clang  9.0.0svn
Consumed.cpp
Go to the documentation of this file.
1 //===- Consumed.cpp -------------------------------------------------------===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // A intra-procedural analysis for checking consumed properties. This is based,
11 // in part, on research on linear types.
12 //
13 //===----------------------------------------------------------------------===//
14 
16 #include "clang/AST/Attr.h"
17 #include "clang/AST/Decl.h"
18 #include "clang/AST/DeclCXX.h"
19 #include "clang/AST/Expr.h"
20 #include "clang/AST/ExprCXX.h"
21 #include "clang/AST/Stmt.h"
22 #include "clang/AST/StmtVisitor.h"
23 #include "clang/AST/Type.h"
26 #include "clang/Analysis/CFG.h"
27 #include "clang/Basic/LLVM.h"
30 #include "llvm/ADT/DenseMap.h"
31 #include "llvm/ADT/Optional.h"
32 #include "llvm/ADT/STLExtras.h"
33 #include "llvm/ADT/StringRef.h"
34 #include "llvm/Support/Casting.h"
35 #include "llvm/Support/ErrorHandling.h"
36 #include <cassert>
37 #include <memory>
38 #include <utility>
39 
40 // TODO: Adjust states of args to constructors in the same way that arguments to
41 // function calls are handled.
42 // TODO: Use information from tests in for- and while-loop conditional.
43 // TODO: Add notes about the actual and expected state for
44 // TODO: Correctly identify unreachable blocks when chaining boolean operators.
45 // TODO: Adjust the parser and AttributesList class to support lists of
46 // identifiers.
47 // TODO: Warn about unreachable code.
48 // TODO: Switch to using a bitmap to track unreachable blocks.
49 // TODO: Handle variable definitions, e.g. bool valid = x.isValid();
50 // if (valid) ...; (Deferred)
51 // TODO: Take notes on state transitions to provide better warning messages.
52 // (Deferred)
53 // TODO: Test nested conditionals: A) Checking the same value multiple times,
54 // and 2) Checking different values. (Deferred)
55 
56 using namespace clang;
57 using namespace consumed;
58 
59 // Key method definition
61 
62 static SourceLocation getFirstStmtLoc(const CFGBlock *Block) {
63  // Find the source location of the first statement in the block, if the block
64  // is not empty.
65  for (const auto &B : *Block)
66  if (Optional<CFGStmt> CS = B.getAs<CFGStmt>())
67  return CS->getStmt()->getBeginLoc();
68 
69  // Block is empty.
70  // If we have one successor, return the first statement in that block
71  if (Block->succ_size() == 1 && *Block->succ_begin())
72  return getFirstStmtLoc(*Block->succ_begin());
73 
74  return {};
75 }
76 
77 static SourceLocation getLastStmtLoc(const CFGBlock *Block) {
78  // Find the source location of the last statement in the block, if the block
79  // is not empty.
80  if (const Stmt *StmtNode = Block->getTerminator()) {
81  return StmtNode->getBeginLoc();
82  } else {
83  for (CFGBlock::const_reverse_iterator BI = Block->rbegin(),
84  BE = Block->rend(); BI != BE; ++BI) {
85  if (Optional<CFGStmt> CS = BI->getAs<CFGStmt>())
86  return CS->getStmt()->getBeginLoc();
87  }
88  }
89 
90  // If we have one successor, return the first statement in that block
91  SourceLocation Loc;
92  if (Block->succ_size() == 1 && *Block->succ_begin())
93  Loc = getFirstStmtLoc(*Block->succ_begin());
94  if (Loc.isValid())
95  return Loc;
96 
97  // If we have one predecessor, return the last statement in that block
98  if (Block->pred_size() == 1 && *Block->pred_begin())
99  return getLastStmtLoc(*Block->pred_begin());
100 
101  return Loc;
102 }
103 
105  switch (State) {
106  case CS_Unconsumed:
107  return CS_Consumed;
108  case CS_Consumed:
109  return CS_Unconsumed;
110  case CS_None:
111  return CS_None;
112  case CS_Unknown:
113  return CS_Unknown;
114  }
115  llvm_unreachable("invalid enum");
116 }
117 
118 static bool isCallableInState(const CallableWhenAttr *CWAttr,
120  for (const auto &S : CWAttr->callableStates()) {
121  ConsumedState MappedAttrState = CS_None;
122 
123  switch (S) {
125  MappedAttrState = CS_Unknown;
126  break;
127 
128  case CallableWhenAttr::Unconsumed:
129  MappedAttrState = CS_Unconsumed;
130  break;
131 
132  case CallableWhenAttr::Consumed:
133  MappedAttrState = CS_Consumed;
134  break;
135  }
136 
137  if (MappedAttrState == State)
138  return true;
139  }
140 
141  return false;
142 }
143 
144 static bool isConsumableType(const QualType &QT) {
145  if (QT->isPointerType() || QT->isReferenceType())
146  return false;
147 
148  if (const CXXRecordDecl *RD = QT->getAsCXXRecordDecl())
149  return RD->hasAttr<ConsumableAttr>();
150 
151  return false;
152 }
153 
154 static bool isAutoCastType(const QualType &QT) {
155  if (QT->isPointerType() || QT->isReferenceType())
156  return false;
157 
158  if (const CXXRecordDecl *RD = QT->getAsCXXRecordDecl())
159  return RD->hasAttr<ConsumableAutoCastAttr>();
160 
161  return false;
162 }
163 
164 static bool isSetOnReadPtrType(const QualType &QT) {
165  if (const CXXRecordDecl *RD = QT->getPointeeCXXRecordDecl())
166  return RD->hasAttr<ConsumableSetOnReadAttr>();
167  return false;
168 }
169 
171  switch (State) {
172  case CS_Unconsumed:
173  case CS_Consumed:
174  return true;
175  case CS_None:
176  case CS_Unknown:
177  return false;
178  }
179  llvm_unreachable("invalid enum");
180 }
181 
182 static bool isRValueRef(QualType ParamType) {
183  return ParamType->isRValueReferenceType();
184 }
185 
186 static bool isTestingFunction(const FunctionDecl *FunDecl) {
187  return FunDecl->hasAttr<TestTypestateAttr>();
188 }
189 
190 static bool isPointerOrRef(QualType ParamType) {
191  return ParamType->isPointerType() || ParamType->isReferenceType();
192 }
193 
195  assert(isConsumableType(QT));
196 
197  const ConsumableAttr *CAttr =
198  QT->getAsCXXRecordDecl()->getAttr<ConsumableAttr>();
199 
200  switch (CAttr->getDefaultState()) {
202  return CS_Unknown;
203  case ConsumableAttr::Unconsumed:
204  return CS_Unconsumed;
205  case ConsumableAttr::Consumed:
206  return CS_Consumed;
207  }
208  llvm_unreachable("invalid enum");
209 }
210 
211 static ConsumedState
212 mapParamTypestateAttrState(const ParamTypestateAttr *PTAttr) {
213  switch (PTAttr->getParamState()) {
215  return CS_Unknown;
216  case ParamTypestateAttr::Unconsumed:
217  return CS_Unconsumed;
218  case ParamTypestateAttr::Consumed:
219  return CS_Consumed;
220  }
221  llvm_unreachable("invalid_enum");
222 }
223 
224 static ConsumedState
225 mapReturnTypestateAttrState(const ReturnTypestateAttr *RTSAttr) {
226  switch (RTSAttr->getState()) {
228  return CS_Unknown;
229  case ReturnTypestateAttr::Unconsumed:
230  return CS_Unconsumed;
231  case ReturnTypestateAttr::Consumed:
232  return CS_Consumed;
233  }
234  llvm_unreachable("invalid enum");
235 }
236 
237 static ConsumedState mapSetTypestateAttrState(const SetTypestateAttr *STAttr) {
238  switch (STAttr->getNewState()) {
240  return CS_Unknown;
241  case SetTypestateAttr::Unconsumed:
242  return CS_Unconsumed;
243  case SetTypestateAttr::Consumed:
244  return CS_Consumed;
245  }
246  llvm_unreachable("invalid_enum");
247 }
248 
249 static StringRef stateToString(ConsumedState State) {
250  switch (State) {
251  case consumed::CS_None:
252  return "none";
253 
255  return "unknown";
256 
258  return "unconsumed";
259 
261  return "consumed";
262  }
263  llvm_unreachable("invalid enum");
264 }
265 
266 static ConsumedState testsFor(const FunctionDecl *FunDecl) {
267  assert(isTestingFunction(FunDecl));
268  switch (FunDecl->getAttr<TestTypestateAttr>()->getTestState()) {
269  case TestTypestateAttr::Unconsumed:
270  return CS_Unconsumed;
