[Dsymutil][Debuginfo][NFC] #4 Refactor dsymutil to separate DWARF optimizing part.

Summary:
The primary goal of this refactoring is to separate DWARF optimizing part.
So that it could be reused by linker or by any other client.
There was a thread on llvm-dev discussing the necessity of such a refactoring:

http://lists.llvm.org/pipermail/llvm-dev/2019-September/135068.html.

This is a final part from series of patches for dsymutil.
Previous patches : D71068, D71839, D72476. This patch:

1. Creates lib/DWARFLinker interface :

   void addObjectFile(DwarfLinkerObjFile &ObjFile);
   bool link();
   void setOptions;

1. Moves all linking logic from tools/dsymutil/DwarfLinkerForBinary
   into lib/DWARFLinker.
2. Renames RelocationManager into AddressesManager.
3. Remarks creation logic moved from separate parallel execution
   into object file loading routine.

Testing: it passes "check-all" lit testing. MD5 checksum for clang .dSYM bundle
matches for the dsymutil with/without that patch.

Reviewers: JDevlieghere, friss, dblaikie, aprantl, jdoerfert

Reviewed By: JDevlieghere

Subscribers: merge_guards_bot, hiraditya, jfb, llvm-commits, probinson, thegameg

Tags: #llvm, #debug-info

Differential Revision: https://reviews.llvm.org/D72915

llvm/include/llvm/CodeGen/DIE.h

@@ -910,6 +910,9 @@ public:
   ///
   unsigned ComputeSize(const AsmPrinter *AP) const;
 
+  // TODO: move setSize() and Size to DIEValueList.
+  void setSize(unsigned size) { Size = size; }
+
   /// BestForm - Choose the best form for data.
   ///
   dwarf::Form BestForm(unsigned DwarfVersion) const {
@@ -944,6 +947,9 @@ public:
   ///
   unsigned ComputeSize(const AsmPrinter *AP) const;
 
+  // TODO: move setSize() and Size to DIEValueList.
+  void setSize(unsigned size) { Size = size; }
+
   /// BestForm - Choose the best form for data.
   ///
   dwarf::Form BestForm() const {

llvm/include/llvm/DWARFLinker/DWARFLinker.h

@@ -21,6 +21,13 @@ namespace llvm {
 
 enum class DwarfLinkerClient { Dsymutil, LLD, General };
 
+/// The kind of accelerator tables we should emit.
+enum class AccelTableKind {
+  Apple,   ///< .apple_names, .apple_namespaces, .apple_types, .apple_objc.
+  Dwarf,   ///< DWARF v5 .debug_names.
+  Default, ///< Dwarf for DWARF5 or later, Apple otherwise.
+};
+
 /// Partial address range. Besides an offset, only the
 /// HighPC is stored. The structure is stored in a map where the LowPC is the
 /// key.
@@ -193,6 +200,599 @@ public:
   virtual uint64_t getDebugInfoSectionSize() const = 0;
 };
 
