| //===--- SemaStmt.cpp - Semantic Analysis for Statements ------------------===// | 
 | // | 
 | //                     The LLVM Compiler Infrastructure | 
 | // | 
 | // This file is distributed under the University of Illinois Open Source | 
 | // License. See LICENSE.TXT for details. | 
 | // | 
 | //===----------------------------------------------------------------------===// | 
 | // | 
 | //  This file implements semantic analysis for statements. | 
 | // | 
 | //===----------------------------------------------------------------------===// | 
 |  | 
 | #include "Sema.h" | 
 | #include "SemaInit.h" | 
 | #include "clang/AST/APValue.h" | 
 | #include "clang/AST/ASTContext.h" | 
 | #include "clang/AST/DeclObjC.h" | 
 | #include "clang/AST/ExprCXX.h" | 
 | #include "clang/AST/ExprObjC.h" | 
 | #include "clang/AST/StmtObjC.h" | 
 | #include "clang/AST/StmtCXX.h" | 
 | #include "clang/Lex/Preprocessor.h" | 
 | #include "clang/Basic/TargetInfo.h" | 
 | #include "llvm/ADT/STLExtras.h" | 
 | #include "llvm/ADT/SmallVector.h" | 
 | using namespace clang; | 
 |  | 
 | Sema::OwningStmtResult Sema::ActOnExprStmt(FullExprArg expr) { | 
 |   Expr *E = expr->takeAs<Expr>(); | 
 |   assert(E && "ActOnExprStmt(): missing expression"); | 
 |   if (E->getType()->isObjCInterfaceType()) { | 
 |     if (LangOpts.ObjCNonFragileABI) | 
 |       Diag(E->getLocEnd(), diag::err_indirection_requires_nonfragile_object) | 
 |              << E->getType(); | 
 |     else | 
 |       Diag(E->getLocEnd(), diag::err_direct_interface_unsupported) | 
 |              << E->getType(); | 
 |     return StmtError(); | 
 |   } | 
 |   // C99 6.8.3p2: The expression in an expression statement is evaluated as a | 
 |   // void expression for its side effects.  Conversion to void allows any | 
 |   // operand, even incomplete types. | 
 |  | 
 |   // Same thing in for stmt first clause (when expr) and third clause. | 
 |   return Owned(static_cast<Stmt*>(E)); | 
 | } | 
 |  | 
 |  | 
 | Sema::OwningStmtResult Sema::ActOnNullStmt(SourceLocation SemiLoc) { | 
 |   return Owned(new (Context) NullStmt(SemiLoc)); | 
 | } | 
 |  | 
 | Sema::OwningStmtResult Sema::ActOnDeclStmt(DeclGroupPtrTy dg, | 
 |                                            SourceLocation StartLoc, | 
 |                                            SourceLocation EndLoc) { | 
 |   DeclGroupRef DG = dg.getAsVal<DeclGroupRef>(); | 
 |  | 
 |   // If we have an invalid decl, just return an error. | 
 |   if (DG.isNull()) return StmtError(); | 
 |  | 
 |   return Owned(new (Context) DeclStmt(DG, StartLoc, EndLoc)); | 
 | } | 
 |  | 
 | void Sema::ActOnForEachDeclStmt(DeclGroupPtrTy dg) { | 
 |   DeclGroupRef DG = dg.getAsVal<DeclGroupRef>(); | 
 |    | 
 |   // If we have an invalid decl, just return. | 
 |   if (DG.isNull() || !DG.isSingleDecl()) return; | 
 |   // suppress any potential 'unused variable' warning. | 
 |   DG.getSingleDecl()->setUsed(); | 
 | } | 
 |  | 
 | void Sema::DiagnoseUnusedExprResult(const Stmt *S) { | 
 |   const Expr *E = dyn_cast_or_null<Expr>(S); | 
 |   if (!E) | 
 |     return; | 
 |  | 
 |   // Ignore expressions that have void type. | 
 |   if (E->getType()->isVoidType()) | 
 |     return; | 
 |  | 
 |   SourceLocation Loc; | 
 |   SourceRange R1, R2; | 
 |   if (!E->isUnusedResultAWarning(Loc, R1, R2, Context)) | 
 |     return; | 
 |  | 
 |   // Okay, we have an unused result.  Depending on what the base expression is, | 
 |   // we might want to make a more specific diagnostic.  Check for one of these | 
 |   // cases now. | 
 |   unsigned DiagID = diag::warn_unused_expr; | 
 |   E = E->IgnoreParens(); | 
 |   if (isa<ObjCImplicitSetterGetterRefExpr>(E)) | 
 |     DiagID = diag::warn_unused_property_expr; | 
 |    | 
 |   if (const CallExpr *CE = dyn_cast<CallExpr>(E)) { | 
 |     // If the callee has attribute pure, const, or warn_unused_result, warn with | 
 |     // a more specific message to make it clear what is happening. | 
 |     if (const Decl *FD = CE->getCalleeDecl()) { | 
 |       if (FD->getAttr<WarnUnusedResultAttr>()) { | 
 |         Diag(Loc, diag::warn_unused_call) << R1 << R2 << "warn_unused_result"; | 
 |         return; | 
 |       } | 
 |       if (FD->getAttr<PureAttr>()) { | 
 |         Diag(Loc, diag::warn_unused_call) << R1 << R2 << "pure"; | 
 |         return; | 
 |       } | 
 |       if (FD->getAttr<ConstAttr>()) { | 
 |         Diag(Loc, diag::warn_unused_call) << R1 << R2 << "const"; | 
 |         return; | 
 |       } | 
 |     }         | 
 |   } | 
 |  | 
 |   Diag(Loc, DiagID) << R1 << R2; | 
 | } | 
 |  | 
 | Action::OwningStmtResult | 
 | Sema::ActOnCompoundStmt(SourceLocation L, SourceLocation R, | 
 |                         MultiStmtArg elts, bool isStmtExpr) { | 
 |   unsigned NumElts = elts.size(); | 
 |   Stmt **Elts = reinterpret_cast<Stmt**>(elts.release()); | 
 |   // If we're in C89 mode, check that we don't have any decls after stmts.  If | 
 |   // so, emit an extension diagnostic. | 
 |   if (!getLangOptions().C99 && !getLangOptions().CPlusPlus) { | 
 |     // Note that __extension__ can be around a decl. | 
 |     unsigned i = 0; | 
 |     // Skip over all declarations. | 
 |     for (; i != NumElts && isa<DeclStmt>(Elts[i]); ++i) | 
 |       /*empty*/; | 
 |  | 
 |     // We found the end of the list or a statement.  Scan for another declstmt. | 
 |     for (; i != NumElts && !isa<DeclStmt>(Elts[i]); ++i) | 
 |       /*empty*/; | 
 |  | 
 |     if (i != NumElts) { | 
 |       Decl *D = *cast<DeclStmt>(Elts[i])->decl_begin(); | 
 |       Diag(D->getLocation(), diag::ext_mixed_decls_code); | 
 |     } | 
 |   } | 
 |   // Warn about unused expressions in statements. | 
 |   for (unsigned i = 0; i != NumElts; ++i) { | 
 |     // Ignore statements that are last in a statement expression. | 
 |     if (isStmtExpr && i == NumElts - 1) | 
 |       continue; | 
 |  | 
 |     DiagnoseUnusedExprResult(Elts[i]); | 
 |   } | 
 |  | 
 |   return Owned(new (Context) CompoundStmt(Context, Elts, NumElts, L, R)); | 
 | } | 
 |  | 
 | Action::OwningStmtResult | 
 | Sema::ActOnCaseStmt(SourceLocation CaseLoc, ExprArg lhsval, | 
 |                     SourceLocation DotDotDotLoc, ExprArg rhsval, | 
 |                     SourceLocation ColonLoc) { | 
 |   assert((lhsval.get() != 0) && "missing expression in case statement"); | 
 |  | 
 |   // C99 6.8.4.2p3: The expression shall be an integer constant. | 
 |   // However, GCC allows any evaluatable integer expression. | 
 |   Expr *LHSVal = static_cast<Expr*>(lhsval.get()); | 
 |   if (!LHSVal->isTypeDependent() && !LHSVal->isValueDependent() && | 
 |       VerifyIntegerConstantExpression(LHSVal)) | 
 |     return StmtError(); | 
 |  | 
 |   // GCC extension: The expression shall be an integer constant. | 
 |  | 
 |   Expr *RHSVal = static_cast<Expr*>(rhsval.get()); | 
 |   if (RHSVal && !RHSVal->isTypeDependent() && !RHSVal->isValueDependent() && | 
 |       VerifyIntegerConstantExpression(RHSVal)) { | 
 |     RHSVal = 0;  // Recover by just forgetting about it. | 
 |     rhsval = 0; | 
 |   } | 
 |  | 
 |   if (getSwitchStack().empty()) { | 
 |     Diag(CaseLoc, diag::err_case_not_in_switch); | 
 |     return StmtError(); | 
 |   } | 
 |  | 
 |   // Only now release the smart pointers. | 
 |   lhsval.release(); | 
 |   rhsval.release(); | 
 |   CaseStmt *CS = new (Context) CaseStmt(LHSVal, RHSVal, CaseLoc, DotDotDotLoc, | 
 |                                         ColonLoc); | 
 |   getSwitchStack().back()->addSwitchCase(CS); | 
 |   return Owned(CS); | 
 | } | 
 |  | 
 | /// ActOnCaseStmtBody - This installs a statement as the body of a case. | 
 | void Sema::ActOnCaseStmtBody(StmtTy *caseStmt, StmtArg subStmt) { | 
 |   CaseStmt *CS = static_cast<CaseStmt*>(caseStmt); | 
 |   Stmt *SubStmt = subStmt.takeAs<Stmt>(); | 
 |   CS->setSubStmt(SubStmt); | 
 | } | 
 |  | 
 | Action::OwningStmtResult | 
 | Sema::ActOnDefaultStmt(SourceLocation DefaultLoc, SourceLocation ColonLoc, | 
 |                        StmtArg subStmt, Scope *CurScope) { | 
 |   Stmt *SubStmt = subStmt.takeAs<Stmt>(); | 
 |  | 
 |   if (getSwitchStack().empty()) { | 
 |     Diag(DefaultLoc, diag::err_default_not_in_switch); | 
 |     return Owned(SubStmt); | 
 |   } | 
 |  | 
 |   DefaultStmt *DS = new (Context) DefaultStmt(DefaultLoc, ColonLoc, SubStmt); | 
 |   getSwitchStack().back()->addSwitchCase(DS); | 
 |   return Owned(DS); | 
 | } | 
 |  | 
 | Action::OwningStmtResult | 
 | Sema::ActOnLabelStmt(SourceLocation IdentLoc, IdentifierInfo *II, | 
 |                      SourceLocation ColonLoc, StmtArg subStmt) { | 
 |   Stmt *SubStmt = subStmt.takeAs<Stmt>(); | 
 |   // Look up the record for this label identifier. | 
 |   LabelStmt *&LabelDecl = getLabelMap()[II]; | 
 |  | 
 |   // If not forward referenced or defined already, just create a new LabelStmt. | 
 |   if (LabelDecl == 0) | 
 |     return Owned(LabelDecl = new (Context) LabelStmt(IdentLoc, II, SubStmt)); | 
 |  | 
 |   assert(LabelDecl->getID() == II && "Label mismatch!"); | 
 |  | 
