[DWARFLinker][NFC] Decrease DWARFLinker dependence on DwarfStreamer.

llvm/include/llvm/DWARFLinker/Classic/DWARFLinker.h

@@ -42,7 +42,8 @@ class DwarfEmitter {
   virtual ~DwarfEmitter() = default;
 
   /// Emit section named SecName with data SecData.
-  virtual void emitSectionContents(StringRef SecData, StringRef SecName) = 0;
+  virtual void emitSectionContents(StringRef SecData,
+                                   DebugSectionKind SecKind) = 0;
 
   /// Emit the abbreviation table \p Abbrevs to the .debug_abbrev section.
   virtual void
@@ -188,17 +189,6 @@ class DwarfEmitter {
 
   /// Dump the file to the disk.
   virtual void finish() = 0;
-
-  /// Emit the swift_ast section stored in \p Buffer.
-  virtual void emitSwiftAST(StringRef Buffer) = 0;
-
-  /// Emit the swift reflection section stored in \p Buffer.
-  virtual void emitSwiftReflectionSection(
-      llvm::binaryformat::Swift5ReflectionSectionKind ReflSectionKind,
-      StringRef Buffer, uint32_t Alignment, uint32_t Size) = 0;
-
-  /// Returns underlying AsmPrinter.
-  virtual AsmPrinter &getAsmPrinter() const = 0;
 };
 
 class DwarfStreamer;
@@ -232,10 +222,10 @@ class DWARFLinker : public DWARFLinkerBase {
                                          StringsTranslator);
   }
 
-  Error createEmitter(const Triple &TheTriple, OutputFileType FileType,
-                      raw_pwrite_stream &OutFile);
-
-  DwarfEmitter *getEmitter();
+  /// Set output DWARF emitter.
+  void setOutputDWARFEmitter(DwarfEmitter *Emitter) {
+    TheDwarfEmitter = Emitter;
+  }
 
   /// Add object file to be linked. Pre-load compile unit die. Call
   /// \p OnCUDieLoaded for each compile unit die. If specified \p File
@@ -762,7 +752,7 @@ class DWARFLinker : public DWARFLinkerBase {
   BumpPtrAllocator DIEAlloc;
   /// @}
 
-  std::unique_ptr<DwarfStreamer> TheDwarfEmitter;
+  DwarfEmitter *TheDwarfEmitter = nullptr;
   std::vector<LinkContext> ObjectContexts;
 
   /// The CIEs that have been emitted in the output section. The actual CIE

llvm/include/llvm/DWARFLinker/Classic/DWARFStreamer.h

@@ -45,18 +45,23 @@ class DwarfStreamer : public DwarfEmitter {
 public:
   DwarfStreamer(DWARFLinkerBase::OutputFileType OutFileType,
                 raw_pwrite_stream &OutFile,
-                std::function<StringRef(StringRef Input)> Translator,
+                DWARFLinkerBase::TranslatorFuncTy Translator,
                 DWARFLinkerBase::MessageHandlerTy Warning)
       : OutFile(OutFile), OutFileType(OutFileType), Translator(Translator),
         WarningHandler(Warning) {}
   virtual ~DwarfStreamer() = default;
 
+  static Expected<std::unique_ptr<DwarfStreamer>> createStreamer(
+      const Triple &TheTriple, DWARFLinkerBase::OutputFileType FileType,
+      raw_pwrite_stream &OutFile, DWARFLinkerBase::TranslatorFuncTy Translator,
+      DWARFLinkerBase::MessageHandlerTy Warning);
+
   Error init(Triple TheTriple, StringRef Swift5ReflectionSegmentName);
 
   /// Dump the file to the disk.
   void finish() override;
 
-  AsmPrinter &getAsmPrinter() const override { return *Asm; }
+  AsmPrinter &getAsmPrinter() const { return *Asm; }
 
   /// Set the current output section to debug_info and change
   /// the MC Dwarf version to \p DwarfVersion.
@@ -77,7 +82,8 @@ class DwarfStreamer : public DwarfEmitter {
                    unsigned DwarfVersion) override;
 