+using UnitListTy = std::vector<std::unique_ptr<CompileUnit>>;
+
+/// this class represents Object File and it`s additional info.
+class DwarfLinkerObjFile {
+public:
+  DwarfLinkerObjFile(StringRef Name, const object::ObjectFile *File,
+                     const std::vector<std::string> &Warnings)
+      : FileName(Name), ObjFile(File), Warnings(Warnings) {}
+
+  /// object file name.
+  StringRef FileName;
+  /// object file.
+  const object::ObjectFile *ObjFile;
+  /// helpful address information(list of valid address ranges, relocations).
+  std::unique_ptr<AddressesMap> Addresses;
+  /// warnings for object file.
+  const std::vector<std::string> &Warnings;
+};
+
+typedef std::function<void(const Twine &Warning, StringRef Context,
+                           const DWARFDie *DIE)>
+    messageHandler;
+typedef std::function<ErrorOr<DwarfLinkerObjFile &>(StringRef ContainerName,
+                                                    StringRef Path)>
+    objFileLoader;
+typedef std::map<std::string, std::string> swiftInterfacesMap;
+
+/// The core of the Dwarf linking logic.
+///
+/// The generation of the dwarf information from the object files will be
+/// driven by the selection of 'root DIEs', which are DIEs that
+/// describe variables or functions that resolves to the corresponding
+/// code section(and thus have entries in the Addresses map). All the debug
+/// information that will be generated(the DIEs, but also the line
+/// tables, ranges, ...) is derived from that set of root DIEs.
+///
+/// The root DIEs are identified because they contain relocations that
+/// points to code section(the low_pc for a function, the location for
+/// a variable). These relocations are called ValidRelocs in the
+/// AddressesInfo and are gathered as a very first step when we start
+/// processing a object file.
+class DWARFLinker {
+public:
+  DWARFLinker(const Triple &Triple, DwarfEmitter *Emitter,
+              DwarfLinkerClient ClientID = DwarfLinkerClient::General)
+      : Triple(Triple), DwarfEmitter(Emitter), DwarfLinkerClientID(ClientID) {}
+
+  /// Add object file to be linked.
+  void addObjectFile(DwarfLinkerObjFile &ObjFile);
+
+  /// Link debug info for added objFiles. Object
+  /// files are linked all together.
+  bool link();
+
+  /// A number of methods setting various linking options:
+
+  /// Allows to generate log of linking process to the standard output.
+  void setVerbosity(bool Verbose) { Options.Verbose = Verbose; }
+
+  /// Do not emit linked dwarf info.
+  void setNoOutput(bool NoOut) { Options.NoOutput = NoOut; }
+
+  /// Do not unique types according to ODR.
+  void setNoODR(bool NoODR) { Options.NoODR = NoODR; }
+
+  /// update existing DWARF info(for the linked binary).
+  void setUpdate(bool Update) { Options.Update = Update; }
+
+  /// Use specified number of threads for parallel files linking.
+  void setNumThreads(unsigned NumThreads) { Options.Threads = NumThreads; }
+
+  /// Set kind of accelerator tables to be generated.
+  void setAccelTableKind(AccelTableKind Kind) {
+    Options.TheAccelTableKind = Kind;
+  }
+
+  /// Set prepend path for clang modules.
+  void setPrependPath(const std::string &Ppath) { Options.PrependPath = Ppath; }
+
+  /// Set translator which would be used for strings.
+  void
+  setStringsTranslator(std::function<StringRef(StringRef)> StringsTranslator) {
+    this->StringsTranslator = StringsTranslator;
+  }
+
+  /// Set estimated objects files amount, for preliminary data allocation.
+  void setEstimatedObjfilesAmount(unsigned ObjFilesNum) {
+    ObjectContexts.reserve(ObjFilesNum);
+  }
+
+  /// Set warning handler which would be used to report warnings.
+  void setWarningHandler(messageHandler Handler) {
+    Options.WarningHandler = Handler;
+  }
+
+  /// Set error handler which would be used to report errors.
+  void setErrorHandler(messageHandler Handler) {
+    Options.ErrorHandler = Handler;
+  }
+
+  /// Set object files loader which would be used to load
+  /// additional objects for splitted dwarf.
+  void setObjFileLoader(objFileLoader Loader) {
+    Options.ObjFileLoader = Loader;
+  }
+
+  /// Set map for Swift interfaces.
+  void setSwiftInterfacesMap(swiftInterfacesMap *Map) {
+    Options.ParseableSwiftInterfaces = Map;
+  }
+
+private:
+  /// Flags passed to DwarfLinker::lookForDIEsToKeep
+  enum TraversalFlags {
+    TF_Keep = 1 << 0,            ///< Mark the traversed DIEs as kept.
+    TF_InFunctionScope = 1 << 1, ///< Current scope is a function scope.
+    TF_DependencyWalk = 1 << 2,  ///< Walking the dependencies of a kept DIE.
+    TF_ParentWalk = 1 << 3,      ///< Walking up the parents of a kept DIE.
+    TF_ODR = 1 << 4,             ///< Use the ODR while keeping dependents.
+    TF_SkipPC = 1 << 5,          ///< Skip all location attributes.
+  };
+
+  /// The  distinct types of work performed by the work loop.
+  enum class WorklistItemType {
+    /// Given a DIE, look for DIEs to be kept.
+    LookForDIEsToKeep,
+    /// Given a DIE, look for children of this DIE to be kept.
+    LookForChildDIEsToKeep,
+    /// Given a DIE, look for DIEs referencing this DIE to be kept.
+    LookForRefDIEsToKeep,
+    /// Given a DIE, look for parent DIEs to be kept.
+    LookForParentDIEsToKeep,
+    /// Given a DIE, update its incompleteness based on whether its children are
+    /// incomplete.
+    UpdateChildIncompleteness,
+    /// Given a DIE, update its incompleteness based on whether the DIEs it
+    /// references are incomplete.
+    UpdateRefIncompleteness,
+  };
+
+  /// This class represents an item in the work list. The type defines what kind
+  /// of work needs to be performed when processing the current item. The flags
+  /// and info fields are optional based on the type.
+  struct WorklistItem {
+    WorklistItemType Type;
+    DWARFDie Die;
+    CompileUnit &CU;
+    unsigned Flags;
+    unsigned AncestorIdx = 0;
+    CompileUnit::DIEInfo *OtherInfo = nullptr;
+
+    WorklistItem(DWARFDie Die, CompileUnit &CU, unsigned Flags,
+                 WorklistItemType T = WorklistItemType::LookForDIEsToKeep)
+        : Type(T), Die(Die), CU(CU), Flags(Flags) {}
+
+    WorklistItem(DWARFDie Die, CompileUnit &CU, WorklistItemType T,
+                 CompileUnit::DIEInfo *OtherInfo = nullptr)
+        : Type(T), Die(Die), CU(CU), OtherInfo(OtherInfo) {}
+
+    WorklistItem(unsigned AncestorIdx, CompileUnit &CU, unsigned Flags)
+        : Type(WorklistItemType::LookForParentDIEsToKeep), CU(CU), Flags(Flags),
+          AncestorIdx(AncestorIdx) {}
+  };
+
+  /// returns true if we need to translate strings.
+  bool needToTranslateStrings() { return StringsTranslator != nullptr; }
+
+  void reportWarning(const Twine &Warning, const DwarfLinkerObjFile &OF,
+                     const DWARFDie *DIE = nullptr) const {
+    if (Options.WarningHandler != nullptr)
+      Options.WarningHandler(Warning, OF.FileName, DIE);
+  }
+
+  void reportError(const Twine &Warning, const DwarfLinkerObjFile &OF,
+                   const DWARFDie *DIE = nullptr) const {
+    if (Options.ErrorHandler != nullptr)
+      Options.ErrorHandler(Warning, OF.FileName, DIE);
+  }
+
+  /// Remembers the oldest and newest DWARF version we've seen in a unit.
+  void updateDwarfVersion(unsigned Version) {
+    MaxDwarfVersion = std::max(MaxDwarfVersion, Version);
+    MinDwarfVersion = std::min(MinDwarfVersion, Version);
+  }
+
+  /// Remembers the kinds of accelerator tables we've seen in a unit.
+  void updateAccelKind(DWARFContext &Dwarf);
+
+  /// Emit warnings as Dwarf compile units to leave a trail after linking.
+  bool emitPaperTrailWarnings(const DwarfLinkerObjFile &OF,
+                              OffsetsStringPool &StringPool);
+
+  void copyInvariantDebugSection(const object::ObjectFile &Obj);
+
+  /// Keeps track of data associated with one object during linking.
+  struct LinkContext {
+    DwarfLinkerObjFile &ObjectFile;
+    std::unique_ptr<DWARFContext> DwarfContext;
+    UnitListTy CompileUnits;
+    bool Skip = false;
+
+    LinkContext(DwarfLinkerObjFile &objFile) : ObjectFile(objFile) {
+
+      if (ObjectFile.ObjFile)
+        DwarfContext = DWARFContext::create(*ObjectFile.ObjFile);
+    }
+
