1 //===- CheckerManager.cpp - Static Analyzer Checker Manager ---------------===//
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 // Defines the Static Analyzer Checker Manager.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #include "clang/StaticAnalyzer/Core/CheckerManager.h"
14 #include "clang/AST/DeclBase.h"
15 #include "clang/AST/Stmt.h"
16 #include "clang/Analysis/ProgramPoint.h"
17 #include "clang/Basic/JsonSupport.h"
18 #include "clang/Basic/LLVM.h"
19 #include "clang/Driver/DriverDiagnostic.h"
20 #include "clang/StaticAnalyzer/Core/Checker.h"
21 #include "clang/StaticAnalyzer/Core/PathSensitive/CallEvent.h"
22 #include "clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h"
23 #include "clang/StaticAnalyzer/Core/PathSensitive/CoreEngine.h"
24 #include "clang/StaticAnalyzer/Core/PathSensitive/ExprEngine.h"
25 #include "clang/StaticAnalyzer/Core/PathSensitive/SVals.h"
26 #include "llvm/ADT/SmallVector.h"
27 #include "llvm/Support/Casting.h"
28 #include "llvm/Support/ErrorHandling.h"
29 #include <cassert>
30 #include <vector>
31 
32 using namespace clang;
33 using namespace ento;
34 
35 bool CheckerManager::hasPathSensitiveCheckers() const {
36   return !StmtCheckers.empty()              ||
37          !PreObjCMessageCheckers.empty()    ||
38          !PostObjCMessageCheckers.empty()   ||
39          !PreCallCheckers.empty()    ||
40          !PostCallCheckers.empty()   ||
41          !LocationCheckers.empty()          ||
42          !BindCheckers.empty()              ||
43          !EndAnalysisCheckers.empty()       ||
44          !EndFunctionCheckers.empty()           ||
45          !BranchConditionCheckers.empty()   ||
46          !LiveSymbolsCheckers.empty()       ||
47          !DeadSymbolsCheckers.empty()       ||
48          !RegionChangesCheckers.empty()     ||
49          !EvalAssumeCheckers.empty()        ||
50          !EvalCallCheckers.empty();
51 }
52 
53 void CheckerManager::finishedCheckerRegistration() {
54 #ifndef NDEBUG
55   // Make sure that for every event that has listeners, there is at least
56   // one dispatcher registered for it.
57   for (const auto &Event : Events)
58     assert(Event.second.HasDispatcher &&
59            "No dispatcher registered for an event");
60 #endif
61 }
62 
63 void CheckerManager::reportInvalidCheckerOptionValue(
64     const CheckerBase *C, StringRef OptionName, StringRef ExpectedValueDesc) {
65 
66   Context.getDiagnostics()
67       .Report(diag::err_analyzer_checker_option_invalid_input)
68           << (llvm::Twine() + C->getTagDescription() + ":" + OptionName).str()
69           << ExpectedValueDesc;
70 }
71 
72 //===----------------------------------------------------------------------===//
73 // Functions for running checkers for AST traversing..
74 //===----------------------------------------------------------------------===//
75 
76 void CheckerManager::runCheckersOnASTDecl(const Decl *D, AnalysisManager& mgr,
77                                           BugReporter &BR) {
78   assert(D);
79 
80   unsigned DeclKind = D->getKind();
81   CachedDeclCheckers *checkers = nullptr;
82   CachedDeclCheckersMapTy::iterator CCI = CachedDeclCheckersMap.find(DeclKind);
83   if (CCI != CachedDeclCheckersMap.end()) {
84     checkers = &(CCI->second);
85   } else {
86     // Find the checkers that should run for this Decl and cache them.
87     checkers = &CachedDeclCheckersMap[DeclKind];
88     for (const auto &info : DeclCheckers)
89       if (info.IsForDeclFn(D))
90         checkers->push_back(info.CheckFn);
91   }
92 
93   assert(checkers);
94   for (const auto &checker : *checkers)
95     checker(D, mgr, BR);
96 }
97 
98 void CheckerManager::runCheckersOnASTBody(const Decl *D, AnalysisManager& mgr,
99                                           BugReporter &BR) {
100   assert(D && D->hasBody());
101 
102   for (const auto &BodyChecker : BodyCheckers)
103     BodyChecker(D, mgr, BR);
104 }
105 
106 //===----------------------------------------------------------------------===//
107 // Functions for running checkers for path-sensitive checking.
