text: //===- lib/MC/MCAsmStreamer.cpp - Text Assembly Output ----------*- C++ -*-===//
  //
  // 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
  //
  //===----------------------------------------------------------------------===//
  
  #include "llvm/ADT/Optional.h"
  #include "llvm/ADT/STLExtras.h"
  #include "llvm/ADT/SmallString.h"
  #include "llvm/ADT/StringExtras.h"
  #include "llvm/ADT/Twine.h"
  #include "llvm/DebugInfo/CodeView/SymbolRecord.h"
  #include "llvm/MC/MCAsmBackend.h"
  #include "llvm/MC/MCAsmInfo.h"
  #include "llvm/MC/MCAssembler.h"
  #include "llvm/MC/MCCodeEmitter.h"
  #include "llvm/MC/MCCodeView.h"
  #include "llvm/MC/MCContext.h"
  #include "llvm/MC/MCExpr.h"
  #include "llvm/MC/MCFixupKindInfo.h"
  #include "llvm/MC/MCInst.h"
  #include "llvm/MC/MCInstPrinter.h"
  #include "llvm/MC/MCObjectFileInfo.h"
  #include "llvm/MC/MCObjectWriter.h"
  #include "llvm/MC/MCRegister.h"
  #include "llvm/MC/MCRegisterInfo.h"
  #include "llvm/MC/MCSectionMachO.h"
  #include "llvm/MC/MCStreamer.h"
  #include "llvm/Support/ErrorHandling.h"
  #include "llvm/Support/Format.h"
  #include "llvm/Support/FormattedStream.h"
  #include "llvm/Support/LEB128.h"
  #include "llvm/Support/MathExtras.h"
  #include "llvm/Support/Path.h"
  #include "llvm/Support/TargetRegistry.h"
  #include <cctype>
  
  using namespace llvm;
  
  namespace {
  
  class MCAsmStreamer final : public MCStreamer {
    std::unique_ptr<formatted_raw_ostream> OSOwner;
    formatted_raw_ostream &OS;
    const MCAsmInfo *MAI;
    std::unique_ptr<MCInstPrinter> InstPrinter;
    std::unique_ptr<MCAssembler> Assembler;
  
    SmallString<128> ExplicitCommentToEmit;
    SmallString<128> CommentToEmit;
    raw_svector_ostream CommentStream;
    raw_null_ostream NullStream;
  
    unsigned IsVerboseAsm : 1;
    unsigned ShowInst : 1;
    unsigned UseDwarfDirectory : 1;
  
    void EmitRegisterName(int64_t Register);
    void EmitCFIStartProcImpl(MCDwarfFrameInfo &Frame) override;
    void EmitCFIEndProcImpl(MCDwarfFrameInfo &Frame) override;
  
  public:
    MCAsmStreamer(MCContext &Context, std::unique_ptr<formatted_raw_ostream> os,
                  bool isVerboseAsm, bool useDwarfDirectory,
                  MCInstPrinter *printer, std::unique_ptr<MCCodeEmitter> emitter,
                  std::unique_ptr<MCAsmBackend> asmbackend, bool showInst)
        : MCStreamer(Context), OSOwner(std::move(os)), OS(*OSOwner),
          MAI(Context.getAsmInfo()), InstPrinter(printer),
          Assembler(std::make_unique<MCAssembler>(
              Context, std::move(asmbackend), std::move(emitter),
              (asmbackend) ? asmbackend->createObjectWriter(NullStream)
                           : nullptr)),
          CommentStream(CommentToEmit), IsVerboseAsm(isVerboseAsm),
          ShowInst(showInst), UseDwarfDirectory(useDwarfDirectory) {
      assert(InstPrinter);
      if (IsVerboseAsm)
          InstPrinter->setCommentStream(CommentStream);
    }
  
    MCAssembler &getAssembler() { return *Assembler; }
    MCAssembler *getAssemblerPtr() override { return nullptr; }
  
    inline void EmitEOL() {
      // Dump Explicit Comments here.
      emitExplicitComments();
      // If we don't have any comments, just emit a \n.
      if (!IsVerboseAsm) {
        OS << '\n';
        return;
      }
      EmitCommentsAndEOL();
    }
  
    void EmitSyntaxDirective() override;
  
    void EmitCommentsAndEOL();
  
    /// Return true if this streamer supports verbose assembly at all.
    bool isVerboseAsm() const override { return IsVerboseAsm; }
  
    /// Do we support EmitRawText?
    bool hasRawTextSupport() const override { return true; }
  
    /// Add a comment that can be emitted to the generated .s file to make the
    /// output of the compiler more readable. This only affects the MCAsmStreamer
    /// and only when verbose assembly output is enabled.
    void AddComment(const Twine &T, bool EOL = true) override;
  
    /// Add a comment showing the encoding of an instruction.
    void AddEncodingComment(const MCInst &Inst, const MCSubtargetInfo &);
  
    /// Return a raw_ostream that comments can be written to.
    /// Unlike AddComment, you are required to terminate comments with \n if you
    /// use this method.
    raw_ostream &GetCommentOS() override {
      if (!IsVerboseAsm)
        return nulls();  // Discard comments unless in verbose asm mode.
      return CommentStream;
    }
  
    void emitRawComment(const Twine &T, bool TabPrefix = true) override;
  
    void addExplicitComment(const Twine &T) override;
    void emitExplicitComments() override;
  
    /// Emit a blank line to a .s file to pretty it up.
    void AddBlankLine() override {
      EmitEOL();
    }
  
    /// @name MCStreamer Interface
    /// @{
  
    void ChangeSection(MCSection *Section, const MCExpr *Subsection) override;
  
    void emitELFSymverDirective(StringRef AliasName,
                                const MCSymbol *Aliasee) override;
  
    void EmitLOHDirective(MCLOHType Kind, const MCLOHArgs &Args) override;
    void EmitLabel(MCSymbol *Symbol, SMLoc Loc = SMLoc()) override;
  
    void EmitAssemblerFlag(MCAssemblerFlag Flag) override;
    void EmitLinkerOptions(ArrayRef<std::string> Options) override;
    void EmitDataRegion(MCDataRegionType Kind) override;
    void EmitVersionMin(MCVersionMinType Kind, unsigned Major, unsigned Minor,
                        unsigned Update, VersionTuple SDKVersion) override;
    void EmitBuildVersion(unsigned Platform, unsigned Major, unsigned Minor,
                          unsigned Update, VersionTuple SDKVersion) override;
    void EmitThumbFunc(MCSymbol *Func) override;
  
    void EmitAssignment(MCSymbol *Symbol, const MCExpr *Value) override;
    void EmitWeakReference(MCSymbol *Alias, const MCSymbol *Symbol) override;
    bool EmitSymbolAttribute(MCSymbol *Symbol, MCSymbolAttr Attribute) override;
  
    void EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue) override;
    void BeginCOFFSymbolDef(const MCSymbol *Symbol) override;
    void EmitCOFFSymbolStorageClass(int StorageClass) override;
    void EmitCOFFSymbolType(int Type) override;
    void EndCOFFSymbolDef() override;
    void EmitCOFFSafeSEH(MCSymbol const *Symbol) override;
    void EmitCOFFSymbolIndex(MCSymbol const *Symbol) override;
    void EmitCOFFSectionIndex(MCSymbol const *Symbol) override;
    void EmitCOFFSecRel32(MCSymbol const *Symbol, uint64_t Offset) override;
    void EmitCOFFImgRel32(MCSymbol const *Symbol, int64_t Offset) override;
    void EmitXCOFFLocalCommonSymbol(MCSymbol *LabelSym, uint64_t Size,
                                    MCSymbol *CsectSym,
                                    unsigned ByteAlign) override;
    void emitELFSize(MCSymbol *Symbol, const MCExpr *Value) override;
    void EmitCommonSymbol(MCSymbol *Symbol, uint64_t Size,
                          unsigned ByteAlignment) override;
  
    /// Emit a local common (.lcomm) symbol.
    ///
    /// @param Symbol - The common symbol to emit.
    /// @param Size - The size of the common symbol.
    /// @param ByteAlignment - The alignment of the common symbol in bytes.
    void EmitLocalCommonSymbol(MCSymbol *Symbol, uint64_t Size,
                               unsigned ByteAlignment) override;
  
    void EmitZerofill(MCSection *Section, MCSymbol *Symbol = nullptr,
                      uint64_t Size = 0, unsigned ByteAlignment = 0,
                      SMLoc Loc = SMLoc()) override;
  
    void EmitTBSSSymbol(MCSection *Section, MCSymbol *Symbol, uint64_t Size,
                        unsigned ByteAlignment = 0) override;
  
    void EmitBinaryData(StringRef Data) override;
  
    void EmitBytes(StringRef Data) override;
  
    void EmitValueImpl(const MCExpr *Value, unsigned Size,
                       SMLoc Loc = SMLoc()) override;
    void EmitIntValue(uint64_t Value, unsigned Size) override;
    void EmitIntValueInHex(uint64_t Value, unsigned Size) override;
  
    void EmitULEB128Value(const MCExpr *Value) override;
  
    void EmitSLEB128Value(const MCExpr *Value) override;
  
    void EmitDTPRel32Value(const MCExpr *Value) override;
    void EmitDTPRel64Value(const MCExpr *Value) override;
    void EmitTPRel32Value(const MCExpr *Value) override;
    void EmitTPRel64Value(const MCExpr *Value) override;
  
    void EmitGPRel64Value(const MCExpr *Value) override;
  
    void EmitGPRel32Value(const MCExpr *Value) override;
  
    void emitFill(const MCExpr &NumBytes, uint64_t FillValue,
                  SMLoc Loc = SMLoc()) override;
  
