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diff --git a/clang/lib/Analysis/Consumed.cpp b/clang/lib/Analysis/Consumed.cpp
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+//===- Consumed.cpp -------------------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// A intra-procedural analysis for checking consumed properties. This is based,
+// in part, on research on linear types.
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/Analysis/Analyses/Consumed.h"
+#include "clang/AST/Attr.h"
+#include "clang/AST/Decl.h"
+#include "clang/AST/DeclCXX.h"
+#include "clang/AST/Expr.h"
+#include "clang/AST/ExprCXX.h"
+#include "clang/AST/Stmt.h"
+#include "clang/AST/StmtVisitor.h"
+#include "clang/AST/Type.h"
+#include "clang/Analysis/Analyses/PostOrderCFGView.h"
+#include "clang/Analysis/AnalysisDeclContext.h"
+#include "clang/Analysis/CFG.h"
+#include "clang/Basic/LLVM.h"
+#include "clang/Basic/OperatorKinds.h"
+#include "clang/Basic/SourceLocation.h"
+#include "llvm/ADT/DenseMap.h"
+#include "llvm/ADT/Optional.h"
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/ADT/StringRef.h"
+#include "llvm/Support/Casting.h"
+#include "llvm/Support/ErrorHandling.h"
+#include <cassert>
+#include <memory>
+#include <utility>
+
+// TODO: Adjust states of args to constructors in the same way that arguments to
+// function calls are handled.
+// TODO: Use information from tests in for- and while-loop conditional.
+// TODO: Add notes about the actual and expected state for
+// TODO: Correctly identify unreachable blocks when chaining boolean operators.
+// TODO: Adjust the parser and AttributesList class to support lists of
+// identifiers.
+// TODO: Warn about unreachable code.
+// TODO: Switch to using a bitmap to track unreachable blocks.
+// TODO: Handle variable definitions, e.g. bool valid = x.isValid();
+// if (valid) ...; (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() = default;
+
+static SourceLocation getFirstStmtLoc(const CFGBlock *Block) {
+ // Find the source location of the first statement in the block, if the block
+ // is not empty.
+ for (const auto &B : *Block)
+ if (Optional<CFGStmt> CS = B.getAs<CFGStmt>())
+ return CS->getStmt()->getBeginLoc();
+
+ // Block is empty.
+ // If we have one successor, return the first statement in that block
+ if (Block->succ_size() == 1 && *Block->succ_begin())
+ return getFirstStmtLoc(*Block->succ_begin());
+
+ return {};
+}
+
+static SourceLocation getLastStmtLoc(const CFGBlock *Block) {
+ // Find the source location of the last statement in the block, if the block
+ // is not empty.
+ if (const Stmt *StmtNode = Block->getTerminatorStmt()) {
+ return StmtNode->getBeginLoc();
+ } else {
+ for (CFGBlock::const_reverse_iterator BI = Block->rbegin(),
+ BE = Block->rend(); BI != BE; ++BI) {
+ if (Optional<CFGStmt> CS = BI->getAs<CFGStmt>())
+ return CS->getStmt()->getBeginLoc();
+ }
+ }
+
+ // If we have one successor, return the first statement in that block
+ SourceLocation Loc;
+ if (Block->succ_size() == 1 && *Block->succ_begin())
+ Loc = getFirstStmtLoc(*Block->succ_begin());
+ if (Loc.isValid())
+ return Loc;
+
+ // If we have one predecessor, return the last statement in that block
+ if (Block->pred_size() == 1 && *Block->pred_begin())
+ return getLastStmtLoc(*Block->pred_begin());
+
+ return Loc;
+}
+
+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 isCallableInState(const CallableWhenAttr *CWAttr,
+ ConsumedState State) {
+ for (const auto &S : CWAttr->callableStates()) {
+ ConsumedState MappedAttrState = CS_None;
+
+ switch (S) {
+ case CallableWhenAttr::Unknown:
+ MappedAttrState = CS_Unknown;
+ break;
+
+ case CallableWhenAttr::Unconsumed:
+ MappedAttrState = CS_Unconsumed;
+ break;
+
+ case CallableWhenAttr::Consumed:
+ MappedAttrState = CS_Consumed;
+ break;
+ }
+
+ if (MappedAttrState == State)
+ return true;
+ }
+
+ return false;
+}
+
+static bool isConsumableType(const QualType &QT) {
+ if (QT->isPointerType() || QT->isReferenceType())
+ return false;
+
+ if (const CXXRecordDecl *RD = QT->getAsCXXRecordDecl())
+ return RD->hasAttr<ConsumableAttr>();
+
+ return false;
+}
+
+static bool isAutoCastType(const QualType &QT) {
+ if (QT->isPointerType() || QT->isReferenceType())
+ return false;
+
+ if (const CXXRecordDecl *RD = QT->getAsCXXRecordDecl())
+ return RD->hasAttr<ConsumableAutoCastAttr>();
+
+ return false;
+}
+
+static bool isSetOnReadPtrType(const QualType &QT) {
+ if (const CXXRecordDecl *RD = QT->getPointeeCXXRecordDecl())
+ return RD->hasAttr<ConsumableSetOnReadAttr>();
+ return false;
+}
+
+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 isRValueRef(QualType ParamType) {
+ return ParamType->isRValueReferenceType();
+}
+
+static bool isTestingFunction(const FunctionDecl *FunDecl) {
+ return FunDecl->hasAttr<TestTypestateAttr>();