108 //===----------------------------------------------------------------------===//
109 
110 template <typename CHECK_CTX>
111 static void expandGraphWithCheckers(CHECK_CTX checkCtx,
112                                     ExplodedNodeSet &Dst,
113                                     const ExplodedNodeSet &Src) {
114   const NodeBuilderContext &BldrCtx = checkCtx.Eng.getBuilderContext();
115   if (Src.empty())
116     return;
117 
118   typename CHECK_CTX::CheckersTy::const_iterator
119       I = checkCtx.checkers_begin(), E = checkCtx.checkers_end();
120   if (I == E) {
121     Dst.insert(Src);
122     return;
123   }
124 
125   ExplodedNodeSet Tmp1, Tmp2;
126   const ExplodedNodeSet *PrevSet = &Src;
127 
128   for (; I != E; ++I) {
129     ExplodedNodeSet *CurrSet = nullptr;
130     if (I+1 == E)
131       CurrSet = &Dst;
132     else {
133       CurrSet = (PrevSet == &Tmp1) ? &Tmp2 : &Tmp1;
134       CurrSet->clear();
135     }
136 
137     NodeBuilder B(*PrevSet, *CurrSet, BldrCtx);
138     for (const auto &NI : *PrevSet)
139       checkCtx.runChecker(*I, B, NI);
140 
141     // If all the produced transitions are sinks, stop.
142     if (CurrSet->empty())
143       return;
144 
145     // Update which NodeSet is the current one.
146     PrevSet = CurrSet;
147   }
148 }
149 
150 namespace {
151 
152   struct CheckStmtContext {
153     using CheckersTy = SmallVectorImpl<CheckerManager::CheckStmtFunc>;
154 
155     bool IsPreVisit;
156     const CheckersTy &Checkers;
157     const Stmt *S;
158     ExprEngine &Eng;
159     bool WasInlined;
160 
161     CheckStmtContext(bool isPreVisit, const CheckersTy &checkers,
162                      const Stmt *s, ExprEngine &eng, bool wasInlined = false)
163         : IsPreVisit(isPreVisit), Checkers(checkers), S(s), Eng(eng),
164           WasInlined(wasInlined) {}
165 
166     CheckersTy::const_iterator checkers_begin() { return Checkers.begin(); }
167     CheckersTy::const_iterator checkers_end() { return Checkers.end(); }
168 
169     void runChecker(CheckerManager::CheckStmtFunc checkFn,
170                     NodeBuilder &Bldr, ExplodedNode *Pred) {
171       // FIXME: Remove respondsToCallback from CheckerContext;
172       ProgramPoint::Kind K =  IsPreVisit ? ProgramPoint::PreStmtKind :
173                                            ProgramPoint::PostStmtKind;
174       const ProgramPoint &L = ProgramPoint::getProgramPoint(S, K,
175                                 Pred->getLocationContext(), checkFn.Checker);
176       CheckerContext C(Bldr, Eng, Pred, L, WasInlined);
177       checkFn(S, C);
178     }
179   };
180 
181 } // namespace
182 
183 /// Run checkers for visiting Stmts.
184 void CheckerManager::runCheckersForStmt(bool isPreVisit,
185                                         ExplodedNodeSet &Dst,
186                                         const ExplodedNodeSet &Src,
187                                         const Stmt *S,
188                                         ExprEngine &Eng,
189                                         bool WasInlined) {
190   CheckStmtContext C(isPreVisit, getCachedStmtCheckersFor(S, isPreVisit),
191                      S, Eng, WasInlined);
192   expandGraphWithCheckers(C, Dst, Src);
193 }
194 
195 namespace {
196 
197   struct CheckObjCMessageContext {
198     using CheckersTy = std::vector<CheckerManager::CheckObjCMessageFunc>;
199 
200     ObjCMessageVisitKind Kind;
201     bool WasInlined;
202     const CheckersTy &Checkers;
203     const ObjCMethodCall &Msg;
204     ExprEngine &Eng;
205 
206     CheckObjCMessageContext(ObjCMessageVisitKind visitKind,
207                             const CheckersTy &checkers,
208                             const ObjCMethodCall &msg, ExprEngine &eng,
209                             bool wasInlined)
210         : Kind(visitKind), WasInlined(wasInlined), Checkers(checkers), Msg(msg),
211           Eng(eng) {}
212 
213     CheckersTy::const_iterator checkers_begin() { return Checkers.begin(); }
214     CheckersTy::const_iterator checkers_end() { return Checkers.end(); }
215 
216     void runChecker(CheckerManager::CheckObjCMessageFunc checkFn,
217                     NodeBuilder &Bldr, ExplodedNode *Pred) {
218       bool IsPreVisit;
219 
220       switch (Kind) {
221         case ObjCMessageVisitKind::Pre:
222           IsPreVisit = true;
223           break;
224         case ObjCMessageVisitKind::MessageNil:
225         case ObjCMessageVisitKind::Post:
226           IsPreVisit = false;
227           break;
228       }
229 
230       const ProgramPoint &L = Msg.getProgramPoint(IsPreVisit,checkFn.Checker);
231       CheckerContext C(Bldr, Eng, Pred, L, WasInlined);
232 
233       checkFn(*Msg.cloneWithState<ObjCMethodCall>(Pred->getState()), C);
234     }
235   };
236 
237 } // namespace
238 
239 /// Run checkers for visiting obj-c messages.
