[debug-info] [NFC] add is-a(isa<>) support for MCStreamer

[shchenz]

Summary

This is a simple refactor. In some cases, we need to check if a MCStreamer pointer is MCAsmStreamer or MCObjectStreamer, so we can implement some different behaviour in assembly mode and object mode.

For example, we are going to support dwarf for XCOFF. XCOFF assembler will fill the .debug_line or .debug_info length into the final object file, so in assembly mode, compiler should not emit .debug_line or .debug_info length into the section header, but in object mode, we still need that length to make other tools happy.

[nemanjai]

Added Eric as the owner of debug info.

[shchenz]

In D94668#2497861, @nemanjai wrote:

Added Eric as the owner of debug info.

thanks for your kindly help. @nemanjai

[echristo]

I'm not quite sure I understand. What's the issue between xcoff and emission here? Does it not support subtraction? It's been a while and I can't recall.

-eric

[shchenz]

In D94668#2500530, @echristo wrote:

I'm not quite sure I understand. What's the issue between xcoff and emission here? Does it not support subtraction? It's been a while and I can't recall.

-eric

Hi Eric,
Thanks for your review. I made some background for this patch in https://reviews.llvm.org/D94670.

On AIX, the assembler does not need the assembly file contains the dwarf sections length info in the dwarf section header(if the dwarf section has header.) Instead, the assembler will insert the calculated length into dwarf sections header of the final object according to DWARF type. Namely AIX assembler will insert 4 bytes in each section header for DWARF32 and 12 bytes for DWARF64.

So the issue is for assembly mode, we don't need the dwarf section length in the dwarf section header as assembler will insert this info. But for object mode, we still need the dwarf section length as other tool like linker will need this.

Currently the dwarf section length is emitted by base class MCStreamer, so I need to check if MCStreamer is MCAsmStreamer or not for XCOFF. If it is MCAsmStreamer, we don't emit length info; if it is MCObjectStreamer, we need to emit the length info.

XCOFF may also need to emit .debug_line info according to Streamer type. AIX assembler does not support .loc, .file directive, so we have to write another method to emit .debug_line content for MCAsmStreamer.

Do we have other ways for this kind of requirement?

[ikudrin]

Is it possible to encapsulate the target-specific logic into some derived classes from MCStreamer so that MCStreamer itself and DWARF emitter classes work through a common interface and have no target-specific adjustments?

[shchenz]

In D94668#2500791, @ikudrin wrote:

Is it possible to encapsulate the target-specific logic into some derived classes from MCStreamer so that MCStreamer itself and DWARF emitter classes work through a common interface and have no target-specific adjustments?

Thanks for your comments @ikudrin I know what you mean. But for the use cases in D95518, we need to differentiate MCAsmStreamer and MCObjectStreamer in many classes that contain an MCStreamer pointer. I am not sure if a common interface in MCStreamer class can be easily and logically found. For example the uses in file lib/CodeGen/AsmPrinter/DwarfCompileUnit.cpp in D95518. Could you please help to look at the consumer patch D95518 and tell me what you think? Thanks again.

[ikudrin]

This comment was removed by ikudrin.

[shchenz]

Gentle ping...

We still need this patch for D95518 for lib/Target/PowerPC/PPCAsmPrinter.cpp file. We need to emit the end symbol for asmstreamer to tell where is the end of the text section.

[MaskRay]

In PPCAsmPrinter.cpp, if you use getStreamerKind() == MCStreamer::StreamerKindAs, then the code motion into MCAsmStreamer.h will not be needed. The classof functions are unused, too.

[MaskRay]

isa in the subject confused me - I thought it was "An unsigned integer whose value encodes the applicable instruction set architecture for the current instruction" in the line number information, given the debug info context.

It is actually https://llvm.org/docs/HowToSetUpLLVMStyleRTTI.html

[shchenz]

Thanks for review @MaskRay

In D94668#2553332, @MaskRay wrote:

isa in the subject confused me - I thought it was "An unsigned integer whose value encodes the applicable instruction set architecture for the current instruction" in the line number information, given the debug info context.

It is actually https://llvm.org/docs/HowToSetUpLLVMStyleRTTI.html

Right, the isa in the subject is for is-a used in llvm style RTTI.