271  case TestTypestateAttr::Consumed:
272  return CS_Consumed;
273  }
274  llvm_unreachable("invalid enum");
275 }
276 
277 namespace {
278 
279 struct VarTestResult {
280  const VarDecl *Var;
281  ConsumedState TestsFor;
282 };
283 
284 } // namespace
285 
286 namespace clang {
287 namespace consumed {
288 
292 };
293 
295  enum {
296  IT_None,
297  IT_State,
298  IT_VarTest,
299  IT_BinTest,
300  IT_Var,
301  IT_Tmp
302  } InfoType = IT_None;
303 
304  struct BinTestTy {
305  const BinaryOperator *Source;
306  EffectiveOp EOp;
307  VarTestResult LTest;
308  VarTestResult RTest;
309  };
310 
311  union {
313  VarTestResult VarTest;
314  const VarDecl *Var;
316  BinTestTy BinTest;
317  };
318 
319 public:
320  PropagationInfo() = default;
321  PropagationInfo(const VarTestResult &VarTest)
322  : InfoType(IT_VarTest), VarTest(VarTest) {}
323 
324  PropagationInfo(const VarDecl *Var, ConsumedState TestsFor)
325  : InfoType(IT_VarTest) {
326  VarTest.Var = Var;
327  VarTest.TestsFor = TestsFor;
328  }
329 
331  const VarTestResult &LTest, const VarTestResult &RTest)
332  : InfoType(IT_BinTest) {
333  BinTest.Source = Source;
334  BinTest.EOp = EOp;
335  BinTest.LTest = LTest;
336  BinTest.RTest = RTest;
337  }
338 
340  const VarDecl *LVar, ConsumedState LTestsFor,
341  const VarDecl *RVar, ConsumedState RTestsFor)
342  : InfoType(IT_BinTest) {
343  BinTest.Source = Source;
344  BinTest.EOp = EOp;
345  BinTest.LTest.Var = LVar;
346  BinTest.LTest.TestsFor = LTestsFor;
347  BinTest.RTest.Var = RVar;
348  BinTest.RTest.TestsFor = RTestsFor;
349  }
350 
352  : InfoType(IT_State), State(State) {}
353  PropagationInfo(const VarDecl *Var) : InfoType(IT_Var), Var(Var) {}
355  : InfoType(IT_Tmp), Tmp(Tmp) {}
356 
357  const ConsumedState &getState() const {
358  assert(InfoType == IT_State);
359  return State;
360  }
361 
362  const VarTestResult &getVarTest() const {
363  assert(InfoType == IT_VarTest);
364  return VarTest;
365  }
366 
367  const VarTestResult &getLTest() const {
368  assert(InfoType == IT_BinTest);
369  return BinTest.LTest;
370  }
371 
372  const VarTestResult &getRTest() const {
373  assert(InfoType == IT_BinTest);
374  return BinTest.RTest;
375  }
376 
377  const VarDecl *getVar() const {
378  assert(InfoType == IT_Var);
379  return Var;
380  }
381 
382  const CXXBindTemporaryExpr *getTmp() const {
383  assert(InfoType == IT_Tmp);
384  return Tmp;
385  }
386 
387  ConsumedState getAsState(const ConsumedStateMap *StateMap) const {
388  assert(isVar() || isTmp() || isState());
389 
390  if (isVar())
391  return StateMap->getState(Var);
392  else if (isTmp())
393  return StateMap->getState(Tmp);
394  else if (isState())
395  return State;
396  else
397  return CS_None;
398  }
399 
401  assert(InfoType == IT_BinTest);
402  return BinTest.EOp;
403  }
404 
405  const BinaryOperator * testSourceNode() const {
406  assert(InfoType == IT_BinTest);
407  return BinTest.Source;
408  }
409 
410  bool isValid() const { return InfoType != IT_None; }
411  bool isState() const { return InfoType == IT_State; }
412  bool isVarTest() const { return InfoType == IT_VarTest; }
413  bool isBinTest() const { return InfoType == IT_BinTest; }
414  bool isVar() const { return InfoType == IT_Var; }
415  bool isTmp() const { return InfoType == IT_Tmp; }
416 
417  bool isTest() const {
418  return InfoType == IT_VarTest || InfoType == IT_BinTest;
419  }
420 
421  bool isPointerToValue() const {
422  return InfoType == IT_Var || InfoType == IT_Tmp;
423  }
424 
426  assert(InfoType == IT_VarTest || InfoType == IT_BinTest);
427 
428  if (InfoType == IT_VarTest) {
429  return PropagationInfo(VarTest.Var,
430  invertConsumedUnconsumed(VarTest.TestsFor));
431 
432  } else if (InfoType == IT_BinTest) {
433  return PropagationInfo(BinTest.Source,
434  BinTest.EOp == EO_And ? EO_Or : EO_And,
435  BinTest.LTest.Var, invertConsumedUnconsumed(BinTest.LTest.TestsFor),
436  BinTest.RTest.Var, invertConsumedUnconsumed(BinTest.RTest.TestsFor));
437  } else {
438  return {};
439  }
440  }
441 };
442 
443 } // namespace consumed
444 } // namespace clang
445 
446 static void
449  assert(PInfo.isVar() || PInfo.isTmp());
450 
451  if (PInfo.isVar())
452  StateMap->setState(PInfo.getVar(), State);
453  else
454  StateMap->setState(PInfo.getTmp(), State);
455 }
456 
457 namespace clang {
458 namespace consumed {
459 
460 class ConsumedStmtVisitor : public ConstStmtVisitor<ConsumedStmtVisitor> {
461  using MapType = llvm::DenseMap<const Stmt *, PropagationInfo>;
462  using PairType= std::pair<const Stmt *, PropagationInfo>;
463  using InfoEntry = MapType::iterator;
464  using ConstInfoEntry = MapType::const_iterator;
465 
466  ConsumedAnalyzer &Analyzer;
467  ConsumedStateMap *StateMap;
468  MapType PropagationMap;
469 
470  InfoEntry findInfo(const Expr *E) {
471  if (const auto Cleanups = dyn_cast<ExprWithCleanups>(E))
472  if (!Cleanups->cleanupsHaveSideEffects())
473  E = Cleanups->getSubExpr();
474  return PropagationMap.find(E->IgnoreParens());
475  }
476 
477  ConstInfoEntry findInfo(const Expr *E) const {
478  if (const auto Cleanups = dyn_cast<ExprWithCleanups>(E))
479  if (!Cleanups->cleanupsHaveSideEffects())
480  E = Cleanups->getSubExpr();
481  return PropagationMap.find(E->IgnoreParens());
482  }
483 
484  void insertInfo(const Expr *E, const PropagationInfo &PI) {
485  PropagationMap.insert(PairType(E->IgnoreParens(), PI));
486  }
487 
488  void forwardInfo(const Expr *From, const Expr *To);
489  void copyInfo(const Expr *From, const Expr *To, ConsumedState CS);
490  ConsumedState getInfo(const Expr *From);
491  void setInfo(const Expr *To, ConsumedState NS);
492  void propagateReturnType(const Expr *Call, const FunctionDecl *Fun);
493 
494 public:
495  void checkCallability(const PropagationInfo &PInfo,
496  const FunctionDecl *FunDecl,
497  SourceLocation BlameLoc);
498  bool handleCall(const CallExpr *Call, const Expr *ObjArg,
499  const FunctionDecl *FunD);
500 
501  void VisitBinaryOperator(const BinaryOperator *BinOp);
502  void VisitCallExpr(const CallExpr *Call);
503  void VisitCastExpr(const CastExpr *Cast);
504  void VisitCXXBindTemporaryExpr(const CXXBindTemporaryExpr *Temp);
505  void VisitCXXConstructExpr(const CXXConstructExpr *Call);
506  void VisitCXXMemberCallExpr(const CXXMemberCallExpr *Call);
507  void VisitCXXOperatorCallExpr(const CXXOperatorCallExpr *Call);
508  void VisitDeclRefExpr(const DeclRefExpr *DeclRef);
509  void VisitDeclStmt(const DeclStmt *DelcS);
510  void VisitMaterializeTemporaryExpr(const MaterializeTemporaryExpr *Temp);
511  void VisitMemberExpr(const MemberExpr *MExpr);
512  void VisitParmVarDecl(const ParmVarDecl *Param);
513  void VisitReturnStmt(const ReturnStmt *Ret);
514  void VisitUnaryOperator(const UnaryOperator *UOp);
515  void VisitVarDecl(const VarDecl *Var);
516 
518  : Analyzer(Analyzer), StateMap(StateMap) {}
519 
520  PropagationInfo getInfo(const Expr *StmtNode) const {
521  ConstInfoEntry Entry = findInfo(StmtNode);
522 
523  if (Entry != PropagationMap.end())
524  return Entry->second;
525  else
526  return {};
527  }
528 
529  void reset(ConsumedStateMap *NewStateMap) {
530  StateMap = NewStateMap;
531  }
532 };
533 
534 } // namespace consumed
535 } // namespace clang
536 
537 void ConsumedStmtVisitor::forwardInfo(const Expr *From, const Expr *To) {
538  InfoEntry Entry = findInfo(From);
539  if (Entry != PropagationMap.end())
540  insertInfo(To, Entry->second);
541 }
542 
543 // Create a new state for To, which is initialized to the state of From.
