| //===- Consumed.cpp --------------------------------------------*- C++ --*-===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // A intra-procedural analysis for checking consumed properties. This is based, |
| // in part, on research on linear types. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "clang/AST/ASTContext.h" |
| #include "clang/AST/Attr.h" |
| #include "clang/AST/DeclCXX.h" |
| #include "clang/AST/ExprCXX.h" |
| #include "clang/AST/RecursiveASTVisitor.h" |
| #include "clang/AST/StmtVisitor.h" |
| #include "clang/AST/StmtCXX.h" |
| #include "clang/AST/Type.h" |
| #include "clang/Analysis/Analyses/PostOrderCFGView.h" |
| #include "clang/Analysis/AnalysisContext.h" |
| #include "clang/Analysis/CFG.h" |
| #include "clang/Analysis/Analyses/Consumed.h" |
| #include "clang/Basic/OperatorKinds.h" |
| #include "clang/Basic/SourceLocation.h" |
| #include "llvm/ADT/DenseMap.h" |
| #include "llvm/ADT/SmallVector.h" |
| #include "llvm/Support/Compiler.h" |
| #include "llvm/Support/raw_ostream.h" |
| |
| // TODO: Correctly identify unreachable blocks when chaining boolean operators. |
| // TODO: Warn about unreachable code. |
| // TODO: Switch to using a bitmap to track unreachable blocks. |
| // TODO: Mark variables as Unknown going into while- or for-loops only if they |
| // are referenced inside that block. (Deferred) |
| // TODO: Handle variable definitions, e.g. bool valid = x.isValid(); |
| // if (valid) ...; (Deferred) |
| // TODO: Add a method(s) to identify which method calls perform what state |
| // transitions. (Deferred) |
| // TODO: Take notes on state transitions to provide better warning messages. |
| // (Deferred) |
| // TODO: Test nested conditionals: A) Checking the same value multiple times, |
| // and 2) Checking different values. (Deferred) |
| |
| using namespace clang; |
| using namespace consumed; |
| |
| // Key method definition |
| ConsumedWarningsHandlerBase::~ConsumedWarningsHandlerBase() {} |
| |
| static ConsumedState invertConsumedUnconsumed(ConsumedState State) { |
| switch (State) { |
| case CS_Unconsumed: |
| return CS_Consumed; |
| case CS_Consumed: |
| return CS_Unconsumed; |
| case CS_None: |
| return CS_None; |
| case CS_Unknown: |
| return CS_Unknown; |
| } |
| llvm_unreachable("invalid enum"); |
| } |
| |
| static bool isKnownState(ConsumedState State) { |
| switch (State) { |
| case CS_Unconsumed: |
| case CS_Consumed: |
| return true; |
| case CS_None: |
| case CS_Unknown: |
| return false; |
| } |
| llvm_unreachable("invalid enum"); |
| } |
| |
| static bool isTestingFunction(const FunctionDecl *FunDecl) { |
| return FunDecl->hasAttr<TestsUnconsumedAttr>(); |
| } |
| |
| static StringRef stateToString(ConsumedState State) { |
| switch (State) { |
| case consumed::CS_None: |
| return "none"; |
| |
| case consumed::CS_Unknown: |
| return "unknown"; |
| |
| case consumed::CS_Unconsumed: |
| return "unconsumed"; |
| |
| case consumed::CS_Consumed: |
| return "consumed"; |
| } |
| llvm_unreachable("invalid enum"); |
| } |
| |
| namespace { |
| struct VarTestResult { |
| const VarDecl *Var; |
| ConsumedState TestsFor; |
| }; |
| } // end anonymous::VarTestResult |
| |
| namespace clang { |
| namespace consumed { |
| |
| enum EffectiveOp { |
| EO_And, |
| EO_Or |
| }; |
| |
| class PropagationInfo { |
| enum { |
| IT_None, |
| IT_State, |
| IT_Test, |
| IT_BinTest, |
| IT_Var |
| } InfoType; |
| |
| struct BinTestTy { |
| const BinaryOperator *Source; |
| EffectiveOp EOp; |
| VarTestResult LTest; |
| VarTestResult RTest; |
| }; |
| |
| union { |
| ConsumedState State; |
| VarTestResult Test; |
| const VarDecl *Var; |
| BinTestTy BinTest; |
| }; |
| |
| public: |
| PropagationInfo() : InfoType(IT_None) {} |
| |
| PropagationInfo(const VarTestResult &Test) : InfoType(IT_Test), Test(Test) {} |
| PropagationInfo(const VarDecl *Var, ConsumedState TestsFor) |
| : InfoType(IT_Test) { |
| |
| Test.Var = Var; |
| Test.TestsFor = TestsFor; |
| } |