240 void CheckerManager::runCheckersForObjCMessage(ObjCMessageVisitKind visitKind,
241                                                ExplodedNodeSet &Dst,
242                                                const ExplodedNodeSet &Src,
243                                                const ObjCMethodCall &msg,
244                                                ExprEngine &Eng,
245                                                bool WasInlined) {
246   auto &checkers = getObjCMessageCheckers(visitKind);
247   CheckObjCMessageContext C(visitKind, checkers, msg, Eng, WasInlined);
248   expandGraphWithCheckers(C, Dst, Src);
249 }
250 
251 const std::vector<CheckerManager::CheckObjCMessageFunc> &
252 CheckerManager::getObjCMessageCheckers(ObjCMessageVisitKind Kind) {
253   switch (Kind) {
254   case ObjCMessageVisitKind::Pre:
255     return PreObjCMessageCheckers;
256     break;
257   case ObjCMessageVisitKind::Post:
258     return PostObjCMessageCheckers;
259   case ObjCMessageVisitKind::MessageNil:
260     return ObjCMessageNilCheckers;
261   }
262   llvm_unreachable("Unknown Kind");
263 }
264 
265 namespace {
266 
267   // FIXME: This has all the same signatures as CheckObjCMessageContext.
268   // Is there a way we can merge the two?
269   struct CheckCallContext {
270     using CheckersTy = std::vector<CheckerManager::CheckCallFunc>;
271 
272     bool IsPreVisit, WasInlined;
273     const CheckersTy &Checkers;
274     const CallEvent &Call;
275     ExprEngine &Eng;
276 
277     CheckCallContext(bool isPreVisit, const CheckersTy &checkers,
278                      const CallEvent &call, ExprEngine &eng,
279                      bool wasInlined)
280         : IsPreVisit(isPreVisit), WasInlined(wasInlined), Checkers(checkers),
281           Call(call), Eng(eng) {}
282 
283     CheckersTy::const_iterator checkers_begin() { return Checkers.begin(); }
284     CheckersTy::const_iterator checkers_end() { return Checkers.end(); }
285 
286     void runChecker(CheckerManager::CheckCallFunc checkFn,
287                     NodeBuilder &Bldr, ExplodedNode *Pred) {
288       const ProgramPoint &L = Call.getProgramPoint(IsPreVisit,checkFn.Checker);
289       CheckerContext C(Bldr, Eng, Pred, L, WasInlined);
290 
291       checkFn(*Call.cloneWithState(Pred->getState()), C);
292     }
293   };
294 
295 } // namespace
296 
297 /// Run checkers for visiting an abstract call event.
298 void CheckerManager::runCheckersForCallEvent(bool isPreVisit,
299                                              ExplodedNodeSet &Dst,
300                                              const ExplodedNodeSet &Src,
301                                              const CallEvent &Call,
302                                              ExprEngine &Eng,
303                                              bool WasInlined) {
304   CheckCallContext C(isPreVisit,
305                      isPreVisit ? PreCallCheckers
306                                 : PostCallCheckers,
307                      Call, Eng, WasInlined);
308   expandGraphWithCheckers(C, Dst, Src);
309 }
310 
311 namespace {
312 
313   struct CheckLocationContext {
314     using CheckersTy = std::vector<CheckerManager::CheckLocationFunc>;
315 
316     const CheckersTy &Checkers;
317     SVal Loc;
318     bool IsLoad;
319     const Stmt *NodeEx; /* Will become a CFGStmt */
320     const Stmt *BoundEx;
321     ExprEngine &Eng;
322 
323     CheckLocationContext(const CheckersTy &checkers,
324                          SVal loc, bool isLoad, const Stmt *NodeEx,
325                          const Stmt *BoundEx,
326                          ExprEngine &eng)
327         : Checkers(checkers), Loc(loc), IsLoad(isLoad), NodeEx(NodeEx),
328           BoundEx(BoundEx), Eng(eng) {}
329 
330     CheckersTy::const_iterator checkers_begin() { return Checkers.begin(); }
331     CheckersTy::const_iterator checkers_end() { return Checkers.end(); }
332 
333     void runChecker(CheckerManager::CheckLocationFunc checkFn,
334                     NodeBuilder &Bldr, ExplodedNode *Pred) {
335       ProgramPoint::Kind K =  IsLoad ? ProgramPoint::PreLoadKind :
336                                        ProgramPoint::PreStoreKind;
337       const ProgramPoint &L =
338         ProgramPoint::getProgramPoint(NodeEx, K,
339                                       Pred->getLocationContext(),
340                                       checkFn.Checker);
341       CheckerContext C(Bldr, Eng, Pred, L);
342       checkFn(Loc, IsLoad, BoundEx, C);
343     }
344   };
345 
346 } // namespace
347 
348 /// Run checkers for load/store of a location.
