Revert "[memprof] Update YAML traits for writer purposes (#118720)"
[llvm-project.git] / clang / lib / StaticAnalyzer / Core / BugReporter.cpp
blob2904eab0097dc8a7054fa3c0929e1f1c5f56b7f0
1 //===- BugReporter.cpp - Generate PathDiagnostics for bugs ----------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This file defines BugReporter, a utility class for generating
10 // PathDiagnostics.
12 //===----------------------------------------------------------------------===//
14 #include "clang/StaticAnalyzer/Core/BugReporter/BugReporter.h"
15 #include "clang/AST/ASTTypeTraits.h"
16 #include "clang/AST/Attr.h"
17 #include "clang/AST/Decl.h"
18 #include "clang/AST/DeclBase.h"
19 #include "clang/AST/DeclObjC.h"
20 #include "clang/AST/Expr.h"
21 #include "clang/AST/ExprCXX.h"
22 #include "clang/AST/ParentMap.h"
23 #include "clang/AST/ParentMapContext.h"
24 #include "clang/AST/Stmt.h"
25 #include "clang/AST/StmtCXX.h"
26 #include "clang/AST/StmtObjC.h"
27 #include "clang/Analysis/AnalysisDeclContext.h"
28 #include "clang/Analysis/CFG.h"
29 #include "clang/Analysis/CFGStmtMap.h"
30 #include "clang/Analysis/PathDiagnostic.h"
31 #include "clang/Analysis/ProgramPoint.h"
32 #include "clang/Basic/LLVM.h"
33 #include "clang/Basic/SourceLocation.h"
34 #include "clang/Basic/SourceManager.h"
35 #include "clang/StaticAnalyzer/Core/AnalyzerOptions.h"
36 #include "clang/StaticAnalyzer/Core/BugReporter/BugReporterVisitors.h"
37 #include "clang/StaticAnalyzer/Core/BugReporter/BugType.h"
38 #include "clang/StaticAnalyzer/Core/BugReporter/Z3CrosscheckVisitor.h"
39 #include "clang/StaticAnalyzer/Core/Checker.h"
40 #include "clang/StaticAnalyzer/Core/CheckerManager.h"
41 #include "clang/StaticAnalyzer/Core/CheckerRegistryData.h"
42 #include "clang/StaticAnalyzer/Core/PathSensitive/ExplodedGraph.h"
43 #include "clang/StaticAnalyzer/Core/PathSensitive/ExprEngine.h"
44 #include "clang/StaticAnalyzer/Core/PathSensitive/MemRegion.h"
45 #include "clang/StaticAnalyzer/Core/PathSensitive/ProgramState.h"
46 #include "clang/StaticAnalyzer/Core/PathSensitive/SMTConv.h"
47 #include "clang/StaticAnalyzer/Core/PathSensitive/SVals.h"
48 #include "clang/StaticAnalyzer/Core/PathSensitive/SymbolManager.h"
49 #include "llvm/ADT/ArrayRef.h"
50 #include "llvm/ADT/DenseMap.h"
51 #include "llvm/ADT/DenseSet.h"
52 #include "llvm/ADT/FoldingSet.h"
53 #include "llvm/ADT/STLExtras.h"
54 #include "llvm/ADT/SmallPtrSet.h"
55 #include "llvm/ADT/SmallString.h"
56 #include "llvm/ADT/SmallVector.h"
57 #include "llvm/ADT/Statistic.h"
58 #include "llvm/ADT/StringExtras.h"
59 #include "llvm/ADT/StringRef.h"
60 #include "llvm/ADT/iterator_range.h"
61 #include "llvm/Support/Casting.h"
62 #include "llvm/Support/Compiler.h"
63 #include "llvm/Support/ErrorHandling.h"
64 #include "llvm/Support/MemoryBuffer.h"
65 #include "llvm/Support/raw_ostream.h"
66 #include <algorithm>
67 #include <cassert>
68 #include <cstddef>
69 #include <iterator>
70 #include <memory>
71 #include <optional>
72 #include <queue>
73 #include <string>
74 #include <tuple>
75 #include <utility>
76 #include <vector>
78 using namespace clang;
79 using namespace ento;
80 using namespace llvm;
82 #define DEBUG_TYPE "BugReporter"
84 STATISTIC(MaxBugClassSize,
85 "The maximum number of bug reports in the same equivalence class");
86 STATISTIC(MaxValidBugClassSize,
87 "The maximum number of bug reports in the same equivalence class "
88 "where at least one report is valid (not suppressed)");
90 STATISTIC(NumTimesReportPassesZ3, "Number of reports passed Z3");
91 STATISTIC(NumTimesReportRefuted, "Number of reports refuted by Z3");
92 STATISTIC(NumTimesReportEQClassAborted,
93 "Number of times a report equivalence class was aborted by the Z3 "
94 "oracle heuristic");
95 STATISTIC(NumTimesReportEQClassWasExhausted,
96 "Number of times all reports of an equivalence class was refuted");
98 BugReporterVisitor::~BugReporterVisitor() = default;
100 void BugReporterContext::anchor() {}
102 //===----------------------------------------------------------------------===//
103 // PathDiagnosticBuilder and its associated routines and helper objects.
104 //===----------------------------------------------------------------------===//
106 namespace {
108 /// A (CallPiece, node assiciated with its CallEnter) pair.
109 using CallWithEntry =
110 std::pair<PathDiagnosticCallPiece *, const ExplodedNode *>;
111 using CallWithEntryStack = SmallVector<CallWithEntry, 6>;
113 /// Map from each node to the diagnostic pieces visitors emit for them.
114 using VisitorsDiagnosticsTy =
115 llvm::DenseMap<const ExplodedNode *, std::vector<PathDiagnosticPieceRef>>;
117 /// A map from PathDiagnosticPiece to the LocationContext of the inlined
118 /// function call it represents.
119 using LocationContextMap =
120 llvm::DenseMap<const PathPieces *, const LocationContext *>;
122 /// A helper class that contains everything needed to construct a
123 /// PathDiagnostic object. It does no much more then providing convenient
124 /// getters and some well placed asserts for extra security.
125 class PathDiagnosticConstruct {
126 /// The consumer we're constructing the bug report for.
127 const PathDiagnosticConsumer *Consumer;
128 /// Our current position in the bug path, which is owned by
129 /// PathDiagnosticBuilder.
130 const ExplodedNode *CurrentNode;
131 /// A mapping from parts of the bug path (for example, a function call, which
132 /// would span backwards from a CallExit to a CallEnter with the nodes in
133 /// between them) with the location contexts it is associated with.
134 LocationContextMap LCM;
135 const SourceManager &SM;
137 public:
138 /// We keep stack of calls to functions as we're ascending the bug path.
139 /// TODO: PathDiagnostic has a stack doing the same thing, shouldn't we use
140 /// that instead?
141 CallWithEntryStack CallStack;
142 /// The bug report we're constructing. For ease of use, this field is kept
143 /// public, though some "shortcut" getters are provided for commonly used
144 /// methods of PathDiagnostic.
145 std::unique_ptr<PathDiagnostic> PD;
147 public:
148 PathDiagnosticConstruct(const PathDiagnosticConsumer *PDC,
149 const ExplodedNode *ErrorNode,
150 const PathSensitiveBugReport *R,
151 const Decl *AnalysisEntryPoint);
153 /// \returns the location context associated with the current position in the
154 /// bug path.
155 const LocationContext *getCurrLocationContext() const {
156 assert(CurrentNode && "Already reached the root!");
157 return CurrentNode->getLocationContext();
160 /// Same as getCurrLocationContext (they should always return the same
161 /// location context), but works after reaching the root of the bug path as
162 /// well.
163 const LocationContext *getLocationContextForActivePath() const {
164 return LCM.find(&PD->getActivePath())->getSecond();
167 const ExplodedNode *getCurrentNode() const { return CurrentNode; }
169 /// Steps the current node to its predecessor.
170 /// \returns whether we reached the root of the bug path.
171 bool ascendToPrevNode() {
172 CurrentNode = CurrentNode->getFirstPred();
173 return static_cast<bool>(CurrentNode);
176 const ParentMap &getParentMap() const {
177 return getCurrLocationContext()->getParentMap();
180 const SourceManager &getSourceManager() const { return SM; }
182 const Stmt *getParent(const Stmt *S) const {
183 return getParentMap().getParent(S);
186 void updateLocCtxMap(const PathPieces *Path, const LocationContext *LC) {
187 assert(Path && LC);
188 LCM[Path] = LC;
191 const LocationContext *getLocationContextFor(const PathPieces *Path) const {
192 assert(LCM.count(Path) &&
193 "Failed to find the context associated with these pieces!");
194 return LCM.find(Path)->getSecond();
197 bool isInLocCtxMap(const PathPieces *Path) const { return LCM.count(Path); }
199 PathPieces &getActivePath() { return PD->getActivePath(); }
200 PathPieces &getMutablePieces() { return PD->getMutablePieces(); }
202 bool shouldAddPathEdges() const { return Consumer->shouldAddPathEdges(); }
203 bool shouldAddControlNotes() const {
204 return Consumer->shouldAddControlNotes();
206 bool shouldGenerateDiagnostics() const {
207 return Consumer->shouldGenerateDiagnostics();
209 bool supportsLogicalOpControlFlow() const {
210 return Consumer->supportsLogicalOpControlFlow();
214 /// Contains every contextual information needed for constructing a
215 /// PathDiagnostic object for a given bug report. This class and its fields are
216 /// immutable, and passes a BugReportConstruct object around during the
217 /// construction.
218 class PathDiagnosticBuilder : public BugReporterContext {
219 /// A linear path from the error node to the root.
220 std::unique_ptr<const ExplodedGraph> BugPath;
221 /// The bug report we're describing. Visitors create their diagnostics with
222 /// them being the last entities being able to modify it (for example,
223 /// changing interestingness here would cause inconsistencies as to how this
224 /// file and visitors construct diagnostics), hence its const.
225 const PathSensitiveBugReport *R;
226 /// The leaf of the bug path. This isn't the same as the bug reports error
227 /// node, which refers to the *original* graph, not the bug path.
228 const ExplodedNode *const ErrorNode;
229 /// The diagnostic pieces visitors emitted, which is expected to be collected
230 /// by the time this builder is constructed.
231 std::unique_ptr<const VisitorsDiagnosticsTy> VisitorsDiagnostics;
233 public:
234 /// Find a non-invalidated report for a given equivalence class, and returns
235 /// a PathDiagnosticBuilder able to construct bug reports for different
236 /// consumers. Returns std::nullopt if no valid report is found.
237 static std::optional<PathDiagnosticBuilder>
238 findValidReport(ArrayRef<PathSensitiveBugReport *> &bugReports,
239 PathSensitiveBugReporter &Reporter);
241 PathDiagnosticBuilder(
242 BugReporterContext BRC, std::unique_ptr<ExplodedGraph> BugPath,
243 PathSensitiveBugReport *r, const ExplodedNode *ErrorNode,
244 std::unique_ptr<VisitorsDiagnosticsTy> VisitorsDiagnostics);
246 /// This function is responsible for generating diagnostic pieces that are
247 /// *not* provided by bug report visitors.
248 /// These diagnostics may differ depending on the consumer's settings,
249 /// and are therefore constructed separately for each consumer.
251 /// There are two path diagnostics generation modes: with adding edges (used
252 /// for plists) and without (used for HTML and text). When edges are added,
253 /// the path is modified to insert artificially generated edges.
254 /// Otherwise, more detailed diagnostics is emitted for block edges,
255 /// explaining the transitions in words.
256 std::unique_ptr<PathDiagnostic>
257 generate(const PathDiagnosticConsumer *PDC) const;
259 private:
260 void updateStackPiecesWithMessage(PathDiagnosticPieceRef P,
261 const CallWithEntryStack &CallStack) const;
262 void generatePathDiagnosticsForNode(PathDiagnosticConstruct &C,
263 PathDiagnosticLocation &PrevLoc) const;
265 void generateMinimalDiagForBlockEdge(PathDiagnosticConstruct &C,
266 BlockEdge BE) const;
268 PathDiagnosticPieceRef
269 generateDiagForGotoOP(const PathDiagnosticConstruct &C, const Stmt *S,
270 PathDiagnosticLocation &Start) const;
272 PathDiagnosticPieceRef
273 generateDiagForSwitchOP(const PathDiagnosticConstruct &C, const CFGBlock *Dst,
274 PathDiagnosticLocation &Start) const;
276 PathDiagnosticPieceRef
277 generateDiagForBinaryOP(const PathDiagnosticConstruct &C, const Stmt *T,
278 const CFGBlock *Src, const CFGBlock *DstC) const;
280 PathDiagnosticLocation
281 ExecutionContinues(const PathDiagnosticConstruct &C) const;
283 PathDiagnosticLocation
284 ExecutionContinues(llvm::raw_string_ostream &os,
285 const PathDiagnosticConstruct &C) const;
287 const PathSensitiveBugReport *getBugReport() const { return R; }
290 } // namespace
292 //===----------------------------------------------------------------------===//
293 // Base implementation of stack hint generators.
294 //===----------------------------------------------------------------------===//
296 StackHintGenerator::~StackHintGenerator() = default;
298 std::string StackHintGeneratorForSymbol::getMessage(const ExplodedNode *N){
299 if (!N)
300 return getMessageForSymbolNotFound();
302 ProgramPoint P = N->getLocation();
303 CallExitEnd CExit = P.castAs<CallExitEnd>();
305 // FIXME: Use CallEvent to abstract this over all calls.
306 const Stmt *CallSite = CExit.getCalleeContext()->getCallSite();
307 const auto *CE = dyn_cast_or_null<CallExpr>(CallSite);
308 if (!CE)
309 return {};
311 // Check if one of the parameters are set to the interesting symbol.
312 for (auto [Idx, ArgExpr] : llvm::enumerate(CE->arguments())) {
313 SVal SV = N->getSVal(ArgExpr);
315 // Check if the variable corresponding to the symbol is passed by value.
316 SymbolRef AS = SV.getAsLocSymbol();
317 if (AS == Sym) {
318 return getMessageForArg(ArgExpr, Idx);
321 // Check if the parameter is a pointer to the symbol.
322 if (std::optional<loc::MemRegionVal> Reg = SV.getAs<loc::MemRegionVal>()) {
323 // Do not attempt to dereference void*.
324 if (ArgExpr->getType()->isVoidPointerType())
325 continue;
326 SVal PSV = N->getState()->getSVal(Reg->getRegion());
327 SymbolRef AS = PSV.getAsLocSymbol();
328 if (AS == Sym) {
329 return getMessageForArg(ArgExpr, Idx);
334 // Check if we are returning the interesting symbol.
335 SVal SV = N->getSVal(CE);
336 SymbolRef RetSym = SV.getAsLocSymbol();
337 if (RetSym == Sym) {
338 return getMessageForReturn(CE);
341 return getMessageForSymbolNotFound();
344 std::string StackHintGeneratorForSymbol::getMessageForArg(const Expr *ArgE,
345 unsigned ArgIndex) {
346 // Printed parameters start at 1, not 0.
347 ++ArgIndex;
349 return (llvm::Twine(Msg) + " via " + std::to_string(ArgIndex) +
350 llvm::getOrdinalSuffix(ArgIndex) + " parameter").str();
353 //===----------------------------------------------------------------------===//
354 // Diagnostic cleanup.
355 //===----------------------------------------------------------------------===//
357 static PathDiagnosticEventPiece *
358 eventsDescribeSameCondition(PathDiagnosticEventPiece *X,
359 PathDiagnosticEventPiece *Y) {
360 // Prefer diagnostics that come from ConditionBRVisitor over
361 // those that came from TrackConstraintBRVisitor,
362 // unless the one from ConditionBRVisitor is
363 // its generic fallback diagnostic.
364 const void *tagPreferred = ConditionBRVisitor::getTag();
365 const void *tagLesser = TrackConstraintBRVisitor::getTag();
367 if (X->getLocation() != Y->getLocation())
368 return nullptr;
370 if (X->getTag() == tagPreferred && Y->getTag() == tagLesser)
371 return ConditionBRVisitor::isPieceMessageGeneric(X) ? Y : X;
373 if (Y->getTag() == tagPreferred && X->getTag() == tagLesser)
374 return ConditionBRVisitor::isPieceMessageGeneric(Y) ? X : Y;
376 return nullptr;
379 /// An optimization pass over PathPieces that removes redundant diagnostics
380 /// generated by both ConditionBRVisitor and TrackConstraintBRVisitor. Both
381 /// BugReporterVisitors use different methods to generate diagnostics, with
382 /// one capable of emitting diagnostics in some cases but not in others. This
383 /// can lead to redundant diagnostic pieces at the same point in a path.
384 static void removeRedundantMsgs(PathPieces &path) {
385 unsigned N = path.size();
386 if (N < 2)
387 return;
388 // NOTE: this loop intentionally is not using an iterator. Instead, we
389 // are streaming the path and modifying it in place. This is done by
390 // grabbing the front, processing it, and if we decide to keep it append
391 // it to the end of the path. The entire path is processed in this way.