+}
+
+static bool isPointerOrRef(QualType ParamType) {
+ return ParamType->isPointerType() || ParamType->isReferenceType();
+}
+
+static ConsumedState mapConsumableAttrState(const QualType QT) {
+ assert(isConsumableType(QT));
+
+ const ConsumableAttr *CAttr =
+ QT->getAsCXXRecordDecl()->getAttr<ConsumableAttr>();
+
+ switch (CAttr->getDefaultState()) {
+ case ConsumableAttr::Unknown:
+ return CS_Unknown;
+ case ConsumableAttr::Unconsumed:
+ return CS_Unconsumed;
+ case ConsumableAttr::Consumed:
+ return CS_Consumed;
+ }
+ llvm_unreachable("invalid enum");
+}
+
+static ConsumedState
+mapParamTypestateAttrState(const ParamTypestateAttr *PTAttr) {
+ switch (PTAttr->getParamState()) {
+ case ParamTypestateAttr::Unknown:
+ return CS_Unknown;
+ case ParamTypestateAttr::Unconsumed:
+ return CS_Unconsumed;
+ case ParamTypestateAttr::Consumed:
+ return CS_Consumed;
+ }
+ llvm_unreachable("invalid_enum");
+}
+
+static ConsumedState
+mapReturnTypestateAttrState(const ReturnTypestateAttr *RTSAttr) {
+ switch (RTSAttr->getState()) {
+ case ReturnTypestateAttr::Unknown:
+ return CS_Unknown;
+ case ReturnTypestateAttr::Unconsumed:
+ return CS_Unconsumed;
+ case ReturnTypestateAttr::Consumed:
+ return CS_Consumed;
+ }
+ llvm_unreachable("invalid enum");
+}
+
+static ConsumedState mapSetTypestateAttrState(const SetTypestateAttr *STAttr) {
+ switch (STAttr->getNewState()) {
+ case SetTypestateAttr::Unknown:
+ return CS_Unknown;
+ case SetTypestateAttr::Unconsumed:
+ return CS_Unconsumed;
+ case SetTypestateAttr::Consumed:
+ return CS_Consumed;
+ }
+ llvm_unreachable("invalid_enum");
+}
+
+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");
+}
+
+static ConsumedState testsFor(const FunctionDecl *FunDecl) {
+ assert(isTestingFunction(FunDecl));
+ switch (FunDecl->getAttr<TestTypestateAttr>()->getTestState()) {
+ case TestTypestateAttr::Unconsumed:
+ return CS_Unconsumed;
+ case TestTypestateAttr::Consumed:
+ return CS_Consumed;
+ }
+ llvm_unreachable("invalid enum");
+}
+
+namespace {
+
+struct VarTestResult {
+ const VarDecl *Var;
+ ConsumedState TestsFor;
+};
+
+} // namespace
+
+namespace clang {
+namespace consumed {
+
+enum EffectiveOp {
+ EO_And,
+ EO_Or
+};
+
+class PropagationInfo {
+ enum {
+ IT_None,
+ IT_State,
+ IT_VarTest,
+ IT_BinTest,
+ IT_Var,
+ IT_Tmp
+ } InfoType = IT_None;
+
+ struct BinTestTy {
+ const BinaryOperator *Source;
+ EffectiveOp EOp;
+ VarTestResult LTest;
+ VarTestResult RTest;
+ };
+
+ union {
+ ConsumedState State;
+ VarTestResult VarTest;
+ const VarDecl *Var;
+ const CXXBindTemporaryExpr *Tmp;
+ BinTestTy BinTest;
+ };
+
+public:
+ PropagationInfo() = default;
+ PropagationInfo(const VarTestResult &VarTest)
+ : InfoType(IT_VarTest), VarTest(VarTest) {}
+
+ PropagationInfo(const VarDecl *Var, ConsumedState TestsFor)
+ : InfoType(IT_VarTest) {
+ VarTest.Var = Var;
+ VarTest.TestsFor = TestsFor;
+ }
+
+ PropagationInfo(const BinaryOperator *Source, EffectiveOp EOp,
+ const VarTestResult &LTest, 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) {}
+ PropagationInfo(const CXXBindTemporaryExpr *Tmp)
+ : InfoType(IT_Tmp), Tmp(Tmp) {}
+
+ const ConsumedState &getState() const {
+ assert(InfoType == IT_State);
+ return State;
+ }
+
+ const VarTestResult &getVarTest() const {
+ assert(InfoType == IT_VarTest);
+ return VarTest;
+ }
+
+ 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;
+ }
+
+ const CXXBindTemporaryExpr *getTmp() const {
+ assert(InfoType == IT_Tmp);
+ return Tmp;
+ }
+
+ ConsumedState getAsState(const ConsumedStateMap *StateMap) const {
+ assert(isVar() || isTmp() || isState());
+
+ if (isVar())
+ return StateMap->getState(Var);
+ else if (isTmp())
+ return StateMap->getState(Tmp);
+ else if (isState())
+ return State;
+ else
+ return CS_None;
+ }
+
+ 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 isVarTest() const { return InfoType == IT_VarTest; }
+ bool isBinTest() const { return InfoType == IT_BinTest; }
+ bool isVar() const { return InfoType == IT_Var; }
+ bool isTmp() const { return InfoType == IT_Tmp; }
+
+ bool isTest() const {
+ return InfoType == IT_VarTest || InfoType == IT_BinTest;
+ }
+
+ bool isPointerToValue() const {
+ return InfoType == IT_Var || InfoType == IT_Tmp;
+ }
+
+ PropagationInfo invertTest() const {
+ assert(InfoType == IT_VarTest || InfoType == IT_BinTest);
+
+ if (InfoType == IT_VarTest) {
+ return PropagationInfo(VarTest.Var,
+ invertConsumedUnconsumed(VarTest.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 {};
+ }
+ }
+};
+
+} // namespace consumed
+} // namespace clang
+
+static void
+setStateForVarOrTmp(ConsumedStateMap *StateMap, const PropagationInfo &PInfo,
+ ConsumedState State) {
+ assert(PInfo.isVar() || PInfo.isTmp());
+
+ if (PInfo.isVar())
+ StateMap->setState(PInfo.getVar(), State);
