySimpleBranches(PathPieces &pieces) { |
| for (PathPieces::iterator I = pieces.begin(), E = pieces.end(); I != E; ++I) { |
| const auto *PieceI = dyn_cast<PathDiagnosticControlFlowPiece>(I->get()); |
| |
| if (!PieceI) |
| continue; |
| |
| const Stmt *s1Start = PieceI->getStartLocation().getStmtOrNull(); |
| const Stmt *s1End = PieceI->getEndLocation().getStmtOrNull(); |
| |
| if (!s1Start || !s1End) |
| continue; |
| |
| PathPieces::iterator NextI = I; ++NextI; |
| if (NextI == E) |
| break; |
| |
| PathDiagnosticControlFlowPiece *PieceNextI = nullptr; |
| |
| while (true) { |
| if (NextI == E) |
| break; |
| |
| const auto *EV = dyn_cast<PathDiagnosticEventPiece>(NextI->get()); |
| if (EV) { |
| StringRef S = EV->getString(); |
| if (S == StrEnteringLoop || S == StrLoopBodyZero || |
| S == StrLoopCollectionEmpty || S == StrLoopRangeEmpty) { |
| ++NextI; |
| continue; |
| } |
| break; |
| } |
| |
| PieceNextI = dyn_cast<PathDiagnosticControlFlowPiece>(NextI->get()); |
| break; |
| } |
| |
| if (!PieceNextI) |
| continue; |
| |
| const Stmt *s2Start = PieceNextI->getStartLocation().getStmtOrNull(); |
| const Stmt *s2End = PieceNextI->getEndLocation().getStmtOrNull(); |
| |
| if (!s2Start || !s2End || s1End != s2Start) |
| continue; |
| |
| // We only perform this transformation for specific branch kinds. |
| // We don't want to do this for do..while, for example. |
| if (!(isa<ForStmt>(s1Start) || isa<WhileStmt>(s1Start) || |
| isa<IfStmt>(s1Start) || isa<ObjCForCollectionStmt>(s1Start) || |
| isa<CXXForRangeStmt>(s1Start))) |
| continue; |
| |
| // Is s1End the branch condition? |
| if (!isConditionForTerminator(s1Start, s1End)) |
| continue; |
| |
| // Perform the hoisting by eliminating (2) and changing the start |
| // location of (3). |
| PieceNextI->setStartLocation(PieceI->getStartLocation()); |
| I = pieces.erase(I); |
| } |
| } |
| |
| /// Returns the number of bytes in the given (character-based) SourceRange. |
| /// |
| /// If the locations in the range are not on the same line, returns None. |
| /// |
| /// Note that this does not do a precise user-visible character or column count. |
| static Optional<size_t> getLengthOnSingleLine(SourceManager &SM, |
| SourceRange Range) { |
| SourceRange ExpansionRange(SM.getExpansionLoc(Range.getBegin()), |
| SM.getExpansionRange(Range.getEnd()).getEnd()); |
| |
| FileID FID = SM.getFileID(ExpansionRange.getBegin()); |
| if (FID != SM.getFileID(ExpansionRange.getEnd())) |
| return None; |
| |
| bool Invalid; |
| const llvm::MemoryBuffer *Buffer = SM.getBuffer(FID, &Invalid); |
| if (Invalid) |
| return None; |
| |
| unsigned BeginOffset = SM.getFileOffset(ExpansionRange.getBegin()); |
| unsigned EndOffset = SM.getFileOffset(ExpansionRange.getEnd()); |
| StringRef Snippet = Buffer->getBuffer().slice(BeginOffset, EndOffset); |
| |
| // We're searching the raw bytes of the buffer here, which might include |
| // escaped newlines and such. That's okay; we're trying to decide whether the |
| // SourceRange is covering a large or small amount of space in the user's |
| // editor. |
| if (Snippet.find_first_of("\r\n") != StringRef::npos) |
| return None; |
| |
| // This isn't Unicode-aware, but it doesn't need to be. |
| return Snippet.size(); |
| } |
| |
| /// \sa getLengthOnSingleLine(SourceManager, SourceRange) |
| static Optional<size_t> getLengthOnSingleLine(SourceManager &SM, |
| const Stmt *S) { |
| return getLengthOnSingleLine(SM, S->getSourceRange()); |
| } |
| |
| /// Eliminate two-edge cycles created by addContextEdges(). |
| /// |
| /// Once all the context edges are in place, there are plenty of cases where |
| /// there's a single edge from a top-level statement to a subexpression, |
| /// followed by a single path note, and then a reverse edge to get back out to |
| /// the top level. If the statement is simple enough, the subexpression edges |
| /// just add noise and make it harder to understand what's going on. |
| /// |
| /// This function only removes edges in pairs, because removing only one edge |
| /// might leave other edges dangling. |
| /// |
| /// This will not remove edges in more complicated situations: |
| /// - if there is more than one "hop" leading to or from a subexpression. |
| /// - if there is an inlined call between the edges instead of a single event. |
| /// - if the whole statement is large enough that having subexpression arrows |
| /// might be helpful. |
| static void removeContextCycles(PathPieces &Path, SourceManager &SM, |
| ParentMap &PM) { |
| for (PathPieces::iterator I = Path.begin(), E = Path.end(); I != E; ) { |
| // Pattern match the current piece and its successor. |
| const auto *PieceI = dyn_cast<PathDiagnosticControlFlowPiece>(I->get()); |
| |
| if (!PieceI) { |
| ++I; |
| continue; |
| } |
| |
| const Stmt *s1Start = PieceI->getStartLocation().getStmtOrNull(); |
| const Stmt *s1End = PieceI->getEndLocation().getStmtOrNull(); |
| |
| PathPieces::iterator NextI = I; ++NextI; |
| if (NextI == E) |
| break; |
| |
| const auto *PieceNextI = |
| dyn_cast<PathDiagnosticControlFlowPiece>(NextI->get()); |
| |
| if (!PieceNextI) { |
| if (isa<PathDiagnosticEventPiece>(NextI->get())) { |
| ++NextI; |
| if (NextI == E) |
| break; |
| PieceNextI = dyn_cast<PathDiagnosticControlFlowPiece>(NextI->get()); |
| } |
| |
| if (!PieceNextI) { |
| ++I; |
| continue; |
| } |
| } |
| |
| const Stmt *s2Start = PieceNextI->getStartLocation().getStmtOrNull(); |
| const Stmt *s2End = PieceNextI->getEndLocation().getStmtOrNull(); |
| |
| if (s1Start && s2Start && s1Start == s2End && s2Start == s1End) { |
| const size_t MAX_SHORT_LINE_LENGTH = 80; |
| Optional<size_t> s1Length = getLengthOnSingleLine(SM, s1Start); |
| if (s1Length && *s1Length <= MAX_SHORT_LINE_LENGTH) { |
| Optional<size_t> s2Length = getLengthOnSingleLine(SM, s2Start); |
| if (s2Length && *s2Length <= MAX_SHORT_LINE_LENGTH) { |
| Path.erase(I); |
| I = Path.erase(NextI); |
| continue; |
| } |
| } |
| } |
| |
| ++I; |
| } |
| } |
| |
| /// Return true if X is contained by Y. |
| static bool lexicalContains(ParentMap &PM, const Stmt *X, const Stmt *Y) { |
| while (X) { |
| if (X == Y) |
| return true; |
| X = PM.getParent(X); |
| } |
| return false; |
| } |
| |
| // Remove short edges on the same line less than 3 columns in difference. |
| static void removePunyEdges(PathPieces &path, SourceManager &SM, |
| ParentMap &PM) { |
| bool erased = false; |
| |
| for (PathPieces::iterator I = path.begin(), E = path.end(); I != E; |
| erased ? I : ++I) { |
| erased = false; |
| |
| const auto *PieceI = dyn_cast<PathDiagnosticControlFlowPiece>(I->get()); |
| |
| if (!PieceI) |
| continue; |
| |
| const Stmt *start = PieceI->getStartLocation().getStmtOrNull(); |
| const Stmt *end = PieceI->getEndLocation().getStmtOrNull(); |
| |
| if (!start || !end) |
| continue; |
| |
| const Stmt *endParent = PM.getParent(end); |
| if (!endParent) |
| continue; |
| |
| if (isConditionForTerminator(end, endParent)) |
| continue; |
| |
| SourceLocation FirstLoc = start->getLocStart(); |
| SourceLocation SecondLoc = end->getLocStart(); |
| |
| if (!SM.isWrittenInSameFile(FirstLoc, SecondLoc)) |
| continue; |
| if (SM.isBeforeInTranslationUnit(SecondLoc, FirstLoc)) |
| std::swap(SecondLoc, FirstLoc); |
| |
