[llvm] ee2c0f7 - [ms] [llvm-ml] Add a draft MASM parser

Eric Astor via llvm-commits llvm-commits at lists.llvm.org
Sun Feb 16 09:31:39 PST 2020


Author: Eric Astor
Date: 2020-02-16T12:30:46-05:00
New Revision: ee2c0f76d74cc03e54389926c9e626987e1408c3

URL: https://github.com/llvm/llvm-project/commit/ee2c0f76d74cc03e54389926c9e626987e1408c3
DIFF: https://github.com/llvm/llvm-project/commit/ee2c0f76d74cc03e54389926c9e626987e1408c3.diff

LOG: [ms] [llvm-ml] Add a draft MASM parser

Summary:
Many directives are unavailable, and support for others may be limited.

This first draft has preliminary support for:
    - conditional directives (including errors),
    - data allocation (unsigned types up to 8 bytes, and ALIGN),
    - equates/variables (numeric and text),
    - and procedure directives (without parameters),
as well as COMMENT, ECHO, INCLUDE, INCLUDELIB, PUBLIC, and EXTERN. Text variables (aka text macros) are expanded in-place wherever the identifier occurs.

We deliberately ignore all ml.exe processor directives.

Prominent features not yet supported:
    - structs
    - macros (both procedures and functions)
    - procedures (with specified parameters)
    - substitution & expansion operators

Conditional directives are complicated by the fact that "ifdef rax" is a valid way to check if a file is being assembled for a 64-bit x86 processor; we add support for "ifdef <register>" in general, which requires adding a tryParseRegister method to all MCTargetAsmParsers. (Some targets require backtracking in the non-register case.)

Reviewers: rnk, thakis

Reviewed By: thakis

Subscribers: kerbowa, merge_guards_bot, wuzish, arsenm, dschuff, jyknight, dylanmckay, sdardis, nemanjai, jvesely, mgorny, sbc100, jgravelle-google, hiraditya, aheejin, kbarton, fedor.sergeev, asb, rbar, johnrusso, simoncook, sabuasal, niosHD, jrtc27, MaskRay, zzheng, edward-jones, atanasyan, rogfer01, MartinMosbeck, brucehoult, the_o, PkmX, jocewei, jsji, Jim, s.egerton, pzheng, sameer.abuasal, apazos, luismarques, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D72680

Added: 
    llvm/lib/MC/MCParser/COFFMasmParser.cpp
    llvm/lib/MC/MCParser/MasmParser.cpp
    llvm/test/tools/llvm-ml/lit.local.cfg

Modified: 
    llvm/include/llvm/MC/MCAsmInfo.h
    llvm/include/llvm/MC/MCParser/AsmLexer.h
    llvm/include/llvm/MC/MCParser/MCAsmParser.h
    llvm/include/llvm/MC/MCStreamer.h
    llvm/include/llvm/MC/MCTargetOptions.h
    llvm/lib/MC/MCParser/AsmLexer.cpp
    llvm/lib/MC/MCParser/AsmParser.cpp
    llvm/lib/MC/MCParser/CMakeLists.txt
    llvm/lib/MC/MCParser/MCAsmParser.cpp
    llvm/lib/MC/MCTargetOptions.cpp
    llvm/lib/Target/X86/MCTargetDesc/X86MCAsmInfo.cpp
    llvm/lib/Target/X86/MCTargetDesc/X86MCAsmInfo.h
    llvm/lib/Target/X86/MCTargetDesc/X86MCTargetDesc.cpp
    llvm/test/tools/llvm-ml/basic.test
    llvm/tools/llvm-ml/llvm-ml.cpp
    llvm/utils/gn/secondary/llvm/lib/MC/MCParser/BUILD.gn

Removed: 
    


################################################################################
diff  --git a/llvm/include/llvm/MC/MCAsmInfo.h b/llvm/include/llvm/MC/MCAsmInfo.h
index 4ed1170f97ab..b4f7c350739a 100644
--- a/llvm/include/llvm/MC/MCAsmInfo.h
+++ b/llvm/include/llvm/MC/MCAsmInfo.h
@@ -156,6 +156,10 @@ class MCAsmInfo {
   /// Defaults to false.
   bool AllowAtInName = false;
 
+  /// This is true if the assembler allows $ @ ? characters at the start of
+  /// symbol names. Defaults to false.
+  bool AllowSymbolAtNameStart = false;
+
   /// If this is true, symbol names with invalid characters will be printed in
   /// quotes.
   bool SupportsQuotedNames = true;
@@ -537,6 +541,7 @@ class MCAsmInfo {
   const char *getCode64Directive() const { return Code64Directive; }
   unsigned getAssemblerDialect() const { return AssemblerDialect; }
   bool doesAllowAtInName() const { return AllowAtInName; }
+  bool doesAllowSymbolAtNameStart() const { return AllowSymbolAtNameStart; }
   bool supportsNameQuoting() const { return SupportsQuotedNames; }
 
   bool doesSupportDataRegionDirectives() const {

diff  --git a/llvm/include/llvm/MC/MCParser/AsmLexer.h b/llvm/include/llvm/MC/MCParser/AsmLexer.h
index b7294493b2f8..05b3695bc7a0 100644
--- a/llvm/include/llvm/MC/MCParser/AsmLexer.h
+++ b/llvm/include/llvm/MC/MCParser/AsmLexer.h
@@ -30,6 +30,7 @@ class AsmLexer : public MCAsmLexer {
   bool IsAtStartOfLine = true;
   bool IsAtStartOfStatement = true;
   bool IsPeeking = false;
+  bool EndStatementAtEOF = true;
 
 protected:
   /// LexToken - Read the next token and return its code.
@@ -41,7 +42,8 @@ class AsmLexer : public MCAsmLexer {
   AsmLexer &operator=(const AsmLexer &) = delete;
   ~AsmLexer() override;
 
-  void setBuffer(StringRef Buf, const char *ptr = nullptr);
+  void setBuffer(StringRef Buf, const char *ptr = nullptr,
+                 bool EndStatementAtEOF = true);
 
   StringRef LexUntilEndOfStatement() override;
 

diff  --git a/llvm/include/llvm/MC/MCParser/MCAsmParser.h b/llvm/include/llvm/MC/MCParser/MCAsmParser.h
index da5653ee71d3..9d9091306c13 100644
--- a/llvm/include/llvm/MC/MCParser/MCAsmParser.h
+++ b/llvm/include/llvm/MC/MCParser/MCAsmParser.h
@@ -250,6 +250,10 @@ class MCAsmParser {
   /// characters and return the string contents.
   virtual bool parseEscapedString(std::string &Data) = 0;
 
+  /// Parse an angle-bracket delimited string at the current position if one is
+  /// present, returning the string contents.
+  virtual bool parseAngleBracketString(std::string &Data) = 0;
+
   /// Skip to the end of the current statement, for error recovery.
   virtual void eatToEndOfStatement() = 0;
 
@@ -300,10 +304,14 @@ class MCAsmParser {
                                      SMLoc &EndLoc) = 0;
 };
 
-/// Create an MCAsmParser instance.
+/// Create an MCAsmParser instance for parsing assembly similar to gas syntax
 MCAsmParser *createMCAsmParser(SourceMgr &, MCContext &, MCStreamer &,
                                const MCAsmInfo &, unsigned CB = 0);
 
+/// Create an MCAsmParser instance for parsing Microsoft MASM-style assembly
+MCAsmParser *createMCMasmParser(SourceMgr &, MCContext &, MCStreamer &,
+                                const MCAsmInfo &, unsigned CB = 0);
+
 } // end namespace llvm
 
 #endif // LLVM_MC_MCPARSER_MCASMPARSER_H

diff  --git a/llvm/include/llvm/MC/MCStreamer.h b/llvm/include/llvm/MC/MCStreamer.h
index 989a553b660c..11f0bdfc4e59 100644
--- a/llvm/include/llvm/MC/MCStreamer.h
+++ b/llvm/include/llvm/MC/MCStreamer.h
@@ -399,7 +399,7 @@ class MCStreamer {
     --I;
     MCSectionSubPair NewSection = I->first;
 
-    if (OldSection != NewSection)
+    if (NewSection.first && OldSection != NewSection)
       ChangeSection(NewSection.first, NewSection.second);
     SectionStack.pop_back();
     return true;

diff  --git a/llvm/include/llvm/MC/MCTargetOptions.h b/llvm/include/llvm/MC/MCTargetOptions.h
index 51a5fc9aa26a..018c3374af3d 100644
--- a/llvm/include/llvm/MC/MCTargetOptions.h
+++ b/llvm/include/llvm/MC/MCTargetOptions.h
@@ -56,6 +56,7 @@ class MCTargetOptions {
   int DwarfVersion = 0;
 
   std::string ABIName;
+  std::string AssemblyLanguage;
   std::string SplitDwarfFile;
 
   /// Additional paths to search for `.include` directives when using the
@@ -68,6 +69,11 @@ class MCTargetOptions {
   /// textual name of the ABI that we want the backend to use, e.g. o32, or
   /// aapcs-linux.
   StringRef getABIName() const;
+
+  /// getAssemblyLanguage - If this returns a non-empty string this represents
+  /// the textual name of the assembly language that we will use for this
+  /// target, e.g. masm.
+  StringRef getAssemblyLanguage() const;
 };
 
 } // end namespace llvm

diff  --git a/llvm/lib/MC/MCParser/AsmLexer.cpp b/llvm/lib/MC/MCParser/AsmLexer.cpp
index 9155ae05d29d..5a571c7c0c0e 100644
--- a/llvm/lib/MC/MCParser/AsmLexer.cpp
+++ b/llvm/lib/MC/MCParser/AsmLexer.cpp
@@ -36,7 +36,8 @@ AsmLexer::AsmLexer(const MCAsmInfo &MAI) : MAI(MAI) {
 
 AsmLexer::~AsmLexer() = default;
 
-void AsmLexer::setBuffer(StringRef Buf, const char *ptr) {
+void AsmLexer::setBuffer(StringRef Buf, const char *ptr,
+                         bool EndStatementAtEOF) {
   CurBuf = Buf;
 
   if (ptr)
@@ -45,6 +46,7 @@ void AsmLexer::setBuffer(StringRef Buf, const char *ptr) {
     CurPtr = CurBuf.begin();
 
   TokStart = nullptr;
+  this->EndStatementAtEOF = EndStatementAtEOF;
 }
 
 /// ReturnError - Set the error to the specified string at the specified
@@ -584,7 +586,7 @@ AsmToken AsmLexer::LexToken() {
 
   // If we're missing a newline at EOF, make sure we still get an
   // EndOfStatement token before the Eof token.
-  if (CurChar == EOF && !IsAtStartOfStatement) {
+  if (CurChar == EOF && !IsAtStartOfStatement && EndStatementAtEOF) {
     IsAtStartOfLine = true;
     IsAtStartOfStatement = true;
     return AsmToken(AsmToken::EndOfStatement, StringRef(TokStart, 1));
@@ -594,15 +596,24 @@ AsmToken AsmLexer::LexToken() {
   IsAtStartOfStatement = false;
   switch (CurChar) {
   default:
-    // Handle identifier: [a-zA-Z_.][a-zA-Z0-9_$.@]*
-    if (isalpha(CurChar) || CurChar == '_' || CurChar == '.')
-      return LexIdentifier();
+    if (MAI.doesAllowSymbolAtNameStart()) {
+      // Handle Microsoft-style identifier: [a-zA-Z_$.@?][a-zA-Z0-9_$.@?]*
+      if (!isDigit(CurChar) &&
+          IsIdentifierChar(CurChar, MAI.doesAllowAtInName()))
+        return LexIdentifier();
+    } else {
+      // Handle identifier: [a-zA-Z_.][a-zA-Z0-9_$.@]*
+      if (isalpha(CurChar) || CurChar == '_' || CurChar == '.')
+        return LexIdentifier();
+    }
 
     // Unknown character, emit an error.
     return ReturnError(TokStart, "invalid character in input");
   case EOF:
-    IsAtStartOfLine = true;
-    IsAtStartOfStatement = true;
+    if (EndStatementAtEOF) {
+      IsAtStartOfLine = true;
+      IsAtStartOfStatement = true;
+    }
     return AsmToken(AsmToken::Eof, StringRef(TokStart, 0));
   case 0:
   case ' ':

diff  --git a/llvm/lib/MC/MCParser/AsmParser.cpp b/llvm/lib/MC/MCParser/AsmParser.cpp
index b7794cd4b75c..05c479abb69b 100644
--- a/llvm/lib/MC/MCParser/AsmParser.cpp
+++ b/llvm/lib/MC/MCParser/AsmParser.cpp
@@ -6,7 +6,7 @@
 //
 //===----------------------------------------------------------------------===//
 //
-// This class implements the parser for assembly files.
+// This class implements a parser for assembly files similar to gas syntax.
 //
 //===----------------------------------------------------------------------===//
 
@@ -74,9 +74,7 @@ using namespace llvm;
 
 MCAsmParserSemaCallback::~MCAsmParserSemaCallback() = default;
 
-static cl::opt<unsigned> AsmMacroMaxNestingDepth(
-     "asm-macro-max-nesting-depth", cl::init(20), cl::Hidden,
-     cl::desc("The maximum nesting depth allowed for assembly macros."));
+extern cl::opt<unsigned> AsmMacroMaxNestingDepth;
 
 namespace {
 
@@ -645,6 +643,7 @@ class AsmParser : public MCAsmParser {
   bool parseDirectiveElse(SMLoc DirectiveLoc); // ".else"
   bool parseDirectiveEndIf(SMLoc DirectiveLoc); // .endif
   bool parseEscapedString(std::string &Data) override;
+  bool parseAngleBracketString(std::string &Data) override;
 
   const MCExpr *applyModifierToExpr(const MCExpr *E,
                                     MCSymbolRefExpr::VariantKind Variant);
@@ -1365,7 +1364,7 @@ AsmParser::applyModifierToExpr(const MCExpr *E,
 /// implementation. GCC does not fully support this feature and so we will not
 /// support it.
 /// TODO: Adding single quote as a string.
-static bool isAltmacroString(SMLoc &StrLoc, SMLoc &EndLoc) {
+static bool isAngleBracketString(SMLoc &StrLoc, SMLoc &EndLoc) {
   assert((StrLoc.getPointer() != nullptr) &&
          "Argument to the function cannot be a NULL value");
   const char *CharPtr = StrLoc.getPointer();
@@ -1383,7 +1382,7 @@ static bool isAltmacroString(SMLoc &StrLoc, SMLoc &EndLoc) {
 }
 
 /// creating a string without the escape characters '!'.
-static std::string altMacroString(StringRef AltMacroStr) {
+static std::string angleBracketString(StringRef AltMacroStr) {
   std::string Res;
   for (size_t Pos = 0; Pos < AltMacroStr.size(); Pos++) {
     if (AltMacroStr[Pos] == '!')
@@ -2497,7 +2496,7 @@ bool AsmParser::expandMacro(raw_svector_ostream &OS, StringRef Body,
             // is considered altMacroString!!!
             else if (AltMacroMode && Token.getString().front() == '<' &&
                      Token.is(AsmToken::String)) {
-              OS << altMacroString(Token.getStringContents());
+              OS << angleBracketString(Token.getStringContents());
             }
             // We expect no quotes around the string's contents when
             // parsing for varargs.
@@ -2690,7 +2689,7 @@ bool AsmParser::parseMacroArguments(const MCAsmMacro *M,
                         StringRef(StrChar, EndChar - StrChar), Value);
       FA.Value.push_back(newToken);
     } else if (AltMacroMode && Lexer.is(AsmToken::Less) &&
-               isAltmacroString(StrLoc, EndLoc)) {
+               isAngleBracketString(StrLoc, EndLoc)) {
       const char *StrChar = StrLoc.getPointer();
       const char *EndChar = EndLoc.getPointer();
       jumpToLoc(EndLoc, CurBuffer);
@@ -2969,6 +2968,21 @@ bool AsmParser::parseEscapedString(std::string &Data) {
   return false;
 }
 