+    /// Clear part of the context that's no longer needed when we're done with
+    /// the debug object.
+    void clear() {
+      DwarfContext.reset(nullptr);
+      CompileUnits.clear();
+      ObjectFile.Addresses->clear();
+    }
+  };
+
+  /// Called before emitting object data
+  void cleanupAuxiliarryData(LinkContext &Context);
+
+  /// Look at the parent of the given DIE and decide whether they should be
+  /// kept.
+  void lookForParentDIEsToKeep(unsigned AncestorIdx, CompileUnit &CU,
+                               unsigned Flags,
+                               SmallVectorImpl<WorklistItem> &Worklist);
+
+  /// Look at the children of the given DIE and decide whether they should be
+  /// kept.
+  void lookForChildDIEsToKeep(const DWARFDie &Die, CompileUnit &CU,
+                              unsigned Flags,
+                              SmallVectorImpl<WorklistItem> &Worklist);
+
+  /// Look at DIEs referenced by the given DIE and decide whether they should be
+  /// kept. All DIEs referenced though attributes should be kept.
+  void lookForRefDIEsToKeep(const DWARFDie &Die, CompileUnit &CU,
+                            unsigned Flags, const UnitListTy &Units,
+                            const DwarfLinkerObjFile &OF,
+                            SmallVectorImpl<WorklistItem> &Worklist);
+
+  /// \defgroup FindRootDIEs Find DIEs corresponding to Address map entries.
+  ///
+  /// @{
+  /// Recursively walk the \p DIE tree and look for DIEs to
+  /// keep. Store that information in \p CU's DIEInfo.
+  ///
+  /// The return value indicates whether the DIE is incomplete.
+  void lookForDIEsToKeep(AddressesMap &RelocMgr, RangesTy &Ranges,
+                         const UnitListTy &Units, const DWARFDie &DIE,
+                         const DwarfLinkerObjFile &OF, CompileUnit &CU,
+                         unsigned Flags);
+
+  /// If this compile unit is really a skeleton CU that points to a
+  /// clang module, register it in ClangModules and return true.
+  ///
+  /// A skeleton CU is a CU without children, a DW_AT_gnu_dwo_name
+  /// pointing to the module, and a DW_AT_gnu_dwo_id with the module
+  /// hash.
+  bool registerModuleReference(DWARFDie CUDie, const DWARFUnit &Unit,
+                               const DwarfLinkerObjFile &OF,
+                               OffsetsStringPool &OffsetsStringPool,
+                               UniquingStringPool &UniquingStringPoolStringPool,
+                               DeclContextTree &ODRContexts,
+                               uint64_t ModulesEndOffset, unsigned &UnitID,
+                               bool IsLittleEndian, unsigned Indent = 0,
+                               bool Quiet = false);
+
+  /// Recursively add the debug info in this clang module .pcm
+  /// file (and all the modules imported by it in a bottom-up fashion)
+  /// to Units.
+  Error loadClangModule(DWARFDie CUDie, StringRef FilePath,
+                        StringRef ModuleName, uint64_t DwoId,
+                        const DwarfLinkerObjFile &OF,
+                        OffsetsStringPool &OffsetsStringPool,
+                        UniquingStringPool &UniquingStringPool,
+                        DeclContextTree &ODRContexts, uint64_t ModulesEndOffset,
+                        unsigned &UnitID, bool IsLittleEndian,
+                        unsigned Indent = 0, bool Quiet = false);
+
+  /// Mark the passed DIE as well as all the ones it depends on as kept.
+  void keepDIEAndDependencies(AddressesMap &RelocMgr, RangesTy &Ranges,
+                              const UnitListTy &Units, const DWARFDie &DIE,
+                              CompileUnit::DIEInfo &MyInfo,
+                              const DwarfLinkerObjFile &OF, CompileUnit &CU,
+                              bool UseODR);
+
+  unsigned shouldKeepDIE(AddressesMap &RelocMgr, RangesTy &Ranges,
+                         const DWARFDie &DIE, const DwarfLinkerObjFile &OF,
+                         CompileUnit &Unit, CompileUnit::DIEInfo &MyInfo,
+                         unsigned Flags);
+
+  /// Check if a variable describing DIE should be kept.
+  /// \returns updated TraversalFlags.
+  unsigned shouldKeepVariableDIE(AddressesMap &RelocMgr, const DWARFDie &DIE,
+                                 CompileUnit &Unit,
+                                 CompileUnit::DIEInfo &MyInfo, unsigned Flags);
+
+  unsigned shouldKeepSubprogramDIE(AddressesMap &RelocMgr, RangesTy &Ranges,
+                                   const DWARFDie &DIE,
+                                   const DwarfLinkerObjFile &OF,
+                                   CompileUnit &Unit,
+                                   CompileUnit::DIEInfo &MyInfo,
+                                   unsigned Flags);
+
+  /// Resolve the DIE attribute reference that has been extracted in \p
+  /// RefValue. The resulting DIE might be in another CompileUnit which is
+  /// stored into \p ReferencedCU. \returns null if resolving fails for any
+  /// reason.
+  DWARFDie resolveDIEReference(const DwarfLinkerObjFile &OF,
+                               const UnitListTy &Units,
+                               const DWARFFormValue &RefValue,
+                               const DWARFDie &DIE, CompileUnit *&RefCU);
+
+  /// @}
+
+  /// \defgroup Methods used to link the debug information
+  ///
+  /// @{
+
+  struct DWARFLinkerOptions;
+
+  class DIECloner {
+    DWARFLinker &Linker;
+    DwarfEmitter *Emitter;
+    DwarfLinkerObjFile &ObjFile;
+
+    /// Allocator used for all the DIEValue objects.
+    BumpPtrAllocator &DIEAlloc;
+
+    std::vector<std::unique_ptr<CompileUnit>> &CompileUnits;
+
+    bool Update;
+
+  public:
+    DIECloner(DWARFLinker &Linker, DwarfEmitter *Emitter,
+              DwarfLinkerObjFile &ObjFile, BumpPtrAllocator &DIEAlloc,
+              std::vector<std::unique_ptr<CompileUnit>> &CompileUnits,
+              bool Update)
+        : Linker(Linker), Emitter(Emitter), ObjFile(ObjFile),
+          DIEAlloc(DIEAlloc), CompileUnits(CompileUnits), Update(Update) {}
+
+    /// Recursively clone \p InputDIE into an tree of DIE objects
+    /// where useless (as decided by lookForDIEsToKeep()) bits have been
+    /// stripped out and addresses have been rewritten according to the
+    /// address map.
+    ///
+    /// \param OutOffset is the offset the cloned DIE in the output
+    /// compile unit.
+    /// \param PCOffset (while cloning a function scope) is the offset
+    /// applied to the entry point of the function to get the linked address.
+    /// \param Die the output DIE to use, pass NULL to create one.
+    /// \returns the root of the cloned tree or null if nothing was selected.
+    DIE *cloneDIE(const DWARFDie &InputDIE, const DwarfLinkerObjFile &OF,
+                  CompileUnit &U, OffsetsStringPool &StringPool,
+                  int64_t PCOffset, uint32_t OutOffset, unsigned Flags,
+                  bool IsLittleEndian, DIE *Die = nullptr);
+
+    /// Construct the output DIE tree by cloning the DIEs we
+    /// chose to keep above. If there are no valid relocs, then there's
+    /// nothing to clone/emit.
+    void cloneAllCompileUnits(DWARFContext &DwarfContext,
+                              const DwarfLinkerObjFile &OF,
+                              OffsetsStringPool &StringPool,
+                              bool IsLittleEndian);
+
+  private:
+    using AttributeSpec = DWARFAbbreviationDeclaration::AttributeSpec;
+
+    /// Information gathered and exchanged between the various
+    /// clone*Attributes helpers about the attributes of a particular DIE.
+    struct AttributesInfo {
+      /// Names.
+      DwarfStringPoolEntryRef Name, MangledName, NameWithoutTemplate;
+
+      /// Offsets in the string pool.
+      uint32_t NameOffset = 0;
+      uint32_t MangledNameOffset = 0;
+
+      /// Value of AT_low_pc in the input DIE
+      uint64_t OrigLowPc = std::numeric_limits<uint64_t>::max();
+
+      /// Value of AT_high_pc in the input DIE
+      uint64_t OrigHighPc = 0;
+
+      /// Offset to apply to PC addresses inside a function.
+      int64_t PCOffset = 0;
+
+      /// Does the DIE have a low_pc attribute?
+      bool HasLowPc = false;
+
+      /// Does the DIE have a ranges attribute?
+      bool HasRanges = false;