392 for (unsigned i = 0; i < N; ++i) {
393 auto piece = std::move(path.front());
394 path.pop_front();
396 switch (piece->getKind()) {
397 case PathDiagnosticPiece::Call:
398 removeRedundantMsgs(cast<PathDiagnosticCallPiece>(*piece).path);
399 break;
400 case PathDiagnosticPiece::Macro:
401 removeRedundantMsgs(cast<PathDiagnosticMacroPiece>(*piece).subPieces);
402 break;
403 case PathDiagnosticPiece::Event: {
404 if (i == N-1)
405 break;
407 if (auto *nextEvent =
408 dyn_cast<PathDiagnosticEventPiece>(path.front().get())) {
409 auto *event = cast<PathDiagnosticEventPiece>(piece.get());
410 // Check to see if we should keep one of the two pieces. If we
411 // come up with a preference, record which piece to keep, and consume
412 // another piece from the path.
413 if (auto *pieceToKeep =
414 eventsDescribeSameCondition(event, nextEvent)) {
415 piece = std::move(pieceToKeep == event ? piece : path.front());
416 path.pop_front();
417 ++i;
420 break;
422 case PathDiagnosticPiece::ControlFlow:
423 case PathDiagnosticPiece::Note:
424 case PathDiagnosticPiece::PopUp:
425 break;
427 path.push_back(std::move(piece));
431 /// Recursively scan through a path and prune out calls and macros pieces
432 /// that aren't needed. Return true if afterwards the path contains
433 /// "interesting stuff" which means it shouldn't be pruned from the parent path.
434 static bool removeUnneededCalls(const PathDiagnosticConstruct &C,
435 PathPieces &pieces,
436 const PathSensitiveBugReport *R,
437 bool IsInteresting = false) {
438 bool containsSomethingInteresting = IsInteresting;
439 const unsigned N = pieces.size();
441 for (unsigned i = 0 ; i < N ; ++i) {
442 // Remove the front piece from the path. If it is still something we
443 // want to keep once we are done, we will push it back on the end.
444 auto piece = std::move(pieces.front());
445 pieces.pop_front();
447 switch (piece->getKind()) {
448 case PathDiagnosticPiece::Call: {
449 auto &call = cast<PathDiagnosticCallPiece>(*piece);
450 // Check if the location context is interesting.
451 if (!removeUnneededCalls(
452 C, call.path, R,
453 R->isInteresting(C.getLocationContextFor(&call.path))))
454 continue;
456 containsSomethingInteresting = true;
457 break;
459 case PathDiagnosticPiece::Macro: {
460 auto &macro = cast<PathDiagnosticMacroPiece>(*piece);
461 if (!removeUnneededCalls(C, macro.subPieces, R, IsInteresting))
462 continue;
463 containsSomethingInteresting = true;
464 break;
466 case PathDiagnosticPiece::Event: {
467 auto &event = cast<PathDiagnosticEventPiece>(*piece);
469 // We never throw away an event, but we do throw it away wholesale
470 // as part of a path if we throw the entire path away.
471 containsSomethingInteresting |= !event.isPrunable();
472 break;
474 case PathDiagnosticPiece::ControlFlow:
475 case PathDiagnosticPiece::Note:
476 case PathDiagnosticPiece::PopUp:
477 break;
480 pieces.push_back(std::move(piece));
483 return containsSomethingInteresting;
486 /// Same logic as above to remove extra pieces.
487 static void removePopUpNotes(PathPieces &Path) {
488 for (unsigned int i = 0; i < Path.size(); ++i) {
489 auto Piece = std::move(Path.front());
490 Path.pop_front();
491 if (!isa<PathDiagnosticPopUpPiece>(*Piece))
492 Path.push_back(std::move(Piece));
496 /// Returns true if the given decl has been implicitly given a body, either by
497 /// the analyzer or by the compiler proper.
498 static bool hasImplicitBody(const Decl *D) {
499 assert(D);
500 return D->isImplicit() || !D->hasBody();
503 /// Recursively scan through a path and make sure that all call pieces have
504 /// valid locations.
505 static void
506 adjustCallLocations(PathPieces &Pieces,
507 PathDiagnosticLocation *LastCallLocation = nullptr) {
508 for (const auto &I : Pieces) {
509 auto *Call = dyn_cast<PathDiagnosticCallPiece>(I.get());
511 if (!Call)
512 continue;
514 if (LastCallLocation) {
515 bool CallerIsImplicit = hasImplicitBody(Call->getCaller());
516 if (CallerIsImplicit || !Call->callEnter.asLocation().isValid())
517 Call->callEnter = *LastCallLocation;
518 if (CallerIsImplicit || !Call->callReturn.asLocation().isValid())
519 Call->callReturn = *LastCallLocation;
522 // Recursively clean out the subclass. Keep this call around if
523 // it contains any informative diagnostics.
524 PathDiagnosticLocation *ThisCallLocation;
525 if (Call->callEnterWithin.asLocation().isValid() &&
526 !hasImplicitBody(Call->getCallee()))
527 ThisCallLocation = &Call->callEnterWithin;
528 else
529 ThisCallLocation = &Call->callEnter;
531 assert(ThisCallLocation && "Outermost call has an invalid location");
532 adjustCallLocations(Call->path, ThisCallLocation);
536 /// Remove edges in and out of C++ default initializer expressions. These are
537 /// for fields that have in-class initializers, as opposed to being initialized
538 /// explicitly in a constructor or braced list.
539 static void removeEdgesToDefaultInitializers(PathPieces &Pieces) {
540 for (PathPieces::iterator I = Pieces.begin(), E = Pieces.end(); I != E;) {
541 if (auto *C = dyn_cast<PathDiagnosticCallPiece>(I->get()))
542 removeEdgesToDefaultInitializers(C->path);
544 if (auto *M = dyn_cast<PathDiagnosticMacroPiece>(I->get()))
545 removeEdgesToDefaultInitializers(M->subPieces);
547 if (auto *CF = dyn_cast<PathDiagnosticControlFlowPiece>(I->get())) {
548 const Stmt *Start = CF->getStartLocation().asStmt();
549 const Stmt *End = CF->getEndLocation().asStmt();
550 if (isa_and_nonnull<CXXDefaultInitExpr>(Start)) {
551 I = Pieces.erase(I);
552 continue;
553 } else if (isa_and_nonnull<CXXDefaultInitExpr>(End)) {
554 PathPieces::iterator Next = std::next(I);
555 if (Next != E) {
556 if (auto *NextCF =
557 dyn_cast<PathDiagnosticControlFlowPiece>(Next->get())) {
558 NextCF->setStartLocation(CF->getStartLocation());
561 I = Pieces.erase(I);
562 continue;
566 I++;
570 /// Remove all pieces with invalid locations as these cannot be serialized.
571 /// We might have pieces with invalid locations as a result of inlining Body
572 /// Farm generated functions.
573 static void removePiecesWithInvalidLocations(PathPieces &Pieces) {
574 for (PathPieces::iterator I = Pieces.begin(), E = Pieces.end(); I != E;) {
575 if (auto *C = dyn_cast<PathDiagnosticCallPiece>(I->get()))
576 removePiecesWithInvalidLocations(C->path);
578 if (auto *M = dyn_cast<PathDiagnosticMacroPiece>(I->get()))
579 removePiecesWithInvalidLocations(M->subPieces);
581 if (!(*I)->getLocation().isValid() ||
582 !(*I)->getLocation().asLocation().isValid()) {
583 I = Pieces.erase(I);
584 continue;
586 I++;
590 PathDiagnosticLocation PathDiagnosticBuilder::ExecutionContinues(
591 const PathDiagnosticConstruct &C) const {
592 if (const Stmt *S = C.getCurrentNode()->getNextStmtForDiagnostics())
593 return PathDiagnosticLocation(S, getSourceManager(),
594 C.getCurrLocationContext());
596 return PathDiagnosticLocation::createDeclEnd(C.getCurrLocationContext(),
597 getSourceManager());
600 PathDiagnosticLocation PathDiagnosticBuilder::ExecutionContinues(
601 llvm::raw_string_ostream &os, const PathDiagnosticConstruct &C) const {
602 // Slow, but probably doesn't matter.
603 if (os.str().empty())
604 os << ' ';
606 const PathDiagnosticLocation &Loc = ExecutionContinues(C);
608 if (Loc.asStmt())
609 os << "Execution continues on line "
610 << getSourceManager().getExpansionLineNumber(Loc.asLocation())
611 << '.';
612 else {
613 os << "Execution jumps to the end of the ";
614 const Decl *D = C.getCurrLocationContext()->getDecl();
615 if (isa<ObjCMethodDecl>(D))
616 os << "method";
617 else if (isa<FunctionDecl>(D))
618 os << "function";
619 else {
620 assert(isa<BlockDecl>(D));
621 os << "anonymous block";
623 os << '.';
626 return Loc;
629 static const Stmt *getEnclosingParent(const Stmt *S, const ParentMap &PM) {
630 if (isa<Expr>(S) && PM.isConsumedExpr(cast<Expr>(S)))
631 return PM.getParentIgnoreParens(S);
633 const Stmt *Parent = PM.getParentIgnoreParens(S);
634 if (!Parent)
635 return nullptr;
637 switch (Parent->getStmtClass()) {
638 case Stmt::ForStmtClass:
639 case Stmt::DoStmtClass:
640 case Stmt::WhileStmtClass:
641 case Stmt::ObjCForCollectionStmtClass:
642 case Stmt::CXXForRangeStmtClass:
643 return Parent;
644 default:
645 break;
648 return nullptr;
651 static PathDiagnosticLocation
652 getEnclosingStmtLocation(const Stmt *S, const LocationContext *LC,
653 bool allowNestedContexts = false) {
654 if (!S)
655 return {};
657 const SourceManager &SMgr = LC->getDecl()->getASTContext().getSourceManager();
659 while (const Stmt *Parent = getEnclosingParent(S, LC->getParentMap())) {
660 switch (Parent->getStmtClass()) {
661 case Stmt::BinaryOperatorClass: {
662 const auto *B = cast<BinaryOperator>(Parent);
663 if (B->isLogicalOp())
664 return PathDiagnosticLocation(allowNestedContexts ? B : S, SMgr, LC);
665 break;
667 case Stmt::CompoundStmtClass:
668 case Stmt::StmtExprClass:
669 return PathDiagnosticLocation(S, SMgr, LC);
670 case Stmt::ChooseExprClass:
671 // Similar to '?' if we are referring to condition, just have the edge
672 // point to the entire choose expression.
673 if (allowNestedContexts || cast<ChooseExpr>(Parent)->getCond() == S)
674 return PathDiagnosticLocation(Parent, SMgr, LC);
675 else
676 return PathDiagnosticLocation(S, SMgr, LC);
677 case Stmt::BinaryConditionalOperatorClass:
678 case Stmt::ConditionalOperatorClass:
679 // For '?', if we are referring to condition, just have the edge point
680 // to the entire '?' expression.
681 if (allowNestedContexts ||
682 cast<AbstractConditionalOperator>(Parent)->getCond() == S)
683 return PathDiagnosticLocation(Parent, SMgr, LC);
684 else
685 return PathDiagnosticLocation(S, SMgr, LC);
686 case Stmt::CXXForRangeStmtClass:
687 if (cast<CXXForRangeStmt>(Parent)->getBody() == S)
688 return PathDiagnosticLocation(S, SMgr, LC);
689 break;
690 case Stmt::DoStmtClass:
691 return PathDiagnosticLocation(S, SMgr, LC);
692 case Stmt::ForStmtClass:
693 if (cast<ForStmt>(Parent)->getBody() == S)
694 return PathDiagnosticLocation(S, SMgr, LC);
695 break;
696 case Stmt::IfStmtClass:
697 if (cast<IfStmt>(Parent)->getCond() != S)
698 return PathDiagnosticLocation(S, SMgr, LC);
699 break;
700 case Stmt::ObjCForCollectionStmtClass:
701 if (cast<ObjCForCollectionStmt>(Parent)->getBody() == S)
702 return PathDiagnosticLocation(S, SMgr, LC);
703 break;
704 case Stmt::WhileStmtClass:
705 if (cast<WhileStmt>(Parent)->getCond() != S)
706 return PathDiagnosticLocation(S, SMgr, LC);
707 break;
708 default:
709 break;
712 S = Parent;
715 assert(S && "Cannot have null Stmt for PathDiagnosticLocation");
717 return PathDiagnosticLocation(S, SMgr, LC);
720 //===----------------------------------------------------------------------===//
721 // "Minimal" path diagnostic generation algorithm.
722 //===----------------------------------------------------------------------===//
724 /// If the piece contains a special message, add it to all the call pieces on
725 /// the active stack. For example, my_malloc allocated memory, so MallocChecker
726 /// will construct an event at the call to malloc(), and add a stack hint that
727 /// an allocated memory was returned. We'll use this hint to construct a message
728 /// when returning from the call to my_malloc
730 /// void *my_malloc() { return malloc(sizeof(int)); }
731 /// void fishy() {
732 /// void *ptr = my_malloc(); // returned allocated memory
733 /// } // leak
734 void PathDiagnosticBuilder::updateStackPiecesWithMessage(
735 PathDiagnosticPieceRef P, const CallWithEntryStack &CallStack) const {
736 if (R->hasCallStackHint(P))
737 for (const auto &I : CallStack) {
738 PathDiagnosticCallPiece *CP = I.first;
739 const ExplodedNode *N = I.second;
740 std::string stackMsg = R->getCallStackMessage(P, N);
742 // The last message on the path to final bug is the most important
743 // one. Since we traverse the path backwards, do not add the message
744 // if one has been previously added.
745 if (!CP->hasCallStackMessage())
746 CP->setCallStackMessage(stackMsg);
750 static void CompactMacroExpandedPieces(PathPieces &path,
751 const SourceManager& SM);
753 PathDiagnosticPieceRef PathDiagnosticBuilder::generateDiagForSwitchOP(
754 const PathDiagnosticConstruct &C, const CFGBlock *Dst,
755 PathDiagnosticLocation &Start) const {
757 const SourceManager &SM = getSourceManager();
758 // Figure out what case arm we took.
759 std::string sbuf;
760 llvm::raw_string_ostream os(sbuf);
761 PathDiagnosticLocation End;
763 if (const Stmt *S = Dst->getLabel()) {
764 End = PathDiagnosticLocation(S, SM, C.getCurrLocationContext());
766 switch (S->getStmtClass()) {
767 default:
768 os << "No cases match in the switch statement. "
769 "Control jumps to line "
770 << End.asLocation().getExpansionLineNumber();
771 break;
772 case Stmt::DefaultStmtClass:
773 os << "Control jumps to the 'default' case at line "
774 << End.asLocation().getExpansionLineNumber();
775 break;
777 case Stmt::CaseStmtClass: {
778 os << "Control jumps to 'case ";
779 const auto *Case = cast<CaseStmt>(S);
780 const Expr *LHS = Case->getLHS()->IgnoreParenImpCasts();
782 // Determine if it is an enum.
783 bool GetRawInt = true;
785 if (const auto *DR = dyn_cast<DeclRefExpr>(LHS)) {
786 // FIXME: Maybe this should be an assertion. Are there cases
787 // were it is not an EnumConstantDecl?