+bool AsmParser::parseAngleBracketString(std::string &Data) {
+  SMLoc EndLoc, StartLoc = getTok().getLoc();
+  if (isAngleBracketString(StartLoc, EndLoc)) {
+    const char *StartChar = StartLoc.getPointer() + 1;
+    const char *EndChar = EndLoc.getPointer() - 1;
+    jumpToLoc(EndLoc, CurBuffer);
+    /// Eat from '<' to '>'
+    Lex();
+
+    Data = angleBracketString(StringRef(StartChar, EndChar - StartChar));
+    return false;
+  }
+  return true;
+}
+
 /// parseDirectiveAscii:
 ///   ::= ( .ascii | .asciz | .string ) [ "string" ( , "string" )* ]
 bool AsmParser::parseDirectiveAscii(StringRef IDVal, bool ZeroTerminated) {

diff  --git a/llvm/lib/MC/MCParser/CMakeLists.txt b/llvm/lib/MC/MCParser/CMakeLists.txt
index 429670d39126..9165457c69b3 100644
--- a/llvm/lib/MC/MCParser/CMakeLists.txt
+++ b/llvm/lib/MC/MCParser/CMakeLists.txt
@@ -2,12 +2,14 @@ add_llvm_component_library(LLVMMCParser
   AsmLexer.cpp
   AsmParser.cpp
   COFFAsmParser.cpp
+  COFFMasmParser.cpp
   DarwinAsmParser.cpp
   ELFAsmParser.cpp
   MCAsmLexer.cpp
   MCAsmParser.cpp
   MCAsmParserExtension.cpp
   MCTargetAsmParser.cpp
+  MasmParser.cpp
   WasmAsmParser.cpp
 
   ADDITIONAL_HEADER_DIRS

diff  --git a/llvm/lib/MC/MCParser/COFFMasmParser.cpp b/llvm/lib/MC/MCParser/COFFMasmParser.cpp
new file mode 100644
index 000000000000..b7c48e92961b
--- /dev/null
+++ b/llvm/lib/MC/MCParser/COFFMasmParser.cpp
@@ -0,0 +1,386 @@
+//===- COFFMasmParser.cpp - COFF MASM Assembly Parser ---------------------===//
+//
+// 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/StringRef.h"
+#include "llvm/ADT/StringSwitch.h"
+#include "llvm/ADT/Triple.h"
+#include "llvm/ADT/Twine.h"
+#include "llvm/BinaryFormat/COFF.h"
+#include "llvm/MC/MCContext.h"
+#include "llvm/MC/MCDirectives.h"
+#include "llvm/MC/MCObjectFileInfo.h"
+#include "llvm/MC/MCParser/MCAsmLexer.h"
+#include "llvm/MC/MCParser/MCAsmParserExtension.h"
+#include "llvm/MC/MCParser/MCAsmParserUtils.h"
+#include "llvm/MC/MCParser/MCTargetAsmParser.h"
+#include "llvm/MC/MCRegisterInfo.h"
+#include "llvm/MC/MCSectionCOFF.h"
+#include "llvm/MC/MCStreamer.h"
+#include "llvm/MC/SectionKind.h"
+#include "llvm/Support/SMLoc.h"
+#include <cassert>
+#include <cstdint>
+#include <limits>
+#include <utility>
+
+using namespace llvm;
+
+namespace {
+
+class COFFMasmParser : public MCAsmParserExtension {
+  template <bool (COFFMasmParser::*HandlerMethod)(StringRef, SMLoc)>
+  void addDirectiveHandler(StringRef Directive) {
+    MCAsmParser::ExtensionDirectiveHandler Handler =
+        std::make_pair(this, HandleDirective<COFFMasmParser, HandlerMethod>);
+    getParser().addDirectiveHandler(Directive, Handler);
+  }
+
+  bool ParseSectionSwitch(StringRef Section, unsigned Characteristics,
+                          SectionKind Kind);
+
+  bool ParseSectionSwitch(StringRef Section, unsigned Characteristics,
+                          SectionKind Kind, StringRef COMDATSymName,
+                          COFF::COMDATType Type);
+
+  bool ParseDirectiveProc(StringRef, SMLoc);
+  bool ParseDirectiveEndProc(StringRef, SMLoc);
+  bool ParseDirectiveSegment(StringRef, SMLoc);
+  bool ParseDirectiveSegmentEnd(StringRef, SMLoc);
+  bool ParseDirectiveIncludelib(StringRef, SMLoc);
+
+  bool IgnoreDirective(StringRef, SMLoc) {
+    while (!getLexer().is(AsmToken::EndOfStatement)) {
+      Lex();
+    }
+    return false;
+  }
+
+  void Initialize(MCAsmParser &Parser) override {
+    // Call the base implementation.
+    MCAsmParserExtension::Initialize(Parser);
+
+    // x64 directives
+    // .allocstack
+    // .endprolog
+    // .pushframe
+    // .pushreg
+    // .savereg
+    // .savexmm128
+    // .setframe
+
+    // Code label directives
+    // label
+    // org
+
+    // Conditional control flow directives
+    // .break
+    // .continue
+    // .else
+    // .elseif
+    // .endif
+    // .endw
+    // .if
+    // .repeat
+    // .until
+    // .untilcxz
+    // .while
+
+    // Data allocation directives
+    // align
+    // byte/sbyte
+    // dword/sdword
+    // even
+    // fword
+    // qword
+    // real4
+    // real8
+    // real10
+    // tbyte
+    // word/sword
+
+    // Listing control directives
+    addDirectiveHandler<&COFFMasmParser::IgnoreDirective>(".cref");
+    addDirectiveHandler<&COFFMasmParser::IgnoreDirective>(".list");
+    addDirectiveHandler<&COFFMasmParser::IgnoreDirective>(".listall");
+    addDirectiveHandler<&COFFMasmParser::IgnoreDirective>(".listif");
+    addDirectiveHandler<&COFFMasmParser::IgnoreDirective>(".listmacro");
+    addDirectiveHandler<&COFFMasmParser::IgnoreDirective>(".listmacroall");
+    addDirectiveHandler<&COFFMasmParser::IgnoreDirective>(".nocref");
+    addDirectiveHandler<&COFFMasmParser::IgnoreDirective>(".nolist");
+    addDirectiveHandler<&COFFMasmParser::IgnoreDirective>(".nolistif");
+    addDirectiveHandler<&COFFMasmParser::IgnoreDirective>(".nolistmacro");
+    addDirectiveHandler<&COFFMasmParser::IgnoreDirective>("page");
+    addDirectiveHandler<&COFFMasmParser::IgnoreDirective>("subtitle");
+    addDirectiveHandler<&COFFMasmParser::IgnoreDirective>(".tfcond");
+    addDirectiveHandler<&COFFMasmParser::IgnoreDirective>("title");
+
+    // Macro directives
+    // endm
+    // exitm
+    // goto
+    // local
+    // macro
+    // purge
+
+    // Miscellaneous directives
+    // alias
+    // assume
+    // .fpo
+    addDirectiveHandler<&COFFMasmParser::ParseDirectiveIncludelib>(
+        "includelib");
+    // mmword
+    // option
+    // popcontext
+    // pushcontext
+    // .radix
+    // .safeseh
+    // xmmword
+    // ymmword
+
+    // Procedure directives
+    addDirectiveHandler<&COFFMasmParser::ParseDirectiveEndProc>("endp");
+    // invoke (32-bit only)
+    addDirectiveHandler<&COFFMasmParser::ParseDirectiveProc>("proc");
+    // proto
+
+    // Processor directives
+    addDirectiveHandler<&COFFMasmParser::IgnoreDirective>(".386");
+    addDirectiveHandler<&COFFMasmParser::IgnoreDirective>(".386P");
+    addDirectiveHandler<&COFFMasmParser::IgnoreDirective>(".387");
+    addDirectiveHandler<&COFFMasmParser::IgnoreDirective>(".486");
+    addDirectiveHandler<&COFFMasmParser::IgnoreDirective>(".486P");
+    addDirectiveHandler<&COFFMasmParser::IgnoreDirective>(".586");
+    addDirectiveHandler<&COFFMasmParser::IgnoreDirective>(".586P");
+    addDirectiveHandler<&COFFMasmParser::IgnoreDirective>(".686");
+    addDirectiveHandler<&COFFMasmParser::IgnoreDirective>(".686P");
+    addDirectiveHandler<&COFFMasmParser::IgnoreDirective>(".k3d");
+    addDirectiveHandler<&COFFMasmParser::IgnoreDirective>(".mmx");
+    addDirectiveHandler<&COFFMasmParser::IgnoreDirective>(".xmm");
+
+    // Repeat blocks directives
+    // for
+    // forc
+    // goto
+    // repeat
+    // while
+
+    // Scope directives
+    // comm
+    // externdef
+
+    // Segment directives
+    // .alpha (32-bit only, order segments alphabetically)
+    // .dosseg (32-bit only, order segments in DOS convention)
+    // .seq (32-bit only, order segments sequentially)
+    addDirectiveHandler<&COFFMasmParser::ParseDirectiveSegmentEnd>("ends");
+    // group (32-bit only)
+    addDirectiveHandler<&COFFMasmParser::ParseDirectiveSegment>("segment");
+
+    // Simplified segment directives
+    addDirectiveHandler<&COFFMasmParser::ParseSectionDirectiveCode>(".code");
+    // .const
+    addDirectiveHandler<
+        &COFFMasmParser::ParseSectionDirectiveInitializedData>(".data");
+    addDirectiveHandler<
+        &COFFMasmParser::ParseSectionDirectiveUninitializedData>(".data?");
+    // .exit
+    // .fardata
+    // .fardata?
+    addDirectiveHandler<&COFFMasmParser::IgnoreDirective>(".model");
+    // .stack
+    // .startup
+
+    // String directives, written <name> <directive> <params>
+    // catstr (equivalent to <name> TEXTEQU <params>)
+    // instr (equivalent to <name> = @InStr(<params>))
+    // sizestr (equivalent to <name> = @SizeStr(<params>))
+    // substr (equivalent to <name> TEXTEQU @SubStr(<params>))
+
+    // Structure and record directives
+    // ends
+    // record
+    // struct
+    // typedef
+    // union
+  }
+
+  bool ParseSectionDirectiveCode(StringRef, SMLoc) {
+    return ParseSectionSwitch(".text",
+                              COFF::IMAGE_SCN_CNT_CODE
+                            | COFF::IMAGE_SCN_MEM_EXECUTE
+                            | COFF::IMAGE_SCN_MEM_READ,
+                              SectionKind::getText());
+  }
+
+  bool ParseSectionDirectiveInitializedData(StringRef, SMLoc) {
+    return ParseSectionSwitch(".data",
+                              COFF::IMAGE_SCN_CNT_INITIALIZED_DATA
+                            | COFF::IMAGE_SCN_MEM_READ
+                            | COFF::IMAGE_SCN_MEM_WRITE,
+                              SectionKind::getData());
+  }
+
+  bool ParseSectionDirectiveUninitializedData(StringRef, SMLoc) {
+    return ParseSectionSwitch(".bss",
+                              COFF::IMAGE_SCN_CNT_UNINITIALIZED_DATA
+                            | COFF::IMAGE_SCN_MEM_READ
+                            | COFF::IMAGE_SCN_MEM_WRITE,
+                              SectionKind::getBSS());
+  }
+
+  StringRef CurrentProcedure;
+
+public:
+  COFFMasmParser() = default;
+};
+
+} // end anonymous namespace.
+
+static SectionKind computeSectionKind(unsigned Flags) {
+  if (Flags & COFF::IMAGE_SCN_MEM_EXECUTE)
+    return SectionKind::getText();
+  if (Flags & COFF::IMAGE_SCN_MEM_READ &&
+      (Flags & COFF::IMAGE_SCN_MEM_WRITE) == 0)
+    return SectionKind::getReadOnly();
+  return SectionKind::getData();
+}
+
+bool COFFMasmParser::ParseSectionSwitch(StringRef Section,
+                                        unsigned Characteristics,
+                                        SectionKind Kind) {
+  return ParseSectionSwitch(Section, Characteristics, Kind, "",
+                            (COFF::COMDATType)0);
+}
+
+bool COFFMasmParser::ParseSectionSwitch(StringRef Section,
+                                        unsigned Characteristics,
+                                        SectionKind Kind,
+                                        StringRef COMDATSymName,
+                                        COFF::COMDATType Type) {
+  if (getLexer().isNot(AsmToken::EndOfStatement))
+    return TokError("unexpected token in section switching directive");
+  Lex();
+
+  getStreamer().SwitchSection(getContext().getCOFFSection(
+      Section, Characteristics, Kind, COMDATSymName, Type));
+
+  return false;
+}
+
+bool COFFMasmParser::ParseDirectiveSegment(StringRef Directive, SMLoc Loc) {
+  StringRef SegmentName;
+  if (!getLexer().is(AsmToken::Identifier))
+    return TokError("expected identifier in directive");
+  SegmentName = getTok().getIdentifier();
+  Lex();
+
+  StringRef SectionName = SegmentName;
+  SmallVector<char, 247> SectionNameVector;
+  unsigned Flags = COFF::IMAGE_SCN_CNT_INITIALIZED_DATA |
+                   COFF::IMAGE_SCN_MEM_READ | COFF::IMAGE_SCN_MEM_WRITE;
+  if (SegmentName == "_TEXT" || SegmentName.startswith("_TEXT$")) {
+    if (SegmentName.size() == 5) {
+      SectionName = ".text";
+    } else {
+      SectionName =
+          (".text$" + SegmentName.substr(6)).toStringRef(SectionNameVector);
+    }
+    Flags = COFF::IMAGE_SCN_CNT_CODE | COFF::IMAGE_SCN_MEM_EXECUTE |
+            COFF::IMAGE_SCN_MEM_READ;
+  }
+  SectionKind Kind = computeSectionKind(Flags);
+  getStreamer().SwitchSection(getContext().getCOFFSection(
+      SectionName, Flags, Kind, "", (COFF::COMDATType)(0)));
+  return false;
+}
+
+/// ParseDirectiveSegmentEnd
+///  ::= identifier "ends"
+bool COFFMasmParser::ParseDirectiveSegmentEnd(StringRef Directive, SMLoc Loc) {
+  StringRef SegmentName;
+  if (!getLexer().is(AsmToken::Identifier))
+    return TokError("expected identifier in directive");
+  SegmentName = getTok().getIdentifier();
+
+  // Ignore; no action necessary.
+  Lex();
+  return false;
+}
+
+/// ParseDirectiveIncludelib
+///  ::= "includelib" identifier
+bool COFFMasmParser::ParseDirectiveIncludelib(StringRef Directive, SMLoc Loc) {
+  StringRef Lib;
+  if (getParser().parseIdentifier(Lib))
+    return TokError("expected identifier in includelib directive");
+
+  unsigned Flags = COFF::IMAGE_SCN_MEM_PRELOAD | COFF::IMAGE_SCN_MEM_16BIT;
+  SectionKind Kind = computeSectionKind(Flags);
+  getStreamer().PushSection();
+  getStreamer().SwitchSection(getContext().getCOFFSection(
+      ".drectve", Flags, Kind, "", (COFF::COMDATType)(0)));
+  getStreamer().emitBytes("/DEFAULTLIB:");
+  getStreamer().emitBytes(Lib);
+  getStreamer().emitBytes(" ");
+  getStreamer().PopSection();
+  return false;
+}
+
+/// ParseDirectiveProc
+/// TODO(epastor): Implement parameters and other attributes.
+///  ::= label "proc" [[distance]]
+///          statements
+///      label "endproc"
+bool COFFMasmParser::ParseDirectiveProc(StringRef Directive, SMLoc Loc) {
+  StringRef Label;
+  if (getParser().parseIdentifier(Label))
+    return Error(Loc, "expected identifier for procedure");
+  if (getLexer().is(AsmToken::Identifier)) {
+    StringRef nextVal = getTok().getString();
+    SMLoc nextLoc = getTok().getLoc();
+    if (nextVal.equals_lower("far")) {
+      // TODO(epastor): Handle far procedure definitions.
+      Lex();
+      return Error(nextLoc, "far procedure definitions not yet supported");
+    } else if (nextVal.equals_lower("near")) {
+      Lex();
+      nextVal = getTok().getString();
+      nextLoc = getTok().getLoc();
+    }
+  }
+  MCSymbol *Sym = getContext().getOrCreateSymbol(Label);
+
+  // Define symbol as simple function
+  getStreamer().BeginCOFFSymbolDef(Sym);
+  getStreamer().EmitCOFFSymbolStorageClass(2);
+  getStreamer().EmitCOFFSymbolType(0x20);
+  getStreamer().EndCOFFSymbolDef();
+
+  getStreamer().emitLabel(Sym, Loc);
+  CurrentProcedure = Label;
+  return false;
+}
+bool COFFMasmParser::ParseDirectiveEndProc(StringRef Directive, SMLoc Loc) {
+  StringRef Label;
+  SMLoc LabelLoc = getTok().getLoc();
+  if (getParser().parseIdentifier(Label))
+    return Error(LabelLoc, "expected identifier for procedure end");
+
+  if (CurrentProcedure.empty())
+    return Error(Loc, "endp outside of procedure block");
+  else if (CurrentProcedure != Label)
+    return Error(LabelLoc, "endp does not match current procedure '" +
+                               CurrentProcedure + "'");
+  return false;
+}
+
+namespace llvm {
+
+MCAsmParserExtension *createCOFFMasmParser() { return new COFFMasmParser; }
+
+} // end namespace llvm

diff  --git a/llvm/lib/MC/MCParser/MCAsmParser.cpp b/llvm/lib/MC/MCParser/MCAsmParser.cpp
index 41a1ee555d6f..c2fa7be56ad2 100644
--- a/llvm/lib/MC/MCParser/MCAsmParser.cpp
+++ b/llvm/lib/MC/MCParser/MCAsmParser.cpp
@@ -13,6 +13,7 @@
 #include "llvm/MC/MCParser/MCAsmLexer.h"
 #include "llvm/MC/MCParser/MCParsedAsmOperand.h"
 #include "llvm/MC/MCParser/MCTargetAsmParser.h"
+#include "llvm/Support/CommandLine.h"
 #include "llvm/Support/Debug.h"
 #include "llvm/Support/SMLoc.h"
 #include "llvm/Support/raw_ostream.h"
@@ -20,6 +21,10 @@
 
 using namespace llvm;
 
