| //===--- Sema.cpp - AST Builder and Semantic Analysis Implementation ------===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file implements the actions class which performs semantic analysis and |
| // builds an AST out of a parse stream. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "Sema.h" |
| #include "TargetAttributesSema.h" |
| #include "llvm/ADT/DenseMap.h" |
| #include "llvm/ADT/SmallSet.h" |
| #include "llvm/ADT/APFloat.h" |
| #include "clang/Sema/ExternalSemaSource.h" |
| #include "clang/AST/ASTConsumer.h" |
| #include "clang/AST/ASTContext.h" |
| #include "clang/AST/ASTDiagnostic.h" |
| #include "clang/AST/DeclObjC.h" |
| #include "clang/AST/Expr.h" |
| #include "clang/Lex/Preprocessor.h" |
| #include "clang/Basic/PartialDiagnostic.h" |
| #include "clang/Basic/TargetInfo.h" |
| using namespace clang; |
| |
| FunctionScopeInfo::~FunctionScopeInfo() { } |
| |
| void FunctionScopeInfo::Clear(unsigned NumErrors) { |
| HasBranchProtectedScope = false; |
| HasBranchIntoScope = false; |
| HasIndirectGoto = false; |
| |
| LabelMap.clear(); |
| SwitchStack.clear(); |
| Returns.clear(); |
| NumErrorsAtStartOfFunction = NumErrors; |
| } |
| |
| BlockScopeInfo::~BlockScopeInfo() { } |
| |
| void Sema::ActOnTranslationUnitScope(SourceLocation Loc, Scope *S) { |
| TUScope = S; |
| PushDeclContext(S, Context.getTranslationUnitDecl()); |
| |
| VAListTagName = PP.getIdentifierInfo("__va_list_tag"); |
| |
| if (!Context.isInt128Installed() && // May be set by PCHReader. |
| PP.getTargetInfo().getPointerWidth(0) >= 64) { |
| TypeSourceInfo *TInfo; |
| |
| // Install [u]int128_t for 64-bit targets. |
| TInfo = Context.getTrivialTypeSourceInfo(Context.Int128Ty); |
| PushOnScopeChains(TypedefDecl::Create(Context, CurContext, |
| SourceLocation(), |
| &Context.Idents.get("__int128_t"), |
| TInfo), TUScope); |
| |
| TInfo = Context.getTrivialTypeSourceInfo(Context.UnsignedInt128Ty); |
| PushOnScopeChains(TypedefDecl::Create(Context, CurContext, |
| SourceLocation(), |
| &Context.Idents.get("__uint128_t"), |
| TInfo), TUScope); |
| Context.setInt128Installed(); |
| } |
| |
| |
| if (!PP.getLangOptions().ObjC1) return; |
| |
| // Built-in ObjC types may already be set by PCHReader (hence isNull checks). |
| if (Context.getObjCSelType().isNull()) { |
| // Create the built-in typedef for 'SEL'. |
| QualType SelT = Context.getPointerType(Context.ObjCBuiltinSelTy); |
| TypeSourceInfo *SelInfo = Context.getTrivialTypeSourceInfo(SelT); |
| TypedefDecl *SelTypedef |
| = TypedefDecl::Create(Context, CurContext, SourceLocation(), |
| &Context.Idents.get("SEL"), SelInfo); |
| PushOnScopeChains(SelTypedef, TUScope); |
| Context.setObjCSelType(Context.getTypeDeclType(SelTypedef)); |
| Context.ObjCSelRedefinitionType = Context.getObjCSelType(); |
| } |
| |
| // Synthesize "@class Protocol; |
| if (Context.getObjCProtoType().isNull()) { |
| ObjCInterfaceDecl *ProtocolDecl = |
| ObjCInterfaceDecl::Create(Context, CurContext, SourceLocation(), |
| &Context.Idents.get("Protocol"), |
| SourceLocation(), true); |
| Context.setObjCProtoType(Context.getObjCInterfaceType(ProtocolDecl)); |
| PushOnScopeChains(ProtocolDecl, TUScope, false); |
| } |
| // Create the built-in typedef for 'id'. |
| if (Context.getObjCIdType().isNull()) { |
| QualType T = Context.getObjCObjectType(Context.ObjCBuiltinIdTy, 0, 0); |
| T = Context.getObjCObjectPointerType(T); |
| TypeSourceInfo *IdInfo = Context.getTrivialTypeSourceInfo(T); |
| TypedefDecl *IdTypedef |
| = TypedefDecl::Create(Context, CurContext, SourceLocation(), |
