1 //===--- ModuleBuilder.cpp - Emit LLVM Code from ASTs ---------------------===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This builds an AST and converts it to LLVM Code.
12 //===----------------------------------------------------------------------===//
14 #include "clang/CodeGen/ModuleBuilder.h"
15 #include "CGDebugInfo.h"
16 #include "CodeGenModule.h"
17 #include "clang/AST/ASTContext.h"
18 #include "clang/AST/DeclObjC.h"
19 #include "clang/AST/Expr.h"
20 #include "clang/Basic/Diagnostic.h"
21 #include "clang/Basic/TargetInfo.h"
22 #include "clang/Frontend/CodeGenOptions.h"
23 #include "llvm/ADT/StringRef.h"
24 #include "llvm/IR/DataLayout.h"
25 #include "llvm/IR/LLVMContext.h"
26 #include "llvm/IR/Module.h"
28 using namespace clang;
31 class CodeGeneratorImpl : public CodeGenerator {
32 DiagnosticsEngine &Diags;
33 std::unique_ptr<const llvm::DataLayout> TD;
35 const CodeGenOptions CodeGenOpts; // Intentionally copied in.
37 unsigned HandlingTopLevelDecls;
38 struct HandlingTopLevelDeclRAII {
39 CodeGeneratorImpl &Self;
40 HandlingTopLevelDeclRAII(CodeGeneratorImpl &Self) : Self(Self) {
41 ++Self.HandlingTopLevelDecls;
43 ~HandlingTopLevelDeclRAII() {
44 if (--Self.HandlingTopLevelDecls == 0)
45 Self.EmitDeferredDecls();
49 CoverageSourceInfo *CoverageInfo;
52 std::unique_ptr<llvm::Module> M;
53 std::unique_ptr<CodeGen::CodeGenModule> Builder;
56 SmallVector<CXXMethodDecl *, 8> DeferredInlineMethodDefinitions;
59 CodeGeneratorImpl(DiagnosticsEngine &diags, const std::string& ModuleName,
60 const CodeGenOptions &CGO, llvm::LLVMContext& C,
61 CoverageSourceInfo *CoverageInfo = nullptr)
62 : Diags(diags), Ctx(nullptr), CodeGenOpts(CGO), HandlingTopLevelDecls(0),
63 CoverageInfo(CoverageInfo),
64 M(new llvm::Module(ModuleName, C)) {}
66 ~CodeGeneratorImpl() override {
67 // There should normally not be any leftover inline method definitions.
68 assert(DeferredInlineMethodDefinitions.empty() ||
69 Diags.hasErrorOccurred());
72 llvm::Module* GetModule() override {
76 const Decl *GetDeclForMangledName(StringRef MangledName) override {
78 if (!Builder->lookupRepresentativeDecl(MangledName, Result))
80 const Decl *D = Result.getCanonicalDecl().getDecl();
81 if (auto FD = dyn_cast<FunctionDecl>(D)) {
84 } else if (auto TD = dyn_cast<TagDecl>(D)) {
85 if (auto Def = TD->getDefinition())
91 llvm::Module *ReleaseModule() override { return M.release(); }
93 void Initialize(ASTContext &Context) override {
96 M->setTargetTriple(Ctx->getTargetInfo().getTriple().getTriple());
97 M->setDataLayout(Ctx->getTargetInfo().getTargetDescription());
99 new llvm::DataLayout(Ctx->getTargetInfo().getTargetDescription()));
100 Builder.reset(new CodeGen::CodeGenModule(Context, CodeGenOpts, *M, *TD,
101 Diags, CoverageInfo));
103 for (size_t i = 0, e = CodeGenOpts.DependentLibraries.size(); i < e; ++i)
104 HandleDependentLibrary(CodeGenOpts.DependentLibraries[i]);
107 void HandleCXXStaticMemberVarInstantiation(VarDecl *VD) override {
108 if (Diags.hasErrorOccurred())
111 Builder->HandleCXXStaticMemberVarInstantiation(VD);
114 bool HandleTopLevelDecl(DeclGroupRef DG) override {
115 if (Diags.hasErrorOccurred())
118 HandlingTopLevelDeclRAII HandlingDecl(*this);
120 // Make sure to emit all elements of a Decl.