    void emitFill(const MCExpr &NumValues, int64_t Size, int64_t Expr,
                  SMLoc Loc = SMLoc()) override;
  
    void EmitValueToAlignment(unsigned ByteAlignment, int64_t Value = 0,
                              unsigned ValueSize = 1,
                              unsigned MaxBytesToEmit = 0) override;
  
    void EmitCodeAlignment(unsigned ByteAlignment,
                           unsigned MaxBytesToEmit = 0) override;
  
    void emitValueToOffset(const MCExpr *Offset,
                           unsigned char Value,
                           SMLoc Loc) override;
  
    void EmitFileDirective(StringRef Filename) override;
    Expected<unsigned> tryEmitDwarfFileDirective(unsigned FileNo,
                                                 StringRef Directory,
                                                 StringRef Filename,
                                                 Optional<MD5::MD5Result> Checksum = None,
                                                 Optional<StringRef> Source = None,
                                                 unsigned CUID = 0) override;
    void emitDwarfFile0Directive(StringRef Directory, StringRef Filename,
                                 Optional<MD5::MD5Result> Checksum,
                                 Optional<StringRef> Source,
                                 unsigned CUID = 0) override;
    void EmitDwarfLocDirective(unsigned FileNo, unsigned Line,
                               unsigned Column, unsigned Flags,
                               unsigned Isa, unsigned Discriminator,
                               StringRef FileName) override;
    MCSymbol *getDwarfLineTableSymbol(unsigned CUID) override;
  
    bool EmitCVFileDirective(unsigned FileNo, StringRef Filename,
                             ArrayRef<uint8_t> Checksum,
                             unsigned ChecksumKind) override;
    bool EmitCVFuncIdDirective(unsigned FuncId) override;
    bool EmitCVInlineSiteIdDirective(unsigned FunctionId, unsigned IAFunc,
                                     unsigned IAFile, unsigned IALine,
                                     unsigned IACol, SMLoc Loc) override;
    void EmitCVLocDirective(unsigned FunctionId, unsigned FileNo, unsigned Line,
                            unsigned Column, bool PrologueEnd, bool IsStmt,
                            StringRef FileName, SMLoc Loc) override;
    void EmitCVLinetableDirective(unsigned FunctionId, const MCSymbol *FnStart,
                                  const MCSymbol *FnEnd) override;
    void EmitCVInlineLinetableDirective(unsigned PrimaryFunctionId,
                                        unsigned SourceFileId,
                                        unsigned SourceLineNum,
                                        const MCSymbol *FnStartSym,
                                        const MCSymbol *FnEndSym) override;
  
    void PrintCVDefRangePrefix(
        ArrayRef<std::pair<const MCSymbol *, const MCSymbol *>> Ranges);
  
    void EmitCVDefRangeDirective(
        ArrayRef<std::pair<const MCSymbol *, const MCSymbol *>> Ranges,
        codeview::DefRangeRegisterRelHeader DRHdr) override;
  
    void EmitCVDefRangeDirective(
        ArrayRef<std::pair<const MCSymbol *, const MCSymbol *>> Ranges,
        codeview::DefRangeSubfieldRegisterHeader DRHdr) override;
  
    void EmitCVDefRangeDirective(
        ArrayRef<std::pair<const MCSymbol *, const MCSymbol *>> Ranges,
        codeview::DefRangeRegisterHeader DRHdr) override;
  
    void EmitCVDefRangeDirective(
        ArrayRef<std::pair<const MCSymbol *, const MCSymbol *>> Ranges,
        codeview::DefRangeFramePointerRelHeader DRHdr) override;
  
    void EmitCVStringTableDirective() override;
    void EmitCVFileChecksumsDirective() override;
    void EmitCVFileChecksumOffsetDirective(unsigned FileNo) override;
    void EmitCVFPOData(const MCSymbol *ProcSym, SMLoc L) override;
  
    void EmitIdent(StringRef IdentString) override;
    void EmitCFIBKeyFrame() override;
    void EmitCFISections(bool EH, bool Debug) override;
    void EmitCFIDefCfa(int64_t Register, int64_t Offset) override;
    void EmitCFIDefCfaOffset(int64_t Offset) override;
    void EmitCFIDefCfaRegister(int64_t Register) override;
    void EmitCFIOffset(int64_t Register, int64_t Offset) override;
    void EmitCFIPersonality(const MCSymbol *Sym, unsigned Encoding) override;
    void EmitCFILsda(const MCSymbol *Sym, unsigned Encoding) override;
    void EmitCFIRememberState() override;
    void EmitCFIRestoreState() override;
    void EmitCFIRestore(int64_t Register) override;
    void EmitCFISameValue(int64_t Register) override;
    void EmitCFIRelOffset(int64_t Register, int64_t Offset) override;
    void EmitCFIAdjustCfaOffset(int64_t Adjustment) override;
    void EmitCFIEscape(StringRef Values) override;
    void EmitCFIGnuArgsSize(int64_t Size) override;
    void EmitCFISignalFrame() override;
    void EmitCFIUndefined(int64_t Register) override;
    void EmitCFIRegister(int64_t Register1, int64_t Register2) override;
    void EmitCFIWindowSave() override;
    void EmitCFINegateRAState() override;
    void EmitCFIReturnColumn(int64_t Register) override;
  
    void EmitWinCFIStartProc(const MCSymbol *Symbol, SMLoc Loc) override;
    void EmitWinCFIEndProc(SMLoc Loc) override;
    void EmitWinCFIFuncletOrFuncEnd(SMLoc Loc) override;
    void EmitWinCFIStartChained(SMLoc Loc) override;
    void EmitWinCFIEndChained(SMLoc Loc) override;
    void EmitWinCFIPushReg(MCRegister Register, SMLoc Loc) override;
    void EmitWinCFISetFrame(MCRegister Register, unsigned Offset,
                            SMLoc Loc) override;
    void EmitWinCFIAllocStack(unsigned Size, SMLoc Loc) override;
    void EmitWinCFISaveReg(MCRegister Register, unsigned Offset,
                           SMLoc Loc) override;
    void EmitWinCFISaveXMM(MCRegister Register, unsigned Offset,
                           SMLoc Loc) override;
    void EmitWinCFIPushFrame(bool Code, SMLoc Loc) override;
    void EmitWinCFIEndProlog(SMLoc Loc) override;
  
    void EmitWinEHHandler(const MCSymbol *Sym, bool Unwind, bool Except,
                          SMLoc Loc) override;
    void EmitWinEHHandlerData(SMLoc Loc) override;
  
    void emitCGProfileEntry(const MCSymbolRefExpr *From,
                            const MCSymbolRefExpr *To, uint64_t Count) override;
  
    void EmitInstruction(const MCInst &Inst, const MCSubtargetInfo &STI) override;
  
    void EmitBundleAlignMode(unsigned AlignPow2) override;
    void EmitBundleLock(bool AlignToEnd) override;
    void EmitBundleUnlock() override;
  
    bool EmitRelocDirective(const MCExpr &Offset, StringRef Name,
                            const MCExpr *Expr, SMLoc Loc,
                            const MCSubtargetInfo &STI) override;
  
    void EmitAddrsig() override;
    void EmitAddrsigSym(const MCSymbol *Sym) override;
  
    /// If this file is backed by an assembly streamer, this dumps the specified
    /// string in the output .s file. This capability is indicated by the
    /// hasRawTextSupport() predicate.
    void EmitRawTextImpl(StringRef String) override;
  
    void FinishImpl() override;
  };
  
  } // end anonymous namespace.
  
  void MCAsmStreamer::AddComment(const Twine &T, bool EOL) {
    if (!IsVerboseAsm) return;
  
    T.toVector(CommentToEmit);
  
    if (EOL)
      CommentToEmit.push_back('\n'); // Place comment in a new line.
  }
  
  void MCAsmStreamer::EmitCommentsAndEOL() {
    if (CommentToEmit.empty() && CommentStream.GetNumBytesInBuffer() == 0) {
      OS << '\n';
      return;
    }
  
    StringRef Comments = CommentToEmit;
  
    assert(Comments.back() == '\n' &&
           "Comment array not newline terminated");
    do {
      // Emit a line of comments.
      OS.PadToColumn(MAI->getCommentColumn());
      size_t Position = Comments.find('\n');
      OS << MAI->getCommentString() << ' ' << Comments.substr(0, Position) <<'\n';
  
      Comments = Comments.substr(Position+1);
    } while (!Comments.empty());
  
    CommentToEmit.clear();
  }
  
  static inline int64_t truncateToSize(int64_t Value, unsigned Bytes) {
    assert(Bytes > 0 && Bytes <= 8 && "Invalid size!");
    return Value & ((uint64_t) (int64_t) -1 >> (64 - Bytes * 8));
  }
  
  void MCAsmStreamer::emitRawComment(const Twine &T, bool TabPrefix) {
    if (TabPrefix)
      OS << '\t';
    OS << MAI->getCommentString() << T;
    EmitEOL();
  }
  
  void MCAsmStreamer::addExplicitComment(const Twine &T) {
    StringRef c = T.getSingleStringRef();
    if (c.equals(StringRef(MAI->getSeparatorString())))
      return;
    if (c.startswith(StringRef("//"))) {
      ExplicitCommentToEmit.append("\t");
      ExplicitCommentToEmit.append(MAI->getCommentString());
      // drop //
      ExplicitCommentToEmit.append(c.slice(2, c.size()).str());
    } else if (c.startswith(StringRef("/*"))) {
      size_t p = 2, len = c.size() - 2;
      // emit each line in comment as separate newline.
      do {
        size_t newp = std::min(len, c.find_first_of("\r\n", p));
        ExplicitCommentToEmit.append("\t");
        ExplicitCommentToEmit.append(MAI->getCommentString());
        ExplicitCommentToEmit.append(c.slice(p, newp).str());
        // If we have another line in this comment add line
        if (newp < len)
          ExplicitCommentToEmit.append("\n");
        p = newp + 1;
      } while (p < len);
    } else if (c.startswith(StringRef(MAI->getCommentString()))) {
      ExplicitCommentToEmit.append("\t");
      ExplicitCommentToEmit.append(c.str());
    } else if (c.front() == '#') {
  