   /// Emit contents of section SecName From Obj.
-  void emitSectionContents(StringRef SecData, StringRef SecName) override;
+  void emitSectionContents(StringRef SecData,
+                           DebugSectionKind SecKind) override;
 
   /// Emit the string table described by \p Pool into .debug_str table.
   void emitStrings(const NonRelocatableStringpool &Pool) override;
@@ -91,12 +97,12 @@ class DwarfStreamer : public DwarfEmitter {
   void emitLineStrings(const NonRelocatableStringpool &Pool) override;
 
   /// Emit the swift_ast section stored in \p Buffer.
-  void emitSwiftAST(StringRef Buffer) override;
+  void emitSwiftAST(StringRef Buffer);
 
   /// Emit the swift reflection section stored in \p Buffer.
   void emitSwiftReflectionSection(
       llvm::binaryformat::Swift5ReflectionSectionKind ReflSectionKind,
-      StringRef Buffer, uint32_t Alignment, uint32_t Size) override;
+      StringRef Buffer, uint32_t Alignment, uint32_t Size);
 
   /// Emit debug ranges(.debug_ranges, .debug_rnglists) header.
   MCSymbol *emitDwarfDebugRangeListHeader(const CompileUnit &Unit) override;
@@ -215,6 +221,8 @@ class DwarfStreamer : public DwarfEmitter {
       WarningHandler(Warning, Context, nullptr);
   }
 
+  MCSection *getMCSection(DebugSectionKind SecKind);
+
   void emitMacroTableImpl(const DWARFDebugMacro *MacroTable,
                           const Offset2UnitMap &UnitMacroMap,
                           OffsetsStringPool &StringPool, uint64_t &OutOffset);

llvm/include/llvm/DWARFLinker/DWARFLinkerBase.h

@@ -23,6 +23,53 @@ class DWARFUnit;
 
 namespace dwarf_linker {
 
+/// List of tracked debug tables.
+enum class DebugSectionKind : uint8_t {
+  DebugInfo = 0,
+  DebugLine,
+  DebugFrame,
+  DebugRange,
+  DebugRngLists,
+  DebugLoc,
+  DebugLocLists,
+  DebugARanges,
+  DebugAbbrev,
+  DebugMacinfo,
+  DebugMacro,
+  DebugAddr,
+  DebugStr,
+  DebugLineStr,
+  DebugStrOffsets,
+  DebugPubNames,
+  DebugPubTypes,
+  DebugNames,
+  AppleNames,
+  AppleNamespaces,
+  AppleObjC,
+  AppleTypes,
+  NumberOfEnumEntries // must be last
+};
+
+static constexpr size_t SectionKindsNum =
+    static_cast<size_t>(DebugSectionKind::NumberOfEnumEntries);
+
+static constexpr StringLiteral SectionNames[SectionKindsNum] = {
+    "debug_info",     "debug_line",     "debug_frame",       "debug_ranges",
+    "debug_rnglists", "debug_loc",      "debug_loclists",    "debug_aranges",
+    "debug_abbrev",   "debug_macinfo",  "debug_macro",       "debug_addr",
+    "debug_str",      "debug_line_str", "debug_str_offsets", "debug_pubnames",
+    "debug_pubtypes", "debug_names",    "apple_names",       "apple_namespac",
+    "apple_objc",     "apple_types"};
+
+/// Return the name of the section.
+static constexpr const StringLiteral &
+getSectionName(DebugSectionKind SectionKind) {
+  return SectionNames[static_cast<uint8_t>(SectionKind)];
+}
+
+/// Recognise the table name and match it with the DebugSectionKind.
+std::optional<DebugSectionKind> parseDebugTableName(StringRef Name);
+
 /// The base interface for DWARFLinker implementations.
 class DWARFLinkerBase {
 public:

llvm/include/llvm/DWARFLinker/Parallel/DWARFLinker.h

@@ -89,30 +89,34 @@ namespace llvm {
 namespace dwarf_linker {
 namespace parallel {
 