| |
| PropagationInfo(const BinaryOperator *Source, EffectiveOp EOp, |
| const VarTestResult <est, const VarTestResult &RTest) |
| : InfoType(IT_BinTest) { |
| |
| BinTest.Source = Source; |
| BinTest.EOp = EOp; |
| BinTest.LTest = LTest; |
| BinTest.RTest = RTest; |
| } |
| |
| PropagationInfo(const BinaryOperator *Source, EffectiveOp EOp, |
| const VarDecl *LVar, ConsumedState LTestsFor, |
| const VarDecl *RVar, ConsumedState RTestsFor) |
| : InfoType(IT_BinTest) { |
| |
| BinTest.Source = Source; |
| BinTest.EOp = EOp; |
| BinTest.LTest.Var = LVar; |
| BinTest.LTest.TestsFor = LTestsFor; |
| BinTest.RTest.Var = RVar; |
| BinTest.RTest.TestsFor = RTestsFor; |
| } |
| |
| PropagationInfo(ConsumedState State) : InfoType(IT_State), State(State) {} |
| PropagationInfo(const VarDecl *Var) : InfoType(IT_Var), Var(Var) {} |
| |
| const ConsumedState & getState() const { |
| assert(InfoType == IT_State); |
| return State; |
| } |
| |
| const VarTestResult & getTest() const { |
| assert(InfoType == IT_Test); |
| return Test; |
| } |
| |
| const VarTestResult & getLTest() const { |
| assert(InfoType == IT_BinTest); |
| return BinTest.LTest; |
| } |
| |
| const VarTestResult & getRTest() const { |
| assert(InfoType == IT_BinTest); |
| return BinTest.RTest; |
| } |
| |
| const VarDecl * getVar() const { |
| assert(InfoType == IT_Var); |
| return Var; |
| } |
| |
| EffectiveOp testEffectiveOp() const { |
| assert(InfoType == IT_BinTest); |
| return BinTest.EOp; |
| } |
| |
| const BinaryOperator * testSourceNode() const { |
| assert(InfoType == IT_BinTest); |
| return BinTest.Source; |
| } |
| |
| bool isValid() const { return InfoType != IT_None; } |
| bool isState() const { return InfoType == IT_State; } |
| bool isTest() const { return InfoType == IT_Test; } |
| bool isBinTest() const { return InfoType == IT_BinTest; } |
| bool isVar() const { return InfoType == IT_Var; } |
| |
| PropagationInfo invertTest() const { |
| assert(InfoType == IT_Test || InfoType == IT_BinTest); |
| |
| if (InfoType == IT_Test) { |
| return PropagationInfo(Test.Var, invertConsumedUnconsumed(Test.TestsFor)); |
| |
| } else if (InfoType == IT_BinTest) { |
| return PropagationInfo(BinTest.Source, |
| BinTest.EOp == EO_And ? EO_Or : EO_And, |
| BinTest.LTest.Var, invertConsumedUnconsumed(BinTest.LTest.TestsFor), |
| BinTest.RTest.Var, invertConsumedUnconsumed(BinTest.RTest.TestsFor)); |
| } else { |
| return PropagationInfo(); |
| } |
| } |
| }; |
| |
| class ConsumedStmtVisitor : public ConstStmtVisitor<ConsumedStmtVisitor> { |
| |
| typedef llvm::DenseMap<const Stmt *, PropagationInfo> MapType; |
| typedef std::pair<const Stmt *, PropagationInfo> PairType; |
| typedef MapType::iterator InfoEntry; |
| typedef MapType::const_iterator ConstInfoEntry; |
| |
| AnalysisDeclContext &AC; |
| ConsumedAnalyzer &Analyzer; |
| ConsumedStateMap *StateMap; |
| MapType PropagationMap; |
| |
| void checkCallability(const PropagationInfo &PInfo, |
| const FunctionDecl *FunDecl, |
| const CallExpr *Call); |
| void forwardInfo(const Stmt *From, const Stmt *To); |
| void handleTestingFunctionCall(const CallExpr *Call, const VarDecl *Var); |
| bool isLikeMoveAssignment(const CXXMethodDecl *MethodDecl); |
| |
| public: |
| |
| void Visit(const Stmt *StmtNode); |
| |
| void VisitBinaryOperator(const BinaryOperator *BinOp); |
| void VisitCallExpr(const CallExpr *Call); |
| void VisitCastExpr(const CastExpr *Cast); |
| void VisitCXXConstructExpr(const CXXConstructExpr *Call); |
| void VisitCXXMemberCallExpr(const CXXMemberCallExpr *Call); |
| void VisitCXXOperatorCallExpr(const CXXOperatorCallExpr *Call); |
| void VisitDeclRefExpr(const DeclRefExpr *DeclRef); |
| void VisitDeclStmt(const DeclStmt *DelcS); |
| void VisitMaterializeTemporaryExpr(const MaterializeTemporaryExpr *Temp); |
| void VisitMemberExpr(const MemberExpr *MExpr); |
| void VisitParmVarDecl(const ParmVarDecl *Param); |
| void VisitUnaryOperator(const UnaryOperator *UOp); |