      ExplicitCommentToEmit.append("\t");
      ExplicitCommentToEmit.append(MAI->getCommentString());
      ExplicitCommentToEmit.append(c.slice(1, c.size()).str());
    } else
      assert(false && "Unexpected Assembly Comment");
    // full line comments immediately output
    if (c.back() == '\n')
      emitExplicitComments();
  }
  
  void MCAsmStreamer::emitExplicitComments() {
    StringRef Comments = ExplicitCommentToEmit;
    if (!Comments.empty())
      OS << Comments;
    ExplicitCommentToEmit.clear();
  }
  
  void MCAsmStreamer::ChangeSection(MCSection *Section,
                                    const MCExpr *Subsection) {
    assert(Section && "Cannot switch to a null section!");
    if (MCTargetStreamer *TS = getTargetStreamer()) {
      TS->changeSection(getCurrentSectionOnly(), Section, Subsection, OS);
    } else {
      Section->PrintSwitchToSection(
          *MAI, getContext().getObjectFileInfo()->getTargetTriple(), OS,
          Subsection);
    }
  }
  
  void MCAsmStreamer::emitELFSymverDirective(StringRef AliasName,
                                             const MCSymbol *Aliasee) {
    OS << ".symver ";
    Aliasee->print(OS, MAI);
    OS << ", " << AliasName;
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitLabel(MCSymbol *Symbol, SMLoc Loc) {
    MCStreamer::EmitLabel(Symbol, Loc);
  
    Symbol->print(OS, MAI);
    OS << MAI->getLabelSuffix();
  
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitLOHDirective(MCLOHType Kind, const MCLOHArgs &Args) {
    StringRef str = MCLOHIdToName(Kind);
  
  #ifndef NDEBUG
    int NbArgs = MCLOHIdToNbArgs(Kind);
    assert(NbArgs != -1 && ((size_t)NbArgs) == Args.size() && "Malformed LOH!");
    assert(str != "" && "Invalid LOH name");
  #endif
  
    OS << "\t" << MCLOHDirectiveName() << " " << str << "\t";
    bool IsFirst = true;
    for (const MCSymbol *Arg : Args) {
      if (!IsFirst)
        OS << ", ";
      IsFirst = false;
      Arg->print(OS, MAI);
    }
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitAssemblerFlag(MCAssemblerFlag Flag) {
    switch (Flag) {
    case MCAF_SyntaxUnified:         OS << "\t.syntax unified"; break;
    case MCAF_SubsectionsViaSymbols: OS << ".subsections_via_symbols"; break;
    case MCAF_Code16:                OS << '\t'<< MAI->getCode16Directive();break;
    case MCAF_Code32:                OS << '\t'<< MAI->getCode32Directive();break;
    case MCAF_Code64:                OS << '\t'<< MAI->getCode64Directive();break;
    }
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitLinkerOptions(ArrayRef<std::string> Options) {
    assert(!Options.empty() && "At least one option is required!");
    OS << "\t.linker_option \"" << Options[0] << '"';
    for (ArrayRef<std::string>::iterator it = Options.begin() + 1,
           ie = Options.end(); it != ie; ++it) {
      OS << ", " << '"' << *it << '"';
    }
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitDataRegion(MCDataRegionType Kind) {
    if (!MAI->doesSupportDataRegionDirectives())
      return;
    switch (Kind) {
    case MCDR_DataRegion:            OS << "\t.data_region"; break;
    case MCDR_DataRegionJT8:         OS << "\t.data_region jt8"; break;
    case MCDR_DataRegionJT16:        OS << "\t.data_region jt16"; break;
    case MCDR_DataRegionJT32:        OS << "\t.data_region jt32"; break;
    case MCDR_DataRegionEnd:         OS << "\t.end_data_region"; break;
    }
    EmitEOL();
  }
  
  static const char *getVersionMinDirective(MCVersionMinType Type) {
    switch (Type) {
    case MCVM_WatchOSVersionMin: return ".watchos_version_min";
    case MCVM_TvOSVersionMin:    return ".tvos_version_min";
    case MCVM_IOSVersionMin:     return ".ios_version_min";
    case MCVM_OSXVersionMin:     return ".macosx_version_min";
    }
    llvm_unreachable("Invalid MC version min type");
  }
  
  static void EmitSDKVersionSuffix(raw_ostream &OS,
                                   const VersionTuple &SDKVersion) {
    if (SDKVersion.empty())
      return;
    OS << '\t' << "sdk_version " << SDKVersion.getMajor();
    if (auto Minor = SDKVersion.getMinor()) {
      OS << ", " << *Minor;
      if (auto Subminor = SDKVersion.getSubminor()) {
        OS << ", " << *Subminor;
      }
    }
  }
  
  void MCAsmStreamer::EmitVersionMin(MCVersionMinType Type, unsigned Major,
                                     unsigned Minor, unsigned Update,
                                     VersionTuple SDKVersion) {
    OS << '\t' << getVersionMinDirective(Type) << ' ' << Major << ", " << Minor;
    if (Update)
      OS << ", " << Update;
    EmitSDKVersionSuffix(OS, SDKVersion);
    EmitEOL();
  }
  
  static const char *getPlatformName(MachO::PlatformType Type) {
    switch (Type) {
    case MachO::PLATFORM_MACOS:            return "macos";
    case MachO::PLATFORM_IOS:              return "ios";
    case MachO::PLATFORM_TVOS:             return "tvos";
    case MachO::PLATFORM_WATCHOS:          return "watchos";
    case MachO::PLATFORM_BRIDGEOS:         return "bridgeos";
    case MachO::PLATFORM_MACCATALYST:      return "macCatalyst";
    case MachO::PLATFORM_IOSSIMULATOR:     return "iossimulator";
    case MachO::PLATFORM_TVOSSIMULATOR:    return "tvossimulator";
    case MachO::PLATFORM_WATCHOSSIMULATOR: return "watchossimulator";
    }
    llvm_unreachable("Invalid Mach-O platform type");
  }
  
  void MCAsmStreamer::EmitBuildVersion(unsigned Platform, unsigned Major,
                                       unsigned Minor, unsigned Update,
                                       VersionTuple SDKVersion) {
    const char *PlatformName = getPlatformName((MachO::PlatformType)Platform);
    OS << "\t.build_version " << PlatformName << ", " << Major << ", " << Minor;
    if (Update)
      OS << ", " << Update;
    EmitSDKVersionSuffix(OS, SDKVersion);
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitThumbFunc(MCSymbol *Func) {
    // This needs to emit to a temporary string to get properly quoted
    // MCSymbols when they have spaces in them.
    OS << "\t.thumb_func";
    // Only Mach-O hasSubsectionsViaSymbols()
    if (MAI->hasSubsectionsViaSymbols()) {
      OS << '\t';
      Func->print(OS, MAI);
    }
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitAssignment(MCSymbol *Symbol, const MCExpr *Value) {
    // Do not emit a .set on inlined target assignments.
    bool EmitSet = true;
    if (auto *E = dyn_cast<MCTargetExpr>(Value))
      if (E->inlineAssignedExpr())
        EmitSet = false;
    if (EmitSet) {
      OS << ".set ";
      Symbol->print(OS, MAI);
      OS << ", ";
      Value->print(OS, MAI);
  
      EmitEOL();
    }
  
    MCStreamer::EmitAssignment(Symbol, Value);
  }
  
  void MCAsmStreamer::EmitWeakReference(MCSymbol *Alias, const MCSymbol *Symbol) {
    OS << ".weakref ";
    Alias->print(OS, MAI);
    OS << ", ";
    Symbol->print(OS, MAI);
    EmitEOL();
  }
  