+cl::opt<unsigned> AsmMacroMaxNestingDepth(
+    "asm-macro-max-nesting-depth", cl::init(20), cl::Hidden,
+    cl::desc("The maximum nesting depth allowed for assembly macros."));
+
 MCAsmParser::MCAsmParser() {}
 
 MCAsmParser::~MCAsmParser() = default;

diff  --git a/llvm/lib/MC/MCParser/MasmParser.cpp b/llvm/lib/MC/MCParser/MasmParser.cpp
new file mode 100644
index 000000000000..71691cb9e3a2
--- /dev/null
+++ b/llvm/lib/MC/MCParser/MasmParser.cpp
@@ -0,0 +1,5566 @@
+//===- AsmParser.cpp - Parser for Assembly Files --------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+//
+// This class implements the parser for assembly files.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/ADT/APFloat.h"
+#include "llvm/ADT/APInt.h"
+#include "llvm/ADT/ArrayRef.h"
+#include "llvm/ADT/None.h"
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/ADT/SmallString.h"
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/ADT/StringExtras.h"
+#include "llvm/ADT/StringMap.h"
+#include "llvm/ADT/StringRef.h"
+#include "llvm/ADT/Twine.h"
+#include "llvm/BinaryFormat/Dwarf.h"
+#include "llvm/DebugInfo/CodeView/SymbolRecord.h"
+#include "llvm/MC/MCAsmInfo.h"
+#include "llvm/MC/MCCodeView.h"
+#include "llvm/MC/MCContext.h"
+#include "llvm/MC/MCDirectives.h"
+#include "llvm/MC/MCDwarf.h"
+#include "llvm/MC/MCExpr.h"
+#include "llvm/MC/MCInstPrinter.h"
+#include "llvm/MC/MCInstrDesc.h"
+#include "llvm/MC/MCInstrInfo.h"
+#include "llvm/MC/MCObjectFileInfo.h"
+#include "llvm/MC/MCParser/AsmCond.h"
+#include "llvm/MC/MCParser/AsmLexer.h"
+#include "llvm/MC/MCParser/MCAsmLexer.h"
+#include "llvm/MC/MCParser/MCAsmParser.h"
+#include "llvm/MC/MCParser/MCAsmParserExtension.h"
+#include "llvm/MC/MCParser/MCAsmParserUtils.h"
+#include "llvm/MC/MCParser/MCParsedAsmOperand.h"
+#include "llvm/MC/MCParser/MCTargetAsmParser.h"
+#include "llvm/MC/MCRegisterInfo.h"
+#include "llvm/MC/MCSection.h"
+#include "llvm/MC/MCStreamer.h"
+#include "llvm/MC/MCSymbol.h"
+#include "llvm/MC/MCTargetOptions.h"
+#include "llvm/MC/MCValue.h"
+#include "llvm/Support/Casting.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/MD5.h"
+#include "llvm/Support/MathExtras.h"
+#include "llvm/Support/MemoryBuffer.h"
+#include "llvm/Support/SMLoc.h"
+#include "llvm/Support/SourceMgr.h"
+#include "llvm/Support/raw_ostream.h"
+#include <algorithm>
+#include <cassert>
+#include <cctype>
+#include <climits>
+#include <cstddef>
+#include <cstdint>
+#include <deque>
+#include <memory>
+#include <sstream>
+#include <string>
+#include <tuple>
+#include <utility>
+#include <vector>
+
+using namespace llvm;
+
+extern cl::opt<unsigned> AsmMacroMaxNestingDepth;
+
+namespace {
+
+/// Helper types for tracking macro definitions.
+typedef std::vector<AsmToken> MCAsmMacroArgument;
+typedef std::vector<MCAsmMacroArgument> MCAsmMacroArguments;
+
+/// Helper class for storing information about an active macro
+/// instantiation.
+struct MacroInstantiation {
+  /// The location of the instantiation.
+  SMLoc InstantiationLoc;
+
+  /// The buffer where parsing should resume upon instantiation completion.
+  unsigned ExitBuffer;
+
+  /// The location where parsing should resume upon instantiation completion.
+  SMLoc ExitLoc;
+
+  /// The depth of TheCondStack at the start of the instantiation.
+  size_t CondStackDepth;
+};
+
+struct ParseStatementInfo {
+  /// The parsed operands from the last parsed statement.
+  SmallVector<std::unique_ptr<MCParsedAsmOperand>, 8> ParsedOperands;
+
+  /// The opcode from the last parsed instruction.
+  unsigned Opcode = ~0U;
+
+  /// Was there an error parsing the inline assembly?
+  bool ParseError = false;
+
+  SmallVectorImpl<AsmRewrite> *AsmRewrites = nullptr;
+
+  ParseStatementInfo() = delete;
+  ParseStatementInfo(SmallVectorImpl<AsmRewrite> *rewrites)
+      : AsmRewrites(rewrites) {}
+};
+
+/// The concrete assembly parser instance.
+// Note that this is a full MCAsmParser, not an MCAsmParserExtension!
+// It's a peer of AsmParser, not of COFFAsmParser, WasmAsmParser, etc.
+class MasmParser : public MCAsmParser {
+private:
+  AsmLexer Lexer;
+  MCContext &Ctx;
+  MCStreamer &Out;
+  const MCAsmInfo &MAI;
+  SourceMgr &SrcMgr;
+  SourceMgr::DiagHandlerTy SavedDiagHandler;
+  void *SavedDiagContext;
+  std::unique_ptr<MCAsmParserExtension> PlatformParser;
+
+  /// This is the current buffer index we're lexing from as managed by the
+  /// SourceMgr object.
+  unsigned CurBuffer;
+
+  AsmCond TheCondState;
+  std::vector<AsmCond> TheCondStack;
+
+  /// maps directive names to handler methods in parser
+  /// extensions. Extensions register themselves in this map by calling
+  /// addDirectiveHandler.
+  StringMap<ExtensionDirectiveHandler> ExtensionDirectiveMap;
+
+  /// maps assembly-time variable names to variables
+  struct Variable {
+    StringRef Name;
+    bool Redefinable = true;
+    bool IsText = false;
+    int64_t NumericValue = 0;
+    std::string TextValue;
+  };
+  StringMap<Variable> Variables;
+
+  /// Stack of active macro instantiations.
+  std::vector<MacroInstantiation*> ActiveMacros;
+
+  /// List of bodies of anonymous macros.
+  std::deque<MCAsmMacro> MacroLikeBodies;
+
+  /// Boolean tracking whether macro substitution is enabled.
+  unsigned MacrosEnabledFlag : 1;
+
+  /// Keeps track of how many .macro's have been instantiated.
+  unsigned NumOfMacroInstantiations;
+
+  /// The values from the last parsed cpp hash file line comment if any.
+  struct CppHashInfoTy {
+    StringRef Filename;
+    int64_t LineNumber;
+    SMLoc Loc;
+    unsigned Buf;
+    CppHashInfoTy() : Filename(), LineNumber(0), Loc(), Buf(0) {}
+  };
+  CppHashInfoTy CppHashInfo;
+
+  /// The filename from the first cpp hash file line comment, if any.
+  StringRef FirstCppHashFilename;
+
+  /// List of forward directional labels for diagnosis at the end.
+  SmallVector<std::tuple<SMLoc, CppHashInfoTy, MCSymbol *>, 4> DirLabels;
+
+  /// AssemblerDialect. ~OU means unset value and use value provided by MAI.
+  /// Defaults to 1U, meaning Intel.
+  unsigned AssemblerDialect = 1U;
+
+  /// is Darwin compatibility enabled?
+  bool IsDarwin = false;
+
+  /// Are we parsing ms-style inline assembly?
+  bool ParsingInlineAsm = false;
+
+  /// Did we already inform the user about inconsistent MD5 usage?
+  bool ReportedInconsistentMD5 = false;
+
+  // Is alt macro mode enabled.
+  bool AltMacroMode = false;
+
+public:
+  MasmParser(SourceMgr &SM, MCContext &Ctx, MCStreamer &Out,
+             const MCAsmInfo &MAI, unsigned CB);
+  MasmParser(const MasmParser &) = delete;
+  MasmParser &operator=(const MasmParser &) = delete;
+  ~MasmParser() override;
+
+  bool Run(bool NoInitialTextSection, bool NoFinalize = false) override;
+
+  void addDirectiveHandler(StringRef Directive,
+                           ExtensionDirectiveHandler Handler) override {
+    ExtensionDirectiveMap[Directive] = Handler;
+    if (DirectiveKindMap.find(Directive) == DirectiveKindMap.end()) {
+      DirectiveKindMap[Directive] = DK_HANDLER_DIRECTIVE;
+    }
+  }
+
+  void addAliasForDirective(StringRef Directive, StringRef Alias) override {
+    DirectiveKindMap[Directive] = DirectiveKindMap[Alias];
+  }
+
+  /// @name MCAsmParser Interface
+  /// {
+
+  SourceMgr &getSourceManager() override { return SrcMgr; }
+  MCAsmLexer &getLexer() override { return Lexer; }
+  MCContext &getContext() override { return Ctx; }
+  MCStreamer &getStreamer() override { return Out; }
+
+  CodeViewContext &getCVContext() { return Ctx.getCVContext(); }
+
+  unsigned getAssemblerDialect() override {
+    if (AssemblerDialect == ~0U)
+      return MAI.getAssemblerDialect();
+    else
+      return AssemblerDialect;
+  }
+  void setAssemblerDialect(unsigned i) override {
+    AssemblerDialect = i;
+  }
+
+  void Note(SMLoc L, const Twine &Msg, SMRange Range = None) override;
+  bool Warning(SMLoc L, const Twine &Msg, SMRange Range = None) override;
+  bool printError(SMLoc L, const Twine &Msg, SMRange Range = None) override;
+
+  const AsmToken &Lex() override;
+
+  void setParsingInlineAsm(bool V) override {
+    ParsingInlineAsm = V;
+    // When parsing MS inline asm, we must lex 0b1101 and 0ABCH as binary and
+    // hex integer literals.
+    Lexer.setLexMasmIntegers(V);
+  }
+  bool isParsingInlineAsm() override { return ParsingInlineAsm; }
+
+  bool parseMSInlineAsm(void *AsmLoc, std::string &AsmString,
+                        unsigned &NumOutputs, unsigned &NumInputs,
+                        SmallVectorImpl<std::pair<void *,bool>> &OpDecls,
+                        SmallVectorImpl<std::string> &Constraints,
+                        SmallVectorImpl<std::string> &Clobbers,
+                        const MCInstrInfo *MII, const MCInstPrinter *IP,
+                        MCAsmParserSemaCallback &SI) override;
+
+  bool parseExpression(const MCExpr *&Res);
+  bool parseExpression(const MCExpr *&Res, SMLoc &EndLoc) override;
+  bool parsePrimaryExpr(const MCExpr *&Res, SMLoc &EndLoc) override;
+  bool parseParenExpression(const MCExpr *&Res, SMLoc &EndLoc) override;
+  bool parseParenExprOfDepth(unsigned ParenDepth, const MCExpr *&Res,
+                             SMLoc &EndLoc) override;
+  bool parseAbsoluteExpression(int64_t &Res) override;
+
+  /// Parse a floating point expression using the float \p Semantics
+  /// and set \p Res to the value.
+  bool parseRealValue(const fltSemantics &Semantics, APInt &Res);
+
+  /// Parse an identifier or string (as a quoted identifier)
+  /// and set \p Res to the identifier contents.
+  bool parseIdentifier(StringRef &Res) override;
+  void eatToEndOfStatement() override;
+
+  bool checkForValidSection() override;
+
+  /// }
+
+private:
+  bool parseStatement(ParseStatementInfo &Info,
+                      MCAsmParserSemaCallback *SI);
+  bool parseCurlyBlockScope(SmallVectorImpl<AsmRewrite>& AsmStrRewrites);
+  bool parseCppHashLineFilenameComment(SMLoc L);
+
+  void checkForBadMacro(SMLoc DirectiveLoc, StringRef Name, StringRef Body,
+                        ArrayRef<MCAsmMacroParameter> Parameters);
+  bool expandMacro(raw_svector_ostream &OS, StringRef Body,
+                   ArrayRef<MCAsmMacroParameter> Parameters,
+                   ArrayRef<MCAsmMacroArgument> A, bool EnableAtPseudoVariable,
+                   SMLoc L);
+
+  /// Are macros enabled in the parser?
+  bool areMacrosEnabled() {return MacrosEnabledFlag;}
+
+  /// Control a flag in the parser that enables or disables macros.
+  void setMacrosEnabled(bool Flag) {MacrosEnabledFlag = Flag;}
+
+  /// Are we inside a macro instantiation?
+  bool isInsideMacroInstantiation() {return !ActiveMacros.empty();}
+
+  /// Handle entry to macro instantiation.
+  ///
+  /// \param M The macro.
+  /// \param NameLoc Instantiation location.
+  bool handleMacroEntry(const MCAsmMacro *M, SMLoc NameLoc);
+
+  /// Handle exit from macro instantiation.
+  void handleMacroExit();
+
+  /// Extract AsmTokens for a macro argument.
+  bool parseMacroArgument(MCAsmMacroArgument &MA, bool Vararg);
+
+  /// Parse all macro arguments for a given macro.
+  bool parseMacroArguments(const MCAsmMacro *M, MCAsmMacroArguments &A);
+
+  void printMacroInstantiations();
+  void printMessage(SMLoc Loc, SourceMgr::DiagKind Kind, const Twine &Msg,
+                    SMRange Range = None) const {
+    ArrayRef<SMRange> Ranges(Range);
+    SrcMgr.PrintMessage(Loc, Kind, Msg, Ranges);
+  }
+  static void DiagHandler(const SMDiagnostic &Diag, void *Context);
+
+  /// Should we emit DWARF describing this assembler source?  (Returns false if
+  /// the source has .file directives, which means we don't want to generate
+  /// info describing the assembler source itself.)
+  bool enabledGenDwarfForAssembly();
+
+  /// Enter the specified file. This returns true on failure.
+  bool enterIncludeFile(const std::string &Filename);
+
+  /// Process the specified file for the .incbin directive.
+  /// This returns true on failure.
+  bool processIncbinFile(const std::string &Filename, int64_t Skip = 0,
+                         const MCExpr *Count = nullptr, SMLoc Loc = SMLoc());
+
+  /// Reset the current lexer position to that given by \p Loc. The
+  /// current token is not set; clients should ensure Lex() is called
+  /// subsequently.
+  ///
+  /// \param InBuffer If not 0, should be the known buffer id that contains the
+  /// location.
+  void jumpToLoc(SMLoc Loc, unsigned InBuffer = 0);
+
+  /// Parse up to the end of statement and a return the contents from the
+  /// current token until the end of the statement; the current token on exit
+  /// will be either the EndOfStatement or EOF.
+  StringRef parseStringToEndOfStatement() override;
+
+  /// Parse until the end of a statement or a comma is encountered,
+  /// return the contents from the current token up to the end or comma.
+  StringRef parseStringToComma();
+
+  bool parseTextItem(std::string &Data);
+
+  unsigned getBinOpPrecedence(AsmToken::TokenKind K,
+                              MCBinaryExpr::Opcode &Kind);
+
+  bool parseBinOpRHS(unsigned Precedence, const MCExpr *&Res, SMLoc &EndLoc);
+  bool parseParenExpr(const MCExpr *&Res, SMLoc &EndLoc);
+  bool parseBracketExpr(const MCExpr *&Res, SMLoc &EndLoc);
+
+  bool parseRegisterOrRegisterNumber(int64_t &Register, SMLoc DirectiveLoc);
+
+  bool parseCVFunctionId(int64_t &FunctionId, StringRef DirectiveName);
+  bool parseCVFileId(int64_t &FileId, StringRef DirectiveName);
+
+  // Generic (target and platform independent) directive parsing.
+  enum DirectiveKind {
+    DK_NO_DIRECTIVE, // Placeholder
+    DK_HANDLER_DIRECTIVE,
+    DK_ASSIGN,
+    DK_EQU,
+    DK_TEXTEQU,
+    DK_ASCII,
+    DK_ASCIZ,
+    DK_STRING,
+    DK_BYTE,
+    DK_SBYTE,
+    DK_WORD,
+    DK_SWORD,
+    DK_DWORD,
+    DK_SDWORD,
+    DK_FWORD,
+    DK_QWORD,
+    DK_SQWORD,
+    DK_DB,
+    DK_DD,
+    DK_DQ,
+    DK_DW,
+    DK_REAL4,
+    DK_REAL8,
+    DK_ALIGN,
+    DK_ORG,