544 // If NS is not CS_None, sets the state of From to NS.
545 void ConsumedStmtVisitor::copyInfo(const Expr *From, const Expr *To,
546  ConsumedState NS) {
547  InfoEntry Entry = findInfo(From);
548  if (Entry != PropagationMap.end()) {
549  PropagationInfo& PInfo = Entry->second;
550  ConsumedState CS = PInfo.getAsState(StateMap);
551  if (CS != CS_None)
552  insertInfo(To, PropagationInfo(CS));
553  if (NS != CS_None && PInfo.isPointerToValue())
554  setStateForVarOrTmp(StateMap, PInfo, NS);
555  }
556 }
557 
558 // Get the ConsumedState for From
559 ConsumedState ConsumedStmtVisitor::getInfo(const Expr *From) {
560  InfoEntry Entry = findInfo(From);
561  if (Entry != PropagationMap.end()) {
562  PropagationInfo& PInfo = Entry->second;
563  return PInfo.getAsState(StateMap);
564  }
565  return CS_None;
566 }
567 
568 // If we already have info for To then update it, otherwise create a new entry.
569 void ConsumedStmtVisitor::setInfo(const Expr *To, ConsumedState NS) {
570  InfoEntry Entry = findInfo(To);
571  if (Entry != PropagationMap.end()) {
572  PropagationInfo& PInfo = Entry->second;
573  if (PInfo.isPointerToValue())
574  setStateForVarOrTmp(StateMap, PInfo, NS);
575  } else if (NS != CS_None) {
576  insertInfo(To, PropagationInfo(NS));
577  }
578 }
579 
581  const FunctionDecl *FunDecl,
582  SourceLocation BlameLoc) {
583  assert(!PInfo.isTest());
584 
585  const CallableWhenAttr *CWAttr = FunDecl->getAttr<CallableWhenAttr>();
586  if (!CWAttr)
587  return;
588 
589  if (PInfo.isVar()) {
590  ConsumedState VarState = StateMap->getState(PInfo.getVar());
591 
592  if (VarState == CS_None || isCallableInState(CWAttr, VarState))
593  return;
594 
595  Analyzer.WarningsHandler.warnUseInInvalidState(
596  FunDecl->getNameAsString(), PInfo.getVar()->getNameAsString(),
597  stateToString(VarState), BlameLoc);
598  } else {
599  ConsumedState TmpState = PInfo.getAsState(StateMap);
600 
601  if (TmpState == CS_None || isCallableInState(CWAttr, TmpState))
602  return;
603 
604  Analyzer.WarningsHandler.warnUseOfTempInInvalidState(
605  FunDecl->getNameAsString(), stateToString(TmpState), BlameLoc);
606  }
607 }
608 
609 // Factors out common behavior for function, method, and operator calls.
610 // Check parameters and set parameter state if necessary.
611 // Returns true if the state of ObjArg is set, or false otherwise.
612 bool ConsumedStmtVisitor::handleCall(const CallExpr *Call, const Expr *ObjArg,
613  const FunctionDecl *FunD) {
614  unsigned Offset = 0;
615  if (isa<CXXOperatorCallExpr>(Call) && isa<CXXMethodDecl>(FunD))
616  Offset = 1; // first argument is 'this'
617 
618  // check explicit parameters
619  for (unsigned Index = Offset; Index < Call->getNumArgs(); ++Index) {
620  // Skip variable argument lists.
621  if (Index - Offset >= FunD->getNumParams())
622  break;
623 
624  const ParmVarDecl *Param = FunD->getParamDecl(Index - Offset);
625  QualType ParamType = Param->getType();
626 
627  InfoEntry Entry = findInfo(Call->getArg(Index));
628 
629  if (Entry == PropagationMap.end() || Entry->second.isTest())
630  continue;
631  PropagationInfo PInfo = Entry->second;
632 
633  // Check that the parameter is in the correct state.
634  if (ParamTypestateAttr *PTA = Param->getAttr<ParamTypestateAttr>()) {
635  ConsumedState ParamState = PInfo.getAsState(StateMap);
636  ConsumedState ExpectedState = mapParamTypestateAttrState(PTA);
637 
638  if (ParamState != ExpectedState)
639  Analyzer.WarningsHandler.warnParamTypestateMismatch(
640  Call->getArg(Index)->getExprLoc(),
641  stateToString(ExpectedState), stateToString(ParamState));
642  }
643 
644  if (!(Entry->second.isVar() || Entry->second.isTmp()))
645  continue;
646 
647  // Adjust state on the caller side.
648  if (isRValueRef(ParamType))
649  setStateForVarOrTmp(StateMap, PInfo, consumed::CS_Consumed);
650  else if (ReturnTypestateAttr *RT = Param->getAttr<ReturnTypestateAttr>())
651  setStateForVarOrTmp(StateMap, PInfo, mapReturnTypestateAttrState(RT));
652  else if (isPointerOrRef(ParamType) &&
653  (!ParamType->getPointeeType().isConstQualified() ||
654  isSetOnReadPtrType(ParamType)))
655  setStateForVarOrTmp(StateMap, PInfo, consumed::CS_Unknown);
656  }
657 
658  if (!ObjArg)
659  return false;
660 
661  // check implicit 'self' parameter, if present
662  InfoEntry Entry = findInfo(ObjArg);
663  if (Entry != PropagationMap.end()) {
664  PropagationInfo PInfo = Entry->second;
665  checkCallability(PInfo, FunD, Call->getExprLoc());
666 
667  if (SetTypestateAttr *STA = FunD->getAttr<SetTypestateAttr>()) {
668  if (PInfo.isVar()) {
669  StateMap->setState(PInfo.getVar(), mapSetTypestateAttrState(STA));
670  return true;
671  }
672  else if (PInfo.isTmp()) {
673  StateMap->setState(PInfo.getTmp(), mapSetTypestateAttrState(STA));
674  return true;
675  }
676  }
677  else if (isTestingFunction(FunD) && PInfo.isVar()) {
678  PropagationMap.insert(PairType(Call,
679  PropagationInfo(PInfo.getVar(), testsFor(FunD))));
680  }
681  }
682  return false;
683 }
684 
685 void ConsumedStmtVisitor::propagateReturnType(const Expr *Call,
686  const FunctionDecl *Fun) {
687  QualType RetType = Fun->getCallResultType();
688  if (RetType->isReferenceType())
689  RetType = RetType->getPointeeType();
690 
691  if (isConsumableType(RetType)) {
692  ConsumedState ReturnState;
693  if (ReturnTypestateAttr *RTA = Fun->getAttr<ReturnTypestateAttr>())
694  ReturnState = mapReturnTypestateAttrState(RTA);
695  else
696  ReturnState = mapConsumableAttrState(RetType);
697 
698  PropagationMap.insert(PairType(Call, PropagationInfo(ReturnState)));
699  }
700 }
701 
703  switch (BinOp->getOpcode()) {
704  case BO_LAnd:
705  case BO_LOr : {
706  InfoEntry LEntry = findInfo(BinOp->getLHS()),
707  REntry = findInfo(BinOp->getRHS());
708 
709  VarTestResult LTest, RTest;
710 
711  if (LEntry != PropagationMap.end() && LEntry->second.isVarTest()) {
712  LTest = LEntry->second.getVarTest();
713  } else {
714  LTest.Var = nullptr;
715  LTest.TestsFor = CS_None;
716  }
717 
718  if (REntry != PropagationMap.end() && REntry->second.isVarTest()) {
719  RTest = REntry->second.getVarTest();
720  } else {
721  RTest.Var = nullptr;
722  RTest.TestsFor = CS_None;
723  }
724 
725  if (!(LTest.Var == nullptr && RTest.Var == nullptr))
726  PropagationMap.insert(PairType(BinOp, PropagationInfo(BinOp,
727  static_cast<EffectiveOp>(BinOp->getOpcode() == BO_LOr), LTest, RTest)));
728  break;
729  }
730 
731  case BO_PtrMemD:
732  case BO_PtrMemI:
733  forwardInfo(BinOp->getLHS(), BinOp);
734  break;
735 
736  default:
737  break;
738  }
739 }
740 
742  const FunctionDecl *FunDecl = Call->getDirectCallee();
743  if (!FunDecl)
744  return;
745 
746  // Special case for the std::move function.