349 
350 void CheckerManager::runCheckersForLocation(ExplodedNodeSet &Dst,
351                                             const ExplodedNodeSet &Src,
352                                             SVal location, bool isLoad,
353                                             const Stmt *NodeEx,
354                                             const Stmt *BoundEx,
355                                             ExprEngine &Eng) {
356   CheckLocationContext C(LocationCheckers, location, isLoad, NodeEx,
357                          BoundEx, Eng);
358   expandGraphWithCheckers(C, Dst, Src);
359 }
360 
361 namespace {
362 
363   struct CheckBindContext {
364     using CheckersTy = std::vector<CheckerManager::CheckBindFunc>;
365 
366     const CheckersTy &Checkers;
367     SVal Loc;
368     SVal Val;
369     const Stmt *S;
370     ExprEngine &Eng;
371     const ProgramPoint &PP;
372 
373     CheckBindContext(const CheckersTy &checkers,
374                      SVal loc, SVal val, const Stmt *s, ExprEngine &eng,
375                      const ProgramPoint &pp)
376         : Checkers(checkers), Loc(loc), Val(val), S(s), Eng(eng), PP(pp) {}
377 
378     CheckersTy::const_iterator checkers_begin() { return Checkers.begin(); }
379     CheckersTy::const_iterator checkers_end() { return Checkers.end(); }
380 
381     void runChecker(CheckerManager::CheckBindFunc checkFn,
382                     NodeBuilder &Bldr, ExplodedNode *Pred) {
383       const ProgramPoint &L = PP.withTag(checkFn.Checker);
384       CheckerContext C(Bldr, Eng, Pred, L);
385 
386       checkFn(Loc, Val, S, C);
387     }
388   };
389 
390 } // namespace
391 
392 /// Run checkers for binding of a value to a location.
393 void CheckerManager::runCheckersForBind(ExplodedNodeSet &Dst,
394                                         const ExplodedNodeSet &Src,
395                                         SVal location, SVal val,
396                                         const Stmt *S, ExprEngine &Eng,
397                                         const ProgramPoint &PP) {
398   CheckBindContext C(BindCheckers, location, val, S, Eng, PP);
399   expandGraphWithCheckers(C, Dst, Src);
400 }
401 
402 void CheckerManager::runCheckersForEndAnalysis(ExplodedGraph &G,
403                                                BugReporter &BR,
404                                                ExprEngine &Eng) {
405   for (const auto &EndAnalysisChecker : EndAnalysisCheckers)
406     EndAnalysisChecker(G, BR, Eng);
407 }
408 
409 namespace {
410 
411 struct CheckBeginFunctionContext {
412   using CheckersTy = std::vector<CheckerManager::CheckBeginFunctionFunc>;
413 
414   const CheckersTy &Checkers;
415   ExprEngine &Eng;
416   const ProgramPoint &PP;
417 
418   CheckBeginFunctionContext(const CheckersTy &Checkers, ExprEngine &Eng,
419                             const ProgramPoint &PP)
420       : Checkers(Checkers), Eng(Eng), PP(PP) {}
421 
422   CheckersTy::const_iterator checkers_begin() { return Checkers.begin(); }
423   CheckersTy::const_iterator checkers_end() { return Checkers.end(); }
424 
425   void runChecker(CheckerManager::CheckBeginFunctionFunc checkFn,
426                   NodeBuilder &Bldr, ExplodedNode *Pred) {
427     const ProgramPoint &L = PP.withTag(checkFn.Checker);
428     CheckerContext C(Bldr, Eng, Pred, L);
429 
430     checkFn(C);
431   }
432 };
433 
434 } // namespace
435 
436 void CheckerManager::runCheckersForBeginFunction(ExplodedNodeSet &Dst,
437                                                  const BlockEdge &L,
438                                                  ExplodedNode *Pred,
439                                                  ExprEngine &Eng) {
440   ExplodedNodeSet Src;
441   Src.insert(Pred);
442   CheckBeginFunctionContext C(BeginFunctionCheckers, Eng, L);
443   expandGraphWithCheckers(C, Dst, Src);
444 }
445 
446 /// Run checkers for end of path.
447 // Note, We do not chain the checker output (like in expandGraphWithCheckers)
448 // for this callback since end of path nodes are expected to be final.
449 void CheckerManager::runCheckersForEndFunction(NodeBuilderContext &BC,
450                                                ExplodedNodeSet &Dst,
451                                                ExplodedNode *Pred,
452                                                ExprEngine &Eng,
453                                                const ReturnStmt *RS) {
454   // We define the builder outside of the loop because if at least one checker
455   // creates a successor for Pred, we do not need to generate an
456   // autotransition for it.