 |   // Otherwise, this label was either forward reference or multiply defined.  If | 
 |   // multiply defined, reject it now. | 
 |   if (LabelDecl->getSubStmt()) { | 
 |     Diag(IdentLoc, diag::err_redefinition_of_label) << LabelDecl->getID(); | 
 |     Diag(LabelDecl->getIdentLoc(), diag::note_previous_definition); | 
 |     return Owned(SubStmt); | 
 |   } | 
 |  | 
 |   // Otherwise, this label was forward declared, and we just found its real | 
 |   // definition.  Fill in the forward definition and return it. | 
 |   LabelDecl->setIdentLoc(IdentLoc); | 
 |   LabelDecl->setSubStmt(SubStmt); | 
 |   return Owned(LabelDecl); | 
 | } | 
 |  | 
 | Action::OwningStmtResult | 
 | Sema::ActOnIfStmt(SourceLocation IfLoc, FullExprArg CondVal, DeclPtrTy CondVar, | 
 |                   StmtArg ThenVal, SourceLocation ElseLoc, | 
 |                   StmtArg ElseVal) { | 
 |   OwningExprResult CondResult(CondVal.release()); | 
 |  | 
 |   VarDecl *ConditionVar = 0; | 
 |   if (CondVar.get()) { | 
 |     ConditionVar = CondVar.getAs<VarDecl>(); | 
 |     CondResult = CheckConditionVariable(ConditionVar); | 
 |     if (CondResult.isInvalid()) | 
 |       return StmtError(); | 
 |   } | 
 |   Expr *ConditionExpr = CondResult.takeAs<Expr>(); | 
 |   if (!ConditionExpr) | 
 |     return StmtError(); | 
 |    | 
 |   if (CheckBooleanCondition(ConditionExpr, IfLoc)) { | 
 |     CondResult = ConditionExpr; | 
 |     return StmtError(); | 
 |   } | 
 |  | 
 |   Stmt *thenStmt = ThenVal.takeAs<Stmt>(); | 
 |   DiagnoseUnusedExprResult(thenStmt); | 
 |  | 
 |   // Warn if the if block has a null body without an else value. | 
 |   // this helps prevent bugs due to typos, such as | 
 |   // if (condition); | 
 |   //   do_stuff(); | 
 |   if (!ElseVal.get()) { | 
 |     if (NullStmt* stmt = dyn_cast<NullStmt>(thenStmt)) | 
 |       Diag(stmt->getSemiLoc(), diag::warn_empty_if_body); | 
 |   } | 
 |  | 
 |   Stmt *elseStmt = ElseVal.takeAs<Stmt>(); | 
 |   DiagnoseUnusedExprResult(elseStmt); | 
 |  | 
 |   CondResult.release(); | 
 |   return Owned(new (Context) IfStmt(IfLoc, ConditionVar, ConditionExpr,  | 
 |                                     thenStmt, ElseLoc, elseStmt)); | 
 | } | 
 |  | 
 | Action::OwningStmtResult | 
 | Sema::ActOnStartOfSwitchStmt(FullExprArg cond, DeclPtrTy CondVar) { | 
 |   OwningExprResult CondResult(cond.release()); | 
 |    | 
 |   VarDecl *ConditionVar = 0; | 
 |   if (CondVar.get()) { | 
 |     ConditionVar = CondVar.getAs<VarDecl>(); | 
 |     CondResult = CheckConditionVariable(ConditionVar); | 
 |     if (CondResult.isInvalid()) | 
 |       return StmtError(); | 
 |   } | 
 |   SwitchStmt *SS = new (Context) SwitchStmt(ConditionVar,  | 
 |                                             CondResult.takeAs<Expr>()); | 
 |   getSwitchStack().push_back(SS); | 
 |   return Owned(SS); | 
 | } | 
 |  | 
 | /// ConvertIntegerToTypeWarnOnOverflow - Convert the specified APInt to have | 
 | /// the specified width and sign.  If an overflow occurs, detect it and emit | 
 | /// the specified diagnostic. | 
 | void Sema::ConvertIntegerToTypeWarnOnOverflow(llvm::APSInt &Val, | 
 |                                               unsigned NewWidth, bool NewSign, | 
 |                                               SourceLocation Loc, | 
 |                                               unsigned DiagID) { | 
 |   // Perform a conversion to the promoted condition type if needed. | 
 |   if (NewWidth > Val.getBitWidth()) { | 
 |     // If this is an extension, just do it. | 
 |     llvm::APSInt OldVal(Val); | 
 |     Val.extend(NewWidth); | 
 |  | 
 |     // If the input was signed and negative and the output is unsigned, | 
 |     // warn. | 
 |     if (!NewSign && OldVal.isSigned() && OldVal.isNegative()) | 
 |       Diag(Loc, DiagID) << OldVal.toString(10) << Val.toString(10); | 
 |  | 
 |     Val.setIsSigned(NewSign); | 
 |   } else if (NewWidth < Val.getBitWidth()) { | 
 |     // If this is a truncation, check for overflow. | 
 |     llvm::APSInt ConvVal(Val); | 
 |     ConvVal.trunc(NewWidth); | 
 |     ConvVal.setIsSigned(NewSign); | 
 |     ConvVal.extend(Val.getBitWidth()); | 
 |     ConvVal.setIsSigned(Val.isSigned()); | 
 |     if (ConvVal != Val) | 
 |       Diag(Loc, DiagID) << Val.toString(10) << ConvVal.toString(10); | 
 |  | 
 |     // Regardless of whether a diagnostic was emitted, really do the | 
 |     // truncation. | 
 |     Val.trunc(NewWidth); | 
 |     Val.setIsSigned(NewSign); | 
 |   } else if (NewSign != Val.isSigned()) { | 
 |     // Convert the sign to match the sign of the condition.  This can cause | 
 |     // overflow as well: unsigned(INTMIN) | 
 |     llvm::APSInt OldVal(Val); | 
 |     Val.setIsSigned(NewSign); | 
 |  | 
 |     if (Val.isNegative())  // Sign bit changes meaning. | 
 |       Diag(Loc, DiagID) << OldVal.toString(10) << Val.toString(10); | 
 |   } | 
 | } | 
 |  | 
 | namespace { | 
 |   struct CaseCompareFunctor { | 
 |     bool operator()(const std::pair<llvm::APSInt, CaseStmt*> &LHS, | 
 |                     const llvm::APSInt &RHS) { | 
 |       return LHS.first < RHS; | 
 |     } | 
 |     bool operator()(const std::pair<llvm::APSInt, CaseStmt*> &LHS, | 
 |                     const std::pair<llvm::APSInt, CaseStmt*> &RHS) { | 
 |       return LHS.first < RHS.first; | 
 |     } | 
 |     bool operator()(const llvm::APSInt &LHS, | 
 |                     const std::pair<llvm::APSInt, CaseStmt*> &RHS) { | 
 |       return LHS < RHS.first; | 
 |     } | 
 |   }; | 
 | } | 
 |  | 
 | /// CmpCaseVals - Comparison predicate for sorting case values. | 
 | /// | 
 | static bool CmpCaseVals(const std::pair<llvm::APSInt, CaseStmt*>& lhs, | 
 |                         const std::pair<llvm::APSInt, CaseStmt*>& rhs) { | 
 |   if (lhs.first < rhs.first) | 
 |     return true; | 
 |  | 
 |   if (lhs.first == rhs.first && | 
 |       lhs.second->getCaseLoc().getRawEncoding() | 
 |        < rhs.second->getCaseLoc().getRawEncoding()) | 
 |     return true; | 
 |   return false; | 
 | } | 
 |  | 
 | /// CmpEnumVals - Comparison predicate for sorting enumeration values. | 
 | /// | 
 | static bool CmpEnumVals(const std::pair<llvm::APSInt, EnumConstantDecl*>& lhs, | 
 |                         const std::pair<llvm::APSInt, EnumConstantDecl*>& rhs) | 
 | { | 
 |   return lhs.first < rhs.first; | 
 | } | 
 |  | 
 | /// EqEnumVals - Comparison preficate for uniqing enumeration values. | 
 | /// | 
 | static bool EqEnumVals(const std::pair<llvm::APSInt, EnumConstantDecl*>& lhs, | 
 |                        const std::pair<llvm::APSInt, EnumConstantDecl*>& rhs) | 
 | { | 
 |   return lhs.first == rhs.first; | 
 | } | 
 |  | 
 | /// GetTypeBeforeIntegralPromotion - Returns the pre-promotion type of | 
 | /// potentially integral-promoted expression @p expr. | 
 | static QualType GetTypeBeforeIntegralPromotion(const Expr* expr) { | 
 |   const ImplicitCastExpr *ImplicitCast = | 
 |       dyn_cast_or_null<ImplicitCastExpr>(expr); | 
 |   if (ImplicitCast != NULL) { | 
 |     const Expr *ExprBeforePromotion = ImplicitCast->getSubExpr(); | 
 |     QualType TypeBeforePromotion = ExprBeforePromotion->getType(); | 
 |     if (TypeBeforePromotion->isIntegralType()) { | 
 |       return TypeBeforePromotion; | 
 |     } | 
 |   } | 
 |   return expr->getType(); | 
 | } | 
 |  | 
 | /// \brief Check (and possibly convert) the condition in a switch | 
 | /// statement in C++. | 
 | static bool CheckCXXSwitchCondition(Sema &S, SourceLocation SwitchLoc, | 
 |                                     Expr *&CondExpr) { | 
 |   if (CondExpr->isTypeDependent()) | 
 |     return false; | 
 |  | 
 |   QualType CondType = CondExpr->getType(); | 
 |  | 
 |   // C++ 6.4.2.p2: | 
 |   // The condition shall be of integral type, enumeration type, or of a class | 
 |   // type for which a single conversion function to integral or enumeration | 
 |   // type exists (12.3). If the condition is of class type, the condition is | 
 |   // converted by calling that conversion function, and the result of the | 
 |   // conversion is used in place of the original condition for the remainder | 
 |   // of this section. Integral promotions are performed. | 
 |  | 
 |   // Make sure that the condition expression has a complete type, | 
 |   // otherwise we'll never find any conversions. | 
 |   if (S.RequireCompleteType(SwitchLoc, CondType, | 
 |                             PDiag(diag::err_switch_incomplete_class_type) | 
 |                               << CondExpr->getSourceRange())) | 
 |     return true; | 
 |  | 
 |   llvm::SmallVector<CXXConversionDecl *, 4> ViableConversions; | 
 |   llvm::SmallVector<CXXConversionDecl *, 4> ExplicitConversions; | 
 |   if (const RecordType *RecordTy = CondType->getAs<RecordType>()) { | 
 |     const UnresolvedSetImpl *Conversions | 
 |       = cast<CXXRecordDecl>(RecordTy->getDecl()) | 
 |                                              ->getVisibleConversionFunctions(); | 
 |     for (UnresolvedSetImpl::iterator I = Conversions->begin(), | 
 |            E = Conversions->end(); I != E; ++I) { | 