  bool MCAsmStreamer::EmitSymbolAttribute(MCSymbol *Symbol,
                                          MCSymbolAttr Attribute) {
    switch (Attribute) {
    case MCSA_Invalid: llvm_unreachable("Invalid symbol attribute");
    case MCSA_ELF_TypeFunction:    /// .type _foo, STT_FUNC  # aka @function
    case MCSA_ELF_TypeIndFunction: /// .type _foo, STT_GNU_IFUNC
    case MCSA_ELF_TypeObject:      /// .type _foo, STT_OBJECT  # aka @object
    case MCSA_ELF_TypeTLS:         /// .type _foo, STT_TLS     # aka @tls_object
    case MCSA_ELF_TypeCommon:      /// .type _foo, STT_COMMON  # aka @common
    case MCSA_ELF_TypeNoType:      /// .type _foo, STT_NOTYPE  # aka @notype
    case MCSA_ELF_TypeGnuUniqueObject:  /// .type _foo, @gnu_unique_object
      if (!MAI->hasDotTypeDotSizeDirective())
        return false; // Symbol attribute not supported
      OS << "\t.type\t";
      Symbol->print(OS, MAI);
      OS << ',' << ((MAI->getCommentString()[0] != '@') ? '@' : '%');
      switch (Attribute) {
      default: return false;
      case MCSA_ELF_TypeFunction:    OS << "function"; break;
      case MCSA_ELF_TypeIndFunction: OS << "gnu_indirect_function"; break;
      case MCSA_ELF_TypeObject:      OS << "object"; break;
      case MCSA_ELF_TypeTLS:         OS << "tls_object"; break;
      case MCSA_ELF_TypeCommon:      OS << "common"; break;
      case MCSA_ELF_TypeNoType:      OS << "notype"; break;
      case MCSA_ELF_TypeGnuUniqueObject: OS << "gnu_unique_object"; break;
      }
      EmitEOL();
      return true;
    case MCSA_Global: // .globl/.global
      OS << MAI->getGlobalDirective();
      break;
    case MCSA_LGlobal:        OS << "\t.lglobl\t";          break;
    case MCSA_Hidden:         OS << "\t.hidden\t";          break;
    case MCSA_IndirectSymbol: OS << "\t.indirect_symbol\t"; break;
    case MCSA_Internal:       OS << "\t.internal\t";        break;
    case MCSA_LazyReference:  OS << "\t.lazy_reference\t";  break;
    case MCSA_Local:          OS << "\t.local\t";           break;
    case MCSA_NoDeadStrip:
      if (!MAI->hasNoDeadStrip())
        return false;
      OS << "\t.no_dead_strip\t";
      break;
    case MCSA_SymbolResolver: OS << "\t.symbol_resolver\t"; break;
    case MCSA_AltEntry:       OS << "\t.alt_entry\t";       break;
    case MCSA_PrivateExtern:
      OS << "\t.private_extern\t";
      break;
    case MCSA_Protected:      OS << "\t.protected\t";       break;
    case MCSA_Reference:      OS << "\t.reference\t";       break;
    case MCSA_Weak:           OS << MAI->getWeakDirective(); break;
    case MCSA_WeakDefinition:
      OS << "\t.weak_definition\t";
      break;
        // .weak_reference
    case MCSA_WeakReference:  OS << MAI->getWeakRefDirective(); break;
    case MCSA_WeakDefAutoPrivate: OS << "\t.weak_def_can_be_hidden\t"; break;
    case MCSA_Cold:
      // Assemblers currently do not support a .cold directive.
      return false;
    }
  
    Symbol->print(OS, MAI);
    EmitEOL();
  
    return true;
  }
  
  void MCAsmStreamer::EmitSymbolDesc(MCSymbol *Symbol, unsigned DescValue) {
    OS << ".desc" << ' ';
    Symbol->print(OS, MAI);
    OS << ',' << DescValue;
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitSyntaxDirective() {
    if (MAI->getAssemblerDialect() == 1) {
      OS << "\t.intel_syntax noprefix";
      EmitEOL();
    }
    // FIXME: Currently emit unprefix'ed registers.
    // The intel_syntax directive has one optional argument
    // with may have a value of prefix or noprefix.
  }
  
  void MCAsmStreamer::BeginCOFFSymbolDef(const MCSymbol *Symbol) {
    OS << "\t.def\t ";
    Symbol->print(OS, MAI);
    OS << ';';
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitCOFFSymbolStorageClass (int StorageClass) {
    OS << "\t.scl\t" << StorageClass << ';';
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitCOFFSymbolType (int Type) {
    OS << "\t.type\t" << Type << ';';
    EmitEOL();
  }
  
  void MCAsmStreamer::EndCOFFSymbolDef() {
    OS << "\t.endef";
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitCOFFSafeSEH(MCSymbol const *Symbol) {
    OS << "\t.safeseh\t";
    Symbol->print(OS, MAI);
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitCOFFSymbolIndex(MCSymbol const *Symbol) {
    OS << "\t.symidx\t";
    Symbol->print(OS, MAI);
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitCOFFSectionIndex(MCSymbol const *Symbol) {
    OS << "\t.secidx\t";
    Symbol->print(OS, MAI);
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitCOFFSecRel32(MCSymbol const *Symbol, uint64_t Offset) {
    OS << "\t.secrel32\t";
    Symbol->print(OS, MAI);
    if (Offset != 0)
      OS << '+' << Offset;
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitCOFFImgRel32(MCSymbol const *Symbol, int64_t Offset) {
    OS << "\t.rva\t";
    Symbol->print(OS, MAI);
    if (Offset > 0)
      OS << '+' << Offset;
    else if (Offset < 0)
      OS << '-' << -Offset;
    EmitEOL();
  }
  
  // We need an XCOFF-specific version of this directive as the AIX syntax
  // requires a QualName argument identifying the csect name and storage mapping
  // class to appear before the alignment if we are specifying it.
  void MCAsmStreamer::EmitXCOFFLocalCommonSymbol(MCSymbol *LabelSym,
                                                 uint64_t Size,
                                                 MCSymbol *CsectSym,
                                                 unsigned ByteAlignment) {
    assert(MAI->getLCOMMDirectiveAlignmentType() == LCOMM::Log2Alignment &&
           "We only support writing log base-2 alignment format with XCOFF.");
    assert(isPowerOf2_32(ByteAlignment) && "Alignment must be a power of 2.");
  
    OS << "\t.lcomm\t";
    LabelSym->print(OS, MAI);
    OS << ',' << Size << ',';
    CsectSym->print(OS, MAI);
    OS << ',' << Log2_32(ByteAlignment);
  
    EmitEOL();
  }
  
  void MCAsmStreamer::emitELFSize(MCSymbol *Symbol, const MCExpr *Value) {
    assert(MAI->hasDotTypeDotSizeDirective());
    OS << "\t.size\t";
    Symbol->print(OS, MAI);
    OS << ", ";
    Value->print(OS, MAI);
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitCommonSymbol(MCSymbol *Symbol, uint64_t Size,
                                       unsigned ByteAlignment) {
    OS << "\t.comm\t";
    Symbol->print(OS, MAI);
    OS << ',' << Size;
  
    if (ByteAlignment != 0) {
      if (MAI->getCOMMDirectiveAlignmentIsInBytes())
        OS << ',' << ByteAlignment;
      else
        OS << ',' << Log2_32(ByteAlignment);
    }
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitLocalCommonSymbol(MCSymbol *Symbol, uint64_t Size,
                                            unsigned ByteAlign) {
    OS << "\t.lcomm\t";
    Symbol->print(OS, MAI);
    OS << ',' << Size;
  
    if (ByteAlign > 1) {
      switch (MAI->getLCOMMDirectiveAlignmentType()) {
      case LCOMM::NoAlignment:
        llvm_unreachable("alignment not supported on .lcomm!");
      case LCOMM::ByteAlignment:
        OS << ',' << ByteAlign;
        break;
      case LCOMM::Log2Alignment:
        assert(isPowerOf2_32(ByteAlign) && "alignment must be a power of 2");
        OS << ',' << Log2_32(ByteAlign);
        break;
      }
    }
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitZerofill(MCSection *Section, MCSymbol *Symbol,
                                   uint64_t Size, unsigned ByteAlignment,
                                   SMLoc Loc) {
    if (Symbol)
      AssignFragment(Symbol, &Section->getDummyFragment());
  
    // Note: a .zerofill directive does not switch sections.
    OS << ".zerofill ";
  
    assert(Section->getVariant() == MCSection::SV_MachO &&
           ".zerofill is a Mach-O specific directive");
    // This is a mach-o specific directive.
  
    const MCSectionMachO *MOSection = ((const MCSectionMachO*)Section);
    OS << MOSection->getSegmentName() << "," << MOSection->getSectionName();
  
    if (Symbol) {
      OS << ',';
      Symbol->print(OS, MAI);
      OS << ',' << Size;
      if (ByteAlignment != 0)
        OS << ',' << Log2_32(ByteAlignment);
    }
    EmitEOL();
  }
  
  // .tbss sym, size, align
  // This depends that the symbol has already been mangled from the original,
  // e.g. _a.
  void MCAsmStreamer::EmitTBSSSymbol(MCSection *Section, MCSymbol *Symbol,
                                     uint64_t Size, unsigned ByteAlignment) {
    AssignFragment(Symbol, &Section->getDummyFragment());
  
    assert(Symbol && "Symbol shouldn't be NULL!");
    // Instead of using the Section we'll just use the shortcut.
  
    assert(Section->getVariant() == MCSection::SV_MachO &&
           ".zerofill is a Mach-O specific directive");
    // This is a mach-o specific directive and section.
  
    OS << ".tbss ";
    Symbol->print(OS, MAI);
    OS << ", " << Size;
  
    // Output align if we have it.  We default to 1 so don't bother printing
    // that.
    if (ByteAlignment > 1) OS << ", " << Log2_32(ByteAlignment);
  
    EmitEOL();
  }
  
  static inline char toOctal(int X) { return (X&7)+'0'; }
  
  static void PrintQuotedString(StringRef Data, raw_ostream &OS) {
    OS << '"';
  
    for (unsigned i = 0, e = Data.size(); i != e; ++i) {
      unsigned char C = Data[i];
      if (C == '"' || C == '\\') {
        OS << '\\' << (char)C;
        continue;
      }
  
      if (isPrint((unsigned char)C)) {
        OS << (char)C;
        continue;
      }
  
      switch (C) {
        case '\b': OS << "\\b"; break;
        case '\f': OS << "\\f"; break;
        case '\n': OS << "\\n"; break;
        case '\r': OS << "\\r"; break;
        case '\t': OS << "\\t"; break;
        default:
          OS << '\\';
          OS << toOctal(C >> 6);
          OS << toOctal(C >> 3);
          OS << toOctal(C >> 0);
          break;
      }
    }
  
    OS << '"';
  }
  
  void MCAsmStreamer::EmitBytes(StringRef Data) {
    assert(getCurrentSectionOnly() &&
           "Cannot emit contents before setting section!");
    if (Data.empty()) return;
  