+    DK_ENDR,
+    DK_EXTERN,
+    DK_PUBLIC,
+    DK_COMM,
+    DK_COMMENT,
+    DK_INCLUDE,
+    DK_REPT,
+    DK_IRP,
+    DK_IRPC,
+    DK_IF,
+    DK_IFE,
+    DK_IFB,
+    DK_IFNB,
+    DK_IFDEF,
+    DK_IFNDEF,
+    DK_IFDIF,
+    DK_IFDIFI,
+    DK_IFIDN,
+    DK_IFIDNI,
+    DK_ELSEIF,
+    DK_ELSEIFE,
+    DK_ELSEIFB,
+    DK_ELSEIFNB,
+    DK_ELSEIFDEF,
+    DK_ELSEIFNDEF,
+    DK_ELSEIFDIF,
+    DK_ELSEIFDIFI,
+    DK_ELSEIFIDN,
+    DK_ELSEIFIDNI,
+    DK_ELSE,
+    DK_ENDIF,
+    DK_FILE,
+    DK_LINE,
+    DK_LOC,
+    DK_STABS,
+    DK_CV_FILE,
+    DK_CV_FUNC_ID,
+    DK_CV_INLINE_SITE_ID,
+    DK_CV_LOC,
+    DK_CV_LINETABLE,
+    DK_CV_INLINE_LINETABLE,
+    DK_CV_DEF_RANGE,
+    DK_CV_STRINGTABLE,
+    DK_CV_STRING,
+    DK_CV_FILECHECKSUMS,
+    DK_CV_FILECHECKSUM_OFFSET,
+    DK_CV_FPO_DATA,
+    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,
+    DK_CFI_REMEMBER_STATE,
+    DK_CFI_RESTORE_STATE,
+    DK_CFI_SAME_VALUE,
+    DK_CFI_RESTORE,
+    DK_CFI_ESCAPE,
+    DK_CFI_RETURN_COLUMN,
+    DK_CFI_SIGNAL_FRAME,
+    DK_CFI_UNDEFINED,
+    DK_CFI_REGISTER,
+    DK_CFI_WINDOW_SAVE,
+    DK_CFI_B_KEY_FRAME,
+    DK_ALTMACRO,
+    DK_NOALTMACRO,
+    DK_MACRO,
+    DK_EXITM,
+    DK_ENDM,
+    DK_PURGEM,
+    DK_ERR,
+    DK_ERRB,
+    DK_ERRNB,
+    DK_ERRDEF,
+    DK_ERRNDEF,
+    DK_ERRDIF,
+    DK_ERRDIFI,
+    DK_ERRIDN,
+    DK_ERRIDNI,
+    DK_ERRE,
+    DK_ERRNZ,
+    DK_ECHO,
+    DK_END
+  };
+
+  /// Maps directive name --> DirectiveKind enum, for
+  /// directives parsed by this class.
+  StringMap<DirectiveKind> DirectiveKindMap;
+
+  // Codeview def_range type parsing.
+  enum CVDefRangeType {
+    CVDR_DEFRANGE = 0, // Placeholder
+    CVDR_DEFRANGE_REGISTER,
+    CVDR_DEFRANGE_FRAMEPOINTER_REL,
+    CVDR_DEFRANGE_SUBFIELD_REGISTER,
+    CVDR_DEFRANGE_REGISTER_REL
+  };
+
+  /// Maps Codeview def_range types --> CVDefRangeType enum, for
+  /// Codeview def_range types parsed by this class.
+  StringMap<CVDefRangeType> CVDefRangeTypeMap;
+
+  // ".ascii", ".asciz", ".string"
+  bool parseDirectiveAscii(StringRef IDVal, bool ZeroTerminated);
+  bool parseDirectiveValue(StringRef IDVal,
+                           unsigned Size);       // "byte", "word", ...
+  bool parseDirectiveRealValue(StringRef IDVal,
+                               const fltSemantics &);  // "real4", ...
+
+  // "=", "equ", "textequ"
+  bool parseDirectiveEquate(StringRef IDVal, StringRef Name,
+                            DirectiveKind DirKind);
+
+  bool parseDirectiveOrg(); // ".org"
+  bool parseDirectiveAlign();  // "align"
+
+  // ".file", ".line", ".loc", ".stabs"
+  bool parseDirectiveFile(SMLoc DirectiveLoc);
+  bool parseDirectiveLine();
+  bool parseDirectiveLoc();
+  bool parseDirectiveStabs();
+
+  // ".cv_file", ".cv_func_id", ".cv_inline_site_id", ".cv_loc", ".cv_linetable",
+  // ".cv_inline_linetable", ".cv_def_range", ".cv_string"
+  bool parseDirectiveCVFile();
+  bool parseDirectiveCVFuncId();
+  bool parseDirectiveCVInlineSiteId();
+  bool parseDirectiveCVLoc();
+  bool parseDirectiveCVLinetable();
+  bool parseDirectiveCVInlineLinetable();
+  bool parseDirectiveCVDefRange();
+  bool parseDirectiveCVString();
+  bool parseDirectiveCVStringTable();
+  bool parseDirectiveCVFileChecksums();
+  bool parseDirectiveCVFileChecksumOffset();
+  bool parseDirectiveCVFPOData();
+
+  // .cfi directives
+  bool parseDirectiveCFIRegister(SMLoc DirectiveLoc);
+  bool parseDirectiveCFIWindowSave();
+  bool parseDirectiveCFISections();
+  bool parseDirectiveCFIStartProc();
+  bool parseDirectiveCFIEndProc();
+  bool parseDirectiveCFIDefCfaOffset();
+  bool parseDirectiveCFIDefCfa(SMLoc DirectiveLoc);
+  bool parseDirectiveCFIAdjustCfaOffset();
+  bool parseDirectiveCFIDefCfaRegister(SMLoc DirectiveLoc);
+  bool parseDirectiveCFIOffset(SMLoc DirectiveLoc);
+  bool parseDirectiveCFIRelOffset(SMLoc DirectiveLoc);
+  bool parseDirectiveCFIPersonalityOrLsda(bool IsPersonality);
+  bool parseDirectiveCFIRememberState();
+  bool parseDirectiveCFIRestoreState();
+  bool parseDirectiveCFISameValue(SMLoc DirectiveLoc);
+  bool parseDirectiveCFIRestore(SMLoc DirectiveLoc);
+  bool parseDirectiveCFIEscape();
+  bool parseDirectiveCFIReturnColumn(SMLoc DirectiveLoc);
+  bool parseDirectiveCFISignalFrame();
+  bool parseDirectiveCFIUndefined(SMLoc DirectiveLoc);
+
+  // macro directives
+  bool parseDirectivePurgeMacro(SMLoc DirectiveLoc);
+  bool parseDirectiveExitMacro(StringRef Directive);
+  bool parseDirectiveEndMacro(StringRef Directive);
+  bool parseDirectiveMacro(SMLoc DirectiveLoc);
+  bool parseDirectiveMacrosOnOff(StringRef Directive);
+  // alternate macro mode directives
+  bool parseDirectiveAltmacro(StringRef Directive);
+
+  /// Parse a directive like ".globl" which
+  /// accepts a single symbol (which should be a label or an external).
+  bool parseDirectiveSymbolAttribute(MCSymbolAttr Attr);
+
+  bool parseDirectiveComm(bool IsLocal); // ".comm" and ".lcomm"
+
+  bool parseDirectiveComment(SMLoc DirectiveLoc); // "comment"
+
+  bool parseDirectiveInclude(); // "include"
+
+  // "if" or "ife"
+  bool parseDirectiveIf(SMLoc DirectiveLoc, DirectiveKind DirKind);
+  // "ifb" or "ifnb", depending on ExpectBlank.
+  bool parseDirectiveIfb(SMLoc DirectiveLoc, bool ExpectBlank);
+  // "ifidn", "ifdif", "ifidni", or "ifdifi", depending on ExpectEqual and
+  // CaseInsensitive.
+  bool parseDirectiveIfidn(SMLoc DirectiveLoc, bool ExpectEqual,
+                           bool CaseInsensitive);
+  // "ifdef" or "ifndef", depending on expect_defined
+  bool parseDirectiveIfdef(SMLoc DirectiveLoc, bool expect_defined);
+  // "elseif" or "elseife"
+  bool parseDirectiveElseIf(SMLoc DirectiveLoc, DirectiveKind DirKind);
+  // "elseifb" or "elseifnb", depending on ExpectBlank.
+  bool parseDirectiveElseIfb(SMLoc DirectiveLoc, bool ExpectBlank);
+  // ".elseifdef" or ".elseifndef", depending on expect_defined
+  bool parseDirectiveElseIfdef(SMLoc DirectiveLoc, bool expect_defined);
+  // "elseifidn", "elseifdif", "elseifidni", or "elseifdifi", depending on
+  // ExpectEqual and CaseInsensitive.
+  bool parseDirectiveElseIfidn(SMLoc DirectiveLoc, bool ExpectEqual,
+                               bool CaseInsensitive);
+  bool parseDirectiveElse(SMLoc DirectiveLoc);   // "else"
+  bool parseDirectiveEndIf(SMLoc DirectiveLoc);  // "endif"
+  bool parseEscapedString(std::string &Data) override;
+  bool parseAngleBracketString(std::string &Data) override;
+
+  // Macro-like directives
+  MCAsmMacro *parseMacroLikeBody(SMLoc DirectiveLoc);
+  void instantiateMacroLikeBody(MCAsmMacro *M, SMLoc DirectiveLoc,
+                                raw_svector_ostream &OS);
+  bool parseDirectiveRept(SMLoc DirectiveLoc, StringRef Directive);
+  bool parseDirectiveIrp(SMLoc DirectiveLoc);  // ".irp"
+  bool parseDirectiveIrpc(SMLoc DirectiveLoc); // ".irpc"
+  bool parseDirectiveEndr(SMLoc DirectiveLoc); // ".endr"
+
+  // "_emit" or "__emit"
+  bool parseDirectiveMSEmit(SMLoc DirectiveLoc, ParseStatementInfo &Info,
+                            size_t Len);
+
+  // "align"
+  bool parseDirectiveMSAlign(SMLoc DirectiveLoc, ParseStatementInfo &Info);
+
+  // "end"
+  bool parseDirectiveEnd(SMLoc DirectiveLoc);
+
+  // ".err"
+  bool parseDirectiveError(SMLoc DirectiveLoc);
+  // ".errb" or ".errnb", depending on ExpectBlank.
+  bool parseDirectiveErrorIfb(SMLoc DirectiveLoc, bool ExpectBlank);
+  // ".errdef" or ".errndef", depending on ExpectBlank.
+  bool parseDirectiveErrorIfdef(SMLoc DirectiveLoc, bool ExpectDefined);
+  // ".erridn", ".errdif", ".erridni", or ".errdifi", depending on ExpectEqual
+  // and CaseInsensitive.
+  bool parseDirectiveErrorIfidn(SMLoc DirectiveLoc, bool ExpectEqual,
+                                bool CaseInsensitive);
+  // ".erre" or ".errnz", depending on ExpectZero.
+  bool parseDirectiveErrorIfe(SMLoc DirectiveLoc, bool ExpectZero);
+
+  // "echo"
+  bool parseDirectiveEcho();
+
+  void initializeDirectiveKindMap();
+  void initializeCVDefRangeTypeMap();
+};
+
+} // end anonymous namespace
+
+namespace llvm {
+
+extern MCAsmParserExtension *createCOFFMasmParser();
+
+} // end namespace llvm
+
+enum { DEFAULT_ADDRSPACE = 0 };
+
+MasmParser::MasmParser(SourceMgr &SM, MCContext &Ctx, MCStreamer &Out,
+                       const MCAsmInfo &MAI, unsigned CB = 0)
+    : Lexer(MAI), Ctx(Ctx), Out(Out), MAI(MAI), SrcMgr(SM),
+      CurBuffer(CB ? CB : SM.getMainFileID()), MacrosEnabledFlag(true) {
+  HadError = false;
+  // Save the old handler.
+  SavedDiagHandler = SrcMgr.getDiagHandler();
+  SavedDiagContext = SrcMgr.getDiagContext();
+  // Set our own handler which calls the saved handler.
+  SrcMgr.setDiagHandler(DiagHandler, this);
+  Lexer.setBuffer(SrcMgr.getMemoryBuffer(CurBuffer)->getBuffer());
+
+  // Initialize the platform / file format parser.
+  switch (Ctx.getObjectFileInfo()->getObjectFileType()) {
+  case MCObjectFileInfo::IsCOFF:
+    PlatformParser.reset(createCOFFMasmParser());
+    break;
+  default:
+    report_fatal_error("llvm-ml currently supports only COFF output.");
+    break;
+  }
+
+  initializeDirectiveKindMap();
+  PlatformParser->Initialize(*this);
+  initializeCVDefRangeTypeMap();
+
+  NumOfMacroInstantiations = 0;
+}
+
+MasmParser::~MasmParser() {
+  assert((HadError || ActiveMacros.empty()) &&
+         "Unexpected active macro instantiation!");
+
+  // Restore the saved diagnostics handler and context for use during
+  // finalization.
+  SrcMgr.setDiagHandler(SavedDiagHandler, SavedDiagContext);
+}
+
+void MasmParser::printMacroInstantiations() {
+  // Print the active macro instantiation stack.
+  for (std::vector<MacroInstantiation *>::const_reverse_iterator
+           it = ActiveMacros.rbegin(),
+           ie = ActiveMacros.rend();
+       it != ie; ++it)
+    printMessage((*it)->InstantiationLoc, SourceMgr::DK_Note,
+                 "while in macro instantiation");
+}
+
+void MasmParser::Note(SMLoc L, const Twine &Msg, SMRange Range) {
+  printPendingErrors();
+  printMessage(L, SourceMgr::DK_Note, Msg, Range);
+  printMacroInstantiations();
+}
+
+bool MasmParser::Warning(SMLoc L, const Twine &Msg, SMRange Range) {
+  if (getTargetParser().getTargetOptions().MCNoWarn)
+    return false;
+  if (getTargetParser().getTargetOptions().MCFatalWarnings)
+    return Error(L, Msg, Range);
+  printMessage(L, SourceMgr::DK_Warning, Msg, Range);
+  printMacroInstantiations();
+  return false;
+}
+
+bool MasmParser::printError(SMLoc L, const Twine &Msg, SMRange Range) {
+  HadError = true;
+  printMessage(L, SourceMgr::DK_Error, Msg, Range);
+  printMacroInstantiations();
+  return true;
+}
+
+bool MasmParser::enterIncludeFile(const std::string &Filename) {
+  std::string IncludedFile;
+  unsigned NewBuf =
+      SrcMgr.AddIncludeFile(Filename, Lexer.getLoc(), IncludedFile);
+  if (!NewBuf)
+    return true;
+
+  CurBuffer = NewBuf;
+  Lexer.setBuffer(SrcMgr.getMemoryBuffer(CurBuffer)->getBuffer());
+  return false;
+}
+
+/// Process the specified .incbin file by searching for it in the include paths
+/// then just emitting the byte contents of the file to the streamer. This
+/// returns true on failure.
+bool MasmParser::processIncbinFile(const std::string &Filename, int64_t Skip,
+                                   const MCExpr *Count, SMLoc Loc) {
+  std::string IncludedFile;
+  unsigned NewBuf =
+      SrcMgr.AddIncludeFile(Filename, Lexer.getLoc(), IncludedFile);
+  if (!NewBuf)
+    return true;
+
+  // Pick up the bytes from the file and emit them.
+  StringRef Bytes = SrcMgr.getMemoryBuffer(NewBuf)->getBuffer();
+  Bytes = Bytes.drop_front(Skip);
+  if (Count) {
+    int64_t Res;
+    if (!Count->evaluateAsAbsolute(Res, getStreamer().getAssemblerPtr()))
+      return Error(Loc, "expected absolute expression");
+    if (Res < 0)
+      return Warning(Loc, "negative count has no effect");
+    Bytes = Bytes.take_front(Res);
+  }
+  getStreamer().emitBytes(Bytes);
+  return false;
+}
+
+void MasmParser::jumpToLoc(SMLoc Loc, unsigned InBuffer) {
+  CurBuffer = InBuffer ? InBuffer : SrcMgr.FindBufferContainingLoc(Loc);
+  Lexer.setBuffer(SrcMgr.getMemoryBuffer(CurBuffer)->getBuffer(),
+                  Loc.getPointer());
+}
+
+const AsmToken &MasmParser::Lex() {
+  if (Lexer.getTok().is(AsmToken::Error))
+    Error(Lexer.getErrLoc(), Lexer.getErr());
+
+  // if it's a end of statement with a comment in it
+  if (getTok().is(AsmToken::EndOfStatement)) {
+    // if this is a line comment output it.
+    if (!getTok().getString().empty() && getTok().getString().front() != '\n' &&
+        getTok().getString().front() != '\r' && MAI.preserveAsmComments())
+      Out.addExplicitComment(Twine(getTok().getString()));
+  }
+
+  const AsmToken *tok = &Lexer.Lex();
+
+  while (tok->is(AsmToken::Identifier)) {
+    auto it = Variables.find(tok->getIdentifier());
+    if (it != Variables.end() && it->second.IsText) {
+      std::unique_ptr<MemoryBuffer> Instantiation =
+          MemoryBuffer::getMemBufferCopy(it->second.TextValue,
+                                         "<instantiation>");
+
+      // Jump to the macro instantiation and prime the lexer.
+      CurBuffer = SrcMgr.AddNewSourceBuffer(std::move(Instantiation),
+                                            getTok().getEndLoc());
+      Lexer.setBuffer(SrcMgr.getMemoryBuffer(CurBuffer)->getBuffer(), nullptr,
+                      /*EndStatementAtEOF=*/false);
+      tok = &Lexer.Lex();
+    } else {
+      break;
+    }
+  }
+
+  // Parse comments here to be deferred until end of next statement.
+  while (tok->is(AsmToken::Comment)) {
+    if (MAI.preserveAsmComments())
+      Out.addExplicitComment(Twine(tok->getString()));
+    tok = &Lexer.Lex();
+  }
+
+  if (tok->is(AsmToken::Eof)) {
+    // If this is the end of an included file, pop the parent file off the
+    // include stack.
+    SMLoc ParentIncludeLoc = SrcMgr.getParentIncludeLoc(CurBuffer);