-/// ExtraDwarfEmitter allows adding extra data to the DWARFLinker output.
-/// The finish() method should be called after all extra data are emitted.
-class ExtraDwarfEmitter {
-public:
-  virtual ~ExtraDwarfEmitter() = default;
-
-  /// Dump the file to the disk.
-  virtual void finish() = 0;
-
-  /// Emit section named SecName with data SecData.
-  virtual void emitSectionContents(StringRef SecData, StringRef SecName) = 0;
-
-  /// Emit the swift_ast section stored in \p Buffer.
-  virtual void emitSwiftAST(StringRef Buffer) = 0;
-
-  /// Emit the swift reflection section stored in \p Buffer.
-  virtual void emitSwiftReflectionSection(
-      llvm::binaryformat::Swift5ReflectionSectionKind ReflSectionKind,
-      StringRef Buffer, uint32_t Alignment, uint32_t Size) = 0;
-
-  /// Returns underlying AsmPrinter.
-  virtual AsmPrinter &getAsmPrinter() const = 0;
+/// This structure keeps data of the concrete section.
+struct SectionDescriptorBase {
+  SectionDescriptorBase(DebugSectionKind SectionKind, dwarf::FormParams Format,
+                        llvm::endianness Endianess)
+      : SectionKind(SectionKind), Format(Format), Endianess(Endianess) {}
+  virtual ~SectionDescriptorBase() = default;
+  /// Returns section content.
+  virtual StringRef getContents() = 0;
+  /// Returns section kind.
+  DebugSectionKind getKind() { return SectionKind; }
+  /// Returns section name.
+  const StringLiteral &getName() const { return getSectionName(SectionKind); }
+  /// Returns endianess used by section.
+  llvm::endianness getEndianess() const { return Endianess; }
+  /// Returns FormParams used by section.
+  dwarf::FormParams getFormParams() const { return Format; }
+
+protected:
+  /// The section kind.
+  DebugSectionKind SectionKind = DebugSectionKind::NumberOfEnumEntries;
+  /// Output format.
+  dwarf::FormParams Format = {4, 4, dwarf::DWARF32};
+  llvm::endianness Endianess = llvm::endianness::little;
 };
 
+using SectionHandlerTy =
+    std::function<void(std::shared_ptr<SectionDescriptorBase> Section)>;
+
 class DWARFLinker : public DWARFLinkerBase {
 public:
   virtual ~DWARFLinker() = default;
@@ -122,12 +126,11 @@ class DWARFLinker : public DWARFLinkerBase {
   createLinker(MessageHandlerTy ErrorHandler, MessageHandlerTy WarningHandler,
                TranslatorFuncTy StringsTranslator = nullptr);
 
-  /// Creates emitter for output dwarf.
-  virtual Error createEmitter(const Triple &TheTriple, OutputFileType FileType,
-                              raw_pwrite_stream &OutFile) = 0;
-
-  /// Returns previously created dwarf emitter. May be nullptr.
-  virtual ExtraDwarfEmitter *getEmitter() = 0;
+  /// Set output DWARF handler. Result of linking DWARF is set of sections
+  /// containing final debug info. DWARFLinkerBase::link() pass generated
+  /// sections using specified \p SectionHandler.
+  virtual void setOutputDWARFHandler(const Triple &TargetTriple,
+                                     SectionHandlerTy SectionHandler) = 0;
 };
 
 } // end of namespace parallel

llvm/lib/DWARFLinker/CMakeLists.txt

@@ -1,4 +1,5 @@
 add_llvm_component_library(LLVMDWARFLinker
+  DWARFLinkerBase.cpp
   Utils.cpp
 