747  // TODO: Make this more specific. (Deferred)
748  if (Call->isCallToStdMove()) {
749  copyInfo(Call->getArg(0), Call, CS_Consumed);
750  return;
751  }
752 
753  handleCall(Call, nullptr, FunDecl);
754  propagateReturnType(Call, FunDecl);
755 }
756 
758  forwardInfo(Cast->getSubExpr(), Cast);
759 }
760 
762  const CXXBindTemporaryExpr *Temp) {
763 
764  InfoEntry Entry = findInfo(Temp->getSubExpr());
765 
766  if (Entry != PropagationMap.end() && !Entry->second.isTest()) {
767  StateMap->setState(Temp, Entry->second.getAsState(StateMap));
768  PropagationMap.insert(PairType(Temp, PropagationInfo(Temp)));
769  }
770 }
771 
773  CXXConstructorDecl *Constructor = Call->getConstructor();
774 
775  QualType ThisType = Constructor->getThisType()->getPointeeType();
776 
777  if (!isConsumableType(ThisType))
778  return;
779 
780  // FIXME: What should happen if someone annotates the move constructor?
781  if (ReturnTypestateAttr *RTA = Constructor->getAttr<ReturnTypestateAttr>()) {
782  // TODO: Adjust state of args appropriately.
784  PropagationMap.insert(PairType(Call, PropagationInfo(RetState)));
785  } else if (Constructor->isDefaultConstructor()) {
786  PropagationMap.insert(PairType(Call,
788  } else if (Constructor->isMoveConstructor()) {
789  copyInfo(Call->getArg(0), Call, CS_Consumed);
790  } else if (Constructor->isCopyConstructor()) {
791  // Copy state from arg. If setStateOnRead then set arg to CS_Unknown.
792  ConsumedState NS =
793  isSetOnReadPtrType(Constructor->getThisType()) ?
795  copyInfo(Call->getArg(0), Call, NS);
796  } else {
797  // TODO: Adjust state of args appropriately.
798  ConsumedState RetState = mapConsumableAttrState(ThisType);
799  PropagationMap.insert(PairType(Call, PropagationInfo(RetState)));
800  }
801 }
802 
804  const CXXMemberCallExpr *Call) {
805  CXXMethodDecl* MD = Call->getMethodDecl();
806  if (!MD)
807  return;
808 
809  handleCall(Call, Call->getImplicitObjectArgument(), MD);
810  propagateReturnType(Call, MD);
811 }
812 
814  const CXXOperatorCallExpr *Call) {
815  const auto *FunDecl = dyn_cast_or_null<FunctionDecl>(Call->getDirectCallee());
816  if (!FunDecl) return;
817 
818  if (Call->getOperator() == OO_Equal) {
819  ConsumedState CS = getInfo(Call->getArg(1));
820  if (!handleCall(Call, Call->getArg(0), FunDecl))
821  setInfo(Call->getArg(0), CS);
822  return;
823  }
824 
825  if (const auto *MCall = dyn_cast<CXXMemberCallExpr>(Call))
826  handleCall(MCall, MCall->getImplicitObjectArgument(), FunDecl);
827  else
828  handleCall(Call, Call->getArg(0), FunDecl);
829 
830  propagateReturnType(Call, FunDecl);
831 }
832 
834  if (const auto *Var = dyn_cast_or_null<VarDecl>(DeclRef->getDecl()))
835  if (StateMap->getState(Var) != consumed::CS_None)
836  PropagationMap.insert(PairType(DeclRef, PropagationInfo(Var)));
837 }
838 
840  for (const auto *DI : DeclS->decls())
841  if (isa<VarDecl>(DI))
842  VisitVarDecl(cast<VarDecl>(DI));
843 
844  if (DeclS->isSingleDecl())
845  if (const auto *Var = dyn_cast_or_null<VarDecl>(DeclS->getSingleDecl()))
846  PropagationMap.insert(PairType(DeclS, PropagationInfo(Var)));
847 }
848 
850  const MaterializeTemporaryExpr *Temp) {
851  forwardInfo(Temp->GetTemporaryExpr(), Temp);
852 }
853 
855  forwardInfo(MExpr->getBase(), MExpr);
856 }
857 
859  QualType ParamType = Param->getType();
860  ConsumedState ParamState = consumed::CS_None;
861 
862  if (const ParamTypestateAttr *PTA = Param->getAttr<ParamTypestateAttr>())
863  ParamState = mapParamTypestateAttrState(PTA);
864  else if (isConsumableType(ParamType))
865  ParamState = mapConsumableAttrState(ParamType);
866  else if (isRValueRef(ParamType) &&
867  isConsumableType(ParamType->getPointeeType()))
868  ParamState = mapConsumableAttrState(ParamType->getPointeeType());
869  else if (ParamType->isReferenceType() &&
870  isConsumableType(ParamType->getPointeeType()))
871  ParamState = consumed::CS_Unknown;
872 
873  if (ParamState != CS_None)
874  StateMap->setState(Param, ParamState);
875 }
876 
878  ConsumedState ExpectedState = Analyzer.getExpectedReturnState();
879 
880  if (ExpectedState != CS_None) {
881  InfoEntry Entry = findInfo(Ret->getRetValue());
882 
883  if (Entry != PropagationMap.end()) {
884  ConsumedState RetState = Entry->second.getAsState(StateMap);
885 
886  if (RetState != ExpectedState)
887  Analyzer.WarningsHandler.warnReturnTypestateMismatch(
888  Ret->getReturnLoc(), stateToString(ExpectedState),
889  stateToString(RetState));
890  }
891  }
892 
893  StateMap->checkParamsForReturnTypestate(Ret->getBeginLoc(),
894  Analyzer.WarningsHandler);
895 }
896 
898  InfoEntry Entry = findInfo(UOp->getSubExpr());
899  if (Entry == PropagationMap.end()) return;
900 
901  switch (UOp->getOpcode()) {
902  case UO_AddrOf:
903  PropagationMap.insert(PairType(UOp, Entry->second));
904  break;
905 
906  case UO_LNot:
907  if (Entry->second.isTest())
908  PropagationMap.insert(PairType(UOp, Entry->second.invertTest()));
909  break;
910 
911  default:
912  break;
913  }
914 }
915 
916 // TODO: See if I need to check for reference types here.
918  if (isConsumableType(Var->getType())) {
919  if (Var->hasInit()) {
920  MapType::iterator VIT = findInfo(Var->getInit()->IgnoreImplicit());
921  if (VIT != PropagationMap.end()) {
922  PropagationInfo PInfo = VIT->second;
923  ConsumedState St = PInfo.getAsState(StateMap);
924 
925  if (St != consumed::CS_None) {
926  StateMap->setState(Var, St);
927  return;
928  }
929  }
930  }
931  // Otherwise
932  StateMap->setState(Var, consumed::CS_Unknown);
933  }
934 }
935 
936 static void splitVarStateForIf(const IfStmt *IfNode, const VarTestResult &Test,
937  ConsumedStateMap *ThenStates,
938  ConsumedStateMap *ElseStates) {
939  ConsumedState VarState = ThenStates->getState(Test.Var);
940 
941  if (VarState == CS_Unknown) {
942  ThenStates->setState(Test.Var, Test.TestsFor);
943  ElseStates->setState(Test.Var, invertConsumedUnconsumed(Test.TestsFor));
944  } else if (VarState == invertConsumedUnconsumed(Test.TestsFor)) {
945  ThenStates->markUnreachable();
946  } else if (VarState == Test.TestsFor) {
947  ElseStates->markUnreachable();
948  }
949 }
950 
951 static void splitVarStateForIfBinOp(const PropagationInfo &PInfo,
952  ConsumedStateMap *ThenStates,
953  ConsumedStateMap *ElseStates) {
954  const VarTestResult &LTest = PInfo.getLTest(),
955  &RTest = PInfo.getRTest();
956 
957  ConsumedState LState = LTest.Var ? ThenStates->getState(LTest.Var) : CS_None,
958  RState = RTest.Var ? ThenStates->getState(RTest.Var) : CS_None;
959 
960  if (LTest.Var) {
961  if (PInfo.testEffectiveOp() == EO_And) {
962  if (LState == CS_Unknown) {
963  ThenStates->setState(LTest.Var, LTest.TestsFor);
964  } else if (LState == invertConsumedUnconsumed(LTest.TestsFor)) {
965  ThenStates->markUnreachable();
966  } else if (LState == LTest.TestsFor && isKnownState(RState)) {