+ else
+ StateMap->setState(PInfo.getTmp(), State);
+}
+
+namespace clang {
+namespace consumed {
+
+class ConsumedStmtVisitor : public ConstStmtVisitor<ConsumedStmtVisitor> {
+ using MapType = llvm::DenseMap<const Stmt *, PropagationInfo>;
+ using PairType= std::pair<const Stmt *, PropagationInfo>;
+ using InfoEntry = MapType::iterator;
+ using ConstInfoEntry = MapType::const_iterator;
+
+ ConsumedAnalyzer &Analyzer;
+ ConsumedStateMap *StateMap;
+ MapType PropagationMap;
+
+ InfoEntry findInfo(const Expr *E) {
+ if (const auto Cleanups = dyn_cast<ExprWithCleanups>(E))
+ if (!Cleanups->cleanupsHaveSideEffects())
+ E = Cleanups->getSubExpr();
+ return PropagationMap.find(E->IgnoreParens());
+ }
+
+ ConstInfoEntry findInfo(const Expr *E) const {
+ if (const auto Cleanups = dyn_cast<ExprWithCleanups>(E))
+ if (!Cleanups->cleanupsHaveSideEffects())
+ E = Cleanups->getSubExpr();
+ return PropagationMap.find(E->IgnoreParens());
+ }
+
+ void insertInfo(const Expr *E, const PropagationInfo &PI) {
+ PropagationMap.insert(PairType(E->IgnoreParens(), PI));
+ }
+
+ void forwardInfo(const Expr *From, const Expr *To);
+ void copyInfo(const Expr *From, const Expr *To, ConsumedState CS);
+ ConsumedState getInfo(const Expr *From);
+ void setInfo(const Expr *To, ConsumedState NS);
+ void propagateReturnType(const Expr *Call, const FunctionDecl *Fun);
+
+public:
+ void checkCallability(const PropagationInfo &PInfo,
+ const FunctionDecl *FunDecl,
+ SourceLocation BlameLoc);
+ bool handleCall(const CallExpr *Call, const Expr *ObjArg,
+ const FunctionDecl *FunD);
+
+ void VisitBinaryOperator(const BinaryOperator *BinOp);
+ void VisitCallExpr(const CallExpr *Call);
+ void VisitCastExpr(const CastExpr *Cast);
+ void VisitCXXBindTemporaryExpr(const CXXBindTemporaryExpr *Temp);
+ 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 VisitReturnStmt(const ReturnStmt *Ret);
+ void VisitUnaryOperator(const UnaryOperator *UOp);
+ void VisitVarDecl(const VarDecl *Var);
+
+ ConsumedStmtVisitor(ConsumedAnalyzer &Analyzer, ConsumedStateMap *StateMap)
+ : Analyzer(Analyzer), StateMap(StateMap) {}
+
+ PropagationInfo getInfo(const Expr *StmtNode) const {
+ ConstInfoEntry Entry = findInfo(StmtNode);
+
+ if (Entry != PropagationMap.end())
+ return Entry->second;
+ else
+ return {};
+ }
+
+ void reset(ConsumedStateMap *NewStateMap) {
+ StateMap = NewStateMap;
+ }
+};
+
+} // namespace consumed
+} // namespace clang
+
+void ConsumedStmtVisitor::forwardInfo(const Expr *From, const Expr *To) {
+ InfoEntry Entry = findInfo(From);
+ if (Entry != PropagationMap.end())
+ insertInfo(To, Entry->second);
+}
+
+// Create a new state for To, which is initialized to the state of From.
+// If NS is not CS_None, sets the state of From to NS.
+void ConsumedStmtVisitor::copyInfo(const Expr *From, const Expr *To,
+ ConsumedState NS) {
+ InfoEntry Entry = findInfo(From);
+ if (Entry != PropagationMap.end()) {
+ PropagationInfo& PInfo = Entry->second;
+ ConsumedState CS = PInfo.getAsState(StateMap);
+ if (CS != CS_None)
+ insertInfo(To, PropagationInfo(CS));
+ if (NS != CS_None && PInfo.isPointerToValue())
+ setStateForVarOrTmp(StateMap, PInfo, NS);
+ }
+}
+
+// Get the ConsumedState for From
+ConsumedState ConsumedStmtVisitor::getInfo(const Expr *From) {
+ InfoEntry Entry = findInfo(From);
+ if (Entry != PropagationMap.end()) {
+ PropagationInfo& PInfo = Entry->second;
+ return PInfo.getAsState(StateMap);
+ }
+ return CS_None;
+}
+
+// If we already have info for To then update it, otherwise create a new entry.
+void ConsumedStmtVisitor::setInfo(const Expr *To, ConsumedState NS) {
+ InfoEntry Entry = findInfo(To);
+ if (Entry != PropagationMap.end()) {
+ PropagationInfo& PInfo = Entry->second;
+ if (PInfo.isPointerToValue())
+ setStateForVarOrTmp(StateMap, PInfo, NS);
+ } else if (NS != CS_None) {
+ insertInfo(To, PropagationInfo(NS));
+ }
+}
+
+void ConsumedStmtVisitor::checkCallability(const PropagationInfo &PInfo,
+ const FunctionDecl *FunDecl,
+ SourceLocation BlameLoc) {
+ assert(!PInfo.isTest());
+
+ const CallableWhenAttr *CWAttr = FunDecl->getAttr<CallableWhenAttr>();
+ if (!CWAttr)
+ return;
+
+ if (PInfo.isVar()) {
+ ConsumedState VarState = StateMap->getState(PInfo.getVar());
+
+ if (VarState == CS_None || isCallableInState(CWAttr, VarState))
+ return;
+
+ Analyzer.WarningsHandler.warnUseInInvalidState(
+ FunDecl->getNameAsString(), PInfo.getVar()->getNameAsString(),
+ stateToString(VarState), BlameLoc);
+ } else {
+ ConsumedState TmpState = PInfo.getAsState(StateMap);
+
+ if (TmpState == CS_None || isCallableInState(CWAttr, TmpState))
+ return;
+
+ Analyzer.WarningsHandler.warnUseOfTempInInvalidState(
+ FunDecl->getNameAsString(), stateToString(TmpState), BlameLoc);
+ }
+}
+
+// Factors out common behavior for function, method, and operator calls.