| void VisitVarDecl(const VarDecl *Var); |
| |
| ConsumedStmtVisitor(AnalysisDeclContext &AC, ConsumedAnalyzer &Analyzer, |
| ConsumedStateMap *StateMap) |
| : AC(AC), Analyzer(Analyzer), StateMap(StateMap) {} |
| |
| PropagationInfo getInfo(const Stmt *StmtNode) const { |
| ConstInfoEntry Entry = PropagationMap.find(StmtNode); |
| |
| if (Entry != PropagationMap.end()) |
| return Entry->second; |
| else |
| return PropagationInfo(); |
| } |
| |
| void reset(ConsumedStateMap *NewStateMap) { |
| StateMap = NewStateMap; |
| } |
| }; |
| |
| // TODO: When we support CallableWhenConsumed this will have to check for |
| // the different attributes and change the behavior bellow. (Deferred) |
| void ConsumedStmtVisitor::checkCallability(const PropagationInfo &PInfo, |
| const FunctionDecl *FunDecl, |
| const CallExpr *Call) { |
| |
| if (!FunDecl->hasAttr<CallableWhenUnconsumedAttr>()) return; |
| |
| if (PInfo.isVar()) { |
| const VarDecl *Var = PInfo.getVar(); |
| |
| switch (StateMap->getState(Var)) { |
| case CS_Consumed: |
| Analyzer.WarningsHandler.warnUseWhileConsumed( |
| FunDecl->getNameAsString(), Var->getNameAsString(), |
| Call->getExprLoc()); |
| break; |
| |
| case CS_Unknown: |
| Analyzer.WarningsHandler.warnUseInUnknownState( |
| FunDecl->getNameAsString(), Var->getNameAsString(), |
| Call->getExprLoc()); |
| break; |
| |
| case CS_None: |
| case CS_Unconsumed: |
| break; |
| } |
| |
| } else { |
| switch (PInfo.getState()) { |
| case CS_Consumed: |
| Analyzer.WarningsHandler.warnUseOfTempWhileConsumed( |
| FunDecl->getNameAsString(), Call->getExprLoc()); |
| break; |
| |
| case CS_Unknown: |
| Analyzer.WarningsHandler.warnUseOfTempInUnknownState( |
| FunDecl->getNameAsString(), Call->getExprLoc()); |
| break; |
| |
| case CS_None: |
| case CS_Unconsumed: |
| break; |
| } |
| } |
| } |
| |
| void ConsumedStmtVisitor::forwardInfo(const Stmt *From, const Stmt *To) { |
| InfoEntry Entry = PropagationMap.find(From); |
| |
| if (Entry != PropagationMap.end()) |
| PropagationMap.insert(PairType(To, Entry->second)); |
| } |
| |
| void ConsumedStmtVisitor::handleTestingFunctionCall(const CallExpr *Call, |
| const VarDecl *Var) { |
| |
| ConsumedState VarState = StateMap->getState(Var); |
| |
| if (VarState != CS_Unknown) { |
| SourceLocation CallLoc = Call->getExprLoc(); |
| |
| if (!CallLoc.isMacroID()) |
| Analyzer.WarningsHandler.warnUnnecessaryTest(Var->getNameAsString(), |
| stateToString(VarState), CallLoc); |
| } |
| |
| PropagationMap.insert(PairType(Call, PropagationInfo(Var, CS_Unconsumed))); |
| } |
| |
| bool ConsumedStmtVisitor::isLikeMoveAssignment( |
| const CXXMethodDecl *MethodDecl) { |
| |
| return MethodDecl->isMoveAssignmentOperator() || |
| (MethodDecl->getOverloadedOperator() == OO_Equal && |
| MethodDecl->getNumParams() == 1 && |
| MethodDecl->getParamDecl(0)->getType()->isRValueReferenceType()); |
| } |
| |
| void ConsumedStmtVisitor::Visit(const Stmt *StmtNode) { |
| |
| ConstStmtVisitor<ConsumedStmtVisitor>::Visit(StmtNode); |
| |
| for (Stmt::const_child_iterator CI = StmtNode->child_begin(), |
| CE = StmtNode->child_end(); CI != CE; ++CI) { |
| |
| PropagationMap.erase(*CI); |
| } |
| } |
| |
| void ConsumedStmtVisitor::VisitBinaryOperator(const BinaryOperator *BinOp) { |
| switch (BinOp->getOpcode()) { |
| case BO_LAnd: |
| case BO_LOr : { |
| InfoEntry LEntry = PropagationMap.find(BinOp->getLHS()), |
| REntry = PropagationMap.find(BinOp->getRHS()); |
| |
| VarTestResult LTest, RTest; |
| |
| if (LEntry != PropagationMap.end() && LEntry->second.isTest()) { |
| LTest = LEntry->second.getTest(); |
| |
| } else { |
| LTest.Var = NULL; |
| LTest.TestsFor = CS_None; |
| } |
| |
| if (REntry != PropagationMap.end() && REntry->second.isTest()) { |
| RTest = REntry->second.getTest(); |
| |
| } else { |
| RTest.Var = NULL; |
| RTest.TestsFor = CS_None; |
| } |
| |
| if (!(LTest.Var == NULL && RTest.Var == NULL)) |
| PropagationMap.insert(PairType(BinOp, PropagationInfo(BinOp, |