+    if (ParentIncludeLoc != SMLoc()) {
+      jumpToLoc(ParentIncludeLoc);
+      return Lex();
+    }
+  }
+
+  return *tok;
+}
+
+bool MasmParser::enabledGenDwarfForAssembly() {
+  // Check whether the user specified -g.
+  if (!getContext().getGenDwarfForAssembly())
+    return false;
+  // If we haven't encountered any .file directives (which would imply that
+  // the assembler source was produced with debug info already) then emit one
+  // describing the assembler source file itself.
+  if (getContext().getGenDwarfFileNumber() == 0) {
+    // Use the first #line directive for this, if any. It's preprocessed, so
+    // there is no checksum, and of course no source directive.
+    if (!FirstCppHashFilename.empty())
+      getContext().setMCLineTableRootFile(/*CUID=*/0,
+                                          getContext().getCompilationDir(),
+                                          FirstCppHashFilename,
+                                          /*Cksum=*/None, /*Source=*/None);
+    const MCDwarfFile &RootFile =
+        getContext().getMCDwarfLineTable(/*CUID=*/0).getRootFile();
+    getContext().setGenDwarfFileNumber(getStreamer().emitDwarfFileDirective(
+        /*CUID=*/0, getContext().getCompilationDir(), RootFile.Name,
+        RootFile.Checksum, RootFile.Source));
+  }
+  return true;
+}
+
+bool MasmParser::Run(bool NoInitialTextSection, bool NoFinalize) {
+  // Create the initial section, if requested.
+  if (!NoInitialTextSection)
+    Out.InitSections(false);
+
+  // Prime the lexer.
+  Lex();
+
+  HadError = false;
+  AsmCond StartingCondState = TheCondState;
+  SmallVector<AsmRewrite, 4> AsmStrRewrites;
+
+  // If we are generating dwarf for assembly source files save the initial text
+  // section.  (Don't use enabledGenDwarfForAssembly() here, as we aren't
+  // emitting any actual debug info yet and haven't had a chance to parse any
+  // embedded .file directives.)
+  if (getContext().getGenDwarfForAssembly()) {
+    MCSection *Sec = getStreamer().getCurrentSectionOnly();
+    if (!Sec->getBeginSymbol()) {
+      MCSymbol *SectionStartSym = getContext().createTempSymbol();
+      getStreamer().emitLabel(SectionStartSym);
+      Sec->setBeginSymbol(SectionStartSym);
+    }
+    bool InsertResult = getContext().addGenDwarfSection(Sec);
+    assert(InsertResult && ".text section should not have debug info yet");
+    (void)InsertResult;
+  }
+
+  // While we have input, parse each statement.
+  while (Lexer.isNot(AsmToken::Eof)) {
+    ParseStatementInfo Info(&AsmStrRewrites);
+    bool Parsed = parseStatement(Info, nullptr);
+
+    // If we have a Lexer Error we are on an Error Token. Load in Lexer Error
+    // for printing ErrMsg via Lex() only if no (presumably better) parser error
+    // exists.
+    if (Parsed && !hasPendingError() && Lexer.getTok().is(AsmToken::Error)) {
+      Lex();
+    }
+
+    // parseStatement returned true so may need to emit an error.
+    printPendingErrors();
+
+    // Skipping to the next line if needed.
+    if (Parsed && !getLexer().isAtStartOfStatement())
+      eatToEndOfStatement();
+  }
+
+  getTargetParser().onEndOfFile();
+  printPendingErrors();
+
+  // All errors should have been emitted.
+  assert(!hasPendingError() && "unexpected error from parseStatement");
+
+  getTargetParser().flushPendingInstructions(getStreamer());
+
+  if (TheCondState.TheCond != StartingCondState.TheCond ||
+      TheCondState.Ignore != StartingCondState.Ignore)
+    printError(getTok().getLoc(), "unmatched .ifs or .elses");
+  // Check to see there are no empty DwarfFile slots.
+  const auto &LineTables = getContext().getMCDwarfLineTables();
+  if (!LineTables.empty()) {
+    unsigned Index = 0;
+    for (const auto &File : LineTables.begin()->second.getMCDwarfFiles()) {
+      if (File.Name.empty() && Index != 0)
+        printError(getTok().getLoc(), "unassigned file number: " +
+                                          Twine(Index) +
+                                          " for .file directives");
+      ++Index;
+    }
+  }
+
+  // Check to see that all assembler local symbols were actually defined.
+  // Targets that don't do subsections via symbols may not want this, though,
+  // so conservatively exclude them. Only do this if we're finalizing, though,
+  // as otherwise we won't necessarilly have seen everything yet.
+  if (!NoFinalize) {
+    if (MAI.hasSubsectionsViaSymbols()) {
+      for (const auto &TableEntry : getContext().getSymbols()) {
+        MCSymbol *Sym = TableEntry.getValue();
+        // Variable symbols may not be marked as defined, so check those
+        // explicitly. If we know it's a variable, we have a definition for
+        // the purposes of this check.
+        if (Sym->isTemporary() && !Sym->isVariable() && !Sym->isDefined())
+          // FIXME: We would really like to refer back to where the symbol was
+          // first referenced for a source location. We need to add something
+          // to track that. Currently, we just point to the end of the file.
+          printError(getTok().getLoc(), "assembler local symbol '" +
+                                            Sym->getName() + "' not defined");
+      }
+    }
+
+    // Temporary symbols like the ones for directional jumps don't go in the
+    // symbol table. They also need to be diagnosed in all (final) cases.
+    for (std::tuple<SMLoc, CppHashInfoTy, MCSymbol *> &LocSym : DirLabels) {
+      if (std::get<2>(LocSym)->isUndefined()) {
+        // Reset the state of any "# line file" directives we've seen to the
+        // context as it was at the diagnostic site.
+        CppHashInfo = std::get<1>(LocSym);
+        printError(std::get<0>(LocSym), "directional label undefined");
+      }
+    }
+  }
+
+  // Finalize the output stream if there are no errors and if the client wants
+  // us to.
+  if (!HadError && !NoFinalize)
+    Out.Finish();
+
+  return HadError || getContext().hadError();
+}
+
+bool MasmParser::checkForValidSection() {
+  if (!ParsingInlineAsm && !getStreamer().getCurrentSectionOnly()) {
+    Out.InitSections(false);
+    return Error(getTok().getLoc(),
+                 "expected section directive before assembly directive");
+  }
+  return false;
+}
+
+/// Throw away the rest of the line for testing purposes.
+void MasmParser::eatToEndOfStatement() {
+  while (Lexer.isNot(AsmToken::EndOfStatement) && Lexer.isNot(AsmToken::Eof))
+    Lexer.Lex();
+
+  // Eat EOL.
+  if (Lexer.is(AsmToken::EndOfStatement))
+    Lexer.Lex();
+}
+
+StringRef MasmParser::parseStringToEndOfStatement() {
+  const char *Start = getTok().getLoc().getPointer();
+
+  while (Lexer.isNot(AsmToken::EndOfStatement) && Lexer.isNot(AsmToken::Eof))
+    Lexer.Lex();
+
+  const char *End = getTok().getLoc().getPointer();
+  return StringRef(Start, End - Start);
+}
+
+StringRef MasmParser::parseStringToComma() {
+  const char *Start = getTok().getLoc().getPointer();
+
+  while (Lexer.isNot(AsmToken::EndOfStatement) &&
+         Lexer.isNot(AsmToken::Comma) && Lexer.isNot(AsmToken::Eof))
+    Lexer.Lex();
+
+  const char *End = getTok().getLoc().getPointer();
+  return StringRef(Start, End - Start);
+}
+
+/// Parse a paren expression and return it.
+/// NOTE: This assumes the leading '(' has already been consumed.
+///
+/// parenexpr ::= expr)
+///
+bool MasmParser::parseParenExpr(const MCExpr *&Res, SMLoc &EndLoc) {
+  if (parseExpression(Res))
+    return true;
+  if (Lexer.isNot(AsmToken::RParen))
+    return TokError("expected ')' in parentheses expression");
+  EndLoc = Lexer.getTok().getEndLoc();
+  Lex();
+  return false;
+}
+
+/// Parse a bracket expression and return it.
+/// NOTE: This assumes the leading '[' has already been consumed.
+///
+/// bracketexpr ::= expr]
+///
+bool MasmParser::parseBracketExpr(const MCExpr *&Res, SMLoc &EndLoc) {
+  if (parseExpression(Res))
+    return true;
+  EndLoc = getTok().getEndLoc();
+  if (parseToken(AsmToken::RBrac, "expected ']' in brackets expression"))
+    return true;
+  return false;
+}
+
+/// Parse a primary expression and return it.
+///  primaryexpr ::= (parenexpr
+///  primaryexpr ::= symbol
+///  primaryexpr ::= number
+///  primaryexpr ::= '.'
+///  primaryexpr ::= ~,+,- primaryexpr
+bool MasmParser::parsePrimaryExpr(const MCExpr *&Res, SMLoc &EndLoc) {
+  SMLoc FirstTokenLoc = getLexer().getLoc();
+  AsmToken::TokenKind FirstTokenKind = Lexer.getKind();
+  switch (FirstTokenKind) {
+  default:
+    return TokError("unknown token in expression");
+  // If we have an error assume that we've already handled it.
+  case AsmToken::Error:
+    return true;
+  case AsmToken::Exclaim:
+    Lex(); // Eat the operator.
+    if (parsePrimaryExpr(Res, EndLoc))
+      return true;
+    Res = MCUnaryExpr::createLNot(Res, getContext(), FirstTokenLoc);
+    return false;
+  case AsmToken::Dollar:
+  case AsmToken::At:
+  case AsmToken::String:
+  case AsmToken::Identifier: {
+    StringRef Identifier;
+    if (parseIdentifier(Identifier)) {
+      // We may have failed but $ may be a valid token.
+      if (getTok().is(AsmToken::Dollar)) {
+        if (Lexer.getMAI().getDollarIsPC()) {
+          Lex();
+          // This is a '$' reference, which references the current PC.  Emit a
+          // temporary label to the streamer and refer to it.
+          MCSymbol *Sym = Ctx.createTempSymbol();
+          Out.emitLabel(Sym);
+          Res = MCSymbolRefExpr::create(Sym, MCSymbolRefExpr::VK_None,
+                                        getContext());
+          EndLoc = FirstTokenLoc;
+          return false;
+        }
+        return Error(FirstTokenLoc, "invalid token in expression");
+      }
+    }
+    // Parse symbol variant
+    std::pair<StringRef, StringRef> Split;
+    if (!MAI.useParensForSymbolVariant()) {
+      if (FirstTokenKind == AsmToken::String) {
+        if (Lexer.is(AsmToken::At)) {
+          Lex(); // eat @
+          SMLoc AtLoc = getLexer().getLoc();
+          StringRef VName;
+          if (parseIdentifier(VName))
+            return Error(AtLoc, "expected symbol variant after '@'");
+
+          Split = std::make_pair(Identifier, VName);
+        }
+      } else {
+        Split = Identifier.split('@');
+      }
+    } else if (Lexer.is(AsmToken::LParen)) {
+      Lex(); // eat '('.
+      StringRef VName;
+      parseIdentifier(VName);
+      // eat ')'.
+      if (parseToken(AsmToken::RParen,
+                     "unexpected token in variant, expected ')'"))
+        return true;
+      Split = std::make_pair(Identifier, VName);
+    }
+
+    EndLoc = SMLoc::getFromPointer(Identifier.end());
+
+    // This is a symbol reference.
+    StringRef SymbolName = Identifier;
+    if (SymbolName.empty())
+      return Error(getLexer().getLoc(), "expected a symbol reference");
+
+    MCSymbolRefExpr::VariantKind Variant = MCSymbolRefExpr::VK_None;
+
+    // Lookup the symbol variant if used.
+    if (!Split.second.empty()) {
+      Variant = MCSymbolRefExpr::getVariantKindForName(Split.second);
+      if (Variant != MCSymbolRefExpr::VK_Invalid) {
+        SymbolName = Split.first;
+      } else if (MAI.doesAllowAtInName() && !MAI.useParensForSymbolVariant()) {
+        Variant = MCSymbolRefExpr::VK_None;
+      } else {
+        return Error(SMLoc::getFromPointer(Split.second.begin()),
+                     "invalid variant '" + Split.second + "'");
+      }
+    }
+
+    MCSymbol *Sym = getContext().getInlineAsmLabel(SymbolName);
+    if (!Sym)
+      Sym = getContext().getOrCreateSymbol(SymbolName);
+
+    // If this is an absolute variable reference, substitute it now to preserve
+    // semantics in the face of reassignment.
+    if (Sym->isVariable()) {
+      auto V = Sym->getVariableValue(/*SetUsed*/ false);
+      bool DoInline = isa<MCConstantExpr>(V) && !Variant;
+      if (auto TV = dyn_cast<MCTargetExpr>(V))
+        DoInline = TV->inlineAssignedExpr();
+      if (DoInline) {
+        if (Variant)
+          return Error(EndLoc, "unexpected modifier on variable reference");
+        Res = Sym->getVariableValue(/*SetUsed*/ false);
+        return false;
+      }
+    }
+
+    // Otherwise create a symbol ref.
+    Res = MCSymbolRefExpr::create(Sym, Variant, getContext(), FirstTokenLoc);
+    return false;
+  }
+  case AsmToken::BigNum:
+    return TokError("literal value out of range for directive");
+  case AsmToken::Integer: {
+    SMLoc Loc = getTok().getLoc();
+    int64_t IntVal = getTok().getIntVal();
+    Res = MCConstantExpr::create(IntVal, getContext());
+    EndLoc = Lexer.getTok().getEndLoc();
+    Lex(); // Eat token.
+    // Look for 'b' or 'f' following an Integer as a directional label
+    if (Lexer.getKind() == AsmToken::Identifier) {
+      StringRef IDVal = getTok().getString();
+      // Lookup the symbol variant if used.
+      std::pair<StringRef, StringRef> Split = IDVal.split('@');
+      MCSymbolRefExpr::VariantKind Variant = MCSymbolRefExpr::VK_None;
+      if (Split.first.size() != IDVal.size()) {
+        Variant = MCSymbolRefExpr::getVariantKindForName(Split.second);
+        if (Variant == MCSymbolRefExpr::VK_Invalid)
+          return TokError("invalid variant '" + Split.second + "'");
+        IDVal = Split.first;
+      }
+      if (IDVal == "f" || IDVal == "b") {
+        MCSymbol *Sym =
+            Ctx.getDirectionalLocalSymbol(IntVal, IDVal == "b");
+        Res = MCSymbolRefExpr::create(Sym, Variant, getContext());
+        if (IDVal == "b" && Sym->isUndefined())
+          return Error(Loc, "directional label undefined");
+        DirLabels.push_back(std::make_tuple(Loc, CppHashInfo, Sym));
+        EndLoc = Lexer.getTok().getEndLoc();
+        Lex(); // Eat identifier.
+      }
+    }
+    return false;
+  }
+  case AsmToken::Real: {
+    APFloat RealVal(APFloat::IEEEdouble(), getTok().getString());
+    uint64_t IntVal = RealVal.bitcastToAPInt().getZExtValue();
+    Res = MCConstantExpr::create(IntVal, getContext());