+// Check parameters and set parameter state if necessary.
+// Returns true if the state of ObjArg is set, or false otherwise.
+bool ConsumedStmtVisitor::handleCall(const CallExpr *Call, const Expr *ObjArg,
+ const FunctionDecl *FunD) {
+ unsigned Offset = 0;
+ if (isa<CXXOperatorCallExpr>(Call) && isa<CXXMethodDecl>(FunD))
+ Offset = 1; // first argument is 'this'
+
+ // check explicit parameters
+ for (unsigned Index = Offset; Index < Call->getNumArgs(); ++Index) {
+ // Skip variable argument lists.
+ if (Index - Offset >= FunD->getNumParams())
+ break;
+
+ const ParmVarDecl *Param = FunD->getParamDecl(Index - Offset);
+ QualType ParamType = Param->getType();
+
+ InfoEntry Entry = findInfo(Call->getArg(Index));
+
+ if (Entry == PropagationMap.end() || Entry->second.isTest())
+ continue;
+ PropagationInfo PInfo = Entry->second;
+
+ // Check that the parameter is in the correct state.
+ if (ParamTypestateAttr *PTA = Param->getAttr<ParamTypestateAttr>()) {
+ ConsumedState ParamState = PInfo.getAsState(StateMap);
+ ConsumedState ExpectedState = mapParamTypestateAttrState(PTA);
+
+ if (ParamState != ExpectedState)
+ Analyzer.WarningsHandler.warnParamTypestateMismatch(
+ Call->getArg(Index)->getExprLoc(),
+ stateToString(ExpectedState), stateToString(ParamState));
+ }
+
+ if (!(Entry->second.isVar() || Entry->second.isTmp()))
+ continue;
+
+ // Adjust state on the caller side.
+ if (ReturnTypestateAttr *RT = Param->getAttr<ReturnTypestateAttr>())
+ setStateForVarOrTmp(StateMap, PInfo, mapReturnTypestateAttrState(RT));
+ else if (isRValueRef(ParamType) || isConsumableType(ParamType))
+ setStateForVarOrTmp(StateMap, PInfo, consumed::CS_Consumed);
+ else if (isPointerOrRef(ParamType) &&
+ (!ParamType->getPointeeType().isConstQualified() ||
+ isSetOnReadPtrType(ParamType)))
+ setStateForVarOrTmp(StateMap, PInfo, consumed::CS_Unknown);
+ }
+
+ if (!ObjArg)
+ return false;
+
+ // check implicit 'self' parameter, if present
+ InfoEntry Entry = findInfo(ObjArg);
+ if (Entry != PropagationMap.end()) {
+ PropagationInfo PInfo = Entry->second;
+ checkCallability(PInfo, FunD, Call->getExprLoc());
+
+ if (SetTypestateAttr *STA = FunD->getAttr<SetTypestateAttr>()) {
+ if (PInfo.isVar()) {
+ StateMap->setState(PInfo.getVar(), mapSetTypestateAttrState(STA));
+ return true;
+ }
+ else if (PInfo.isTmp()) {
+ StateMap->setState(PInfo.getTmp(), mapSetTypestateAttrState(STA));
+ return true;
+ }
+ }
+ else if (isTestingFunction(FunD) && PInfo.isVar()) {
+ PropagationMap.insert(PairType(Call,
+ PropagationInfo(PInfo.getVar(), testsFor(FunD))));
+ }
+ }
+ return false;
+}
+
+void ConsumedStmtVisitor::propagateReturnType(const Expr *Call,
+ const FunctionDecl *Fun) {
+ QualType RetType = Fun->getCallResultType();
+ if (RetType->isReferenceType())
+ RetType = RetType->getPointeeType();
+
+ if (isConsumableType(RetType)) {
+ ConsumedState ReturnState;
+ if (ReturnTypestateAttr *RTA = Fun->getAttr<ReturnTypestateAttr>())
+ ReturnState = mapReturnTypestateAttrState(RTA);
+ else
+ ReturnState = mapConsumableAttrState(RetType);
+
+ PropagationMap.insert(PairType(Call, PropagationInfo(ReturnState)));
+ }
+}
+
+void ConsumedStmtVisitor::VisitBinaryOperator(const BinaryOperator *BinOp) {
+ switch (BinOp->getOpcode()) {
+ case BO_LAnd:
+ case BO_LOr : {
+ InfoEntry LEntry = findInfo(BinOp->getLHS()),
+ REntry = findInfo(BinOp->getRHS());
+
+ VarTestResult LTest, RTest;
+
+ if (LEntry != PropagationMap.end() && LEntry->second.isVarTest()) {
+ LTest = LEntry->second.getVarTest();
+ } else {
+ LTest.Var = nullptr;
+ LTest.TestsFor = CS_None;
+ }
+
+ if (REntry != PropagationMap.end() && REntry->second.isVarTest()) {
+ RTest = REntry->second.getVarTest();
+ } else {
+ RTest.Var = nullptr;
+ RTest.TestsFor = CS_None;
+ }
+
+ if (!(LTest.Var == nullptr && RTest.Var == nullptr))
+ 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) {
+ const FunctionDecl *FunDecl = Call->getDirectCallee();
+ if (!FunDecl)
+ return;
+
+ // Special case for the std::move function.
+ // TODO: Make this more specific. (Deferred)
+ if (Call->isCallToStdMove()) {
+ copyInfo(Call->getArg(0), Call, CS_Consumed);
+ return;
+ }
+
+ handleCall(Call, nullptr, FunDecl);
+ propagateReturnType(Call, FunDecl);
+}
+
+void ConsumedStmtVisitor::VisitCastExpr(const CastExpr *Cast) {
+ forwardInfo(Cast->getSubExpr(), Cast);
+}
+
+void ConsumedStmtVisitor::VisitCXXBindTemporaryExpr(
+ const CXXBindTemporaryExpr *Temp) {
+
+ InfoEntry Entry = findInfo(Temp->getSubExpr());
+
+ if (Entry != PropagationMap.end() && !Entry->second.isTest()) {
+ StateMap->setState(Temp, Entry->second.getAsState(StateMap));
+ PropagationMap.insert(PairType(Temp, PropagationInfo(Temp)));
+ }
+}
+
+void ConsumedStmtVisitor::VisitCXXConstructExpr(const CXXConstructExpr *Call) {
+ CXXConstructorDecl *Constructor = Call->getConstructor();
+
+ QualType ThisType = Constructor->getThisType()->getPointeeType();
+
+ if (!isConsumableType(ThisType))
+ return;
+
+ // FIXME: What should happen if someone annotates the move constructor?