788 const auto *D = dyn_cast<EnumConstantDecl>(DR->getDecl());
790 if (D) {
791 GetRawInt = false;
792 os << *D;
796 if (GetRawInt)
797 os << LHS->EvaluateKnownConstInt(getASTContext());
799 os << ":' at line " << End.asLocation().getExpansionLineNumber();
800 break;
803 } else {
804 os << "'Default' branch taken. ";
805 End = ExecutionContinues(os, C);
807 return std::make_shared<PathDiagnosticControlFlowPiece>(Start, End, sbuf);
810 PathDiagnosticPieceRef PathDiagnosticBuilder::generateDiagForGotoOP(
811 const PathDiagnosticConstruct &C, const Stmt *S,
812 PathDiagnosticLocation &Start) const {
813 std::string sbuf;
814 llvm::raw_string_ostream os(sbuf);
815 const PathDiagnosticLocation &End =
816 getEnclosingStmtLocation(S, C.getCurrLocationContext());
817 os << "Control jumps to line " << End.asLocation().getExpansionLineNumber();
818 return std::make_shared<PathDiagnosticControlFlowPiece>(Start, End, sbuf);
821 PathDiagnosticPieceRef PathDiagnosticBuilder::generateDiagForBinaryOP(
822 const PathDiagnosticConstruct &C, const Stmt *T, const CFGBlock *Src,
823 const CFGBlock *Dst) const {
825 const SourceManager &SM = getSourceManager();
827 const auto *B = cast<BinaryOperator>(T);
828 std::string sbuf;
829 llvm::raw_string_ostream os(sbuf);
830 os << "Left side of '";
831 PathDiagnosticLocation Start, End;
833 if (B->getOpcode() == BO_LAnd) {
834 os << "&&"
835 << "' is ";
837 if (*(Src->succ_begin() + 1) == Dst) {
838 os << "false";
839 End = PathDiagnosticLocation(B->getLHS(), SM, C.getCurrLocationContext());
840 Start =
841 PathDiagnosticLocation::createOperatorLoc(B, SM);
842 } else {
843 os << "true";
844 Start =
845 PathDiagnosticLocation(B->getLHS(), SM, C.getCurrLocationContext());
846 End = ExecutionContinues(C);
848 } else {
849 assert(B->getOpcode() == BO_LOr);
850 os << "||"
851 << "' is ";
853 if (*(Src->succ_begin() + 1) == Dst) {
854 os << "false";
855 Start =
856 PathDiagnosticLocation(B->getLHS(), SM, C.getCurrLocationContext());
857 End = ExecutionContinues(C);
858 } else {
859 os << "true";
860 End = PathDiagnosticLocation(B->getLHS(), SM, C.getCurrLocationContext());
861 Start =
862 PathDiagnosticLocation::createOperatorLoc(B, SM);
865 return std::make_shared<PathDiagnosticControlFlowPiece>(Start, End, sbuf);
868 void PathDiagnosticBuilder::generateMinimalDiagForBlockEdge(
869 PathDiagnosticConstruct &C, BlockEdge BE) const {
870 const SourceManager &SM = getSourceManager();
871 const LocationContext *LC = C.getCurrLocationContext();
872 const CFGBlock *Src = BE.getSrc();
873 const CFGBlock *Dst = BE.getDst();
874 const Stmt *T = Src->getTerminatorStmt();
875 if (!T)
876 return;
878 auto Start = PathDiagnosticLocation::createBegin(T, SM, LC);
879 switch (T->getStmtClass()) {
880 default:
881 break;
883 case Stmt::GotoStmtClass:
884 case Stmt::IndirectGotoStmtClass: {
885 if (const Stmt *S = C.getCurrentNode()->getNextStmtForDiagnostics())
886 C.getActivePath().push_front(generateDiagForGotoOP(C, S, Start));
887 break;
890 case Stmt::SwitchStmtClass: {
891 C.getActivePath().push_front(generateDiagForSwitchOP(C, Dst, Start));
892 break;
895 case Stmt::BreakStmtClass:
896 case Stmt::ContinueStmtClass: {
897 std::string sbuf;
898 llvm::raw_string_ostream os(sbuf);
899 PathDiagnosticLocation End = ExecutionContinues(os, C);
900 C.getActivePath().push_front(
901 std::make_shared<PathDiagnosticControlFlowPiece>(Start, End, sbuf));
902 break;
905 // Determine control-flow for ternary '?'.
906 case Stmt::BinaryConditionalOperatorClass:
907 case Stmt::ConditionalOperatorClass: {
908 std::string sbuf;
909 llvm::raw_string_ostream os(sbuf);
910 os << "'?' condition is ";
912 if (*(Src->succ_begin() + 1) == Dst)
913 os << "false";
914 else
915 os << "true";
917 PathDiagnosticLocation End = ExecutionContinues(C);
919 if (const Stmt *S = End.asStmt())
920 End = getEnclosingStmtLocation(S, C.getCurrLocationContext());
922 C.getActivePath().push_front(
923 std::make_shared<PathDiagnosticControlFlowPiece>(Start, End, sbuf));
924 break;
927 // Determine control-flow for short-circuited '&&' and '||'.
928 case Stmt::BinaryOperatorClass: {
929 if (!C.supportsLogicalOpControlFlow())
930 break;
932 C.getActivePath().push_front(generateDiagForBinaryOP(C, T, Src, Dst));
933 break;
936 case Stmt::DoStmtClass:
937 if (*(Src->succ_begin()) == Dst) {
938 std::string sbuf;
939 llvm::raw_string_ostream os(sbuf);
941 os << "Loop condition is true. ";
942 PathDiagnosticLocation End = ExecutionContinues(os, C);
944 if (const Stmt *S = End.asStmt())
945 End = getEnclosingStmtLocation(S, C.getCurrLocationContext());
947 C.getActivePath().push_front(
948 std::make_shared<PathDiagnosticControlFlowPiece>(Start, End, sbuf));
949 } else {
950 PathDiagnosticLocation End = ExecutionContinues(C);
952 if (const Stmt *S = End.asStmt())
953 End = getEnclosingStmtLocation(S, C.getCurrLocationContext());
955 C.getActivePath().push_front(
956 std::make_shared<PathDiagnosticControlFlowPiece>(
957 Start, End, "Loop condition is false. Exiting loop"));
959 break;
961 case Stmt::WhileStmtClass:
962 case Stmt::ForStmtClass:
963 if (*(Src->succ_begin() + 1) == Dst) {
964 std::string sbuf;
965 llvm::raw_string_ostream os(sbuf);
967 os << "Loop condition is false. ";
968 PathDiagnosticLocation End = ExecutionContinues(os, C);
969 if (const Stmt *S = End.asStmt())
970 End = getEnclosingStmtLocation(S, C.getCurrLocationContext());
972 C.getActivePath().push_front(
973 std::make_shared<PathDiagnosticControlFlowPiece>(Start, End, sbuf));
974 } else {
975 PathDiagnosticLocation End = ExecutionContinues(C);
976 if (const Stmt *S = End.asStmt())
977 End = getEnclosingStmtLocation(S, C.getCurrLocationContext());
979 C.getActivePath().push_front(
980 std::make_shared<PathDiagnosticControlFlowPiece>(
981 Start, End, "Loop condition is true. Entering loop body"));
984 break;
986 case Stmt::IfStmtClass: {
987 PathDiagnosticLocation End = ExecutionContinues(C);
989 if (const Stmt *S = End.asStmt())
990 End = getEnclosingStmtLocation(S, C.getCurrLocationContext());
992 if (*(Src->succ_begin() + 1) == Dst)
993 C.getActivePath().push_front(
994 std::make_shared<PathDiagnosticControlFlowPiece>(
995 Start, End, "Taking false branch"));
996 else
997 C.getActivePath().push_front(
998 std::make_shared<PathDiagnosticControlFlowPiece>(
999 Start, End, "Taking true branch"));
1001 break;
1006 //===----------------------------------------------------------------------===//
1007 // Functions for determining if a loop was executed 0 times.
1008 //===----------------------------------------------------------------------===//
1010 static bool isLoop(const Stmt *Term) {
1011 switch (Term->getStmtClass()) {
1012 case Stmt::ForStmtClass:
1013 case Stmt::WhileStmtClass:
1014 case Stmt::ObjCForCollectionStmtClass:
1015 case Stmt::CXXForRangeStmtClass:
1016 return true;
1017 default:
1018 // Note that we intentionally do not include do..while here.
1019 return false;
1023 static bool isJumpToFalseBranch(const BlockEdge *BE) {
1024 const CFGBlock *Src = BE->getSrc();
1025 assert(Src->succ_size() == 2);
1026 return (*(Src->succ_begin()+1) == BE->getDst());
1029 static bool isContainedByStmt(const ParentMap &PM, const Stmt *S,
1030 const Stmt *SubS) {
1031 while (SubS) {
1032 if (SubS == S)
1033 return true;
1034 SubS = PM.getParent(SubS);
1036 return false;
1039 static const Stmt *getStmtBeforeCond(const ParentMap &PM, const Stmt *Term,
1040 const ExplodedNode *N) {
1041 while (N) {
1042 std::optional<StmtPoint> SP = N->getLocation().getAs<StmtPoint>();
1043 if (SP) {
1044 const Stmt *S = SP->getStmt();
1045 if (!isContainedByStmt(PM, Term, S))
1046 return S;
1048 N = N->getFirstPred();
1050 return nullptr;
1053 static bool isInLoopBody(const ParentMap &PM, const Stmt *S, const Stmt *Term) {
1054 const Stmt *LoopBody = nullptr;
1055 switch (Term->getStmtClass()) {
1056 case Stmt::CXXForRangeStmtClass: {
1057 const auto *FR = cast<CXXForRangeStmt>(Term);
1058 if (isContainedByStmt(PM, FR->getInc(), S))
1059 return true;
1060 if (isContainedByStmt(PM, FR->getLoopVarStmt(), S))
1061 return true;
1062 LoopBody = FR->getBody();
1063 break;
1065 case Stmt::ForStmtClass: {
1066 const auto *FS = cast<ForStmt>(Term);
1067 if (isContainedByStmt(PM, FS->getInc(), S))
1068 return true;
1069 LoopBody = FS->getBody();
1070 break;
1072 case Stmt::ObjCForCollectionStmtClass: {
1073 const auto *FC = cast<ObjCForCollectionStmt>(Term);
1074 LoopBody = FC->getBody();
1075 break;
1077 case Stmt::WhileStmtClass:
1078 LoopBody = cast<WhileStmt>(Term)->getBody();
1079 break;
1080 default:
1081 return false;
1083 return isContainedByStmt(PM, LoopBody, S);
1086 /// Adds a sanitized control-flow diagnostic edge to a path.
1087 static void addEdgeToPath(PathPieces &path,
1088 PathDiagnosticLocation &PrevLoc,
1089 PathDiagnosticLocation NewLoc) {
1090 if (!NewLoc.isValid())
1091 return;
1093 SourceLocation NewLocL = NewLoc.asLocation();
1094 if (NewLocL.isInvalid())
1095 return;
1097 if (!PrevLoc.isValid() || !PrevLoc.asLocation().isValid()) {
1098 PrevLoc = NewLoc;
1099 return;
1102 // Ignore self-edges, which occur when there are multiple nodes at the same
1103 // statement.
1104 if (NewLoc.asStmt() && NewLoc.asStmt() == PrevLoc.asStmt())
1105 return;
1107 path.push_front(
1108 std::make_shared<PathDiagnosticControlFlowPiece>(NewLoc, PrevLoc));
1109 PrevLoc = NewLoc;
1112 /// A customized wrapper for CFGBlock::getTerminatorCondition()
1113 /// which returns the element for ObjCForCollectionStmts.
1114 static const Stmt *getTerminatorCondition(const CFGBlock *B) {
1115 const Stmt *S = B->getTerminatorCondition();
1116 if (const auto *FS = dyn_cast_or_null<ObjCForCollectionStmt>(S))
1117 return FS->getElement();
1118 return S;
1121 constexpr llvm::StringLiteral StrEnteringLoop = "Entering loop body";
1122 constexpr llvm::StringLiteral StrLoopBodyZero = "Loop body executed 0 times";
1123 constexpr llvm::StringLiteral StrLoopRangeEmpty =
1124 "Loop body skipped when range is empty";
1125 constexpr llvm::StringLiteral StrLoopCollectionEmpty =
1126 "Loop body skipped when collection is empty";
1128 static std::unique_ptr<FilesToLineNumsMap>
1129 findExecutedLines(const SourceManager &SM, const ExplodedNode *N);
1131 void PathDiagnosticBuilder::generatePathDiagnosticsForNode(
1132 PathDiagnosticConstruct &C, PathDiagnosticLocation &PrevLoc) const {
1133 ProgramPoint P = C.getCurrentNode()->getLocation();
1134 const SourceManager &SM = getSourceManager();
1136 // Have we encountered an entrance to a call? It may be
1137 // the case that we have not encountered a matching
1138 // call exit before this point. This means that the path
1139 // terminated within the call itself.
1140 if (auto CE = P.getAs<CallEnter>()) {
1142 if (C.shouldAddPathEdges()) {
1143 // Add an edge to the start of the function.
1144 const StackFrameContext *CalleeLC = CE->getCalleeContext();
1145 const Decl *D = CalleeLC->getDecl();
1146 // Add the edge only when the callee has body. We jump to the beginning
1147 // of the *declaration*, however we expect it to be followed by the
1148 // body. This isn't the case for autosynthesized property accessors in
1149 // Objective-C. No need for a similar extra check for CallExit points
1150 // because the exit edge comes from a statement (i.e. return),
1151 // not from declaration.
1152 if (D->hasBody())
1153 addEdgeToPath(C.getActivePath(), PrevLoc,
1154 PathDiagnosticLocation::createBegin(D, SM));
1157 // Did we visit an entire call?
1158 bool VisitedEntireCall = C.PD->isWithinCall();
1159 C.PD->popActivePath();
1161 PathDiagnosticCallPiece *Call;
1162 if (VisitedEntireCall) {
1163 Call = cast<PathDiagnosticCallPiece>(C.getActivePath().front().get());
1164 } else {
1165 // The path terminated within a nested location context, create a new
1166 // call piece to encapsulate the rest of the path pieces.
1167 const Decl *Caller = CE->getLocationContext()->getDecl();
1168 Call = PathDiagnosticCallPiece::construct(C.getActivePath(), Caller);
1169 assert(C.getActivePath().size() == 1 &&
1170 C.getActivePath().front().get() == Call);
1172 // Since we just transferred the path over to the call piece, reset the
1173 // mapping of the active path to the current location context.
1174 assert(C.isInLocCtxMap(&C.getActivePath()) &&
1175 "When we ascend to a previously unvisited call, the active path's "
1176 "address shouldn't change, but rather should be compacted into "
1177 "a single CallEvent!");
1178 C.updateLocCtxMap(&C.getActivePath(), C.getCurrLocationContext());
1180 // Record the location context mapping for the path within the call.
1181 assert(!C.isInLocCtxMap(&Call->path) &&
1182 "When we ascend to a previously unvisited call, this must be the "
1183 "first time we encounter the caller context!");
1184 C.updateLocCtxMap(&Call->path, CE->getCalleeContext());
1186 Call->setCallee(*CE, SM);
1188 // Update the previous location in the active path.
1189 PrevLoc = Call->getLocation();
1191 if (!C.CallStack.empty()) {
1192 assert(C.CallStack.back().first == Call);
1193 C.CallStack.pop_back();
1195 return;
1198 assert(C.getCurrLocationContext() == C.getLocationContextForActivePath() &&
1199 "The current position in the bug path is out of sync with the "
1200 "location context associated with the active path!");
1202 // Have we encountered an exit from a function call?
1203 if (std::optional<CallExitEnd> CE = P.getAs<CallExitEnd>()) {
1205 // We are descending into a call (backwards). Construct
1206 // a new call piece to contain the path pieces for that call.
1207 auto Call = PathDiagnosticCallPiece::construct(*CE, SM);
1208 // Record the mapping from call piece to LocationContext.
1209 assert(!C.isInLocCtxMap(&Call->path) &&
1210 "We just entered a call, this must've been the first time we "
1211 "encounter its context!");
1212 C.updateLocCtxMap(&Call->path, CE->getCalleeContext());
1214 if (C.shouldAddPathEdges()) {
1215 // Add the edge to the return site.
1216 addEdgeToPath(C.getActivePath(), PrevLoc, Call->callReturn);
1217 PrevLoc.invalidate();
1220 auto *P = Call.get();
1221 C.getActivePath().push_front(std::move(Call));
1223 // Make the contents of the call the active path for now.
1224 C.PD->pushActivePath(&P->path);
1225 C.CallStack.push_back(CallWithEntry(P, C.getCurrentNode()));
1226 return;
1229 if (auto PS = P.getAs<PostStmt>()) {
1230 if (!C.shouldAddPathEdges())
1231 return;
1233 // Add an edge. If this is an ObjCForCollectionStmt do
1234 // not add an edge here as it appears in the CFG both
1235 // as a terminator and as a terminator condition.
1236 if (!isa<ObjCForCollectionStmt>(PS->getStmt())) {
1237 PathDiagnosticLocation L =
1238 PathDiagnosticLocation(PS->getStmt(), SM, C.getCurrLocationContext());
1239 addEdgeToPath(C.getActivePath(), PrevLoc, L);
1242 } else if (auto BE = P.getAs<BlockEdge>()) {
1244 if (C.shouldAddControlNotes()) {
1245 generateMinimalDiagForBlockEdge(C, *BE);
1248 if (!C.shouldAddPathEdges()) {
1249 return;
1252 // Are we jumping to the head of a loop? Add a special diagnostic.
1253 if (const Stmt *Loop = BE->getSrc()->getLoopTarget()) {
1254 PathDiagnosticLocation L(Loop, SM, C.getCurrLocationContext());
1255 const Stmt *Body = nullptr;
1257 if (const auto *FS = dyn_cast<ForStmt>(Loop))
1258 Body = FS->getBody();
1259 else if (const auto *WS = dyn_cast<WhileStmt>(Loop))
1260 Body = WS->getBody();
1261 else if (const auto *OFS = dyn_cast<ObjCForCollectionStmt>(Loop)) {
1262 Body = OFS->getBody();
1263 } else if (const auto *FRS = dyn_cast<CXXForRangeStmt>(Loop)) {
1264 Body = FRS->getBody();
1266 // do-while statements are explicitly excluded here
1268 auto p = std::make_shared<PathDiagnosticEventPiece>(
1269 L, "Looping back to the head of the loop");
1270 p->setPrunable(true);
1272 addEdgeToPath(C.getActivePath(), PrevLoc, p->getLocation());
1273 // We might've added a very similar control node already
1274 if (!C.shouldAddControlNotes()) {
1275 C.getActivePath().push_front(std::move(p));
1278 if (const auto *CS = dyn_cast_or_null<CompoundStmt>(Body)) {
1279 addEdgeToPath(C.getActivePath(), PrevLoc,
1280 PathDiagnosticLocation::createEndBrace(CS, SM));
1284 const CFGBlock *BSrc = BE->getSrc();
1285 const ParentMap &PM = C.getParentMap();
1287 if (const Stmt *Term = BSrc->getTerminatorStmt()) {
1288 // Are we jumping past the loop body without ever executing the
1289 // loop (because the condition was false)?