| static_cast<EffectiveOp>(BinOp->getOpcode() == BO_LOr), LTest, RTest))); |
| |
| break; |
| } |
| |
| case BO_PtrMemD: |
| case BO_PtrMemI: |
| forwardInfo(BinOp->getLHS(), BinOp); |
| break; |
| |
| default: |
| break; |
| } |
| } |
| |
| void ConsumedStmtVisitor::VisitCallExpr(const CallExpr *Call) { |
| if (const FunctionDecl *FunDecl = |
| dyn_cast_or_null<FunctionDecl>(Call->getDirectCallee())) { |
| |
| // Special case for the std::move function. |
| // TODO: Make this more specific. (Deferred) |
| if (FunDecl->getNameAsString() == "move") { |
| InfoEntry Entry = PropagationMap.find(Call->getArg(0)); |
| |
| if (Entry != PropagationMap.end()) { |
| PropagationMap.insert(PairType(Call, Entry->second)); |
| } |
| |
| return; |
| } |
| |
| unsigned Offset = Call->getNumArgs() - FunDecl->getNumParams(); |
| |
| for (unsigned Index = Offset; Index < Call->getNumArgs(); ++Index) { |
| QualType ParamType = FunDecl->getParamDecl(Index - Offset)->getType(); |
| |
| InfoEntry Entry = PropagationMap.find(Call->getArg(Index)); |
| |
| if (Entry == PropagationMap.end() || !Entry->second.isVar()) { |
| continue; |
| } |
| |
| PropagationInfo PInfo = Entry->second; |
| |
| if (ParamType->isRValueReferenceType() || |
| (ParamType->isLValueReferenceType() && |
| !cast<LValueReferenceType>(*ParamType).isSpelledAsLValue())) { |
| |
| StateMap->setState(PInfo.getVar(), consumed::CS_Consumed); |
| |
| } else if (!(ParamType.isConstQualified() || |
| ((ParamType->isReferenceType() || |
| ParamType->isPointerType()) && |
| ParamType->getPointeeType().isConstQualified()))) { |
| |
| StateMap->setState(PInfo.getVar(), consumed::CS_Unknown); |
| } |
| } |
| } |
| } |
| |
| void ConsumedStmtVisitor::VisitCastExpr(const CastExpr *Cast) { |
| forwardInfo(Cast->getSubExpr(), Cast); |
| } |
| |
| void ConsumedStmtVisitor::VisitCXXConstructExpr(const CXXConstructExpr *Call) { |
| CXXConstructorDecl *Constructor = Call->getConstructor(); |
| |
| ASTContext &CurrContext = AC.getASTContext(); |
| QualType ThisType = Constructor->getThisType(CurrContext)->getPointeeType(); |
| |
| if (Analyzer.isConsumableType(ThisType)) { |
| if (Constructor->hasAttr<ConsumesAttr>() || |
| Constructor->isDefaultConstructor()) { |
| |
| PropagationMap.insert(PairType(Call, |
| PropagationInfo(consumed::CS_Consumed))); |
| |
| } else if (Constructor->isMoveConstructor()) { |
| |
| PropagationInfo PInfo = |
| PropagationMap.find(Call->getArg(0))->second; |
| |
| if (PInfo.isVar()) { |
| const VarDecl* Var = PInfo.getVar(); |
| |
| PropagationMap.insert(PairType(Call, |
| PropagationInfo(StateMap->getState(Var)))); |
| |
| StateMap->setState(Var, consumed::CS_Consumed); |
| |
| } else { |
| PropagationMap.insert(PairType(Call, PInfo)); |
| } |
| |
| } else if (Constructor->isCopyConstructor()) { |
| MapType::iterator Entry = PropagationMap.find(Call->getArg(0)); |
| |
| if (Entry != PropagationMap.end()) |
| PropagationMap.insert(PairType(Call, Entry->second)); |
| |
| } else { |
| PropagationMap.insert(PairType(Call, |
| PropagationInfo(consumed::CS_Unconsumed))); |
| } |
| } |
| } |
| |
| void ConsumedStmtVisitor::VisitCXXMemberCallExpr( |
| const CXXMemberCallExpr *Call) { |
| |
| VisitCallExpr(Call); |
| |
| InfoEntry Entry = PropagationMap.find(Call->getCallee()->IgnoreParens()); |
| |
| if (Entry != PropagationMap.end()) { |
| PropagationInfo PInfo = Entry->second; |
| const CXXMethodDecl *MethodDecl = Call->getMethodDecl(); |
| |
| checkCallability(PInfo, MethodDecl, Call); |
| |
| if (PInfo.isVar()) { |
| if (isTestingFunction(MethodDecl)) |
| handleTestingFunctionCall(Call, PInfo.getVar()); |
| else if (MethodDecl->hasAttr<ConsumesAttr>()) |
| StateMap->setState(PInfo.getVar(), consumed::CS_Consumed); |
| } |
| } |
| } |
| |
| void ConsumedStmtVisitor::VisitCXXOperatorCallExpr( |
| const CXXOperatorCallExpr *Call) { |
| |
| const FunctionDecl *FunDecl = |
| dyn_cast_or_null<FunctionDecl>(Call->getDirectCallee()); |
