Revert "[CodeView] Use assembler directives for line tables"

This reverts commit r259117.

The LineInfo constructor is defined in the codeview library and we have
to link against it now. Doing that isn't trivial, so reverting for now.

llvm-svn: 259126

8 files changed, 8 insertions, 580 deletions

diff --git a/llvm/lib/MC/CMakeLists.txt b/llvm/lib/MC/CMakeLists.txt
index a04f16c6ea7..d1aac8104a3 100644
--- a/llvm/lib/MC/CMakeLists.txt
+++ b/llvm/lib/MC/CMakeLists.txt
@@ -10,7 +10,6 @@ add_llvm_library(LLVMMC
   MCAssembler.cpp
   MCCodeEmitter.cpp
   MCCodeGenInfo.cpp
-  MCCodeView.cpp
   MCContext.cpp
   MCDwarf.cpp
   MCELFObjectTargetWriter.cpp
diff --git a/llvm/lib/MC/MCAsmStreamer.cpp b/llvm/lib/MC/MCAsmStreamer.cpp
index d9382c5df9f..2de36f8561c 100644
--- a/llvm/lib/MC/MCAsmStreamer.cpp
+++ b/llvm/lib/MC/MCAsmStreamer.cpp
@@ -199,15 +199,6 @@ public:
                              StringRef FileName) override;
   MCSymbol *getDwarfLineTableSymbol(unsigned CUID) override;
 
-  unsigned EmitCVFileDirective(unsigned FileNo, StringRef Filename) override;
-  void EmitCVLocDirective(unsigned FunctionId, unsigned FileNo, unsigned Line,
-                          unsigned Column, bool PrologueEnd, bool IsStmt,
-                          StringRef FileName) override;
-  void EmitCVLinetableDirective(unsigned FunctionId, const MCSymbol *FnStart,
-                                const MCSymbol *FnEnd) override;
-  void EmitCVStringTableDirective() override;
-  void EmitCVFileChecksumsDirective() override;
-
   void EmitIdent(StringRef IdentString) override;
   void EmitCFISections(bool EH, bool Debug) override;
   void EmitCFIDefCfa(int64_t Register, int64_t Offset) override;
@@ -963,69 +954,6 @@ MCSymbol *MCAsmStreamer::getDwarfLineTableSymbol(unsigned CUID) {
   return MCStreamer::getDwarfLineTableSymbol(0);
 }
 