+
+      /// Is this DIE only a declaration?
+      bool IsDeclaration = false;
+
+      AttributesInfo() = default;
+    };
+
+    friend DIECloner;
+
+    /// Helper for cloneDIE.
+    unsigned cloneAttribute(DIE &Die, const DWARFDie &InputDIE,
+                            const DwarfLinkerObjFile &OF, CompileUnit &U,
+                            OffsetsStringPool &StringPool,
+                            const DWARFFormValue &Val,
+                            const AttributeSpec AttrSpec, unsigned AttrSize,
+                            AttributesInfo &AttrInfo, bool IsLittleEndian);
+
+    /// Clone a string attribute described by \p AttrSpec and add
+    /// it to \p Die.
+    /// \returns the size of the new attribute.
+    unsigned cloneStringAttribute(DIE &Die, AttributeSpec AttrSpec,
+                                  const DWARFFormValue &Val, const DWARFUnit &U,
+                                  OffsetsStringPool &StringPool,
+                                  AttributesInfo &Info);
+
+    /// Clone an attribute referencing another DIE and add
+    /// it to \p Die.
+    /// \returns the size of the new attribute.
+    unsigned cloneDieReferenceAttribute(DIE &Die, const DWARFDie &InputDIE,
+                                        AttributeSpec AttrSpec,
+                                        unsigned AttrSize,
+                                        const DWARFFormValue &Val,
+                                        const DwarfLinkerObjFile &OF,
+                                        CompileUnit &Unit);
+
+    /// Clone a DWARF expression that may be referencing another DIE.
+    void cloneExpression(DataExtractor &Data, DWARFExpression Expression,
+                         const DwarfLinkerObjFile &OF, CompileUnit &Unit,
+                         SmallVectorImpl<uint8_t> &OutputBuffer);
+
+    /// Clone an attribute referencing another DIE and add
+    /// it to \p Die.
+    /// \returns the size of the new attribute.
+    unsigned cloneBlockAttribute(DIE &Die, const DwarfLinkerObjFile &OF,
+                                 CompileUnit &Unit, AttributeSpec AttrSpec,
+                                 const DWARFFormValue &Val, unsigned AttrSize,
+                                 bool IsLittleEndian);
+
+    /// Clone an attribute referencing another DIE and add
+    /// it to \p Die.
+    /// \returns the size of the new attribute.
+    unsigned cloneAddressAttribute(DIE &Die, AttributeSpec AttrSpec,
+                                   const DWARFFormValue &Val,
+                                   const CompileUnit &Unit,
+                                   AttributesInfo &Info);
+
+    /// Clone a scalar attribute  and add it to \p Die.
+    /// \returns the size of the new attribute.
+    unsigned cloneScalarAttribute(DIE &Die, const DWARFDie &InputDIE,
+                                  const DwarfLinkerObjFile &OF, CompileUnit &U,
+                                  AttributeSpec AttrSpec,
+                                  const DWARFFormValue &Val, unsigned AttrSize,
+                                  AttributesInfo &Info);
+
+    /// Get the potential name and mangled name for the entity
+    /// described by \p Die and store them in \Info if they are not
+    /// already there.
+    /// \returns is a name was found.
+    bool getDIENames(const DWARFDie &Die, AttributesInfo &Info,
+                     OffsetsStringPool &StringPool, bool StripTemplate = false);
+
+    /// Create a copy of abbreviation Abbrev.
+    void copyAbbrev(const DWARFAbbreviationDeclaration &Abbrev, bool hasODR);
+
+    uint32_t hashFullyQualifiedName(DWARFDie DIE, CompileUnit &U,
+                                    const DwarfLinkerObjFile &OF,
+                                    int RecurseDepth = 0);
+
+    /// Helper for cloneDIE.
+    void addObjCAccelerator(CompileUnit &Unit, const DIE *Die,
+                            DwarfStringPoolEntryRef Name,
+                            OffsetsStringPool &StringPool, bool SkipPubSection);
+  };
+
+  /// Assign an abbreviation number to \p Abbrev
+  void assignAbbrev(DIEAbbrev &Abbrev);
+
+  /// Compute and emit debug_ranges section for \p Unit, and
+  /// patch the attributes referencing it.
+  void patchRangesForUnit(const CompileUnit &Unit, DWARFContext &Dwarf,
+                          const DwarfLinkerObjFile &OF) const;
+
+  /// Generate and emit the DW_AT_ranges attribute for a compile_unit if it had
+  /// one.
+  void generateUnitRanges(CompileUnit &Unit) const;
+
+  /// Extract the line tables from the original dwarf, extract the relevant
+  /// parts according to the linked function ranges and emit the result in the
+  /// debug_line section.
+  void patchLineTableForUnit(CompileUnit &Unit, DWARFContext &OrigDwarf,
+                             const DwarfLinkerObjFile &OF);
+
+  /// Emit the accelerator entries for \p Unit.
+  void emitAcceleratorEntriesForUnit(CompileUnit &Unit);
+  void emitDwarfAcceleratorEntriesForUnit(CompileUnit &Unit);
+  void emitAppleAcceleratorEntriesForUnit(CompileUnit &Unit);
+
+  /// Patch the frame info for an object file and emit it.
+  void patchFrameInfoForObject(const DwarfLinkerObjFile &, RangesTy &Ranges,
+                               DWARFContext &, unsigned AddressSize);
+
+  /// FoldingSet that uniques the abbreviations.
+  FoldingSet<DIEAbbrev> AbbreviationsSet;
+
+  /// Storage for the unique Abbreviations.
+  /// This is passed to AsmPrinter::emitDwarfAbbrevs(), thus it cannot be
+  /// changed to a vector of unique_ptrs.
+  std::vector<std::unique_ptr<DIEAbbrev>> Abbreviations;
+
+  /// DIELoc objects that need to be destructed (but not freed!).
+  std::vector<DIELoc *> DIELocs;
+
+  /// DIEBlock objects that need to be destructed (but not freed!).
+  std::vector<DIEBlock *> DIEBlocks;
+
+  /// Allocator used for all the DIEValue objects.
+  BumpPtrAllocator DIEAlloc;
+  /// @}
+
+  Triple Triple;
+
+  DwarfEmitter *DwarfEmitter;
+  std::vector<LinkContext> ObjectContexts;
+
+  unsigned MaxDwarfVersion = 0;
+  unsigned MinDwarfVersion = std::numeric_limits<unsigned>::max();
+
+  bool AtLeastOneAppleAccelTable = false;
+  bool AtLeastOneDwarfAccelTable = false;
+
+  /// The CIEs that have been emitted in the output section. The actual CIE
+  /// data serves a the key to this StringMap, this takes care of comparing the
+  /// semantics of CIEs defined in different object files.
+  StringMap<uint32_t> EmittedCIEs;
+
+  /// Offset of the last CIE that has been emitted in the output
+  /// debug_frame section.
+  uint32_t LastCIEOffset = 0;
+
+  /// Apple accelerator tables.
+  AccelTable<DWARF5AccelTableStaticData> DebugNames;
+  AccelTable<AppleAccelTableStaticOffsetData> AppleNames;
+  AccelTable<AppleAccelTableStaticOffsetData> AppleNamespaces;
+  AccelTable<AppleAccelTableStaticOffsetData> AppleObjc;
+  AccelTable<AppleAccelTableStaticTypeData> AppleTypes;
+
+  /// Mapping the PCM filename to the DwoId.
+  StringMap<uint64_t> ClangModules;
+
+  DwarfLinkerClient DwarfLinkerClientID;
+
+  std::function<StringRef(StringRef)> StringsTranslator = nullptr;
+
+  /// linking options
+  struct DWARFLinkerOptions {
+    /// Generate processing log to the standard output.
+    bool Verbose = false;
+
+    /// Skip emitting output
+    bool NoOutput = false;
+
+    /// Do not unique types according to ODR
+    bool NoODR = false;
+
+    /// Update
+    bool Update = false;
+
+    /// Number of threads.
+    unsigned Threads = 1;
+
+    /// The accelerator table kind
+    AccelTableKind TheAccelTableKind = AccelTableKind::Default;
+
+    /// Prepend path for the clang modules.
+    std::string PrependPath;
+
+    // warning handler
+    messageHandler WarningHandler = nullptr;
+
+    // error handler
+    messageHandler ErrorHandler = nullptr;
+
+    objFileLoader ObjFileLoader = nullptr;
+
+    /// A list of all .swiftinterface files referenced by the debug
+    /// info, mapping Module name to path on disk. The entries need to
+    /// be uniqued and sorted and there are only few entries expected
+    /// per compile unit, which is why this is a std::map.
+    /// this is dsymutil specific fag.
+    swiftInterfacesMap *ParseableSwiftInterfaces = nullptr;
+  } Options;
+};
+
 } // end namespace llvm
 