    // If only single byte is provided or no ascii or asciz directives is
    // supported, emit as vector of 8bits data.
    if (Data.size() == 1 ||
        !(MAI->getAscizDirective() || MAI->getAsciiDirective())) {
      if (MCTargetStreamer *TS = getTargetStreamer()) {
        TS->emitRawBytes(Data);
      } else {
        const char *Directive = MAI->getData8bitsDirective();
        for (const unsigned char C : Data.bytes()) {
          OS << Directive << (unsigned)C;
          EmitEOL();
        }
      }
      return;
    }
  
    // If the data ends with 0 and the target supports .asciz, use it, otherwise
    // use .ascii
    if (MAI->getAscizDirective() && Data.back() == 0) {
      OS << MAI->getAscizDirective();
      Data = Data.substr(0, Data.size()-1);
    } else {
      OS << MAI->getAsciiDirective();
    }
  
    PrintQuotedString(Data, OS);
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitBinaryData(StringRef Data) {
    // This is binary data. Print it in a grid of hex bytes for readability.
    const size_t Cols = 4;
    for (size_t I = 0, EI = alignTo(Data.size(), Cols); I < EI; I += Cols) {
      size_t J = I, EJ = std::min(I + Cols, Data.size());
      assert(EJ > 0);
      OS << MAI->getData8bitsDirective();
      for (; J < EJ - 1; ++J)
        OS << format("0x%02x", uint8_t(Data[J])) << ", ";
      OS << format("0x%02x", uint8_t(Data[J]));
      EmitEOL();
    }
  }
  
  void MCAsmStreamer::EmitIntValue(uint64_t Value, unsigned Size) {
    EmitValue(MCConstantExpr::create(Value, getContext()), Size);
  }
  
  void MCAsmStreamer::EmitIntValueInHex(uint64_t Value, unsigned Size) {
    EmitValue(MCConstantExpr::create(Value, getContext(), true), Size);
  }
  
  void MCAsmStreamer::EmitValueImpl(const MCExpr *Value, unsigned Size,
                                    SMLoc Loc) {
    assert(Size <= 8 && "Invalid size");
    assert(getCurrentSectionOnly() &&
           "Cannot emit contents before setting section!");
    const char *Directive = nullptr;
    switch (Size) {
    default: break;
    case 1: Directive = MAI->getData8bitsDirective();  break;
    case 2: Directive = MAI->getData16bitsDirective(); break;
    case 4: Directive = MAI->getData32bitsDirective(); break;
    case 8: Directive = MAI->getData64bitsDirective(); break;
    }
  
    if (!Directive) {
      int64_t IntValue;
      if (!Value->evaluateAsAbsolute(IntValue))
        report_fatal_error("Don't know how to emit this value.");
  
      // We couldn't handle the requested integer size so we fallback by breaking
      // the request down into several, smaller, integers.
      // Since sizes greater or equal to "Size" are invalid, we use the greatest
      // power of 2 that is less than "Size" as our largest piece of granularity.
      bool IsLittleEndian = MAI->isLittleEndian();
      for (unsigned Emitted = 0; Emitted != Size;) {
        unsigned Remaining = Size - Emitted;
        // The size of our partial emission must be a power of two less than
        // Size.
        unsigned EmissionSize = PowerOf2Floor(std::min(Remaining, Size - 1));
        // Calculate the byte offset of our partial emission taking into account
        // the endianness of the target.
        unsigned ByteOffset =
            IsLittleEndian ? Emitted : (Remaining - EmissionSize);
        uint64_t ValueToEmit = IntValue >> (ByteOffset * 8);
        // We truncate our partial emission to fit within the bounds of the
        // emission domain.  This produces nicer output and silences potential
        // truncation warnings when round tripping through another assembler.
        uint64_t Shift = 64 - EmissionSize * 8;
        assert(Shift < static_cast<uint64_t>(
                           std::numeric_limits<unsigned long long>::digits) &&
               "undefined behavior");
        ValueToEmit &= ~0ULL >> Shift;
        EmitIntValue(ValueToEmit, EmissionSize);
        Emitted += EmissionSize;
      }
      return;
    }
  
    assert(Directive && "Invalid size for machine code value!");
    OS << Directive;
    if (MCTargetStreamer *TS = getTargetStreamer()) {
      TS->emitValue(Value);
    } else {
      Value->print(OS, MAI);
      EmitEOL();
    }
  }
  
  void MCAsmStreamer::EmitULEB128Value(const MCExpr *Value) {
    int64_t IntValue;
    if (Value->evaluateAsAbsolute(IntValue)) {
      EmitULEB128IntValue(IntValue);
      return;
    }
    OS << "\t.uleb128 ";
    Value->print(OS, MAI);
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitSLEB128Value(const MCExpr *Value) {
    int64_t IntValue;
    if (Value->evaluateAsAbsolute(IntValue)) {
      EmitSLEB128IntValue(IntValue);
      return;
    }
    OS << "\t.sleb128 ";
    Value->print(OS, MAI);
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitDTPRel64Value(const MCExpr *Value) {
    assert(MAI->getDTPRel64Directive() != nullptr);
    OS << MAI->getDTPRel64Directive();
    Value->print(OS, MAI);
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitDTPRel32Value(const MCExpr *Value) {
    assert(MAI->getDTPRel32Directive() != nullptr);
    OS << MAI->getDTPRel32Directive();
    Value->print(OS, MAI);
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitTPRel64Value(const MCExpr *Value) {
    assert(MAI->getTPRel64Directive() != nullptr);
    OS << MAI->getTPRel64Directive();
    Value->print(OS, MAI);
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitTPRel32Value(const MCExpr *Value) {
    assert(MAI->getTPRel32Directive() != nullptr);
    OS << MAI->getTPRel32Directive();
    Value->print(OS, MAI);
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitGPRel64Value(const MCExpr *Value) {
    assert(MAI->getGPRel64Directive() != nullptr);
    OS << MAI->getGPRel64Directive();
    Value->print(OS, MAI);
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitGPRel32Value(const MCExpr *Value) {
    assert(MAI->getGPRel32Directive() != nullptr);
    OS << MAI->getGPRel32Directive();
    Value->print(OS, MAI);
    EmitEOL();
  }
  
  void MCAsmStreamer::emitFill(const MCExpr &NumBytes, uint64_t FillValue,
                               SMLoc Loc) {
    int64_t IntNumBytes;
    if (NumBytes.evaluateAsAbsolute(IntNumBytes) && IntNumBytes == 0)
      return;
  
    if (const char *ZeroDirective = MAI->getZeroDirective()) {
      // FIXME: Emit location directives
      OS << ZeroDirective;
      NumBytes.print(OS, MAI);
      if (FillValue != 0)
        OS << ',' << (int)FillValue;
      EmitEOL();
      return;
    }
  
    MCStreamer::emitFill(NumBytes, FillValue);
  }
  
  void MCAsmStreamer::emitFill(const MCExpr &NumValues, int64_t Size,
                               int64_t Expr, SMLoc Loc) {
    // FIXME: Emit location directives
    OS << "\t.fill\t";
    NumValues.print(OS, MAI);
    OS << ", " << Size << ", 0x";
    OS.write_hex(truncateToSize(Expr, 4));
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitValueToAlignment(unsigned ByteAlignment, int64_t Value,
                                           unsigned ValueSize,
                                           unsigned MaxBytesToEmit) {
    if (MAI->useDotAlignForAlignment()) {
      if (!isPowerOf2_32(ByteAlignment))
        report_fatal_error("Only power-of-two alignments are supported "
                           "with .align.");
      OS << "\t.align\t";
      OS << Log2_32(ByteAlignment);
      EmitEOL();
      return;
    }
  
    // Some assemblers don't support non-power of two alignments, so we always
    // emit alignments as a power of two if possible.
    if (isPowerOf2_32(ByteAlignment)) {
      switch (ValueSize) {
      default:
        llvm_unreachable("Invalid size for machine code value!");
      case 1:
        OS << "\t.p2align\t";
        break;
      case 2:
        OS << ".p2alignw ";
        break;
      case 4:
        OS << ".p2alignl ";
        break;
      case 8:
        llvm_unreachable("Unsupported alignment size!");
      }
  
      OS << Log2_32(ByteAlignment);
  
      if (Value || MaxBytesToEmit) {
        OS << ", 0x";
        OS.write_hex(truncateToSize(Value, ValueSize));
  
        if (MaxBytesToEmit)
          OS << ", " << MaxBytesToEmit;
      }
      EmitEOL();
      return;
    }
  
    // Non-power of two alignment.  This is not widely supported by assemblers.
    // FIXME: Parameterize this based on MAI.
    switch (ValueSize) {
    default: llvm_unreachable("Invalid size for machine code value!");
    case 1: OS << ".balign";  break;
    case 2: OS << ".balignw"; break;
    case 4: OS << ".balignl"; break;
    case 8: llvm_unreachable("Unsupported alignment size!");
    }
  
    OS << ' ' << ByteAlignment;
    OS << ", " << truncateToSize(Value, ValueSize);
    if (MaxBytesToEmit)
      OS << ", " << MaxBytesToEmit;
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitCodeAlignment(unsigned ByteAlignment,
                                        unsigned MaxBytesToEmit) {
    // Emit with a text fill value.
    EmitValueToAlignment(ByteAlignment, MAI->getTextAlignFillValue(),
                         1, MaxBytesToEmit);
  }
  
  void MCAsmStreamer::emitValueToOffset(const MCExpr *Offset,
                                        unsigned char Value,
                                        SMLoc Loc) {
    // FIXME: Verify that Offset is associated with the current section.
    OS << ".org ";
    Offset->print(OS, MAI);
    OS << ", " << (unsigned)Value;
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitFileDirective(StringRef Filename) {
    assert(MAI->hasSingleParameterDotFile());
    OS << "\t.file\t";
    PrintQuotedString(Filename, OS);
    EmitEOL();
  }
  
  static void printDwarfFileDirective(unsigned FileNo, StringRef Directory,
                                      StringRef Filename,
                                      Optional<MD5::MD5Result> Checksum,
                                      Optional<StringRef> Source,
                                      bool UseDwarfDirectory,
                                      raw_svector_ostream &OS) {
    SmallString<128> FullPathName;
  
    if (!UseDwarfDirectory && !Directory.empty()) {
      if (sys::path::is_absolute(Filename))
        Directory = "";
      else {
        FullPathName = Directory;
        sys::path::append(FullPathName, Filename);
        Directory = "";
        Filename = FullPathName;
      }
    }
  
