| //===--- ModuleBuilder.cpp - Emit LLVM Code from ASTs ---------------------===// |
| // |
| // 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 |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This builds an AST and converts it to LLVM Code. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "clang/CodeGen/ModuleBuilder.h" |
| #include "CGDebugInfo.h" |
| #include "CodeGenModule.h" |
| #include "clang/AST/ASTContext.h" |
| #include "clang/AST/DeclObjC.h" |
| #include "clang/AST/Expr.h" |
| #include "clang/Basic/CodeGenOptions.h" |
| #include "clang/Basic/Diagnostic.h" |
| #include "clang/Basic/TargetInfo.h" |
| #include "llvm/ADT/StringRef.h" |
| #include "llvm/IR/DataLayout.h" |
| #include "llvm/IR/LLVMContext.h" |
| #include "llvm/IR/Module.h" |
| #include <memory> |
| |
| using namespace clang; |
| using namespace CodeGen; |
| |
| namespace { |
| class CodeGeneratorImpl : public CodeGenerator { |
| DiagnosticsEngine &Diags; |
| ASTContext *Ctx; |
| const HeaderSearchOptions &HeaderSearchOpts; // Only used for debug info. |
| const PreprocessorOptions &PreprocessorOpts; // Only used for debug info. |
| const CodeGenOptions CodeGenOpts; // Intentionally copied in. |
| |
| unsigned HandlingTopLevelDecls; |
| |
| /// Use this when emitting decls to block re-entrant decl emission. It will |
| /// emit all deferred decls on scope exit. Set EmitDeferred to false if decl |
| /// emission must be deferred longer, like at the end of a tag definition. |
| struct HandlingTopLevelDeclRAII { |
| CodeGeneratorImpl &Self; |
| bool EmitDeferred; |
| HandlingTopLevelDeclRAII(CodeGeneratorImpl &Self, |
| bool EmitDeferred = true) |
| : Self(Self), EmitDeferred(EmitDeferred) { |
| ++Self.HandlingTopLevelDecls; |
| } |
| ~HandlingTopLevelDeclRAII() { |
| unsigned Level = --Self.HandlingTopLevelDecls; |
| if (Level == 0 && EmitDeferred) |
| Self.EmitDeferredDecls(); |
| } |
| }; |
| |
| CoverageSourceInfo *CoverageInfo; |
| |
| protected: |
| std::unique_ptr<llvm::Module> M; |
| std::unique_ptr<CodeGen::CodeGenModule> Builder; |
| |
| private: |
| SmallVector<FunctionDecl *, 8> DeferredInlineMemberFuncDefs; |
| |
| static llvm::StringRef ExpandModuleName(llvm::StringRef ModuleName, |
| const CodeGenOptions &CGO) { |
| if (ModuleName == "-" && !CGO.MainFileName.empty()) |
| return CGO.MainFileName; |
| return ModuleName; |
| } |
| |
| public: |
| CodeGeneratorImpl(DiagnosticsEngine &diags, llvm::StringRef ModuleName, |
| const HeaderSearchOptions &HSO, |
| const PreprocessorOptions &PPO, const CodeGenOptions &CGO, |
| llvm::LLVMContext &C, |
| CoverageSourceInfo *CoverageInfo = nullptr) |
| : Diags(diags), Ctx(nullptr), HeaderSearchOpts(HSO), |
| PreprocessorOpts(PPO), CodeGenOpts(CGO), HandlingTopLevelDecls(0), |
| CoverageInfo(CoverageInfo), |
| M(new llvm::Module(ExpandModuleName(ModuleName, CGO), C)) { |
| C.setDiscardValueNames(CGO.DiscardValueNames); |
| } |
| |
| ~CodeGeneratorImpl() override { |
| // There should normally not be any leftover inline method definitions. |
| assert(DeferredInlineMemberFuncDefs.empty() || |
| Diags.hasErrorOccurred()); |
| } |
| |
| CodeGenModule &CGM() { |
| return *Builder; |
| } |
| |
| llvm::Module *GetModule() { |
| return M.get(); |
| } |
| |
| CGDebugInfo *getCGDebugInfo() { |
| return Builder->getModuleDebugInfo(); |
| } |
| |
| llvm::Module *ReleaseModule() { |
| return M.release(); |
| } |
| |
| const Decl *GetDeclForMangledName(StringRef MangledName) { |
| GlobalDecl Result; |
| if (!Builder->lookupRepresentativeDecl(MangledName, Result)) |
| return nullptr; |
| const Decl *D = Result.getCanonicalDecl().getDecl(); |
| if (auto FD = dyn_cast<FunctionDecl>(D)) { |
| if (FD->hasBody(FD)) |
| return FD; |
| } else if (auto TD = dyn_cast<TagDecl>(D)) { |