 |       if (CXXConversionDecl *Conversion = dyn_cast<CXXConversionDecl>(*I)) | 
 |         if (Conversion->getConversionType().getNonReferenceType() | 
 |               ->isIntegralType()) { | 
 |           if (Conversion->isExplicit()) | 
 |             ExplicitConversions.push_back(Conversion); | 
 |           else | 
 |           ViableConversions.push_back(Conversion); | 
 |         } | 
 |     } | 
 |  | 
 |     switch (ViableConversions.size()) { | 
 |     case 0: | 
 |       if (ExplicitConversions.size() == 1) { | 
 |         // The user probably meant to invoke the given explicit | 
 |         // conversion; use it. | 
 |         QualType ConvTy | 
 |           = ExplicitConversions[0]->getConversionType() | 
 |                         .getNonReferenceType(); | 
 |         std::string TypeStr; | 
 |         ConvTy.getAsStringInternal(TypeStr, S.Context.PrintingPolicy); | 
 |  | 
 |         S.Diag(SwitchLoc, diag::err_switch_explicit_conversion) | 
 |           << CondType << ConvTy << CondExpr->getSourceRange() | 
 |           << CodeModificationHint::CreateInsertion(CondExpr->getLocStart(), | 
 |                                          "static_cast<" + TypeStr + ">(") | 
 |           << CodeModificationHint::CreateInsertion( | 
 |                             S.PP.getLocForEndOfToken(CondExpr->getLocEnd()), | 
 |                                ")"); | 
 |         S.Diag(ExplicitConversions[0]->getLocation(), | 
 |              diag::note_switch_conversion) | 
 |           << ConvTy->isEnumeralType() << ConvTy; | 
 |  | 
 |         // If we aren't in a SFINAE context, build a call to the  | 
 |         // explicit conversion function. | 
 |         if (S.isSFINAEContext()) | 
 |           return true; | 
 |  | 
 |         CondExpr = S.BuildCXXMemberCallExpr(CondExpr, ExplicitConversions[0]); | 
 |       } | 
 |  | 
 |       // We'll complain below about a non-integral condition type. | 
 |       break; | 
 |  | 
 |     case 1: | 
 |       // Apply this conversion. | 
 |       CondExpr = S.BuildCXXMemberCallExpr(CondExpr, ViableConversions[0]); | 
 |       break; | 
 |  | 
 |     default: | 
 |       S.Diag(SwitchLoc, diag::err_switch_multiple_conversions) | 
 |         << CondType << CondExpr->getSourceRange(); | 
 |       for (unsigned I = 0, N = ViableConversions.size(); I != N; ++I) { | 
 |         QualType ConvTy | 
 |           = ViableConversions[I]->getConversionType().getNonReferenceType(); | 
 |         S.Diag(ViableConversions[I]->getLocation(), | 
 |              diag::note_switch_conversion) | 
 |           << ConvTy->isEnumeralType() << ConvTy; | 
 |       } | 
 |       return true; | 
 |     } | 
 |   }  | 
 |  | 
 |   return false; | 
 | } | 
 |  | 
 | /// ActOnSwitchBodyError - This is called if there is an error parsing the | 
 | /// body of the switch stmt instead of ActOnFinishSwitchStmt. | 
 | void Sema::ActOnSwitchBodyError(SourceLocation SwitchLoc, StmtArg Switch, | 
 |                                 StmtArg Body) { | 
 |   // Keep the switch stack balanced. | 
 |   assert(getSwitchStack().back() == (SwitchStmt*)Switch.get() && | 
 |          "switch stack missing push/pop!"); | 
 |   getSwitchStack().pop_back(); | 
 | } | 
 |  | 
 | Action::OwningStmtResult | 
 | Sema::ActOnFinishSwitchStmt(SourceLocation SwitchLoc, StmtArg Switch, | 
 |                             StmtArg Body) { | 
 |   Stmt *BodyStmt = Body.takeAs<Stmt>(); | 
 |  | 
 |   SwitchStmt *SS = getSwitchStack().back(); | 
 |   assert(SS == (SwitchStmt*)Switch.get() && "switch stack missing push/pop!"); | 
 |  | 
 |   SS->setBody(BodyStmt, SwitchLoc); | 
 |   getSwitchStack().pop_back(); | 
 |  | 
 |   if (SS->getCond() == 0) { | 
 |     SS->Destroy(Context); | 
 |     return StmtError(); | 
 |   } | 
 |      | 
 |   Expr *CondExpr = SS->getCond(); | 
 |   QualType CondTypeBeforePromotion = | 
 |       GetTypeBeforeIntegralPromotion(CondExpr); | 
 |  | 
 |   if (getLangOptions().CPlusPlus && | 
 |       CheckCXXSwitchCondition(*this, SwitchLoc, CondExpr)) | 
 |     return StmtError(); | 
 |  | 
 |   // C99 6.8.4.2p5 - Integer promotions are performed on the controlling expr. | 
 |   UsualUnaryConversions(CondExpr); | 
 |   QualType CondType = CondExpr->getType(); | 
 |   SS->setCond(CondExpr); | 
 |  | 
 |   // C++ 6.4.2.p2: | 
 |   // Integral promotions are performed (on the switch condition). | 
 |   // | 
 |   // A case value unrepresentable by the original switch condition | 
 |   // type (before the promotion) doesn't make sense, even when it can | 
 |   // be represented by the promoted type.  Therefore we need to find | 
 |   // the pre-promotion type of the switch condition. | 
 |   if (!CondExpr->isTypeDependent()) { | 
 |     if (!CondType->isIntegerType()) { // C99 6.8.4.2p1 | 
 |       Diag(SwitchLoc, diag::err_typecheck_statement_requires_integer) | 
 |           << CondType << CondExpr->getSourceRange(); | 
 |       return StmtError(); | 
 |     } | 
 |  | 
 |     if (CondTypeBeforePromotion->isBooleanType()) { | 
 |       // switch(bool_expr) {...} is often a programmer error, e.g. | 
 |       //   switch(n && mask) { ... }  // Doh - should be "n & mask". | 
 |       // One can always use an if statement instead of switch(bool_expr). | 
 |       Diag(SwitchLoc, diag::warn_bool_switch_condition) | 
 |           << CondExpr->getSourceRange(); | 
 |     } | 
 |   } | 
 |  | 
 |   // Get the bitwidth of the switched-on value before promotions.  We must | 
 |   // convert the integer case values to this width before comparison. | 
 |   bool HasDependentValue | 
 |     = CondExpr->isTypeDependent() || CondExpr->isValueDependent(); | 
 |   unsigned CondWidth | 
 |     = HasDependentValue? 0 | 
 |       : static_cast<unsigned>(Context.getTypeSize(CondTypeBeforePromotion)); | 
 |   bool CondIsSigned = CondTypeBeforePromotion->isSignedIntegerType(); | 
 |  | 
 |   // Accumulate all of the case values in a vector so that we can sort them | 
 |   // and detect duplicates.  This vector contains the APInt for the case after | 
 |   // it has been converted to the condition type. | 
 |   typedef llvm::SmallVector<std::pair<llvm::APSInt, CaseStmt*>, 64> CaseValsTy; | 
 |   CaseValsTy CaseVals; | 
 |  | 
 |   // Keep track of any GNU case ranges we see.  The APSInt is the low value. | 
 |   typedef std::vector<std::pair<llvm::APSInt, CaseStmt*> > CaseRangesTy; | 
 |   CaseRangesTy CaseRanges; | 
 |  | 
 |   DefaultStmt *TheDefaultStmt = 0; | 
 |  | 
 |   bool CaseListIsErroneous = false; | 
 |  | 
 |   for (SwitchCase *SC = SS->getSwitchCaseList(); SC && !HasDependentValue; | 
 |        SC = SC->getNextSwitchCase()) { | 
 |  | 
 |     if (DefaultStmt *DS = dyn_cast<DefaultStmt>(SC)) { | 
 |       if (TheDefaultStmt) { | 
 |         Diag(DS->getDefaultLoc(), diag::err_multiple_default_labels_defined); | 
 |         Diag(TheDefaultStmt->getDefaultLoc(), diag::note_duplicate_case_prev); | 
 |  | 
 |         // FIXME: Remove the default statement from the switch block so that | 
 |         // we'll return a valid AST.  This requires recursing down the AST and | 
 |         // finding it, not something we are set up to do right now.  For now, | 
 |         // just lop the entire switch stmt out of the AST. | 
 |         CaseListIsErroneous = true; | 
 |       } | 
 |       TheDefaultStmt = DS; | 
 |  | 
 |     } else { | 
 |       CaseStmt *CS = cast<CaseStmt>(SC); | 
 |  | 
 |       // We already verified that the expression has a i-c-e value (C99 | 
 |       // 6.8.4.2p3) - get that value now. | 
 |       Expr *Lo = CS->getLHS(); | 
 |  | 
 |       if (Lo->isTypeDependent() || Lo->isValueDependent()) { | 
 |         HasDependentValue = true; | 
 |         break; | 
 |       } | 
 |  | 
 |       llvm::APSInt LoVal = Lo->EvaluateAsInt(Context); | 
 |  | 
 |       // Convert the value to the same width/sign as the condition. | 
 |       ConvertIntegerToTypeWarnOnOverflow(LoVal, CondWidth, CondIsSigned, | 
 |                                          CS->getLHS()->getLocStart(), | 
 |                                          diag::warn_case_value_overflow); | 
 |  | 
 |       // If the LHS is not the same type as the condition, insert an implicit | 
 |       // cast. | 
 |       ImpCastExprToType(Lo, CondType, CastExpr::CK_IntegralCast); | 
 |       CS->setLHS(Lo); | 
 |  | 
 |       // If this is a case range, remember it in CaseRanges, otherwise CaseVals. | 
 |       if (CS->getRHS()) { | 
 |         if (CS->getRHS()->isTypeDependent() || | 
 |             CS->getRHS()->isValueDependent()) { | 
 |           HasDependentValue = true; | 
 |           break; | 
 |         } | 
 |         CaseRanges.push_back(std::make_pair(LoVal, CS)); | 
 |       } else | 
 |         CaseVals.push_back(std::make_pair(LoVal, CS)); | 
 |     } | 
 |   } | 
 |  | 
 |   if (!HasDependentValue) { | 
 |     // Sort all the scalar case values so we can easily detect duplicates. | 
 |     std::stable_sort(CaseVals.begin(), CaseVals.end(), CmpCaseVals); | 
 |  | 
 |     if (!CaseVals.empty()) { | 
 |       for (unsigned i = 0, e = CaseVals.size()-1; i != e; ++i) { | 