1290 if (isLoop(Term)) {
1291 const Stmt *TermCond = getTerminatorCondition(BSrc);
1292 bool IsInLoopBody = isInLoopBody(
1293 PM, getStmtBeforeCond(PM, TermCond, C.getCurrentNode()), Term);
1295 StringRef str;
1297 if (isJumpToFalseBranch(&*BE)) {
1298 if (!IsInLoopBody) {
1299 if (isa<ObjCForCollectionStmt>(Term)) {
1300 str = StrLoopCollectionEmpty;
1301 } else if (isa<CXXForRangeStmt>(Term)) {
1302 str = StrLoopRangeEmpty;
1303 } else {
1304 str = StrLoopBodyZero;
1307 } else {
1308 str = StrEnteringLoop;
1311 if (!str.empty()) {
1312 PathDiagnosticLocation L(TermCond ? TermCond : Term, SM,
1313 C.getCurrLocationContext());
1314 auto PE = std::make_shared<PathDiagnosticEventPiece>(L, str);
1315 PE->setPrunable(true);
1316 addEdgeToPath(C.getActivePath(), PrevLoc, PE->getLocation());
1318 // We might've added a very similar control node already
1319 if (!C.shouldAddControlNotes()) {
1320 C.getActivePath().push_front(std::move(PE));
1323 } else if (isa<BreakStmt, ContinueStmt, GotoStmt>(Term)) {
1324 PathDiagnosticLocation L(Term, SM, C.getCurrLocationContext());
1325 addEdgeToPath(C.getActivePath(), PrevLoc, L);
1331 static std::unique_ptr<PathDiagnostic>
1332 generateDiagnosticForBasicReport(const BasicBugReport *R,
1333 const Decl *AnalysisEntryPoint) {
1334 const BugType &BT = R->getBugType();
1335 return std::make_unique<PathDiagnostic>(
1336 BT.getCheckerName(), R->getDeclWithIssue(), BT.getDescription(),
1337 R->getDescription(), R->getShortDescription(/*UseFallback=*/false),
1338 BT.getCategory(), R->getUniqueingLocation(), R->getUniqueingDecl(),
1339 AnalysisEntryPoint, std::make_unique<FilesToLineNumsMap>());
1342 static std::unique_ptr<PathDiagnostic>
1343 generateEmptyDiagnosticForReport(const PathSensitiveBugReport *R,
1344 const SourceManager &SM,
1345 const Decl *AnalysisEntryPoint) {
1346 const BugType &BT = R->getBugType();
1347 return std::make_unique<PathDiagnostic>(
1348 BT.getCheckerName(), R->getDeclWithIssue(), BT.getDescription(),
1349 R->getDescription(), R->getShortDescription(/*UseFallback=*/false),
1350 BT.getCategory(), R->getUniqueingLocation(), R->getUniqueingDecl(),
1351 AnalysisEntryPoint, findExecutedLines(SM, R->getErrorNode()));
1354 static const Stmt *getStmtParent(const Stmt *S, const ParentMap &PM) {
1355 if (!S)
1356 return nullptr;
1358 while (true) {
1359 S = PM.getParentIgnoreParens(S);
1361 if (!S)
1362 break;
1364 if (isa<FullExpr, CXXBindTemporaryExpr, SubstNonTypeTemplateParmExpr>(S))
1365 continue;
1367 break;
1370 return S;
1373 static bool isConditionForTerminator(const Stmt *S, const Stmt *Cond) {
1374 switch (S->getStmtClass()) {
1375 case Stmt::BinaryOperatorClass: {
1376 const auto *BO = cast<BinaryOperator>(S);
1377 if (!BO->isLogicalOp())
1378 return false;
1379 return BO->getLHS() == Cond || BO->getRHS() == Cond;
1381 case Stmt::IfStmtClass:
1382 return cast<IfStmt>(S)->getCond() == Cond;
1383 case Stmt::ForStmtClass:
1384 return cast<ForStmt>(S)->getCond() == Cond;
1385 case Stmt::WhileStmtClass:
1386 return cast<WhileStmt>(S)->getCond() == Cond;
1387 case Stmt::DoStmtClass:
1388 return cast<DoStmt>(S)->getCond() == Cond;
1389 case Stmt::ChooseExprClass:
1390 return cast<ChooseExpr>(S)->getCond() == Cond;
1391 case Stmt::IndirectGotoStmtClass:
1392 return cast<IndirectGotoStmt>(S)->getTarget() == Cond;
1393 case Stmt::SwitchStmtClass:
1394 return cast<SwitchStmt>(S)->getCond() == Cond;
1395 case Stmt::BinaryConditionalOperatorClass:
1396 return cast<BinaryConditionalOperator>(S)->getCond() == Cond;
1397 case Stmt::ConditionalOperatorClass: {
1398 const auto *CO = cast<ConditionalOperator>(S);
1399 return CO->getCond() == Cond ||
1400 CO->getLHS() == Cond ||
1401 CO->getRHS() == Cond;
1403 case Stmt::ObjCForCollectionStmtClass:
1404 return cast<ObjCForCollectionStmt>(S)->getElement() == Cond;
1405 case Stmt::CXXForRangeStmtClass: {
1406 const auto *FRS = cast<CXXForRangeStmt>(S);
1407 return FRS->getCond() == Cond || FRS->getRangeInit() == Cond;
1409 default:
1410 return false;
1414 static bool isIncrementOrInitInForLoop(const Stmt *S, const Stmt *FL) {
1415 if (const auto *FS = dyn_cast<ForStmt>(FL))
1416 return FS->getInc() == S || FS->getInit() == S;
1417 if (const auto *FRS = dyn_cast<CXXForRangeStmt>(FL))
1418 return FRS->getInc() == S || FRS->getRangeStmt() == S ||
1419 FRS->getLoopVarStmt() || FRS->getRangeInit() == S;
1420 return false;
1423 using OptimizedCallsSet = llvm::DenseSet<const PathDiagnosticCallPiece *>;
1425 /// Adds synthetic edges from top-level statements to their subexpressions.
1427 /// This avoids a "swoosh" effect, where an edge from a top-level statement A
1428 /// points to a sub-expression B.1 that's not at the start of B. In these cases,
1429 /// we'd like to see an edge from A to B, then another one from B to B.1.
1430 static void addContextEdges(PathPieces &pieces, const LocationContext *LC) {
1431 const ParentMap &PM = LC->getParentMap();
1432 PathPieces::iterator Prev = pieces.end();
1433 for (PathPieces::iterator I = pieces.begin(), E = Prev; I != E;
1434 Prev = I, ++I) {
1435 auto *Piece = dyn_cast<PathDiagnosticControlFlowPiece>(I->get());
1437 if (!Piece)
1438 continue;
1440 PathDiagnosticLocation SrcLoc = Piece->getStartLocation();
1441 SmallVector<PathDiagnosticLocation, 4> SrcContexts;
1443 PathDiagnosticLocation NextSrcContext = SrcLoc;
1444 const Stmt *InnerStmt = nullptr;
1445 while (NextSrcContext.isValid() && NextSrcContext.asStmt() != InnerStmt) {
1446 SrcContexts.push_back(NextSrcContext);
1447 InnerStmt = NextSrcContext.asStmt();
1448 NextSrcContext = getEnclosingStmtLocation(InnerStmt, LC,
1449 /*allowNested=*/true);
1452 // Repeatedly split the edge as necessary.
1453 // This is important for nested logical expressions (||, &&, ?:) where we
1454 // want to show all the levels of context.
1455 while (true) {
1456 const Stmt *Dst = Piece->getEndLocation().getStmtOrNull();
1458 // We are looking at an edge. Is the destination within a larger
1459 // expression?
1460 PathDiagnosticLocation DstContext =
1461 getEnclosingStmtLocation(Dst, LC, /*allowNested=*/true);
1462 if (!DstContext.isValid() || DstContext.asStmt() == Dst)
1463 break;
1465 // If the source is in the same context, we're already good.
1466 if (llvm::is_contained(SrcContexts, DstContext))
1467 break;
1469 // Update the subexpression node to point to the context edge.
1470 Piece->setStartLocation(DstContext);
1472 // Try to extend the previous edge if it's at the same level as the source
1473 // context.
1474 if (Prev != E) {
1475 auto *PrevPiece = dyn_cast<PathDiagnosticControlFlowPiece>(Prev->get());
1477 if (PrevPiece) {
1478 if (const Stmt *PrevSrc =
1479 PrevPiece->getStartLocation().getStmtOrNull()) {
1480 const Stmt *PrevSrcParent = getStmtParent(PrevSrc, PM);
1481 if (PrevSrcParent ==
1482 getStmtParent(DstContext.getStmtOrNull(), PM)) {
1483 PrevPiece->setEndLocation(DstContext);
1484 break;
1490 // Otherwise, split the current edge into a context edge and a
1491 // subexpression edge. Note that the context statement may itself have
1492 // context.
1493 auto P =
1494 std::make_shared<PathDiagnosticControlFlowPiece>(SrcLoc, DstContext);
1495 Piece = P.get();
1496 I = pieces.insert(I, std::move(P));
1501 /// Move edges from a branch condition to a branch target
1502 /// when the condition is simple.
1504 /// This restructures some of the work of addContextEdges. That function
1505 /// creates edges this may destroy, but they work together to create a more
1506 /// aesthetically set of edges around branches. After the call to
1507 /// addContextEdges, we may have (1) an edge to the branch, (2) an edge from
1508 /// the branch to the branch condition, and (3) an edge from the branch
1509 /// condition to the branch target. We keep (1), but may wish to remove (2)
1510 /// and move the source of (3) to the branch if the branch condition is simple.
1511 static void simplifySimpleBranches(PathPieces &pieces) {
1512 for (PathPieces::iterator I = pieces.begin(), E = pieces.end(); I != E; ++I) {
1513 const auto *PieceI = dyn_cast<PathDiagnosticControlFlowPiece>(I->get());
1515 if (!PieceI)
1516 continue;
1518 const Stmt *s1Start = PieceI->getStartLocation().getStmtOrNull();
1519 const Stmt *s1End = PieceI->getEndLocation().getStmtOrNull();
1521 if (!s1Start || !s1End)
1522 continue;
1524 PathPieces::iterator NextI = I; ++NextI;
1525 if (NextI == E)
1526 break;
1528 PathDiagnosticControlFlowPiece *PieceNextI = nullptr;
1530 while (true) {
1531 if (NextI == E)
1532 break;
1534 const auto *EV = dyn_cast<PathDiagnosticEventPiece>(NextI->get());
1535 if (EV) {
1536 StringRef S = EV->getString();
1537 if (S == StrEnteringLoop || S == StrLoopBodyZero ||
1538 S == StrLoopCollectionEmpty || S == StrLoopRangeEmpty) {
1539 ++NextI;
1540 continue;
1542 break;
1545 PieceNextI = dyn_cast<PathDiagnosticControlFlowPiece>(NextI->get());
1546 break;
1549 if (!PieceNextI)
1550 continue;
1552 const Stmt *s2Start = PieceNextI->getStartLocation().getStmtOrNull();
1553 const Stmt *s2End = PieceNextI->getEndLocation().getStmtOrNull();
1555 if (!s2Start || !s2End || s1End != s2Start)
1556 continue;
1558 // We only perform this transformation for specific branch kinds.
1559 // We don't want to do this for do..while, for example.
1560 if (!isa<ForStmt, WhileStmt, IfStmt, ObjCForCollectionStmt,
1561 CXXForRangeStmt>(s1Start))
1562 continue;
1564 // Is s1End the branch condition?
1565 if (!isConditionForTerminator(s1Start, s1End))
1566 continue;
1568 // Perform the hoisting by eliminating (2) and changing the start
1569 // location of (3).
1570 PieceNextI->setStartLocation(PieceI->getStartLocation());
1571 I = pieces.erase(I);
1575 /// Returns the number of bytes in the given (character-based) SourceRange.
1577 /// If the locations in the range are not on the same line, returns
1578 /// std::nullopt.
1580 /// Note that this does not do a precise user-visible character or column count.
1581 static std::optional<size_t> getLengthOnSingleLine(const SourceManager &SM,
1582 SourceRange Range) {
1583 SourceRange ExpansionRange(SM.getExpansionLoc(Range.getBegin()),
1584 SM.getExpansionRange(Range.getEnd()).getEnd());
1586 FileID FID = SM.getFileID(ExpansionRange.getBegin());
1587 if (FID != SM.getFileID(ExpansionRange.getEnd()))
1588 return std::nullopt;
1590 std::optional<MemoryBufferRef> Buffer = SM.getBufferOrNone(FID);
1591 if (!Buffer)
1592 return std::nullopt;
1594 unsigned BeginOffset = SM.getFileOffset(ExpansionRange.getBegin());
1595 unsigned EndOffset = SM.getFileOffset(ExpansionRange.getEnd());
1596 StringRef Snippet = Buffer->getBuffer().slice(BeginOffset, EndOffset);
1598 // We're searching the raw bytes of the buffer here, which might include
1599 // escaped newlines and such. That's okay; we're trying to decide whether the
1600 // SourceRange is covering a large or small amount of space in the user's
1601 // editor.
1602 if (Snippet.find_first_of("\r\n") != StringRef::npos)
1603 return std::nullopt;
1605 // This isn't Unicode-aware, but it doesn't need to be.
1606 return Snippet.size();
1609 /// \sa getLengthOnSingleLine(SourceManager, SourceRange)
1610 static std::optional<size_t> getLengthOnSingleLine(const SourceManager &SM,
1611 const Stmt *S) {
1612 return getLengthOnSingleLine(SM, S->getSourceRange());
1615 /// Eliminate two-edge cycles created by addContextEdges().
1617 /// Once all the context edges are in place, there are plenty of cases where
1618 /// there's a single edge from a top-level statement to a subexpression,
1619 /// followed by a single path note, and then a reverse edge to get back out to
1620 /// the top level. If the statement is simple enough, the subexpression edges
1621 /// just add noise and make it harder to understand what's going on.
1623 /// This function only removes edges in pairs, because removing only one edge
1624 /// might leave other edges dangling.
1626 /// This will not remove edges in more complicated situations:
1627 /// - if there is more than one "hop" leading to or from a subexpression.
1628 /// - if there is an inlined call between the edges instead of a single event.
1629 /// - if the whole statement is large enough that having subexpression arrows
1630 /// might be helpful.
1631 static void removeContextCycles(PathPieces &Path, const SourceManager &SM) {
1632 for (PathPieces::iterator I = Path.begin(), E = Path.end(); I != E; ) {
1633 // Pattern match the current piece and its successor.
1634 const auto *PieceI = dyn_cast<PathDiagnosticControlFlowPiece>(I->get());
1636 if (!PieceI) {
1637 ++I;
1638 continue;
1641 const Stmt *s1Start = PieceI->getStartLocation().getStmtOrNull();
1642 const Stmt *s1End = PieceI->getEndLocation().getStmtOrNull();
1644 PathPieces::iterator NextI = I; ++NextI;
1645 if (NextI == E)
1646 break;
1648 const auto *PieceNextI =
1649 dyn_cast<PathDiagnosticControlFlowPiece>(NextI->get());
1651 if (!PieceNextI) {
1652 if (isa<PathDiagnosticEventPiece>(NextI->get())) {
1653 ++NextI;
1654 if (NextI == E)
1655 break;
1656 PieceNextI = dyn_cast<PathDiagnosticControlFlowPiece>(NextI->get());
1659 if (!PieceNextI) {
1660 ++I;
1661 continue;
1665 const Stmt *s2Start = PieceNextI->getStartLocation().getStmtOrNull();
1666 const Stmt *s2End = PieceNextI->getEndLocation().getStmtOrNull();
1668 if (s1Start && s2Start && s1Start == s2End && s2Start == s1End) {
1669 const size_t MAX_SHORT_LINE_LENGTH = 80;
1670 std::optional<size_t> s1Length = getLengthOnSingleLine(SM, s1Start);
1671 if (s1Length && *s1Length <= MAX_SHORT_LINE_LENGTH) {
1672 std::optional<size_t> s2Length = getLengthOnSingleLine(SM, s2Start);
1673 if (s2Length && *s2Length <= MAX_SHORT_LINE_LENGTH) {
1674 Path.erase(I);
1675 I = Path.erase(NextI);
1676 continue;
1681 ++I;
1685 /// Return true if X is contained by Y.
1686 static bool lexicalContains(const ParentMap &PM, const Stmt *X, const Stmt *Y) {
1687 while (X) {
1688 if (X == Y)
1689 return true;
1690 X = PM.getParent(X);
1692 return false;
1695 // Remove short edges on the same line less than 3 columns in difference.