967  if (RState == RTest.TestsFor)
968  ElseStates->markUnreachable();
969  else
970  ThenStates->markUnreachable();
971  }
972  } else {
973  if (LState == CS_Unknown) {
974  ElseStates->setState(LTest.Var,
975  invertConsumedUnconsumed(LTest.TestsFor));
976  } else if (LState == LTest.TestsFor) {
977  ElseStates->markUnreachable();
978  } else if (LState == invertConsumedUnconsumed(LTest.TestsFor) &&
979  isKnownState(RState)) {
980  if (RState == RTest.TestsFor)
981  ElseStates->markUnreachable();
982  else
983  ThenStates->markUnreachable();
984  }
985  }
986  }
987 
988  if (RTest.Var) {
989  if (PInfo.testEffectiveOp() == EO_And) {
990  if (RState == CS_Unknown)
991  ThenStates->setState(RTest.Var, RTest.TestsFor);
992  else if (RState == invertConsumedUnconsumed(RTest.TestsFor))
993  ThenStates->markUnreachable();
994  } else {
995  if (RState == CS_Unknown)
996  ElseStates->setState(RTest.Var,
997  invertConsumedUnconsumed(RTest.TestsFor));
998  else if (RState == RTest.TestsFor)
999  ElseStates->markUnreachable();
1000  }
1001  }
1002 }
1003 
1005  const CFGBlock *TargetBlock) {
1006  assert(CurrBlock && "Block pointer must not be NULL");
1007  assert(TargetBlock && "TargetBlock pointer must not be NULL");
1008 
1009  unsigned int CurrBlockOrder = VisitOrder[CurrBlock->getBlockID()];
1010  for (CFGBlock::const_pred_iterator PI = TargetBlock->pred_begin(),
1011  PE = TargetBlock->pred_end(); PI != PE; ++PI) {
1012  if (*PI && CurrBlockOrder < VisitOrder[(*PI)->getBlockID()] )
1013  return false;
1014  }
1015  return true;
1016 }
1017 
1019  const CFGBlock *Block, ConsumedStateMap *StateMap,
1020  std::unique_ptr<ConsumedStateMap> &OwnedStateMap) {
1021  assert(Block && "Block pointer must not be NULL");
1022 
1023  auto &Entry = StateMapsArray[Block->getBlockID()];
1024 
1025  if (Entry) {
1026  Entry->intersect(*StateMap);
1027  } else if (OwnedStateMap)
1028  Entry = std::move(OwnedStateMap);
1029  else
1030  Entry = llvm::make_unique<ConsumedStateMap>(*StateMap);
1031 }
1032 
1034  std::unique_ptr<ConsumedStateMap> StateMap) {
1035  assert(Block && "Block pointer must not be NULL");
1036 
1037  auto &Entry = StateMapsArray[Block->getBlockID()];
1038 
1039  if (Entry) {
1040  Entry->intersect(*StateMap);
1041  } else {
1042  Entry = std::move(StateMap);
1043  }
1044 }
1045 
1047  assert(Block && "Block pointer must not be NULL");
1048  assert(StateMapsArray[Block->getBlockID()] && "Block has no block info");
1049 
1050  return StateMapsArray[Block->getBlockID()].get();
1051 }
1052 
1054  StateMapsArray[Block->getBlockID()] = nullptr;
1055 }
1056 
1057 std::unique_ptr<ConsumedStateMap>
1059  assert(Block && "Block pointer must not be NULL");
1060 
1061  auto &Entry = StateMapsArray[Block->getBlockID()];
1062  return isBackEdgeTarget(Block) ? llvm::make_unique<ConsumedStateMap>(*Entry)
1063  : std::move(Entry);
1064 }
1065 
1066 bool ConsumedBlockInfo::isBackEdge(const CFGBlock *From, const CFGBlock *To) {
1067  assert(From && "From block must not be NULL");
1068  assert(To && "From block must not be NULL");
1069 
1070  return VisitOrder[From->getBlockID()] > VisitOrder[To->getBlockID()];
1071 }
1072 
1074  assert(Block && "Block pointer must not be NULL");
1075 
1076  // Anything with less than two predecessors can't be the target of a back
1077  // edge.
1078  if (Block->pred_size() < 2)
1079  return false;
1080 
1081  unsigned int BlockVisitOrder = VisitOrder[Block->getBlockID()];
1082  for (CFGBlock::const_pred_iterator PI = Block->pred_begin(),
1083  PE = Block->pred_end(); PI != PE; ++PI) {
1084  if (*PI && BlockVisitOrder < VisitOrder[(*PI)->getBlockID()])
1085  return true;
1086  }
1087  return false;
1088 }
1089 
1091  ConsumedWarningsHandlerBase &WarningsHandler) const {
1092 
1093  for (const auto &DM : VarMap) {
1094  if (isa<ParmVarDecl>(DM.first)) {
1095  const auto *Param = cast<ParmVarDecl>(DM.first);
1096  const ReturnTypestateAttr *RTA = Param->getAttr<ReturnTypestateAttr>();
1097 
1098  if (!RTA)
1099  continue;
1100 
1101  ConsumedState ExpectedState = mapReturnTypestateAttrState(RTA);
1102  if (DM.second != ExpectedState)
1103  WarningsHandler.warnParamReturnTypestateMismatch(BlameLoc,
1104  Param->getNameAsString(), stateToString(ExpectedState),
1105  stateToString(DM.second));
1106  }
1107  }
1108 }
1109 
1111  TmpMap.clear();
1112 }
1113 
1115  VarMapType::const_iterator Entry = VarMap.find(Var);
1116 
1117  if (Entry != VarMap.end())
1118  return Entry->second;
1119 
1120  return CS_None;
1121 }
1122 
1125  TmpMapType::const_iterator Entry = TmpMap.find(Tmp);
1126 
1127  if (Entry != TmpMap.end())
1128  return Entry->second;
1129 
1130  return CS_None;
1131 }
1132 
1134  ConsumedState LocalState;
1135 
1136  if (this->From && this->From == Other.From && !Other.Reachable) {
1137  this->markUnreachable();
1138  return;
1139  }
1140 
1141  for (const auto &DM : Other.VarMap) {
1142  LocalState = this->getState(DM.first);
1143 
1144  if (LocalState == CS_None)
1145  continue;
1146 
1147  if (LocalState != DM.second)
1148  VarMap[DM.first] = CS_Unknown;
1149  }
1150 }
1151 
1153  const CFGBlock *LoopBack, const ConsumedStateMap *LoopBackStates,
1154  ConsumedWarningsHandlerBase &WarningsHandler) {
1155 
1156  ConsumedState LocalState;
1157  SourceLocation BlameLoc = getLastStmtLoc(LoopBack);
1158 
1159  for (const auto &DM : LoopBackStates->VarMap) {
1160  LocalState = this->getState(DM.first);
1161 
1162  if (LocalState == CS_None)
1163  continue;
1164 
1165  if (LocalState != DM.second) {
1166  VarMap[DM.first] = CS_Unknown;
1167  WarningsHandler.warnLoopStateMismatch(BlameLoc,
1168  DM.first->getNameAsString());
1169  }
1170  }
1171 }
1172 
1174  this->Reachable = false;
1175  VarMap.clear();
1176  TmpMap.clear();
1177 }
1178 
1180  VarMap[Var] = State;
1181 }
1182 
1184  ConsumedState State) {
1185  TmpMap[Tmp] = State;
1186 }
1187 
1189  TmpMap.erase(Tmp);
1190 }
1191 
1193  for (const auto &DM : Other->VarMap)
1194  if (this->getState(DM.first) != DM.second)
1195  return true;
1196  return false;
1197 }
1198 
1199 void ConsumedAnalyzer::determineExpectedReturnState(AnalysisDeclContext &AC,
1200  const FunctionDecl *D) {
1201  QualType ReturnType;
1202  if (const auto *Constructor = dyn_cast<CXXConstructorDecl>(D)) {
1203  ReturnType = Constructor->getThisType()->getPointeeType();
1204  } else
1205  ReturnType = D->getCallResultType();
1206 
1207  if (const ReturnTypestateAttr *RTSAttr = D->getAttr<ReturnTypestateAttr>()) {
1208  const CXXRecordDecl *RD = ReturnType->getAsCXXRecordDecl();
1209  if (!RD || !RD->hasAttr<ConsumableAttr>()) {
1210  // FIXME: This should be removed when template instantiation propagates
1211  // attributes at template specialization definition, not
1212  // declaration. When it is removed the test needs to be enabled
1213  // in SemaDeclAttr.cpp.