| |
| if (!FunDecl) return; |
| |
| if (isa<CXXMethodDecl>(FunDecl) && |
| isLikeMoveAssignment(cast<CXXMethodDecl>(FunDecl))) { |
| |
| InfoEntry LEntry = PropagationMap.find(Call->getArg(0)); |
| InfoEntry REntry = PropagationMap.find(Call->getArg(1)); |
| |
| PropagationInfo LPInfo, RPInfo; |
| |
| if (LEntry != PropagationMap.end() && |
| REntry != PropagationMap.end()) { |
| |
| LPInfo = LEntry->second; |
| RPInfo = REntry->second; |
| |
| if (LPInfo.isVar() && RPInfo.isVar()) { |
| StateMap->setState(LPInfo.getVar(), |
| StateMap->getState(RPInfo.getVar())); |
| |
| StateMap->setState(RPInfo.getVar(), consumed::CS_Consumed); |
| |
| PropagationMap.insert(PairType(Call, LPInfo)); |
| |
| } else if (LPInfo.isVar() && !RPInfo.isVar()) { |
| StateMap->setState(LPInfo.getVar(), RPInfo.getState()); |
| |
| PropagationMap.insert(PairType(Call, LPInfo)); |
| |
| } else if (!LPInfo.isVar() && RPInfo.isVar()) { |
| PropagationMap.insert(PairType(Call, |
| PropagationInfo(StateMap->getState(RPInfo.getVar())))); |
| |
| StateMap->setState(RPInfo.getVar(), consumed::CS_Consumed); |
| |
| } else { |
| PropagationMap.insert(PairType(Call, RPInfo)); |
| } |
| |
| } else if (LEntry != PropagationMap.end() && |
| REntry == PropagationMap.end()) { |
| |
| LPInfo = LEntry->second; |
| |
| if (LPInfo.isVar()) { |
| StateMap->setState(LPInfo.getVar(), consumed::CS_Unknown); |
| |
| PropagationMap.insert(PairType(Call, LPInfo)); |
| |
| } else { |
| PropagationMap.insert(PairType(Call, |
| PropagationInfo(consumed::CS_Unknown))); |
| } |
| |
| } else if (LEntry == PropagationMap.end() && |
| REntry != PropagationMap.end()) { |
| |
| RPInfo = REntry->second; |
| |
| if (RPInfo.isVar()) { |
| const VarDecl *Var = RPInfo.getVar(); |
| |
| PropagationMap.insert(PairType(Call, |
| PropagationInfo(StateMap->getState(Var)))); |
| |
| StateMap->setState(Var, consumed::CS_Consumed); |
| |
| } else { |
| PropagationMap.insert(PairType(Call, RPInfo)); |
| } |
| } |
| |
| } else { |
| |
| VisitCallExpr(Call); |
| |
| InfoEntry Entry = PropagationMap.find(Call->getArg(0)); |
| |
| if (Entry != PropagationMap.end()) { |
| PropagationInfo PInfo = Entry->second; |
| |
| checkCallability(PInfo, FunDecl, Call); |
| |
| if (PInfo.isVar()) { |
| if (isTestingFunction(FunDecl)) |
| handleTestingFunctionCall(Call, PInfo.getVar()); |
| else if (FunDecl->hasAttr<ConsumesAttr>()) |
| StateMap->setState(PInfo.getVar(), consumed::CS_Consumed); |
| } |
| } |
| } |
| } |
| |
| void ConsumedStmtVisitor::VisitDeclRefExpr(const DeclRefExpr *DeclRef) { |
| if (const VarDecl *Var = dyn_cast_or_null<VarDecl>(DeclRef->getDecl())) |
| if (StateMap->getState(Var) != consumed::CS_None) |
| PropagationMap.insert(PairType(DeclRef, PropagationInfo(Var))); |
| } |
| |
| void ConsumedStmtVisitor::VisitDeclStmt(const DeclStmt *DeclS) { |
| for (DeclStmt::const_decl_iterator DI = DeclS->decl_begin(), |
| DE = DeclS->decl_end(); DI != DE; ++DI) { |
| |
| if (isa<VarDecl>(*DI)) VisitVarDecl(cast<VarDecl>(*DI)); |
| } |
| |
| if (DeclS->isSingleDecl()) |
| if (const VarDecl *Var = dyn_cast_or_null<VarDecl>(DeclS->getSingleDecl())) |
| PropagationMap.insert(PairType(DeclS, PropagationInfo(Var))); |
| } |
| |
| void ConsumedStmtVisitor::VisitMaterializeTemporaryExpr( |
| const MaterializeTemporaryExpr *Temp) { |
| |
| InfoEntry Entry = PropagationMap.find(Temp->GetTemporaryExpr()); |
| |
| if (Entry != PropagationMap.end()) |
| PropagationMap.insert(PairType(Temp, Entry->second)); |
| } |
| |
| void ConsumedStmtVisitor::VisitMemberExpr(const MemberExpr *MExpr) { |
| forwardInfo(MExpr->getBase(), MExpr); |
| } |
| |
| |
| void ConsumedStmtVisitor::VisitParmVarDecl(const ParmVarDecl *Param) { |
| if (Analyzer.isConsumableType(Param->getType())) |
| StateMap->setState(Param, consumed::CS_Unknown); |
| } |
| |
| void ConsumedStmtVisitor::VisitUnaryOperator(const UnaryOperator *UOp) { |
| InfoEntry Entry = PropagationMap.find(UOp->getSubExpr()->IgnoreParens()); |