 |         if (CaseVals[i].first == CaseVals[i+1].first) { | 
 |           // If we have a duplicate, report it. | 
 |           Diag(CaseVals[i+1].second->getLHS()->getLocStart(), | 
 |                diag::err_duplicate_case) << CaseVals[i].first.toString(10); | 
 |           Diag(CaseVals[i].second->getLHS()->getLocStart(), | 
 |                diag::note_duplicate_case_prev); | 
 |           // FIXME: We really want to remove the bogus case stmt from the | 
 |           // substmt, but we have no way to do this right now. | 
 |           CaseListIsErroneous = true; | 
 |         } | 
 |       } | 
 |     } | 
 |  | 
 |     // Detect duplicate case ranges, which usually don't exist at all in | 
 |     // the first place. | 
 |     if (!CaseRanges.empty()) { | 
 |       // Sort all the case ranges by their low value so we can easily detect | 
 |       // overlaps between ranges. | 
 |       std::stable_sort(CaseRanges.begin(), CaseRanges.end()); | 
 |  | 
 |       // Scan the ranges, computing the high values and removing empty ranges. | 
 |       std::vector<llvm::APSInt> HiVals; | 
 |       for (unsigned i = 0, e = CaseRanges.size(); i != e; ++i) { | 
 |         CaseStmt *CR = CaseRanges[i].second; | 
 |         Expr *Hi = CR->getRHS(); | 
 |         llvm::APSInt HiVal = Hi->EvaluateAsInt(Context); | 
 |  | 
 |         // Convert the value to the same width/sign as the condition. | 
 |         ConvertIntegerToTypeWarnOnOverflow(HiVal, CondWidth, CondIsSigned, | 
 |                                            CR->getRHS()->getLocStart(), | 
 |                                            diag::warn_case_value_overflow); | 
 |  | 
 |         // If the LHS is not the same type as the condition, insert an implicit | 
 |         // cast. | 
 |         ImpCastExprToType(Hi, CondType, CastExpr::CK_IntegralCast); | 
 |         CR->setRHS(Hi); | 
 |  | 
 |         // If the low value is bigger than the high value, the case is empty. | 
 |         if (CaseRanges[i].first > HiVal) { | 
 |           Diag(CR->getLHS()->getLocStart(), diag::warn_case_empty_range) | 
 |             << SourceRange(CR->getLHS()->getLocStart(), | 
 |                            CR->getRHS()->getLocEnd()); | 
 |           CaseRanges.erase(CaseRanges.begin()+i); | 
 |           --i, --e; | 
 |           continue; | 
 |         } | 
 |         HiVals.push_back(HiVal); | 
 |       } | 
 |  | 
 |       // Rescan the ranges, looking for overlap with singleton values and other | 
 |       // ranges.  Since the range list is sorted, we only need to compare case | 
 |       // ranges with their neighbors. | 
 |       for (unsigned i = 0, e = CaseRanges.size(); i != e; ++i) { | 
 |         llvm::APSInt &CRLo = CaseRanges[i].first; | 
 |         llvm::APSInt &CRHi = HiVals[i]; | 
 |         CaseStmt *CR = CaseRanges[i].second; | 
 |  | 
 |         // Check to see whether the case range overlaps with any | 
 |         // singleton cases. | 
 |         CaseStmt *OverlapStmt = 0; | 
 |         llvm::APSInt OverlapVal(32); | 
 |  | 
 |         // Find the smallest value >= the lower bound.  If I is in the | 
 |         // case range, then we have overlap. | 
 |         CaseValsTy::iterator I = std::lower_bound(CaseVals.begin(), | 
 |                                                   CaseVals.end(), CRLo, | 
 |                                                   CaseCompareFunctor()); | 
 |         if (I != CaseVals.end() && I->first < CRHi) { | 
 |           OverlapVal  = I->first;   // Found overlap with scalar. | 
 |           OverlapStmt = I->second; | 
 |         } | 
 |  | 
 |         // Find the smallest value bigger than the upper bound. | 
 |         I = std::upper_bound(I, CaseVals.end(), CRHi, CaseCompareFunctor()); | 
 |         if (I != CaseVals.begin() && (I-1)->first >= CRLo) { | 
 |           OverlapVal  = (I-1)->first;      // Found overlap with scalar. | 
 |           OverlapStmt = (I-1)->second; | 
 |         } | 
 |  | 
 |         // Check to see if this case stmt overlaps with the subsequent | 
 |         // case range. | 
 |         if (i && CRLo <= HiVals[i-1]) { | 
 |           OverlapVal  = HiVals[i-1];       // Found overlap with range. | 
 |           OverlapStmt = CaseRanges[i-1].second; | 
 |         } | 
 |  | 
 |         if (OverlapStmt) { | 
 |           // If we have a duplicate, report it. | 
 |           Diag(CR->getLHS()->getLocStart(), diag::err_duplicate_case) | 
 |             << OverlapVal.toString(10); | 
 |           Diag(OverlapStmt->getLHS()->getLocStart(), | 
 |                diag::note_duplicate_case_prev); | 
 |           // FIXME: We really want to remove the bogus case stmt from the | 
 |           // substmt, but we have no way to do this right now. | 
 |           CaseListIsErroneous = true; | 
 |         } | 
 |       } | 
 |     } | 
 |  | 
 |     // Check to see if switch is over an Enum and handles all of its  | 
 |     // values   | 
 |     const EnumType* ET = dyn_cast<EnumType>(CondTypeBeforePromotion); | 
 |     // If switch has default case, then ignore it. | 
 |     if (!CaseListIsErroneous && !TheDefaultStmt && ET) { | 
 |       const EnumDecl *ED = ET->getDecl(); | 
 |       typedef llvm::SmallVector<std::pair<llvm::APSInt, EnumConstantDecl*>, 64> EnumValsTy; | 
 |       EnumValsTy EnumVals; | 
 |  | 
 |       // Gather all enum values, set their type and sort them, allowing easier comparison  | 
 |       // with CaseVals. | 
 |       for (EnumDecl::enumerator_iterator EDI = ED->enumerator_begin(); EDI != ED->enumerator_end(); EDI++) { | 
 |         llvm::APSInt Val = (*EDI)->getInitVal(); | 
 |         if(Val.getBitWidth() < CondWidth) | 
 |           Val.extend(CondWidth); | 
 |         Val.setIsSigned(CondIsSigned); | 
 |         EnumVals.push_back(std::make_pair(Val, (*EDI))); | 
 |       } | 
 |       std::stable_sort(EnumVals.begin(), EnumVals.end(), CmpEnumVals); | 
 |       EnumValsTy::iterator EIend = std::unique(EnumVals.begin(), EnumVals.end(), EqEnumVals); | 
 |       // See which case values aren't in enum  | 
 |       EnumValsTy::const_iterator EI = EnumVals.begin(); | 
 |       for (CaseValsTy::const_iterator CI = CaseVals.begin(); CI != CaseVals.end(); CI++) { | 
 |         while (EI != EIend && EI->first < CI->first) | 
 |           EI++; | 
 |         if (EI == EIend || EI->first > CI->first) | 
 |             Diag(CI->second->getLHS()->getExprLoc(), diag::not_in_enum) << ED->getDeclName(); | 
 |       } | 
 |       // See which of case ranges aren't in enum | 
 |       EI = EnumVals.begin(); | 
 |       for (CaseRangesTy::const_iterator RI = CaseRanges.begin(); RI != CaseRanges.end() && EI != EIend; RI++) { | 
 |         while (EI != EIend && EI->first < RI->first) | 
 |           EI++; | 
 |          | 
 |         if (EI == EIend || EI->first != RI->first) { | 
 |           Diag(RI->second->getLHS()->getExprLoc(), diag::not_in_enum) << ED->getDeclName(); | 
 |         } | 
 |  | 
 |         llvm::APSInt Hi = RI->second->getRHS()->EvaluateAsInt(Context); | 
 |         while (EI != EIend && EI->first < Hi) | 
 |           EI++; | 
 |         if (EI == EIend || EI->first != Hi) | 
 |           Diag(RI->second->getRHS()->getExprLoc(), diag::not_in_enum) << ED->getDeclName(); | 
 |       } | 
 |       //Check which enum vals aren't in switch | 
 |       CaseValsTy::const_iterator CI = CaseVals.begin(); | 
 |       CaseRangesTy::const_iterator RI = CaseRanges.begin(); | 
 |       EI = EnumVals.begin(); | 
 |       for (; EI != EIend; EI++) { | 
 |         //Drop unneeded case values | 
 |         llvm::APSInt CIVal; | 
 |         while (CI != CaseVals.end() && CI->first < EI->first) | 
 |           CI++; | 
 |          | 
 |         if (CI != CaseVals.end() && CI->first == EI->first) | 
 |           continue; | 
 |  | 
 |         //Drop unneeded case ranges | 
 |         for (; RI != CaseRanges.end(); RI++) { | 
 |           llvm::APSInt Hi = RI->second->getRHS()->EvaluateAsInt(Context); | 
 |           if (EI->first <= Hi) | 
 |             break; | 
 |         } | 
 |  | 
 |         if (RI == CaseRanges.end() || EI->first < RI->first) | 
 |           Diag(CondExpr->getExprLoc(), diag::warn_missing_cases) << EI->second->getDeclName(); | 
 |       } | 
 |     } | 
 |   } | 
 |  | 
 |   // FIXME: If the case list was broken is some way, we don't have a good system | 
 |   // to patch it up.  Instead, just return the whole substmt as broken. | 
 |   if (CaseListIsErroneous) | 
 |     return StmtError(); | 
 |  | 
 |   Switch.release(); | 
 |   return Owned(SS); | 
 | } | 
 |  | 
 | Action::OwningStmtResult | 
 | Sema::ActOnWhileStmt(SourceLocation WhileLoc, FullExprArg Cond,  | 
 |                      DeclPtrTy CondVar, StmtArg Body) { | 
 |   OwningExprResult CondResult(Cond.release()); | 
 |    | 
 |   VarDecl *ConditionVar = 0; | 
 |   if (CondVar.get()) { | 
 |     ConditionVar = CondVar.getAs<VarDecl>(); | 
 |     CondResult = CheckConditionVariable(ConditionVar); | 
 |     if (CondResult.isInvalid()) | 
 |       return StmtError(); | 
 |   } | 