457   NodeBuilder Bldr(Pred, Dst, BC);
458   for (const auto &checkFn : EndFunctionCheckers) {
459     const ProgramPoint &L =
460         FunctionExitPoint(RS, Pred->getLocationContext(), checkFn.Checker);
461     CheckerContext C(Bldr, Eng, Pred, L);
462     checkFn(RS, C);
463   }
464 }
465 
466 namespace {
467 
468   struct CheckBranchConditionContext {
469     using CheckersTy = std::vector<CheckerManager::CheckBranchConditionFunc>;
470 
471     const CheckersTy &Checkers;
472     const Stmt *Condition;
473     ExprEngine &Eng;
474 
475     CheckBranchConditionContext(const CheckersTy &checkers,
476                                 const Stmt *Cond, ExprEngine &eng)
477         : Checkers(checkers), Condition(Cond), Eng(eng) {}
478 
479     CheckersTy::const_iterator checkers_begin() { return Checkers.begin(); }
480     CheckersTy::const_iterator checkers_end() { return Checkers.end(); }
481 
482     void runChecker(CheckerManager::CheckBranchConditionFunc checkFn,
483                     NodeBuilder &Bldr, ExplodedNode *Pred) {
484       ProgramPoint L = PostCondition(Condition, Pred->getLocationContext(),
485                                      checkFn.Checker);
486       CheckerContext C(Bldr, Eng, Pred, L);
487       checkFn(Condition, C);
488     }
489   };
490 
491 } // namespace
492 
493 /// Run checkers for branch condition.
494 void CheckerManager::runCheckersForBranchCondition(const Stmt *Condition,
495                                                    ExplodedNodeSet &Dst,
496                                                    ExplodedNode *Pred,
497                                                    ExprEngine &Eng) {
498   ExplodedNodeSet Src;
499   Src.insert(Pred);
500   CheckBranchConditionContext C(BranchConditionCheckers, Condition, Eng);
501   expandGraphWithCheckers(C, Dst, Src);
502 }
503 
504 namespace {
505 
506   struct CheckNewAllocatorContext {
507     using CheckersTy = std::vector<CheckerManager::CheckNewAllocatorFunc>;
508 
509     const CheckersTy &Checkers;
510     const CXXNewExpr *NE;
511     SVal Target;
512     bool WasInlined;
513     ExprEngine &Eng;
514 
515     CheckNewAllocatorContext(const CheckersTy &Checkers, const CXXNewExpr *NE,
516                              SVal Target, bool WasInlined, ExprEngine &Eng)
517         : Checkers(Checkers), NE(NE), Target(Target), WasInlined(WasInlined),
518           Eng(Eng) {}
519 
520     CheckersTy::const_iterator checkers_begin() { return Checkers.begin(); }
521     CheckersTy::const_iterator checkers_end() { return Checkers.end(); }
522 
523     void runChecker(CheckerManager::CheckNewAllocatorFunc checkFn,
524                     NodeBuilder &Bldr, ExplodedNode *Pred) {
525       ProgramPoint L = PostAllocatorCall(NE, Pred->getLocationContext());
526       CheckerContext C(Bldr, Eng, Pred, L, WasInlined);
527       checkFn(NE, Target, C);
528     }
529   };
530 
531 } // namespace
532 
533 void CheckerManager::runCheckersForNewAllocator(
534     const CXXNewExpr *NE, SVal Target, ExplodedNodeSet &Dst, ExplodedNode *Pred,
535     ExprEngine &Eng, bool WasInlined) {
536   ExplodedNodeSet Src;
537   Src.insert(Pred);
538   CheckNewAllocatorContext C(NewAllocatorCheckers, NE, Target, WasInlined, Eng);
539   expandGraphWithCheckers(C, Dst, Src);
540 }
541 
542 /// Run checkers for live symbols.
543 void CheckerManager::runCheckersForLiveSymbols(ProgramStateRef state,
544                                                SymbolReaper &SymReaper) {
545   for (const auto &LiveSymbolsChecker : LiveSymbolsCheckers)
546     LiveSymbolsChecker(state, SymReaper);
547 }
548 
549 namespace {
550 
551   struct CheckDeadSymbolsContext {
552     using CheckersTy = std::vector<CheckerManager::CheckDeadSymbolsFunc>;
553 
554     const CheckersTy &Checkers;
555     SymbolReaper &SR;
556     const Stmt *S;
557     ExprEngine &Eng;
558     ProgramPoint::Kind ProgarmPointKind;
559 
560     CheckDeadSymbolsContext(const CheckersTy &checkers, SymbolReaper &sr,
561                             const Stmt *s, ExprEngine &eng,
562                             ProgramPoint::Kind K)
563         : Checkers(checkers), SR(sr), S(s), Eng(eng), ProgarmPointKind(K) {}
564 
565     CheckersTy::const_iterator checkers_begin() { return Checkers.begin(); }
566     CheckersTy::const_iterator checkers_end() { return Checkers.end(); }
567 
568     void runChecker(CheckerManager::CheckDeadSymbolsFunc checkFn,
569                     NodeBuilder &Bldr, ExplodedNode *Pred) {
570       const ProgramPoint &L = ProgramPoint::getProgramPoint(S, ProgarmPointKind,
571                                 Pred->getLocationContext(), checkFn.Checker);
572       CheckerContext C(Bldr, Eng, Pred, L);
573 
574       // Note, do not pass the statement to the checkers without letting them
575       // differentiate if we ran remove dead bindings before or after the
576       // statement.