1696 static void removePunyEdges(PathPieces &path, const SourceManager &SM,
1697 const ParentMap &PM) {
1698 bool erased = false;
1700 for (PathPieces::iterator I = path.begin(), E = path.end(); I != E;
1701 erased ? I : ++I) {
1702 erased = false;
1704 const auto *PieceI = dyn_cast<PathDiagnosticControlFlowPiece>(I->get());
1706 if (!PieceI)
1707 continue;
1709 const Stmt *start = PieceI->getStartLocation().getStmtOrNull();
1710 const Stmt *end = PieceI->getEndLocation().getStmtOrNull();
1712 if (!start || !end)
1713 continue;
1715 const Stmt *endParent = PM.getParent(end);
1716 if (!endParent)
1717 continue;
1719 if (isConditionForTerminator(end, endParent))
1720 continue;
1722 SourceLocation FirstLoc = start->getBeginLoc();
1723 SourceLocation SecondLoc = end->getBeginLoc();
1725 if (!SM.isWrittenInSameFile(FirstLoc, SecondLoc))
1726 continue;
1727 if (SM.isBeforeInTranslationUnit(SecondLoc, FirstLoc))
1728 std::swap(SecondLoc, FirstLoc);
1730 SourceRange EdgeRange(FirstLoc, SecondLoc);
1731 std::optional<size_t> ByteWidth = getLengthOnSingleLine(SM, EdgeRange);
1733 // If the statements are on different lines, continue.
1734 if (!ByteWidth)
1735 continue;
1737 const size_t MAX_PUNY_EDGE_LENGTH = 2;
1738 if (*ByteWidth <= MAX_PUNY_EDGE_LENGTH) {
1739 // FIXME: There are enough /bytes/ between the endpoints of the edge, but
1740 // there might not be enough /columns/. A proper user-visible column count
1741 // is probably too expensive, though.
1742 I = path.erase(I);
1743 erased = true;
1744 continue;
1749 static void removeIdenticalEvents(PathPieces &path) {
1750 for (PathPieces::iterator I = path.begin(), E = path.end(); I != E; ++I) {
1751 const auto *PieceI = dyn_cast<PathDiagnosticEventPiece>(I->get());
1753 if (!PieceI)
1754 continue;
1756 PathPieces::iterator NextI = I; ++NextI;
1757 if (NextI == E)
1758 return;
1760 const auto *PieceNextI = dyn_cast<PathDiagnosticEventPiece>(NextI->get());
1762 if (!PieceNextI)
1763 continue;
1765 // Erase the second piece if it has the same exact message text.
1766 if (PieceI->getString() == PieceNextI->getString()) {
1767 path.erase(NextI);
1772 static bool optimizeEdges(const PathDiagnosticConstruct &C, PathPieces &path,
1773 OptimizedCallsSet &OCS) {
1774 bool hasChanges = false;
1775 const LocationContext *LC = C.getLocationContextFor(&path);
1776 assert(LC);
1777 const ParentMap &PM = LC->getParentMap();
1778 const SourceManager &SM = C.getSourceManager();
1780 for (PathPieces::iterator I = path.begin(), E = path.end(); I != E; ) {
1781 // Optimize subpaths.
1782 if (auto *CallI = dyn_cast<PathDiagnosticCallPiece>(I->get())) {
1783 // Record the fact that a call has been optimized so we only do the
1784 // effort once.
1785 if (!OCS.count(CallI)) {
1786 while (optimizeEdges(C, CallI->path, OCS)) {
1788 OCS.insert(CallI);
1790 ++I;
1791 continue;
1794 // Pattern match the current piece and its successor.
1795 auto *PieceI = dyn_cast<PathDiagnosticControlFlowPiece>(I->get());
1797 if (!PieceI) {
1798 ++I;
1799 continue;
1802 const Stmt *s1Start = PieceI->getStartLocation().getStmtOrNull();
1803 const Stmt *s1End = PieceI->getEndLocation().getStmtOrNull();
1804 const Stmt *level1 = getStmtParent(s1Start, PM);
1805 const Stmt *level2 = getStmtParent(s1End, PM);
1807 PathPieces::iterator NextI = I; ++NextI;
1808 if (NextI == E)
1809 break;
1811 const auto *PieceNextI = dyn_cast<PathDiagnosticControlFlowPiece>(NextI->get());
1813 if (!PieceNextI) {
1814 ++I;
1815 continue;
1818 const Stmt *s2Start = PieceNextI->getStartLocation().getStmtOrNull();
1819 const Stmt *s2End = PieceNextI->getEndLocation().getStmtOrNull();
1820 const Stmt *level3 = getStmtParent(s2Start, PM);
1821 const Stmt *level4 = getStmtParent(s2End, PM);
1823 // Rule I.
1825 // If we have two consecutive control edges whose end/begin locations
1826 // are at the same level (e.g. statements or top-level expressions within
1827 // a compound statement, or siblings share a single ancestor expression),
1828 // then merge them if they have no interesting intermediate event.
1830 // For example:
1832 // (1.1 -> 1.2) -> (1.2 -> 1.3) becomes (1.1 -> 1.3) because the common
1833 // parent is '1'. Here 'x.y.z' represents the hierarchy of statements.
1835 // NOTE: this will be limited later in cases where we add barriers
1836 // to prevent this optimization.
1837 if (level1 && level1 == level2 && level1 == level3 && level1 == level4) {
1838 PieceI->setEndLocation(PieceNextI->getEndLocation());
1839 path.erase(NextI);
1840 hasChanges = true;
1841 continue;
1844 // Rule II.
1846 // Eliminate edges between subexpressions and parent expressions
1847 // when the subexpression is consumed.
1849 // NOTE: this will be limited later in cases where we add barriers
1850 // to prevent this optimization.
1851 if (s1End && s1End == s2Start && level2) {
1852 bool removeEdge = false;
1853 // Remove edges into the increment or initialization of a
1854 // loop that have no interleaving event. This means that
1855 // they aren't interesting.
1856 if (isIncrementOrInitInForLoop(s1End, level2))
1857 removeEdge = true;
1858 // Next only consider edges that are not anchored on
1859 // the condition of a terminator. This are intermediate edges
1860 // that we might want to trim.
1861 else if (!isConditionForTerminator(level2, s1End)) {
1862 // Trim edges on expressions that are consumed by
1863 // the parent expression.
1864 if (isa<Expr>(s1End) && PM.isConsumedExpr(cast<Expr>(s1End))) {
1865 removeEdge = true;
1867 // Trim edges where a lexical containment doesn't exist.
1868 // For example:
1870 // X -> Y -> Z
1872 // If 'Z' lexically contains Y (it is an ancestor) and
1873 // 'X' does not lexically contain Y (it is a descendant OR
1874 // it has no lexical relationship at all) then trim.
1876 // This can eliminate edges where we dive into a subexpression
1877 // and then pop back out, etc.
1878 else if (s1Start && s2End &&
1879 lexicalContains(PM, s2Start, s2End) &&
1880 !lexicalContains(PM, s1End, s1Start)) {
1881 removeEdge = true;
1883 // Trim edges from a subexpression back to the top level if the
1884 // subexpression is on a different line.
1886 // A.1 -> A -> B
1887 // becomes
1888 // A.1 -> B
1890 // These edges just look ugly and don't usually add anything.
1891 else if (s1Start && s2End &&
1892 lexicalContains(PM, s1Start, s1End)) {
1893 SourceRange EdgeRange(PieceI->getEndLocation().asLocation(),
1894 PieceI->getStartLocation().asLocation());
1895 if (!getLengthOnSingleLine(SM, EdgeRange))
1896 removeEdge = true;
1900 if (removeEdge) {
1901 PieceI->setEndLocation(PieceNextI->getEndLocation());
1902 path.erase(NextI);
1903 hasChanges = true;
1904 continue;
1908 // Optimize edges for ObjC fast-enumeration loops.
1910 // (X -> collection) -> (collection -> element)
1912 // becomes:
1914 // (X -> element)
1915 if (s1End == s2Start) {
1916 const auto *FS = dyn_cast_or_null<ObjCForCollectionStmt>(level3);
1917 if (FS && FS->getCollection()->IgnoreParens() == s2Start &&
1918 s2End == FS->getElement()) {
1919 PieceI->setEndLocation(PieceNextI->getEndLocation());
1920 path.erase(NextI);
1921 hasChanges = true;
1922 continue;
1926 // No changes at this index? Move to the next one.
1927 ++I;
1930 if (!hasChanges) {
1931 // Adjust edges into subexpressions to make them more uniform
1932 // and aesthetically pleasing.
1933 addContextEdges(path, LC);
1934 // Remove "cyclical" edges that include one or more context edges.
1935 removeContextCycles(path, SM);
1936 // Hoist edges originating from branch conditions to branches
1937 // for simple branches.
1938 simplifySimpleBranches(path);
1939 // Remove any puny edges left over after primary optimization pass.
1940 removePunyEdges(path, SM, PM);
1941 // Remove identical events.
1942 removeIdenticalEvents(path);
1945 return hasChanges;
1948 /// Drop the very first edge in a path, which should be a function entry edge.
1950 /// If the first edge is not a function entry edge (say, because the first
1951 /// statement had an invalid source location), this function does nothing.
1952 // FIXME: We should just generate invalid edges anyway and have the optimizer
1953 // deal with them.
1954 static void dropFunctionEntryEdge(const PathDiagnosticConstruct &C,
1955 PathPieces &Path) {
1956 const auto *FirstEdge =
1957 dyn_cast<PathDiagnosticControlFlowPiece>(Path.front().get());
1958 if (!FirstEdge)
1959 return;
1961 const Decl *D = C.getLocationContextFor(&Path)->getDecl();
1962 PathDiagnosticLocation EntryLoc =
1963 PathDiagnosticLocation::createBegin(D, C.getSourceManager());
1964 if (FirstEdge->getStartLocation() != EntryLoc)
1965 return;
1967 Path.pop_front();
1970 /// Populate executes lines with lines containing at least one diagnostics.
1971 static void updateExecutedLinesWithDiagnosticPieces(PathDiagnostic &PD) {
1973 PathPieces path = PD.path.flatten(/*ShouldFlattenMacros=*/true);
1974 FilesToLineNumsMap &ExecutedLines = PD.getExecutedLines();
1976 for (const auto &P : path) {
1977 FullSourceLoc Loc = P->getLocation().asLocation().getExpansionLoc();
1978 FileID FID = Loc.getFileID();
1979 unsigned LineNo = Loc.getLineNumber();
1980 assert(FID.isValid());
1981 ExecutedLines[FID].insert(LineNo);
1985 PathDiagnosticConstruct::PathDiagnosticConstruct(
1986 const PathDiagnosticConsumer *PDC, const ExplodedNode *ErrorNode,
1987 const PathSensitiveBugReport *R, const Decl *AnalysisEntryPoint)
1988 : Consumer(PDC), CurrentNode(ErrorNode),
1989 SM(CurrentNode->getCodeDecl().getASTContext().getSourceManager()),
1990 PD(generateEmptyDiagnosticForReport(R, getSourceManager(),
1991 AnalysisEntryPoint)) {
1992 LCM[&PD->getActivePath()] = ErrorNode->getLocationContext();
1995 PathDiagnosticBuilder::PathDiagnosticBuilder(
1996 BugReporterContext BRC, std::unique_ptr<ExplodedGraph> BugPath,
1997 PathSensitiveBugReport *r, const ExplodedNode *ErrorNode,
1998 std::unique_ptr<VisitorsDiagnosticsTy> VisitorsDiagnostics)
1999 : BugReporterContext(BRC), BugPath(std::move(BugPath)), R(r),
2000 ErrorNode(ErrorNode),
2001 VisitorsDiagnostics(std::move(VisitorsDiagnostics)) {}
2003 std::unique_ptr<PathDiagnostic>
2004 PathDiagnosticBuilder::generate(const PathDiagnosticConsumer *PDC) const {
2005 const Decl *EntryPoint = getBugReporter().getAnalysisEntryPoint();
2006 PathDiagnosticConstruct Construct(PDC, ErrorNode, R, EntryPoint);
2008 const SourceManager &SM = getSourceManager();
2009 const AnalyzerOptions &Opts = getAnalyzerOptions();
2011 if (!PDC->shouldGenerateDiagnostics())
2012 return generateEmptyDiagnosticForReport(R, getSourceManager(), EntryPoint);
2014 // Construct the final (warning) event for the bug report.
2015 auto EndNotes = VisitorsDiagnostics->find(ErrorNode);
2016 PathDiagnosticPieceRef LastPiece;
2017 if (EndNotes != VisitorsDiagnostics->end()) {
2018 assert(!EndNotes->second.empty());
2019 LastPiece = EndNotes->second[0];
2020 } else {
2021 LastPiece = BugReporterVisitor::getDefaultEndPath(*this, ErrorNode,
2022 *getBugReport());
2024 Construct.PD->setEndOfPath(LastPiece);
2026 PathDiagnosticLocation PrevLoc = Construct.PD->getLocation();
2027 // From the error node to the root, ascend the bug path and construct the bug
2028 // report.
2029 while (Construct.ascendToPrevNode()) {
2030 generatePathDiagnosticsForNode(Construct, PrevLoc);
2032 auto VisitorNotes = VisitorsDiagnostics->find(Construct.getCurrentNode());
2033 if (VisitorNotes == VisitorsDiagnostics->end())
2034 continue;
2036 // This is a workaround due to inability to put shared PathDiagnosticPiece
2037 // into a FoldingSet.
2038 std::set<llvm::FoldingSetNodeID> DeduplicationSet;
2040 // Add pieces from custom visitors.
2041 for (const PathDiagnosticPieceRef &Note : VisitorNotes->second) {
2042 llvm::FoldingSetNodeID ID;
2043 Note->Profile(ID);
2044 if (!DeduplicationSet.insert(ID).second)
2045 continue;
2047 if (PDC->shouldAddPathEdges())
2048 addEdgeToPath(Construct.getActivePath(), PrevLoc, Note->getLocation());
2049 updateStackPiecesWithMessage(Note, Construct.CallStack);
2050 Construct.getActivePath().push_front(Note);
2054 if (PDC->shouldAddPathEdges()) {
2055 // Add an edge to the start of the function.
2056 // We'll prune it out later, but it helps make diagnostics more uniform.
2057 const StackFrameContext *CalleeLC =
2058 Construct.getLocationContextForActivePath()->getStackFrame();
2059 const Decl *D = CalleeLC->getDecl();
2060 addEdgeToPath(Construct.getActivePath(), PrevLoc,
2061 PathDiagnosticLocation::createBegin(D, SM));
2065 // Finally, prune the diagnostic path of uninteresting stuff.
2066 if (!Construct.PD->path.empty()) {
2067 if (R->shouldPrunePath() && Opts.ShouldPrunePaths) {
2068 bool stillHasNotes =
2069 removeUnneededCalls(Construct, Construct.getMutablePieces(), R);
2070 assert(stillHasNotes);
2071 (void)stillHasNotes;
2074 // Remove pop-up notes if needed.
2075 if (!Opts.ShouldAddPopUpNotes)
2076 removePopUpNotes(Construct.getMutablePieces());
2078 // Redirect all call pieces to have valid locations.
2079 adjustCallLocations(Construct.getMutablePieces());
2080 removePiecesWithInvalidLocations(Construct.getMutablePieces());
2082 if (PDC->shouldAddPathEdges()) {
2084 // Reduce the number of edges from a very conservative set
2085 // to an aesthetically pleasing subset that conveys the
2086 // necessary information.
2087 OptimizedCallsSet OCS;
2088 while (optimizeEdges(Construct, Construct.getMutablePieces(), OCS)) {
2091 // Drop the very first function-entry edge. It's not really necessary
2092 // for top-level functions.
2093 dropFunctionEntryEdge(Construct, Construct.getMutablePieces());
2096 // Remove messages that are basically the same, and edges that may not
2097 // make sense.
2098 // We have to do this after edge optimization in the Extensive mode.
2099 removeRedundantMsgs(Construct.getMutablePieces());
2100 removeEdgesToDefaultInitializers(Construct.getMutablePieces());
2103 if (Opts.ShouldDisplayMacroExpansions)
2104 CompactMacroExpandedPieces(Construct.getMutablePieces(), SM);
2106 return std::move(Construct.PD);
2109 //===----------------------------------------------------------------------===//
2110 // Methods for BugType and subclasses.
2111 //===----------------------------------------------------------------------===//
2113 void BugType::anchor() {}
2115 //===----------------------------------------------------------------------===//
2116 // Methods for BugReport and subclasses.