 |   Expr *ConditionExpr = CondResult.takeAs<Expr>(); | 
 |   if (!ConditionExpr) | 
 |     return StmtError(); | 
 |    | 
 |   if (CheckBooleanCondition(ConditionExpr, WhileLoc)) { | 
 |     CondResult = ConditionExpr; | 
 |     return StmtError(); | 
 |   } | 
 |  | 
 |   Stmt *bodyStmt = Body.takeAs<Stmt>(); | 
 |   DiagnoseUnusedExprResult(bodyStmt); | 
 |  | 
 |   CondResult.release(); | 
 |   return Owned(new (Context) WhileStmt(ConditionVar, ConditionExpr, bodyStmt,  | 
 |                                        WhileLoc)); | 
 | } | 
 |  | 
 | Action::OwningStmtResult | 
 | Sema::ActOnDoStmt(SourceLocation DoLoc, StmtArg Body, | 
 |                   SourceLocation WhileLoc, SourceLocation CondLParen, | 
 |                   ExprArg Cond, SourceLocation CondRParen) { | 
 |   Expr *condExpr = Cond.takeAs<Expr>(); | 
 |   assert(condExpr && "ActOnDoStmt(): missing expression"); | 
 |  | 
 |   if (CheckBooleanCondition(condExpr, DoLoc)) { | 
 |     Cond = condExpr; | 
 |     return StmtError(); | 
 |   } | 
 |  | 
 |   Stmt *bodyStmt = Body.takeAs<Stmt>(); | 
 |   DiagnoseUnusedExprResult(bodyStmt); | 
 |  | 
 |   Cond.release(); | 
 |   return Owned(new (Context) DoStmt(bodyStmt, condExpr, DoLoc, | 
 |                                     WhileLoc, CondRParen)); | 
 | } | 
 |  | 
 | Action::OwningStmtResult | 
 | Sema::ActOnForStmt(SourceLocation ForLoc, SourceLocation LParenLoc, | 
 |                    StmtArg first, FullExprArg second, DeclPtrTy secondVar, | 
 |                    FullExprArg third, | 
 |                    SourceLocation RParenLoc, StmtArg body) { | 
 |   Stmt *First  = static_cast<Stmt*>(first.get()); | 
 |  | 
 |   if (!getLangOptions().CPlusPlus) { | 
 |     if (DeclStmt *DS = dyn_cast_or_null<DeclStmt>(First)) { | 
 |       // C99 6.8.5p3: The declaration part of a 'for' statement shall only | 
 |       // declare identifiers for objects having storage class 'auto' or | 
 |       // 'register'. | 
 |       for (DeclStmt::decl_iterator DI=DS->decl_begin(), DE=DS->decl_end(); | 
 |            DI!=DE; ++DI) { | 
 |         VarDecl *VD = dyn_cast<VarDecl>(*DI); | 
 |         if (VD && VD->isBlockVarDecl() && !VD->hasLocalStorage()) | 
 |           VD = 0; | 
 |         if (VD == 0) | 
 |           Diag((*DI)->getLocation(), diag::err_non_variable_decl_in_for); | 
 |         // FIXME: mark decl erroneous! | 
 |       } | 
 |     } | 
 |   } | 
 |  | 
 |   OwningExprResult SecondResult(second.release()); | 
 |   VarDecl *ConditionVar = 0; | 
 |   if (secondVar.get()) { | 
 |     ConditionVar = secondVar.getAs<VarDecl>(); | 
 |     SecondResult = CheckConditionVariable(ConditionVar); | 
 |     if (SecondResult.isInvalid()) | 
 |       return StmtError(); | 
 |   } | 
 |    | 
 |   Expr *Second = SecondResult.takeAs<Expr>(); | 
 |   if (Second && CheckBooleanCondition(Second, ForLoc)) { | 
 |     SecondResult = Second; | 
 |     return StmtError(); | 
 |   } | 
 |  | 
 |   Expr *Third  = third.release().takeAs<Expr>(); | 
 |   Stmt *Body  = static_cast<Stmt*>(body.get()); | 
 |    | 
 |   DiagnoseUnusedExprResult(First); | 
 |   DiagnoseUnusedExprResult(Third); | 
 |   DiagnoseUnusedExprResult(Body); | 
 |  | 
 |   first.release(); | 
 |   body.release(); | 
 |   return Owned(new (Context) ForStmt(First, Second, ConditionVar, Third, Body,  | 
 |                                      ForLoc, LParenLoc, RParenLoc)); | 
 | } | 
 |  | 
 | Action::OwningStmtResult | 
 | Sema::ActOnObjCForCollectionStmt(SourceLocation ForLoc, | 
 |                                  SourceLocation LParenLoc, | 
 |                                  StmtArg first, ExprArg second, | 
 |                                  SourceLocation RParenLoc, StmtArg body) { | 
 |   Stmt *First  = static_cast<Stmt*>(first.get()); | 
 |   Expr *Second = static_cast<Expr*>(second.get()); | 
 |   Stmt *Body  = static_cast<Stmt*>(body.get()); | 
 |   if (First) { | 
 |     QualType FirstType; | 
 |     if (DeclStmt *DS = dyn_cast<DeclStmt>(First)) { | 
 |       if (!DS->isSingleDecl()) | 
 |         return StmtError(Diag((*DS->decl_begin())->getLocation(), | 
 |                          diag::err_toomany_element_decls)); | 
 |  | 
 |       Decl *D = DS->getSingleDecl(); | 
 |       FirstType = cast<ValueDecl>(D)->getType(); | 
 |       // C99 6.8.5p3: The declaration part of a 'for' statement shall only | 
 |       // declare identifiers for objects having storage class 'auto' or | 
 |       // 'register'. | 
 |       VarDecl *VD = cast<VarDecl>(D); | 
 |       if (VD->isBlockVarDecl() && !VD->hasLocalStorage()) | 
 |         return StmtError(Diag(VD->getLocation(), | 
 |                               diag::err_non_variable_decl_in_for)); | 
 |     } else { | 
 |       if (cast<Expr>(First)->isLvalue(Context) != Expr::LV_Valid) | 
 |         return StmtError(Diag(First->getLocStart(), | 
 |                    diag::err_selector_element_not_lvalue) | 
 |           << First->getSourceRange()); | 
 |  | 
 |       FirstType = static_cast<Expr*>(First)->getType(); | 
 |     } | 
 |     if (!FirstType->isObjCObjectPointerType() && | 
 |         !FirstType->isBlockPointerType()) | 
 |         Diag(ForLoc, diag::err_selector_element_type) | 
 |           << FirstType << First->getSourceRange(); | 
 |   } | 
 |   if (Second) { | 
 |     DefaultFunctionArrayLvalueConversion(Second); | 
 |     QualType SecondType = Second->getType(); | 
 |     if (!SecondType->isObjCObjectPointerType()) | 
 |       Diag(ForLoc, diag::err_collection_expr_type) | 
 |         << SecondType << Second->getSourceRange(); | 
 |   } | 
 |   first.release(); | 
 |   second.release(); | 
 |   body.release(); | 
 |   return Owned(new (Context) ObjCForCollectionStmt(First, Second, Body, | 
 |                                                    ForLoc, RParenLoc)); | 
 | } | 
 |  | 
 | Action::OwningStmtResult | 
 | Sema::ActOnGotoStmt(SourceLocation GotoLoc, SourceLocation LabelLoc, | 
 |                     IdentifierInfo *LabelII) { | 
 |   // Look up the record for this label identifier. | 
 |   LabelStmt *&LabelDecl = getLabelMap()[LabelII]; | 
 |  | 
 |   // If we haven't seen this label yet, create a forward reference. | 
 |   if (LabelDecl == 0) | 
 |     LabelDecl = new (Context) LabelStmt(LabelLoc, LabelII, 0); | 
 |  | 
 |   return Owned(new (Context) GotoStmt(LabelDecl, GotoLoc, LabelLoc)); | 
 | } | 
 |  | 
 | Action::OwningStmtResult | 
 | Sema::ActOnIndirectGotoStmt(SourceLocation GotoLoc, SourceLocation StarLoc, | 
 |                             ExprArg DestExp) { | 
 |   // Convert operand to void* | 
 |   Expr* E = DestExp.takeAs<Expr>(); | 
 |   if (!E->isTypeDependent()) { | 
 |     QualType ETy = E->getType(); | 
 |     QualType DestTy = Context.getPointerType(Context.VoidTy.withConst()); | 
 |     AssignConvertType ConvTy = | 
 |       CheckSingleAssignmentConstraints(DestTy, E); | 
 |     if (DiagnoseAssignmentResult(ConvTy, StarLoc, DestTy, ETy, E, AA_Passing)) | 
 |       return StmtError(); | 
 |   } | 
 |   return Owned(new (Context) IndirectGotoStmt(GotoLoc, StarLoc, E)); | 
 | } | 
 |  | 
 | Action::OwningStmtResult | 
 | Sema::ActOnContinueStmt(SourceLocation ContinueLoc, Scope *CurScope) { | 
 |   Scope *S = CurScope->getContinueParent(); | 
 |   if (!S) { | 
 |     // C99 6.8.6.2p1: A break shall appear only in or as a loop body. | 
 |     return StmtError(Diag(ContinueLoc, diag::err_continue_not_in_loop)); | 
 |   } | 
 |  | 
 |   return Owned(new (Context) ContinueStmt(ContinueLoc)); | 
 | } | 
 |  | 
 | Action::OwningStmtResult | 
 | Sema::ActOnBreakStmt(SourceLocation BreakLoc, Scope *CurScope) { | 
 |   Scope *S = CurScope->getBreakParent(); | 
 |   if (!S) { | 
 |     // C99 6.8.6.3p1: A break shall appear only in or as a switch/loop body. | 
 |     return StmtError(Diag(BreakLoc, diag::err_break_not_in_loop_or_switch)); | 
 |   } | 
 |  | 
 |   return Owned(new (Context) BreakStmt(BreakLoc)); | 
 | } | 
 |  | 
 | /// ActOnBlockReturnStmt - Utility routine to figure out block's return type. | 
 | /// | 
 | Action::OwningStmtResult | 
 | Sema::ActOnBlockReturnStmt(SourceLocation ReturnLoc, Expr *RetValExp) { | 
 |   // If this is the first return we've seen in the block, infer the type of | 
 |   // the block from it. | 
 |   if (CurBlock->ReturnType.isNull()) { | 
 |     if (RetValExp) { | 
 |       // Don't call UsualUnaryConversions(), since we don't want to do | 
 |       // integer promotions here. | 
 |       DefaultFunctionArrayLvalueConversion(RetValExp); | 
 |       CurBlock->ReturnType = RetValExp->getType(); | 
 |       if (BlockDeclRefExpr *CDRE = dyn_cast<BlockDeclRefExpr>(RetValExp)) { | 
 |         // We have to remove a 'const' added to copied-in variable which was | 
 |         // part of the implementation spec. and not the actual qualifier for | 
 |         // the variable. | 
 |         if (CDRE->isConstQualAdded()) | 
 |            CurBlock->ReturnType.removeConst(); | 
 |       } | 
 |     } else | 
 |       CurBlock->ReturnType = Context.VoidTy; | 
 |   } | 
 |   QualType FnRetType = CurBlock->ReturnType; | 