In D94668#2553331, @MaskRay wrote:

In PPCAsmPrinter.cpp, if you use getStreamerKind() == MCStreamer::StreamerKindAs, then the code motion into MCAsmStreamer.h will not be needed. The classof functions are unused, too.

I am not very clear about this comment, I think isa<MCAsmStreamer> is more common usage. We don't need to explicitly call getStreamerKind() to do a type check. For example, when we check an AllocaInst, we won't do this like I->getOpcode() == Instruction::Alloca, we do it like isa<AllocaInst>(I).

[MaskRay]

In D94668#2553371, @shchenz wrote:

Thanks for review @MaskRay

In D94668#2553332, @MaskRay wrote:

isa in the subject confused me - I thought it was "An unsigned integer whose value encodes the applicable instruction set architecture for the current instruction" in the line number information, given the debug info context.

It is actually https://llvm.org/docs/HowToSetUpLLVMStyleRTTI.html

Right, the isa in the subject is for is-a used in llvm style RTTI.

In D94668#2553331, @MaskRay wrote:

In PPCAsmPrinter.cpp, if you use getStreamerKind() == MCStreamer::StreamerKindAs, then the code motion into MCAsmStreamer.h will not be needed. The classof functions are unused, too.

I am not very clear about this comment, I think isa<MCAsmStreamer> is more common usage. We don't need to explicitly call getStreamerKind() to do a type check. For example, when we check an AllocaInst, we won't do this like I->getOpcode() == Instruction::Alloca, we do it like isa<AllocaInst>(I).

Both ->isXXXX and isa<...> are common. isa<MCAsmStreamer> requires you to move the code to a separate header. I don't think it justifies the code motion.

[ikudrin]

In D94668#2553258, @shchenz wrote:

Gentle ping...

We still need this patch for D95518 for lib/Target/PowerPC/PPCAsmPrinter.cpp file. We need to emit the end symbol for asmstreamer to tell where is the end of the text section.

That is yet another case when the patch tries to break the abstraction. It would be better to rewrite it in a more general way that avoids casting. Thus, this patch will not be needed.

[shchenz]

In D94668#2553382, @ikudrin wrote:

In D94668#2553258, @shchenz wrote:

Gentle ping...

We still need this patch for D95518 for lib/Target/PowerPC/PPCAsmPrinter.cpp file. We need to emit the end symbol for asmstreamer to tell where is the end of the text section.

That is yet another case when the patch tries to break the abstraction. It would be better to rewrite it in a more general way that avoids casting. Thus, this patch will not be needed.

Do you have any idea about how to do this? @ikudrin My requirement here is: I need to add the endSymbol for asm streamer at the end of .text section to indicate the end of the text section.
Object streamer can easily do this by calling MCSymbol *endSection(Section) in emitDwarfLineTable, but this does not work for asm streamer. When we are generating assembly output for .debug_line section, we can not go back to .text section and emit an end symbol there. I think this is not supported.

[ikudrin]

In D94668#2553464, @shchenz wrote:

Do you have any idea about how to do this? @ikudrin My requirement here is: I need to add the endSymbol for asm streamer at the end of .text section to indicate the end of the text section.
Object streamer can easily do this by calling MCSymbol *endSection(Section) in emitDwarfLineTable, but this does not work for asm streamer. When we are generating assembly output for .debug_line section, we can not go back to .text section and emit an end symbol there. I think this is not supported.

Does that mean that endSection() does not work for your target? In that case, you need to fix it first, no?

[shchenz]

In D94668#2553568, @ikudrin wrote:

In D94668#2553464, @shchenz wrote:

Do you have any idea about how to do this? @ikudrin My requirement here is: I need to add the endSymbol for asm streamer at the end of .text section to indicate the end of the text section.
Object streamer can easily do this by calling MCSymbol *endSection(Section) in emitDwarfLineTable, but this does not work for asm streamer. When we are generating assembly output for .debug_line section, we can not go back to .text section and emit an end symbol there. I think this is not supported.

Does that mean that endSection() does not work for your target? In that case, you need to fix it first, no?

This seems not like a target specific problem. It should be by design, we can not call changeSection back to an existing section when we generate assembly output?.
endSection() will call changeSection and changeSection of MCAsmStreamer will call PrintSwitchToSection if target does not create a target-specific streamer.