| SourceRange EdgeRange(FirstLoc, SecondLoc); |
| Optional<size_t> ByteWidth = getLengthOnSingleLine(SM, EdgeRange); |
| |
| // If the statements are on different lines, continue. |
| if (!ByteWidth) |
| continue; |
| |
| const size_t MAX_PUNY_EDGE_LENGTH = 2; |
| if (*ByteWidth <= MAX_PUNY_EDGE_LENGTH) { |
| // FIXME: There are enough /bytes/ between the endpoints of the edge, but |
| // there might not be enough /columns/. A proper user-visible column count |
| // is probably too expensive, though. |
| I = path.erase(I); |
| erased = true; |
| continue; |
| } |
| } |
| } |
| |
| static void removeIdenticalEvents(PathPieces &path) { |
| for (PathPieces::iterator I = path.begin(), E = path.end(); I != E; ++I) { |
| const auto *PieceI = dyn_cast<PathDiagnosticEventPiece>(I->get()); |
| |
| if (!PieceI) |
| continue; |
| |
| PathPieces::iterator NextI = I; ++NextI; |
| if (NextI == E) |
| return; |
| |
| const auto *PieceNextI = dyn_cast<PathDiagnosticEventPiece>(NextI->get()); |
| |
| if (!PieceNextI) |
| continue; |
| |
| // Erase the second piece if it has the same exact message text. |
| if (PieceI->getString() == PieceNextI->getString()) { |
| path.erase(NextI); |
| } |
| } |
| } |
| |
| static bool optimizeEdges(PathPieces &path, SourceManager &SM, |
| OptimizedCallsSet &OCS, |
| LocationContextMap &LCM) { |
| bool hasChanges = false; |
| const LocationContext *LC = LCM[&path]; |
| assert(LC); |
| ParentMap &PM = LC->getParentMap(); |
| |
| for (PathPieces::iterator I = path.begin(), E = path.end(); I != E; ) { |
| // Optimize subpaths. |
| if (auto *CallI = dyn_cast<PathDiagnosticCallPiece>(I->get())) { |
| // Record the fact that a call has been optimized so we only do the |
| // effort once. |
| if (!OCS.count(CallI)) { |
| while (optimizeEdges(CallI->path, SM, OCS, LCM)) {} |
| OCS.insert(CallI); |
| } |
| ++I; |
| continue; |
| } |
| |
| // Pattern match the current piece and its successor. |
| auto *PieceI = dyn_cast<PathDiagnosticControlFlowPiece>(I->get()); |
| |
| if (!PieceI) { |
| ++I; |
| continue; |
| } |
| |
| const Stmt *s1Start = PieceI->getStartLocation().getStmtOrNull(); |
| const Stmt *s1End = PieceI->getEndLocation().getStmtOrNull(); |
| const Stmt *level1 = getStmtParent(s1Start, PM); |
| const Stmt *level2 = getStmtParent(s1End, PM); |
| |
| PathPieces::iterator NextI = I; ++NextI; |
| if (NextI == E) |
| break; |
| |
| const auto *PieceNextI = dyn_cast<PathDiagnosticControlFlowPiece>(NextI->get()); |
| |
| if (!PieceNextI) { |
| ++I; |
| continue; |
| } |
| |
| const Stmt *s2Start = PieceNextI->getStartLocation().getStmtOrNull(); |
| const Stmt *s2End = PieceNextI->getEndLocation().getStmtOrNull(); |
| const Stmt *level3 = getStmtParent(s2Start, PM); |
| const Stmt *level4 = getStmtParent(s2End, PM); |
| |
| // Rule I. |
| // |
| // If we have two consecutive control edges whose end/begin locations |
| // are at the same level (e.g. statements or top-level expressions within |
| // a compound statement, or siblings share a single ancestor expression), |
| // then merge them if they have no interesting intermediate event. |
| // |
| // For example: |
| // |
| // (1.1 -> 1.2) -> (1.2 -> 1.3) becomes (1.1 -> 1.3) because the common |
| // parent is '1'. Here 'x.y.z' represents the hierarchy of statements. |
| // |
| // NOTE: this will be limited later in cases where we add barriers |
| // to prevent this optimization. |
| if (level1 && level1 == level2 && level1 == level3 && level1 == level4) { |
| PieceI->setEndLocation(PieceNextI->getEndLocation()); |
| path.erase(NextI); |
| hasChanges = true; |
| continue; |
| } |
| |
| // Rule II. |
| // |
| // Eliminate edges between subexpressions and parent expressions |
| // when the subexpression is consumed. |
| // |
| // NOTE: this will be limited later in cases where we add barriers |
| // to prevent this optimization. |
| if (s1End && s1End == s2Start && level2) { |
| bool removeEdge = false; |
| // Remove edges into the increment or initialization of a |
| // loop that have no interleaving event. This means that |
| // they aren't interesting. |
| if (isIncrementOrInitInForLoop(s1End, level2)) |
| removeEdge = true; |
| // Next only consider edges that are not anchored on |
| // the condition of a terminator. This are intermediate edges |
| // that we might want to trim. |
| else if (!isConditionForTerminator(level2, s1End)) { |
| // Trim edges on expressions that are consumed by |
| // the parent expression. |
| if (isa<Expr>(s1End) && PM.isConsumedExpr(cast<Expr>(s1End))) { |
| removeEdge = true; |
| } |
| // Trim edges where a lexical containment doesn't exist. |
| // For example: |
| // |
| // X -> Y -> Z |
| // |
| // If 'Z' lexically contains Y (it is an ancestor) and |
| // 'X' does not lexically contain Y (it is a descendant OR |
| // it has no lexical relationship at all) then trim. |
| // |
| // This can eliminate edges where we dive into a subexpression |
| // and then pop back out, etc. |
| else if (s1Start && s2End && |
| lexicalContains(PM, s2Start, s2End) && |
| !lexicalContains(PM, s1End, s1Start)) { |
| removeEdge = true; |
| } |
| // Trim edges from a subexpression back to the top level if the |
| // subexpression is on a different line. |
| // |
| // A.1 -> A -> B |
| // becomes |
| // A.1 -> B |
| // |
| // These edges just look ugly and don't usually add anything. |
| else if (s1Start && s2End && |
| lexicalContains(PM, s1Start, s1End)) { |
| SourceRange EdgeRange(PieceI->getEndLocation().asLocation(), |
| PieceI->getStartLocation().asLocation()); |
| if (!getLengthOnSingleLine(SM, EdgeRange).hasValue()) |
| removeEdge = true; |
| } |
| } |
| |
| if (removeEdge) { |
| PieceI->setEndLocation(PieceNextI->getEndLocation()); |
| path.erase(NextI); |
| hasChanges = true; |
| continue; |
| } |
| } |
| |
| // Optimize edges for ObjC fast-enumeration loops. |
| // |
| // (X -> collection) -> (collection -> element) |
| // |
| // becomes: |
| // |
| // (X -> element) |
| if (s1End == s2Start) { |
| const auto *FS = dyn_cast_or_null<ObjCForCollectionStmt>(level3); |
| if (FS && FS->getCollection()->IgnoreParens() == s2Start && |
| s2End == FS->getElement()) { |
| PieceI->setEndLocation(PieceNextI->getEndLocation()); |
| path.erase(NextI); |
| hasChanges = true; |
| continue; |
| } |
| } |
| |
| // No changes at this index? Move to the next one. |
| ++I; |
| } |
| |
| if (!hasChanges) { |
| // Adjust edges into subexpressions to make them more uniform |
| // and aesthetically pleasing. |
| addContextEdges(path, SM, PM, LC); |
| // Remove "cyclical" edges that include one or more context edges. |
| removeContextCycles(path, SM, PM); |
| // Hoist edges originating from branch conditions to branches |
| // for simple branches. |
| simplifySimpleBranches(path); |
| // Remove any puny edges left over after primary optimization pass. |
| removePunyEdges(path, SM, PM); |
| // Remove identical events. |
| removeIdenticalEvents(path); |
| } |
| |
| return hasChanges; |
| } |
| |
| /// Drop the very first edge in a path, which should be a function entry edge. |
| /// |
| /// If the first edge is not a function entry edge (say, because the first |
| /// statement had an invalid source location), this function does nothing. |