    OS << "\t.file\t" << FileNo << ' ';
    if (!Directory.empty()) {
      PrintQuotedString(Directory, OS);
      OS << ' ';
    }
    PrintQuotedString(Filename, OS);
    if (Checksum)
      OS << " md5 0x" << Checksum->digest();
    if (Source) {
      OS << " source ";
      PrintQuotedString(*Source, OS);
    }
  }
  
  Expected<unsigned> MCAsmStreamer::tryEmitDwarfFileDirective(
      unsigned FileNo, StringRef Directory, StringRef Filename,
      Optional<MD5::MD5Result> Checksum, Optional<StringRef> Source, unsigned CUID) {
    assert(CUID == 0 && "multiple CUs not supported by MCAsmStreamer");
  
    MCDwarfLineTable &Table = getContext().getMCDwarfLineTable(CUID);
    unsigned NumFiles = Table.getMCDwarfFiles().size();
    Expected<unsigned> FileNoOrErr =
        Table.tryGetFile(Directory, Filename, Checksum, Source,
                         getContext().getDwarfVersion(), FileNo);
    if (!FileNoOrErr)
      return FileNoOrErr.takeError();
    FileNo = FileNoOrErr.get();
    if (NumFiles == Table.getMCDwarfFiles().size())
      return FileNo;
  
    SmallString<128> Str;
    raw_svector_ostream OS1(Str);
    printDwarfFileDirective(FileNo, Directory, Filename, Checksum, Source,
                            UseDwarfDirectory, OS1);
  
    if (MCTargetStreamer *TS = getTargetStreamer())
      TS->emitDwarfFileDirective(OS1.str());
    else
      EmitRawText(OS1.str());
  
    return FileNo;
  }
  
  void MCAsmStreamer::emitDwarfFile0Directive(StringRef Directory,
                                              StringRef Filename,
                                              Optional<MD5::MD5Result> Checksum,
                                              Optional<StringRef> Source,
                                              unsigned CUID) {
    assert(CUID == 0);
    // .file 0 is new for DWARF v5.
    if (getContext().getDwarfVersion() < 5)
      return;
    // Inform MCDwarf about the root file.
    getContext().setMCLineTableRootFile(CUID, Directory, Filename, Checksum,
                                        Source);
  
    SmallString<128> Str;
    raw_svector_ostream OS1(Str);
    printDwarfFileDirective(0, Directory, Filename, Checksum, Source,
                            UseDwarfDirectory, OS1);
  
    if (MCTargetStreamer *TS = getTargetStreamer())
      TS->emitDwarfFileDirective(OS1.str());
    else
      EmitRawText(OS1.str());
  }
  
  void MCAsmStreamer::EmitDwarfLocDirective(unsigned FileNo, unsigned Line,
                                            unsigned Column, unsigned Flags,
                                            unsigned Isa,
                                            unsigned Discriminator,
                                            StringRef FileName) {
    OS << "\t.loc\t" << FileNo << " " << Line << " " << Column;
    if (MAI->supportsExtendedDwarfLocDirective()) {
      if (Flags & DWARF2_FLAG_BASIC_BLOCK)
        OS << " basic_block";
      if (Flags & DWARF2_FLAG_PROLOGUE_END)
        OS << " prologue_end";
      if (Flags & DWARF2_FLAG_EPILOGUE_BEGIN)
        OS << " epilogue_begin";
  
      unsigned OldFlags = getContext().getCurrentDwarfLoc().getFlags();
      if ((Flags & DWARF2_FLAG_IS_STMT) != (OldFlags & DWARF2_FLAG_IS_STMT)) {
        OS << " is_stmt ";
  
        if (Flags & DWARF2_FLAG_IS_STMT)
          OS << "1";
        else
          OS << "0";
      }
  
      if (Isa)
        OS << " isa " << Isa;
      if (Discriminator)
        OS << " discriminator " << Discriminator;
    }
  
    if (IsVerboseAsm) {
      OS.PadToColumn(MAI->getCommentColumn());
      OS << MAI->getCommentString() << ' ' << FileName << ':'
         << Line << ':' << Column;
    }
    EmitEOL();
    this->MCStreamer::EmitDwarfLocDirective(FileNo, Line, Column, Flags,
                                            Isa, Discriminator, FileName);
  }
  
  MCSymbol *MCAsmStreamer::getDwarfLineTableSymbol(unsigned CUID) {
    // Always use the zeroth line table, since asm syntax only supports one line
    // table for now.
    return MCStreamer::getDwarfLineTableSymbol(0);
  }
  
  bool MCAsmStreamer::EmitCVFileDirective(unsigned FileNo, StringRef Filename,
                                          ArrayRef<uint8_t> Checksum,
                                          unsigned ChecksumKind) {
    if (!getContext().getCVContext().addFile(*this, FileNo, Filename, Checksum,
                                             ChecksumKind))
      return false;
  
    OS << "\t.cv_file\t" << FileNo << ' ';
    PrintQuotedString(Filename, OS);
  
    if (!ChecksumKind) {
      EmitEOL();
      return true;
    }
  
    OS << ' ';
    PrintQuotedString(toHex(Checksum), OS);
    OS << ' ' << ChecksumKind;
  
    EmitEOL();
    return true;
  }
  
  bool MCAsmStreamer::EmitCVFuncIdDirective(unsigned FuncId) {
    OS << "\t.cv_func_id " << FuncId << '\n';
    return MCStreamer::EmitCVFuncIdDirective(FuncId);
  }
  
  bool MCAsmStreamer::EmitCVInlineSiteIdDirective(unsigned FunctionId,
                                                  unsigned IAFunc,
                                                  unsigned IAFile,
                                                  unsigned IALine, unsigned IACol,
                                                  SMLoc Loc) {
    OS << "\t.cv_inline_site_id " << FunctionId << " within " << IAFunc
       << " inlined_at " << IAFile << ' ' << IALine << ' ' << IACol << '\n';
    return MCStreamer::EmitCVInlineSiteIdDirective(FunctionId, IAFunc, IAFile,
                                                   IALine, IACol, Loc);
  }
  
  void MCAsmStreamer::EmitCVLocDirective(unsigned FunctionId, unsigned FileNo,
                                         unsigned Line, unsigned Column,
                                         bool PrologueEnd, bool IsStmt,
                                         StringRef FileName, SMLoc Loc) {
    // Validate the directive.
    if (!checkCVLocSection(FunctionId, FileNo, Loc))
      return;
  
    OS << "\t.cv_loc\t" << FunctionId << " " << FileNo << " " << Line << " "
       << Column;
    if (PrologueEnd)
      OS << " prologue_end";
  
    if (IsStmt)
      OS << " is_stmt 1";
  
    if (IsVerboseAsm) {
      OS.PadToColumn(MAI->getCommentColumn());
      OS << MAI->getCommentString() << ' ' << FileName << ':' << Line << ':'
         << Column;
    }
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitCVLinetableDirective(unsigned FunctionId,
                                               const MCSymbol *FnStart,
                                               const MCSymbol *FnEnd) {
    OS << "\t.cv_linetable\t" << FunctionId << ", ";
    FnStart->print(OS, MAI);
    OS << ", ";
    FnEnd->print(OS, MAI);
    EmitEOL();
    this->MCStreamer::EmitCVLinetableDirective(FunctionId, FnStart, FnEnd);
  }
  
  void MCAsmStreamer::EmitCVInlineLinetableDirective(unsigned PrimaryFunctionId,
                                                     unsigned SourceFileId,
                                                     unsigned SourceLineNum,
                                                     const MCSymbol *FnStartSym,
                                                     const MCSymbol *FnEndSym) {
    OS << "\t.cv_inline_linetable\t" << PrimaryFunctionId << ' ' << SourceFileId
       << ' ' << SourceLineNum << ' ';
    FnStartSym->print(OS, MAI);
    OS << ' ';
    FnEndSym->print(OS, MAI);
    EmitEOL();
    this->MCStreamer::EmitCVInlineLinetableDirective(
        PrimaryFunctionId, SourceFileId, SourceLineNum, FnStartSym, FnEndSym);
  }
  
  void MCAsmStreamer::PrintCVDefRangePrefix(
      ArrayRef<std::pair<const MCSymbol *, const MCSymbol *>> Ranges) {
    OS << "\t.cv_def_range\t";
    for (std::pair<const MCSymbol *, const MCSymbol *> Range : Ranges) {
      OS << ' ';
      Range.first->print(OS, MAI);
      OS << ' ';
      Range.second->print(OS, MAI);
    }
  }
  