-unsigned MCAsmStreamer::EmitCVFileDirective(unsigned FileNo,
-                                            StringRef Filename) {
-  if (!getContext().getCVFile(Filename, FileNo))
-    return 0;
-
-  OS << "\t.cv_file\t" << FileNo << ' ';
-
-  PrintQuotedString(Filename, OS);
-  EmitEOL();
-
-  return FileNo;
-}
-
-void MCAsmStreamer::EmitCVLocDirective(unsigned FunctionId, unsigned FileNo,
-                                       unsigned Line, unsigned Column,
-                                       bool PrologueEnd, bool IsStmt,
-                                       StringRef FileName) {
-  OS << "\t.cv_loc\t" << FunctionId << " " << FileNo << " " << Line << " "
-     << Column;
-  if (PrologueEnd)
-    OS << " prologue_end";
-
-  unsigned OldIsStmt = getContext().getCurrentCVLoc().isStmt();
-  if (IsStmt != OldIsStmt) {
-    OS << " is_stmt ";
-
-    if (IsStmt)
-      OS << "1";
-    else
-      OS << "0";
-  }
-
-  if (IsVerboseAsm) {
-    OS.PadToColumn(MAI->getCommentColumn());
-    OS << MAI->getCommentString() << ' ' << FileName << ':'
-       << Line << ':' << Column;
-  }
-  EmitEOL();
-  this->MCStreamer::EmitCVLocDirective(FunctionId, FileNo, Line, Column,
-                                       PrologueEnd, IsStmt, FileName);
-}
-
-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::EmitCVStringTableDirective() {
-  OS << "\t.cv_stringtable";
-  EmitEOL();
-}
-
-void MCAsmStreamer::EmitCVFileChecksumsDirective() {
-  OS << "\t.cv_filechecksums";
-  EmitEOL();
-}
-
 void MCAsmStreamer::EmitIdent(StringRef IdentString) {
   assert(MAI->hasIdentDirective() && ".ident directive not supported");
   OS << "\t.ident\t";
diff --git a/llvm/lib/MC/MCCodeView.cpp b/llvm/lib/MC/MCCodeView.cpp
deleted file mode 100644
index 992edd0a8bc..00000000000
--- a/llvm/lib/MC/MCCodeView.cpp
+++ /dev/null
@@ -1,222 +0,0 @@
-//===- MCCodeView.h - Machine Code CodeView support -------------*- C++ -*-===//
-//
-//                     The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-//
-// Holds state from .cv_file and .cv_loc directives for later emission.
-//
-//===----------------------------------------------------------------------===//
-
-#include "llvm/MC/MCCodeView.h"
-#include "llvm/ADT/STLExtras.h"
-#include "llvm/DebugInfo/CodeView/CodeView.h"
-#include "llvm/DebugInfo/CodeView/Line.h"
-#include "llvm/MC/MCContext.h"
-#include "llvm/MC/MCObjectStreamer.h"
-#include "llvm/Support/COFF.h"
-
-using namespace llvm;
-using namespace llvm::codeview;
-
-CodeViewContext::CodeViewContext() {}
-
-CodeViewContext::~CodeViewContext() {
-  // If someone inserted strings into the string table but never actually
-  // emitted them somewhere, clean up the fragment.
-  if (!InsertedStrTabFragment)
-    delete StrTabFragment;
-}
-
-/// This is a valid number for use with .cv_loc if we've already seen a .cv_file
-/// for it.
-bool CodeViewContext::isValidFileNumber(unsigned FileNumber) const {
-  unsigned Idx = FileNumber - 1;
-  if (Idx < Filenames.size())
-    return !Filenames[Idx].empty();
-  return false;
-}
-
-bool CodeViewContext::addFile(unsigned FileNumber, StringRef Filename) {
-  assert(FileNumber > 0);
-  Filename = addToStringTable(Filename);
-  unsigned Idx = FileNumber - 1;
-  if (Idx >= Filenames.size())
-    Filenames.resize(Idx + 1);
-
-  if (Filename.empty())
-    Filename = "<stdin>";
-
-  if (!Filenames[Idx].empty())
-    return false;
-
-  // FIXME: We should store the string table offset of the filename, rather than
-  // the filename itself for efficiency.
-  Filename = addToStringTable(Filename);
-
-  Filenames[Idx] = Filename;
-  return true;
-}
-
-MCDataFragment *CodeViewContext::getStringTableFragment() {
-  if (!StrTabFragment) {
-    StrTabFragment = new MCDataFragment();
-    // Start a new string table out with a null byte.
-    StrTabFragment->getContents().push_back('\0');
-  }
-  return StrTabFragment;
-}
-
-StringRef CodeViewContext::addToStringTable(StringRef S) {
-  SmallVectorImpl<char> &Contents = getStringTableFragment()->getContents();
-  auto Insertion =
-      StringTable.insert(std::make_pair(S, unsigned(Contents.size())));
-  // Return the string from the table, since it is stable.
-  S = Insertion.first->first();
-  if (Insertion.second) {
-    // The string map key is always null terminated.
-    Contents.append(S.begin(), S.end() + 1);
-  }
-  return S;
-}
-
-unsigned CodeViewContext::getStringTableOffset(StringRef S) {
-  // A string table offset of zero is always the empty string.
-  if (S.empty())
-    return 0;
-  auto I = StringTable.find(S);
-  assert(I != StringTable.end());
-  return I->second;
-}
-
-void CodeViewContext::emitStringTable(MCObjectStreamer &OS) {
-  MCContext &Ctx = OS.getContext();
-  MCSymbol *StringBegin = Ctx.createTempSymbol("strtab_begin"),
-           *StringEnd = Ctx.createTempSymbol("strtab_end");
-
-  OS.EmitIntValue(unsigned(ModuleSubstreamKind::StringTable), 4);
-  OS.emitAbsoluteSymbolDiff(StringEnd, StringBegin, 4);
-  OS.EmitLabel(StringBegin);
-