   ADDITIONAL_HEADER_DIRS

llvm/lib/DWARFLinker/Classic/DWARFLinker.cpp

@@ -2644,19 +2644,22 @@ uint64_t DWARFLinker::DIECloner::cloneAllCompileUnits(
 
 void DWARFLinker::copyInvariantDebugSection(DWARFContext &Dwarf) {
   TheDwarfEmitter->emitSectionContents(Dwarf.getDWARFObj().getLocSection().Data,
-                                       "debug_loc");
+                                       DebugSectionKind::DebugLoc);
   TheDwarfEmitter->emitSectionContents(
-      Dwarf.getDWARFObj().getRangesSection().Data, "debug_ranges");
+      Dwarf.getDWARFObj().getRangesSection().Data,
+      DebugSectionKind::DebugRange);
   TheDwarfEmitter->emitSectionContents(
-      Dwarf.getDWARFObj().getFrameSection().Data, "debug_frame");
+      Dwarf.getDWARFObj().getFrameSection().Data, DebugSectionKind::DebugFrame);
   TheDwarfEmitter->emitSectionContents(Dwarf.getDWARFObj().getArangesSection(),
-                                       "debug_aranges");
+                                       DebugSectionKind::DebugARanges);
   TheDwarfEmitter->emitSectionContents(
-      Dwarf.getDWARFObj().getAddrSection().Data, "debug_addr");
+      Dwarf.getDWARFObj().getAddrSection().Data, DebugSectionKind::DebugAddr);
   TheDwarfEmitter->emitSectionContents(
-      Dwarf.getDWARFObj().getRnglistsSection().Data, "debug_rnglists");
+      Dwarf.getDWARFObj().getRnglistsSection().Data,
+      DebugSectionKind::DebugRngLists);
   TheDwarfEmitter->emitSectionContents(
-      Dwarf.getDWARFObj().getLoclistsSection().Data, "debug_loclists");
+      Dwarf.getDWARFObj().getLoclistsSection().Data,
+      DebugSectionKind::DebugLocLists);
 }
 
 void DWARFLinker::addObjectFile(DWARFFile &File, ObjFileLoaderTy Loader,
@@ -2848,7 +2851,7 @@ Error DWARFLinker::link() {
       SizeByObject[OptContext.File.FileName].Input =
           getDebugInfoSize(*OptContext.File.Dwarf);
       SizeByObject[OptContext.File.FileName].Output =
-          DIECloner(*this, TheDwarfEmitter.get(), OptContext.File, DIEAlloc,
+          DIECloner(*this, TheDwarfEmitter, OptContext.File, DIEAlloc,
                     OptContext.CompileUnits, Options.Update, DebugStrPool,
                     DebugLineStrPool, StringOffsetPool)
               .cloneAllCompileUnits(*OptContext.File.Dwarf, OptContext.File,
@@ -3011,7 +3014,7 @@ Error DWARFLinker::cloneModuleUnit(LinkContext &Context, RefModuleUnit &Unit,
   UnitListTy CompileUnits;
   CompileUnits.emplace_back(std::move(Unit.Unit));
   assert(TheDwarfEmitter);
-  DIECloner(*this, TheDwarfEmitter.get(), Unit.File, DIEAlloc, CompileUnits,
+  DIECloner(*this, TheDwarfEmitter, Unit.File, DIEAlloc, CompileUnits,
             Options.Update, DebugStrPool, DebugLineStrPool, StringOffsetPool)
       .cloneAllCompileUnits(*Unit.File.Dwarf, Unit.File,
                             Unit.File.Dwarf->isLittleEndian());
@@ -3030,16 +3033,4 @@ void DWARFLinker::verifyInput(const DWARFFile &File) {
   }
 }
 
-Error DWARFLinker::createEmitter(const Triple &TheTriple,
-                                 OutputFileType FileType,
-                                 raw_pwrite_stream &OutFile) {
-
-  TheDwarfEmitter = std::make_unique<DwarfStreamer>(
-      FileType, OutFile, StringsTranslator, WarningHandler);
-
-  return TheDwarfEmitter->init(TheTriple, "__DWARF");
-}
-
-DwarfEmitter *DWARFLinker::getEmitter() { return TheDwarfEmitter.get(); }
-
 } // namespace llvm