| if (Entry == PropagationMap.end()) return; |
| |
| switch (UOp->getOpcode()) { |
| case UO_AddrOf: |
| PropagationMap.insert(PairType(UOp, Entry->second)); |
| break; |
| |
| case UO_LNot: |
| if (Entry->second.isTest() || Entry->second.isBinTest()) |
| PropagationMap.insert(PairType(UOp, Entry->second.invertTest())); |
| break; |
| |
| default: |
| break; |
| } |
| } |
| |
| void ConsumedStmtVisitor::VisitVarDecl(const VarDecl *Var) { |
| if (Analyzer.isConsumableType(Var->getType())) { |
| if (Var->hasInit()) { |
| PropagationInfo PInfo = |
| PropagationMap.find(Var->getInit())->second; |
| |
| StateMap->setState(Var, PInfo.isVar() ? |
| StateMap->getState(PInfo.getVar()) : PInfo.getState()); |
| |
| } else { |
| StateMap->setState(Var, consumed::CS_Unknown); |
| } |
| } |
| } |
| }} // end clang::consumed::ConsumedStmtVisitor |
| |
| namespace clang { |
| namespace consumed { |
| |
| void splitVarStateForIf(const IfStmt * IfNode, const VarTestResult &Test, |
| ConsumedStateMap *ThenStates, |
| ConsumedStateMap *ElseStates) { |
| |
| ConsumedState VarState = ThenStates->getState(Test.Var); |
| |
| if (VarState == CS_Unknown) { |
| ThenStates->setState(Test.Var, Test.TestsFor); |
| if (ElseStates) |
| ElseStates->setState(Test.Var, invertConsumedUnconsumed(Test.TestsFor)); |
| |
| } else if (VarState == invertConsumedUnconsumed(Test.TestsFor)) { |
| ThenStates->markUnreachable(); |
| |
| } else if (VarState == Test.TestsFor && ElseStates) { |
| ElseStates->markUnreachable(); |
| } |
| } |
| |
| void splitVarStateForIfBinOp(const PropagationInfo &PInfo, |
| ConsumedStateMap *ThenStates, ConsumedStateMap *ElseStates) { |
| |
| const VarTestResult <est = PInfo.getLTest(), |
| &RTest = PInfo.getRTest(); |
| |
| ConsumedState LState = LTest.Var ? ThenStates->getState(LTest.Var) : CS_None, |
| RState = RTest.Var ? ThenStates->getState(RTest.Var) : CS_None; |
| |
| if (LTest.Var) { |
| if (PInfo.testEffectiveOp() == EO_And) { |
| if (LState == CS_Unknown) { |
| ThenStates->setState(LTest.Var, LTest.TestsFor); |
| |
| } else if (LState == invertConsumedUnconsumed(LTest.TestsFor)) { |
| ThenStates->markUnreachable(); |
| |
| } else if (LState == LTest.TestsFor && isKnownState(RState)) { |
| if (RState == RTest.TestsFor) { |
| if (ElseStates) |
| ElseStates->markUnreachable(); |
| } else { |
| ThenStates->markUnreachable(); |
| } |
| } |
| |
| } else { |
| if (LState == CS_Unknown && ElseStates) { |
| ElseStates->setState(LTest.Var, |
| invertConsumedUnconsumed(LTest.TestsFor)); |
| |
| } else if (LState == LTest.TestsFor && ElseStates) { |
| ElseStates->markUnreachable(); |
| |
| } else if (LState == invertConsumedUnconsumed(LTest.TestsFor) && |
| isKnownState(RState)) { |
| |
| if (RState == RTest.TestsFor) { |
| if (ElseStates) |
| ElseStates->markUnreachable(); |
| } else { |
| ThenStates->markUnreachable(); |
| } |
| } |
| } |
| } |
| |
| if (RTest.Var) { |
| if (PInfo.testEffectiveOp() == EO_And) { |
| if (RState == CS_Unknown) |
| ThenStates->setState(RTest.Var, RTest.TestsFor); |
| else if (RState == invertConsumedUnconsumed(RTest.TestsFor)) |
| ThenStates->markUnreachable(); |
| |
| } else if (ElseStates) { |
| if (RState == CS_Unknown) |
| ElseStates->setState(RTest.Var, |
| invertConsumedUnconsumed(RTest.TestsFor)); |
| else if (RState == RTest.TestsFor) |
| ElseStates->markUnreachable(); |
| } |
| } |
| } |
| |
| void ConsumedBlockInfo::addInfo(const CFGBlock *Block, |
| ConsumedStateMap *StateMap, |
| bool &AlreadyOwned) { |
| |
| if (VisitedBlocks.alreadySet(Block)) return; |
| |
| ConsumedStateMap *Entry = StateMapsArray[Block->getBlockID()]; |
| |
| if (Entry) { |
| Entry->intersect(StateMap); |
| |
| } else if (AlreadyOwned) { |
| StateMapsArray[Block->getBlockID()] = new ConsumedStateMap(*StateMap); |
| |
| } else { |
| StateMapsArray[Block->getBlockID()] = StateMap; |
| AlreadyOwned = true; |
| } |
| } |
| |
| void ConsumedBlockInfo::addInfo(const CFGBlock *Block, |