2117 //===----------------------------------------------------------------------===//
2119 LLVM_ATTRIBUTE_USED static bool
2120 isDependency(const CheckerRegistryData &Registry, StringRef CheckerName) {
2121 for (const std::pair<StringRef, StringRef> &Pair : Registry.Dependencies) {
2122 if (Pair.second == CheckerName)
2123 return true;
2125 return false;
2128 LLVM_ATTRIBUTE_USED static bool isHidden(const CheckerRegistryData &Registry,
2129 StringRef CheckerName) {
2130 for (const CheckerInfo &Checker : Registry.Checkers) {
2131 if (Checker.FullName == CheckerName)
2132 return Checker.IsHidden;
2134 llvm_unreachable(
2135 "Checker name not found in CheckerRegistry -- did you retrieve it "
2136 "correctly from CheckerManager::getCurrentCheckerName?");
2139 PathSensitiveBugReport::PathSensitiveBugReport(
2140 const BugType &bt, StringRef shortDesc, StringRef desc,
2141 const ExplodedNode *errorNode, PathDiagnosticLocation LocationToUnique,
2142 const Decl *DeclToUnique)
2143 : BugReport(Kind::PathSensitive, bt, shortDesc, desc), ErrorNode(errorNode),
2144 ErrorNodeRange(getStmt() ? getStmt()->getSourceRange() : SourceRange()),
2145 UniqueingLocation(LocationToUnique), UniqueingDecl(DeclToUnique) {
2146 assert(!isDependency(ErrorNode->getState()
2147 ->getAnalysisManager()
2148 .getCheckerManager()
2149 ->getCheckerRegistryData(),
2150 bt.getCheckerName()) &&
2151 "Some checkers depend on this one! We don't allow dependency "
2152 "checkers to emit warnings, because checkers should depend on "
2153 "*modeling*, not *diagnostics*.");
2155 assert((bt.getCheckerName().starts_with("debug") ||
2156 !isHidden(ErrorNode->getState()
2157 ->getAnalysisManager()
2158 .getCheckerManager()
2159 ->getCheckerRegistryData(),
2160 bt.getCheckerName())) &&
2161 "Hidden checkers musn't emit diagnostics as they are by definition "
2162 "non-user facing!");
2165 void PathSensitiveBugReport::addVisitor(
2166 std::unique_ptr<BugReporterVisitor> visitor) {
2167 if (!visitor)
2168 return;
2170 llvm::FoldingSetNodeID ID;
2171 visitor->Profile(ID);
2173 void *InsertPos = nullptr;
2174 if (CallbacksSet.FindNodeOrInsertPos(ID, InsertPos)) {
2175 return;
2178 Callbacks.push_back(std::move(visitor));
2181 void PathSensitiveBugReport::clearVisitors() {
2182 Callbacks.clear();
2185 const Decl *PathSensitiveBugReport::getDeclWithIssue() const {
2186 const ExplodedNode *N = getErrorNode();
2187 if (!N)
2188 return nullptr;
2190 const LocationContext *LC = N->getLocationContext();
2191 return LC->getStackFrame()->getDecl();
2194 void BasicBugReport::Profile(llvm::FoldingSetNodeID& hash) const {
2195 hash.AddInteger(static_cast<int>(getKind()));
2196 hash.AddPointer(&BT);
2197 hash.AddString(getShortDescription());
2198 assert(Location.isValid());
2199 Location.Profile(hash);
2201 for (SourceRange range : Ranges) {
2202 if (!range.isValid())
2203 continue;
2204 hash.Add(range.getBegin());
2205 hash.Add(range.getEnd());
2209 void PathSensitiveBugReport::Profile(llvm::FoldingSetNodeID &hash) const {
2210 hash.AddInteger(static_cast<int>(getKind()));
2211 hash.AddPointer(&BT);
2212 hash.AddString(getShortDescription());
2213 PathDiagnosticLocation UL = getUniqueingLocation();
2214 if (UL.isValid()) {
2215 UL.Profile(hash);
2216 } else {
2217 // TODO: The statement may be null if the report was emitted before any
2218 // statements were executed. In particular, some checkers by design
2219 // occasionally emit their reports in empty functions (that have no
2220 // statements in their body). Do we profile correctly in this case?
2221 hash.AddPointer(ErrorNode->getCurrentOrPreviousStmtForDiagnostics());
2224 for (SourceRange range : Ranges) {
2225 if (!range.isValid())
2226 continue;
2227 hash.Add(range.getBegin());
2228 hash.Add(range.getEnd());
2232 template <class T>
2233 static void insertToInterestingnessMap(
2234 llvm::DenseMap<T, bugreporter::TrackingKind> &InterestingnessMap, T Val,
2235 bugreporter::TrackingKind TKind) {
2236 auto Result = InterestingnessMap.insert({Val, TKind});
2238 if (Result.second)
2239 return;
2241 // Even if this symbol/region was already marked as interesting as a
2242 // condition, if we later mark it as interesting again but with
2243 // thorough tracking, overwrite it. Entities marked with thorough
2244 // interestiness are the most important (or most interesting, if you will),
2245 // and we wouldn't like to downplay their importance.
2247 switch (TKind) {
2248 case bugreporter::TrackingKind::Thorough:
2249 Result.first->getSecond() = bugreporter::TrackingKind::Thorough;
2250 return;
2251 case bugreporter::TrackingKind::Condition:
2252 return;
2255 llvm_unreachable(
2256 "BugReport::markInteresting currently can only handle 2 different "
2257 "tracking kinds! Please define what tracking kind should this entitiy"
2258 "have, if it was already marked as interesting with a different kind!");
2261 void PathSensitiveBugReport::markInteresting(SymbolRef sym,
2262 bugreporter::TrackingKind TKind) {
2263 if (!sym)
2264 return;
2266 insertToInterestingnessMap(InterestingSymbols, sym, TKind);
2268 // FIXME: No tests exist for this code and it is questionable:
2269 // How to handle multiple metadata for the same region?
2270 if (const auto *meta = dyn_cast<SymbolMetadata>(sym))
2271 markInteresting(meta->getRegion(), TKind);
2274 void PathSensitiveBugReport::markNotInteresting(SymbolRef sym) {
2275 if (!sym)
2276 return;
2277 InterestingSymbols.erase(sym);
2279 // The metadata part of markInteresting is not reversed here.
2280 // Just making the same region not interesting is incorrect
2281 // in specific cases.
2282 if (const auto *meta = dyn_cast<SymbolMetadata>(sym))
2283 markNotInteresting(meta->getRegion());
2286 void PathSensitiveBugReport::markInteresting(const MemRegion *R,
2287 bugreporter::TrackingKind TKind) {
2288 if (!R)
2289 return;
2291 R = R->getBaseRegion();
2292 insertToInterestingnessMap(InterestingRegions, R, TKind);
2294 if (const auto *SR = dyn_cast<SymbolicRegion>(R))
2295 markInteresting(SR->getSymbol(), TKind);
2298 void PathSensitiveBugReport::markNotInteresting(const MemRegion *R) {
2299 if (!R)
2300 return;
2302 R = R->getBaseRegion();
2303 InterestingRegions.erase(R);
2305 if (const auto *SR = dyn_cast<SymbolicRegion>(R))
2306 markNotInteresting(SR->getSymbol());
2309 void PathSensitiveBugReport::markInteresting(SVal V,
2310 bugreporter::TrackingKind TKind) {
2311 markInteresting(V.getAsRegion(), TKind);
2312 markInteresting(V.getAsSymbol(), TKind);
2315 void PathSensitiveBugReport::markInteresting(const LocationContext *LC) {
2316 if (!LC)
2317 return;
2318 InterestingLocationContexts.insert(LC);
2321 std::optional<bugreporter::TrackingKind>
2322 PathSensitiveBugReport::getInterestingnessKind(SVal V) const {
2323 auto RKind = getInterestingnessKind(V.getAsRegion());
2324 auto SKind = getInterestingnessKind(V.getAsSymbol());
2325 if (!RKind)
2326 return SKind;
2327 if (!SKind)
2328 return RKind;
2330 // If either is marked with throrough tracking, return that, we wouldn't like
2331 // to downplay a note's importance by 'only' mentioning it as a condition.
2332 switch(*RKind) {
2333 case bugreporter::TrackingKind::Thorough:
2334 return RKind;
2335 case bugreporter::TrackingKind::Condition:
2336 return SKind;
2339 llvm_unreachable(
2340 "BugReport::getInterestingnessKind currently can only handle 2 different "
2341 "tracking kinds! Please define what tracking kind should we return here "
2342 "when the kind of getAsRegion() and getAsSymbol() is different!");
2343 return std::nullopt;
2346 std::optional<bugreporter::TrackingKind>
2347 PathSensitiveBugReport::getInterestingnessKind(SymbolRef sym) const {
2348 if (!sym)
2349 return std::nullopt;
2350 // We don't currently consider metadata symbols to be interesting
2351 // even if we know their region is interesting. Is that correct behavior?
2352 auto It = InterestingSymbols.find(sym);
2353 if (It == InterestingSymbols.end())
2354 return std::nullopt;
2355 return It->getSecond();
2358 std::optional<bugreporter::TrackingKind>
2359 PathSensitiveBugReport::getInterestingnessKind(const MemRegion *R) const {
2360 if (!R)
2361 return std::nullopt;
2363 R = R->getBaseRegion();
2364 auto It = InterestingRegions.find(R);
2365 if (It != InterestingRegions.end())
2366 return It->getSecond();
2368 if (const auto *SR = dyn_cast<SymbolicRegion>(R))
2369 return getInterestingnessKind(SR->getSymbol());
2370 return std::nullopt;
2373 bool PathSensitiveBugReport::isInteresting(SVal V) const {
2374 return getInterestingnessKind(V).has_value();
2377 bool PathSensitiveBugReport::isInteresting(SymbolRef sym) const {
2378 return getInterestingnessKind(sym).has_value();
2381 bool PathSensitiveBugReport::isInteresting(const MemRegion *R) const {
2382 return getInterestingnessKind(R).has_value();
2385 bool PathSensitiveBugReport::isInteresting(const LocationContext *LC) const {
2386 if (!LC)
2387 return false;
2388 return InterestingLocationContexts.count(LC);
2391 const Stmt *PathSensitiveBugReport::getStmt() const {
2392 if (!ErrorNode)
2393 return nullptr;
2395 ProgramPoint ProgP = ErrorNode->getLocation();
2396 const Stmt *S = nullptr;
2398 if (std::optional<BlockEntrance> BE = ProgP.getAs<BlockEntrance>()) {
2399 CFGBlock &Exit = ProgP.getLocationContext()->getCFG()->getExit();
2400 if (BE->getBlock() == &Exit)
2401 S = ErrorNode->getPreviousStmtForDiagnostics();
2403 if (!S)
2404 S = ErrorNode->getStmtForDiagnostics();
2406 return S;
2409 ArrayRef<SourceRange>
2410 PathSensitiveBugReport::getRanges() const {
2411 // If no custom ranges, add the range of the statement corresponding to
2412 // the error node.
2413 if (Ranges.empty() && isa_and_nonnull<Expr>(getStmt()))
2414 return ErrorNodeRange;
2416 return Ranges;
2419 static bool exitingDestructor(const ExplodedNode *N) {
2420 // Need to loop here, as some times the Error node is already outside of the
2421 // destructor context, and the previous node is an edge that is also outside.
2422 while (N && !N->getLocation().getAs<StmtPoint>()) {
2423 N = N->getFirstPred();
2425 return N && isa<CXXDestructorDecl>(N->getLocationContext()->getDecl());
2428 static const Stmt *
2429 findReasonableStmtCloseToFunctionExit(const ExplodedNode *N) {
2430 if (exitingDestructor(N)) {
2431 // If we are exiting a destructor call, it is more useful to point to
2432 // the next stmt which is usually the temporary declaration.
2433 if (const Stmt *S = N->getNextStmtForDiagnostics())
2434 return S;
2435 // If next stmt is not found, it is likely the end of a top-level
2436 // function analysis. find the last execution statement then.
2438 return N->getPreviousStmtForDiagnostics();
2441 PathDiagnosticLocation
2442 PathSensitiveBugReport::getLocation() const {
2443 assert(ErrorNode && "Cannot create a location with a null node.");
2444 const Stmt *S = ErrorNode->getStmtForDiagnostics();
2445 ProgramPoint P = ErrorNode->getLocation();
2446 const LocationContext *LC = P.getLocationContext();
2447 SourceManager &SM =
2448 ErrorNode->getState()->getStateManager().getContext().getSourceManager();
2450 if (!S) {
2451 // If this is an implicit call, return the implicit call point location.
2452 if (std::optional<PreImplicitCall> PIE = P.getAs<PreImplicitCall>())
2453 return PathDiagnosticLocation(PIE->getLocation(), SM);
2454 if (auto FE = P.getAs<FunctionExitPoint>()) {
2455 if (const ReturnStmt *RS = FE->getStmt())
2456 return PathDiagnosticLocation::createBegin(RS, SM, LC);
2458 S = findReasonableStmtCloseToFunctionExit(ErrorNode);
2460 if (!S)
2461 S = ErrorNode->getNextStmtForDiagnostics();
2464 if (S) {
2465 // Attributed statements usually have corrupted begin locations,
2466 // it's OK to ignore attributes for our purposes and deal with
2467 // the actual annotated statement.
2468 if (const auto *AS = dyn_cast<AttributedStmt>(S))
2469 S = AS->getSubStmt();
2471 // For member expressions, return the location of the '.' or '->'.
2472 if (const auto *ME = dyn_cast<MemberExpr>(S))
2473 return PathDiagnosticLocation::createMemberLoc(ME, SM);
2475 // For binary operators, return the location of the operator.
2476 if (const auto *B = dyn_cast<BinaryOperator>(S))
2477 return PathDiagnosticLocation::createOperatorLoc(B, SM);
2479 if (P.getAs<PostStmtPurgeDeadSymbols>())
2480 return PathDiagnosticLocation::createEnd(S, SM, LC);
2482 if (S->getBeginLoc().isValid())
2483 return PathDiagnosticLocation(S, SM, LC);
2485 return PathDiagnosticLocation(
2486 PathDiagnosticLocation::getValidSourceLocation(S, LC), SM);
2489 return PathDiagnosticLocation::createDeclEnd(ErrorNode->getLocationContext(),
2490 SM);
2493 //===----------------------------------------------------------------------===//
2494 // Methods for BugReporter and subclasses.
2495 //===----------------------------------------------------------------------===//
2497 const ExplodedGraph &PathSensitiveBugReporter::getGraph() const {
2498 return Eng.getGraph();
2501 ProgramStateManager &PathSensitiveBugReporter::getStateManager() const {
2502 return Eng.getStateManager();
2505 BugReporter::BugReporter(BugReporterData &D)
2506 : D(D), UserSuppressions(D.getASTContext()) {}
2508 BugReporter::~BugReporter() {
2509 // Make sure reports are flushed.
2510 assert(StrBugTypes.empty() &&
2511 "Destroying BugReporter before diagnostics are emitted!");
2513 // Free the bug reports we are tracking.
2514 for (const auto I : EQClassesVector)
2515 delete I;
2518 void BugReporter::FlushReports() {
2519 // We need to flush reports in deterministic order to ensure the order
2520 // of the reports is consistent between runs.
2521 for (const auto EQ : EQClassesVector)
2522 FlushReport(*EQ);
2524 // BugReporter owns and deletes only BugTypes created implicitly through
2525 // EmitBasicReport.
2526 // FIXME: There are leaks from checkers that assume that the BugTypes they
2527 // create will be destroyed by the BugReporter.
2528 StrBugTypes.clear();
2531 //===----------------------------------------------------------------------===//
2532 // PathDiagnostics generation.
2533 //===----------------------------------------------------------------------===//
2535 namespace {
2537 /// A wrapper around an ExplodedGraph that contains a single path from the root
2538 /// to the error node.
2539 class BugPathInfo {
2540 public:
2541 std::unique_ptr<ExplodedGraph> BugPath;
2542 PathSensitiveBugReport *Report;
2543 const ExplodedNode *ErrorNode;
2546 /// A wrapper around an ExplodedGraph whose leafs are all error nodes. Can
2547 /// conveniently retrieve bug paths from a single error node to the root.
2548 class BugPathGetter {
2549 std::unique_ptr<ExplodedGraph> TrimmedGraph;
2551 using PriorityMapTy = llvm::DenseMap<const ExplodedNode *, unsigned>;
2553 /// Assign each node with its distance from the root.
2554 PriorityMapTy PriorityMap;
2556 /// Since the getErrorNode() or BugReport refers to the original ExplodedGraph,
2557 /// we need to pair it to the error node of the constructed trimmed graph.
2558 using ReportNewNodePair =
2559 std::pair<PathSensitiveBugReport *, const ExplodedNode *>;
2560 SmallVector<ReportNewNodePair, 32> ReportNodes;
2562 BugPathInfo CurrentBugPath;
2564 /// A helper class for sorting ExplodedNodes by priority.