  void MCAsmStreamer::EmitCVDefRangeDirective(
      ArrayRef<std::pair<const MCSymbol *, const MCSymbol *>> Ranges,
      codeview::DefRangeRegisterRelHeader DRHdr) {
    PrintCVDefRangePrefix(Ranges);
    OS << ", reg_rel, ";
    OS << DRHdr.Register << ", " << DRHdr.Flags << ", "
       << DRHdr.BasePointerOffset;
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitCVDefRangeDirective(
      ArrayRef<std::pair<const MCSymbol *, const MCSymbol *>> Ranges,
      codeview::DefRangeSubfieldRegisterHeader DRHdr) {
    PrintCVDefRangePrefix(Ranges);
    OS << ", subfield_reg, ";
    OS << DRHdr.Register << ", " << DRHdr.OffsetInParent;
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitCVDefRangeDirective(
      ArrayRef<std::pair<const MCSymbol *, const MCSymbol *>> Ranges,
      codeview::DefRangeRegisterHeader DRHdr) {
    PrintCVDefRangePrefix(Ranges);
    OS << ", reg, ";
    OS << DRHdr.Register;
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitCVDefRangeDirective(
      ArrayRef<std::pair<const MCSymbol *, const MCSymbol *>> Ranges,
      codeview::DefRangeFramePointerRelHeader DRHdr) {
    PrintCVDefRangePrefix(Ranges);
    OS << ", frame_ptr_rel, ";
    OS << DRHdr.Offset;
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitCVStringTableDirective() {
    OS << "\t.cv_stringtable";
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitCVFileChecksumsDirective() {
    OS << "\t.cv_filechecksums";
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitCVFileChecksumOffsetDirective(unsigned FileNo) {
    OS << "\t.cv_filechecksumoffset\t" << FileNo;
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitCVFPOData(const MCSymbol *ProcSym, SMLoc L) {
    OS << "\t.cv_fpo_data\t";
    ProcSym->print(OS, MAI);
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitIdent(StringRef IdentString) {
    assert(MAI->hasIdentDirective() && ".ident directive not supported");
    OS << "\t.ident\t";
    PrintQuotedString(IdentString, OS);
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitCFISections(bool EH, bool Debug) {
    MCStreamer::EmitCFISections(EH, Debug);
    OS << "\t.cfi_sections ";
    if (EH) {
      OS << ".eh_frame";
      if (Debug)
        OS << ", .debug_frame";
    } else if (Debug) {
      OS << ".debug_frame";
    }
  
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitCFIStartProcImpl(MCDwarfFrameInfo &Frame) {
    OS << "\t.cfi_startproc";
    if (Frame.IsSimple)
      OS << " simple";
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitCFIEndProcImpl(MCDwarfFrameInfo &Frame) {
    MCStreamer::EmitCFIEndProcImpl(Frame);
    OS << "\t.cfi_endproc";
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitRegisterName(int64_t Register) {
    if (!MAI->useDwarfRegNumForCFI()) {
      // User .cfi_* directives can use arbitrary DWARF register numbers, not
      // just ones that map to LLVM register numbers and have known names.
      // Fall back to using the original number directly if no name is known.
      const MCRegisterInfo *MRI = getContext().getRegisterInfo();
      if (Optional<unsigned> LLVMRegister = MRI->getLLVMRegNum(Register, true)) {
        InstPrinter->printRegName(OS, *LLVMRegister);
        return;
      }
    }
    OS << Register;
  }
  
  void MCAsmStreamer::EmitCFIDefCfa(int64_t Register, int64_t Offset) {
    MCStreamer::EmitCFIDefCfa(Register, Offset);
    OS << "\t.cfi_def_cfa ";
    EmitRegisterName(Register);
    OS << ", " << Offset;
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitCFIDefCfaOffset(int64_t Offset) {
    MCStreamer::EmitCFIDefCfaOffset(Offset);
    OS << "\t.cfi_def_cfa_offset " << Offset;
    EmitEOL();
  }
  
  static void PrintCFIEscape(llvm::formatted_raw_ostream &OS, StringRef Values) {
    OS << "\t.cfi_escape ";
    if (!Values.empty()) {
      size_t e = Values.size() - 1;
      for (size_t i = 0; i < e; ++i)
        OS << format("0x%02x", uint8_t(Values[i])) << ", ";
      OS << format("0x%02x", uint8_t(Values[e]));
    }
  }
  
  void MCAsmStreamer::EmitCFIEscape(StringRef Values) {
    MCStreamer::EmitCFIEscape(Values);
    PrintCFIEscape(OS, Values);
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitCFIGnuArgsSize(int64_t Size) {
    MCStreamer::EmitCFIGnuArgsSize(Size);
  
    uint8_t Buffer[16] = { dwarf::DW_CFA_GNU_args_size };
    unsigned Len = encodeULEB128(Size, Buffer + 1) + 1;
  
    PrintCFIEscape(OS, StringRef((const char *)&Buffer[0], Len));
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitCFIDefCfaRegister(int64_t Register) {
    MCStreamer::EmitCFIDefCfaRegister(Register);
    OS << "\t.cfi_def_cfa_register ";
    EmitRegisterName(Register);
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitCFIOffset(int64_t Register, int64_t Offset) {
    this->MCStreamer::EmitCFIOffset(Register, Offset);
    OS << "\t.cfi_offset ";
    EmitRegisterName(Register);
    OS << ", " << Offset;
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitCFIPersonality(const MCSymbol *Sym,
                                         unsigned Encoding) {
    MCStreamer::EmitCFIPersonality(Sym, Encoding);
    OS << "\t.cfi_personality " << Encoding << ", ";
    Sym->print(OS, MAI);
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitCFILsda(const MCSymbol *Sym, unsigned Encoding) {
    MCStreamer::EmitCFILsda(Sym, Encoding);
    OS << "\t.cfi_lsda " << Encoding << ", ";
    Sym->print(OS, MAI);
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitCFIRememberState() {
    MCStreamer::EmitCFIRememberState();
    OS << "\t.cfi_remember_state";
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitCFIRestoreState() {
    MCStreamer::EmitCFIRestoreState();
    OS << "\t.cfi_restore_state";
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitCFIRestore(int64_t Register) {
    MCStreamer::EmitCFIRestore(Register);
    OS << "\t.cfi_restore ";
    EmitRegisterName(Register);
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitCFISameValue(int64_t Register) {
    MCStreamer::EmitCFISameValue(Register);
    OS << "\t.cfi_same_value ";
    EmitRegisterName(Register);
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitCFIRelOffset(int64_t Register, int64_t Offset) {
    MCStreamer::EmitCFIRelOffset(Register, Offset);
    OS << "\t.cfi_rel_offset ";
    EmitRegisterName(Register);
    OS << ", " << Offset;
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitCFIAdjustCfaOffset(int64_t Adjustment) {
    MCStreamer::EmitCFIAdjustCfaOffset(Adjustment);
    OS << "\t.cfi_adjust_cfa_offset " << Adjustment;
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitCFISignalFrame() {
    MCStreamer::EmitCFISignalFrame();
    OS << "\t.cfi_signal_frame";
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitCFIUndefined(int64_t Register) {
    MCStreamer::EmitCFIUndefined(Register);
    OS << "\t.cfi_undefined " << Register;
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitCFIRegister(int64_t Register1, int64_t Register2) {
    MCStreamer::EmitCFIRegister(Register1, Register2);
    OS << "\t.cfi_register " << Register1 << ", " << Register2;
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitCFIWindowSave() {
    MCStreamer::EmitCFIWindowSave();
    OS << "\t.cfi_window_save";
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitCFINegateRAState() {
    MCStreamer::EmitCFINegateRAState();
    OS << "\t.cfi_negate_ra_state";
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitCFIReturnColumn(int64_t Register) {
    MCStreamer::EmitCFIReturnColumn(Register);
    OS << "\t.cfi_return_column " << Register;
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitCFIBKeyFrame() {
    MCStreamer::EmitCFIBKeyFrame();
    OS << "\t.cfi_b_key_frame";
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitWinCFIStartProc(const MCSymbol *Symbol, SMLoc Loc) {
    MCStreamer::EmitWinCFIStartProc(Symbol, Loc);
  
    OS << ".seh_proc ";
    Symbol->print(OS, MAI);
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitWinCFIEndProc(SMLoc Loc) {
    MCStreamer::EmitWinCFIEndProc(Loc);
  
    OS << "\t.seh_endproc";
    EmitEOL();
  }
  
  // TODO: Implement
  void MCAsmStreamer::EmitWinCFIFuncletOrFuncEnd(SMLoc Loc) {
  }
  
  void MCAsmStreamer::EmitWinCFIStartChained(SMLoc Loc) {
    MCStreamer::EmitWinCFIStartChained(Loc);
  
    OS << "\t.seh_startchained";
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitWinCFIEndChained(SMLoc Loc) {
    MCStreamer::EmitWinCFIEndChained(Loc);
  
    OS << "\t.seh_endchained";
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitWinEHHandler(const MCSymbol *Sym, bool Unwind,
                                       bool Except, SMLoc Loc) {
    MCStreamer::EmitWinEHHandler(Sym, Unwind, Except, Loc);
  
    OS << "\t.seh_handler ";
    Sym->print(OS, MAI);
    if (Unwind)
      OS << ", @unwind";
    if (Except)
      OS << ", @except";
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitWinEHHandlerData(SMLoc Loc) {
    MCStreamer::EmitWinEHHandlerData(Loc);
  
    // Switch sections. Don't call SwitchSection directly, because that will
    // cause the section switch to be visible in the emitted assembly.
    // We only do this so the section switch that terminates the handler
    // data block is visible.
    WinEH::FrameInfo *CurFrame = getCurrentWinFrameInfo();
  
    // Do nothing if no frame is open. MCStreamer should've already reported an
    // error.
    if (!CurFrame)
      return;
  
    MCSection *TextSec = &CurFrame->Function->getSection();
    MCSection *XData = getAssociatedXDataSection(TextSec);
    SwitchSectionNoChange(XData);
  