577       checkFn(SR, C);
578     }
579   };
580 
581 } // namespace
582 
583 /// Run checkers for dead symbols.
584 void CheckerManager::runCheckersForDeadSymbols(ExplodedNodeSet &Dst,
585                                                const ExplodedNodeSet &Src,
586                                                SymbolReaper &SymReaper,
587                                                const Stmt *S,
588                                                ExprEngine &Eng,
589                                                ProgramPoint::Kind K) {
590   CheckDeadSymbolsContext C(DeadSymbolsCheckers, SymReaper, S, Eng, K);
591   expandGraphWithCheckers(C, Dst, Src);
592 }
593 
594 /// Run checkers for region changes.
595 ProgramStateRef
596 CheckerManager::runCheckersForRegionChanges(ProgramStateRef state,
597                                             const InvalidatedSymbols *invalidated,
598                                             ArrayRef<const MemRegion *> ExplicitRegions,
599                                             ArrayRef<const MemRegion *> Regions,
600                                             const LocationContext *LCtx,
601                                             const CallEvent *Call) {
602   for (const auto &RegionChangesChecker : RegionChangesCheckers) {
603     // If any checker declares the state infeasible (or if it starts that way),
604     // bail out.
605     if (!state)
606       return nullptr;
607     state = RegionChangesChecker(state, invalidated, ExplicitRegions, Regions,
608                                  LCtx, Call);
609   }
610   return state;
611 }
612 
613 /// Run checkers to process symbol escape event.
614 ProgramStateRef
615 CheckerManager::runCheckersForPointerEscape(ProgramStateRef State,
616                                    const InvalidatedSymbols &Escaped,
617                                    const CallEvent *Call,
618                                    PointerEscapeKind Kind,
619                                    RegionAndSymbolInvalidationTraits *ETraits) {
620   assert((Call != nullptr ||
621           (Kind != PSK_DirectEscapeOnCall &&
622            Kind != PSK_IndirectEscapeOnCall)) &&
623          "Call must not be NULL when escaping on call");
624   for (const auto &PointerEscapeChecker : PointerEscapeCheckers) {
625     // If any checker declares the state infeasible (or if it starts that
626     //  way), bail out.
627     if (!State)
628       return nullptr;
629     State = PointerEscapeChecker(State, Escaped, Call, Kind, ETraits);
630   }
631   return State;
632 }
633 
634 /// Run checkers for handling assumptions on symbolic values.
635 ProgramStateRef
636 CheckerManager::runCheckersForEvalAssume(ProgramStateRef state,
637                                          SVal Cond, bool Assumption) {
638   for (const auto &EvalAssumeChecker : EvalAssumeCheckers) {
639     // If any checker declares the state infeasible (or if it starts that way),
640     // bail out.
641     if (!state)
642       return nullptr;
643     state = EvalAssumeChecker(state, Cond, Assumption);
644   }
645   return state;
646 }
647 
648 /// Run checkers for evaluating a call.
649 /// Only one checker will evaluate the call.
650 void CheckerManager::runCheckersForEvalCall(ExplodedNodeSet &Dst,
651                                             const ExplodedNodeSet &Src,
652                                             const CallEvent &Call,
653                                             ExprEngine &Eng) {
654   for (const auto Pred : Src) {
655     bool anyEvaluated = false;
656 
657     ExplodedNodeSet checkDst;
658     NodeBuilder B(Pred, checkDst, Eng.getBuilderContext());
659 
660     // Check if any of the EvalCall callbacks can evaluate the call.
661     for (const auto &EvalCallChecker : EvalCallCheckers) {
662       // TODO: Support the situation when the call doesn't correspond
663       // to any Expr.
664       ProgramPoint L = ProgramPoint::getProgramPoint(
665           cast<CallExpr>(Call.getOriginExpr()),
666           ProgramPoint::PostStmtKind,
667           Pred->getLocationContext(),
668           EvalCallChecker.Checker);
669       bool evaluated = false;
670       { // CheckerContext generates transitions(populates checkDest) on
671         // destruction, so introduce the scope to make sure it gets properly
672         // populated.