 #endif // LLVM_DWARFLINKER_DWARFLINKER_H

llvm/tools/dsymutil/DwarfLinkerForBinary.h

@@ -17,26 +17,20 @@
 #include "llvm/DWARFLinker/DWARFLinkerCompileUnit.h"
 #include "llvm/DWARFLinker/DWARFLinkerDeclContext.h"
 #include "llvm/DebugInfo/DWARF/DWARFContext.h"
+#include "llvm/Remarks/RemarkFormat.h"
+#include "llvm/Remarks/RemarkLinker.h"
 
 namespace llvm {
 namespace dsymutil {
 
-using UnitListTy = std::vector<std::unique_ptr<CompileUnit>>;
+/// The core of the Dsymutil Dwarf linking logic.
-
-/// The core of the Dwarf linking logic.
 ///
 /// The link of the dwarf information from the object files will be
-/// driven by the selection of 'root DIEs', which are DIEs that
+/// driven by DWARFLinker. DwarfLinkerForBinary reads DebugMap objects
-/// describe variables or functions that are present in the linked
+/// and pass information to the DWARFLinker. DWARFLinker
-/// binary (and thus have entries in the debug map). All the debug
+/// optimizes DWARF taking into account valid relocations.
-/// information that will be linked (the DIEs, but also the line
+/// Finally, optimized DWARF is passed to DwarfLinkerForBinary through
-/// tables, ranges, ...) is derived from that set of root DIEs.
+/// DWARFEmitter interface.
-///
-/// The root DIEs are identified because they contain relocations that
-/// correspond to a debug map entry at specific places (the low_pc for
-/// a function, the location for a variable). These relocations are
-/// called ValidRelocs in the DwarfLinker and are gathered as a very
-/// first step when we start processing a DebugMapObject.
 class DwarfLinkerForBinary {
 public:
   DwarfLinkerForBinary(raw_fd_ostream &OutFile, BinaryHolder &BinHolder,
@@ -46,7 +40,7 @@ public:
   /// Link the contents of the DebugMap.
   bool link(const DebugMap &);
 
-  void reportWarning(const Twine &Warning, const DebugMapObject &DMO,
+  void reportWarning(const Twine &Warning, StringRef Context,
                      const DWARFDie *DIE = nullptr) const;
 
   /// Flags passed to DwarfLinker::lookForDIEsToKeep
@@ -60,21 +54,9 @@ public:
   };
 
 private:
-  /// Remembers the oldest and newest DWARF version we've seen in a unit.
-  void updateDwarfVersion(unsigned Version) {
-    MaxDwarfVersion = std::max(MaxDwarfVersion, Version);
-    MinDwarfVersion = std::min(MinDwarfVersion, Version);
-  }
-
-  /// Remembers the kinds of accelerator tables we've seen in a unit.
-  void updateAccelKind(DWARFContext &Dwarf);
-
-  /// Emit warnings as Dwarf compile units to leave a trail after linking.
-  bool emitPaperTrailWarnings(const DebugMapObject &DMO, const DebugMap &Map,
-                              OffsetsStringPool &StringPool);
 