 |  | 
 |   if (CurBlock->TheDecl->hasAttr<NoReturnAttr>()) { | 
 |     Diag(ReturnLoc, diag::err_noreturn_block_has_return_expr) | 
 |       << getCurFunctionOrMethodDecl()->getDeclName(); | 
 |     return StmtError(); | 
 |   } | 
 |  | 
 |   // Otherwise, verify that this result type matches the previous one.  We are | 
 |   // pickier with blocks than for normal functions because we don't have GCC | 
 |   // compatibility to worry about here. | 
 |   if (CurBlock->ReturnType->isVoidType()) { | 
 |     if (RetValExp) { | 
 |       Diag(ReturnLoc, diag::err_return_block_has_expr); | 
 |       RetValExp->Destroy(Context); | 
 |       RetValExp = 0; | 
 |     } | 
 |     return Owned(new (Context) ReturnStmt(ReturnLoc, RetValExp)); | 
 |   } | 
 |  | 
 |   if (!RetValExp) | 
 |     return StmtError(Diag(ReturnLoc, diag::err_block_return_missing_expr)); | 
 |  | 
 |   if (!FnRetType->isDependentType() && !RetValExp->isTypeDependent()) { | 
 |     // we have a non-void block with an expression, continue checking | 
 |  | 
 |     // C99 6.8.6.4p3(136): The return statement is not an assignment. The | 
 |     // overlap restriction of subclause 6.5.16.1 does not apply to the case of | 
 |     // function return. | 
 |  | 
 |     // In C++ the return statement is handled via a copy initialization. | 
 |     // the C version of which boils down to CheckSingleAssignmentConstraints. | 
 |     OwningExprResult Res = PerformCopyInitialization( | 
 |                              InitializedEntity::InitializeResult(ReturnLoc,  | 
 |                                                                  FnRetType), | 
 |                              SourceLocation(), | 
 |                              Owned(RetValExp)); | 
 |     if (Res.isInvalid()) { | 
 |       // FIXME: Cleanup temporaries here, anyway? | 
 |       return StmtError(); | 
 |     } | 
 |      | 
 |     RetValExp = Res.takeAs<Expr>(); | 
 |     if (RetValExp)  | 
 |       CheckReturnStackAddr(RetValExp, FnRetType, ReturnLoc); | 
 |   } | 
 |  | 
 |   return Owned(new (Context) ReturnStmt(ReturnLoc, RetValExp)); | 
 | } | 
 |  | 
 | /// IsReturnCopyElidable - Whether returning @p RetExpr from a function that | 
 | /// returns a @p RetType fulfills the criteria for copy elision (C++0x 12.8p15). | 
 | static bool IsReturnCopyElidable(ASTContext &Ctx, QualType RetType, | 
 |                                  Expr *RetExpr) { | 
 |   QualType ExprType = RetExpr->getType(); | 
 |   // - in a return statement in a function with ... | 
 |   // ... a class return type ... | 
 |   if (!RetType->isRecordType()) | 
 |     return false; | 
 |   // ... the same cv-unqualified type as the function return type ... | 
 |   if (!Ctx.hasSameUnqualifiedType(RetType, ExprType)) | 
 |     return false; | 
 |   // ... the expression is the name of a non-volatile automatic object ... | 
 |   // We ignore parentheses here. | 
 |   // FIXME: Is this compliant? | 
 |   const DeclRefExpr *DR = dyn_cast<DeclRefExpr>(RetExpr->IgnoreParens()); | 
 |   if (!DR) | 
 |     return false; | 
 |   const VarDecl *VD = dyn_cast<VarDecl>(DR->getDecl()); | 
 |   if (!VD) | 
 |     return false; | 
 |   return VD->hasLocalStorage() && !VD->getType()->isReferenceType() | 
 |     && !VD->getType().isVolatileQualified(); | 
 | } | 
 |  | 
 | Action::OwningStmtResult | 
 | Sema::ActOnReturnStmt(SourceLocation ReturnLoc, ExprArg rex) { | 
 |   Expr *RetValExp = rex.takeAs<Expr>(); | 
 |   if (CurBlock) | 
 |     return ActOnBlockReturnStmt(ReturnLoc, RetValExp); | 
 |  | 
 |   QualType FnRetType; | 
 |   if (const FunctionDecl *FD = getCurFunctionDecl()) { | 
 |     FnRetType = FD->getResultType(); | 
 |     if (FD->hasAttr<NoReturnAttr>() || | 
 |         FD->getType()->getAs<FunctionType>()->getNoReturnAttr()) | 
 |       Diag(ReturnLoc, diag::warn_noreturn_function_has_return_expr) | 
 |         << getCurFunctionOrMethodDecl()->getDeclName(); | 
 |   } else if (ObjCMethodDecl *MD = getCurMethodDecl()) | 
 |     FnRetType = MD->getResultType(); | 
 |   else // If we don't have a function/method context, bail. | 
 |     return StmtError(); | 
 |  | 
 |   if (FnRetType->isVoidType()) { | 
 |     if (RetValExp && !RetValExp->isTypeDependent()) { | 
 |       // C99 6.8.6.4p1 (ext_ since GCC warns) | 
 |       unsigned D = diag::ext_return_has_expr; | 
 |       if (RetValExp->getType()->isVoidType()) | 
 |         D = diag::ext_return_has_void_expr; | 
 |  | 
 |       // return (some void expression); is legal in C++. | 
 |       if (D != diag::ext_return_has_void_expr || | 
 |           !getLangOptions().CPlusPlus) { | 
 |         NamedDecl *CurDecl = getCurFunctionOrMethodDecl(); | 
 |         Diag(ReturnLoc, D) | 
 |           << CurDecl->getDeclName() << isa<ObjCMethodDecl>(CurDecl) | 
 |           << RetValExp->getSourceRange(); | 
 |       } | 
 |  | 
 |       RetValExp = MaybeCreateCXXExprWithTemporaries(RetValExp); | 
 |     } | 
 |     return Owned(new (Context) ReturnStmt(ReturnLoc, RetValExp)); | 
 |   } | 
 |  | 
 |   if (!RetValExp && !FnRetType->isDependentType()) { | 
 |     unsigned DiagID = diag::warn_return_missing_expr;  // C90 6.6.6.4p4 | 
 |     // C99 6.8.6.4p1 (ext_ since GCC warns) | 
 |     if (getLangOptions().C99) DiagID = diag::ext_return_missing_expr; | 
 |  | 
 |     if (FunctionDecl *FD = getCurFunctionDecl()) | 
 |       Diag(ReturnLoc, DiagID) << FD->getIdentifier() << 0/*fn*/; | 
 |     else | 
 |       Diag(ReturnLoc, DiagID) << getCurMethodDecl()->getDeclName() << 1/*meth*/; | 
 |     return Owned(new (Context) ReturnStmt(ReturnLoc, (Expr*)0)); | 
 |   } | 
 |  | 
 |   if (!FnRetType->isDependentType() && !RetValExp->isTypeDependent()) { | 
 |     // we have a non-void function with an expression, continue checking | 
 |  | 
 |     // C99 6.8.6.4p3(136): The return statement is not an assignment. The | 
 |     // overlap restriction of subclause 6.5.16.1 does not apply to the case of | 
 |     // function return. | 
 |  | 
 |     // C++0x 12.8p15: When certain criteria are met, an implementation is | 
 |     //   allowed to omit the copy construction of a class object, [...] | 
 |     //   - in a return statement in a function with a class return type, when | 
 |     //     the expression is the name of a non-volatile automatic object with | 
 |     //     the same cv-unqualified type as the function return type, the copy | 
 |     //     operation can be omitted [...] | 
 |     // C++0x 12.8p16: When the criteria for elision of a copy operation are met | 
 |     //   and the object to be copied is designated by an lvalue, overload | 
 |     //   resolution to select the constructor for the copy is first performed | 
 |     //   as if the object were designated by an rvalue. | 
 |     // Note that we only compute Elidable if we're in C++0x, since we don't | 
 |     // care otherwise. | 
 |     bool Elidable = getLangOptions().CPlusPlus0x ? | 
 |                       IsReturnCopyElidable(Context, FnRetType, RetValExp) : | 
 |                       false; | 
 |     // FIXME: Elidable | 
 |     (void)Elidable; | 
 |  | 
 |     // In C++ the return statement is handled via a copy initialization. | 
 |     // the C version of which boils down to CheckSingleAssignmentConstraints. | 
 |     OwningExprResult Res = PerformCopyInitialization( | 
 |                              InitializedEntity::InitializeResult(ReturnLoc,  | 
 |                                                                  FnRetType), | 
 |                              SourceLocation(), | 
 |                              Owned(RetValExp)); | 
 |     if (Res.isInvalid()) { | 
 |       // FIXME: Cleanup temporaries here, anyway? | 
 |       return StmtError(); | 
 |     } | 
 |  | 
 |     RetValExp = Res.takeAs<Expr>(); | 
 |     if (RetValExp)  | 
 |       CheckReturnStackAddr(RetValExp, FnRetType, ReturnLoc); | 
 |   } | 
 |  | 
 |   if (RetValExp) | 
 |     RetValExp = MaybeCreateCXXExprWithTemporaries(RetValExp); | 
 |   return Owned(new (Context) ReturnStmt(ReturnLoc, RetValExp)); | 
 | } | 
 |  | 
 | /// CheckAsmLValue - GNU C has an extremely ugly extension whereby they silently | 
 | /// ignore "noop" casts in places where an lvalue is required by an inline asm. | 
 | /// We emulate this behavior when -fheinous-gnu-extensions is specified, but | 
 | /// provide a strong guidance to not use it. | 
 | /// | 
 | /// This method checks to see if the argument is an acceptable l-value and | 
 | /// returns false if it is a case we can handle. | 
 | static bool CheckAsmLValue(const Expr *E, Sema &S) { | 
 |   // Type dependent expressions will be checked during instantiation. | 
 |   if (E->isTypeDependent()) | 
 |     return false; | 
 |    | 
 |   if (E->isLvalue(S.Context) == Expr::LV_Valid) | 
 |     return false;  // Cool, this is an lvalue. | 
 |  | 
 |   // Okay, this is not an lvalue, but perhaps it is the result of a cast that we | 
 |   // are supposed to allow. | 
 |   const Expr *E2 = E->IgnoreParenNoopCasts(S.Context); | 
 |   if (E != E2 && E2->isLvalue(S.Context) == Expr::LV_Valid) { | 