-  // Put the string table data fragment here, if we haven't already put it
-  // somewhere else. If somebody wants two string tables in their .s file, one
-  // will just be empty.
-  if (!InsertedStrTabFragment) {
-    OS.insert(getStringTableFragment());
-    InsertedStrTabFragment = true;
-  }
-
-  OS.EmitValueToAlignment(4, 0);
-
-  OS.EmitLabel(StringEnd);
-}
-
-void CodeViewContext::emitFileChecksums(MCObjectStreamer &OS) {
-  MCContext &Ctx = OS.getContext();
-  MCSymbol *FileBegin = Ctx.createTempSymbol("filechecksums_begin"),
-           *FileEnd = Ctx.createTempSymbol("filechecksums_end");
-
-  OS.EmitIntValue(unsigned(ModuleSubstreamKind::FileChecksums), 4);
-  OS.emitAbsoluteSymbolDiff(FileEnd, FileBegin, 4);
-  OS.EmitLabel(FileBegin);
-
-  // Emit an array of FileChecksum entries. We index into this table using the
-  // user-provided file number. Each entry is currently 8 bytes, as we don't
-  // emit checksums.
-  for (StringRef Filename : Filenames) {
-    OS.EmitIntValue(getStringTableOffset(Filename), 4);
-    // Zero the next two fields and align back to 4 bytes. This indicates that
-    // no checksum is present.
-    OS.EmitIntValue(0, 4);
-  }
-
-  OS.EmitLabel(FileEnd);
-}
-
-void CodeViewContext::emitLineTableForFunction(MCObjectStreamer &OS,
-                                               unsigned FuncId,
-                                               const MCSymbol *FuncBegin,
-                                               const MCSymbol *FuncEnd) {
-  MCContext &Ctx = OS.getContext();
-  MCSymbol *LineBegin = Ctx.createTempSymbol("linetable_begin"),
-           *LineEnd = Ctx.createTempSymbol("linetable_end");
-
-  OS.EmitIntValue(unsigned(ModuleSubstreamKind::Lines), 4);
-  OS.emitAbsoluteSymbolDiff(LineEnd, LineBegin, 4);
-  OS.EmitLabel(LineBegin);
-  OS.EmitCOFFSecRel32(FuncBegin);
-  OS.EmitCOFFSectionIndex(FuncBegin);
-
-  // Actual line info.
-  ArrayRef<MCCVLineEntry> Locs = getFunctionLineEntries(FuncId);
-  bool HaveColumns = any_of(Locs, [](const MCCVLineEntry &LineEntry) {
-    return LineEntry.getColumn() != 0;
-  });
-  OS.EmitIntValue(HaveColumns ? int(codeview::LineFlags::HaveColumns) : 0, 2);
-  OS.emitAbsoluteSymbolDiff(FuncEnd, FuncBegin, 4);
-
-  for (auto I = Locs.begin(), E = Locs.end(); I != E;) {
-    // Emit a file segment for the run of locations that share a file id.
-    unsigned CurFileNum = I->getFileNum();
-    auto FileSegEnd =
-        std::find_if(I, E, [CurFileNum](const MCCVLineEntry &Loc) {
-          return Loc.getFileNum() != CurFileNum;
-        });
-    unsigned EntryCount = FileSegEnd - I;
-    OS.AddComment("Segment for file '" + Twine(Filenames[CurFileNum - 1]) +
-                  "' begins");
-    OS.EmitIntValue(8 * (CurFileNum - 1), 4);
-    OS.EmitIntValue(EntryCount, 4);
-    uint32_t SegmentSize = 12;
-    SegmentSize += 8 * EntryCount;
-    if (HaveColumns)
-      SegmentSize += 4 * EntryCount;
-    OS.EmitIntValue(SegmentSize, 4);
-
-    for (auto J = I; J != FileSegEnd; ++J) {
-      OS.emitAbsoluteSymbolDiff(J->getLabel(), FuncBegin, 4);
-      unsigned LineData = J->getLine();
-      if (J->isStmt())
-        LineData |= codeview::LineInfo::StatementFlag;
-      OS.EmitIntValue(LineData, 4);
-    }
-    if (HaveColumns) {
-      for (auto J = I; J != FileSegEnd; ++J) {
-        OS.EmitIntValue(J->getColumn(), 2);
-        OS.EmitIntValue(0, 2);
-      }
-    }
-    I = FileSegEnd;
-  }
-  OS.EmitLabel(LineEnd);
-}
-
-//
-// This is called when an instruction is assembled into the specified section
-// and if there is information from the last .cv_loc directive that has yet to have
-// a line entry made for it is made.
-//
-void MCCVLineEntry::Make(MCObjectStreamer *MCOS) {
-  if (!MCOS->getContext().getCVLocSeen())
-    return;
-
-  // Create a symbol at in the current section for use in the line entry.
-  MCSymbol *LineSym = MCOS->getContext().createTempSymbol();
-  // Set the value of the symbol to use for the MCCVLineEntry.
-  MCOS->EmitLabel(LineSym);
-
-  // Get the current .loc info saved in the context.
-  const MCCVLoc &CVLoc = MCOS->getContext().getCurrentCVLoc();
-
-  // Create a (local) line entry with the symbol and the current .loc info.
-  MCCVLineEntry LineEntry(LineSym, CVLoc);
-
-  // clear CVLocSeen saying the current .loc info is now used.
-  MCOS->getContext().clearCVLocSeen();
-
-  // Add the line entry to this section's entries.
-  MCOS->getContext().getCVContext().addLineEntry(LineEntry);
-}
diff --git a/llvm/lib/MC/MCContext.cpp b/llvm/lib/MC/MCContext.cpp
index c5243ef62c9..b5ad518d033 100644
--- a/llvm/lib/MC/MCContext.cpp
+++ b/llvm/lib/MC/MCContext.cpp
@@ -12,7 +12,6 @@
 #include "llvm/ADT/Twine.h"
 #include "llvm/MC/MCAssembler.h"
 #include "llvm/MC/MCAsmInfo.h"
-#include "llvm/MC/MCCodeView.h"
 #include "llvm/MC/MCDwarf.h"
 #include "llvm/MC/MCLabel.h"
 #include "llvm/MC/MCObjectFileInfo.h"
@@ -91,8 +90,6 @@ void MCContext::reset() {
   DwarfCompileUnitID = 0;
   CurrentDwarfLoc = MCDwarfLoc(0, 0, 0, DWARF2_FLAG_IS_STMT, 0, 0);
 