| &Context.Idents.get("id"), IdInfo); |
| PushOnScopeChains(IdTypedef, TUScope); |
| Context.setObjCIdType(Context.getTypeDeclType(IdTypedef)); |
| Context.ObjCIdRedefinitionType = Context.getObjCIdType(); |
| } |
| // Create the built-in typedef for 'Class'. |
| if (Context.getObjCClassType().isNull()) { |
| QualType T = Context.getObjCObjectType(Context.ObjCBuiltinClassTy, 0, 0); |
| T = Context.getObjCObjectPointerType(T); |
| TypeSourceInfo *ClassInfo = Context.getTrivialTypeSourceInfo(T); |
| TypedefDecl *ClassTypedef |
| = TypedefDecl::Create(Context, CurContext, SourceLocation(), |
| &Context.Idents.get("Class"), ClassInfo); |
| PushOnScopeChains(ClassTypedef, TUScope); |
| Context.setObjCClassType(Context.getTypeDeclType(ClassTypedef)); |
| Context.ObjCClassRedefinitionType = Context.getObjCClassType(); |
| } |
| } |
| |
| Sema::Sema(Preprocessor &pp, ASTContext &ctxt, ASTConsumer &consumer, |
| bool CompleteTranslationUnit, |
| CodeCompleteConsumer *CodeCompleter) |
| : TheTargetAttributesSema(0), |
| LangOpts(pp.getLangOptions()), PP(pp), Context(ctxt), Consumer(consumer), |
| Diags(PP.getDiagnostics()), SourceMgr(PP.getSourceManager()), |
| ExternalSource(0), CodeCompleter(CodeCompleter), CurContext(0), |
| PackContext(0), VisContext(0), TopFunctionScope(0), ParsingDeclDepth(0), |
| IdResolver(pp.getLangOptions()), GlobalNewDeleteDeclared(false), |
| CompleteTranslationUnit(CompleteTranslationUnit), |
| NumSFINAEErrors(0), SuppressAccessChecking(false), |
| NonInstantiationEntries(0), CurrentInstantiationScope(0), TyposCorrected(0), |
| AnalysisWarnings(*this) |
| { |
| TUScope = 0; |
| if (getLangOptions().CPlusPlus) |
| FieldCollector.reset(new CXXFieldCollector()); |
| |
| // Tell diagnostics how to render things from the AST library. |
| PP.getDiagnostics().SetArgToStringFn(&FormatASTNodeDiagnosticArgument, |
| &Context); |
| |
| ExprEvalContexts.push_back( |
| ExpressionEvaluationContextRecord(PotentiallyEvaluated, 0)); |
| } |
| |
| Sema::~Sema() { |
| if (PackContext) FreePackedContext(); |
| if (VisContext) FreeVisContext(); |
| delete TheTargetAttributesSema; |
| while (!FunctionScopes.empty()) |
| PopFunctionOrBlockScope(); |
| } |
| |
| /// ImpCastExprToType - If Expr is not of type 'Type', insert an implicit cast. |
| /// If there is already an implicit cast, merge into the existing one. |
| /// The result is of the given category. |
| void Sema::ImpCastExprToType(Expr *&Expr, QualType Ty, |
| CastExpr::CastKind Kind, |
| ImplicitCastExpr::ResultCategory Category, |
| CXXBaseSpecifierArray BasePath) { |
| QualType ExprTy = Context.getCanonicalType(Expr->getType()); |
| QualType TypeTy = Context.getCanonicalType(Ty); |
| |
| if (ExprTy == TypeTy) |
| return; |
| |
| if (Expr->getType()->isPointerType() && Ty->isPointerType()) { |
| QualType ExprBaseType = cast<PointerType>(ExprTy)->getPointeeType(); |
| QualType BaseType = cast<PointerType>(TypeTy)->getPointeeType(); |
| if (ExprBaseType.getAddressSpace() != BaseType.getAddressSpace()) { |
| Diag(Expr->getExprLoc(), diag::err_implicit_pointer_address_space_cast) |
| << Expr->getSourceRange(); |
| } |
| } |
| |
| // If this is a derived-to-base cast to a through a virtual base, we |
| // need a vtable. |
| if (Kind == CastExpr::CK_DerivedToBase && |
| BasePathInvolvesVirtualBase(BasePath)) { |
| QualType T = Expr->getType(); |
| if (const PointerType *Pointer = T->getAs<PointerType>()) |
| T = Pointer->getPointeeType(); |
| if (const RecordType *RecordTy = T->getAs<RecordType>()) |
| MarkVTableUsed(Expr->getLocStart(), |