121 for (DeclGroupRef::iterator I = DG.begin(), E = DG.end(); I != E; ++I)
122 Builder->EmitTopLevelDecl(*I);
127 void EmitDeferredDecls() {
128 if (DeferredInlineMethodDefinitions.empty())
131 // Emit any deferred inline method definitions. Note that more deferred
132 // methods may be added during this loop, since ASTConsumer callbacks
133 // can be invoked if AST inspection results in declarations being added.
134 HandlingTopLevelDeclRAII HandlingDecl(*this);
135 for (unsigned I = 0; I != DeferredInlineMethodDefinitions.size(); ++I)
136 Builder->EmitTopLevelDecl(DeferredInlineMethodDefinitions[I]);
137 DeferredInlineMethodDefinitions.clear();
140 void HandleInlineMethodDefinition(CXXMethodDecl *D) override {
141 if (Diags.hasErrorOccurred())
144 assert(D->doesThisDeclarationHaveABody());
146 // We may want to emit this definition. However, that decision might be
147 // based on computing the linkage, and we have to defer that in case we
148 // are inside of something that will change the method's final linkage,
152 // void foo() { bar(); }
154 DeferredInlineMethodDefinitions.push_back(D);
156 // Provide some coverage mapping even for methods that aren't emitted.
157 // Don't do this for templated classes though, as they may not be
159 if (!D->getParent()->getDescribedClassTemplate())
160 Builder->AddDeferredUnusedCoverageMapping(D);
163 /// HandleTagDeclDefinition - This callback is invoked each time a TagDecl
164 /// to (e.g. struct, union, enum, class) is completed. This allows the
165 /// client hack on the type, which can occur at any point in the file
166 /// (because these can be defined in declspecs).
167 void HandleTagDeclDefinition(TagDecl *D) override {
168 if (Diags.hasErrorOccurred())
171 Builder->UpdateCompletedType(D);
173 // For MSVC compatibility, treat declarations of static data members with
174 // inline initializers as definitions.
175 if (Ctx->getLangOpts().MSVCCompat) {
176 for (Decl *Member : D->decls()) {
177 if (VarDecl *VD = dyn_cast<VarDecl>(Member)) {
178 if (Ctx->isMSStaticDataMemberInlineDefinition(VD) &&
179 Ctx->DeclMustBeEmitted(VD)) {
180 Builder->EmitGlobal(VD);
187 void HandleTagDeclRequiredDefinition(const TagDecl *D) override {
188 if (Diags.hasErrorOccurred())
191 if (CodeGen::CGDebugInfo *DI = Builder->getModuleDebugInfo())
192 if (const RecordDecl *RD = dyn_cast<RecordDecl>(D))
193 DI->completeRequiredType(RD);
196 void HandleTranslationUnit(ASTContext &Ctx) override {
197 if (Diags.hasErrorOccurred()) {
208 void CompleteTentativeDefinition(VarDecl *D) override {
209 if (Diags.hasErrorOccurred())
212 Builder->EmitTentativeDefinition(D);
215 void HandleVTable(CXXRecordDecl *RD) override {
216 if (Diags.hasErrorOccurred())
219 Builder->EmitVTable(RD);
222 void HandleLinkerOptionPragma(llvm::StringRef Opts) override {
223 Builder->AppendLinkerOptions(Opts);
226 void HandleDetectMismatch(llvm::StringRef Name,
227 llvm::StringRef Value) override {
228 Builder->AddDetectMismatch(Name, Value);
231 void HandleDependentLibrary(llvm::StringRef Lib) override {
232 Builder->AddDependentLib(Lib);
237 void CodeGenerator::anchor() { }
239 CodeGenerator *clang::CreateLLVMCodeGen(DiagnosticsEngine &Diags,
240 const std::string& ModuleName,
241 const CodeGenOptions &CGO,
242 llvm::LLVMContext& C,
243 CoverageSourceInfo *CoverageInfo) {
244 return new CodeGeneratorImpl(Diags, ModuleName, CGO, C, CoverageInfo);