+    EndLoc = Lexer.getTok().getEndLoc();
+    Lex(); // Eat token.
+    return false;
+  }
+  case AsmToken::Dot: {
+    // This is a '.' reference, which references the current PC.  Emit a
+    // temporary label to the streamer and refer to it.
+    MCSymbol *Sym = Ctx.createTempSymbol();
+    Out.emitLabel(Sym);
+    Res = MCSymbolRefExpr::create(Sym, MCSymbolRefExpr::VK_None, getContext());
+    EndLoc = Lexer.getTok().getEndLoc();
+    Lex(); // Eat identifier.
+    return false;
+  }
+  case AsmToken::LParen:
+    Lex(); // Eat the '('.
+    return parseParenExpr(Res, EndLoc);
+  case AsmToken::LBrac:
+    if (!PlatformParser->HasBracketExpressions())
+      return TokError("brackets expression not supported on this target");
+    Lex(); // Eat the '['.
+    return parseBracketExpr(Res, EndLoc);
+  case AsmToken::Minus:
+    Lex(); // Eat the operator.
+    if (parsePrimaryExpr(Res, EndLoc))
+      return true;
+    Res = MCUnaryExpr::createMinus(Res, getContext(), FirstTokenLoc);
+    return false;
+  case AsmToken::Plus:
+    Lex(); // Eat the operator.
+    if (parsePrimaryExpr(Res, EndLoc))
+      return true;
+    Res = MCUnaryExpr::createPlus(Res, getContext(), FirstTokenLoc);
+    return false;
+  case AsmToken::Tilde:
+    Lex(); // Eat the operator.
+    if (parsePrimaryExpr(Res, EndLoc))
+      return true;
+    Res = MCUnaryExpr::createNot(Res, getContext(), FirstTokenLoc);
+    return false;
+  // MIPS unary expression operators. The lexer won't generate these tokens if
+  // MCAsmInfo::HasMipsExpressions is false for the target.
+  case AsmToken::PercentCall16:
+  case AsmToken::PercentCall_Hi:
+  case AsmToken::PercentCall_Lo:
+  case AsmToken::PercentDtprel_Hi:
+  case AsmToken::PercentDtprel_Lo:
+  case AsmToken::PercentGot:
+  case AsmToken::PercentGot_Disp:
+  case AsmToken::PercentGot_Hi:
+  case AsmToken::PercentGot_Lo:
+  case AsmToken::PercentGot_Ofst:
+  case AsmToken::PercentGot_Page:
+  case AsmToken::PercentGottprel:
+  case AsmToken::PercentGp_Rel:
+  case AsmToken::PercentHi:
+  case AsmToken::PercentHigher:
+  case AsmToken::PercentHighest:
+  case AsmToken::PercentLo:
+  case AsmToken::PercentNeg:
+  case AsmToken::PercentPcrel_Hi:
+  case AsmToken::PercentPcrel_Lo:
+  case AsmToken::PercentTlsgd:
+  case AsmToken::PercentTlsldm:
+  case AsmToken::PercentTprel_Hi:
+  case AsmToken::PercentTprel_Lo:
+    Lex(); // Eat the operator.
+    if (Lexer.isNot(AsmToken::LParen))
+      return TokError("expected '(' after operator");
+    Lex(); // Eat the operator.
+    if (parseExpression(Res, EndLoc))
+      return true;
+    if (Lexer.isNot(AsmToken::RParen))
+      return TokError("expected ')'");
+    Lex(); // Eat the operator.
+    Res = getTargetParser().createTargetUnaryExpr(Res, FirstTokenKind, Ctx);
+    return !Res;
+  }
+}
+
+bool MasmParser::parseExpression(const MCExpr *&Res) {
+  SMLoc EndLoc;
+  return parseExpression(Res, EndLoc);
+}
+
+/// This function checks if the next token is <string> type or arithmetic.
+/// string that begin with character '<' must end with character '>'.
+/// otherwise it is arithmetics.
+/// If the function returns a 'true' value,
+/// the End argument will be filled with the last location pointed to the '>'
+/// character.
+
+/// There is a gap between the AltMacro's documentation and the single quote
+/// implementation. GCC does not fully support this feature and so we will not
+/// support it.
+/// TODO: Adding single quote as a string.
+static bool isAngleBracketString(SMLoc &StrLoc, SMLoc &EndLoc) {
+  assert((StrLoc.getPointer() != nullptr) &&
+         "Argument to the function cannot be a NULL value");
+  const char *CharPtr = StrLoc.getPointer();
+  while ((*CharPtr != '>') && (*CharPtr != '\n') && (*CharPtr != '\r') &&
+         (*CharPtr != '\0')) {
+    if (*CharPtr == '!')
+      CharPtr++;
+    CharPtr++;
+  }
+  if (*CharPtr == '>') {
+    EndLoc = StrLoc.getFromPointer(CharPtr + 1);
+    return true;
+  }
+  return false;
+}
+
+/// creating a string without the escape characters '!'.
+static std::string angleBracketString(StringRef AltMacroStr) {
+  std::string Res;
+  for (size_t Pos = 0; Pos < AltMacroStr.size(); Pos++) {
+    if (AltMacroStr[Pos] == '!')
+      Pos++;
+    Res += AltMacroStr[Pos];
+  }
+  return Res;
+}
+
+/// Parse an expression and return it.
+///
+///  expr ::= expr &&,|| expr               -> lowest.
+///  expr ::= expr |,^,&,! expr
+///  expr ::= expr ==,!=,<>,<,<=,>,>= expr
+///  expr ::= expr <<,>> expr
+///  expr ::= expr +,- expr
+///  expr ::= expr *,/,% expr               -> highest.
+///  expr ::= primaryexpr
+///
+bool MasmParser::parseExpression(const MCExpr *&Res, SMLoc &EndLoc) {
+  // Parse the expression.
+  Res = nullptr;
+  if (getTargetParser().parsePrimaryExpr(Res, EndLoc) ||
+      parseBinOpRHS(1, Res, EndLoc))
+    return true;
+
+  // Try to constant fold it up front, if possible. Do not exploit
+  // assembler here.
+  int64_t Value;
+  if (Res->evaluateAsAbsolute(Value))
+    Res = MCConstantExpr::create(Value, getContext());
+
+  return false;
+}
+
+bool MasmParser::parseParenExpression(const MCExpr *&Res, SMLoc &EndLoc) {
+  Res = nullptr;
+  return parseParenExpr(Res, EndLoc) || parseBinOpRHS(1, Res, EndLoc);
+}
+
+bool MasmParser::parseParenExprOfDepth(unsigned ParenDepth, const MCExpr *&Res,
+                                       SMLoc &EndLoc) {
+  if (parseParenExpr(Res, EndLoc))
+    return true;
+
+  for (; ParenDepth > 0; --ParenDepth) {
+    if (parseBinOpRHS(1, Res, EndLoc))
+      return true;
+
+    // We don't Lex() the last RParen.
+    // This is the same behavior as parseParenExpression().
+    if (ParenDepth - 1 > 0) {
+      EndLoc = getTok().getEndLoc();
+      if (parseToken(AsmToken::RParen,
+                     "expected ')' in parentheses expression"))
+        return true;
+    }
+  }
+  return false;
+}
+
+bool MasmParser::parseAbsoluteExpression(int64_t &Res) {
+  const MCExpr *Expr;
+
+  SMLoc StartLoc = Lexer.getLoc();
+  if (parseExpression(Expr))
+    return true;
+
+  if (!Expr->evaluateAsAbsolute(Res, getStreamer().getAssemblerPtr()))
+    return Error(StartLoc, "expected absolute expression");
+
+  return false;
+}
+
+static unsigned getGNUBinOpPrecedence(AsmToken::TokenKind K,
+                                      MCBinaryExpr::Opcode &Kind,
+                                      bool ShouldUseLogicalShr) {
+  switch (K) {
+  default:
+    return 0; // not a binop.
+
+  // Lowest Precedence: &&, ||
+  case AsmToken::AmpAmp:
+    Kind = MCBinaryExpr::LAnd;
+    return 2;
+  case AsmToken::PipePipe:
+    Kind = MCBinaryExpr::LOr;
+    return 1;
+
+  // Low Precedence: ==, !=, <>, <, <=, >, >=
+  case AsmToken::EqualEqual:
+    Kind = MCBinaryExpr::EQ;
+    return 3;
+  case AsmToken::ExclaimEqual:
+  case AsmToken::LessGreater:
+    Kind = MCBinaryExpr::NE;
+    return 3;
+  case AsmToken::Less:
+    Kind = MCBinaryExpr::LT;
+    return 3;
+  case AsmToken::LessEqual:
+    Kind = MCBinaryExpr::LTE;
+    return 3;
+  case AsmToken::Greater:
+    Kind = MCBinaryExpr::GT;
+    return 3;
+  case AsmToken::GreaterEqual:
+    Kind = MCBinaryExpr::GTE;
+    return 3;
+
+  // Low Intermediate Precedence: +, -
+  case AsmToken::Plus:
+    Kind = MCBinaryExpr::Add;
+    return 4;
+  case AsmToken::Minus:
+    Kind = MCBinaryExpr::Sub;
+    return 4;
+
+  // High Intermediate Precedence: |, &, ^
+  //
+  // FIXME: gas seems to support '!' as an infix operator?
+  case AsmToken::Pipe:
+    Kind = MCBinaryExpr::Or;
+    return 5;
+  case AsmToken::Caret:
+    Kind = MCBinaryExpr::Xor;
+    return 5;
+  case AsmToken::Amp:
+    Kind = MCBinaryExpr::And;
+    return 5;
+
+  // Highest Precedence: *, /, %, <<, >>
+  case AsmToken::Star:
+    Kind = MCBinaryExpr::Mul;
+    return 6;
+  case AsmToken::Slash:
+    Kind = MCBinaryExpr::Div;
+    return 6;
+  case AsmToken::Percent:
+    Kind = MCBinaryExpr::Mod;
+    return 6;
+  case AsmToken::LessLess:
+    Kind = MCBinaryExpr::Shl;
+    return 6;
+  case AsmToken::GreaterGreater:
+    Kind = ShouldUseLogicalShr ? MCBinaryExpr::LShr : MCBinaryExpr::AShr;
+    return 6;
+  }
+}
+
+unsigned MasmParser::getBinOpPrecedence(AsmToken::TokenKind K,
+                                        MCBinaryExpr::Opcode &Kind) {
+  bool ShouldUseLogicalShr = MAI.shouldUseLogicalShr();
+  return getGNUBinOpPrecedence(K, Kind, ShouldUseLogicalShr);
+}
+
+/// Parse all binary operators with precedence >= 'Precedence'.
+/// Res contains the LHS of the expression on input.
+bool MasmParser::parseBinOpRHS(unsigned Precedence, const MCExpr *&Res,
+                               SMLoc &EndLoc) {
+  SMLoc StartLoc = Lexer.getLoc();
+  while (true) {
+    MCBinaryExpr::Opcode Kind = MCBinaryExpr::Add;
+    unsigned TokPrec = getBinOpPrecedence(Lexer.getKind(), Kind);
+
+    // If the next token is lower precedence than we are allowed to eat, return
+    // successfully with what we ate already.
+    if (TokPrec < Precedence)
+      return false;
+
+    Lex();
+
+    // Eat the next primary expression.
+    const MCExpr *RHS;
+    if (getTargetParser().parsePrimaryExpr(RHS, EndLoc))
+      return true;
+
+    // If BinOp binds less tightly with RHS than the operator after RHS, let
+    // the pending operator take RHS as its LHS.
+    MCBinaryExpr::Opcode Dummy;
+    unsigned NextTokPrec = getBinOpPrecedence(Lexer.getKind(), Dummy);
+    if (TokPrec < NextTokPrec && parseBinOpRHS(TokPrec + 1, RHS, EndLoc))
+      return true;
+
+    // Merge LHS and RHS according to operator.
+    Res = MCBinaryExpr::create(Kind, Res, RHS, getContext(), StartLoc);
+  }
+}
+
+/// ParseStatement:
+///   ::= EndOfStatement
+///   ::= Label* Directive ...Operands... EndOfStatement
+///   ::= Label* Identifier OperandList* EndOfStatement
+bool MasmParser::parseStatement(ParseStatementInfo &Info,
+                                MCAsmParserSemaCallback *SI) {
+  assert(!hasPendingError() && "parseStatement started with pending error");
+  // Eat initial spaces and comments
+  while (Lexer.is(AsmToken::Space))
+    Lex();
+  if (Lexer.is(AsmToken::EndOfStatement)) {
+    // if this is a line comment we can drop it safely
+    if (getTok().getString().empty() || getTok().getString().front() == '\r' ||
+        getTok().getString().front() == '\n')
+      Out.AddBlankLine();
+    Lex();
+    return false;
+  }
+  // Statements always start with an identifier, unless we're dealing with a
+  // processor directive (.386, .686, etc.) that lexes as a real.
+  AsmToken ID = getTok();
+  SMLoc IDLoc = ID.getLoc();
+  StringRef IDVal;
+  int64_t LocalLabelVal = -1;
+  if (Lexer.is(AsmToken::HashDirective))
+    return parseCppHashLineFilenameComment(IDLoc);
+  // Allow an integer followed by a ':' as a directional local label.
+  if (Lexer.is(AsmToken::Integer)) {
+    LocalLabelVal = getTok().getIntVal();
+    if (LocalLabelVal < 0) {
+      if (!TheCondState.Ignore) {
+        Lex(); // always eat a token
+        return Error(IDLoc, "unexpected token at start of statement");
+      }
+      IDVal = "";
+    } else {
+      IDVal = getTok().getString();
+      Lex(); // Consume the integer token to be used as an identifier token.
+      if (Lexer.getKind() != AsmToken::Colon) {
+        if (!TheCondState.Ignore) {
+          Lex(); // always eat a token
+          return Error(IDLoc, "unexpected token at start of statement");
+        }
+      }
+    }
+  } else if (Lexer.is(AsmToken::Dot)) {
+    // Treat '.' as a valid identifier in this context.
+    Lex();
+    IDVal = ".";
+  } else if (Lexer.is(AsmToken::LCurly)) {
+    // Treat '{' as a valid identifier in this context.
+    Lex();
+    IDVal = "{";
+
+  } else if (Lexer.is(AsmToken::RCurly)) {
+    // Treat '}' as a valid identifier in this context.
+    Lex();
+    IDVal = "}";
+  } else if (Lexer.is(AsmToken::Star) &&
+             getTargetParser().starIsStartOfStatement()) {
+    // Accept '*' as a valid start of statement.
+    Lex();
+    IDVal = "*";
+  } else if (Lexer.is(AsmToken::Real)) {
+    // Treat ".<number>" as a valid identifier in this context.
+    IDVal = getTok().getString();
+    Lex(); // always eat a token
+    if (!IDVal.startswith("."))
+      return Error(IDLoc, "unexpected token at start of statement");
+  } else if (parseIdentifier(IDVal)) {
+    if (!TheCondState.Ignore) {
+      Lex(); // always eat a token
+      return Error(IDLoc, "unexpected token at start of statement");
+    }
+    IDVal = "";
+  }
+
+  // Handle conditional assembly here before checking for skipping.  We
+  // have to do this so that .endif isn't skipped in a ".if 0" block for
+  // example.
+  StringMap<DirectiveKind>::const_iterator DirKindIt =
+      DirectiveKindMap.find(IDVal.lower());
+  DirectiveKind DirKind = (DirKindIt == DirectiveKindMap.end())
+                              ? DK_NO_DIRECTIVE
+                              : DirKindIt->getValue();
+  switch (DirKind) {
+  default:
+    break;
+  case DK_IF:
+  case DK_IFE:
+    return parseDirectiveIf(IDLoc, DirKind);
+  case DK_IFB:
+    return parseDirectiveIfb(IDLoc, true);
+  case DK_IFNB:
+    return parseDirectiveIfb(IDLoc, false);
+  case DK_IFDEF:
+    return parseDirectiveIfdef(IDLoc, true);
+  case DK_IFNDEF:
+    return parseDirectiveIfdef(IDLoc, false);
+  case DK_IFDIF:
+    return parseDirectiveIfidn(IDLoc, /*ExpectEqual=*/false,
+                               /*CaseInsensitive=*/false);
+  case DK_IFDIFI:
+    return parseDirectiveIfidn(IDLoc, /*ExpectEqual=*/false,
+                               /*CaseInsensitive=*/true);
+  case DK_IFIDN:
+    return parseDirectiveIfidn(IDLoc, /*ExpectEqual=*/true,
+                               /*CaseInsensitive=*/false);
+  case DK_IFIDNI:
+    return parseDirectiveIfidn(IDLoc, /*ExpectEqual=*/true,
+                               /*CaseInsensitive=*/true);
+  case DK_ELSEIF:
+  case DK_ELSEIFE:
+    return parseDirectiveElseIf(IDLoc, DirKind);