 |     if (!S.getLangOptions().HeinousExtensions) | 
 |       S.Diag(E2->getLocStart(), diag::err_invalid_asm_cast_lvalue) | 
 |         << E->getSourceRange(); | 
 |     else | 
 |       S.Diag(E2->getLocStart(), diag::warn_invalid_asm_cast_lvalue) | 
 |         << E->getSourceRange(); | 
 |     // Accept, even if we emitted an error diagnostic. | 
 |     return false; | 
 |   } | 
 |  | 
 |   // None of the above, just randomly invalid non-lvalue. | 
 |   return true; | 
 | } | 
 |  | 
 |  | 
 | Sema::OwningStmtResult Sema::ActOnAsmStmt(SourceLocation AsmLoc, | 
 |                                           bool IsSimple, | 
 |                                           bool IsVolatile, | 
 |                                           unsigned NumOutputs, | 
 |                                           unsigned NumInputs, | 
 |                                           IdentifierInfo **Names, | 
 |                                           MultiExprArg constraints, | 
 |                                           MultiExprArg exprs, | 
 |                                           ExprArg asmString, | 
 |                                           MultiExprArg clobbers, | 
 |                                           SourceLocation RParenLoc, | 
 |                                           bool MSAsm) { | 
 |   unsigned NumClobbers = clobbers.size(); | 
 |   StringLiteral **Constraints = | 
 |     reinterpret_cast<StringLiteral**>(constraints.get()); | 
 |   Expr **Exprs = reinterpret_cast<Expr **>(exprs.get()); | 
 |   StringLiteral *AsmString = cast<StringLiteral>((Expr *)asmString.get()); | 
 |   StringLiteral **Clobbers = reinterpret_cast<StringLiteral**>(clobbers.get()); | 
 |  | 
 |   llvm::SmallVector<TargetInfo::ConstraintInfo, 4> OutputConstraintInfos; | 
 |  | 
 |   // The parser verifies that there is a string literal here. | 
 |   if (AsmString->isWide()) | 
 |     return StmtError(Diag(AsmString->getLocStart(),diag::err_asm_wide_character) | 
 |       << AsmString->getSourceRange()); | 
 |  | 
 |   for (unsigned i = 0; i != NumOutputs; i++) { | 
 |     StringLiteral *Literal = Constraints[i]; | 
 |     if (Literal->isWide()) | 
 |       return StmtError(Diag(Literal->getLocStart(),diag::err_asm_wide_character) | 
 |         << Literal->getSourceRange()); | 
 |  | 
 |     llvm::StringRef OutputName; | 
 |     if (Names[i]) | 
 |       OutputName = Names[i]->getName(); | 
 |  | 
 |     TargetInfo::ConstraintInfo Info(Literal->getString(), OutputName); | 
 |     if (!Context.Target.validateOutputConstraint(Info)) | 
 |       return StmtError(Diag(Literal->getLocStart(), | 
 |                             diag::err_asm_invalid_output_constraint) | 
 |                        << Info.getConstraintStr()); | 
 |  | 
 |     // Check that the output exprs are valid lvalues. | 
 |     Expr *OutputExpr = Exprs[i]; | 
 |     if (CheckAsmLValue(OutputExpr, *this)) { | 
 |       return StmtError(Diag(OutputExpr->getLocStart(), | 
 |                   diag::err_asm_invalid_lvalue_in_output) | 
 |         << OutputExpr->getSourceRange()); | 
 |     } | 
 |  | 
 |     OutputConstraintInfos.push_back(Info); | 
 |   } | 
 |  | 
 |   llvm::SmallVector<TargetInfo::ConstraintInfo, 4> InputConstraintInfos; | 
 |  | 
 |   for (unsigned i = NumOutputs, e = NumOutputs + NumInputs; i != e; i++) { | 
 |     StringLiteral *Literal = Constraints[i]; | 
 |     if (Literal->isWide()) | 
 |       return StmtError(Diag(Literal->getLocStart(),diag::err_asm_wide_character) | 
 |         << Literal->getSourceRange()); | 
 |  | 
 |     llvm::StringRef InputName; | 
 |     if (Names[i]) | 
 |       InputName = Names[i]->getName(); | 
 |  | 
 |     TargetInfo::ConstraintInfo Info(Literal->getString(), InputName); | 
 |     if (!Context.Target.validateInputConstraint(OutputConstraintInfos.data(), | 
 |                                                 NumOutputs, Info)) { | 
 |       return StmtError(Diag(Literal->getLocStart(), | 
 |                             diag::err_asm_invalid_input_constraint) | 
 |                        << Info.getConstraintStr()); | 
 |     } | 
 |  | 
 |     Expr *InputExpr = Exprs[i]; | 
 |  | 
 |     // Only allow void types for memory constraints. | 
 |     if (Info.allowsMemory() && !Info.allowsRegister()) { | 
 |       if (CheckAsmLValue(InputExpr, *this)) | 
 |         return StmtError(Diag(InputExpr->getLocStart(), | 
 |                               diag::err_asm_invalid_lvalue_in_input) | 
 |                          << Info.getConstraintStr() | 
 |                          << InputExpr->getSourceRange()); | 
 |     } | 
 |  | 
 |     if (Info.allowsRegister()) { | 
 |       if (InputExpr->getType()->isVoidType()) { | 
 |         return StmtError(Diag(InputExpr->getLocStart(), | 
 |                               diag::err_asm_invalid_type_in_input) | 
 |           << InputExpr->getType() << Info.getConstraintStr() | 
 |           << InputExpr->getSourceRange()); | 
 |       } | 
 |     } | 
 |  | 
 |     DefaultFunctionArrayLvalueConversion(Exprs[i]); | 
 |  | 
 |     InputConstraintInfos.push_back(Info); | 
 |   } | 
 |  | 
 |   // Check that the clobbers are valid. | 
 |   for (unsigned i = 0; i != NumClobbers; i++) { | 
 |     StringLiteral *Literal = Clobbers[i]; | 
 |     if (Literal->isWide()) | 
 |       return StmtError(Diag(Literal->getLocStart(),diag::err_asm_wide_character) | 
 |         << Literal->getSourceRange()); | 
 |  | 
 |     llvm::StringRef Clobber = Literal->getString(); | 
 |  | 
 |     if (!Context.Target.isValidGCCRegisterName(Clobber)) | 
 |       return StmtError(Diag(Literal->getLocStart(), | 
 |                   diag::err_asm_unknown_register_name) << Clobber); | 
 |   } | 
 |  | 
 |   constraints.release(); | 
 |   exprs.release(); | 
 |   asmString.release(); | 
 |   clobbers.release(); | 
 |   AsmStmt *NS = | 
 |     new (Context) AsmStmt(Context, AsmLoc, IsSimple, IsVolatile, MSAsm,  | 
 |                           NumOutputs, NumInputs, Names, Constraints, Exprs,  | 
 |                           AsmString, NumClobbers, Clobbers, RParenLoc); | 
 |   // Validate the asm string, ensuring it makes sense given the operands we | 
 |   // have. | 
 |   llvm::SmallVector<AsmStmt::AsmStringPiece, 8> Pieces; | 
 |   unsigned DiagOffs; | 
 |   if (unsigned DiagID = NS->AnalyzeAsmString(Pieces, Context, DiagOffs)) { | 
 |     Diag(getLocationOfStringLiteralByte(AsmString, DiagOffs), DiagID) | 
 |            << AsmString->getSourceRange(); | 
 |     DeleteStmt(NS); | 
 |     return StmtError(); | 
 |   } | 
 |  | 
 |   // Validate tied input operands for type mismatches. | 
 |   for (unsigned i = 0, e = InputConstraintInfos.size(); i != e; ++i) { | 
 |     TargetInfo::ConstraintInfo &Info = InputConstraintInfos[i]; | 
 |  | 
 |     // If this is a tied constraint, verify that the output and input have | 
 |     // either exactly the same type, or that they are int/ptr operands with the | 
 |     // same size (int/long, int*/long, are ok etc). | 
 |     if (!Info.hasTiedOperand()) continue; | 
 |  | 
 |     unsigned TiedTo = Info.getTiedOperand(); | 
 |     Expr *OutputExpr = Exprs[TiedTo]; | 
 |     Expr *InputExpr = Exprs[i+NumOutputs]; | 
 |     QualType InTy = InputExpr->getType(); | 
 |     QualType OutTy = OutputExpr->getType(); | 
 |     if (Context.hasSameType(InTy, OutTy)) | 
 |       continue;  // All types can be tied to themselves. | 
 |  | 
 |     // Int/ptr operands have some special cases that we allow. | 
 |     if ((OutTy->isIntegerType() || OutTy->isPointerType()) && | 
 |         (InTy->isIntegerType() || InTy->isPointerType())) { | 
 |  | 
 |       // They are ok if they are the same size.  Tying void* to int is ok if | 
 |       // they are the same size, for example.  This also allows tying void* to | 
 |       // int*. | 
 |       uint64_t OutSize = Context.getTypeSize(OutTy); | 
 |       uint64_t InSize = Context.getTypeSize(InTy); | 
 |       if (OutSize == InSize) | 
 |         continue; | 
 |  | 
 |       // If the smaller input/output operand is not mentioned in the asm string, | 
 |       // then we can promote it and the asm string won't notice.  Check this | 
 |       // case now. | 
 |       bool SmallerValueMentioned = false; | 
 |       for (unsigned p = 0, e = Pieces.size(); p != e; ++p) { | 
 |         AsmStmt::AsmStringPiece &Piece = Pieces[p]; | 
 |         if (!Piece.isOperand()) continue; | 
 |  | 
 |         // If this is a reference to the input and if the input was the smaller | 
 |         // one, then we have to reject this asm. | 
 |         if (Piece.getOperandNo() == i+NumOutputs) { | 
 |           if (InSize < OutSize) { | 
 |             SmallerValueMentioned = true; | 
 |             break; | 
 |           } | 
 |         } | 
 |  | 
 |         // If this is a reference to the input and if the input was the smaller | 
 |         // one, then we have to reject this asm. | 
 |         if (Piece.getOperandNo() == TiedTo) { | 
 |           if (InSize > OutSize) { | 
 |             SmallerValueMentioned = true; | 