| if (auto Def = TD->getDefinition()) |
| return Def; |
| } |
| return D; |
| } |
| |
| llvm::Constant *GetAddrOfGlobal(GlobalDecl global, bool isForDefinition) { |
| return Builder->GetAddrOfGlobal(global, ForDefinition_t(isForDefinition)); |
| } |
| |
| llvm::Module *StartModule(llvm::StringRef ModuleName, |
| llvm::LLVMContext &C) { |
| assert(!M && "Replacing existing Module?"); |
| M.reset(new llvm::Module(ExpandModuleName(ModuleName, CodeGenOpts), C)); |
| Initialize(*Ctx); |
| return M.get(); |
| } |
| |
| void Initialize(ASTContext &Context) override { |
| Ctx = &Context; |
| |
| M->setTargetTriple(Ctx->getTargetInfo().getTriple().getTriple()); |
| M->setDataLayout(Ctx->getTargetInfo().getDataLayout()); |
| const auto &SDKVersion = Ctx->getTargetInfo().getSDKVersion(); |
| if (!SDKVersion.empty()) |
| M->setSDKVersion(SDKVersion); |
| Builder.reset(new CodeGen::CodeGenModule(Context, HeaderSearchOpts, |
| PreprocessorOpts, CodeGenOpts, |
| *M, Diags, CoverageInfo)); |
| |
| for (auto &&Lib : CodeGenOpts.DependentLibraries) |
| Builder->AddDependentLib(Lib); |
| for (auto &&Opt : CodeGenOpts.LinkerOptions) |
| Builder->AppendLinkerOptions(Opt); |
| } |
| |
| void HandleCXXStaticMemberVarInstantiation(VarDecl *VD) override { |
| if (Diags.hasErrorOccurred()) |
| return; |
| |
| Builder->HandleCXXStaticMemberVarInstantiation(VD); |
| } |
| |
| bool HandleTopLevelDecl(DeclGroupRef DG) override { |
| if (Diags.hasErrorOccurred()) |
| return true; |
| |
| HandlingTopLevelDeclRAII HandlingDecl(*this); |
| |
| // Make sure to emit all elements of a Decl. |
| for (DeclGroupRef::iterator I = DG.begin(), E = DG.end(); I != E; ++I) |
| Builder->EmitTopLevelDecl(*I); |
| |
| return true; |
| } |
| |
| void EmitDeferredDecls() { |
| if (DeferredInlineMemberFuncDefs.empty()) |
| return; |
| |
| // Emit any deferred inline method definitions. Note that more deferred |
| // methods may be added during this loop, since ASTConsumer callbacks |
| // can be invoked if AST inspection results in declarations being added. |
| HandlingTopLevelDeclRAII HandlingDecl(*this); |
| for (unsigned I = 0; I != DeferredInlineMemberFuncDefs.size(); ++I) |
| Builder->EmitTopLevelDecl(DeferredInlineMemberFuncDefs[I]); |
| DeferredInlineMemberFuncDefs.clear(); |
| } |
| |
| void HandleInlineFunctionDefinition(FunctionDecl *D) override { |
| if (Diags.hasErrorOccurred()) |
| return; |
| |
| assert(D->doesThisDeclarationHaveABody()); |
| |
| // We may want to emit this definition. However, that decision might be |
| // based on computing the linkage, and we have to defer that in case we |
| // are inside of something that will change the method's final linkage, |
| // e.g. |
| // typedef struct { |
| // void bar(); |
| // void foo() { bar(); } |
| // } A; |
| DeferredInlineMemberFuncDefs.push_back(D); |
| |
| // Provide some coverage mapping even for methods that aren't emitted. |
| // Don't do this for templated classes though, as they may not be |
| // instantiable. |
| if (!D->getLexicalDeclContext()->isDependentContext()) |
| Builder->AddDeferredUnusedCoverageMapping(D); |
| } |
| |
| /// HandleTagDeclDefinition - This callback is invoked each time a TagDecl |
| /// to (e.g. struct, union, enum, class) is completed. This allows the |
| /// client hack on the type, which can occur at any point in the file |
| /// (because these can be defined in declspecs). |
| void HandleTagDeclDefinition(TagDecl *D) override { |
| if (Diags.hasErrorOccurred()) |
| return; |
| |
| // Don't allow re-entrant calls to CodeGen triggered by PCH |
| // deserialization to emit deferred decls. |
| HandlingTopLevelDeclRAII HandlingDecl(*this, /*EmitDeferred=*/false); |
| |
| Builder->UpdateCompletedType(D); |
| |
| // For MSVC compatibility, treat declarations of static data members with |