| cast<CXXRecordDecl>(RecordTy->getDecl())); |
| } |
| |
| if (ImplicitCastExpr *ImpCast = dyn_cast<ImplicitCastExpr>(Expr)) { |
| if (ImpCast->getCastKind() == Kind && BasePath.empty()) { |
| ImpCast->setType(Ty); |
| ImpCast->setCategory(Category); |
| return; |
| } |
| } |
| |
| Expr = new (Context) ImplicitCastExpr(Ty, Kind, Expr, BasePath, Category); |
| } |
| |
| ImplicitCastExpr::ResultCategory Sema::CastCategory(Expr *E) { |
| Expr::Classification Classification = E->Classify(Context); |
| return Classification.isRValue() ? |
| ImplicitCastExpr::RValue : |
| (Classification.isLValue() ? |
| ImplicitCastExpr::LValue : |
| ImplicitCastExpr::XValue); |
| } |
| |
| void Sema::DeleteExpr(ExprTy *E) { |
| } |
| void Sema::DeleteStmt(StmtTy *S) { |
| } |
| |
| /// ActOnEndOfTranslationUnit - This is called at the very end of the |
| /// translation unit when EOF is reached and all but the top-level scope is |
| /// popped. |
| void Sema::ActOnEndOfTranslationUnit() { |
| // At PCH writing, implicit instantiations and VTable handling info are |
| // stored and performed when the PCH is included. |
| if (CompleteTranslationUnit) |
| while (1) { |
| // C++: Perform implicit template instantiations. |
| // |
| // FIXME: When we perform these implicit instantiations, we do not |
| // carefully keep track of the point of instantiation (C++ [temp.point]). |
| // This means that name lookup that occurs within the template |
| // instantiation will always happen at the end of the translation unit, |
| // so it will find some names that should not be found. Although this is |
| // common behavior for C++ compilers, it is technically wrong. In the |
| // future, we either need to be able to filter the results of name lookup |
| // or we need to perform template instantiations earlier. |
| PerformPendingImplicitInstantiations(); |
| |
| /// If DefinedUsedVTables ends up marking any virtual member |
| /// functions it might lead to more pending template |
| /// instantiations, which is why we need to loop here. |
| if (!DefineUsedVTables()) |
| break; |
| } |
| |
| // Remove functions that turned out to be used. |
| UnusedStaticFuncs.erase(std::remove_if(UnusedStaticFuncs.begin(), |
| UnusedStaticFuncs.end(), |
| std::bind2nd(std::mem_fun(&FunctionDecl::isUsed), |
| true)), |
| UnusedStaticFuncs.end()); |
| |
| if (!CompleteTranslationUnit) |
| return; |
| |
| // Check for #pragma weak identifiers that were never declared |
| // FIXME: This will cause diagnostics to be emitted in a non-determinstic |
| // order! Iterating over a densemap like this is bad. |
| for (llvm::DenseMap<IdentifierInfo*,WeakInfo>::iterator |
| I = WeakUndeclaredIdentifiers.begin(), |
| E = WeakUndeclaredIdentifiers.end(); I != E; ++I) { |
| if (I->second.getUsed()) continue; |
| |
| Diag(I->second.getLocation(), diag::warn_weak_identifier_undeclared) |
| << I->first; |
| } |
| |
| // C99 6.9.2p2: |
| // A declaration of an identifier for an object that has file |
| // scope without an initializer, and without a storage-class |
| // specifier or with the storage-class specifier static, |
| // constitutes a tentative definition. If a translation unit |
| // contains one or more tentative definitions for an identifier, |
| // and the translation unit contains no external definition for |
| // that identifier, then the behavior is exactly as if the |
| // translation unit contains a file scope declaration of that |
| // identifier, with the composite type as of the end of the |
| // translation unit, with an initializer equal to 0. |