+ if (ReturnTypestateAttr *RTA = Constructor->getAttr<ReturnTypestateAttr>()) {
+ // TODO: Adjust state of args appropriately.
+ ConsumedState RetState = mapReturnTypestateAttrState(RTA);
+ PropagationMap.insert(PairType(Call, PropagationInfo(RetState)));
+ } else if (Constructor->isDefaultConstructor()) {
+ PropagationMap.insert(PairType(Call,
+ PropagationInfo(consumed::CS_Consumed)));
+ } else if (Constructor->isMoveConstructor()) {
+ copyInfo(Call->getArg(0), Call, CS_Consumed);
+ } else if (Constructor->isCopyConstructor()) {
+ // Copy state from arg. If setStateOnRead then set arg to CS_Unknown.
+ ConsumedState NS =
+ isSetOnReadPtrType(Constructor->getThisType()) ?
+ CS_Unknown : CS_None;
+ copyInfo(Call->getArg(0), Call, NS);
+ } else {
+ // TODO: Adjust state of args appropriately.
+ ConsumedState RetState = mapConsumableAttrState(ThisType);
+ PropagationMap.insert(PairType(Call, PropagationInfo(RetState)));
+ }
+}
+
+void ConsumedStmtVisitor::VisitCXXMemberCallExpr(
+ const CXXMemberCallExpr *Call) {
+ CXXMethodDecl* MD = Call->getMethodDecl();
+ if (!MD)
+ return;
+
+ handleCall(Call, Call->getImplicitObjectArgument(), MD);
+ propagateReturnType(Call, MD);
+}
+
+void ConsumedStmtVisitor::VisitCXXOperatorCallExpr(
+ const CXXOperatorCallExpr *Call) {
+ const auto *FunDecl = dyn_cast_or_null<FunctionDecl>(Call->getDirectCallee());
+ if (!FunDecl) return;
+
+ if (Call->getOperator() == OO_Equal) {
+ ConsumedState CS = getInfo(Call->getArg(1));
+ if (!handleCall(Call, Call->getArg(0), FunDecl))
+ setInfo(Call->getArg(0), CS);
+ return;
+ }
+
+ if (const auto *MCall = dyn_cast<CXXMemberCallExpr>(Call))
+ handleCall(MCall, MCall->getImplicitObjectArgument(), FunDecl);
+ else
+ handleCall(Call, Call->getArg(0), FunDecl);
+
+ propagateReturnType(Call, FunDecl);
+}
+
+void ConsumedStmtVisitor::VisitDeclRefExpr(const DeclRefExpr *DeclRef) {
+ if (const auto *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 (const auto *DI : DeclS->decls())
+ if (isa<VarDecl>(DI))
+ VisitVarDecl(cast<VarDecl>(DI));
+
+ if (DeclS->isSingleDecl())
+ if (const auto *Var = dyn_cast_or_null<VarDecl>(DeclS->getSingleDecl()))
+ PropagationMap.insert(PairType(DeclS, PropagationInfo(Var)));
+}
+
+void ConsumedStmtVisitor::VisitMaterializeTemporaryExpr(
+ const MaterializeTemporaryExpr *Temp) {
+ forwardInfo(Temp->GetTemporaryExpr(), Temp);
+}
+
+void ConsumedStmtVisitor::VisitMemberExpr(const MemberExpr *MExpr) {
+ forwardInfo(MExpr->getBase(), MExpr);
+}
+
+void ConsumedStmtVisitor::VisitParmVarDecl(const ParmVarDecl *Param) {
+ QualType ParamType = Param->getType();
+ ConsumedState ParamState = consumed::CS_None;
+
+ if (const ParamTypestateAttr *PTA = Param->getAttr<ParamTypestateAttr>())
+ ParamState = mapParamTypestateAttrState(PTA);
+ else if (isConsumableType(ParamType))
+ ParamState = mapConsumableAttrState(ParamType);
+ else if (isRValueRef(ParamType) &&
+ isConsumableType(ParamType->getPointeeType()))
+ ParamState = mapConsumableAttrState(ParamType->getPointeeType());
+ else if (ParamType->isReferenceType() &&
+ isConsumableType(ParamType->getPointeeType()))
+ ParamState = consumed::CS_Unknown;
+
+ if (ParamState != CS_None)
+ StateMap->setState(Param, ParamState);
+}
+
+void ConsumedStmtVisitor::VisitReturnStmt(const ReturnStmt *Ret) {
+ ConsumedState ExpectedState = Analyzer.getExpectedReturnState();
+
+ if (ExpectedState != CS_None) {
+ InfoEntry Entry = findInfo(Ret->getRetValue());
+
+ if (Entry != PropagationMap.end()) {
+ ConsumedState RetState = Entry->second.getAsState(StateMap);
+
+ if (RetState != ExpectedState)
+ Analyzer.WarningsHandler.warnReturnTypestateMismatch(
+ Ret->getReturnLoc(), stateToString(ExpectedState),
+ stateToString(RetState));
+ }
+ }
+
+ StateMap->checkParamsForReturnTypestate(Ret->getBeginLoc(),
+ Analyzer.WarningsHandler);
+}
+
+void ConsumedStmtVisitor::VisitUnaryOperator(const UnaryOperator *UOp) {
+ InfoEntry Entry = findInfo(UOp->getSubExpr());
+ 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())
+ PropagationMap.insert(PairType(UOp, Entry->second.invertTest()));
+ break;
+
+ default:
+ break;
+ }
+}
+
+// TODO: See if I need to check for reference types here.