2565 template <bool Descending>
2566 class PriorityCompare {
2567 const PriorityMapTy &PriorityMap;
2569 public:
2570 PriorityCompare(const PriorityMapTy &M) : PriorityMap(M) {}
2572 bool operator()(const ExplodedNode *LHS, const ExplodedNode *RHS) const {
2573 PriorityMapTy::const_iterator LI = PriorityMap.find(LHS);
2574 PriorityMapTy::const_iterator RI = PriorityMap.find(RHS);
2575 PriorityMapTy::const_iterator E = PriorityMap.end();
2577 if (LI == E)
2578 return Descending;
2579 if (RI == E)
2580 return !Descending;
2582 return Descending ? LI->second > RI->second
2583 : LI->second < RI->second;
2586 bool operator()(const ReportNewNodePair &LHS,
2587 const ReportNewNodePair &RHS) const {
2588 return (*this)(LHS.second, RHS.second);
2592 public:
2593 BugPathGetter(const ExplodedGraph *OriginalGraph,
2594 ArrayRef<PathSensitiveBugReport *> &bugReports);
2596 BugPathInfo *getNextBugPath();
2599 } // namespace
2601 BugPathGetter::BugPathGetter(const ExplodedGraph *OriginalGraph,
2602 ArrayRef<PathSensitiveBugReport *> &bugReports) {
2603 SmallVector<const ExplodedNode *, 32> Nodes;
2604 for (const auto I : bugReports) {
2605 assert(I->isValid() &&
2606 "We only allow BugReporterVisitors and BugReporter itself to "
2607 "invalidate reports!");
2608 Nodes.emplace_back(I->getErrorNode());
2611 // The trimmed graph is created in the body of the constructor to ensure
2612 // that the DenseMaps have been initialized already.
2613 InterExplodedGraphMap ForwardMap;
2614 TrimmedGraph = OriginalGraph->trim(Nodes, &ForwardMap);
2616 // Find the (first) error node in the trimmed graph. We just need to consult
2617 // the node map which maps from nodes in the original graph to nodes
2618 // in the new graph.
2619 llvm::SmallPtrSet<const ExplodedNode *, 32> RemainingNodes;
2621 for (PathSensitiveBugReport *Report : bugReports) {
2622 const ExplodedNode *NewNode = ForwardMap.lookup(Report->getErrorNode());
2623 assert(NewNode &&
2624 "Failed to construct a trimmed graph that contains this error "
2625 "node!");
2626 ReportNodes.emplace_back(Report, NewNode);
2627 RemainingNodes.insert(NewNode);
2630 assert(!RemainingNodes.empty() && "No error node found in the trimmed graph");
2632 // Perform a forward BFS to find all the shortest paths.
2633 std::queue<const ExplodedNode *> WS;
2635 assert(TrimmedGraph->num_roots() == 1);
2636 WS.push(*TrimmedGraph->roots_begin());
2637 unsigned Priority = 0;
2639 while (!WS.empty()) {
2640 const ExplodedNode *Node = WS.front();
2641 WS.pop();
2643 PriorityMapTy::iterator PriorityEntry;
2644 bool IsNew;
2645 std::tie(PriorityEntry, IsNew) = PriorityMap.insert({Node, Priority});
2646 ++Priority;
2648 if (!IsNew) {
2649 assert(PriorityEntry->second <= Priority);
2650 continue;
2653 if (RemainingNodes.erase(Node))
2654 if (RemainingNodes.empty())
2655 break;
2657 for (const ExplodedNode *Succ : Node->succs())
2658 WS.push(Succ);
2661 // Sort the error paths from longest to shortest.
2662 llvm::sort(ReportNodes, PriorityCompare<true>(PriorityMap));
2665 BugPathInfo *BugPathGetter::getNextBugPath() {
2666 if (ReportNodes.empty())
2667 return nullptr;
2669 const ExplodedNode *OrigN;
2670 std::tie(CurrentBugPath.Report, OrigN) = ReportNodes.pop_back_val();
2671 assert(PriorityMap.contains(OrigN) && "error node not accessible from root");
2673 // Create a new graph with a single path. This is the graph that will be
2674 // returned to the caller.
2675 auto GNew = std::make_unique<ExplodedGraph>();
2677 // Now walk from the error node up the BFS path, always taking the
2678 // predeccessor with the lowest number.
2679 ExplodedNode *Succ = nullptr;
2680 while (true) {
2681 // Create the equivalent node in the new graph with the same state
2682 // and location.
2683 ExplodedNode *NewN = GNew->createUncachedNode(
2684 OrigN->getLocation(), OrigN->getState(),
2685 OrigN->getID(), OrigN->isSink());
2687 // Link up the new node with the previous node.
2688 if (Succ)
2689 Succ->addPredecessor(NewN, *GNew);
2690 else
2691 CurrentBugPath.ErrorNode = NewN;
2693 Succ = NewN;
2695 // Are we at the final node?
2696 if (OrigN->pred_empty()) {
2697 GNew->addRoot(NewN);
2698 break;
2701 // Find the next predeccessor node. We choose the node that is marked
2702 // with the lowest BFS number.
2703 OrigN = *std::min_element(OrigN->pred_begin(), OrigN->pred_end(),
2704 PriorityCompare<false>(PriorityMap));
2707 CurrentBugPath.BugPath = std::move(GNew);
2709 return &CurrentBugPath;
2712 /// CompactMacroExpandedPieces - This function postprocesses a PathDiagnostic
2713 /// object and collapses PathDiagosticPieces that are expanded by macros.
2714 static void CompactMacroExpandedPieces(PathPieces &path,
2715 const SourceManager& SM) {
2716 using MacroStackTy = std::vector<
2717 std::pair<std::shared_ptr<PathDiagnosticMacroPiece>, SourceLocation>>;
2719 using PiecesTy = std::vector<PathDiagnosticPieceRef>;
2721 MacroStackTy MacroStack;
2722 PiecesTy Pieces;
2724 for (PathPieces::const_iterator I = path.begin(), E = path.end();
2725 I != E; ++I) {
2726 const auto &piece = *I;
2728 // Recursively compact calls.
2729 if (auto *call = dyn_cast<PathDiagnosticCallPiece>(&*piece)) {
2730 CompactMacroExpandedPieces(call->path, SM);
2733 // Get the location of the PathDiagnosticPiece.
2734 const FullSourceLoc Loc = piece->getLocation().asLocation();
2736 // Determine the instantiation location, which is the location we group
2737 // related PathDiagnosticPieces.
2738 SourceLocation InstantiationLoc = Loc.isMacroID() ?
2739 SM.getExpansionLoc(Loc) :
2740 SourceLocation();
2742 if (Loc.isFileID()) {
2743 MacroStack.clear();
2744 Pieces.push_back(piece);
2745 continue;
2748 assert(Loc.isMacroID());
2750 // Is the PathDiagnosticPiece within the same macro group?
2751 if (!MacroStack.empty() && InstantiationLoc == MacroStack.back().second) {
2752 MacroStack.back().first->subPieces.push_back(piece);
2753 continue;
2756 // We aren't in the same group. Are we descending into a new macro
2757 // or are part of an old one?
2758 std::shared_ptr<PathDiagnosticMacroPiece> MacroGroup;
2760 SourceLocation ParentInstantiationLoc = InstantiationLoc.isMacroID() ?
2761 SM.getExpansionLoc(Loc) :
2762 SourceLocation();
2764 // Walk the entire macro stack.
2765 while (!MacroStack.empty()) {
2766 if (InstantiationLoc == MacroStack.back().second) {
2767 MacroGroup = MacroStack.back().first;
2768 break;
2771 if (ParentInstantiationLoc == MacroStack.back().second) {
2772 MacroGroup = MacroStack.back().first;
2773 break;
2776 MacroStack.pop_back();
2779 if (!MacroGroup || ParentInstantiationLoc == MacroStack.back().second) {
2780 // Create a new macro group and add it to the stack.
2781 auto NewGroup = std::make_shared<PathDiagnosticMacroPiece>(
2782 PathDiagnosticLocation::createSingleLocation(piece->getLocation()));
2784 if (MacroGroup)
2785 MacroGroup->subPieces.push_back(NewGroup);
2786 else {
2787 assert(InstantiationLoc.isFileID());
2788 Pieces.push_back(NewGroup);
2791 MacroGroup = NewGroup;
2792 MacroStack.push_back(std::make_pair(MacroGroup, InstantiationLoc));
2795 // Finally, add the PathDiagnosticPiece to the group.
2796 MacroGroup->subPieces.push_back(piece);
2799 // Now take the pieces and construct a new PathDiagnostic.
2800 path.clear();
2802 path.insert(path.end(), Pieces.begin(), Pieces.end());
2805 /// Generate notes from all visitors.
2806 /// Notes associated with @c ErrorNode are generated using
2807 /// @c getEndPath, and the rest are generated with @c VisitNode.
2808 static std::unique_ptr<VisitorsDiagnosticsTy>
2809 generateVisitorsDiagnostics(PathSensitiveBugReport *R,
2810 const ExplodedNode *ErrorNode,
2811 BugReporterContext &BRC) {
2812 std::unique_ptr<VisitorsDiagnosticsTy> Notes =
2813 std::make_unique<VisitorsDiagnosticsTy>();
2814 PathSensitiveBugReport::VisitorList visitors;
2816 // Run visitors on all nodes starting from the node *before* the last one.
2817 // The last node is reserved for notes generated with @c getEndPath.
2818 const ExplodedNode *NextNode = ErrorNode->getFirstPred();
2819 while (NextNode) {
2821 // At each iteration, move all visitors from report to visitor list. This is
2822 // important, because the Profile() functions of the visitors make sure that
2823 // a visitor isn't added multiple times for the same node, but it's fine
2824 // to add the a visitor with Profile() for different nodes (e.g. tracking
2825 // a region at different points of the symbolic execution).
2826 for (std::unique_ptr<BugReporterVisitor> &Visitor : R->visitors())
2827 visitors.push_back(std::move(Visitor));
2829 R->clearVisitors();
2831 const ExplodedNode *Pred = NextNode->getFirstPred();
2832 if (!Pred) {
2833 PathDiagnosticPieceRef LastPiece;
2834 for (auto &V : visitors) {
2835 V->finalizeVisitor(BRC, ErrorNode, *R);
2837 if (auto Piece = V->getEndPath(BRC, ErrorNode, *R)) {
2838 assert(!LastPiece &&
2839 "There can only be one final piece in a diagnostic.");
2840 assert(Piece->getKind() == PathDiagnosticPiece::Kind::Event &&
2841 "The final piece must contain a message!");
2842 LastPiece = std::move(Piece);
2843 (*Notes)[ErrorNode].push_back(LastPiece);
2846 break;
2849 for (auto &V : visitors) {
2850 auto P = V->VisitNode(NextNode, BRC, *R);
2851 if (P)
2852 (*Notes)[NextNode].push_back(std::move(P));
2855 if (!R->isValid())
2856 break;
2858 NextNode = Pred;
2861 return Notes;
2864 std::optional<PathDiagnosticBuilder> PathDiagnosticBuilder::findValidReport(
2865 ArrayRef<PathSensitiveBugReport *> &bugReports,
2866 PathSensitiveBugReporter &Reporter) {
2867 Z3CrosscheckOracle Z3Oracle(Reporter.getAnalyzerOptions());
2869 BugPathGetter BugGraph(&Reporter.getGraph(), bugReports);
2871 while (BugPathInfo *BugPath = BugGraph.getNextBugPath()) {
2872 // Find the BugReport with the original location.
2873 PathSensitiveBugReport *R = BugPath->Report;
2874 assert(R && "No original report found for sliced graph.");
2875 assert(R->isValid() && "Report selected by trimmed graph marked invalid.");
2876 const ExplodedNode *ErrorNode = BugPath->ErrorNode;
2878 // Register refutation visitors first, if they mark the bug invalid no
2879 // further analysis is required
2880 R->addVisitor<LikelyFalsePositiveSuppressionBRVisitor>();
2882 // Register additional node visitors.
2883 R->addVisitor<NilReceiverBRVisitor>();
2884 R->addVisitor<ConditionBRVisitor>();
2885 R->addVisitor<TagVisitor>();
2887 BugReporterContext BRC(Reporter);
2889 // Run all visitors on a given graph, once.
2890 std::unique_ptr<VisitorsDiagnosticsTy> visitorNotes =
2891 generateVisitorsDiagnostics(R, ErrorNode, BRC);
2893 if (R->isValid()) {
2894 if (Reporter.getAnalyzerOptions().ShouldCrosscheckWithZ3) {
2895 // If crosscheck is enabled, remove all visitors, add the refutation
2896 // visitor and check again
2897 R->clearVisitors();
2898 Z3CrosscheckVisitor::Z3Result CrosscheckResult;
2899 R->addVisitor<Z3CrosscheckVisitor>(CrosscheckResult,
2900 Reporter.getAnalyzerOptions());
2902 // We don't overwrite the notes inserted by other visitors because the
2903 // refutation manager does not add any new note to the path
2904 generateVisitorsDiagnostics(R, BugPath->ErrorNode, BRC);
2905 switch (Z3Oracle.interpretQueryResult(CrosscheckResult)) {
2906 case Z3CrosscheckOracle::RejectReport:
2907 ++NumTimesReportRefuted;
2908 R->markInvalid("Infeasible constraints", /*Data=*/nullptr);
2909 continue;
2910 case Z3CrosscheckOracle::RejectEQClass:
2911 ++NumTimesReportEQClassAborted;
2912 return {};
2913 case Z3CrosscheckOracle::AcceptReport:
2914 ++NumTimesReportPassesZ3;
2915 break;
2919 assert(R->isValid());
2920 return PathDiagnosticBuilder(std::move(BRC), std::move(BugPath->BugPath),
2921 BugPath->Report, BugPath->ErrorNode,
2922 std::move(visitorNotes));
2926 ++NumTimesReportEQClassWasExhausted;
2927 return {};
2930 std::unique_ptr<DiagnosticForConsumerMapTy>
2931 PathSensitiveBugReporter::generatePathDiagnostics(
2932 ArrayRef<PathDiagnosticConsumer *> consumers,
2933 ArrayRef<PathSensitiveBugReport *> &bugReports) {
2934 assert(!bugReports.empty());
2936 auto Out = std::make_unique<DiagnosticForConsumerMapTy>();
2938 std::optional<PathDiagnosticBuilder> PDB =
2939 PathDiagnosticBuilder::findValidReport(bugReports, *this);
2941 if (PDB) {
2942 for (PathDiagnosticConsumer *PC : consumers) {
2943 if (std::unique_ptr<PathDiagnostic> PD = PDB->generate(PC)) {
2944 (*Out)[PC] = std::move(PD);
2949 return Out;
2952 void BugReporter::emitReport(std::unique_ptr<BugReport> R) {
2953 bool ValidSourceLoc = R->getLocation().isValid();
2954 assert(ValidSourceLoc);
2955 // If we mess up in a release build, we'd still prefer to just drop the bug
2956 // instead of trying to go on.
2957 if (!ValidSourceLoc)
2958 return;
2960 // If the user asked to suppress this report, we should skip it.
2961 if (UserSuppressions.isSuppressed(*R))
2962 return;
2964 // Compute the bug report's hash to determine its equivalence class.
2965 llvm::FoldingSetNodeID ID;
2966 R->Profile(ID);
2968 // Lookup the equivance class. If there isn't one, create it.
2969 void *InsertPos;
2970 BugReportEquivClass* EQ = EQClasses.FindNodeOrInsertPos(ID, InsertPos);
2972 if (!EQ) {
2973 EQ = new BugReportEquivClass(std::move(R));
2974 EQClasses.InsertNode(EQ, InsertPos);
2975 EQClassesVector.push_back(EQ);
2976 } else
2977 EQ->AddReport(std::move(R));
2980 void PathSensitiveBugReporter::emitReport(std::unique_ptr<BugReport> R) {
2981 if (auto PR = dyn_cast<PathSensitiveBugReport>(R.get()))
2982 if (const ExplodedNode *E = PR->getErrorNode()) {
2983 // An error node must either be a sink or have a tag, otherwise
2984 // it could get reclaimed before the path diagnostic is created.
2985 assert((E->isSink() || E->getLocation().getTag()) &&
2986 "Error node must either be a sink or have a tag");
2988 const AnalysisDeclContext *DeclCtx =
2989 E->getLocationContext()->getAnalysisDeclContext();
2990 // The source of autosynthesized body can be handcrafted AST or a model
2991 // file. The locations from handcrafted ASTs have no valid source
2992 // locations and have to be discarded. Locations from model files should
2993 // be preserved for processing and reporting.
2994 if (DeclCtx->isBodyAutosynthesized() &&
2995 !DeclCtx->isBodyAutosynthesizedFromModelFile())
2996 return;
2999 BugReporter::emitReport(std::move(R));
3002 //===----------------------------------------------------------------------===//
3003 // Emitting reports in equivalence classes.
3004 //===----------------------------------------------------------------------===//
3006 namespace {
3008 struct FRIEC_WLItem {
3009 const ExplodedNode *N;
3010 ExplodedNode::const_succ_iterator I, E;
3012 FRIEC_WLItem(const ExplodedNode *n)
3013 : N(n), I(N->succ_begin()), E(N->succ_end()) {}
3016 } // namespace
3018 BugReport *PathSensitiveBugReporter::findReportInEquivalenceClass(
3019 BugReportEquivClass &EQ, SmallVectorImpl<BugReport *> &bugReports) {
3020 // If we don't need to suppress any of the nodes because they are
3021 // post-dominated by a sink, simply add all the nodes in the equivalence class
3022 // to 'Nodes'. Any of the reports will serve as a "representative" report.