673         CheckerContext C(B, Eng, Pred, L);
674         evaluated = EvalCallChecker(Call, C);
675       }
676       assert(!(evaluated && anyEvaluated)
677              && "There are more than one checkers evaluating the call");
678       if (evaluated) {
679         anyEvaluated = true;
680         Dst.insert(checkDst);
681 #ifdef NDEBUG
682         break; // on release don't check that no other checker also evals.
683 #endif
684       }
685     }
686 
687     // If none of the checkers evaluated the call, ask ExprEngine to handle it.
688     if (!anyEvaluated) {
689       NodeBuilder B(Pred, Dst, Eng.getBuilderContext());
690       Eng.defaultEvalCall(B, Pred, Call);
691     }
692   }
693 }
694 
695 /// Run checkers for the entire Translation Unit.
696 void CheckerManager::runCheckersOnEndOfTranslationUnit(
697                                                   const TranslationUnitDecl *TU,
698                                                   AnalysisManager &mgr,
699                                                   BugReporter &BR) {
700   for (const auto &EndOfTranslationUnitChecker : EndOfTranslationUnitCheckers)
701     EndOfTranslationUnitChecker(TU, mgr, BR);
702 }
703 
704 void CheckerManager::runCheckersForPrintStateJson(raw_ostream &Out,
705                                                   ProgramStateRef State,
706                                                   const char *NL,
707                                                   unsigned int Space,
708                                                   bool IsDot) const {
709   Indent(Out, Space, IsDot) << "\"checker_messages\": ";
710 
711   // Create a temporary stream to see whether we have any message.
712   SmallString<1024> TempBuf;
713   llvm::raw_svector_ostream TempOut(TempBuf);
714   unsigned int InnerSpace = Space + 2;
715 
716   // Create the new-line in JSON with enough space.
717   SmallString<128> NewLine;
718   llvm::raw_svector_ostream NLOut(NewLine);
719   NLOut << "\", " << NL;                     // Inject the ending and a new line
720   Indent(NLOut, InnerSpace, IsDot) << "\"";  // then begin the next message.
721 
722   ++Space;
723   bool HasMessage = false;
724 
725   // Store the last CheckerTag.
726   const void *LastCT = nullptr;
727   for (const auto &CT : CheckerTags) {
728     // See whether the current checker has a message.
729     CT.second->printState(TempOut, State, /*NL=*/NewLine.c_str(), /*Sep=*/"");
730 
731     if (TempBuf.empty())
732       continue;
733 
734     if (!HasMessage) {
735       Out << '[' << NL;
736       HasMessage = true;
737     }
738 
739     LastCT = &CT;
740     TempBuf.clear();
741   }
742 
743   for (const auto &CT : CheckerTags) {
744     // See whether the current checker has a message.
745     CT.second->printState(TempOut, State, /*NL=*/NewLine.c_str(), /*Sep=*/"");
746 
747     if (TempBuf.empty())
748       continue;
749 
750     Indent(Out, Space, IsDot)
751         << "{ \"checker\": \"" << CT.second->getCheckerName().getName()
752         << "\", \"messages\": [" << NL;
753     Indent(Out, InnerSpace, IsDot)
754         << '\"' << TempBuf.str().trim() << '\"' << NL;
755     Indent(Out, Space, IsDot) << "]}";
756 
757     if (&CT != LastCT)
758       Out << ',';
759     Out << NL;
760 
761     TempBuf.clear();
762   }
763 
764   // It is the last element of the 'program_state' so do not add a comma.
765   if (HasMessage)
766     Indent(Out, --Space, IsDot) << "]";
767   else
768     Out << "null";
769 
770   Out << NL;
771 }
772 
773 //===----------------------------------------------------------------------===//
774 // Internal registration functions for AST traversing.
775 //===----------------------------------------------------------------------===//
776 
777 void CheckerManager::_registerForDecl(CheckDeclFunc checkfn,
778                                       HandlesDeclFunc isForDeclFn) {
779   DeclCheckerInfo info = { checkfn, isForDeclFn };
780   DeclCheckers.push_back(info);
781 }
782 
783 void CheckerManager::_registerForBody(CheckDeclFunc checkfn) {
784   BodyCheckers.push_back(checkfn);
785 }
786 
787 //===----------------------------------------------------------------------===//
788 // Internal registration functions for path-sensitive checking.