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);
  }
}

In PrintSwitchToSection of MCSectionXCOFF::PrintSwitchToSection, we only generate some section headers in the assembly output, so I guess we can not switch to .text section and then emit a text end there, if we do so, we get pseudo assembly code like:

.text

.dwabbrev
...
.dwline
...
.text  #switch to .text
.text_end
.dwline_end #switch back to .dwline

I guess this is not allowed? MCSectionELF::PrintSwitchToSection also has same issue.

I have made some changes in D95518, and now the cast operation is not needed anymore. So this patch can be abandoned.

llvm/include/llvm/MC/MCAsmStreamer.h

+//===- MCObjectStreamer.h - MCStreamer Object File Interface ----*- 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
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_MC_MCASMSTREAMER_H
+#define LLVM_MC_MCASMSTREAMER_H
+
+#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/MC/MCAsmBackend.h"
+#include "llvm/MC/MCAsmInfo.h"
+#include "llvm/MC/MCAssembler.h"
+#include "llvm/MC/MCCodeEmitter.h"
+#include "llvm/MC/MCContext.h"
+#include "llvm/MC/MCExpr.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/MCStreamer.h"
+#include "llvm/Support/Format.h"
+#include "llvm/Support/FormattedStream.h"
+
+using namespace llvm;
+
+namespace llvm {
+
+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);
+    if (Assembler->getBackendPtr())
+      setAllowAutoPadding(Assembler->getBackend().allowAutoPadding());
+
+    Context.setUseNamesOnTempLabels(true);
+  }
+
+  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();
+  }
+
+  uint32_t getStreamerKind() const override { return StreamerKindAsm; }
+  static bool classof(const MCStreamer *S) {
+    return S->getStreamerKind() == StreamerKindAsm;
+  }
+
+  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;
+
+  StringRef getMnemonic(MCInst &MI) override {
+    return InstPrinter->getMnemonic(&MI).first;
+  }
+
+  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 emitXCOFFSymbolLinkageWithVisibility(MCSymbol *Symbol,
+                                            MCSymbolAttr Linakge,
+                                            MCSymbolAttr Visibility) override;
+  void emitXCOFFRenameDirective(const MCSymbol *Name,
+                                StringRef Rename) 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 emitIntValueInHexWithPadding(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 emitPseudoProbe(uint64_t Guid, uint64_t Index, uint64_t Type,
+                       uint64_t Attr,
+                       const MCPseudoProbeInlineStack &InlineStack) override;
+
+  void emitBundleAlignMode(unsigned AlignPow2) override;
+  void emitBundleLock(bool AlignToEnd) override;
+  void emitBundleUnlock() override;
+
+  Optional<std::pair<bool, std::string>>
+  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.
+
+#endif

llvm/include/llvm/MC/MCObjectStreamer.h

 
 protected:
   MCObjectStreamer(MCContext &Context, std::unique_ptr<MCAsmBackend> TAB,
                    std::unique_ptr<MCObjectWriter> OW,
                    std::unique_ptr<MCCodeEmitter> Emitter);
   ~MCObjectStreamer();
 
 public:
+  uint32_t getStreamerKind() const override { return StreamerKindObject; }
+  static bool classof(const MCStreamer *S) {
+    return S->getStreamerKind() == StreamerKindObject;
+  }
+
   /// state management
   void reset() override;
 
   /// Object streamers require the integrated assembler.
   bool isIntegratedAssemblerRequired() const override { return true; }
 
   void emitFrames(MCAsmBackend *MAB);
   void emitCFISections(bool EH, bool Debug) override;

llvm/include/llvm/MC/MCStreamer.h

protected:
   virtual void EmitWindowsUnwindTables();
 
   virtual void emitRawTextImpl(StringRef String);
 
   /// Returns true if the the .cv_loc directive is in the right section.
   bool checkCVLocSection(unsigned FuncId, unsigned FileNo, SMLoc Loc);
 
 public:
+
+  /// The kind of the streamer.
+  enum StreamerKind {
+    StreamerKindUnknown,
+    StreamerKindAsm,
+    StreamerKindObject,
+    StreamerKindNull,
+    StreamerKindRecord
+  };
+
   MCStreamer(const MCStreamer &) = delete;
   MCStreamer &operator=(const MCStreamer &) = delete;
   virtual ~MCStreamer();
 