   /// Keeps track of relocations.
-  class RelocationManager : public AddressesMap {
+  class AddressManager : public AddressesMap {
     struct ValidReloc {
       uint64_t Offset;
       uint32_t Size;
@@ -105,8 +87,8 @@ private:
     RangesTy AddressRanges;
 
   public:
-    RelocationManager(DwarfLinkerForBinary &Linker,
+    AddressManager(DwarfLinkerForBinary &Linker, const object::ObjectFile &Obj,
-                      const object::ObjectFile &Obj, const DebugMapObject &DMO)
+                   const DebugMapObject &DMO)
         : Linker(Linker) {
       findValidRelocsInDebugInfo(Obj, DMO);
 
@@ -135,7 +117,7 @@ private:
               int64_t(Mapping.BinaryAddress) - *Mapping.ObjectAddress);
       }
     }
-    virtual ~RelocationManager() override { clear(); }
+    virtual ~AddressManager() override { clear(); }
 
     virtual bool areRelocationsResolved() const override { return true; }
 
@@ -176,315 +158,7 @@ private:
     }
   };
 
-  /// Keeps track of data associated with one object during linking.
+private:
-  struct LinkContext {
-    DwarfLinkerForBinary &Linker;
-    DebugMapObject &DMO;
-    const object::ObjectFile *ObjectFile = nullptr;
-    std::unique_ptr<RelocationManager> RelocMgr;
-    std::unique_ptr<DWARFContext> DwarfContext;
-    RangesTy Ranges;
-    UnitListTy CompileUnits;
-
-    LinkContext(const DebugMap &Map, DwarfLinkerForBinary &Linker,
-                DebugMapObject &DMO)
-        : Linker(Linker), DMO(DMO) {
-      // Swift ASTs are not object files.
-      if (DMO.getType() == MachO::N_AST) {
-        ObjectFile = nullptr;
-        return;
-      }
-      if (auto ErrOrObj = Linker.loadObject(DMO, Map)) {
-        ObjectFile = &*ErrOrObj;
-        DwarfContext = DWARFContext::create(*ObjectFile);
-        RelocMgr.reset(new RelocationManager(Linker, *ObjectFile, DMO));
-      }
-    }
-
-    /// Clear part of the context that's no longer needed when we're done with
-    /// the debug object.
-    void Clear() {
-      DwarfContext.reset(nullptr);
-      CompileUnits.clear();
-      Ranges.clear();
-      RelocMgr->clear();
-    }
-  };
-
-  /// Called at the start of a debug object link.
-  void startDebugObject(LinkContext &Context);
-
-  /// Called at the end of a debug object link.
-  void endDebugObject(LinkContext &Context);
-
-  /// \defgroup FindRootDIEs Find DIEs corresponding to debug map entries.
-  ///
-  /// @{
-  /// Recursively walk the \p DIE tree and look for DIEs to
-  /// keep. Store that information in \p CU's DIEInfo.
-  ///
-  /// The return value indicates whether the DIE is incomplete.
-  void lookForDIEsToKeep(RelocationManager &RelocMgr, RangesTy &Ranges,
-                         const UnitListTy &Units, const DWARFDie &DIE,
-                         const DebugMapObject &DMO, CompileUnit &CU,
-                         unsigned Flags);
-
-  /// If this compile unit is really a skeleton CU that points to a
-  /// clang module, register it in ClangModules and return true.
-  ///
-  /// A skeleton CU is a CU without children, a DW_AT_gnu_dwo_name
-  /// pointing to the module, and a DW_AT_gnu_dwo_id with the module
-  /// hash.
-  bool registerModuleReference(DWARFDie CUDie, const DWARFUnit &Unit,
-                               DebugMap &ModuleMap, const DebugMapObject &DMO,
-                               RangesTy &Ranges,
-                               OffsetsStringPool &OffsetsStringPool,
-                               UniquingStringPool &UniquingStringPoolStringPool,
-                               DeclContextTree &ODRContexts,
-                               uint64_t ModulesEndOffset, unsigned &UnitID,
-                               bool IsLittleEndian, unsigned Indent = 0,
-                               bool Quiet = false);
-
-  /// Recursively add the debug info in this clang module .pcm
-  /// file (and all the modules imported by it in a bottom-up fashion)
-  /// to Units.
-  Error loadClangModule(DWARFDie CUDie, StringRef FilePath,
-                        StringRef ModuleName, uint64_t DwoId,
-                        DebugMap &ModuleMap, const DebugMapObject &DMO,
-                        RangesTy &Ranges, OffsetsStringPool &OffsetsStringPool,
-                        UniquingStringPool &UniquingStringPool,
-                        DeclContextTree &ODRContexts, uint64_t ModulesEndOffset,
-                        unsigned &UnitID, bool IsLittleEndian,
-                        unsigned Indent = 0, bool Quiet = false);
-
-  /// Mark the passed DIE as well as all the ones it depends on as kept.
-  void keepDIEAndDependencies(RelocationManager &RelocMgr, RangesTy &Ranges,
-                              const UnitListTy &Units, const DWARFDie &DIE,
-                              CompileUnit::DIEInfo &MyInfo,
-                              const DebugMapObject &DMO, CompileUnit &CU,
-                              bool UseODR);
-
-  unsigned shouldKeepDIE(RelocationManager &RelocMgr, RangesTy &Ranges,
-                         const DWARFDie &DIE, const DebugMapObject &DMO,
-                         CompileUnit &Unit, CompileUnit::DIEInfo &MyInfo,
-                         unsigned Flags);
-
-  /// Check if a variable describing DIE should be kept.
-  /// \returns updated TraversalFlags.
-  unsigned shouldKeepVariableDIE(RelocationManager &RelocMgr,
-                                 const DWARFDie &DIE, CompileUnit &Unit,
-                                 CompileUnit::DIEInfo &MyInfo, unsigned Flags);
-
-  unsigned shouldKeepSubprogramDIE(RelocationManager &RelocMgr,
-                                   RangesTy &Ranges, const DWARFDie &DIE,
-                                   const DebugMapObject &DMO, CompileUnit &Unit,
-                                   CompileUnit::DIEInfo &MyInfo,
-                                   unsigned Flags);
-
-  bool hasValidRelocation(uint32_t StartOffset, uint32_t EndOffset,
-                          CompileUnit::DIEInfo &Info);
-  /// @}
-
-  /// \defgroup Linking Methods used to link the debug information
-  ///
-  /// @{
-
-  class DIECloner {
-    DwarfLinkerForBinary &Linker;
-    RelocationManager &RelocMgr;
-
-    /// Allocator used for all the DIEValue objects.
-    BumpPtrAllocator &DIEAlloc;
-
-    std::vector<std::unique_ptr<CompileUnit>> &CompileUnits;
-    LinkOptions Options;
-
-  public:
-    DIECloner(DwarfLinkerForBinary &Linker, RelocationManager &RelocMgr,
-              BumpPtrAllocator &DIEAlloc,
-              std::vector<std::unique_ptr<CompileUnit>> &CompileUnits,
-              LinkOptions &Options)
-        : Linker(Linker), RelocMgr(RelocMgr), DIEAlloc(DIEAlloc),
-          CompileUnits(CompileUnits), Options(Options) {}
-
-    /// Recursively clone \p InputDIE into an tree of DIE objects
-    /// where useless (as decided by lookForDIEsToKeep()) bits have been
-    /// stripped out and addresses have been rewritten according to the
-    /// debug map.
-    ///
-    /// \param OutOffset is the offset the cloned DIE in the output
-    /// compile unit.
-    /// \param PCOffset (while cloning a function scope) is the offset
-    /// applied to the entry point of the function to get the linked address.
-    /// \param Die the output DIE to use, pass NULL to create one.
-    /// \returns the root of the cloned tree or null if nothing was selected.
-    DIE *cloneDIE(const DWARFDie &InputDIE, const DebugMapObject &DMO,
-                  CompileUnit &U, OffsetsStringPool &StringPool,