1214  WarningsHandler.warnReturnTypestateForUnconsumableType(
1215  RTSAttr->getLocation(), ReturnType.getAsString());
1216  ExpectedReturnState = CS_None;
1217  } else
1218  ExpectedReturnState = mapReturnTypestateAttrState(RTSAttr);
1219  } else if (isConsumableType(ReturnType)) {
1220  if (isAutoCastType(ReturnType)) // We can auto-cast the state to the
1221  ExpectedReturnState = CS_None; // expected state.
1222  else
1223  ExpectedReturnState = mapConsumableAttrState(ReturnType);
1224  }
1225  else
1226  ExpectedReturnState = CS_None;
1227 }
1228 
1229 bool ConsumedAnalyzer::splitState(const CFGBlock *CurrBlock,
1230  const ConsumedStmtVisitor &Visitor) {
1231  std::unique_ptr<ConsumedStateMap> FalseStates(
1232  new ConsumedStateMap(*CurrStates));
1233  PropagationInfo PInfo;
1234 
1235  if (const auto *IfNode =
1236  dyn_cast_or_null<IfStmt>(CurrBlock->getTerminator().getStmt())) {
1237  const Expr *Cond = IfNode->getCond();
1238 
1239  PInfo = Visitor.getInfo(Cond);
1240  if (!PInfo.isValid() && isa<BinaryOperator>(Cond))
1241  PInfo = Visitor.getInfo(cast<BinaryOperator>(Cond)->getRHS());
1242 
1243  if (PInfo.isVarTest()) {
1244  CurrStates->setSource(Cond);
1245  FalseStates->setSource(Cond);
1246  splitVarStateForIf(IfNode, PInfo.getVarTest(), CurrStates.get(),
1247  FalseStates.get());
1248  } else if (PInfo.isBinTest()) {
1249  CurrStates->setSource(PInfo.testSourceNode());
1250  FalseStates->setSource(PInfo.testSourceNode());
1251  splitVarStateForIfBinOp(PInfo, CurrStates.get(), FalseStates.get());
1252  } else {
1253  return false;
1254  }
1255  } else if (const auto *BinOp =
1256  dyn_cast_or_null<BinaryOperator>(CurrBlock->getTerminator().getStmt())) {
1257  PInfo = Visitor.getInfo(BinOp->getLHS());
1258  if (!PInfo.isVarTest()) {
1259  if ((BinOp = dyn_cast_or_null<BinaryOperator>(BinOp->getLHS()))) {
1260  PInfo = Visitor.getInfo(BinOp->getRHS());
1261 
1262  if (!PInfo.isVarTest())
1263  return false;
1264  } else {
1265  return false;
1266  }
1267  }
1268 
1269  CurrStates->setSource(BinOp);
1270  FalseStates->setSource(BinOp);
1271 
1272  const VarTestResult &Test = PInfo.getVarTest();
1273  ConsumedState VarState = CurrStates->getState(Test.Var);
1274 
1275  if (BinOp->getOpcode() == BO_LAnd) {
1276  if (VarState == CS_Unknown)
1277  CurrStates->setState(Test.Var, Test.TestsFor);
1278  else if (VarState == invertConsumedUnconsumed(Test.TestsFor))
1279  CurrStates->markUnreachable();
1280 
1281  } else if (BinOp->getOpcode() == BO_LOr) {
1282  if (VarState == CS_Unknown)
1283  FalseStates->setState(Test.Var,
1284  invertConsumedUnconsumed(Test.TestsFor));
1285  else if (VarState == Test.TestsFor)
1286  FalseStates->markUnreachable();
1287  }
1288  } else {
1289  return false;
1290  }
1291 
1292  CFGBlock::const_succ_iterator SI = CurrBlock->succ_begin();
1293 
1294  if (*SI)
1295  BlockInfo.addInfo(*SI, std::move(CurrStates));
1296  else
1297  CurrStates = nullptr;
1298 
1299  if (*++SI)
1300  BlockInfo.addInfo(*SI, std::move(FalseStates));
1301 
1302  return true;
1303 }
1304 
1306  const auto *D = dyn_cast_or_null<FunctionDecl>(AC.getDecl());
1307  if (!D)
1308  return;
1309 
1310  CFG *CFGraph = AC.getCFG();
1311  if (!CFGraph)
1312  return;
1313 
1314  determineExpectedReturnState(AC, D);
1315 
1316  PostOrderCFGView *SortedGraph = AC.getAnalysis<PostOrderCFGView>();
1317  // AC.getCFG()->viewCFG(LangOptions());
1318 
1319  BlockInfo = ConsumedBlockInfo(CFGraph->getNumBlockIDs(), SortedGraph);
1320 
1321  CurrStates = llvm::make_unique<ConsumedStateMap>();
1322  ConsumedStmtVisitor Visitor(*this, CurrStates.get());
1323 
1324  // Add all trackable parameters to the state map.
1325  for (const auto *PI : D->parameters())
1326  Visitor.VisitParmVarDecl(PI);
1327 
1328  // Visit all of the function's basic blocks.
1329  for (const auto *CurrBlock : *SortedGraph) {
1330  if (!CurrStates)
1331  CurrStates = BlockInfo.getInfo(CurrBlock);
1332 
1333  if (!CurrStates) {
1334  continue;
1335  } else if (!CurrStates->isReachable()) {
1336  CurrStates = nullptr;
1337  continue;
1338  }
1339 
1340  Visitor.reset(CurrStates.get());
1341 
1342  // Visit all of the basic block's statements.
1343  for (const auto &B : *CurrBlock) {
1344  switch (B.getKind()) {
1345  case CFGElement::Statement:
1346  Visitor.Visit(B.castAs<CFGStmt>().getStmt());
1347  break;
1348 
1350  const CFGTemporaryDtor &DTor = B.castAs<CFGTemporaryDtor>();
1351  const CXXBindTemporaryExpr *BTE = DTor.getBindTemporaryExpr();
1352 
1353  Visitor.checkCallability(PropagationInfo(BTE),
1354  DTor.getDestructorDecl(AC.getASTContext()),
1355  BTE->getExprLoc());
1356  CurrStates->remove(BTE);
1357  break;
1358  }
1359 
1361  const CFGAutomaticObjDtor &DTor = B.castAs<CFGAutomaticObjDtor>();
1362  SourceLocation Loc = DTor.getTriggerStmt()->getEndLoc();
1363  const VarDecl *Var = DTor.getVarDecl();
1364 
1365  Visitor.checkCallability(PropagationInfo(Var),
1366  DTor.getDestructorDecl(AC.getASTContext()),
1367  Loc);
1368  break;
1369  }
1370 
1371  default:
1372  break;
1373  }
1374  }
1375 
1376  // TODO: Handle other forms of branching with precision, including while-
1377  // and for-loops. (Deferred)
1378  if (!splitState(CurrBlock, Visitor)) {
1379  CurrStates->setSource(nullptr);
1380 
1381  if (CurrBlock->succ_size() > 1 ||
1382  (CurrBlock->succ_size() == 1 &&
1383  (*CurrBlock->succ_begin())->pred_size() > 1)) {
1384 
1385  auto *RawState = CurrStates.get();
1386 
1387  for (CFGBlock::const_succ_iterator SI = CurrBlock->succ_begin(),
1388  SE = CurrBlock->succ_end(); SI != SE; ++SI) {
1389  if (*SI == nullptr) continue;
1390 
1391  if (BlockInfo.isBackEdge(CurrBlock, *SI)) {
1392  BlockInfo.borrowInfo(*SI)->intersectAtLoopHead(
1393  *SI, CurrBlock, RawState, WarningsHandler);
1394 
1395  if (BlockInfo.allBackEdgesVisited(CurrBlock, *SI))
1396  BlockInfo.discardInfo(*SI);
1397  } else {
1398  BlockInfo.addInfo(*SI, RawState, CurrStates);
1399  }
1400  }
1401 
1402  CurrStates = nullptr;
1403  }
1404  }
1405 
1406  if (CurrBlock == &AC.getCFG()->getExit() &&
1407  D->getCallResultType()->isVoidType())
1408  CurrStates->checkParamsForReturnTypestate(D->getLocation(),
1409  WarningsHandler);
1410  } // End of block iterator.
1411 
1412  // Delete the last existing state map.
1413  CurrStates = nullptr;
1414 
1415  WarningsHandler.emitDiagnostics();
1416 }
void VisitDeclStmt(const DeclStmt *DelcS)
Definition: Consumed.cpp:839
A call to an overloaded operator written using operator syntax.
Definition: ExprCXX.h:78
bool isCallToStdMove() const
Definition: Expr.h:2645
Represents a function declaration or definition.
Definition: Decl.h:1738
const ConsumedState & getState() const
Definition: Consumed.cpp:357
SourceLocation getBeginLoc() const
Definition: Stmt.h:2502
pred_iterator pred_end()
Definition: CFG.h:734
A (possibly-)qualified type.
Definition: Type.h:638
Expr * getArg(unsigned Arg)
getArg - Return the specified argument.
Definition: Expr.h:2553
AdjacentBlocks::const_iterator const_pred_iterator
Definition: CFG.h:720
const Stmt * getStmt() const
Definition: CFG.h:133
ConstStmtVisitor - This class implements a simple visitor for Stmt subclasses.
Definition: StmtVisitor.h:193
succ_iterator succ_begin()
Definition: CFG.h:751
Stmt - This represents one statement.
Definition: Stmt.h:66
unsigned getNumArgs() const
getNumArgs - Return the number of actual arguments to this call.
Definition: Expr.h:2540
IfStmt - This represents an if/then/else.
Definition: Stmt.h:1687
QualType getPointeeType() const
If this is a pointer, ObjC object pointer, or block pointer, this returns the respective pointee...
Definition: Type.cpp:505
C Language Family Type Representation.
QualType getThisType() const
Returns the type of the this pointer.
Definition: DeclCXX.cpp:2184
Expr * getBase() const
Definition: Expr.h:2767
unsigned getBlockID() const
Definition: CFG.h:856
Expr * getImplicitObjectArgument() const
Retrieves the implicit object argument for the member call.
Definition: ExprCXX.cpp:640
virtual void warnParamReturnTypestateMismatch(SourceLocation Loc, StringRef VariableName, StringRef ExpectedState, StringRef ObservedState)
Warn about parameter typestate mismatches upon return.