-  CVContext.reset();
-
   MachOUniquingMap.clear();
   ELFUniquingMap.clear();
   COFFUniquingMap.clear();
@@ -477,20 +474,6 @@ void MCContext::finalizeDwarfSections(MCStreamer &MCOS) {
       [&](MCSection *Sec) { return !MCOS.mayHaveInstructions(*Sec); });
 }
 
-CodeViewContext &MCContext::getCVContext() {
-  if (!CVContext.get())
-    CVContext.reset(new CodeViewContext);
-  return *CVContext.get();
-}
-
-unsigned MCContext::getCVFile(StringRef FileName, unsigned FileNumber) {
-  return getCVContext().addFile(FileNumber, FileName) ? FileNumber : 0;
-}
-
-bool MCContext::isValidCVFileNumber(unsigned FileNumber) {
-  return getCVContext().isValidFileNumber(FileNumber);
-}
-
 //===----------------------------------------------------------------------===//
 // Error Reporting
 //===----------------------------------------------------------------------===//
diff --git a/llvm/lib/MC/MCObjectStreamer.cpp b/llvm/lib/MC/MCObjectStreamer.cpp
index 71d578aca9d..39755e5b0a8 100644
--- a/llvm/lib/MC/MCObjectStreamer.cpp
+++ b/llvm/lib/MC/MCObjectStreamer.cpp
@@ -125,7 +125,6 @@ void MCObjectStreamer::EmitValueImpl(const MCExpr *Value, unsigned Size,
   MCDataFragment *DF = getOrCreateDataFragment();
   flushPendingLabels(DF, DF->getContents().size());
 
-  MCCVLineEntry::Make(this);
   MCDwarfLineEntry::Make(this, getCurrentSection().first);
 