-                  int64_t PCOffset, uint32_t OutOffset, unsigned Flags,
-                  bool IsLittleEndian, DIE *Die = nullptr);
-
-    /// Construct the output DIE tree by cloning the DIEs we
-    /// chose to keep above. If there are no valid relocs, then there's
-    /// nothing to clone/emit.
-    void cloneAllCompileUnits(DWARFContext &DwarfContext,
-                              const DebugMapObject &DMO, RangesTy &Ranges,
-                              OffsetsStringPool &StringPool,
-                              bool IsLittleEndian);
-
-  private:
-    using AttributeSpec = DWARFAbbreviationDeclaration::AttributeSpec;
-
-    /// Information gathered and exchanged between the various
-    /// clone*Attributes helpers about the attributes of a particular DIE.
-    struct AttributesInfo {
-      /// Names.
-      DwarfStringPoolEntryRef Name, MangledName, NameWithoutTemplate;
-
-      /// Offsets in the string pool.
-      uint32_t NameOffset = 0;
-      uint32_t MangledNameOffset = 0;
-
-      /// Value of AT_low_pc in the input DIE
-      uint64_t OrigLowPc = std::numeric_limits<uint64_t>::max();
-
-      /// Value of AT_high_pc in the input DIE
-      uint64_t OrigHighPc = 0;
-
-      /// Offset to apply to PC addresses inside a function.
-      int64_t PCOffset = 0;
-
-      /// Does the DIE have a low_pc attribute?
-      bool HasLowPc = false;
-
-      /// Does the DIE have a ranges attribute?
-      bool HasRanges = false;
-
-      /// Is this DIE only a declaration?
-      bool IsDeclaration = false;
-
-      AttributesInfo() = default;
-    };
-
-    /// Helper for cloneDIE.
-    unsigned cloneAttribute(DIE &Die, const DWARFDie &InputDIE,
-                            const DebugMapObject &DMO, CompileUnit &U,
-                            OffsetsStringPool &StringPool,
-                            const DWARFFormValue &Val,
-                            const AttributeSpec AttrSpec, unsigned AttrSize,
-                            AttributesInfo &AttrInfo, bool IsLittleEndian);
-
-    /// Clone a string attribute described by \p AttrSpec and add
-    /// it to \p Die.
-    /// \returns the size of the new attribute.
-    unsigned cloneStringAttribute(DIE &Die, AttributeSpec AttrSpec,
-                                  const DWARFFormValue &Val, const DWARFUnit &U,
-                                  OffsetsStringPool &StringPool,
-                                  AttributesInfo &Info);
-
-    /// Clone an attribute referencing another DIE and add
-    /// it to \p Die.
-    /// \returns the size of the new attribute.
-    unsigned cloneDieReferenceAttribute(DIE &Die, const DWARFDie &InputDIE,
-                                        AttributeSpec AttrSpec,
-                                        unsigned AttrSize,
-                                        const DWARFFormValue &Val,
-                                        const DebugMapObject &DMO,
-                                        CompileUnit &Unit);
-
-    /// Clone a DWARF expression that may be referencing another DIE.
-    void cloneExpression(DataExtractor &Data, DWARFExpression Expression,
-                         const DebugMapObject &DMO, CompileUnit &Unit,
-                         SmallVectorImpl<uint8_t> &OutputBuffer);
-
-    /// Clone an attribute referencing another DIE and add
-    /// it to \p Die.
-    /// \returns the size of the new attribute.
-    unsigned cloneBlockAttribute(DIE &Die, const DebugMapObject &DMO,
-                                 CompileUnit &Unit, AttributeSpec AttrSpec,
-                                 const DWARFFormValue &Val, unsigned AttrSize,
-                                 bool IsLittleEndian);
-
-    /// Clone an attribute referencing another DIE and add
-    /// it to \p Die.
-    /// \returns the size of the new attribute.
-    unsigned cloneAddressAttribute(DIE &Die, AttributeSpec AttrSpec,
-                                   const DWARFFormValue &Val,
-                                   const CompileUnit &Unit,
-                                   AttributesInfo &Info);
-
-    /// Clone a scalar attribute  and add it to \p Die.
-    /// \returns the size of the new attribute.
-    unsigned cloneScalarAttribute(DIE &Die, const DWARFDie &InputDIE,
-                                  const DebugMapObject &DMO, CompileUnit &U,
-                                  AttributeSpec AttrSpec,
-                                  const DWARFFormValue &Val, unsigned AttrSize,
-                                  AttributesInfo &Info);
-
-    /// Get the potential name and mangled name for the entity
-    /// described by \p Die and store them in \Info if they are not
-    /// already there.
-    /// \returns is a name was found.
-    bool getDIENames(const DWARFDie &Die, AttributesInfo &Info,
-                     OffsetsStringPool &StringPool, bool StripTemplate = false);
-
-    /// Create a copy of abbreviation Abbrev.
-    void copyAbbrev(const DWARFAbbreviationDeclaration &Abbrev, bool hasODR);
-
-    uint32_t hashFullyQualifiedName(DWARFDie DIE, CompileUnit &U,
-                                    const DebugMapObject &DMO,
-                                    int RecurseDepth = 0);
-
-    /// Helper for cloneDIE.
-    void addObjCAccelerator(CompileUnit &Unit, const DIE *Die,
-                            DwarfStringPoolEntryRef Name,
-                            OffsetsStringPool &StringPool, bool SkipPubSection);
-  };
-
-  /// Assign an abbreviation number to \p Abbrev
-  void assignAbbrev(DIEAbbrev &Abbrev);
-
-  /// Compute and emit debug_ranges section for \p Unit, and
-  /// patch the attributes referencing it.
-  void patchRangesForUnit(const CompileUnit &Unit, DWARFContext &Dwarf,
-                          const DebugMapObject &DMO) const;
-
-  /// Generate and emit the DW_AT_ranges attribute for a compile_unit if it had
-  /// one.
-  void generateUnitRanges(CompileUnit &Unit) const;
-
-  /// Extract the line tables from the original dwarf, extract the relevant
-  /// parts according to the linked function ranges and emit the result in the
-  /// debug_line section.
-  void patchLineTableForUnit(CompileUnit &Unit, DWARFContext &OrigDwarf,
-                             RangesTy &Ranges, const DebugMapObject &DMO);
-
-  /// Emit the accelerator entries for \p Unit.
-  void emitAcceleratorEntriesForUnit(CompileUnit &Unit);
-  void emitDwarfAcceleratorEntriesForUnit(CompileUnit &Unit);
-  void emitAppleAcceleratorEntriesForUnit(CompileUnit &Unit);
-
-  /// Patch the frame info for an object file and emit it.
-  void patchFrameInfoForObject(const DebugMapObject &, RangesTy &Ranges,
-                               DWARFContext &, unsigned AddressSize);
-
-  /// FoldingSet that uniques the abbreviations.
-  FoldingSet<DIEAbbrev> AbbreviationsSet;
-
-  /// Storage for the unique Abbreviations.
-  /// This is passed to AsmPrinter::emitDwarfAbbrevs(), thus it cannot be
-  /// changed to a vector of unique_ptrs.
-  std::vector<std::unique_ptr<DIEAbbrev>> Abbreviations;
-
-  /// DIELoc objects that need to be destructed (but not freed!).
-  std::vector<DIELoc *> DIELocs;
-
-  /// DIEBlock objects that need to be destructed (but not freed!).
-  std::vector<DIEBlock *> DIEBlocks;
-
-  /// Allocator used for all the DIEValue objects.
-  BumpPtrAllocator DIEAlloc;
-  /// @}
-
   /// \defgroup Helpers Various helper methods.
   ///
   /// @{
@@ -492,38 +166,16 @@ private:
 