| // FIXME: We should just generate invalid edges anyway and have the optimizer |
| // deal with them. |
| static void dropFunctionEntryEdge(PathPieces &Path, LocationContextMap &LCM, |
| SourceManager &SM) { |
| const auto *FirstEdge = |
| dyn_cast<PathDiagnosticControlFlowPiece>(Path.front().get()); |
| if (!FirstEdge) |
| return; |
| |
| const Decl *D = LCM[&Path]->getDecl(); |
| PathDiagnosticLocation EntryLoc = PathDiagnosticLocation::createBegin(D, SM); |
| if (FirstEdge->getStartLocation() != EntryLoc) |
| return; |
| |
| Path.pop_front(); |
| } |
| |
| using VisitorsDiagnosticsTy = llvm::DenseMap<const ExplodedNode *, |
| std::vector<std::shared_ptr<PathDiagnosticPiece>>>; |
| |
| /// This function is responsible for generating diagnostic pieces that are |
| /// *not* provided by bug report visitors. |
| /// These diagnostics may differ depending on the consumer's settings, |
| /// and are therefore constructed separately for each consumer. |
| /// |
| /// There are two path diagnostics generation modes: with adding edges (used |
| /// for plists) and without (used for HTML and text). |
| /// When edges are added (\p ActiveScheme is Extensive), |
| /// the path is modified to insert artificially generated |
| /// edges. |
| /// Otherwise, more detailed diagnostics is emitted for block edges, explaining |
| /// the transitions in words. |
| static std::unique_ptr<PathDiagnostic> generatePathDiagnosticForConsumer( |
| PathDiagnosticConsumer::PathGenerationScheme ActiveScheme, |
| PathDiagnosticBuilder &PDB, |
| const ExplodedNode *ErrorNode, |
| const VisitorsDiagnosticsTy &VisitorsDiagnostics) { |
| |
| bool GenerateDiagnostics = (ActiveScheme != PathDiagnosticConsumer::None); |
| bool AddPathEdges = (ActiveScheme == PathDiagnosticConsumer::Extensive); |
| SourceManager &SM = PDB.getSourceManager(); |
| BugReport *R = PDB.getBugReport(); |
| AnalyzerOptions &Opts = PDB.getBugReporter().getAnalyzerOptions(); |
| StackDiagVector CallStack; |
| InterestingExprs IE; |
| LocationContextMap LCM; |
| std::unique_ptr<PathDiagnostic> PD = generateEmptyDiagnosticForReport(R, SM); |
| |
| if (GenerateDiagnostics) { |
| auto EndNotes = VisitorsDiagnostics.find(ErrorNode); |
| std::shared_ptr<PathDiagnosticPiece> LastPiece; |
| if (EndNotes != VisitorsDiagnostics.end()) { |
| assert(!EndNotes->second.empty()); |
| LastPiece = EndNotes->second[0]; |
| } else { |
| LastPiece = BugReporterVisitor::getDefaultEndPath(PDB, ErrorNode, *R); |
| } |
| PD->setEndOfPath(LastPiece); |
| } |
| |
| PathDiagnosticLocation PrevLoc = PD->getLocation(); |
| const ExplodedNode *NextNode = ErrorNode->getFirstPred(); |
| while (NextNode) { |
| if (GenerateDiagnostics) |
| generatePathDiagnosticsForNode( |
| NextNode, *PD, PrevLoc, PDB, LCM, CallStack, IE, AddPathEdges); |
| |
| auto VisitorNotes = VisitorsDiagnostics.find(NextNode); |
| NextNode = NextNode->getFirstPred(); |
| if (!GenerateDiagnostics || VisitorNotes == VisitorsDiagnostics.end()) |
| continue; |
| |
| // This is a workaround due to inability to put shared PathDiagnosticPiece |
| // into a FoldingSet. |
| std::set<llvm::FoldingSetNodeID> DeduplicationSet; |
| |
| // Add pieces from custom visitors. |
| for (const auto &Note : VisitorNotes->second) { |
| llvm::FoldingSetNodeID ID; |
| Note->Profile(ID); |
| auto P = DeduplicationSet.insert(ID); |
| if (!P.second) |
| continue; |
| |
| if (AddPathEdges) |
| addEdgeToPath(PD->getActivePath(), PrevLoc, Note->getLocation(), |
| PDB.LC); |
| updateStackPiecesWithMessage(*Note, CallStack); |
| PD->getActivePath().push_front(Note); |
| } |
| } |
| |
| if (AddPathEdges) { |
| // Add an edge to the start of the function. |
| // We'll prune it out later, but it helps make diagnostics more uniform. |
| const StackFrameContext *CalleeLC = PDB.LC->getStackFrame(); |
| const Decl *D = CalleeLC->getDecl(); |
| addEdgeToPath(PD->getActivePath(), PrevLoc, |
| PathDiagnosticLocation::createBegin(D, SM), CalleeLC); |
| } |
| |
| if (!AddPathEdges && GenerateDiagnostics) |
| CompactPathDiagnostic(PD->getMutablePieces(), SM); |
| |
| // Finally, prune the diagnostic path of uninteresting stuff. |
| if (!PD->path.empty()) { |
| if (R->shouldPrunePath() && Opts.shouldPrunePaths()) { |
| bool stillHasNotes = |
| removeUnneededCalls(PD->getMutablePieces(), R, LCM); |
| assert(stillHasNotes); |
| (void)stillHasNotes; |
| } |
| |
| // Redirect all call pieces to have valid locations. |
| adjustCallLocations(PD->getMutablePieces()); |
| removePiecesWithInvalidLocations(PD->getMutablePieces()); |
| |
| if (AddPathEdges) { |
| |
| // Reduce the number of edges from a very conservative set |
| // to an aesthetically pleasing subset that conveys the |
| // necessary information. |
| OptimizedCallsSet OCS; |
| while (optimizeEdges(PD->getMutablePieces(), SM, OCS, LCM)) {} |
| |
| // Drop the very first function-entry edge. It's not really necessary |
| // for top-level functions. |
| dropFunctionEntryEdge(PD->getMutablePieces(), LCM, SM); |
| } |
| |
| // Remove messages that are basically the same, and edges that may not |
| // make sense. |
| // We have to do this after edge optimization in the Extensive mode. |
| removeRedundantMsgs(PD->getMutablePieces()); |
| removeEdgesToDefaultInitializers(PD->getMutablePieces()); |
| } |
| return PD; |
| } |
| |
| |
| //===----------------------------------------------------------------------===// |
| // Methods for BugType and subclasses. |
| //===----------------------------------------------------------------------===// |
| |
| void BugType::anchor() {} |
| |
| void BugType::FlushReports(BugReporter &BR) {} |
| |
| void BuiltinBug::anchor() {} |
| |
| //===----------------------------------------------------------------------===// |
| // Methods for BugReport and subclasses. |
| //===----------------------------------------------------------------------===// |
| |
| void BugReport::NodeResolver::anchor() {} |
| |
| void BugReport::addVisitor(std::unique_ptr<BugReporterVisitor> visitor) { |
| if (!visitor) |
| return; |
| |
| llvm::FoldingSetNodeID ID; |
| visitor->Profile(ID); |
| |
| void *InsertPos = nullptr; |
| if (CallbacksSet.FindNodeOrInsertPos(ID, InsertPos)) { |
| return; |
| } |
| |
| Callbacks.push_back(std::move(visitor)); |
| } |
| |
| void BugReport::clearVisitors() { |
| Callbacks.clear(); |
| } |
| |
| BugReport::~BugReport() { |
| while (!interestingSymbols.empty()) { |
| popInterestingSymbolsAndRegions(); |
| } |
| } |
| |
| const Decl *BugReport::getDeclWithIssue() const { |
| if (DeclWithIssue) |
| return DeclWithIssue; |
| |
| const ExplodedNode *N = getErrorNode(); |
| if (!N) |
| return nullptr; |
| |
| const LocationContext *LC = N->getLocationContext(); |
| return LC->getStackFrame()->getDecl(); |
| } |
| |
| void BugReport::Profile(llvm::FoldingSetNodeID& hash) const { |
| hash.AddPointer(&BT); |
| hash.AddString(Description); |
| PathDiagnosticLocation UL = getUniqueingLocation(); |
| if (UL.isValid()) { |
| UL.Profile(hash); |
| } else if (Location.isValid()) { |
| Location.Profile(hash); |
| } else { |
| assert(ErrorNode); |
| hash.AddPointer(GetCurrentOrPreviousStmt(ErrorNode)); |
| } |
| |
| for (SourceRange range : Ranges) { |
| if (!range.isValid()) |
| continue; |
| hash.AddInteger(range.getBegin().getRawEncoding()); |