 |             break; | 
 |           } | 
 |         } | 
 |       } | 
 |  | 
 |       // If the smaller value wasn't mentioned in the asm string, and if the | 
 |       // output was a register, just extend the shorter one to the size of the | 
 |       // larger one. | 
 |       if (!SmallerValueMentioned && | 
 |           OutputConstraintInfos[TiedTo].allowsRegister()) | 
 |         continue; | 
 |     } | 
 |  | 
 |     Diag(InputExpr->getLocStart(), | 
 |          diag::err_asm_tying_incompatible_types) | 
 |       << InTy << OutTy << OutputExpr->getSourceRange() | 
 |       << InputExpr->getSourceRange(); | 
 |     DeleteStmt(NS); | 
 |     return StmtError(); | 
 |   } | 
 |  | 
 |   return Owned(NS); | 
 | } | 
 |  | 
 | Action::OwningStmtResult | 
 | Sema::ActOnObjCAtCatchStmt(SourceLocation AtLoc, | 
 |                            SourceLocation RParen, DeclPtrTy Parm, | 
 |                            StmtArg Body, StmtArg catchList) { | 
 |   Stmt *CatchList = catchList.takeAs<Stmt>(); | 
 |   ParmVarDecl *PVD = cast_or_null<ParmVarDecl>(Parm.getAs<Decl>()); | 
 |  | 
 |   // PVD == 0 implies @catch(...). | 
 |   if (PVD) { | 
 |     // If we already know the decl is invalid, reject it. | 
 |     if (PVD->isInvalidDecl()) | 
 |       return StmtError(); | 
 |  | 
 |     if (!PVD->getType()->isObjCObjectPointerType()) | 
 |       return StmtError(Diag(PVD->getLocation(), | 
 |                        diag::err_catch_param_not_objc_type)); | 
 |     if (PVD->getType()->isObjCQualifiedIdType()) | 
 |       return StmtError(Diag(PVD->getLocation(), | 
 |                        diag::err_illegal_qualifiers_on_catch_parm)); | 
 |   } | 
 |  | 
 |   ObjCAtCatchStmt *CS = new (Context) ObjCAtCatchStmt(AtLoc, RParen, | 
 |     PVD, Body.takeAs<Stmt>(), CatchList); | 
 |   return Owned(CatchList ? CatchList : CS); | 
 | } | 
 |  | 
 | Action::OwningStmtResult | 
 | Sema::ActOnObjCAtFinallyStmt(SourceLocation AtLoc, StmtArg Body) { | 
 |   return Owned(new (Context) ObjCAtFinallyStmt(AtLoc, | 
 |                                            static_cast<Stmt*>(Body.release()))); | 
 | } | 
 |  | 
 | Action::OwningStmtResult | 
 | Sema::ActOnObjCAtTryStmt(SourceLocation AtLoc, | 
 |                          StmtArg Try, StmtArg Catch, StmtArg Finally) { | 
 |   CurFunctionNeedsScopeChecking = true; | 
 |   return Owned(new (Context) ObjCAtTryStmt(AtLoc, Try.takeAs<Stmt>(), | 
 |                                            Catch.takeAs<Stmt>(), | 
 |                                            Finally.takeAs<Stmt>())); | 
 | } | 
 |  | 
 | Action::OwningStmtResult | 
 | Sema::ActOnObjCAtThrowStmt(SourceLocation AtLoc, ExprArg expr,Scope *CurScope) { | 
 |   Expr *ThrowExpr = expr.takeAs<Expr>(); | 
 |   if (!ThrowExpr) { | 
 |     // @throw without an expression designates a rethrow (which much occur | 
 |     // in the context of an @catch clause). | 
 |     Scope *AtCatchParent = CurScope; | 
 |     while (AtCatchParent && !AtCatchParent->isAtCatchScope()) | 
 |       AtCatchParent = AtCatchParent->getParent(); | 
 |     if (!AtCatchParent) | 
 |       return StmtError(Diag(AtLoc, diag::error_rethrow_used_outside_catch)); | 
 |   } else { | 
 |     QualType ThrowType = ThrowExpr->getType(); | 
 |     // Make sure the expression type is an ObjC pointer or "void *". | 
 |     if (!ThrowType->isObjCObjectPointerType()) { | 
 |       const PointerType *PT = ThrowType->getAs<PointerType>(); | 
 |       if (!PT || !PT->getPointeeType()->isVoidType()) | 
 |         return StmtError(Diag(AtLoc, diag::error_objc_throw_expects_object) | 
 |                         << ThrowExpr->getType() << ThrowExpr->getSourceRange()); | 
 |     } | 
 |   } | 
 |   return Owned(new (Context) ObjCAtThrowStmt(AtLoc, ThrowExpr)); | 
 | } | 
 |  | 
 | Action::OwningStmtResult | 
 | Sema::ActOnObjCAtSynchronizedStmt(SourceLocation AtLoc, ExprArg SynchExpr, | 
 |                                   StmtArg SynchBody) { | 
 |   CurFunctionNeedsScopeChecking = true; | 
 |  | 
 |   // Make sure the expression type is an ObjC pointer or "void *". | 
 |   Expr *SyncExpr = static_cast<Expr*>(SynchExpr.get()); | 
 |   if (!SyncExpr->getType()->isObjCObjectPointerType()) { | 
 |     const PointerType *PT = SyncExpr->getType()->getAs<PointerType>(); | 
 |     if (!PT || !PT->getPointeeType()->isVoidType()) | 
 |       return StmtError(Diag(AtLoc, diag::error_objc_synchronized_expects_object) | 
 |                        << SyncExpr->getType() << SyncExpr->getSourceRange()); | 
 |   } | 
 |  | 
 |   return Owned(new (Context) ObjCAtSynchronizedStmt(AtLoc, | 
 |                                                     SynchExpr.takeAs<Stmt>(), | 
 |                                                     SynchBody.takeAs<Stmt>())); | 
 | } | 
 |  | 
 | /// ActOnCXXCatchBlock - Takes an exception declaration and a handler block | 
 | /// and creates a proper catch handler from them. | 
 | Action::OwningStmtResult | 
 | Sema::ActOnCXXCatchBlock(SourceLocation CatchLoc, DeclPtrTy ExDecl, | 
 |                          StmtArg HandlerBlock) { | 
 |   // There's nothing to test that ActOnExceptionDecl didn't already test. | 
 |   return Owned(new (Context) CXXCatchStmt(CatchLoc, | 
 |                                   cast_or_null<VarDecl>(ExDecl.getAs<Decl>()), | 
 |                                           HandlerBlock.takeAs<Stmt>())); | 
 | } | 
 |  | 
 | class TypeWithHandler { | 
 |   QualType t; | 
 |   CXXCatchStmt *stmt; | 
 | public: | 
 |   TypeWithHandler(const QualType &type, CXXCatchStmt *statement) | 
 |   : t(type), stmt(statement) {} | 
 |  | 
 |   // An arbitrary order is fine as long as it places identical | 
 |   // types next to each other. | 
 |   bool operator<(const TypeWithHandler &y) const { | 
 |     if (t.getAsOpaquePtr() < y.t.getAsOpaquePtr()) | 
 |       return true; | 
 |     if (t.getAsOpaquePtr() > y.t.getAsOpaquePtr()) | 
 |       return false; | 
 |     else | 
 |       return getTypeSpecStartLoc() < y.getTypeSpecStartLoc(); | 
 |   } | 
 |  | 
 |   bool operator==(const TypeWithHandler& other) const { | 
 |     return t == other.t; | 
 |   } | 
 |  | 
 |   QualType getQualType() const { return t; } | 
 |   CXXCatchStmt *getCatchStmt() const { return stmt; } | 
 |   SourceLocation getTypeSpecStartLoc() const { | 
 |     return stmt->getExceptionDecl()->getTypeSpecStartLoc(); | 
 |   } | 
 | }; | 
 |  | 
 | /// ActOnCXXTryBlock - Takes a try compound-statement and a number of | 
 | /// handlers and creates a try statement from them. | 
 | Action::OwningStmtResult | 
 | Sema::ActOnCXXTryBlock(SourceLocation TryLoc, StmtArg TryBlock, | 
 |                        MultiStmtArg RawHandlers) { | 
 |   unsigned NumHandlers = RawHandlers.size(); | 
 |   assert(NumHandlers > 0 && | 
 |          "The parser shouldn't call this if there are no handlers."); | 
 |   Stmt **Handlers = reinterpret_cast<Stmt**>(RawHandlers.get()); | 
 |  | 
 |   llvm::SmallVector<TypeWithHandler, 8> TypesWithHandlers; | 
 |  | 
 |   for (unsigned i = 0; i < NumHandlers; ++i) { | 
 |     CXXCatchStmt *Handler = llvm::cast<CXXCatchStmt>(Handlers[i]); | 
 |     if (!Handler->getExceptionDecl()) { | 
 |       if (i < NumHandlers - 1) | 
 |         return StmtError(Diag(Handler->getLocStart(), | 
 |                               diag::err_early_catch_all)); | 
 |  | 
 |       continue; | 
 |     } | 
 |  | 
 |     const QualType CaughtType = Handler->getCaughtType(); | 
 |     const QualType CanonicalCaughtType = Context.getCanonicalType(CaughtType); | 
 |     TypesWithHandlers.push_back(TypeWithHandler(CanonicalCaughtType, Handler)); | 
 |   } | 
 |  | 
 |   // Detect handlers for the same type as an earlier one. | 
 |   if (NumHandlers > 1) { | 
 |     llvm::array_pod_sort(TypesWithHandlers.begin(), TypesWithHandlers.end()); | 
 |  | 
 |     TypeWithHandler prev = TypesWithHandlers[0]; | 
 |     for (unsigned i = 1; i < TypesWithHandlers.size(); ++i) { | 
 |       TypeWithHandler curr = TypesWithHandlers[i]; | 
 |  | 
 |       if (curr == prev) { | 
 |         Diag(curr.getTypeSpecStartLoc(), | 
 |              diag::warn_exception_caught_by_earlier_handler) | 
 |           << curr.getCatchStmt()->getCaughtType().getAsString(); | 
 |         Diag(prev.getTypeSpecStartLoc(), | 
 |              diag::note_previous_exception_handler) | 
 |           << prev.getCatchStmt()->getCaughtType().getAsString(); | 
 |       } | 
 |  | 
 |       prev = curr; | 
 |     } | 
 |   } | 
 |  | 
 |   // FIXME: We should detect handlers that cannot catch anything because an | 
 |   // earlier handler catches a superclass. Need to find a method that is not | 
 |   // quadratic for this. | 
 |   // Neither of these are explicitly forbidden, but every compiler detects them | 
 |   // and warns. | 
 |  | 
 |   CurFunctionNeedsScopeChecking = true; | 
 |   RawHandlers.release(); | 
 |   return Owned(CXXTryStmt::Create(Context, TryLoc, | 
 |                                   static_cast<Stmt*>(TryBlock.release()), | 
 |                                   Handlers, NumHandlers)); | 
 | } |