| ConsumedStateMap *StateMap) { |
| |
| if (VisitedBlocks.alreadySet(Block)) { |
| delete StateMap; |
| return; |
| } |
| |
| ConsumedStateMap *Entry = StateMapsArray[Block->getBlockID()]; |
| |
| if (Entry) { |
| Entry->intersect(StateMap); |
| delete StateMap; |
| |
| } else { |
| StateMapsArray[Block->getBlockID()] = StateMap; |
| } |
| } |
| |
| ConsumedStateMap* ConsumedBlockInfo::getInfo(const CFGBlock *Block) { |
| return StateMapsArray[Block->getBlockID()]; |
| } |
| |
| void ConsumedBlockInfo::markVisited(const CFGBlock *Block) { |
| VisitedBlocks.insert(Block); |
| } |
| |
| ConsumedState ConsumedStateMap::getState(const VarDecl *Var) { |
| MapType::const_iterator Entry = Map.find(Var); |
| |
| if (Entry != Map.end()) { |
| return Entry->second; |
| |
| } else { |
| return CS_None; |
| } |
| } |
| |
| void ConsumedStateMap::intersect(const ConsumedStateMap *Other) { |
| ConsumedState LocalState; |
| |
| if (this->From && this->From == Other->From && !Other->Reachable) { |
| this->markUnreachable(); |
| return; |
| } |
| |
| for (MapType::const_iterator DMI = Other->Map.begin(), |
| DME = Other->Map.end(); DMI != DME; ++DMI) { |
| |
| LocalState = this->getState(DMI->first); |
| |
| if (LocalState == CS_None) |
| continue; |
| |
| if (LocalState != DMI->second) |
| Map[DMI->first] = CS_Unknown; |
| } |
| } |
| |
| void ConsumedStateMap::markUnreachable() { |
| this->Reachable = false; |
| Map.clear(); |
| } |
| |
| void ConsumedStateMap::makeUnknown() { |
| for (MapType::const_iterator DMI = Map.begin(), DME = Map.end(); DMI != DME; |
| ++DMI) { |
| |
| Map[DMI->first] = CS_Unknown; |
| } |
| } |
| |
| void ConsumedStateMap::setState(const VarDecl *Var, ConsumedState State) { |
| Map[Var] = State; |
| } |
| |
| void ConsumedStateMap::remove(const VarDecl *Var) { |
| Map.erase(Var); |
| } |
| |
| bool ConsumedAnalyzer::isConsumableType(QualType Type) { |
| const CXXRecordDecl *RD = |
| dyn_cast_or_null<CXXRecordDecl>(Type->getAsCXXRecordDecl()); |
| |
| if (!RD) return false; |
| |
| std::pair<CacheMapType::iterator, bool> Entry = |
| ConsumableTypeCache.insert(std::make_pair(RD, false)); |
| |
| if (Entry.second) |
| Entry.first->second = hasConsumableAttributes(RD); |
| |
| return Entry.first->second; |
| } |
| |
| // TODO: Walk the base classes to see if any of them are unique types. |
| // (Deferred) |
| bool ConsumedAnalyzer::hasConsumableAttributes(const CXXRecordDecl *RD) { |
| for (CXXRecordDecl::method_iterator MI = RD->method_begin(), |
| ME = RD->method_end(); MI != ME; ++MI) { |
| |
| for (Decl::attr_iterator AI = (*MI)->attr_begin(), AE = (*MI)->attr_end(); |
| AI != AE; ++AI) { |
| |
| switch ((*AI)->getKind()) { |
| case attr::CallableWhenUnconsumed: |
| case attr::TestsUnconsumed: |
| return true; |
| |
| default: |
| break; |
| } |
| } |
| } |
| |
| return false; |
| } |
| |
| bool ConsumedAnalyzer::splitState(const CFGBlock *CurrBlock, |
| const ConsumedStmtVisitor &Visitor) { |
| |
| ConsumedStateMap *FalseStates = new ConsumedStateMap(*CurrStates); |
| PropagationInfo PInfo; |
| |
| if (const IfStmt *IfNode = |
| dyn_cast_or_null<IfStmt>(CurrBlock->getTerminator().getStmt())) { |
| |
| bool HasElse = IfNode->getElse() != NULL; |
| const Stmt *Cond = IfNode->getCond(); |
| |
| PInfo = Visitor.getInfo(Cond); |
| if (!PInfo.isValid() && isa<BinaryOperator>(Cond)) |
| PInfo = Visitor.getInfo(cast<BinaryOperator>(Cond)->getRHS()); |
| |
| if (PInfo.isTest()) { |
| CurrStates->setSource(Cond); |
| FalseStates->setSource(Cond); |
| |
| splitVarStateForIf(IfNode, PInfo.getTest(), CurrStates, |
| HasElse ? FalseStates : NULL); |
| |
| } else if (PInfo.isBinTest()) { |
| CurrStates->setSource(PInfo.testSourceNode()); |
| FalseStates->setSource(PInfo.testSourceNode()); |
| |
| splitVarStateForIfBinOp(PInfo, CurrStates, HasElse ? FalseStates : NULL); |
| |
| } else { |
| delete FalseStates; |
| return false; |
| } |
| |
| } else if (const BinaryOperator *BinOp = |