| hash.AddInteger(range.getEnd().getRawEncoding()); |
| } |
| } |
| |
| void BugReport::markInteresting(SymbolRef sym) { |
| if (!sym) |
| return; |
| |
| getInterestingSymbols().insert(sym); |
| |
| if (const auto *meta = dyn_cast<SymbolMetadata>(sym)) |
| getInterestingRegions().insert(meta->getRegion()); |
| } |
| |
| void BugReport::markInteresting(const MemRegion *R) { |
| if (!R) |
| return; |
| |
| R = R->getBaseRegion(); |
| getInterestingRegions().insert(R); |
| |
| if (const auto *SR = dyn_cast<SymbolicRegion>(R)) |
| getInterestingSymbols().insert(SR->getSymbol()); |
| } |
| |
| void BugReport::markInteresting(SVal V) { |
| markInteresting(V.getAsRegion()); |
| markInteresting(V.getAsSymbol()); |
| } |
| |
| void BugReport::markInteresting(const LocationContext *LC) { |
| if (!LC) |
| return; |
| InterestingLocationContexts.insert(LC); |
| } |
| |
| bool BugReport::isInteresting(SVal V) { |
| return isInteresting(V.getAsRegion()) || isInteresting(V.getAsSymbol()); |
| } |
| |
| bool BugReport::isInteresting(SymbolRef sym) { |
| if (!sym) |
| return false; |
| // We don't currently consider metadata symbols to be interesting |
| // even if we know their region is interesting. Is that correct behavior? |
| return getInterestingSymbols().count(sym); |
| } |
| |
| bool BugReport::isInteresting(const MemRegion *R) { |
| if (!R) |
| return false; |
| R = R->getBaseRegion(); |
| bool b = getInterestingRegions().count(R); |
| if (b) |
| return true; |
| if (const auto *SR = dyn_cast<SymbolicRegion>(R)) |
| return getInterestingSymbols().count(SR->getSymbol()); |
| return false; |
| } |
| |
| bool BugReport::isInteresting(const LocationContext *LC) { |
| if (!LC) |
| return false; |
| return InterestingLocationContexts.count(LC); |
| } |
| |
| void BugReport::lazyInitializeInterestingSets() { |
| if (interestingSymbols.empty()) { |
| interestingSymbols.push_back(new Symbols()); |
| interestingRegions.push_back(new Regions()); |
| } |
| } |
| |
| BugReport::Symbols &BugReport::getInterestingSymbols() { |
| lazyInitializeInterestingSets(); |
| return *interestingSymbols.back(); |
| } |
| |
| BugReport::Regions &BugReport::getInterestingRegions() { |
| lazyInitializeInterestingSets(); |
| return *interestingRegions.back(); |
| } |
| |
| void BugReport::pushInterestingSymbolsAndRegions() { |
| interestingSymbols.push_back(new Symbols(getInterestingSymbols())); |
| interestingRegions.push_back(new Regions(getInterestingRegions())); |
| } |
| |
| void BugReport::popInterestingSymbolsAndRegions() { |
| delete interestingSymbols.pop_back_val(); |
| delete interestingRegions.pop_back_val(); |
| } |
| |
| const Stmt *BugReport::getStmt() const { |
| if (!ErrorNode) |
| return nullptr; |
| |
| ProgramPoint ProgP = ErrorNode->getLocation(); |
| const Stmt *S = nullptr; |
| |
| if (Optional<BlockEntrance> BE = ProgP.getAs<BlockEntrance>()) { |
| CFGBlock &Exit = ProgP.getLocationContext()->getCFG()->getExit(); |
| if (BE->getBlock() == &Exit) |
| S = GetPreviousStmt(ErrorNode); |
| } |
| if (!S) |
| S = PathDiagnosticLocation::getStmt(ErrorNode); |
| |
| return S; |
| } |
| |
| llvm::iterator_range<BugReport::ranges_iterator> BugReport::getRanges() { |
| // If no custom ranges, add the range of the statement corresponding to |
| // the error node. |
| if (Ranges.empty()) { |
| if (const auto *E = dyn_cast_or_null<Expr>(getStmt())) |
| addRange(E->getSourceRange()); |
| else |
| return llvm::make_range(ranges_iterator(), ranges_iterator()); |
| } |
| |
| // User-specified absence of range info. |
| if (Ranges.size() == 1 && !Ranges.begin()->isValid()) |
| return llvm::make_range(ranges_iterator(), ranges_iterator()); |
| |
| return llvm::make_range(Ranges.begin(), Ranges.end()); |
| } |
| |
| PathDiagnosticLocation BugReport::getLocation(const SourceManager &SM) const { |
| if (ErrorNode) { |
| assert(!Location.isValid() && |
| "Either Location or ErrorNode should be specified but not both."); |
| return PathDiagnosticLocation::createEndOfPath(ErrorNode, SM); |
| } |
| |
| assert(Location.isValid()); |
| return Location; |
| } |
| |
| //===----------------------------------------------------------------------===// |
| // Methods for BugReporter and subclasses. |
| //===----------------------------------------------------------------------===// |
| |
| BugReportEquivClass::~BugReportEquivClass() = default; |
| |
| GRBugReporter::~GRBugReporter() = default; |
| |
| BugReporterData::~BugReporterData() = default; |
| |
| ExplodedGraph &GRBugReporter::getGraph() { return Eng.getGraph(); } |
| |
| ProgramStateManager& |
| GRBugReporter::getStateManager() { return Eng.getStateManager(); } |
| |
| BugReporter::~BugReporter() { |
| FlushReports(); |
| |
| // Free the bug reports we are tracking. |
| for (const auto I : EQClassesVector) |
| delete I; |
| } |
| |
| void BugReporter::FlushReports() { |
| if (BugTypes.isEmpty()) |
| return; |
| |
| // First flush the warnings for each BugType. This may end up creating new |
| // warnings and new BugTypes. |
| // FIXME: Only NSErrorChecker needs BugType's FlushReports. |
| // Turn NSErrorChecker into a proper checker and remove this. |
| SmallVector<const BugType *, 16> bugTypes(BugTypes.begin(), BugTypes.end()); |
| for (const auto I : bugTypes) |
| const_cast<BugType*>(I)->FlushReports(*this); |
| |
| // We need to flush reports in deterministic order to ensure the order |
| // of the reports is consistent between runs. |
| for (const auto EQ : EQClassesVector) |
| FlushReport(*EQ); |
| |
| // BugReporter owns and deletes only BugTypes created implicitly through |
| // EmitBasicReport. |
| // FIXME: There are leaks from checkers that assume that the BugTypes they |
| // create will be destroyed by the BugReporter. |
| llvm::DeleteContainerSeconds(StrBugTypes); |
| |
| // Remove all references to the BugType objects. |
| BugTypes = F.getEmptySet(); |
| } |
| |
| //===----------------------------------------------------------------------===// |
| // PathDiagnostics generation. |
| //===----------------------------------------------------------------------===// |
| |
| namespace { |
| |
| /// A wrapper around a report graph, which contains only a single path, and its |
| /// node maps. |
| class ReportGraph { |
| public: |
| InterExplodedGraphMap BackMap; |
| std::unique_ptr<ExplodedGraph> Graph; |
| const ExplodedNode *ErrorNode; |
| size_t Index; |
| }; |
| |
| /// A wrapper around a trimmed graph and its node maps. |
| class TrimmedGraph { |
| InterExplodedGraphMap InverseMap; |
| |
| using PriorityMapTy = llvm::DenseMap<const ExplodedNode *, unsigned>; |
| |
| PriorityMapTy PriorityMap; |
| |
| using NodeIndexPair = std::pair<const ExplodedNode *, size_t>; |
| |
| SmallVector<NodeIndexPair, 32> ReportNodes; |
| |
| std::unique_ptr<ExplodedGraph> G; |
| |
| /// A helper class for sorting ExplodedNodes by priority. |
| template <bool Descending> |
| class PriorityCompare { |
| const PriorityMapTy &PriorityMap; |
| |
| public: |
| PriorityCompare(const PriorityMapTy &M) : PriorityMap(M) {} |
| |
| bool operator()(const ExplodedNode *LHS, const ExplodedNode *RHS) const { |
| PriorityMapTy::const_iterator LI = PriorityMap.find(LHS); |
| PriorityMapTy::const_iterator RI = PriorityMap.find(RHS); |