   // Avoid fixups when possible.
@@ -233,7 +232,6 @@ void MCObjectStreamer::EmitInstruction(const MCInst &Inst,
 
   // Now that a machine instruction has been assembled into this section, make
   // a line entry for any .loc directive that has been seen.
-  MCCVLineEntry::Make(this);
   MCDwarfLineEntry::Make(this, getCurrentSection().first);
 
   // If this instruction doesn't need relaxation, just emit it as data.
@@ -364,36 +362,7 @@ void MCObjectStreamer::EmitDwarfAdvanceFrameAddr(const MCSymbol *LastLabel,
   insert(new MCDwarfCallFrameFragment(*AddrDelta));
 }
 
-void MCObjectStreamer::EmitCVLocDirective(unsigned FunctionId, unsigned FileNo,
-                                          unsigned Line, unsigned Column,
-                                          bool PrologueEnd, bool IsStmt,
-                                          StringRef FileName) {
-  // In case we see two .cv_loc directives in a row, make sure the
-  // first one gets a line entry.
-  MCCVLineEntry::Make(this);
-
-  this->MCStreamer::EmitCVLocDirective(FunctionId, FileNo, Line, Column,
-                                       PrologueEnd, IsStmt, FileName);
-}
-
-void MCObjectStreamer::EmitCVLinetableDirective(unsigned FunctionId,
-                                                const MCSymbol *Begin,
-                                                const MCSymbol *End) {
-  getContext().getCVContext().emitLineTableForFunction(*this, FunctionId, Begin,
-                                                       End);
-  this->MCStreamer::EmitCVLinetableDirective(FunctionId, Begin, End);
-}
-
-void MCObjectStreamer::EmitCVStringTableDirective() {
-  getContext().getCVContext().emitStringTable(*this);
-}
-void MCObjectStreamer::EmitCVFileChecksumsDirective() {
-  getContext().getCVContext().emitFileChecksums(*this);
-}
-
-
 void MCObjectStreamer::EmitBytes(StringRef Data) {
-  MCCVLineEntry::Make(this);
   MCDwarfLineEntry::Make(this, getCurrentSection().first);
   MCDataFragment *DF = getOrCreateDataFragment();
   flushPendingLabels(DF, DF->getContents().size());
diff --git a/llvm/lib/MC/MCParser/AsmParser.cpp b/llvm/lib/MC/MCParser/AsmParser.cpp
index 360de5db883..b1814f8c8ff 100644
--- a/llvm/lib/MC/MCParser/AsmParser.cpp
+++ b/llvm/lib/MC/MCParser/AsmParser.cpp
@@ -357,8 +357,6 @@ private:
     DK_IFNB, DK_IFC, DK_IFEQS, DK_IFNC, DK_IFNES, DK_IFDEF, DK_IFNDEF,
     DK_IFNOTDEF, DK_ELSEIF, DK_ELSE, DK_ENDIF,
     DK_SPACE, DK_SKIP, DK_FILE, DK_LINE, DK_LOC, DK_STABS,
-    DK_CV_FILE, DK_CV_LOC, DK_CV_LINETABLE, DK_CV_STRINGTABLE,
-    DK_CV_FILECHECKSUMS,
     DK_CFI_SECTIONS, DK_CFI_STARTPROC, DK_CFI_ENDPROC, DK_CFI_DEF_CFA,
     DK_CFI_DEF_CFA_OFFSET, DK_CFI_ADJUST_CFA_OFFSET, DK_CFI_DEF_CFA_REGISTER,
     DK_CFI_OFFSET, DK_CFI_REL_OFFSET, DK_CFI_PERSONALITY, DK_CFI_LSDA,
@@ -396,13 +394,6 @@ private:
   bool parseDirectiveLoc();
   bool parseDirectiveStabs();
 