| // inline initializers as definitions. |
| if (Ctx->getTargetInfo().getCXXABI().isMicrosoft()) { |
| for (Decl *Member : D->decls()) { |
| if (VarDecl *VD = dyn_cast<VarDecl>(Member)) { |
| if (Ctx->isMSStaticDataMemberInlineDefinition(VD) && |
| Ctx->DeclMustBeEmitted(VD)) { |
| Builder->EmitGlobal(VD); |
| } |
| } |
| } |
| } |
| // For OpenMP emit declare reduction functions, if required. |
| if (Ctx->getLangOpts().OpenMP) { |
| for (Decl *Member : D->decls()) { |
| if (auto *DRD = dyn_cast<OMPDeclareReductionDecl>(Member)) { |
| if (Ctx->DeclMustBeEmitted(DRD)) |
| Builder->EmitGlobal(DRD); |
| } else if (auto *DMD = dyn_cast<OMPDeclareMapperDecl>(Member)) { |
| if (Ctx->DeclMustBeEmitted(DMD)) |
| Builder->EmitGlobal(DMD); |
| } |
| } |
| } |
| } |
| |
| void HandleTagDeclRequiredDefinition(const TagDecl *D) override { |
| if (Diags.hasErrorOccurred()) |
| return; |
| |
| // Don't allow re-entrant calls to CodeGen triggered by PCH |
| // deserialization to emit deferred decls. |
| HandlingTopLevelDeclRAII HandlingDecl(*this, /*EmitDeferred=*/false); |
| |
| if (CodeGen::CGDebugInfo *DI = Builder->getModuleDebugInfo()) |
| if (const RecordDecl *RD = dyn_cast<RecordDecl>(D)) |
| DI->completeRequiredType(RD); |
| } |
| |
| void HandleTranslationUnit(ASTContext &Ctx) override { |
| // Release the Builder when there is no error. |
| if (!Diags.hasErrorOccurred() && Builder) |
| Builder->Release(); |
| |
| // If there are errors before or when releasing the Builder, reset |
| // the module to stop here before invoking the backend. |
| if (Diags.hasErrorOccurred()) { |
| if (Builder) |
| Builder->clear(); |
| M.reset(); |
| return; |
| } |
| } |
| |
| void AssignInheritanceModel(CXXRecordDecl *RD) override { |
| if (Diags.hasErrorOccurred()) |
| return; |
| |
| Builder->RefreshTypeCacheForClass(RD); |
| } |
| |
| void CompleteTentativeDefinition(VarDecl *D) override { |
| if (Diags.hasErrorOccurred()) |
| return; |
| |
| Builder->EmitTentativeDefinition(D); |
| } |
| |
| void CompleteExternalDeclaration(VarDecl *D) override { |
| Builder->EmitExternalDeclaration(D); |
| } |
| |
| void HandleVTable(CXXRecordDecl *RD) override { |
| if (Diags.hasErrorOccurred()) |
| return; |
| |
| Builder->EmitVTable(RD); |
| } |
| }; |
| } |
| |
| void CodeGenerator::anchor() { } |
| |
| CodeGenModule &CodeGenerator::CGM() { |
| return static_cast<CodeGeneratorImpl*>(this)->CGM(); |
| } |
| |
| llvm::Module *CodeGenerator::GetModule() { |
| return static_cast<CodeGeneratorImpl*>(this)->GetModule(); |
| } |
| |
| llvm::Module *CodeGenerator::ReleaseModule() { |
| return static_cast<CodeGeneratorImpl*>(this)->ReleaseModule(); |
| } |
| |
| CGDebugInfo *CodeGenerator::getCGDebugInfo() { |
| return static_cast<CodeGeneratorImpl*>(this)->getCGDebugInfo(); |
| } |
| |
| const Decl *CodeGenerator::GetDeclForMangledName(llvm::StringRef name) { |
| return static_cast<CodeGeneratorImpl*>(this)->GetDeclForMangledName(name); |
| } |
| |
| llvm::Constant *CodeGenerator::GetAddrOfGlobal(GlobalDecl global, |
| bool isForDefinition) { |
| return static_cast<CodeGeneratorImpl*>(this) |
| ->GetAddrOfGlobal(global, isForDefinition); |
| } |
| |
| llvm::Module *CodeGenerator::StartModule(llvm::StringRef ModuleName, |
| llvm::LLVMContext &C) { |
| return static_cast<CodeGeneratorImpl*>(this)->StartModule(ModuleName, C); |
| } |
| |
| CodeGenerator *clang::CreateLLVMCodeGen( |
| DiagnosticsEngine &Diags, llvm::StringRef ModuleName, |
| const HeaderSearchOptions &HeaderSearchOpts, |
| const PreprocessorOptions &PreprocessorOpts, const CodeGenOptions &CGO, |
| llvm::LLVMContext &C, CoverageSourceInfo *CoverageInfo) { |
| return new CodeGeneratorImpl(Diags, ModuleName, HeaderSearchOpts, |
| PreprocessorOpts, CGO, C, CoverageInfo); |
| } |