| dyn_cast_or_null<BinaryOperator>(CurrBlock->getTerminator().getStmt())) { |
| |
| PInfo = Visitor.getInfo(BinOp->getLHS()); |
| if (!PInfo.isTest()) { |
| if ((BinOp = dyn_cast_or_null<BinaryOperator>(BinOp->getLHS()))) { |
| PInfo = Visitor.getInfo(BinOp->getRHS()); |
| |
| if (!PInfo.isTest()) { |
| delete FalseStates; |
| return false; |
| } |
| |
| } else { |
| delete FalseStates; |
| return false; |
| } |
| } |
| |
| CurrStates->setSource(BinOp); |
| FalseStates->setSource(BinOp); |
| |
| const VarTestResult &Test = PInfo.getTest(); |
| ConsumedState VarState = CurrStates->getState(Test.Var); |
| |
| if (BinOp->getOpcode() == BO_LAnd) { |
| if (VarState == CS_Unknown) |
| CurrStates->setState(Test.Var, Test.TestsFor); |
| else if (VarState == invertConsumedUnconsumed(Test.TestsFor)) |
| CurrStates->markUnreachable(); |
| |
| } else if (BinOp->getOpcode() == BO_LOr) { |
| if (VarState == CS_Unknown) |
| FalseStates->setState(Test.Var, |
| invertConsumedUnconsumed(Test.TestsFor)); |
| else if (VarState == Test.TestsFor) |
| FalseStates->markUnreachable(); |
| } |
| |
| } else { |
| delete FalseStates; |
| return false; |
| } |
| |
| CFGBlock::const_succ_iterator SI = CurrBlock->succ_begin(); |
| |
| if (*SI) |
| BlockInfo.addInfo(*SI, CurrStates); |
| else |
| delete CurrStates; |
| |
| if (*++SI) |
| BlockInfo.addInfo(*SI, FalseStates); |
| else |
| delete FalseStates; |
| |
| CurrStates = NULL; |
| return true; |
| } |
| |
| void ConsumedAnalyzer::run(AnalysisDeclContext &AC) { |
| const FunctionDecl *D = dyn_cast_or_null<FunctionDecl>(AC.getDecl()); |
| |
| if (!D) return; |
| |
| BlockInfo = ConsumedBlockInfo(AC.getCFG()); |
| |
| PostOrderCFGView *SortedGraph = AC.getAnalysis<PostOrderCFGView>(); |
| |
| CurrStates = new ConsumedStateMap(); |
| ConsumedStmtVisitor Visitor(AC, *this, CurrStates); |
| |
| // Add all trackable parameters to the state map. |
| for (FunctionDecl::param_const_iterator PI = D->param_begin(), |
| PE = D->param_end(); PI != PE; ++PI) { |
| Visitor.VisitParmVarDecl(*PI); |
| } |
| |
| // Visit all of the function's basic blocks. |
| for (PostOrderCFGView::iterator I = SortedGraph->begin(), |
| E = SortedGraph->end(); I != E; ++I) { |
| |
| const CFGBlock *CurrBlock = *I; |
| BlockInfo.markVisited(CurrBlock); |
| |
| if (CurrStates == NULL) |
| CurrStates = BlockInfo.getInfo(CurrBlock); |
| |
| if (!CurrStates) { |
| continue; |
| |
| } else if (!CurrStates->isReachable()) { |
| delete CurrStates; |
| CurrStates = NULL; |
| continue; |
| } |
| |
| Visitor.reset(CurrStates); |
| |
| // Visit all of the basic block's statements. |
| for (CFGBlock::const_iterator BI = CurrBlock->begin(), |
| BE = CurrBlock->end(); BI != BE; ++BI) { |
| |
| switch (BI->getKind()) { |
| case CFGElement::Statement: |
| Visitor.Visit(BI->castAs<CFGStmt>().getStmt()); |
| break; |
| case CFGElement::AutomaticObjectDtor: |
| CurrStates->remove(BI->castAs<CFGAutomaticObjDtor>().getVarDecl()); |
| default: |
| break; |
| } |
| } |
| |
| // TODO: Handle other forms of branching with precision, including while- |
| // and for-loops. (Deferred) |
| if (!splitState(CurrBlock, Visitor)) { |
| CurrStates->setSource(NULL); |
| |
| if (CurrBlock->succ_size() > 1) { |
| CurrStates->makeUnknown(); |
| |
| bool OwnershipTaken = false; |
| |
| for (CFGBlock::const_succ_iterator SI = CurrBlock->succ_begin(), |
| SE = CurrBlock->succ_end(); SI != SE; ++SI) { |
| |
| if (*SI) BlockInfo.addInfo(*SI, CurrStates, OwnershipTaken); |
| } |
| |
| if (!OwnershipTaken) |
| delete CurrStates; |
| |
| CurrStates = NULL; |
| |
| } else if (CurrBlock->succ_size() == 1 && |
| (*CurrBlock->succ_begin())->pred_size() > 1) { |
| |
| BlockInfo.addInfo(*CurrBlock->succ_begin(), CurrStates); |
| CurrStates = NULL; |
| } |
| } |
| } // End of block iterator. |
| |
| // Delete the last existing state map. |
| delete CurrStates; |
| |
| WarningsHandler.emitDiagnostics(); |
| } |
| }} // end namespace clang::consumed |