    OS << "\t.seh_handlerdata";
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitWinCFIPushReg(MCRegister Register, SMLoc Loc) {
    MCStreamer::EmitWinCFIPushReg(Register, Loc);
  
    OS << "\t.seh_pushreg ";
    InstPrinter->printRegName(OS, Register);
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitWinCFISetFrame(MCRegister Register, unsigned Offset,
                                         SMLoc Loc) {
    MCStreamer::EmitWinCFISetFrame(Register, Offset, Loc);
  
    OS << "\t.seh_setframe ";
    InstPrinter->printRegName(OS, Register);
    OS << ", " << Offset;
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitWinCFIAllocStack(unsigned Size, SMLoc Loc) {
    MCStreamer::EmitWinCFIAllocStack(Size, Loc);
  
    OS << "\t.seh_stackalloc " << Size;
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitWinCFISaveReg(MCRegister Register, unsigned Offset,
                                        SMLoc Loc) {
    MCStreamer::EmitWinCFISaveReg(Register, Offset, Loc);
  
    OS << "\t.seh_savereg ";
    InstPrinter->printRegName(OS, Register);
    OS << ", " << Offset;
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitWinCFISaveXMM(MCRegister Register, unsigned Offset,
                                        SMLoc Loc) {
    MCStreamer::EmitWinCFISaveXMM(Register, Offset, Loc);
  
    OS << "\t.seh_savexmm ";
    InstPrinter->printRegName(OS, Register);
    OS << ", " << Offset;
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitWinCFIPushFrame(bool Code, SMLoc Loc) {
    MCStreamer::EmitWinCFIPushFrame(Code, Loc);
  
    OS << "\t.seh_pushframe";
    if (Code)
      OS << " @code";
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitWinCFIEndProlog(SMLoc Loc) {
    MCStreamer::EmitWinCFIEndProlog(Loc);
  
    OS << "\t.seh_endprologue";
    EmitEOL();
  }
  
  void MCAsmStreamer::emitCGProfileEntry(const MCSymbolRefExpr *From,
                                         const MCSymbolRefExpr *To,
                                         uint64_t Count) {
    OS << "\t.cg_profile ";
    From->getSymbol().print(OS, MAI);
    OS << ", ";
    To->getSymbol().print(OS, MAI);
    OS << ", " << Count;
    EmitEOL();
  }
  
  void MCAsmStreamer::AddEncodingComment(const MCInst &Inst,
                                         const MCSubtargetInfo &STI) {
    raw_ostream &OS = GetCommentOS();
    SmallString<256> Code;
    SmallVector<MCFixup, 4> Fixups;
    raw_svector_ostream VecOS(Code);
  
    // If we have no code emitter, don't emit code.
    if (!getAssembler().getEmitterPtr())
      return;
  
    getAssembler().getEmitter().encodeInstruction(Inst, VecOS, Fixups, STI);
  
    // If we are showing fixups, create symbolic markers in the encoded
    // representation. We do this by making a per-bit map to the fixup item index,
    // then trying to display it as nicely as possible.
    SmallVector<uint8_t, 64> FixupMap;
    FixupMap.resize(Code.size() * 8);
    for (unsigned i = 0, e = Code.size() * 8; i != e; ++i)
      FixupMap[i] = 0;
  
    for (unsigned i = 0, e = Fixups.size(); i != e; ++i) {
      MCFixup &F = Fixups[i];
      const MCFixupKindInfo &Info =
          getAssembler().getBackend().getFixupKindInfo(F.getKind());
      for (unsigned j = 0; j != Info.TargetSize; ++j) {
        unsigned Index = F.getOffset() * 8 + Info.TargetOffset + j;
        assert(Index < Code.size() * 8 && "Invalid offset in fixup!");
        FixupMap[Index] = 1 + i;
      }
    }
  
    // FIXME: Note the fixup comments for Thumb2 are completely bogus since the
    // high order halfword of a 32-bit Thumb2 instruction is emitted first.
    OS << "encoding: [";
    for (unsigned i = 0, e = Code.size(); i != e; ++i) {
      if (i)
        OS << ',';
  
      // See if all bits are the same map entry.
      uint8_t MapEntry = FixupMap[i * 8 + 0];
      for (unsigned j = 1; j != 8; ++j) {
        if (FixupMap[i * 8 + j] == MapEntry)
          continue;
  
        MapEntry = uint8_t(~0U);
        break;
      }
  
      if (MapEntry != uint8_t(~0U)) {
        if (MapEntry == 0) {
          OS << format("0x%02x", uint8_t(Code[i]));
        } else {
          if (Code[i]) {
            // FIXME: Some of the 8 bits require fix up.
            OS << format("0x%02x", uint8_t(Code[i])) << '\''
               << char('A' + MapEntry - 1) << '\'';
          } else
            OS << char('A' + MapEntry - 1);
        }
      } else {
        // Otherwise, write out in binary.
        OS << "0b";
        for (unsigned j = 8; j--;) {
          unsigned Bit = (Code[i] >> j) & 1;
  
          unsigned FixupBit;
          if (MAI->isLittleEndian())
            FixupBit = i * 8 + j;
          else
            FixupBit = i * 8 + (7-j);
  
          if (uint8_t MapEntry = FixupMap[FixupBit]) {
            assert(Bit == 0 && "Encoder wrote into fixed up bit!");
            OS << char('A' + MapEntry - 1);
          } else
            OS << Bit;
        }
      }
    }
    OS << "]\n";
  
    for (unsigned i = 0, e = Fixups.size(); i != e; ++i) {
      MCFixup &F = Fixups[i];
      const MCFixupKindInfo &Info =
          getAssembler().getBackend().getFixupKindInfo(F.getKind());
      OS << "  fixup " << char('A' + i) << " - " << "offset: " << F.getOffset()
         << ", value: " << *F.getValue() << ", kind: " << Info.Name << "\n";
    }
  }
  
  void MCAsmStreamer::EmitInstruction(const MCInst &Inst,
                                      const MCSubtargetInfo &STI) {
    assert(getCurrentSectionOnly() &&
           "Cannot emit contents before setting section!");
  
    // Show the encoding in a comment if we have a code emitter.
    AddEncodingComment(Inst, STI);
  
    // Show the MCInst if enabled.
    if (ShowInst) {
      Inst.dump_pretty(GetCommentOS(), InstPrinter.get(), "\n ");
      GetCommentOS() << "\n";
    }
  
    if(getTargetStreamer())
      getTargetStreamer()->prettyPrintAsm(*InstPrinter, 0, Inst, STI, OS);
    else
      InstPrinter->printInst(&Inst, 0, "", STI, OS);
  
    StringRef Comments = CommentToEmit;
    if (Comments.size() && Comments.back() != '\n')
      GetCommentOS() << "\n";
  
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitBundleAlignMode(unsigned AlignPow2) {
    OS << "\t.bundle_align_mode " << AlignPow2;
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitBundleLock(bool AlignToEnd) {
    OS << "\t.bundle_lock";
    if (AlignToEnd)
      OS << " align_to_end";
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitBundleUnlock() {
    OS << "\t.bundle_unlock";
    EmitEOL();
  }
  
  bool MCAsmStreamer::EmitRelocDirective(const MCExpr &Offset, StringRef Name,
                                         const MCExpr *Expr, SMLoc,
                                         const MCSubtargetInfo &STI) {
    OS << "\t.reloc ";
    Offset.print(OS, MAI);
    OS << ", " << Name;
    if (Expr) {
      OS << ", ";
      Expr->print(OS, MAI);
    }
    EmitEOL();
    return false;
  }
  
  void MCAsmStreamer::EmitAddrsig() {
    OS << "\t.addrsig";
    EmitEOL();
  }
  
  void MCAsmStreamer::EmitAddrsigSym(const MCSymbol *Sym) {
    OS << "\t.addrsig_sym ";
    Sym->print(OS, MAI);
    EmitEOL();
  }
  
  /// EmitRawText - If this file is backed by an assembly streamer, this dumps
  /// the specified string in the output .s file.  This capability is
  /// indicated by the hasRawTextSupport() predicate.
  void MCAsmStreamer::EmitRawTextImpl(StringRef String) {
    if (!String.empty() && String.back() == '\n')
      String = String.substr(0, String.size()-1);
    OS << String;
    EmitEOL();
  }
  
  void MCAsmStreamer::FinishImpl() {
    // If we are generating dwarf for assembly source files dump out the sections.
    if (getContext().getGenDwarfForAssembly())
      MCGenDwarfInfo::Emit(this);
  
    // Emit the label for the line table, if requested - since the rest of the
    // line table will be defined by .loc/.file directives, and not emitted
    // directly, the label is the only work required here.
    const auto &Tables = getContext().getMCDwarfLineTables();
    if (!Tables.empty()) {
      assert(Tables.size() == 1 && "asm output only supports one line table");
      if (auto *Label = Tables.begin()->second.getLabel()) {
        SwitchSection(getContext().getObjectFileInfo()->getDwarfLineSection());
        EmitLabel(Label);
      }
    }
  }
  
  MCStreamer *llvm::createAsmStreamer(MCContext &Context,
                                      std::unique_ptr<formatted_raw_ostream> OS,
                                      bool isVerboseAsm, bool useDwarfDirectory,
                                      MCInstPrinter *IP,
                                      std::unique_ptr<MCCodeEmitter> &&CE,
                                      std::unique_ptr<MCAsmBackend> &&MAB,
                                      bool ShowInst) {
    return new MCAsmStreamer(Context, std::move(OS), isVerboseAsm,
                             useDwarfDirectory, IP, std::move(CE), std::move(MAB),
                             ShowInst);
  }
  