+void ConsumedStmtVisitor::VisitVarDecl(const VarDecl *Var) {
+ if (isConsumableType(Var->getType())) {
+ if (Var->hasInit()) {
+ MapType::iterator VIT = findInfo(Var->getInit()->IgnoreImplicit());
+ if (VIT != PropagationMap.end()) {
+ PropagationInfo PInfo = VIT->second;
+ ConsumedState St = PInfo.getAsState(StateMap);
+
+ if (St != consumed::CS_None) {
+ StateMap->setState(Var, St);
+ return;
+ }
+ }
+ }
+ // Otherwise
+ StateMap->setState(Var, consumed::CS_Unknown);
+ }
+}
+
+static 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);
+ ElseStates->setState(Test.Var, invertConsumedUnconsumed(Test.TestsFor));
+ } else if (VarState == invertConsumedUnconsumed(Test.TestsFor)) {
+ ThenStates->markUnreachable();
+ } else if (VarState == Test.TestsFor) {
+ ElseStates->markUnreachable();
+ }
+}
+
+static void splitVarStateForIfBinOp(const PropagationInfo &PInfo,
+ ConsumedStateMap *ThenStates,
+ ConsumedStateMap *ElseStates) {
+ const VarTestResult &LTest = 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)
+ ElseStates->markUnreachable();
+ else
+ ThenStates->markUnreachable();
+ }
+ } else {
+ if (LState == CS_Unknown) {
+ ElseStates->setState(LTest.Var,
+ invertConsumedUnconsumed(LTest.TestsFor));
+ } else if (LState == LTest.TestsFor) {
+ ElseStates->markUnreachable();
+ } else if (LState == invertConsumedUnconsumed(LTest.TestsFor) &&
+ isKnownState(RState)) {
+ if (RState == RTest.TestsFor)
+ 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 (RState == CS_Unknown)
+ ElseStates->setState(RTest.Var,
+ invertConsumedUnconsumed(RTest.TestsFor));
+ else if (RState == RTest.TestsFor)
+ ElseStates->markUnreachable();
+ }
+ }
+}
+
+bool ConsumedBlockInfo::allBackEdgesVisited(const CFGBlock *CurrBlock,
+ const CFGBlock *TargetBlock) {
+ assert(CurrBlock && "Block pointer must not be NULL");
+ assert(TargetBlock && "TargetBlock pointer must not be NULL");
+
+ unsigned int CurrBlockOrder = VisitOrder[CurrBlock->getBlockID()];
+ for (CFGBlock::const_pred_iterator PI = TargetBlock->pred_begin(),
+ PE = TargetBlock->pred_end(); PI != PE; ++PI) {
+ if (*PI && CurrBlockOrder < VisitOrder[(*PI)->getBlockID()] )
+ return false;
+ }
+ return true;
+}
+
+void ConsumedBlockInfo::addInfo(
+ const CFGBlock *Block, ConsumedStateMap *StateMap,
+ std::unique_ptr<ConsumedStateMap> &OwnedStateMap) {
+ assert(Block && "Block pointer must not be NULL");
+
+ auto &Entry = StateMapsArray[Block->getBlockID()];
+
+ if (Entry) {
+ Entry->intersect(*StateMap);
+ } else if (OwnedStateMap)
+ Entry = std::move(OwnedStateMap);
+ else
+ Entry = std::make_unique<ConsumedStateMap>(*StateMap);
+}
+
+void ConsumedBlockInfo::addInfo(const CFGBlock *Block,
+ std::unique_ptr<ConsumedStateMap> StateMap) {
+ assert(Block && "Block pointer must not be NULL");
+
+ auto &Entry = StateMapsArray[Block->getBlockID()];
+
+ if (Entry) {
+ Entry->intersect(*StateMap);
+ } else {
+ Entry = std::move(StateMap);
+ }
+}
+
+ConsumedStateMap* ConsumedBlockInfo::borrowInfo(const CFGBlock *Block) {
+ assert(Block && "Block pointer must not be NULL");
+ assert(StateMapsArray[Block->getBlockID()] && "Block has no block info");
+
+ return StateMapsArray[Block->getBlockID()].get();
+}
+
+void ConsumedBlockInfo::discardInfo(const CFGBlock *Block) {
+ StateMapsArray[Block->getBlockID()] = nullptr;
+}
+
+std::unique_ptr<ConsumedStateMap>
+ConsumedBlockInfo::getInfo(const CFGBlock *Block) {
+ assert(Block && "Block pointer must not be NULL");
+
+ auto &Entry = StateMapsArray[Block->getBlockID()];
+ return isBackEdgeTarget(Block) ? std::make_unique<ConsumedStateMap>(*Entry)
+ : std::move(Entry);
+}
+
+bool ConsumedBlockInfo::isBackEdge(const CFGBlock *From, const CFGBlock *To) {
+ assert(From && "From block must not be NULL");
+ assert(To && "From block must not be NULL");
+
+ return VisitOrder[From->getBlockID()] > VisitOrder[To->getBlockID()];
+}
+
+bool ConsumedBlockInfo::isBackEdgeTarget(const CFGBlock *Block) {
+ assert(Block && "Block pointer must not be NULL");
+
+ // Anything with less than two predecessors can't be the target of a back
+ // edge.