Definition: Consumed.h:83
Opcode getOpcode() const
Definition: Expr.h:3322
Represents a call to a C++ constructor.
Definition: ExprCXX.h:1262
QualType getCallResultType() const
Determine the type of an expression that calls this function.
Definition: Decl.h:2324
T castAs() const
Convert to the specified CFGElement type, asserting that this CFGElement is of the desired type...
Definition: CFG.h:99
bool isBackEdge(const CFGBlock *From, const CFGBlock *To)
Definition: Consumed.cpp:1066
Represents a C++ constructor within a class.
Definition: DeclCXX.h:2484
Represents a prvalue temporary that is written into memory so that a reference can bind to it...
Definition: ExprCXX.h:4156
static ConsumedState testsFor(const FunctionDecl *FunDecl)
Definition: Consumed.cpp:266
unsigned succ_size() const
Definition: CFG.h:769
const CXXDestructorDecl * getDestructorDecl(ASTContext &astContext) const
Definition: CFG.cpp:4672
bool isDefaultConstructor() const
Whether this constructor is a default constructor (C++ [class.ctor]p5), which can be used to default-...
Definition: DeclCXX.cpp:2356
void VisitBinaryOperator(const BinaryOperator *BinOp)
Definition: Consumed.cpp:702
Represents a variable declaration or definition.
Definition: Decl.h:813
ASTContext & getASTContext() const
static void splitVarStateForIf(const IfStmt *IfNode, const VarTestResult &Test, ConsumedStateMap *ThenStates, ConsumedStateMap *ElseStates)
Definition: Consumed.cpp:936
Expr * IgnoreImplicit() LLVM_READONLY
IgnoreImplicit - Skip past any implicit AST nodes which might surround this expression.
Definition: Expr.h:747
const CXXBindTemporaryExpr * getTmp() const
Definition: Consumed.cpp:382
const Stmt * getTriggerStmt() const
Definition: CFG.h:394
void VisitParmVarDecl(const ParmVarDecl *Param)
Definition: Consumed.cpp:858
Represents a parameter to a function.
Definition: Decl.h:1550
Defines the clang::Expr interface and subclasses for C++ expressions.
PropagationInfo(const VarTestResult &VarTest)
Definition: Consumed.cpp:321
PropagationInfo(const VarDecl *Var)
Definition: Consumed.cpp:353
Expr * GetTemporaryExpr() const
Retrieve the temporary-generating subexpression whose value will be materialized into a glvalue...
Definition: ExprCXX.h:4197
LineState State
ConsumedState getState(const VarDecl *Var) const
Get the consumed state of a given variable.
Definition: Consumed.cpp:1114
AnalysisDeclContext contains the context data for the function or method under analysis.
Represents C++ object destructor implicitly generated for automatic object or temporary bound to cons...
Definition: CFG.h:384
const BinaryOperator * testSourceNode() const
Definition: Consumed.cpp:405
const VarTestResult & getRTest() const
Definition: Consumed.cpp:372
bool isReferenceType() const
Definition: Type.h:6311
PropagationInfo(const BinaryOperator *Source, EffectiveOp EOp, const VarDecl *LVar, ConsumedState LTestsFor, const VarDecl *RVar, ConsumedState RTestsFor)
Definition: Consumed.cpp:339
PropagationInfo(const CXXBindTemporaryExpr *Tmp)
Definition: Consumed.cpp:354
static ConsumedState mapReturnTypestateAttrState(const ReturnTypestateAttr *RTSAttr)
Definition: Consumed.cpp:225
Expr * getSubExpr()
Definition: Expr.h:3050
ArrayRef< ParmVarDecl * > parameters() const
Definition: Decl.h:2262
AdjacentBlocks::const_iterator const_succ_iterator
Definition: CFG.h:727
EffectiveOp testEffectiveOp() const
Definition: Consumed.cpp:400
bool operator!=(const ConsumedStateMap *Other) const
Tests to see if there is a mismatch in the states stored in two maps.
Definition: Consumed.cpp:1192
Forward-declares and imports various common LLVM datatypes that clang wants to use unqualified...
ConsumedStmtVisitor(ConsumedAnalyzer &Analyzer, ConsumedStateMap *StateMap)
Definition: Consumed.cpp:517
void intersectAtLoopHead(const CFGBlock *LoopHead, const CFGBlock *LoopBack, const ConsumedStateMap *LoopBackStates, ConsumedWarningsHandlerBase &WarningsHandler)
Definition: Consumed.cpp:1152
const CXXBindTemporaryExpr * Tmp
Definition: Consumed.cpp:315
const VarTestResult & getVarTest() const
Definition: Consumed.cpp:362
T * getAnalysis()
Return the specified analysis object, lazily running the analysis if necessary.
A builtin binary operation expression such as "x + y" or "x <= y".
Definition: Expr.h:3287
bool isRValueReferenceType() const
Definition: Type.h:6319
const VarDecl * getVarDecl() const
Definition: CFG.h:389
bool isBackEdgeTarget(const CFGBlock *Block)
Definition: Consumed.cpp:1073
CastExpr - Base class for type casts, including both implicit casts (ImplicitCastExpr) and explicit c...
Definition: Expr.h:2998
Represents binding an expression to a temporary.
Definition: ExprCXX.h:1217
void VisitCXXMemberCallExpr(const CXXMemberCallExpr *Call)
Definition: Consumed.cpp:803
reverse_iterator rend()
Definition: CFG.h:709
static void splitVarStateForIfBinOp(const PropagationInfo &PInfo, ConsumedStateMap *ThenStates, ConsumedStateMap *ElseStates)
Definition: Consumed.cpp:951
static bool isConsumableType(const QualType &QT)
Definition: Consumed.cpp:144
void remove(const CXXBindTemporaryExpr *Tmp)
Remove the temporary value from our state map.
Definition: Consumed.cpp:1188
bool hasAttr() const
Definition: DeclBase.h:531
CXXRecordDecl * getAsCXXRecordDecl() const
Retrieves the CXXRecordDecl that this type refers to, either because the type is a RecordType or beca...
Definition: Type.cpp:1613
CXXConstructorDecl * getConstructor() const
Get the constructor that this expression will (ultimately) call.
Definition: ExprCXX.h:1334
const CXXBindTemporaryExpr * getBindTemporaryExpr() const
Definition: CFG.h:482
Represents a single basic block in a source-level CFG.
Definition: CFG.h:552
unsigned Offset
Definition: Format.cpp:1631
virtual void warnLoopStateMismatch(SourceLocation Loc, StringRef VariableName)
Warn that a variable&#39;s state doesn&#39;t match at the entry and exit of a loop.
Definition: Consumed.h:71
static bool isPointerOrRef(QualType ParamType)
Definition: Consumed.cpp:190
This represents one expression.
Definition: Expr.h:106
static StringRef stateToString(ConsumedState State)
Definition: Consumed.cpp:249
void discardInfo(const CFGBlock *Block)
Definition: Consumed.cpp:1053
Represents a source-level, intra-procedural CFG that represents the control-flow of a Stmt...
Definition: CFG.h:1003
std::unique_ptr< ConsumedStateMap > getInfo(const CFGBlock *Block)
Definition: Consumed.cpp:1058
void VisitMemberExpr(const MemberExpr *MExpr)
Definition: Consumed.cpp:854
const CXXRecordDecl * getPointeeCXXRecordDecl() const
If this is a pointer or reference to a RecordType, return the CXXRecordDecl that the type refers to...
Definition: Type.cpp:1598
const VarDecl * getVar() const
Definition: Consumed.cpp:377
Defines an enumeration for C++ overloaded operators.
bool allBackEdgesVisited(const CFGBlock *CurrBlock, const CFGBlock *TargetBlock)
Definition: Consumed.cpp:1004
void setState(const VarDecl *Var, ConsumedState State)
Set the consumed state of a given variable.
Definition: Consumed.cpp:1179
FunctionDecl * getDirectCallee()
If the callee is a FunctionDecl, return it. Otherwise return null.
Definition: Expr.h:2532
void VisitCastExpr(const CastExpr *Cast)
Definition: Consumed.cpp:757
PropagationInfo(ConsumedState State)
Definition: Consumed.cpp:351
ReturnStmt - This represents a return, optionally of an expression: return; return 4;...
Definition: Stmt.h:2443
UnaryOperator - This represents the unary-expression&#39;s (except sizeof and alignof), the postinc/postdec operators from postfix-expression, and various extensions.
Definition: Expr.h:1896
CXXMethodDecl * getMethodDecl() const
Retrieves the declaration of the called method.
Definition: ExprCXX.cpp:652
void VisitReturnStmt(const ReturnStmt *Ret)
Definition: Consumed.cpp:877
ValueDecl * getDecl()
Definition: Expr.h:1114
const Expr * getSubExpr() const
Definition: ExprCXX.h:1240
reverse_iterator rbegin()
Definition: CFG.h:708
SourceLocation getEndLoc() const LLVM_READONLY
Definition: Stmt.cpp:301
bool isConstQualified() const
Determine whether this type is const-qualified.