| llvm::SmallSet<VarDecl *, 32> Seen; |
| for (unsigned i = 0, e = TentativeDefinitions.size(); i != e; ++i) { |
| VarDecl *VD = TentativeDefinitions[i]->getActingDefinition(); |
| |
| // If the tentative definition was completed, getActingDefinition() returns |
| // null. If we've already seen this variable before, insert()'s second |
| // return value is false. |
| if (VD == 0 || VD->isInvalidDecl() || !Seen.insert(VD)) |
| continue; |
| |
| if (const IncompleteArrayType *ArrayT |
| = Context.getAsIncompleteArrayType(VD->getType())) { |
| if (RequireCompleteType(VD->getLocation(), |
| ArrayT->getElementType(), |
| diag::err_tentative_def_incomplete_type_arr)) { |
| VD->setInvalidDecl(); |
| continue; |
| } |
| |
| // Set the length of the array to 1 (C99 6.9.2p5). |
| Diag(VD->getLocation(), diag::warn_tentative_incomplete_array); |
| llvm::APInt One(Context.getTypeSize(Context.getSizeType()), true); |
| QualType T = Context.getConstantArrayType(ArrayT->getElementType(), |
| One, ArrayType::Normal, 0); |
| VD->setType(T); |
| } else if (RequireCompleteType(VD->getLocation(), VD->getType(), |
| diag::err_tentative_def_incomplete_type)) |
| VD->setInvalidDecl(); |
| |
| // Notify the consumer that we've completed a tentative definition. |
| if (!VD->isInvalidDecl()) |
| Consumer.CompleteTentativeDefinition(VD); |
| |
| } |
| |
| // Output warning for unused functions. |
| for (std::vector<FunctionDecl*>::iterator |
| F = UnusedStaticFuncs.begin(), |
| FEnd = UnusedStaticFuncs.end(); |
| F != FEnd; |
| ++F) |
| Diag((*F)->getLocation(), diag::warn_unused_function) << (*F)->getDeclName(); |
| |
| } |
| |
| |
| //===----------------------------------------------------------------------===// |
| // Helper functions. |
| //===----------------------------------------------------------------------===// |
| |
| DeclContext *Sema::getFunctionLevelDeclContext() { |
| DeclContext *DC = CurContext; |
| |
| while (isa<BlockDecl>(DC) || isa<EnumDecl>(DC)) |
| DC = DC->getParent(); |
| |
| return DC; |
| } |
| |
| /// getCurFunctionDecl - If inside of a function body, this returns a pointer |
| /// to the function decl for the function being parsed. If we're currently |
| /// in a 'block', this returns the containing context. |
| FunctionDecl *Sema::getCurFunctionDecl() { |
| DeclContext *DC = getFunctionLevelDeclContext(); |
| return dyn_cast<FunctionDecl>(DC); |
| } |
| |
| ObjCMethodDecl *Sema::getCurMethodDecl() { |
| DeclContext *DC = getFunctionLevelDeclContext(); |
| return dyn_cast<ObjCMethodDecl>(DC); |
| } |
| |
| NamedDecl *Sema::getCurFunctionOrMethodDecl() { |
| DeclContext *DC = getFunctionLevelDeclContext(); |
| if (isa<ObjCMethodDecl>(DC) || isa<FunctionDecl>(DC)) |
| return cast<NamedDecl>(DC); |
| return 0; |
| } |
| |
| Sema::SemaDiagnosticBuilder::~SemaDiagnosticBuilder() { |
| if (!this->Emit()) |
| return; |
| |
| // If this is not a note, and we're in a template instantiation |
| // that is different from the last template instantiation where |
| // we emitted an error, print a template instantiation |
| // backtrace. |
| if (!SemaRef.Diags.isBuiltinNote(DiagID) && |
| !SemaRef.ActiveTemplateInstantiations.empty() && |
| SemaRef.ActiveTemplateInstantiations.back() |
| != SemaRef.LastTemplateInstantiationErrorContext) { |
| SemaRef.PrintInstantiationStack(); |
| SemaRef.LastTemplateInstantiationErrorContext |
| = SemaRef.ActiveTemplateInstantiations.back(); |
| } |
| } |
| |
| Sema::SemaDiagnosticBuilder Sema::Diag(SourceLocation Loc, unsigned DiagID) { |