-  // ".cv_file", ".cv_loc", ".cv_linetable"
-  bool parseDirectiveCVFile();
-  bool parseDirectiveCVLoc();
-  bool parseDirectiveCVLinetable();
-  bool parseDirectiveCVStringTable();
-  bool parseDirectiveCVFileChecksums();
-
   // .cfi directives
   bool parseDirectiveCFIRegister(SMLoc DirectiveLoc);
   bool parseDirectiveCFIWindowSave();
@@ -1647,16 +1638,6 @@ bool AsmParser::parseStatement(ParseStatementInfo &Info,
       return parseDirectiveLoc();
     case DK_STABS:
       return parseDirectiveStabs();
-    case DK_CV_FILE:
-      return parseDirectiveCVFile();
-    case DK_CV_LOC:
-      return parseDirectiveCVLoc();
-    case DK_CV_LINETABLE:
-      return parseDirectiveCVLinetable();
-    case DK_CV_STRINGTABLE:
-      return parseDirectiveCVStringTable();
-    case DK_CV_FILECHECKSUMS:
-      return parseDirectiveCVFileChecksums();
     case DK_CFI_SECTIONS:
       return parseDirectiveCFISections();
     case DK_CFI_STARTPROC:
@@ -3089,156 +3070,6 @@ bool AsmParser::parseDirectiveStabs() {
   return TokError("unsupported directive '.stabs'");
 }
 