Definition: Type.h:6134
void addInfo(const CFGBlock *Block, ConsumedStateMap *StateMap, std::unique_ptr< ConsumedStateMap > &OwnedStateMap)
Definition: Consumed.cpp:1018
static ConsumedState mapConsumableAttrState(const QualType QT)
Definition: Consumed.cpp:194
static void setStateForVarOrTmp(ConsumedStateMap *StateMap, const PropagationInfo &PInfo, ConsumedState State)
Definition: Consumed.cpp:447
PropagationInfo invertTest() const
Definition: Consumed.cpp:425
CFGTerminator getTerminator()
Definition: CFG.h:840
void checkParamsForReturnTypestate(SourceLocation BlameLoc, ConsumedWarningsHandlerBase &WarningsHandler) const
Warn if any of the parameters being tracked are not in the state they were declared to be in upon ret...
Definition: Consumed.cpp:1090
Encodes a location in the source.
Expr * getRetValue()
Definition: Stmt.h:2476
Expr * getSubExpr() const
Definition: Expr.h:1926
void VisitDeclRefExpr(const DeclRefExpr *DeclRef)
Definition: Consumed.cpp:833
std::string getNameAsString() const
Get a human-readable name for the declaration, even if it is one of the special kinds of names (C++ c...
Definition: Decl.h:292
Represents a call to a member function that may be written either with member call syntax (e...
Definition: ExprCXX.h:171
DeclStmt - Adaptor class for mixing declarations with statements and expressions. ...
Definition: Stmt.h:1143
Represents a static or instance method of a struct/union/class.
Definition: DeclCXX.h:2041
static bool isTestingFunction(const FunctionDecl *FunDecl)
Definition: Consumed.cpp:186
static bool isKnownState(ConsumedState State)
Definition: Consumed.cpp:170
const ParmVarDecl * getParamDecl(unsigned i) const
Definition: Decl.h:2285
PropagationInfo(const BinaryOperator *Source, EffectiveOp EOp, const VarTestResult &LTest, const VarTestResult &RTest)
Definition: Consumed.cpp:330
const Decl * getDecl() const
void VisitUnaryOperator(const UnaryOperator *UOp)
Definition: Consumed.cpp:897
static bool isSetOnReadPtrType(const QualType &QT)
Definition: Consumed.cpp:164
unsigned getNumBlockIDs() const
Returns the total number of BlockIDs allocated (which start at 0).
Definition: CFG.h:1169
const VarTestResult & getLTest() const
Definition: Consumed.cpp:367
void intersect(const ConsumedStateMap &Other)
Merge this state map with another map.
Definition: Consumed.cpp:1133
void VisitVarDecl(const VarDecl *Var)
Definition: Consumed.cpp:917
SourceLocation getExprLoc() const LLVM_READONLY
getExprLoc - Return the preferred location for the arrow when diagnosing a problem with a generic exp...
Definition: Expr.cpp:215
Expr * getLHS() const
Definition: Expr.h:3327
void VisitCXXOperatorCallExpr(const CXXOperatorCallExpr *Call)
Definition: Consumed.cpp:813
pred_iterator pred_begin()
Definition: CFG.h:733
void checkCallability(const PropagationInfo &PInfo, const FunctionDecl *FunDecl, SourceLocation BlameLoc)
Definition: Consumed.cpp:580
void reset(ConsumedStateMap *NewStateMap)
Definition: Consumed.cpp:529
Dataflow Directional Tag Classes.
bool isValid() const
Return true if this is a valid SourceLocation object.
void clearTemporaries()
Clear the TmpMap.
Definition: Consumed.cpp:1110
OverloadedOperatorKind getOperator() const
Returns the kind of overloaded operator that this expression refers to.
Definition: ExprCXX.h:107
void VisitMaterializeTemporaryExpr(const MaterializeTemporaryExpr *Temp)
Definition: Consumed.cpp:849
bool isCopyConstructor(unsigned &TypeQuals) const
Whether this constructor is a copy constructor (C++ [class.copy]p2, which can be used to copy the cla...
Definition: DeclCXX.cpp:2365
const Expr * getInit() const
Definition: Decl.h:1220
unsigned pred_size() const
Definition: CFG.h:772
static std::string getAsString(SplitQualType split, const PrintingPolicy &Policy)
Definition: Type.h:971
bool isMoveConstructor(unsigned &TypeQuals) const
Determine whether this constructor is a move constructor (C++11 [class.copy]p3), which can be used to...
Definition: DeclCXX.cpp:2370
const Decl * getSingleDecl() const
Definition: Stmt.h:1158
A class that handles the analysis of uniqueness violations.
Definition: Consumed.h:241
ConsumedStateMap * borrowInfo(const CFGBlock *Block)
Definition: Consumed.cpp:1046
bool isSingleDecl() const
isSingleDecl - This method returns true if this DeclStmt refers to a single Decl. ...
Definition: Stmt.h:1156
Stmt * getStmt()
Definition: CFG.h:510
static bool isRValueRef(QualType ParamType)
Definition: Consumed.cpp:182
void markUnreachable()
Mark the block as unreachable.
Definition: Consumed.cpp:1173
static const TypeInfo & getInfo(unsigned id)
Definition: Types.cpp:34
PropagationInfo getInfo(const Expr *StmtNode) const
Definition: Consumed.cpp:520
T * getAttr() const
Definition: DeclBase.h:527
PropagationInfo(const VarDecl *Var, ConsumedState TestsFor)
Definition: Consumed.cpp:324
Opcode getOpcode() const
Definition: Expr.h:1921
Expr * getArg(unsigned Arg)
Return the specified argument.
Definition: ExprCXX.h:1413
void VisitCallExpr(const CallExpr *Call)
Definition: Consumed.cpp:741
decl_range decls()
Definition: Stmt.h:1186
ConsumedState getAsState(const ConsumedStateMap *StateMap) const
Definition: Consumed.cpp:387
Defines the C++ Decl subclasses, other than those for templates (found in DeclTemplate.h) and friends (in DeclFriend.h).
static SourceLocation getFirstStmtLoc(const CFGBlock *Block)
Definition: Consumed.cpp:62
MemberExpr - [C99 6.5.2.3] Structure and Union Members.
Definition: Expr.h:2682
Defines the clang::SourceLocation class and associated facilities.
void VisitCXXConstructExpr(const CXXConstructExpr *Call)
Definition: Consumed.cpp:772
Represents a C++ struct/union/class.
Definition: DeclCXX.h:300
bool handleCall(const CallExpr *Call, const Expr *ObjArg, const FunctionDecl *FunD)
Definition: Consumed.cpp:612
bool isVoidType() const
Definition: Type.h:6547
static bool isAutoCastType(const QualType &QT)
Definition: Consumed.cpp:154
void run(AnalysisDeclContext &AC)
Check a function&#39;s CFG for consumed violations.
Definition: Consumed.cpp:1305
Represents a top-level expression in a basic block.
Definition: CFG.h:56
CallExpr - Represents a function call (C99 6.5.2.2, C++ [expr.call]).
Definition: Expr.h:2396
RetTy Visit(PTR(Stmt) S, ParamTys... P)
Definition: StmtVisitor.h:43
static ConsumedState mapParamTypestateAttrState(const ParamTypestateAttr *PTAttr)
Definition: Consumed.cpp:212
static bool isCallableInState(const CallableWhenAttr *CWAttr, ConsumedState State)
Definition: Consumed.cpp:118
A reference to a declared variable, function, enum, etc.
Definition: Expr.h:1041
Expr * getRHS() const
Definition: Expr.h:3329
bool isPointerType() const
Definition: Type.h:6299
static SourceLocation getLastStmtLoc(const CFGBlock *Block)
Definition: Consumed.cpp:77
QualType getType() const
Definition: Decl.h:648
static ConsumedState mapSetTypestateAttrState(const SetTypestateAttr *STAttr)
Definition: Consumed.cpp:237
unsigned getNumParams() const
Return the number of parameters this function must have based on its FunctionType.
Definition: Decl.cpp:3055
bool hasInit() const
Definition: Decl.cpp:2164
Represents C++ object destructor implicitly generated at the end of full expression for temporary obj...
Definition: CFG.h:477
SourceLocation getReturnLoc() const
Definition: Stmt.h:2499
SourceLocation getLocation() const
Definition: DeclBase.h:418
static ConsumedState invertConsumedUnconsumed(ConsumedState State)
Definition: Consumed.cpp:104
Expr * IgnoreParens() LLVM_READONLY
IgnoreParens - Ignore parentheses.
Definition: Expr.cpp:2560
void VisitCXXBindTemporaryExpr(const CXXBindTemporaryExpr *Temp)
Definition: Consumed.cpp:761
CFGBlock & getExit()
Definition: CFG.h:1095