| if (isSFINAEContext()) { |
| switch (Diagnostic::getDiagnosticSFINAEResponse(DiagID)) { |
| case Diagnostic::SFINAE_Report: |
| // Fall through; we'll report the diagnostic below. |
| break; |
| |
| case Diagnostic::SFINAE_SubstitutionFailure: |
| // Count this failure so that we know that template argument deduction |
| // has failed. |
| ++NumSFINAEErrors; |
| // Fall through |
| |
| case Diagnostic::SFINAE_Suppress: |
| // Suppress this diagnostic. |
| Diags.setLastDiagnosticIgnored(); |
| return SemaDiagnosticBuilder(*this); |
| } |
| } |
| |
| DiagnosticBuilder DB = Diags.Report(FullSourceLoc(Loc, SourceMgr), DiagID); |
| return SemaDiagnosticBuilder(DB, *this, DiagID); |
| } |
| |
| Sema::SemaDiagnosticBuilder |
| Sema::Diag(SourceLocation Loc, const PartialDiagnostic& PD) { |
| SemaDiagnosticBuilder Builder(Diag(Loc, PD.getDiagID())); |
| PD.Emit(Builder); |
| |
| return Builder; |
| } |
| |
| /// \brief Determines the active Scope associated with the given declaration |
| /// context. |
| /// |
| /// This routine maps a declaration context to the active Scope object that |
| /// represents that declaration context in the parser. It is typically used |
| /// from "scope-less" code (e.g., template instantiation, lazy creation of |
| /// declarations) that injects a name for name-lookup purposes and, therefore, |
| /// must update the Scope. |
| /// |
| /// \returns The scope corresponding to the given declaraion context, or NULL |
| /// if no such scope is open. |
| Scope *Sema::getScopeForContext(DeclContext *Ctx) { |
| |
| if (!Ctx) |
| return 0; |
| |
| Ctx = Ctx->getPrimaryContext(); |
| for (Scope *S = getCurScope(); S; S = S->getParent()) { |
| // Ignore scopes that cannot have declarations. This is important for |
| // out-of-line definitions of static class members. |
| if (S->getFlags() & (Scope::DeclScope | Scope::TemplateParamScope)) |
| if (DeclContext *Entity = static_cast<DeclContext *> (S->getEntity())) |
| if (Ctx == Entity->getPrimaryContext()) |
| return S; |
| } |
| |
| return 0; |
| } |
| |
| /// \brief Enter a new function scope |
| void Sema::PushFunctionScope() { |
| if (FunctionScopes.empty()) { |
| // Use the "top" function scope rather than having to allocate memory for |
| // a new scope. |
| TopFunctionScope.Clear(getDiagnostics().getNumErrors()); |
| FunctionScopes.push_back(&TopFunctionScope); |
| return; |
| } |
| |
| FunctionScopes.push_back( |
| new FunctionScopeInfo(getDiagnostics().getNumErrors())); |
| } |
| |
| void Sema::PushBlockScope(Scope *BlockScope, BlockDecl *Block) { |
| FunctionScopes.push_back(new BlockScopeInfo(getDiagnostics().getNumErrors(), |
| BlockScope, Block)); |
| } |
| |
| void Sema::PopFunctionOrBlockScope() { |
| if (FunctionScopes.back() != &TopFunctionScope) |
| delete FunctionScopes.back(); |
| else |
| TopFunctionScope.Clear(getDiagnostics().getNumErrors()); |
| |
| FunctionScopes.pop_back(); |
| } |
| |
| /// \brief Determine whether any errors occurred within this function/method/ |
| /// block. |
| bool Sema::hasAnyErrorsInThisFunction() const { |
| unsigned NumErrors = TopFunctionScope.NumErrorsAtStartOfFunction; |
| if (!FunctionScopes.empty()) |
| NumErrors = FunctionScopes.back()->NumErrorsAtStartOfFunction; |
| return NumErrors != getDiagnostics().getNumErrors(); |
| } |
| |
| BlockScopeInfo *Sema::getCurBlock() { |
| if (FunctionScopes.empty()) |
| return 0; |
| |
| return dyn_cast<BlockScopeInfo>(FunctionScopes.back()); |
| } |
| |
| // Pin this vtable to this file. |
| ExternalSemaSource::~ExternalSemaSource() {} |