+  virtual uint32_t getStreamerKind() const { return StreamerKindUnknown; };
+
   void visitUsedExpr(const MCExpr &Expr);
   virtual void visitUsedSymbol(const MCSymbol &Sym);
 
   void setTargetStreamer(MCTargetStreamer *TS) {
     TargetStreamer.reset(TS);
   }
 
   void setStartTokLocPtr(const SMLoc *Loc) { StartTokLocPtr = Loc; }

llvm/lib/MC/MCAsmStreamer.cpp

 //===- 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/MCAsmStreamer.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/MCPseudoProbe.h"
-#include "llvm/MC/MCRegister.h"
 #include "llvm/MC/MCRegisterInfo.h"
 #include "llvm/MC/MCSectionMachO.h"
-#include "llvm/MC/MCStreamer.h"
 #include "llvm/MC/MCSymbolXCOFF.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);
-    if (Assembler->getBackendPtr())
-      setAllowAutoPadding(Assembler->getBackend().allowAutoPadding());
-
-    Context.setUseNamesOnTempLabels(true);
-  }
-
-  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;
-
-  StringRef getMnemonic(MCInst &MI) override {
-    return InstPrinter->getMnemonic(&MI).first;
-  }
-
-  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 emitXCOFFSymbolLinkageWithVisibility(MCSymbol *Symbol,
-                                            MCSymbolAttr Linakge,
-                                            MCSymbolAttr Visibility) override;
-  void emitXCOFFRenameDirective(const MCSymbol *Name,
-                                StringRef Rename) 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 emitIntValueInHexWithPadding(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 emitPseudoProbe(uint64_t Guid, uint64_t Index, uint64_t Type,
-                       uint64_t Attr,
-                       const MCPseudoProbeInlineStack &InlineStack) override;
-
-  void emitBundleAlignMode(unsigned AlignPow2) override;
-  void emitBundleLock(bool AlignToEnd) override;
-  void emitBundleUnlock() override;
-
-  Optional<std::pair<bool, std::string>>
-  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.
 }

llvm/lib/MC/MCNullStreamer.cpp

 using namespace llvm;
 
 namespace {
 
   class MCNullStreamer : public MCStreamer {
   public:
     MCNullStreamer(MCContext &Context) : MCStreamer(Context) {}
 
+    uint32_t getStreamerKind() const override { return StreamerKindNull; }
+    static bool classof(const MCStreamer *S) {
+      return S->getStreamerKind() == StreamerKindNull;
+    }
+
     /// @name MCStreamer Interface
     /// @{
 
     bool hasRawTextSupport() const override { return true; }
     void emitRawTextImpl(StringRef String) override {}
 
     bool emitSymbolAttribute(MCSymbol *Symbol,
                              MCSymbolAttr Attribute) override {

llvm/lib/Object/RecordStreamer.h

private:
   void markDefined(const MCSymbol &Symbol);
   void markGlobal(const MCSymbol &Symbol, MCSymbolAttr Attribute);
   void markUsed(const MCSymbol &Symbol);
   void visitUsedSymbol(const MCSymbol &Sym) override;
 
 public:
   RecordStreamer(MCContext &Context, const Module &M);
 
+  uint32_t getStreamerKind() const override { return StreamerKindRecord; }
+  static bool classof(const MCStreamer *S) {
+    return S->getStreamerKind() == StreamerKindRecord;
+  }
+
   void emitInstruction(const MCInst &Inst, const MCSubtargetInfo &STI) override;
   void emitLabel(MCSymbol *Symbol, SMLoc Loc = SMLoc()) override;
   void emitAssignment(MCSymbol *Symbol, const MCExpr *Value) override;
   bool emitSymbolAttribute(MCSymbol *Symbol, MCSymbolAttr Attribute) override;
   void emitZerofill(MCSection *Section, MCSymbol *Symbol, uint64_t Size,
                     unsigned ByteAlignment, SMLoc Loc = SMLoc()) override;
   void emitCommonSymbol(MCSymbol *Symbol, uint64_t Size,
                         unsigned ByteAlignment) override;