3023 assert(EQ.getReports().size() > 0);
3024 const BugType& BT = EQ.getReports()[0]->getBugType();
3025 if (!BT.isSuppressOnSink()) {
3026 BugReport *R = EQ.getReports()[0].get();
3027 for (auto &J : EQ.getReports()) {
3028 if (auto *PR = dyn_cast<PathSensitiveBugReport>(J.get())) {
3029 R = PR;
3030 bugReports.push_back(PR);
3033 return R;
3036 // For bug reports that should be suppressed when all paths are post-dominated
3037 // by a sink node, iterate through the reports in the equivalence class
3038 // until we find one that isn't post-dominated (if one exists). We use a
3039 // DFS traversal of the ExplodedGraph to find a non-sink node. We could write
3040 // this as a recursive function, but we don't want to risk blowing out the
3041 // stack for very long paths.
3042 BugReport *exampleReport = nullptr;
3044 for (const auto &I: EQ.getReports()) {
3045 auto *R = dyn_cast<PathSensitiveBugReport>(I.get());
3046 if (!R)
3047 continue;
3049 const ExplodedNode *errorNode = R->getErrorNode();
3050 if (errorNode->isSink()) {
3051 llvm_unreachable(
3052 "BugType::isSuppressSink() should not be 'true' for sink end nodes");
3054 // No successors? By definition this nodes isn't post-dominated by a sink.
3055 if (errorNode->succ_empty()) {
3056 bugReports.push_back(R);
3057 if (!exampleReport)
3058 exampleReport = R;
3059 continue;
3062 // See if we are in a no-return CFG block. If so, treat this similarly
3063 // to being post-dominated by a sink. This works better when the analysis
3064 // is incomplete and we have never reached the no-return function call(s)
3065 // that we'd inevitably bump into on this path.
3066 if (const CFGBlock *ErrorB = errorNode->getCFGBlock())
3067 if (ErrorB->isInevitablySinking())
3068 continue;
3070 // At this point we know that 'N' is not a sink and it has at least one
3071 // successor. Use a DFS worklist to find a non-sink end-of-path node.
3072 using WLItem = FRIEC_WLItem;
3073 using DFSWorkList = SmallVector<WLItem, 10>;
3075 llvm::DenseMap<const ExplodedNode *, unsigned> Visited;
3077 DFSWorkList WL;
3078 WL.push_back(errorNode);
3079 Visited[errorNode] = 1;
3081 while (!WL.empty()) {
3082 WLItem &WI = WL.back();
3083 assert(!WI.N->succ_empty());
3085 for (; WI.I != WI.E; ++WI.I) {
3086 const ExplodedNode *Succ = *WI.I;
3087 // End-of-path node?
3088 if (Succ->succ_empty()) {
3089 // If we found an end-of-path node that is not a sink.
3090 if (!Succ->isSink()) {
3091 bugReports.push_back(R);
3092 if (!exampleReport)
3093 exampleReport = R;
3094 WL.clear();
3095 break;
3097 // Found a sink? Continue on to the next successor.
3098 continue;
3100 // Mark the successor as visited. If it hasn't been explored,
3101 // enqueue it to the DFS worklist.
3102 unsigned &mark = Visited[Succ];
3103 if (!mark) {
3104 mark = 1;
3105 WL.push_back(Succ);
3106 break;
3110 // The worklist may have been cleared at this point. First
3111 // check if it is empty before checking the last item.
3112 if (!WL.empty() && &WL.back() == &WI)
3113 WL.pop_back();
3117 // ExampleReport will be NULL if all the nodes in the equivalence class
3118 // were post-dominated by sinks.
3119 return exampleReport;
3122 void BugReporter::FlushReport(BugReportEquivClass& EQ) {
3123 SmallVector<BugReport*, 10> bugReports;
3124 BugReport *report = findReportInEquivalenceClass(EQ, bugReports);
3125 if (!report)
3126 return;
3128 // See whether we need to silence the checker/package.
3129 for (const std::string &CheckerOrPackage :
3130 getAnalyzerOptions().SilencedCheckersAndPackages) {
3131 if (report->getBugType().getCheckerName().starts_with(CheckerOrPackage))
3132 return;
3135 ArrayRef<PathDiagnosticConsumer*> Consumers = getPathDiagnosticConsumers();
3136 std::unique_ptr<DiagnosticForConsumerMapTy> Diagnostics =
3137 generateDiagnosticForConsumerMap(report, Consumers, bugReports);
3139 for (auto &P : *Diagnostics) {
3140 PathDiagnosticConsumer *Consumer = P.first;
3141 std::unique_ptr<PathDiagnostic> &PD = P.second;
3143 // If the path is empty, generate a single step path with the location
3144 // of the issue.
3145 if (PD->path.empty()) {
3146 PathDiagnosticLocation L = report->getLocation();
3147 auto piece = std::make_unique<PathDiagnosticEventPiece>(
3148 L, report->getDescription());
3149 for (SourceRange Range : report->getRanges())
3150 piece->addRange(Range);
3151 PD->setEndOfPath(std::move(piece));
3154 PathPieces &Pieces = PD->getMutablePieces();
3155 if (getAnalyzerOptions().ShouldDisplayNotesAsEvents) {
3156 // For path diagnostic consumers that don't support extra notes,
3157 // we may optionally convert those to path notes.
3158 for (const auto &I : llvm::reverse(report->getNotes())) {
3159 PathDiagnosticNotePiece *Piece = I.get();
3160 auto ConvertedPiece = std::make_shared<PathDiagnosticEventPiece>(
3161 Piece->getLocation(), Piece->getString());
3162 for (const auto &R: Piece->getRanges())
3163 ConvertedPiece->addRange(R);
3165 Pieces.push_front(std::move(ConvertedPiece));
3167 } else {
3168 for (const auto &I : llvm::reverse(report->getNotes()))
3169 Pieces.push_front(I);
3172 for (const auto &I : report->getFixits())
3173 Pieces.back()->addFixit(I);
3175 updateExecutedLinesWithDiagnosticPieces(*PD);
3177 // If we are debugging, let's have the entry point as the first note.
3178 if (getAnalyzerOptions().AnalyzerDisplayProgress ||
3179 getAnalyzerOptions().AnalyzerNoteAnalysisEntryPoints) {
3180 const Decl *EntryPoint = getAnalysisEntryPoint();
3181 Pieces.push_front(std::make_shared<PathDiagnosticEventPiece>(
3182 PathDiagnosticLocation{EntryPoint->getLocation(), getSourceManager()},
3183 "[debug] analyzing from " +
3184 AnalysisDeclContext::getFunctionName(EntryPoint)));
3186 Consumer->HandlePathDiagnostic(std::move(PD));
3190 /// Insert all lines participating in the function signature \p Signature
3191 /// into \p ExecutedLines.
3192 static void populateExecutedLinesWithFunctionSignature(
3193 const Decl *Signature, const SourceManager &SM,
3194 FilesToLineNumsMap &ExecutedLines) {
3195 SourceRange SignatureSourceRange;
3196 const Stmt* Body = Signature->getBody();
3197 if (const auto FD = dyn_cast<FunctionDecl>(Signature)) {
3198 SignatureSourceRange = FD->getSourceRange();
3199 } else if (const auto OD = dyn_cast<ObjCMethodDecl>(Signature)) {
3200 SignatureSourceRange = OD->getSourceRange();
3201 } else {
3202 return;
3204 SourceLocation Start = SignatureSourceRange.getBegin();
3205 SourceLocation End = Body ? Body->getSourceRange().getBegin()
3206 : SignatureSourceRange.getEnd();
3207 if (!Start.isValid() || !End.isValid())
3208 return;
3209 unsigned StartLine = SM.getExpansionLineNumber(Start);
3210 unsigned EndLine = SM.getExpansionLineNumber(End);
3212 FileID FID = SM.getFileID(SM.getExpansionLoc(Start));
3213 for (unsigned Line = StartLine; Line <= EndLine; Line++)
3214 ExecutedLines[FID].insert(Line);
3217 static void populateExecutedLinesWithStmt(
3218 const Stmt *S, const SourceManager &SM,
3219 FilesToLineNumsMap &ExecutedLines) {
3220 SourceLocation Loc = S->getSourceRange().getBegin();
3221 if (!Loc.isValid())
3222 return;
3223 SourceLocation ExpansionLoc = SM.getExpansionLoc(Loc);
3224 FileID FID = SM.getFileID(ExpansionLoc);
3225 unsigned LineNo = SM.getExpansionLineNumber(ExpansionLoc);
3226 ExecutedLines[FID].insert(LineNo);
3229 /// \return all executed lines including function signatures on the path
3230 /// starting from \p N.
3231 static std::unique_ptr<FilesToLineNumsMap>
3232 findExecutedLines(const SourceManager &SM, const ExplodedNode *N) {
3233 auto ExecutedLines = std::make_unique<FilesToLineNumsMap>();
3235 while (N) {
3236 if (N->getFirstPred() == nullptr) {
3237 // First node: show signature of the entrance point.
3238 const Decl *D = N->getLocationContext()->getDecl();
3239 populateExecutedLinesWithFunctionSignature(D, SM, *ExecutedLines);
3240 } else if (auto CE = N->getLocationAs<CallEnter>()) {
3241 // Inlined function: show signature.
3242 const Decl* D = CE->getCalleeContext()->getDecl();
3243 populateExecutedLinesWithFunctionSignature(D, SM, *ExecutedLines);
3244 } else if (const Stmt *S = N->getStmtForDiagnostics()) {
3245 populateExecutedLinesWithStmt(S, SM, *ExecutedLines);
3247 // Show extra context for some parent kinds.
3248 const Stmt *P = N->getParentMap().getParent(S);
3250 // The path exploration can die before the node with the associated
3251 // return statement is generated, but we do want to show the whole
3252 // return.
3253 if (const auto *RS = dyn_cast_or_null<ReturnStmt>(P)) {
3254 populateExecutedLinesWithStmt(RS, SM, *ExecutedLines);
3255 P = N->getParentMap().getParent(RS);
3258 if (isa_and_nonnull<SwitchCase, LabelStmt>(P))
3259 populateExecutedLinesWithStmt(P, SM, *ExecutedLines);
3262 N = N->getFirstPred();
3264 return ExecutedLines;
3267 std::unique_ptr<DiagnosticForConsumerMapTy>
3268 BugReporter::generateDiagnosticForConsumerMap(
3269 BugReport *exampleReport, ArrayRef<PathDiagnosticConsumer *> consumers,
3270 ArrayRef<BugReport *> bugReports) {
3271 auto *basicReport = cast<BasicBugReport>(exampleReport);
3272 auto Out = std::make_unique<DiagnosticForConsumerMapTy>();
3273 for (auto *Consumer : consumers)
3274 (*Out)[Consumer] =
3275 generateDiagnosticForBasicReport(basicReport, AnalysisEntryPoint);
3276 return Out;
3279 static PathDiagnosticCallPiece *
3280 getFirstStackedCallToHeaderFile(PathDiagnosticCallPiece *CP,
3281 const SourceManager &SMgr) {
3282 SourceLocation CallLoc = CP->callEnter.asLocation();
3284 // If the call is within a macro, don't do anything (for now).
3285 if (CallLoc.isMacroID())
3286 return nullptr;
3288 assert(AnalysisManager::isInCodeFile(CallLoc, SMgr) &&
3289 "The call piece should not be in a header file.");
3291 // Check if CP represents a path through a function outside of the main file.
3292 if (!AnalysisManager::isInCodeFile(CP->callEnterWithin.asLocation(), SMgr))
3293 return CP;
3295 const PathPieces &Path = CP->path;
3296 if (Path.empty())
3297 return nullptr;
3299 // Check if the last piece in the callee path is a call to a function outside
3300 // of the main file.
3301 if (auto *CPInner = dyn_cast<PathDiagnosticCallPiece>(Path.back().get()))
3302 return getFirstStackedCallToHeaderFile(CPInner, SMgr);
3304 // Otherwise, the last piece is in the main file.
3305 return nullptr;
3308 static void resetDiagnosticLocationToMainFile(PathDiagnostic &PD) {
3309 if (PD.path.empty())
3310 return;
3312 PathDiagnosticPiece *LastP = PD.path.back().get();
3313 assert(LastP);
3314 const SourceManager &SMgr = LastP->getLocation().getManager();
3316 // We only need to check if the report ends inside headers, if the last piece
3317 // is a call piece.
3318 if (auto *CP = dyn_cast<PathDiagnosticCallPiece>(LastP)) {
3319 CP = getFirstStackedCallToHeaderFile(CP, SMgr);
3320 if (CP) {
3321 // Mark the piece.
3322 CP->setAsLastInMainSourceFile();
3324 // Update the path diagnostic message.
3325 const auto *ND = dyn_cast<NamedDecl>(CP->getCallee());
3326 if (ND) {
3327 SmallString<200> buf;
3328 llvm::raw_svector_ostream os(buf);
3329 os << " (within a call to '" << ND->getDeclName() << "')";
3330 PD.appendToDesc(os.str());
3333 // Reset the report containing declaration and location.
3334 PD.setDeclWithIssue(CP->getCaller());
3335 PD.setLocation(CP->getLocation());
3337 return;
3344 std::unique_ptr<DiagnosticForConsumerMapTy>
3345 PathSensitiveBugReporter::generateDiagnosticForConsumerMap(
3346 BugReport *exampleReport, ArrayRef<PathDiagnosticConsumer *> consumers,
3347 ArrayRef<BugReport *> bugReports) {
3348 std::vector<BasicBugReport *> BasicBugReports;
3349 std::vector<PathSensitiveBugReport *> PathSensitiveBugReports;
3350 if (isa<BasicBugReport>(exampleReport))
3351 return BugReporter::generateDiagnosticForConsumerMap(exampleReport,
3352 consumers, bugReports);
3354 // Generate the full path sensitive diagnostic, using the generation scheme
3355 // specified by the PathDiagnosticConsumer. Note that we have to generate
3356 // path diagnostics even for consumers which do not support paths, because
3357 // the BugReporterVisitors may mark this bug as a false positive.
3358 assert(!bugReports.empty());
3359 MaxBugClassSize.updateMax(bugReports.size());
3361 // Avoid copying the whole array because there may be a lot of reports.
3362 ArrayRef<PathSensitiveBugReport *> convertedArrayOfReports(
3363 reinterpret_cast<PathSensitiveBugReport *const *>(&*bugReports.begin()),
3364 reinterpret_cast<PathSensitiveBugReport *const *>(&*bugReports.end()));
3365 std::unique_ptr<DiagnosticForConsumerMapTy> Out = generatePathDiagnostics(
3366 consumers, convertedArrayOfReports);
3368 if (Out->empty())
3369 return Out;
3371 MaxValidBugClassSize.updateMax(bugReports.size());
3373 // Examine the report and see if the last piece is in a header. Reset the
3374 // report location to the last piece in the main source file.
3375 const AnalyzerOptions &Opts = getAnalyzerOptions();
3376 for (auto const &P : *Out)
3377 if (Opts.ShouldReportIssuesInMainSourceFile && !Opts.AnalyzeAll)
3378 resetDiagnosticLocationToMainFile(*P.second);
3380 return Out;
3383 void BugReporter::EmitBasicReport(const Decl *DeclWithIssue,
3384 const CheckerBase *Checker, StringRef Name,
3385 StringRef Category, StringRef Str,
3386 PathDiagnosticLocation Loc,
3387 ArrayRef<SourceRange> Ranges,
3388 ArrayRef<FixItHint> Fixits) {
3389 EmitBasicReport(DeclWithIssue, Checker->getCheckerName(), Name, Category, Str,
3390 Loc, Ranges, Fixits);
3393 void BugReporter::EmitBasicReport(const Decl *DeclWithIssue,
3394 CheckerNameRef CheckName,
3395 StringRef name, StringRef category,
3396 StringRef str, PathDiagnosticLocation Loc,
3397 ArrayRef<SourceRange> Ranges,
3398 ArrayRef<FixItHint> Fixits) {
3399 // 'BT' is owned by BugReporter.
3400 BugType *BT = getBugTypeForName(CheckName, name, category);
3401 auto R = std::make_unique<BasicBugReport>(*BT, str, Loc);
3402 R->setDeclWithIssue(DeclWithIssue);
3403 for (const auto &SR : Ranges)
3404 R->addRange(SR);
3405 for (const auto &FH : Fixits)
3406 R->addFixItHint(FH);
3407 emitReport(std::move(R));
3410 BugType *BugReporter::getBugTypeForName(CheckerNameRef CheckName,
3411 StringRef name, StringRef category) {
3412 SmallString<136> fullDesc;
3413 llvm::raw_svector_ostream(fullDesc) << CheckName.getName() << ":" << name
3414 << ":" << category;
3415 std::unique_ptr<BugType> &BT = StrBugTypes[fullDesc];
3416 if (!BT)
3417 BT = std::make_unique<BugType>(CheckName, name, category);
3418 return BT.get();