+  case DK_ELSEIFB:
+    return parseDirectiveElseIfb(IDLoc, true);
+  case DK_ELSEIFNB:
+    return parseDirectiveElseIfb(IDLoc, false);
+  case DK_ELSEIFDEF:
+    return parseDirectiveElseIfdef(IDLoc, true);
+  case DK_ELSEIFNDEF:
+    return parseDirectiveElseIfdef(IDLoc, false);
+  case DK_ELSEIFDIF:
+    return parseDirectiveElseIfidn(IDLoc, /*ExpectEqual=*/false,
+                                   /*CaseInsensitive=*/false);
+  case DK_ELSEIFDIFI:
+    return parseDirectiveElseIfidn(IDLoc, /*ExpectEqual=*/false,
+                                   /*CaseInsensitive=*/true);
+  case DK_ELSEIFIDN:
+    return parseDirectiveElseIfidn(IDLoc, /*ExpectEqual=*/true,
+                                   /*CaseInsensitive=*/false);
+  case DK_ELSEIFIDNI:
+    return parseDirectiveElseIfidn(IDLoc, /*ExpectEqual=*/true,
+                                   /*CaseInsensitive=*/true);
+  case DK_ELSE:
+    return parseDirectiveElse(IDLoc);
+  case DK_ENDIF:
+    return parseDirectiveEndIf(IDLoc);
+  }
+
+  // Ignore the statement if in the middle of inactive conditional
+  // (e.g. ".if 0").
+  if (TheCondState.Ignore) {
+    eatToEndOfStatement();
+    return false;
+  }
+
+  // FIXME: Recurse on local labels?
+
+  // See what kind of statement we have.
+  switch (Lexer.getKind()) {
+  case AsmToken::Colon: {
+    if (!getTargetParser().isLabel(ID))
+      break;
+    if (checkForValidSection())
+      return true;
+
+    // identifier ':'   -> Label.
+    Lex();
+
+    // Diagnose attempt to use '.' as a label.
+    if (IDVal == ".")
+      return Error(IDLoc, "invalid use of pseudo-symbol '.' as a label");
+
+    // Diagnose attempt to use a variable as a label.
+    //
+    // FIXME: Diagnostics. Note the location of the definition as a label.
+    // FIXME: This doesn't diagnose assignment to a symbol which has been
+    // implicitly marked as external.
+    MCSymbol *Sym;
+    if (LocalLabelVal == -1) {
+      if (ParsingInlineAsm && SI) {
+        StringRef RewrittenLabel =
+            SI->LookupInlineAsmLabel(IDVal, getSourceManager(), IDLoc, true);
+        assert(!RewrittenLabel.empty() &&
+               "We should have an internal name here.");
+        Info.AsmRewrites->emplace_back(AOK_Label, IDLoc, IDVal.size(),
+                                       RewrittenLabel);
+        IDVal = RewrittenLabel;
+      }
+      Sym = getContext().getOrCreateSymbol(IDVal);
+    } else
+      Sym = Ctx.createDirectionalLocalSymbol(LocalLabelVal);
+    // End of Labels should be treated as end of line for lexing
+    // purposes but that information is not available to the Lexer who
+    // does not understand Labels. This may cause us to see a Hash
+    // here instead of a preprocessor line comment.
+    if (getTok().is(AsmToken::Hash)) {
+      StringRef CommentStr = parseStringToEndOfStatement();
+      Lexer.Lex();
+      Lexer.UnLex(AsmToken(AsmToken::EndOfStatement, CommentStr));
+    }
+
+    // Consume any end of statement token, if present, to avoid spurious
+    // AddBlankLine calls().
+    if (getTok().is(AsmToken::EndOfStatement)) {
+      Lex();
+    }
+
+    getTargetParser().doBeforeLabelEmit(Sym);
+
+    // Emit the label.
+    if (!getTargetParser().isParsingInlineAsm())
+      Out.emitLabel(Sym, IDLoc);
+
+    // If we are generating dwarf for assembly source files then gather the
+    // info to make a dwarf label entry for this label if needed.
+    if (enabledGenDwarfForAssembly())
+      MCGenDwarfLabelEntry::Make(Sym, &getStreamer(), getSourceManager(),
+                                 IDLoc);
+
+    getTargetParser().onLabelParsed(Sym);
+
+    return false;
+  }
+
+  default: // Normal instruction or directive.
+    break;
+  }
+
+  // If macros are enabled, check to see if this is a macro instantiation.
+  if (areMacrosEnabled())
+    if (const MCAsmMacro *M = getContext().lookupMacro(IDVal)) {
+      return handleMacroEntry(M, IDLoc);
+    }
+
+  // Otherwise, we have a normal instruction or directive.
+
+  if (DirKind != DK_NO_DIRECTIVE) {
+    // There are several entities interested in parsing directives:
+    //
+    // 1. Asm parser extensions. For example, platform-specific parsers
+    //    (like the ELF parser) register themselves as extensions.
+    // 2. The target-specific assembly parser. Some directives are target
+    //    specific or may potentially behave 
diff erently on certain targets.
+    // 3. The generic directive parser implemented by this class. These are
+    //    all the directives that behave in a target and platform independent
+    //    manner, or at least have a default behavior that's shared between
+    //    all targets and platforms.
+
+    getTargetParser().flushPendingInstructions(getStreamer());
+
+    // First, check the extension directive map to see if any extension has
+    // registered itself to parse this directive.
+    std::pair<MCAsmParserExtension *, DirectiveHandler> Handler =
+        ExtensionDirectiveMap.lookup(IDVal.lower());
+    if (Handler.first)
+      return (*Handler.second)(Handler.first, IDVal, IDLoc);
+
+    // Next, let the target-specific assembly parser try.
+    SMLoc StartTokLoc = getTok().getLoc();
+    bool TPDirectiveReturn =
+        ID.is(AsmToken::Identifier) && getTargetParser().ParseDirective(ID);
+
+    if (hasPendingError())
+      return true;
+    // Currently the return value should be true if we are
+    // uninterested but as this is at odds with the standard parsing
+    // convention (return true = error) we have instances of a parsed
+    // directive that fails returning true as an error. Catch these
+    // cases as best as possible errors here.
+    if (TPDirectiveReturn && StartTokLoc != getTok().getLoc())
+      return true;
+    // Return if we did some parsing or believe we succeeded.
+    if (!TPDirectiveReturn || StartTokLoc != getTok().getLoc())
+      return false;
+
+    // Finally, if no one else is interested in this directive, it must be
+    // generic and familiar to this class.
+    switch (DirKind) {
+    default:
+      break;
+    case DK_ASCII:
+      return parseDirectiveAscii(IDVal, false);
+    case DK_ASCIZ:
+    case DK_STRING:
+      return parseDirectiveAscii(IDVal, true);
+    case DK_BYTE:
+    case DK_SBYTE:
+    case DK_DB:
+      return parseDirectiveValue(IDVal, 1);
+    case DK_WORD:
+    case DK_SWORD:
+    case DK_DW:
+      return parseDirectiveValue(IDVal, 2);
+    case DK_DWORD:
+    case DK_SDWORD:
+    case DK_DD:
+      return parseDirectiveValue(IDVal, 4);
+    case DK_FWORD:
+      return parseDirectiveValue(IDVal, 6);
+    case DK_QWORD:
+    case DK_SQWORD:
+    case DK_DQ:
+      return parseDirectiveValue(IDVal, 8);
+    case DK_REAL4:
+      return parseDirectiveRealValue(IDVal, APFloat::IEEEsingle());
+    case DK_REAL8:
+      return parseDirectiveRealValue(IDVal, APFloat::IEEEdouble());
+    case DK_ALIGN:
+      return parseDirectiveAlign();
+    case DK_ORG:
+      return parseDirectiveOrg();
+    case DK_EXTERN:
+      eatToEndOfStatement(); // .extern is the default, ignore it.
+      return false;
+    case DK_PUBLIC:
+      return parseDirectiveSymbolAttribute(MCSA_Global);
+    case DK_COMM:
+      return parseDirectiveComm(/*IsLocal=*/false);
+    case DK_COMMENT:
+      return parseDirectiveComment(IDLoc);
+    case DK_INCLUDE:
+      return parseDirectiveInclude();
+    case DK_REPT:
+      return parseDirectiveRept(IDLoc, IDVal);
+    case DK_IRP:
+      return parseDirectiveIrp(IDLoc);
+    case DK_IRPC:
+      return parseDirectiveIrpc(IDLoc);
+    case DK_ENDR:
+      return parseDirectiveEndr(IDLoc);
+    case DK_FILE:
+      return parseDirectiveFile(IDLoc);
+    case DK_LINE:
+      return parseDirectiveLine();
+    case DK_LOC:
+      return parseDirectiveLoc();
+    case DK_STABS:
+      return parseDirectiveStabs();
+    case DK_CV_FILE:
+      return parseDirectiveCVFile();
+    case DK_CV_FUNC_ID:
+      return parseDirectiveCVFuncId();
+    case DK_CV_INLINE_SITE_ID:
+      return parseDirectiveCVInlineSiteId();
+    case DK_CV_LOC:
+      return parseDirectiveCVLoc();
+    case DK_CV_LINETABLE:
+      return parseDirectiveCVLinetable();
+    case DK_CV_INLINE_LINETABLE:
+      return parseDirectiveCVInlineLinetable();
+    case DK_CV_DEF_RANGE:
+      return parseDirectiveCVDefRange();
+    case DK_CV_STRING:
+      return parseDirectiveCVString();
+    case DK_CV_STRINGTABLE:
+      return parseDirectiveCVStringTable();
+    case DK_CV_FILECHECKSUMS:
+      return parseDirectiveCVFileChecksums();
+    case DK_CV_FILECHECKSUM_OFFSET:
+      return parseDirectiveCVFileChecksumOffset();
+    case DK_CV_FPO_DATA:
+      return parseDirectiveCVFPOData();
+    case DK_CFI_SECTIONS:
+      return parseDirectiveCFISections();
+    case DK_CFI_STARTPROC:
+      return parseDirectiveCFIStartProc();
+    case DK_CFI_ENDPROC:
+      return parseDirectiveCFIEndProc();
+    case DK_CFI_DEF_CFA:
+      return parseDirectiveCFIDefCfa(IDLoc);
+    case DK_CFI_DEF_CFA_OFFSET:
+      return parseDirectiveCFIDefCfaOffset();
+    case DK_CFI_ADJUST_CFA_OFFSET:
+      return parseDirectiveCFIAdjustCfaOffset();
+    case DK_CFI_DEF_CFA_REGISTER:
+      return parseDirectiveCFIDefCfaRegister(IDLoc);
+    case DK_CFI_OFFSET:
+      return parseDirectiveCFIOffset(IDLoc);
+    case DK_CFI_REL_OFFSET:
+      return parseDirectiveCFIRelOffset(IDLoc);
+    case DK_CFI_PERSONALITY:
+      return parseDirectiveCFIPersonalityOrLsda(true);
+    case DK_CFI_LSDA:
+      return parseDirectiveCFIPersonalityOrLsda(false);
+    case DK_CFI_REMEMBER_STATE:
+      return parseDirectiveCFIRememberState();
+    case DK_CFI_RESTORE_STATE:
+      return parseDirectiveCFIRestoreState();
+    case DK_CFI_SAME_VALUE:
+      return parseDirectiveCFISameValue(IDLoc);
+    case DK_CFI_RESTORE:
+      return parseDirectiveCFIRestore(IDLoc);
+    case DK_CFI_ESCAPE:
+      return parseDirectiveCFIEscape();
+    case DK_CFI_RETURN_COLUMN:
+      return parseDirectiveCFIReturnColumn(IDLoc);
+    case DK_CFI_SIGNAL_FRAME:
+      return parseDirectiveCFISignalFrame();
+    case DK_CFI_UNDEFINED:
+      return parseDirectiveCFIUndefined(IDLoc);
+    case DK_CFI_REGISTER:
+      return parseDirectiveCFIRegister(IDLoc);
+    case DK_CFI_WINDOW_SAVE:
+      return parseDirectiveCFIWindowSave();
+    case DK_MACRO:
+      return parseDirectiveMacro(IDLoc);
+    case DK_ALTMACRO:
+    case DK_NOALTMACRO:
+      return parseDirectiveAltmacro(IDVal);
+    case DK_EXITM:
+      return parseDirectiveExitMacro(IDVal);
+    case DK_ENDM:
+      return parseDirectiveEndMacro(IDVal);
+    case DK_PURGEM:
+      return parseDirectivePurgeMacro(IDLoc);
+    case DK_END:
+      return parseDirectiveEnd(IDLoc);
+    case DK_ERR:
+      return parseDirectiveError(IDLoc);
+    case DK_ERRB:
+      return parseDirectiveErrorIfb(IDLoc, true);
+    case DK_ERRNB:
+      return parseDirectiveErrorIfb(IDLoc, false);
+    case DK_ERRDEF:
+      return parseDirectiveErrorIfdef(IDLoc, true);
+    case DK_ERRNDEF:
+      return parseDirectiveErrorIfdef(IDLoc, false);
+    case DK_ERRDIF:
+      return parseDirectiveErrorIfidn(IDLoc, /*ExpectEqual=*/false,
+                                      /*CaseInsensitive=*/false);
+    case DK_ERRDIFI:
+      return parseDirectiveErrorIfidn(IDLoc, /*ExpectEqual=*/false,
+                                      /*CaseInsensitive=*/true);
+    case DK_ERRIDN:
+      return parseDirectiveErrorIfidn(IDLoc, /*ExpectEqual=*/true,
+                                      /*CaseInsensitive=*/false);
+    case DK_ERRIDNI:
+      return parseDirectiveErrorIfidn(IDLoc, /*ExpectEqual=*/true,
+                                      /*CaseInsensitive=*/true);
+    case DK_ERRE:
+      return parseDirectiveErrorIfe(IDLoc, true);
+    case DK_ERRNZ:
+      return parseDirectiveErrorIfe(IDLoc, false);
+    case DK_ECHO:
+      return parseDirectiveEcho();
+    }
+
+    return Error(IDLoc, "unknown directive");
+  }
+
+  // Non-conditional Microsoft directives sometimes follow their first argument.
+  const AsmToken nextTok = getTok();
+  const StringRef nextVal = nextTok.getString();
+  const SMLoc nextLoc = nextTok.getLoc();
+
+  // There are several entities interested in parsing infix directives:
+  //
+  // 1. Asm parser extensions. For example, platform-specific parsers
+  //    (like the ELF parser) register themselves as extensions.
+  // 2. The generic directive parser implemented by this class. These are
+  //    all the directives that behave in a target and platform independent
+  //    manner, or at least have a default behavior that's shared between
+  //    all targets and platforms.
+
+  getTargetParser().flushPendingInstructions(getStreamer());
+
+  // First, check the extension directive map to see if any extension has
+  // registered itself to parse this directive.
+  std::pair<MCAsmParserExtension *, DirectiveHandler> Handler =
+      ExtensionDirectiveMap.lookup(nextVal.lower());
+  if (Handler.first) {
+    Lex();
+    Lexer.UnLex(ID);
+    return (*Handler.second)(Handler.first, nextVal, nextLoc);
+  }
+
+  // Finally, if no one else is interested in this directive, it must be
+  // generic and familiar to this class.
+  DirKindIt = DirectiveKindMap.find(nextVal.lower());
+  DirKind = (DirKindIt == DirectiveKindMap.end())
+                ? DK_NO_DIRECTIVE
+                : DirKindIt->getValue();
+  switch (DirKind) {
+  default:
+    break;
+  case DK_ASSIGN:
+  case DK_EQU:
+  case DK_TEXTEQU:
+    Lex();
+    return parseDirectiveEquate(nextVal, IDVal, DirKind);
+  }
+
+  // __asm _emit or __asm __emit
+  if (ParsingInlineAsm && (IDVal == "_emit" || IDVal == "__emit" ||
+                           IDVal == "_EMIT" || IDVal == "__EMIT"))
+    return parseDirectiveMSEmit(IDLoc, Info, IDVal.size());
+
+  // __asm align
+  if (ParsingInlineAsm && (IDVal == "align" || IDVal == "ALIGN"))