-/// parseDirectiveCVFile
-/// ::= .cv_file number filename
-bool AsmParser::parseDirectiveCVFile() {
-  SMLoc FileNumberLoc = getLexer().getLoc();
-  if (getLexer().isNot(AsmToken::Integer))
-    return TokError("expected file number in '.cv_file' directive");
-
-  int64_t FileNumber = getTok().getIntVal();
-  Lex();
-
-  if (FileNumber < 1)
-    return TokError("file number less than one");
-
-  if (getLexer().isNot(AsmToken::String))
-    return TokError("unexpected token in '.cv_file' directive");
-
-  // Usually the directory and filename together, otherwise just the directory.
-  // Allow the strings to have escaped octal character sequence.
-  std::string Filename;
-  if (parseEscapedString(Filename))
-    return true;
-  Lex();
-
-  if (getLexer().isNot(AsmToken::EndOfStatement))
-    return TokError("unexpected token in '.cv_file' directive");
-
-  if (getStreamer().EmitCVFileDirective(FileNumber, Filename) == 0)
-    Error(FileNumberLoc, "file number already allocated");
-
-  return false;
-}
-
-/// parseDirectiveCVLoc
-/// ::= .cv_loc FunctionId FileNumber [LineNumber] [ColumnPos] [prologue_end]
-///                                [is_stmt VALUE]
-/// The first number is a file number, must have been previously assigned with
-/// a .file directive, the second number is the line number and optionally the
-/// third number is a column position (zero if not specified).  The remaining
-/// optional items are .loc sub-directives.
-bool AsmParser::parseDirectiveCVLoc() {
-  if (getLexer().isNot(AsmToken::Integer))
-    return TokError("unexpected token in '.cv_loc' directive");
-
-  int64_t FunctionId = getTok().getIntVal();
-  if (FunctionId < 0)
-    return TokError("function id less than zero in '.cv_loc' directive");
-  Lex();
-
-  int64_t FileNumber = getTok().getIntVal();
-  if (FileNumber < 1)
-    return TokError("file number less than one in '.cv_loc' directive");
-  if (!getContext().isValidCVFileNumber(FileNumber))
-    return TokError("unassigned file number in '.cv_loc' directive");
-  Lex();
-
-  int64_t LineNumber = 0;
-  if (getLexer().is(AsmToken::Integer)) {
-    LineNumber = getTok().getIntVal();
-    if (LineNumber < 0)
-      return TokError("line number less than zero in '.cv_loc' directive");
-    Lex();
-  }
-
-  int64_t ColumnPos = 0;
-  if (getLexer().is(AsmToken::Integer)) {
-    ColumnPos = getTok().getIntVal();
-    if (ColumnPos < 0)
-      return TokError("column position less than zero in '.cv_loc' directive");
-    Lex();
-  }
-
-  bool PrologueEnd = false;
-  uint64_t IsStmt = 0;
-  while (getLexer().isNot(AsmToken::EndOfStatement)) {
-    StringRef Name;
-    SMLoc Loc = getTok().getLoc();
-    if (parseIdentifier(Name))
-      return TokError("unexpected token in '.cv_loc' directive");
-
-    if (Name == "prologue_end")
-      PrologueEnd = true;
-    else if (Name == "is_stmt") {
-      Loc = getTok().getLoc();
-      const MCExpr *Value;
-      if (parseExpression(Value))
-        return true;
-      // The expression must be the constant 0 or 1.
-      IsStmt = ~0ULL;
-      if (const auto *MCE = dyn_cast<MCConstantExpr>(Value))
-        IsStmt = MCE->getValue();
-
-      if (IsStmt > 1)
-        return Error(Loc, "is_stmt value not 0 or 1");
-    } else {
-      return Error(Loc, "unknown sub-directive in '.cv_loc' directive");
-    }
-  }
-
-  getStreamer().EmitCVLocDirective(FunctionId, FileNumber, LineNumber,
-                                   ColumnPos, PrologueEnd, IsStmt, StringRef());
-  return false;
-}
-
-/// parseDirectiveCVLinetable
-/// ::= .cv_linetable FunctionId, FnStart, FnEnd
-bool AsmParser::parseDirectiveCVLinetable() {
-  int64_t FunctionId = getTok().getIntVal();
-  if (FunctionId < 0)
-    return TokError("function id less than zero in '.cv_linetable' directive");
-  Lex();
-
-  if (Lexer.isNot(AsmToken::Comma))
-    return TokError("unexpected token in '.cv_linetable' directive");
-  Lex();
-
-  SMLoc Loc = getLexer().getLoc();
-  StringRef FnStartName;
-  if (parseIdentifier(FnStartName))
-    return Error(Loc, "expected identifier in directive");
-
-  if (Lexer.isNot(AsmToken::Comma))
-    return TokError("unexpected token in '.cv_linetable' directive");
-  Lex();
-
-  Loc = getLexer().getLoc();
-  StringRef FnEndName;
-  if (parseIdentifier(FnEndName))
-    return Error(Loc, "expected identifier in directive");
-
-  MCSymbol *FnStartSym = getContext().getOrCreateSymbol(FnStartName);
-  MCSymbol *FnEndSym = getContext().getOrCreateSymbol(FnEndName);
-
-  getStreamer().EmitCVLinetableDirective(FunctionId, FnStartSym, FnEndSym);
-  return false;
-}
-
-/// parseDirectiveCVStringTable
-/// ::= .cv_stringtable
-bool AsmParser::parseDirectiveCVStringTable() {
-  getStreamer().EmitCVStringTableDirective();
-  return false;
-}
-
-/// parseDirectiveCVFileChecksums
-/// ::= .cv_filechecksums
-bool AsmParser::parseDirectiveCVFileChecksums() {
-  getStreamer().EmitCVFileChecksumsDirective();
-  return false;
-}
-
 /// parseDirectiveCFISections
 /// ::= .cfi_sections section [, section]
 bool AsmParser::parseDirectiveCFISections() {
@@ -4550,11 +4381,6 @@ void AsmParser::initializeDirectiveKindMap() {
   DirectiveKindMap[".line"] = DK_LINE;
   DirectiveKindMap[".loc"] = DK_LOC;
   DirectiveKindMap[".stabs"] = DK_STABS;
-  DirectiveKindMap[".cv_file"] = DK_CV_FILE;
-  DirectiveKindMap[".cv_loc"] = DK_CV_LOC;
-  DirectiveKindMap[".cv_linetable"] = DK_CV_LINETABLE;
-  DirectiveKindMap[".cv_stringtable"] = DK_CV_STRINGTABLE;
-  DirectiveKindMap[".cv_filechecksums"] = DK_CV_FILECHECKSUMS;
   DirectiveKindMap[".sleb128"] = DK_SLEB128;
   DirectiveKindMap[".uleb128"] = DK_ULEB128;
   DirectiveKindMap[".cfi_sections"] = DK_CFI_SECTIONS;
diff --git a/llvm/lib/MC/MCStreamer.cpp b/llvm/lib/MC/MCStreamer.cpp
index adae5d73ce5..836b4054464 100644
--- a/llvm/lib/MC/MCStreamer.cpp
+++ b/llvm/lib/MC/MCStreamer.cpp
@@ -180,22 +180,6 @@ void MCStreamer::EnsureValidDwarfFrame() {
     report_fatal_error("No open frame");
 }
 