| PriorityMapTy::const_iterator E = PriorityMap.end(); |
| |
| if (LI == E) |
| return Descending; |
| if (RI == E) |
| return !Descending; |
| |
| return Descending ? LI->second > RI->second |
| : LI->second < RI->second; |
| } |
| |
| bool operator()(const NodeIndexPair &LHS, const NodeIndexPair &RHS) const { |
| return (*this)(LHS.first, RHS.first); |
| } |
| }; |
| |
| public: |
| TrimmedGraph(const ExplodedGraph *OriginalGraph, |
| ArrayRef<const ExplodedNode *> Nodes); |
| |
| bool popNextReportGraph(ReportGraph &GraphWrapper); |
| }; |
| |
| } // namespace |
| |
| TrimmedGraph::TrimmedGraph(const ExplodedGraph *OriginalGraph, |
| ArrayRef<const ExplodedNode *> Nodes) { |
| // The trimmed graph is created in the body of the constructor to ensure |
| // that the DenseMaps have been initialized already. |
| InterExplodedGraphMap ForwardMap; |
| G = OriginalGraph->trim(Nodes, &ForwardMap, &InverseMap); |
| |
| // Find the (first) error node in the trimmed graph. We just need to consult |
| // the node map which maps from nodes in the original graph to nodes |
| // in the new graph. |
| llvm::SmallPtrSet<const ExplodedNode *, 32> RemainingNodes; |
| |
| for (unsigned i = 0, count = Nodes.size(); i < count; ++i) { |
| if (const ExplodedNode *NewNode = ForwardMap.lookup(Nodes[i])) { |
| ReportNodes.push_back(std::make_pair(NewNode, i)); |
| RemainingNodes.insert(NewNode); |
| } |
| } |
| |
| assert(!RemainingNodes.empty() && "No error node found in the trimmed graph"); |
| |
| // Perform a forward BFS to find all the shortest paths. |
| std::queue<const ExplodedNode *> WS; |
| |
| assert(G->num_roots() == 1); |
| WS.push(*G->roots_begin()); |
| unsigned Priority = 0; |
| |
| while (!WS.empty()) { |
| const ExplodedNode *Node = WS.front(); |
| WS.pop(); |
| |
| PriorityMapTy::iterator PriorityEntry; |
| bool IsNew; |
| std::tie(PriorityEntry, IsNew) = |
| PriorityMap.insert(std::make_pair(Node, Priority)); |
| ++Priority; |
| |
| if (!IsNew) { |
| assert(PriorityEntry->second <= Priority); |
| continue; |
| } |
| |
| if (RemainingNodes.erase(Node)) |
| if (RemainingNodes.empty()) |
| break; |
| |
| for (ExplodedNode::const_pred_iterator I = Node->succ_begin(), |
| E = Node->succ_end(); |
| I != E; ++I) |
| WS.push(*I); |
| } |
| |
| // Sort the error paths from longest to shortest. |
| llvm::sort(ReportNodes.begin(), ReportNodes.end(), |
| PriorityCompare<true>(PriorityMap)); |
| } |
| |
| bool TrimmedGraph::popNextReportGraph(ReportGraph &GraphWrapper) { |
| if (ReportNodes.empty()) |
| return false; |
| |
| const ExplodedNode *OrigN; |
| std::tie(OrigN, GraphWrapper.Index) = ReportNodes.pop_back_val(); |
| assert(PriorityMap.find(OrigN) != PriorityMap.end() && |
| "error node not accessible from root"); |
| |
| // Create a new graph with a single path. This is the graph |
| // that will be returned to the caller. |
| auto GNew = llvm::make_unique<ExplodedGraph>(); |
| GraphWrapper.BackMap.clear(); |
| |
| // Now walk from the error node up the BFS path, always taking the |
| // predeccessor with the lowest number. |
| ExplodedNode *Succ = nullptr; |
| while (true) { |
| // Create the equivalent node in the new graph with the same state |
| // and location. |
| ExplodedNode *NewN = GNew->createUncachedNode(OrigN->getLocation(), OrigN->getState(), |
| OrigN->isSink()); |
| |
| // Store the mapping to the original node. |
| InterExplodedGraphMap::const_iterator IMitr = InverseMap.find(OrigN); |
| assert(IMitr != InverseMap.end() && "No mapping to original node."); |
| GraphWrapper.BackMap[NewN] = IMitr->second; |
| |
| // Link up the new node with the previous node. |
| if (Succ) |
| Succ->addPredecessor(NewN, *GNew); |
| else |
| GraphWrapper.ErrorNode = NewN; |
| |
| Succ = NewN; |
| |
| // Are we at the final node? |
| if (OrigN->pred_empty()) { |
| GNew->addRoot(NewN); |
| break; |
| } |
| |
| // Find the next predeccessor node. We choose the node that is marked |
| // with the lowest BFS number. |
| OrigN = *std::min_element(OrigN->pred_begin(), OrigN->pred_end(), |
| PriorityCompare<false>(PriorityMap)); |
| } |
| |
| GraphWrapper.Graph = std::move(GNew); |
| |
| return true; |
| } |
| |
| /// CompactPathDiagnostic - This function postprocesses a PathDiagnostic object |
| /// and collapses PathDiagosticPieces that are expanded by macros. |
| static void CompactPathDiagnostic(PathPieces &path, const SourceManager& SM) { |
| using MacroStackTy = |
| std::vector< |
| std::pair<std::shared_ptr<PathDiagnosticMacroPiece>, SourceLocation>>; |
| |
| using PiecesTy = std::vector<std::shared_ptr<PathDiagnosticPiece>>; |
| |
| MacroStackTy MacroStack; |
| PiecesTy Pieces; |
| |
| for (PathPieces::const_iterator I = path.begin(), E = path.end(); |
| I != E; ++I) { |
| const auto &piece = *I; |
| |
| // Recursively compact calls. |
| if (auto *call = dyn_cast<PathDiagnosticCallPiece>(&*piece)) { |
| CompactPathDiagnostic(call->path, SM); |
| } |
| |
| // Get the location of the PathDiagnosticPiece. |
| const FullSourceLoc Loc = piece->getLocation().asLocation(); |
| |
| // Determine the instantiation location, which is the location we group |
| // related PathDiagnosticPieces. |
| SourceLocation InstantiationLoc = Loc.isMacroID() ? |
| SM.getExpansionLoc(Loc) : |
| SourceLocation(); |
| |
| if (Loc.isFileID()) { |
| MacroStack.clear(); |
| Pieces.push_back(piece); |
| continue; |
| } |
| |
| assert(Loc.isMacroID()); |
| |
| // Is the PathDiagnosticPiece within the same macro group? |
| if (!MacroStack.empty() && InstantiationLoc == MacroStack.back().second) { |
| MacroStack.back().first->subPieces.push_back(piece); |
| continue; |
| } |
| |
| // We aren't in the same group. Are we descending into a new macro |
| // or are part of an old one? |
| std::shared_ptr<PathDiagnosticMacroPiece> MacroGroup; |
| |
| SourceLocation ParentInstantiationLoc = InstantiationLoc.isMacroID() ? |
| SM.getExpansionLoc(Loc) : |
| SourceLocation(); |
| |
| // Walk the entire macro stack. |
| while (!MacroStack.empty()) { |
| if (InstantiationLoc == MacroStack.back().second) { |
| MacroGroup = MacroStack.back().first; |
| break; |
| } |
| |
| if (ParentInstantiationLoc == MacroStack.back().second) { |
| MacroGroup = MacroStack.back().first; |
| break; |
| } |
| |
| MacroStack.pop_back(); |
| } |
| |
| if (!MacroGroup || ParentInstantiationLoc == MacroStack.back().second) { |
| // Create a new macro group and add it to the stack. |
| auto NewGroup = std::make_shared<PathDiagnosticMacroPiece>( |
| PathDiagnosticLocation::createSingleLocation(piece->getLocation())); |
| |
| if (MacroGroup) |
| MacroGroup->subPieces.push_back(NewGroup); |
| else { |
| assert(InstantiationLoc.isFileID()); |
| Pieces.push_back(NewGroup); |
| } |
| |
| MacroGroup = NewGroup; |
| MacroStack.push_back(std::make_pair(MacroGroup, InstantiationLoc)); |
| } |
| |
| // Finally, add the PathDiagnosticPiece to the group. |
| MacroGroup->subPieces.push_back(piece); |
| } |
| |
| // Now take the pieces and construct a new PathDiagnostic. |
| path.clear(); |
| |
| path.insert(path.end(), Pieces.begin(), Pieces.end()); |
| } |
| |
| /// Generate notes from all visitors. |
| /// Notes associated with {@code ErrorNode} are generated using |
| /// {@code getEndPath}, and the rest are generated with {@code VisitNode}. |