   /// Attempt to load a debug object from disk.
   ErrorOr<const object::ObjectFile &> loadObject(const DebugMapObject &Obj,
-                                                 const DebugMap &Map);
+                                                 const Triple &triple);
-  /// @}
+  ErrorOr<DwarfLinkerObjFile &> loadObject(const DebugMapObject &Obj,
+                                           const DebugMap &DebugMap,
+                                           remarks::RemarkLinker &RL);
 
   raw_fd_ostream &OutFile;
   BinaryHolder &BinHolder;
   LinkOptions Options;
   std::unique_ptr<DwarfStreamer> Streamer;
-
+  std::vector<std::unique_ptr<DwarfLinkerObjFile>> ObjectsForLinking;
-  unsigned MaxDwarfVersion = 0;
-  unsigned MinDwarfVersion = std::numeric_limits<unsigned>::max();
-
-  bool AtLeastOneAppleAccelTable = false;
-  bool AtLeastOneDwarfAccelTable = false;
-
-  /// The CIEs that have been emitted in the output section. The actual CIE
-  /// data serves a the key to this StringMap, this takes care of comparing the
-  /// semantics of CIEs defined in different object files.
-  StringMap<uint32_t> EmittedCIEs;
-
-  /// Offset of the last CIE that has been emitted in the output
-  /// debug_frame section.
-  uint32_t LastCIEOffset = 0;
-
-  /// Apple accelerator tables.
-  AccelTable<DWARF5AccelTableStaticData> DebugNames;
-  AccelTable<AppleAccelTableStaticOffsetData> AppleNames;
-  AccelTable<AppleAccelTableStaticOffsetData> AppleNamespaces;
-  AccelTable<AppleAccelTableStaticOffsetData> AppleObjc;
-  AccelTable<AppleAccelTableStaticTypeData> AppleTypes;
-
-  /// Mapping the PCM filename to the DwoId.
-  StringMap<uint64_t> ClangModules;
 
   /// A list of all .swiftinterface files referenced by the debug
   /// info, mapping Module name to path on disk. The entries need to

llvm/tools/dsymutil/DwarfStreamer.cpp

@@ -784,12 +784,16 @@ void DwarfStreamer::emitPubSectionForUnit(
 
 /// Emit .debug_pubnames for \p Unit.
 void DwarfStreamer::emitPubNamesForUnit(const CompileUnit &Unit) {
+  if (Options.Minimize)
+    return;
   emitPubSectionForUnit(MC->getObjectFileInfo()->getDwarfPubNamesSection(),
                         "names", Unit, Unit.getPubnames());
 }
 
 /// Emit .debug_pubtypes for \p Unit.
 void DwarfStreamer::emitPubTypesForUnit(const CompileUnit &Unit) {
+  if (Options.Minimize)
+    return;
   emitPubSectionForUnit(MC->getObjectFileInfo()->getDwarfPubTypesSection(),
                         "types", Unit, Unit.getPubtypes());
 }

llvm/tools/dsymutil/LinkUtils.h

@@ -15,6 +15,7 @@
 #include "llvm/Remarks/RemarkFormat.h"
 #include "llvm/Support/WithColor.h"
 
+#include "llvm/DWARFLinker/DWARFLinker.h"
 #include <string>
 
 namespace llvm {
@@ -25,13 +26,6 @@ enum class OutputFileType {
   Assembly,
 };
 
-/// The kind of accelerator tables we should emit.
-enum class AccelTableKind {
-  Apple,   ///< .apple_names, .apple_namespaces, .apple_types, .apple_objc.
-  Dwarf,   ///< DWARF v5 .debug_names.
-  Default, ///< Dwarf for DWARF5 or later, Apple otherwise.
-};
-
 struct LinkOptions {
   /// Verbosity
   bool Verbose = false;