+ if (Block->pred_size() < 2)
+ return false;
+
+ unsigned int BlockVisitOrder = VisitOrder[Block->getBlockID()];
+ for (CFGBlock::const_pred_iterator PI = Block->pred_begin(),
+ PE = Block->pred_end(); PI != PE; ++PI) {
+ if (*PI && BlockVisitOrder < VisitOrder[(*PI)->getBlockID()])
+ return true;
+ }
+ return false;
+}
+
+void ConsumedStateMap::checkParamsForReturnTypestate(SourceLocation BlameLoc,
+ ConsumedWarningsHandlerBase &WarningsHandler) const {
+
+ for (const auto &DM : VarMap) {
+ if (isa<ParmVarDecl>(DM.first)) {
+ const auto *Param = cast<ParmVarDecl>(DM.first);
+ const ReturnTypestateAttr *RTA = Param->getAttr<ReturnTypestateAttr>();
+
+ if (!RTA)
+ continue;
+
+ ConsumedState ExpectedState = mapReturnTypestateAttrState(RTA);
+ if (DM.second != ExpectedState)
+ WarningsHandler.warnParamReturnTypestateMismatch(BlameLoc,
+ Param->getNameAsString(), stateToString(ExpectedState),
+ stateToString(DM.second));
+ }
+ }
+}
+
+void ConsumedStateMap::clearTemporaries() {
+ TmpMap.clear();
+}
+
+ConsumedState ConsumedStateMap::getState(const VarDecl *Var) const {
+ VarMapType::const_iterator Entry = VarMap.find(Var);
+
+ if (Entry != VarMap.end())
+ return Entry->second;
+
+ return CS_None;
+}
+
+ConsumedState
+ConsumedStateMap::getState(const CXXBindTemporaryExpr *Tmp) const {
+ TmpMapType::const_iterator Entry = TmpMap.find(Tmp);
+
+ if (Entry != TmpMap.end())
+ return Entry->second;
+
+ return CS_None;
+}
+
+void ConsumedStateMap::intersect(const ConsumedStateMap &Other) {
+ ConsumedState LocalState;
+
+ if (this->From && this->From == Other.From && !Other.Reachable) {
+ this->markUnreachable();
+ return;
+ }
+
+ for (const auto &DM : Other.VarMap) {
+ LocalState = this->getState(DM.first);
+
+ if (LocalState == CS_None)
+ continue;
+
+ if (LocalState != DM.second)
+ VarMap[DM.first] = CS_Unknown;
+ }
+}
+
+void ConsumedStateMap::intersectAtLoopHead(const CFGBlock *LoopHead,
+ const CFGBlock *LoopBack, const ConsumedStateMap *LoopBackStates,
+ ConsumedWarningsHandlerBase &WarningsHandler) {
+
+ ConsumedState LocalState;
+ SourceLocation BlameLoc = getLastStmtLoc(LoopBack);
+
+ for (const auto &DM : LoopBackStates->VarMap) {
+ LocalState = this->getState(DM.first);
+
+ if (LocalState == CS_None)
+ continue;
+
+ if (LocalState != DM.second) {
+ VarMap[DM.first] = CS_Unknown;
+ WarningsHandler.warnLoopStateMismatch(BlameLoc,
+ DM.first->getNameAsString());
+ }
+ }
+}
+
+void ConsumedStateMap::markUnreachable() {
+ this->Reachable = false;
+ VarMap.clear();
+ TmpMap.clear();
+}
+
+void ConsumedStateMap::setState(const VarDecl *Var, ConsumedState State) {
+ VarMap[Var] = State;
+}
+
+void ConsumedStateMap::setState(const CXXBindTemporaryExpr *Tmp,
+ ConsumedState State) {
+ TmpMap[Tmp] = State;
+}
+
+void ConsumedStateMap::remove(const CXXBindTemporaryExpr *Tmp) {
+ TmpMap.erase(Tmp);
+}
+
+bool ConsumedStateMap::operator!=(const ConsumedStateMap *Other) const {
+ for (const auto &DM : Other->VarMap)
+ if (this->getState(DM.first) != DM.second)
+ return true;
+ return false;
+}
+
+void ConsumedAnalyzer::determineExpectedReturnState(AnalysisDeclContext &AC,
+ const FunctionDecl *D) {
+ QualType ReturnType;
+ if (const auto *Constructor = dyn_cast<CXXConstructorDecl>(D)) {
+ ReturnType = Constructor->getThisType()->getPointeeType();
+ } else
+ ReturnType = D->getCallResultType();
+
+ if (const ReturnTypestateAttr *RTSAttr = D->getAttr<ReturnTypestateAttr>()) {
+ const CXXRecordDecl *RD = ReturnType->getAsCXXRecordDecl();
+ if (!RD || !RD->hasAttr<ConsumableAttr>()) {
+ // FIXME: This should be removed when template instantiation propagates
+ // attributes at template specialization definition, not
+ // declaration. When it is removed the test needs to be enabled
+ // in SemaDeclAttr.cpp.
+ WarningsHandler.warnReturnTypestateForUnconsumableType(
+ RTSAttr->getLocation(), ReturnType.getAsString());
+ ExpectedReturnState = CS_None;
+ } else
+ ExpectedReturnState = mapReturnTypestateAttrState(RTSAttr);
+ } else if (isConsumableType(ReturnType)) {
+ if (isAutoCastType(ReturnType)) // We can auto-cast the state to the
+ ExpectedReturnState = CS_None; // expected state.