| static std::unique_ptr<VisitorsDiagnosticsTy> |
| generateVisitorsDiagnostics(BugReport *R, const ExplodedNode *ErrorNode, |
| BugReporterContext &BRC) { |
| auto Notes = llvm::make_unique<VisitorsDiagnosticsTy>(); |
| BugReport::VisitorList visitors; |
| |
| // Run visitors on all nodes starting from the node *before* the last one. |
| // The last node is reserved for notes generated with {@code getEndPath}. |
| const ExplodedNode *NextNode = ErrorNode->getFirstPred(); |
| while (NextNode) { |
| |
| // At each iteration, move all visitors from report to visitor list. |
| for (BugReport::visitor_iterator I = R->visitor_begin(), |
| E = R->visitor_end(); |
| I != E; ++I) { |
| visitors.push_back(std::move(*I)); |
| } |
| R->clearVisitors(); |
| |
| const ExplodedNode *Pred = NextNode->getFirstPred(); |
| if (!Pred) { |
| std::shared_ptr<PathDiagnosticPiece> LastPiece; |
| for (auto &V : visitors) { |
| V->finalizeVisitor(BRC, ErrorNode, *R); |
| |
| if (auto Piece = V->getEndPath(BRC, ErrorNode, *R)) { |
| assert(!LastPiece && |
| "There can only be one final piece in a diagnostic."); |
| LastPiece = std::move(Piece); |
| (*Notes)[ErrorNode].push_back(LastPiece); |
| } |
| } |
| break; |
| } |
| |
| for (auto &V : visitors) { |
| auto P = V->VisitNode(NextNode, Pred, BRC, *R); |
| if (P) |
| (*Notes)[NextNode].push_back(std::move(P)); |
| } |
| |
| if (!R->isValid()) |
| break; |
| |
| NextNode = Pred; |
| } |
| |
| return Notes; |
| } |
| |
| /// Find a non-invalidated report for a given equivalence class, |
| /// and return together with a cache of visitors notes. |
| /// If none found, return a nullptr paired with an empty cache. |
| static |
| std::pair<BugReport*, std::unique_ptr<VisitorsDiagnosticsTy>> findValidReport( |
| TrimmedGraph &TrimG, |
| ReportGraph &ErrorGraph, |
| ArrayRef<BugReport *> &bugReports, |
| AnalyzerOptions &Opts, |
| GRBugReporter &Reporter) { |
| |
| while (TrimG.popNextReportGraph(ErrorGraph)) { |
| // Find the BugReport with the original location. |
| assert(ErrorGraph.Index < bugReports.size()); |
| BugReport *R = bugReports[ErrorGraph.Index]; |
| assert(R && "No original report found for sliced graph."); |
| assert(R->isValid() && "Report selected by trimmed graph marked invalid."); |
| const ExplodedNode *ErrorNode = ErrorGraph.ErrorNode; |
| |
| // Register refutation visitors first, if they mark the bug invalid no |
| // further analysis is required |
| R->addVisitor(llvm::make_unique<LikelyFalsePositiveSuppressionBRVisitor>()); |
| |
| // Register additional node visitors. |
| R->addVisitor(llvm::make_unique<NilReceiverBRVisitor>()); |
| R->addVisitor(llvm::make_unique<ConditionBRVisitor>()); |
| R->addVisitor(llvm::make_unique<CXXSelfAssignmentBRVisitor>()); |
| |
| BugReporterContext BRC(Reporter, ErrorGraph.BackMap); |
| |
| // Run all visitors on a given graph, once. |
| std::unique_ptr<VisitorsDiagnosticsTy> visitorNotes = |
| generateVisitorsDiagnostics(R, ErrorNode, BRC); |
| |
| if (R->isValid()) { |
| if (Opts.shouldCrosscheckWithZ3()) { |
| // If crosscheck is enabled, remove all visitors, add the refutation |
| // visitor and check again |
| R->clearVisitors(); |
| R->addVisitor(llvm::make_unique<FalsePositiveRefutationBRVisitor>()); |
| |
| // We don't overrite the notes inserted by other visitors because the |
| // refutation manager does not add any new note to the path |
| generateVisitorsDiagnostics(R, ErrorGraph.ErrorNode, BRC); |
| } |
| |
| // Check if the bug is still valid |
| if (R->isValid()) |
| return std::make_pair(R, std::move(visitorNotes)); |
| } |
| } |
| |
| return std::make_pair(nullptr, llvm::make_unique<VisitorsDiagnosticsTy>()); |
| } |
| |
| std::unique_ptr<DiagnosticForConsumerMapTy> |
| GRBugReporter::generatePathDiagnostics( |
| ArrayRef<PathDiagnosticConsumer *> consumers, |
| ArrayRef<BugReport *> &bugReports) { |
| assert(!bugReports.empty()); |
| |
| auto Out = llvm::make_unique<DiagnosticForConsumerMapTy>(); |
| bool HasValid = false; |
| SmallVector<const ExplodedNode *, 32> errorNodes; |
| for (const auto I : bugReports) { |
| if (I->isValid()) { |
| HasValid = true; |
| errorNodes.push_back(I->getErrorNode()); |
| } else { |
| // Keep the errorNodes list in sync with the bugReports list. |
| errorNodes.push_back(nullptr); |
| } |
| } |
| |
| // If all the reports have been marked invalid by a previous path generation, |
| // we're done. |
| if (!HasValid) |
| return Out; |
| |
| TrimmedGraph TrimG(&getGraph(), errorNodes); |
| ReportGraph ErrorGraph; |
| auto ReportInfo = findValidReport(TrimG, ErrorGraph, bugReports, |
| getAnalyzerOptions(), *this); |
| BugReport *R = ReportInfo.first; |
| |
| if (R && R->isValid()) { |
| const ExplodedNode *ErrorNode = ErrorGraph.ErrorNode; |
| for (PathDiagnosticConsumer *PC : consumers) { |
| PathDiagnosticBuilder PDB(*this, R, ErrorGraph.BackMap, PC); |
| std::unique_ptr<PathDiagnostic> PD = generatePathDiagnosticForConsumer( |
| PC->getGenerationScheme(), PDB, ErrorNode, *ReportInfo.second); |
| (*Out)[PC] = std::move(PD); |
| } |
| } |
| |
| return Out; |
| } |
| |
| void BugReporter::Register(BugType *BT) { |
| BugTypes = F.add(BugTypes, BT); |
| } |
| |
| void BugReporter::emitReport(std::unique_ptr<BugReport> R) { |
| if (const ExplodedNode *E = R->getErrorNode()) { |
| // An error node must either be a sink or have a tag, otherwise |
| // it could get reclaimed before the path diagnostic is created. |
| assert((E->isSink() || E->getLocation().getTag()) && |
| "Error node must either be a sink or have a tag"); |
| |
| const AnalysisDeclContext *DeclCtx = |
| E->getLocationContext()->getAnalysisDeclContext(); |
| // The source of autosynthesized body can be handcrafted AST or a model |
| // file. The locations from handcrafted ASTs have no valid source locations |
| // and have to be discarded. Locations from model files should be preserved |
| // for processing and reporting. |
| if (DeclCtx->isBodyAutosynthesized() && |
| !DeclCtx->isBodyAutosynthesizedFromModelFile()) |
| return; |
| } |
| |
| bool ValidSourceLoc = R->getLocation(getSourceManager()).isValid(); |
| assert(ValidSourceLoc); |
| // If we mess up in a release build, we'd still prefer to just drop the bug |
| // instead of trying to go on. |
| if (!ValidSourceLoc) |
| return; |
| |
| // Compute the bug report's hash to determine its equivalence class. |
| llvm::FoldingSetNodeID ID; |
| R->Profile(ID); |
| |
| // Lookup the equivance class. If there isn't one, create it. |
| BugType& BT = R->getBugType(); |
| Register(&BT); |
| void *InsertPos; |
| BugReportEquivClass* EQ = EQClasses.FindNodeOrInsertPos(ID, InsertPos); |
| |
| if (!EQ) { |
| EQ = new BugReportEquivClass(std::move(R)); |
| EQClasses.InsertNode(EQ, InsertPos); |
| EQClassesVector.push_back(EQ); |
| } else |
| EQ->AddReport(std::move(R)); |
| } |
| |
| //===----------------------------------------------------------------------===// |
| // Emitting reports in equivalence classes. |
| //===----------------------------------------------------------------------===// |
| |
| namespace { |
| |
| struct FRIEC_WLItem { |
| const ExplodedNode *N; |
| ExplodedNode::const_succ_iterator I, E; |
| |
| FRIEC_WLItem(const ExplodedNode *n) |
| : N(n), I(N->succ_begin()), E(N->succ_end()) {} |