789 //===----------------------------------------------------------------------===//
790 
791 void CheckerManager::_registerForPreStmt(CheckStmtFunc checkfn,
792                                          HandlesStmtFunc isForStmtFn) {
793   StmtCheckerInfo info = { checkfn, isForStmtFn, /*IsPreVisit*/true };
794   StmtCheckers.push_back(info);
795 }
796 
797 void CheckerManager::_registerForPostStmt(CheckStmtFunc checkfn,
798                                           HandlesStmtFunc isForStmtFn) {
799   StmtCheckerInfo info = { checkfn, isForStmtFn, /*IsPreVisit*/false };
800   StmtCheckers.push_back(info);
801 }
802 
803 void CheckerManager::_registerForPreObjCMessage(CheckObjCMessageFunc checkfn) {
804   PreObjCMessageCheckers.push_back(checkfn);
805 }
806 
807 void CheckerManager::_registerForObjCMessageNil(CheckObjCMessageFunc checkfn) {
808   ObjCMessageNilCheckers.push_back(checkfn);
809 }
810 
811 void CheckerManager::_registerForPostObjCMessage(CheckObjCMessageFunc checkfn) {
812   PostObjCMessageCheckers.push_back(checkfn);
813 }
814 
815 void CheckerManager::_registerForPreCall(CheckCallFunc checkfn) {
816   PreCallCheckers.push_back(checkfn);
817 }
818 void CheckerManager::_registerForPostCall(CheckCallFunc checkfn) {
819   PostCallCheckers.push_back(checkfn);
820 }
821 
822 void CheckerManager::_registerForLocation(CheckLocationFunc checkfn) {
823   LocationCheckers.push_back(checkfn);
824 }
825 
826 void CheckerManager::_registerForBind(CheckBindFunc checkfn) {
827   BindCheckers.push_back(checkfn);
828 }
829 
830 void CheckerManager::_registerForEndAnalysis(CheckEndAnalysisFunc checkfn) {
831   EndAnalysisCheckers.push_back(checkfn);
832 }
833 
834 void CheckerManager::_registerForBeginFunction(CheckBeginFunctionFunc checkfn) {
835   BeginFunctionCheckers.push_back(checkfn);
836 }
837 
838 void CheckerManager::_registerForEndFunction(CheckEndFunctionFunc checkfn) {
839   EndFunctionCheckers.push_back(checkfn);
840 }
841 
842 void CheckerManager::_registerForBranchCondition(
843                                              CheckBranchConditionFunc checkfn) {
844   BranchConditionCheckers.push_back(checkfn);
845 }
846 
847 void CheckerManager::_registerForNewAllocator(CheckNewAllocatorFunc checkfn) {
848   NewAllocatorCheckers.push_back(checkfn);
849 }
850 
851 void CheckerManager::_registerForLiveSymbols(CheckLiveSymbolsFunc checkfn) {
852   LiveSymbolsCheckers.push_back(checkfn);
853 }
854 
855 void CheckerManager::_registerForDeadSymbols(CheckDeadSymbolsFunc checkfn) {
856   DeadSymbolsCheckers.push_back(checkfn);
857 }
858 
859 void CheckerManager::_registerForRegionChanges(CheckRegionChangesFunc checkfn) {
860   RegionChangesCheckers.push_back(checkfn);
861 }
862 
863 void CheckerManager::_registerForPointerEscape(CheckPointerEscapeFunc checkfn){
864   PointerEscapeCheckers.push_back(checkfn);
865 }
866 
867 void CheckerManager::_registerForConstPointerEscape(
868                                           CheckPointerEscapeFunc checkfn) {
869   PointerEscapeCheckers.push_back(checkfn);
870 }
871 
872 void CheckerManager::_registerForEvalAssume(EvalAssumeFunc checkfn) {
873   EvalAssumeCheckers.push_back(checkfn);
874 }
875 
876 void CheckerManager::_registerForEvalCall(EvalCallFunc checkfn) {
877   EvalCallCheckers.push_back(checkfn);
878 }
879 
880 void CheckerManager::_registerForEndOfTranslationUnit(
881                                             CheckEndOfTranslationUnit checkfn) {
882   EndOfTranslationUnitCheckers.push_back(checkfn);
883 }
884 
885 //===----------------------------------------------------------------------===//
886 // Implementation details.
887 //===----------------------------------------------------------------------===//
888 
889 const CheckerManager::CachedStmtCheckers &
890 CheckerManager::getCachedStmtCheckersFor(const Stmt *S, bool isPreVisit) {
891   assert(S);
892 
893   unsigned Key = (S->getStmtClass() << 1) | unsigned(isPreVisit);
894   CachedStmtCheckersMapTy::iterator CCI = CachedStmtCheckersMap.find(Key);
895   if (CCI != CachedStmtCheckersMap.end())
896     return CCI->second;
897 
898   // Find the checkers that should run for this Stmt and cache them.
899   CachedStmtCheckers &Checkers = CachedStmtCheckersMap[Key];
900   for (const auto &Info : StmtCheckers)
901     if (Info.IsPreVisit == isPreVisit && Info.IsForStmtFn(S))
902       Checkers.push_back(Info.CheckFn);
903   return Checkers;
904 }
905 
906 CheckerManager::~CheckerManager() {
907   for (const auto &CheckerDtor : CheckerDtors)
908     CheckerDtor();
909 }
910