-unsigned MCStreamer::EmitCVFileDirective(unsigned FileNo, StringRef Filename) {
-  return getContext().getCVFile(Filename, FileNo);
-}
-
-void MCStreamer::EmitCVLocDirective(unsigned FunctionId, unsigned FileNo,
-                                    unsigned Line, unsigned Column,
-                                    bool PrologueEnd, bool IsStmt,
-                                    StringRef FileName) {
-  getContext().setCurrentCVLoc(FunctionId, FileNo, Line, Column, PrologueEnd,
-                               IsStmt);
-}
-
-void MCStreamer::EmitCVLinetableDirective(unsigned FunctionId,
-                                          const MCSymbol *Begin,
-                                          const MCSymbol *End) {}
-
 void MCStreamer::EmitEHSymAttributes(const MCSymbol *Symbol,
                                      MCSymbol *EHSymbol) {
 }
diff --git a/llvm/lib/MC/StringTableBuilder.cpp b/llvm/lib/MC/StringTableBuilder.cpp
index f50e098e6e4..80e552287b3 100644
--- a/llvm/lib/MC/StringTableBuilder.cpp
+++ b/llvm/lib/MC/StringTableBuilder.cpp
@@ -16,22 +16,7 @@
 
 using namespace llvm;
 
-StringTableBuilder::StringTableBuilder(Kind K) : K(K) {
-  // Account for leading bytes in table so that offsets returned from add are
-  // correct.
-  switch (K) {
-  case RAW:
-    Size = 0;
-    break;
-  case MachO:
-  case ELF:
-    Size = 1;
-    break;
-  case WinCOFF:
-    Size = 4;
-    break;
-  }
-}
+StringTableBuilder::StringTableBuilder(Kind K) : K(K) {}
 
 typedef std::pair<StringRef, size_t> StringPair;
 
@@ -77,32 +62,13 @@ tailcall:
 }
 
 void StringTableBuilder::finalize() {
-  finalizeStringTable(/*Optimize=*/true);
-}
-
-void StringTableBuilder::finalizeInOrder() {
-  finalizeStringTable(/*Optimize=*/false);
-}
-
-void StringTableBuilder::finalizeStringTable(bool Optimize) {
-  typedef std::pair<StringRef, size_t> StringOffsetPair;
-  std::vector<StringOffsetPair *> Strings;
+  std::vector<std::pair<StringRef, size_t> *> Strings;
   Strings.reserve(StringIndexMap.size());
-  for (StringOffsetPair &P : StringIndexMap)
+  for (std::pair<StringRef, size_t> &P : StringIndexMap)
     Strings.push_back(&P);
 
-  if (!Strings.empty()) {
-    // If we're optimizing, sort by name. If not, sort by previously assigned
-    // offset.
-    if (Optimize) {
-      multikey_qsort(&Strings[0], &Strings[0] + Strings.size(), 0);
-    } else {
-      std::sort(Strings.begin(), Strings.end(),
-                [](const StringOffsetPair *LHS, const StringOffsetPair *RHS) {
-                  return LHS->second < RHS->second;
-                });
-    }
-  }
+  if (!Strings.empty())
+    multikey_qsort(&Strings[0], &Strings[0] + Strings.size(), 0);
 
   switch (K) {
   case RAW:
@@ -119,22 +85,17 @@ void StringTableBuilder::finalizeStringTable(bool Optimize) {
   }
 
   StringRef Previous;
-  for (StringOffsetPair *P : Strings) {
+  for (std::pair<StringRef, size_t> *P : Strings) {
     StringRef S = P->first;
     if (K == WinCOFF)
       assert(S.size() > COFF::NameSize && "Short string in COFF string table!");
 
-    if (Optimize && Previous.endswith(S)) {
+    if (Previous.endswith(S)) {
       P->second = StringTable.size() - S.size() - (K != RAW);
       continue;
     }
 
-    if (Optimize)
-      P->second = StringTable.size();
-    else
-      assert(P->second == StringTable.size() &&
-             "different strtab offset after finalization");
-
+    P->second = StringTable.size();
     StringTable += S;
     if (K != RAW)
       StringTable += '\x00';