| }; |
| |
| } // namespace |
| |
| static const CFGBlock *findBlockForNode(const ExplodedNode *N) { |
| ProgramPoint P = N->getLocation(); |
| if (auto BEP = P.getAs<BlockEntrance>()) |
| return BEP->getBlock(); |
| |
| // Find the node's current statement in the CFG. |
| if (const Stmt *S = PathDiagnosticLocation::getStmt(N)) |
| return N->getLocationContext()->getAnalysisDeclContext() |
| ->getCFGStmtMap()->getBlock(S); |
| |
| return nullptr; |
| } |
| |
| // Returns true if by simply looking at the block, we can be sure that it |
| // results in a sink during analysis. This is useful to know when the analysis |
| // was interrupted, and we try to figure out if it would sink eventually. |
| // There may be many more reasons why a sink would appear during analysis |
| // (eg. checkers may generate sinks arbitrarily), but here we only consider |
| // sinks that would be obvious by looking at the CFG. |
| static bool isImmediateSinkBlock(const CFGBlock *Blk) { |
| if (Blk->hasNoReturnElement()) |
| return true; |
| |
| // FIXME: Throw-expressions are currently generating sinks during analysis: |
| // they're not supported yet, and also often used for actually terminating |
| // the program. So we should treat them as sinks in this analysis as well, |
| // at least for now, but once we have better support for exceptions, |
| // we'd need to carefully handle the case when the throw is being |
| // immediately caught. |
| if (std::any_of(Blk->begin(), Blk->end(), [](const CFGElement &Elm) { |
| if (Optional<CFGStmt> StmtElm = Elm.getAs<CFGStmt>()) |
| if (isa<CXXThrowExpr>(StmtElm->getStmt())) |
| return true; |
| return false; |
| })) |
| return true; |
| |
| return false; |
| } |
| |
| // Returns true if by looking at the CFG surrounding the node's program |
| // point, we can be sure that any analysis starting from this point would |
| // eventually end with a sink. We scan the child CFG blocks in a depth-first |
| // manner and see if all paths eventually end up in an immediate sink block. |
| static bool isInevitablySinking(const ExplodedNode *N) { |
| const CFG &Cfg = N->getCFG(); |
| |
| const CFGBlock *StartBlk = findBlockForNode(N); |
| if (!StartBlk) |
| return false; |
| if (isImmediateSinkBlock(StartBlk)) |
| return true; |
| |
| llvm::SmallVector<const CFGBlock *, 32> DFSWorkList; |
| llvm::SmallPtrSet<const CFGBlock *, 32> Visited; |
| |
| DFSWorkList.push_back(StartBlk); |
| while (!DFSWorkList.empty()) { |
| const CFGBlock *Blk = DFSWorkList.back(); |
| DFSWorkList.pop_back(); |
| Visited.insert(Blk); |
| |
| for (const auto &Succ : Blk->succs()) { |
| if (const CFGBlock *SuccBlk = Succ.getReachableBlock()) { |
| if (SuccBlk == &Cfg.getExit()) { |
| // If at least one path reaches the CFG exit, it means that control is |
| // returned to the caller. For now, say that we are not sure what |
| // happens next. If necessary, this can be improved to analyze |
| // the parent StackFrameContext's call site in a similar manner. |
| return false; |
| } |
| |
| if (!isImmediateSinkBlock(SuccBlk) && !Visited.count(SuccBlk)) { |
| // If the block has reachable child blocks that aren't no-return, |
| // add them to the worklist. |
| DFSWorkList.push_back(SuccBlk); |
| } |
| } |
| } |
| } |
| |
| // Nothing reached the exit. It can only mean one thing: there's no return. |
| return true; |
| } |
| |
| static BugReport * |
| FindReportInEquivalenceClass(BugReportEquivClass& EQ, |
| SmallVectorImpl<BugReport*> &bugReports) { |
| BugReportEquivClass::iterator I = EQ.begin(), E = EQ.end(); |
| assert(I != E); |
| BugType& BT = I->getBugType(); |
| |
| // If we don't need to suppress any of the nodes because they are |
| // post-dominated by a sink, simply add all the nodes in the equivalence class |
| // to 'Nodes'. Any of the reports will serve as a "representative" report. |
| if (!BT.isSuppressOnSink()) { |
| BugReport *R = &*I; |
| for (auto &I : EQ) { |
| const ExplodedNode *N = I.getErrorNode(); |
| if (N) { |
| R = &I; |
| bugReports.push_back(R); |
| } |
| } |
| return R; |
| } |
| |
| // For bug reports that should be suppressed when all paths are post-dominated |
| // by a sink node, iterate through the reports in the equivalence class |
| // until we find one that isn't post-dominated (if one exists). We use a |
| // DFS traversal of the ExplodedGraph to find a non-sink node. We could write |
| // this as a recursive function, but we don't want to risk blowing out the |
| // stack for very long paths. |
| BugReport *exampleReport = nullptr; |
| |
| for (; I != E; ++I) { |
| const ExplodedNode *errorNode = I->getErrorNode(); |
| |
| if (!errorNode) |
| continue; |
| if (errorNode->isSink()) { |
| llvm_unreachable( |
| "BugType::isSuppressSink() should not be 'true' for sink end nodes"); |
| } |
| // No successors? By definition this nodes isn't post-dominated by a sink. |
| if (errorNode->succ_empty()) { |
| bugReports.push_back(&*I); |
| if (!exampleReport) |
| exampleReport = &*I; |
| continue; |
| } |
| |
| // See if we are in a no-return CFG block. If so, treat this similarly |
| // to being post-dominated by a sink. This works better when the analysis |
| // is incomplete and we have never reached the no-return function call(s) |
| // that we'd inevitably bump into on this path. |
| if (isInevitablySinking(errorNode)) |
| continue; |
| |
| // At this point we know that 'N' is not a sink and it has at least one |
| // successor. Use a DFS worklist to find a non-sink end-of-path node. |
| using WLItem = FRIEC_WLItem; |
| using DFSWorkList = SmallVector<WLItem, 10>; |
| |
| llvm::DenseMap<const ExplodedNode *, unsigned> Visited; |
| |
| DFSWorkList WL; |
| WL.push_back(errorNode); |
| Visited[errorNode] = 1; |
| |
| while (!WL.empty()) { |
| WLItem &WI = WL.back(); |
| assert(!WI.N->succ_empty()); |
| |
| for (; WI.I != WI.E; ++WI.I) { |
| const ExplodedNode *Succ = *WI.I; |
| // End-of-path node? |
| if (Succ->succ_empty()) { |
| // If we found an end-of-path node that is not a sink. |
| if (!Succ->isSink()) { |
| bugReports.push_back(&*I); |
| if (!exampleReport) |
| exampleReport = &*I; |
| WL.clear(); |
| break; |
| } |
| // Found a sink? Continue on to the next successor. |
| continue; |
| } |
| // Mark the successor as visited. If it hasn't been explored, |
| // enqueue it to the DFS worklist. |
| unsigned &mark = Visited[Succ]; |
| if (!mark) { |
| mark = 1; |
| WL.push_back(Succ); |
| break; |
| } |
| } |
| |
| // The worklist may have been cleared at this point. First |
| // check if it is empty before checking the last item. |
| if (!WL.empty() && &WL.back() == &WI) |
| WL.pop_back(); |
| } |
| } |
| |
| // ExampleReport will be NULL if all the nodes in the equivalence class |
| // were post-dominated by sinks. |
| return exampleReport; |
| } |
| |
| void BugReporter::FlushReport(BugReportEquivClass& EQ) { |
| SmallVector<BugReport*, 10> bugReports; |
| BugReport *report = FindReportInEquivalenceClass(EQ, bugReports); |
| if (!report) |
| return; |
| |
| ArrayRef<PathDiagnosticConsumer*> Consumers = getPathDiagnosticConsumers(); |
| std::unique_ptr<DiagnosticForConsumerMapTy> Diagnostics = |
| generateDiagnosticForConsumerMap(report, Consumers, bugReports); |
| |
| for (auto &P : *Diagnostics) { |