+ else
+ ExpectedReturnState = mapConsumableAttrState(ReturnType);
+ }
+ else
+ ExpectedReturnState = CS_None;
+}
+
+bool ConsumedAnalyzer::splitState(const CFGBlock *CurrBlock,
+ const ConsumedStmtVisitor &Visitor) {
+ std::unique_ptr<ConsumedStateMap> FalseStates(
+ new ConsumedStateMap(*CurrStates));
+ PropagationInfo PInfo;
+
+ if (const auto *IfNode =
+ dyn_cast_or_null<IfStmt>(CurrBlock->getTerminator().getStmt())) {
+ const Expr *Cond = IfNode->getCond();
+
+ PInfo = Visitor.getInfo(Cond);
+ if (!PInfo.isValid() && isa<BinaryOperator>(Cond))
+ PInfo = Visitor.getInfo(cast<BinaryOperator>(Cond)->getRHS());
+
+ if (PInfo.isVarTest()) {
+ CurrStates->setSource(Cond);
+ FalseStates->setSource(Cond);
+ splitVarStateForIf(IfNode, PInfo.getVarTest(), CurrStates.get(),
+ FalseStates.get());
+ } else if (PInfo.isBinTest()) {
+ CurrStates->setSource(PInfo.testSourceNode());
+ FalseStates->setSource(PInfo.testSourceNode());
+ splitVarStateForIfBinOp(PInfo, CurrStates.get(), FalseStates.get());
+ } else {
+ return false;
+ }
+ } else if (const auto *BinOp =
+ dyn_cast_or_null<BinaryOperator>(CurrBlock->getTerminator().getStmt())) {
+ PInfo = Visitor.getInfo(BinOp->getLHS());
+ if (!PInfo.isVarTest()) {
+ if ((BinOp = dyn_cast_or_null<BinaryOperator>(BinOp->getLHS()))) {
+ PInfo = Visitor.getInfo(BinOp->getRHS());
+
+ if (!PInfo.isVarTest())
+ return false;
+ } else {
+ return false;
+ }
+ }
+
+ CurrStates->setSource(BinOp);
+ FalseStates->setSource(BinOp);
+
+ const VarTestResult &Test = PInfo.getVarTest();
+ 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 {
+ return false;
+ }
+
+ CFGBlock::const_succ_iterator SI = CurrBlock->succ_begin();
+
+ if (*SI)
+ BlockInfo.addInfo(*SI, std::move(CurrStates));
+ else
+ CurrStates = nullptr;
+
+ if (*++SI)
+ BlockInfo.addInfo(*SI, std::move(FalseStates));
+
+ return true;
+}
+
+void ConsumedAnalyzer::run(AnalysisDeclContext &AC) {
+ const auto *D = dyn_cast_or_null<FunctionDecl>(AC.getDecl());
+ if (!D)
+ return;
+
+ CFG *CFGraph = AC.getCFG();
+ if (!CFGraph)
+ return;
+
+ determineExpectedReturnState(AC, D);
+
+ PostOrderCFGView *SortedGraph = AC.getAnalysis<PostOrderCFGView>();
+ // AC.getCFG()->viewCFG(LangOptions());
+
+ BlockInfo = ConsumedBlockInfo(CFGraph->getNumBlockIDs(), SortedGraph);
+
+ CurrStates = std::make_unique<ConsumedStateMap>();
+ ConsumedStmtVisitor Visitor(*this, CurrStates.get());
+
+ // Add all trackable parameters to the state map.
+ for (const auto *PI : D->parameters())
+ Visitor.VisitParmVarDecl(PI);
+
+ // Visit all of the function's basic blocks.
+ for (const auto *CurrBlock : *SortedGraph) {
+ if (!CurrStates)
+ CurrStates = BlockInfo.getInfo(CurrBlock);
+
+ if (!CurrStates) {
+ continue;
+ } else if (!CurrStates->isReachable()) {
+ CurrStates = nullptr;
+ continue;
+ }
+
+ Visitor.reset(CurrStates.get());
+
+ // Visit all of the basic block's statements.
+ for (const auto &B : *CurrBlock) {
+ switch (B.getKind()) {
+ case CFGElement::Statement:
+ Visitor.Visit(B.castAs<CFGStmt>().getStmt());
+ break;
+
+ case CFGElement::TemporaryDtor: {
+ const CFGTemporaryDtor &DTor = B.castAs<CFGTemporaryDtor>();
+ const CXXBindTemporaryExpr *BTE = DTor.getBindTemporaryExpr();
+
+ Visitor.checkCallability(PropagationInfo(BTE),
+ DTor.getDestructorDecl(AC.getASTContext()),
+ BTE->getExprLoc());
+ CurrStates->remove(BTE);
+ break;
+ }
+
+ case CFGElement::AutomaticObjectDtor: {
+ const CFGAutomaticObjDtor &DTor = B.castAs<CFGAutomaticObjDtor>();
+ SourceLocation Loc = DTor.getTriggerStmt()->getEndLoc();
+ const VarDecl *Var = DTor.getVarDecl();
+
+ Visitor.checkCallability(PropagationInfo(Var),
+ DTor.getDestructorDecl(AC.getASTContext()),
+ Loc);
+ break;
+ }
+
+ default:
+ break;
+ }
+ }
+
+ // TODO: Handle other forms of branching with precision, including while-
+ // and for-loops. (Deferred)
+ if (!splitState(CurrBlock, Visitor)) {
+ CurrStates->setSource(nullptr);
+
+ if (CurrBlock->succ_size() > 1 ||
+ (CurrBlock->succ_size() == 1 &&
+ (*CurrBlock->succ_begin())->pred_size() > 1)) {
+
+ auto *RawState = CurrStates.get();
+
+ for (CFGBlock::const_succ_iterator SI = CurrBlock->succ_begin(),
+ SE = CurrBlock->succ_end(); SI != SE; ++SI) {
+ if (*SI == nullptr) continue;
+
+ if (BlockInfo.isBackEdge(CurrBlock, *SI)) {
+ BlockInfo.borrowInfo(*SI)->intersectAtLoopHead(
+ *SI, CurrBlock, RawState, WarningsHandler);
+
+ if (BlockInfo.allBackEdgesVisited(CurrBlock, *SI))
+ BlockInfo.discardInfo(*SI);
+ } else {
+ BlockInfo.addInfo(*SI, RawState, CurrStates);
+ }
+ }
+
+ CurrStates = nullptr;
+ }
+ }
+
+ if (CurrBlock == &AC.getCFG()->getExit() &&
+ D->getCallResultType()->isVoidType())
+ CurrStates->checkParamsForReturnTypestate(D->getLocation(),
+ WarningsHandler);
+ } // End of block iterator.
+
+ // Delete the last existing state map.
+ CurrStates = nullptr;
+
+ WarningsHandler.emitDiagnostics();
+}
generated by cgit v1.2.3 (git 2.25.1) at 2025-11-04 12:39:24 +0000