| PathDiagnosticConsumer *Consumer = P.first; |
| std::unique_ptr<PathDiagnostic> &PD = P.second; |
| |
| // If the path is empty, generate a single step path with the location |
| // of the issue. |
| if (PD->path.empty()) { |
| PathDiagnosticLocation L = report->getLocation(getSourceManager()); |
| auto piece = llvm::make_unique<PathDiagnosticEventPiece>( |
| L, report->getDescription()); |
| for (SourceRange Range : report->getRanges()) |
| piece->addRange(Range); |
| PD->setEndOfPath(std::move(piece)); |
| } |
| |
| PathPieces &Pieces = PD->getMutablePieces(); |
| if (getAnalyzerOptions().shouldDisplayNotesAsEvents()) { |
| // For path diagnostic consumers that don't support extra notes, |
| // we may optionally convert those to path notes. |
| for (auto I = report->getNotes().rbegin(), |
| E = report->getNotes().rend(); I != E; ++I) { |
| PathDiagnosticNotePiece *Piece = I->get(); |
| auto ConvertedPiece = std::make_shared<PathDiagnosticEventPiece>( |
| Piece->getLocation(), Piece->getString()); |
| for (const auto &R: Piece->getRanges()) |
| ConvertedPiece->addRange(R); |
| |
| Pieces.push_front(std::move(ConvertedPiece)); |
| } |
| } else { |
| for (auto I = report->getNotes().rbegin(), |
| E = report->getNotes().rend(); I != E; ++I) |
| Pieces.push_front(*I); |
| } |
| |
| // Get the meta data. |
| const BugReport::ExtraTextList &Meta = report->getExtraText(); |
| for (const auto &i : Meta) |
| PD->addMeta(i); |
| |
| Consumer->HandlePathDiagnostic(std::move(PD)); |
| } |
| } |
| |
| /// Insert all lines participating in the function signature \p Signature |
| /// into \p ExecutedLines. |
| static void populateExecutedLinesWithFunctionSignature( |
| const Decl *Signature, SourceManager &SM, |
| std::unique_ptr<FilesToLineNumsMap> &ExecutedLines) { |
| SourceRange SignatureSourceRange; |
| const Stmt* Body = Signature->getBody(); |
| if (const auto FD = dyn_cast<FunctionDecl>(Signature)) { |
| SignatureSourceRange = FD->getSourceRange(); |
| } else if (const auto OD = dyn_cast<ObjCMethodDecl>(Signature)) { |
| SignatureSourceRange = OD->getSourceRange(); |
| } else { |
| return; |
| } |
| SourceLocation Start = SignatureSourceRange.getBegin(); |
| SourceLocation End = Body ? Body->getSourceRange().getBegin() |
| : SignatureSourceRange.getEnd(); |
| unsigned StartLine = SM.getExpansionLineNumber(Start); |
| unsigned EndLine = SM.getExpansionLineNumber(End); |
| |
| FileID FID = SM.getFileID(SM.getExpansionLoc(Start)); |
| for (unsigned Line = StartLine; Line <= EndLine; Line++) |
| ExecutedLines->operator[](FID.getHashValue()).insert(Line); |
| } |
| |
| static void populateExecutedLinesWithStmt( |
| const Stmt *S, SourceManager &SM, |
| std::unique_ptr<FilesToLineNumsMap> &ExecutedLines) { |
| SourceLocation Loc = S->getSourceRange().getBegin(); |
| SourceLocation ExpansionLoc = SM.getExpansionLoc(Loc); |
| FileID FID = SM.getFileID(ExpansionLoc); |
| unsigned LineNo = SM.getExpansionLineNumber(ExpansionLoc); |
| ExecutedLines->operator[](FID.getHashValue()).insert(LineNo); |
| } |
| |
| /// \return all executed lines including function signatures on the path |
| /// starting from \p N. |
| static std::unique_ptr<FilesToLineNumsMap> |
| findExecutedLines(SourceManager &SM, const ExplodedNode *N) { |
| auto ExecutedLines = llvm::make_unique<FilesToLineNumsMap>(); |
| |
| while (N) { |
| if (N->getFirstPred() == nullptr) { |
| // First node: show signature of the entrance point. |
| const Decl *D = N->getLocationContext()->getDecl(); |
| populateExecutedLinesWithFunctionSignature(D, SM, ExecutedLines); |
| } else if (auto CE = N->getLocationAs<CallEnter>()) { |
| // Inlined function: show signature. |
| const Decl* D = CE->getCalleeContext()->getDecl(); |
| populateExecutedLinesWithFunctionSignature(D, SM, ExecutedLines); |
| } else if (const Stmt *S = PathDiagnosticLocation::getStmt(N)) { |
| populateExecutedLinesWithStmt(S, SM, ExecutedLines); |
| |
| // Show extra context for some parent kinds. |
| const Stmt *P = N->getParentMap().getParent(S); |
| |
| // The path exploration can die before the node with the associated |
| // return statement is generated, but we do want to show the whole |
| // return. |
| if (const auto *RS = dyn_cast_or_null<ReturnStmt>(P)) { |
| populateExecutedLinesWithStmt(RS, SM, ExecutedLines); |
| P = N->getParentMap().getParent(RS); |
| } |
| |
| if (P && (isa<SwitchCase>(P) || isa<LabelStmt>(P))) |
| populateExecutedLinesWithStmt(P, SM, ExecutedLines); |
| } |
| |
| N = N->getFirstPred(); |
| } |
| return ExecutedLines; |
| } |
| |
| std::unique_ptr<DiagnosticForConsumerMapTy> |
| BugReporter::generateDiagnosticForConsumerMap( |
| BugReport *report, ArrayRef<PathDiagnosticConsumer *> consumers, |
| ArrayRef<BugReport *> bugReports) { |
| |
| if (!report->isPathSensitive()) { |
| auto Out = llvm::make_unique<DiagnosticForConsumerMapTy>(); |
| for (auto *Consumer : consumers) |
| (*Out)[Consumer] = generateEmptyDiagnosticForReport(report, |
| getSourceManager()); |
| return Out; |
| } |
| |
| // Generate the full path sensitive diagnostic, using the generation scheme |
| // specified by the PathDiagnosticConsumer. Note that we have to generate |
| // path diagnostics even for consumers which do not support paths, because |
| // the BugReporterVisitors may mark this bug as a false positive. |
| assert(!bugReports.empty()); |
| MaxBugClassSize.updateMax(bugReports.size()); |
| std::unique_ptr<DiagnosticForConsumerMapTy> Out = |
| generatePathDiagnostics(consumers, bugReports); |
| |
| if (Out->empty()) |
| return Out; |
| |
| MaxValidBugClassSize.updateMax(bugReports.size()); |
| |
| // Examine the report and see if the last piece is in a header. Reset the |
| // report location to the last piece in the main source file. |
| AnalyzerOptions &Opts = getAnalyzerOptions(); |
| for (auto const &P : *Out) |
| if (Opts.shouldReportIssuesInMainSourceFile() && !Opts.AnalyzeAll) |
| P.second->resetDiagnosticLocationToMainFile(); |
| |
| return Out; |
| } |
| |
| void BugReporter::EmitBasicReport(const Decl *DeclWithIssue, |
| const CheckerBase *Checker, |
| StringRef Name, StringRef Category, |
| StringRef Str, PathDiagnosticLocation Loc, |
| ArrayRef<SourceRange> Ranges) { |
| EmitBasicReport(DeclWithIssue, Checker->getCheckName(), Name, Category, Str, |
| Loc, Ranges); |
| } |
| |
| void BugReporter::EmitBasicReport(const Decl *DeclWithIssue, |
| CheckName CheckName, |
| StringRef name, StringRef category, |
| StringRef str, PathDiagnosticLocation Loc, |
| ArrayRef<SourceRange> Ranges) { |
| // 'BT' is owned by BugReporter. |
| BugType *BT = getBugTypeForName(CheckName, name, category); |
| auto R = llvm::make_unique<BugReport>(*BT, str, Loc); |
| R->setDeclWithIssue(DeclWithIssue); |
| for (ArrayRef<SourceRange>::iterator I = Ranges.begin(), E = Ranges.end(); |
| I != E; ++I) |
| R->addRange(*I); |
| emitReport(std::move(R)); |
| } |
| |
| BugType *BugReporter::getBugTypeForName(CheckName CheckName, StringRef name, |
| StringRef category) { |
| SmallString<136> fullDesc; |
| llvm::raw_svector_ostream(fullDesc) << CheckName.getName() << ":" << name |
| << ":" << category; |
| BugType *&BT = StrBugTypes[fullDesc]; |
| if (!BT) |
| BT = new BugType(CheckName, name, category); |
| return BT; |
| } |