+    return parseDirectiveMSAlign(IDLoc, Info);
+
+  if (ParsingInlineAsm && (IDVal == "even" || IDVal == "EVEN"))
+    Info.AsmRewrites->emplace_back(AOK_EVEN, IDLoc, 4);
+  if (checkForValidSection())
+    return true;
+
+  // Canonicalize the opcode to lower case.
+  std::string OpcodeStr = IDVal.lower();
+  ParseInstructionInfo IInfo(Info.AsmRewrites);
+  bool ParseHadError = getTargetParser().ParseInstruction(IInfo, OpcodeStr, ID,
+                                                          Info.ParsedOperands);
+  Info.ParseError = ParseHadError;
+
+  // Dump the parsed representation, if requested.
+  if (getShowParsedOperands()) {
+    SmallString<256> Str;
+    raw_svector_ostream OS(Str);
+    OS << "parsed instruction: [";
+    for (unsigned i = 0; i != Info.ParsedOperands.size(); ++i) {
+      if (i != 0)
+        OS << ", ";
+      Info.ParsedOperands[i]->print(OS);
+    }
+    OS << "]";
+
+    printMessage(IDLoc, SourceMgr::DK_Note, OS.str());
+  }
+
+  // Fail even if ParseInstruction erroneously returns false.
+  if (hasPendingError() || ParseHadError)
+    return true;
+
+  // If we are generating dwarf for the current section then generate a .loc
+  // directive for the instruction.
+  if (!ParseHadError && enabledGenDwarfForAssembly() &&
+      getContext().getGenDwarfSectionSyms().count(
+          getStreamer().getCurrentSectionOnly())) {
+    unsigned Line;
+    if (ActiveMacros.empty())
+      Line = SrcMgr.FindLineNumber(IDLoc, CurBuffer);
+    else
+      Line = SrcMgr.FindLineNumber(ActiveMacros.front()->InstantiationLoc,
+                                   ActiveMacros.front()->ExitBuffer);
+
+    // If we previously parsed a cpp hash file line comment then make sure the
+    // current Dwarf File is for the CppHashFilename if not then emit the
+    // Dwarf File table for it and adjust the line number for the .loc.
+    if (!CppHashInfo.Filename.empty()) {
+      unsigned FileNumber = getStreamer().emitDwarfFileDirective(
+          0, StringRef(), CppHashInfo.Filename);
+      getContext().setGenDwarfFileNumber(FileNumber);
+
+      unsigned CppHashLocLineNo =
+        SrcMgr.FindLineNumber(CppHashInfo.Loc, CppHashInfo.Buf);
+      Line = CppHashInfo.LineNumber - 1 + (Line - CppHashLocLineNo);
+    }
+
+    getStreamer().emitDwarfLocDirective(
+        getContext().getGenDwarfFileNumber(), Line, 0,
+        DWARF2_LINE_DEFAULT_IS_STMT ? DWARF2_FLAG_IS_STMT : 0, 0, 0,
+        StringRef());
+  }
+
+  // If parsing succeeded, match the instruction.
+  if (!ParseHadError) {
+    uint64_t ErrorInfo;
+    if (getTargetParser().MatchAndEmitInstruction(
+            IDLoc, Info.Opcode, Info.ParsedOperands, Out, ErrorInfo,
+            getTargetParser().isParsingInlineAsm()))
+      return true;
+  }
+  return false;
+}
+
+// Parse and erase curly braces marking block start/end
+bool MasmParser::parseCurlyBlockScope(
+    SmallVectorImpl<AsmRewrite> &AsmStrRewrites) {
+  // Identify curly brace marking block start/end
+  if (Lexer.isNot(AsmToken::LCurly) && Lexer.isNot(AsmToken::RCurly))
+    return false;
+
+  SMLoc StartLoc = Lexer.getLoc();
+  Lex(); // Eat the brace
+  if (Lexer.is(AsmToken::EndOfStatement))
+    Lex(); // Eat EndOfStatement following the brace
+
+  // Erase the block start/end brace from the output asm string
+  AsmStrRewrites.emplace_back(AOK_Skip, StartLoc, Lexer.getLoc().getPointer() -
+                                                  StartLoc.getPointer());
+  return true;
+}
+
+/// parseCppHashLineFilenameComment as this:
+///   ::= # number "filename"
+bool MasmParser::parseCppHashLineFilenameComment(SMLoc L) {
+  Lex(); // Eat the hash token.
+  // Lexer only ever emits HashDirective if it fully formed if it's
+  // done the checking already so this is an internal error.
+  assert(getTok().is(AsmToken::Integer) &&
+         "Lexing Cpp line comment: Expected Integer");
+  int64_t LineNumber = getTok().getIntVal();
+  Lex();
+  assert(getTok().is(AsmToken::String) &&
+         "Lexing Cpp line comment: Expected String");
+  StringRef Filename = getTok().getString();
+  Lex();
+
+  // Get rid of the enclosing quotes.
+  Filename = Filename.substr(1, Filename.size() - 2);
+
+  // Save the SMLoc, Filename and LineNumber for later use by diagnostics
+  // and possibly DWARF file info.
+  CppHashInfo.Loc = L;
+  CppHashInfo.Filename = Filename;
+  CppHashInfo.LineNumber = LineNumber;
+  CppHashInfo.Buf = CurBuffer;
+  if (FirstCppHashFilename.empty())
+    FirstCppHashFilename = Filename;
+  return false;
+}
+
+/// will use the last parsed cpp hash line filename comment
+/// for the Filename and LineNo if any in the diagnostic.
+void MasmParser::DiagHandler(const SMDiagnostic &Diag, void *Context) {
+  const MasmParser *Parser = static_cast<const MasmParser *>(Context);
+  raw_ostream &OS = errs();
+
+  const SourceMgr &DiagSrcMgr = *Diag.getSourceMgr();
+  SMLoc DiagLoc = Diag.getLoc();
+  unsigned DiagBuf = DiagSrcMgr.FindBufferContainingLoc(DiagLoc);
+  unsigned CppHashBuf =
+      Parser->SrcMgr.FindBufferContainingLoc(Parser->CppHashInfo.Loc);
+
+  // Like SourceMgr::printMessage() we need to print the include stack if any
+  // before printing the message.
+  unsigned DiagCurBuffer = DiagSrcMgr.FindBufferContainingLoc(DiagLoc);
+  if (!Parser->SavedDiagHandler && DiagCurBuffer &&
+      DiagCurBuffer != DiagSrcMgr.getMainFileID()) {
+    SMLoc ParentIncludeLoc = DiagSrcMgr.getParentIncludeLoc(DiagCurBuffer);
+    DiagSrcMgr.PrintIncludeStack(ParentIncludeLoc, OS);
+  }
+
+  // If we have not parsed a cpp hash line filename comment or the source
+  // manager changed or buffer changed (like in a nested include) then just
+  // print the normal diagnostic using its Filename and LineNo.
+  if (!Parser->CppHashInfo.LineNumber || &DiagSrcMgr != &Parser->SrcMgr ||
+      DiagBuf != CppHashBuf) {
+    if (Parser->SavedDiagHandler)
+      Parser->SavedDiagHandler(Diag, Parser->SavedDiagContext);
+    else
+      Diag.print(nullptr, OS);
+    return;
+  }
+
+  // Use the CppHashFilename and calculate a line number based on the
+  // CppHashInfo.Loc and CppHashInfo.LineNumber relative to this Diag's SMLoc
+  // for the diagnostic.
+  const std::string &Filename = std::string(Parser->CppHashInfo.Filename);
+
+  int DiagLocLineNo = DiagSrcMgr.FindLineNumber(DiagLoc, DiagBuf);
+  int CppHashLocLineNo =
+      Parser->SrcMgr.FindLineNumber(Parser->CppHashInfo.Loc, CppHashBuf);
+  int LineNo =
+      Parser->CppHashInfo.LineNumber - 1 + (DiagLocLineNo - CppHashLocLineNo);
+
+  SMDiagnostic NewDiag(*Diag.getSourceMgr(), Diag.getLoc(), Filename, LineNo,
+                       Diag.getColumnNo(), Diag.getKind(), Diag.getMessage(),
+                       Diag.getLineContents(), Diag.getRanges());
+
+  if (Parser->SavedDiagHandler)
+    Parser->SavedDiagHandler(NewDiag, Parser->SavedDiagContext);
+  else
+    NewDiag.print(nullptr, OS);
+}
+
+// FIXME: This is mostly duplicated from the function in AsmLexer.cpp. The
+// 
diff erence being that that function accepts '@' as part of identifiers and
+// we can't do that. AsmLexer.cpp should probably be changed to handle
+// '@' as a special case when needed.
+static bool isIdentifierChar(char c) {
+  return isalnum(static_cast<unsigned char>(c)) || c == '_' || c == '$' ||
+         c == '.';
+}
+
+bool MasmParser::expandMacro(raw_svector_ostream &OS, StringRef Body,
+                             ArrayRef<MCAsmMacroParameter> Parameters,
+                             ArrayRef<MCAsmMacroArgument> A,
+                             bool EnableAtPseudoVariable, SMLoc L) {
+  unsigned NParameters = Parameters.size();
+  bool HasVararg = NParameters ? Parameters.back().Vararg : false;
+  if ((!IsDarwin || NParameters != 0) && NParameters != A.size())
+    return Error(L, "Wrong number of arguments");
+
+  // A macro without parameters is handled 
diff erently on Darwin:
+  // gas accepts no arguments and does no substitutions
+  while (!Body.empty()) {
+    // Scan for the next substitution.
+    std::size_t End = Body.size(), Pos = 0;
+    for (; Pos != End; ++Pos) {
+      // Check for a substitution or escape.
+      if (IsDarwin && !NParameters) {
+        // This macro has no parameters, look for $0, $1, etc.
+        if (Body[Pos] != '$' || Pos + 1 == End)
+          continue;
+
+        char Next = Body[Pos + 1];
+        if (Next == '$' || Next == 'n' ||
+            isdigit(static_cast<unsigned char>(Next)))
+          break;
+      } else {
+        // This macro has parameters, look for \foo, \bar, etc.
+        if (Body[Pos] == '\\' && Pos + 1 != End)
+          break;
+      }
+    }
+
+    // Add the prefix.
+    OS << Body.slice(0, Pos);
+
+    // Check if we reached the end.
+    if (Pos == End)
+      break;
+
+    if (IsDarwin && !NParameters) {
+      switch (Body[Pos + 1]) {
+      // $$ => $
+      case '$':
+        OS << '$';
+        break;
+
+      // $n => number of arguments
+      case 'n':
+        OS << A.size();
+        break;
+
+      // $[0-9] => argument
+      default: {
+        // Missing arguments are ignored.
+        unsigned Index = Body[Pos + 1] - '0';
+        if (Index >= A.size())
+          break;
+
+        // Otherwise substitute with the token values, with spaces eliminated.
+        for (const AsmToken &Token : A[Index])
+          OS << Token.getString();
+        break;
+      }
+      }
+      Pos += 2;
+    } else {
+      unsigned I = Pos + 1;
+
+      // Check for the \@ pseudo-variable.
+      if (EnableAtPseudoVariable && Body[I] == '@' && I + 1 != End)
+        ++I;
+      else
+        while (isIdentifierChar(Body[I]) && I + 1 != End)
+          ++I;
+
+      const char *Begin = Body.data() + Pos + 1;
+      StringRef Argument(Begin, I - (Pos + 1));
+      unsigned Index = 0;
+
+      if (Argument == "@") {
+        OS << NumOfMacroInstantiations;
+        Pos += 2;
+      } else {
+        for (; Index < NParameters; ++Index)
+          if (Parameters[Index].Name == Argument)
+            break;
+
+        if (Index == NParameters) {
+          if (Body[Pos + 1] == '(' && Body[Pos + 2] == ')')
+            Pos += 3;
+          else {
+            OS << '\\' << Argument;
+            Pos = I;
+          }
+        } else {
+          bool VarargParameter = HasVararg && Index == (NParameters - 1);
+          for (const AsmToken &Token : A[Index])
+            // For altmacro mode, you can write '%expr'.
+            // The prefix '%' evaluates the expression 'expr'
+            // and uses the result as a string (e.g. replace %(1+2) with the
+            // string "3").
+            // Here, we identify the integer token which is the result of the
+            // absolute expression evaluation and replace it with its string
+            // representation.
+            if (AltMacroMode && Token.getString().front() == '%' &&
+                Token.is(AsmToken::Integer))
+              // Emit an integer value to the buffer.
+              OS << Token.getIntVal();
+            // Only Token that was validated as a string and begins with '<'
+            // is considered altMacroString!!!
+            else if (AltMacroMode && Token.getString().front() == '<' &&
+                     Token.is(AsmToken::String)) {
+              OS << angleBracketString(Token.getStringContents());
+            }
+            // We expect no quotes around the string's contents when
+            // parsing for varargs.
+            else if (Token.isNot(AsmToken::String) || VarargParameter)
+              OS << Token.getString();
+            else
+              OS << Token.getStringContents();
+
+          Pos += 1 + Argument.size();
+        }
+      }
+    }
+    // Update the scan point.
+    Body = Body.substr(Pos);
+  }
+
+  return false;
+}
+
+static bool isOperator(AsmToken::TokenKind kind) {
+  switch (kind) {
+  default:
+    return false;
+  case AsmToken::Plus:
+  case AsmToken::Minus:
+  case AsmToken::Tilde:
+  case AsmToken::Slash:
+  case AsmToken::Star:
+  case AsmToken::Dot:
+  case AsmToken::Equal:
+  case AsmToken::EqualEqual:
+  case AsmToken::Pipe:
+  case AsmToken::PipePipe:
+  case AsmToken::Caret:
+  case AsmToken::Amp:
+  case AsmToken::AmpAmp:
+  case AsmToken::Exclaim:
+  case AsmToken::ExclaimEqual:
+  case AsmToken::Less:
+  case AsmToken::LessEqual:
+  case AsmToken::LessLess:
+  case AsmToken::LessGreater:
+  case AsmToken::Greater:
+  case AsmToken::GreaterEqual:
+  case AsmToken::GreaterGreater:
+    return true;
+  }
+}
+
+namespace {
+
+class AsmLexerSkipSpaceRAII {
+public:
+  AsmLexerSkipSpaceRAII(AsmLexer &Lexer, bool SkipSpace) : Lexer(Lexer) {
+    Lexer.setSkipSpace(SkipSpace);
+  }
+
+  ~AsmLexerSkipSpaceRAII() {
+    Lexer.setSkipSpace(true);
+  }
+
+private:
+  AsmLexer &Lexer;
+};
+
+} // end anonymous namespace
+
+bool MasmParser::parseMacroArgument(MCAsmMacroArgument &MA, bool Vararg) {
+
+  if (Vararg) {
+    if (Lexer.isNot(AsmToken::EndOfStatement)) {
+      StringRef Str = parseStringToEndOfStatement();
+      MA.emplace_back(AsmToken::String, Str);
+    }
+    return false;
+  }
+
+  unsigned ParenLevel = 0;
+
+  // Darwin doesn't use spaces to delmit arguments.
+  AsmLexerSkipSpaceRAII ScopedSkipSpace(Lexer, IsDarwin);
+
+  bool SpaceEaten;
+
+  while (true) {
+    SpaceEaten = false;
+    if (Lexer.is(AsmToken::Eof) || Lexer.is(AsmToken::Equal))
+      return TokError("unexpected token in macro instantiation");
+
+    if (ParenLevel == 0) {
+
+      if (Lexer.is(AsmToken::Comma))
+        break;
+
+      if (Lexer.is(AsmToken::Space)) {
+        SpaceEaten = true;
+        Lexer.Lex(); // Eat spaces
+      }
+
+      // Spaces can delimit parameters, but could also be part an expression.
+      // If the token after a space is an operator, add the token and the next
+      // one into this argument
+      if (!IsDarwin) {
+        if (isOperator(Lexer.getKind())) {
+          MA.push_back(getTok());
+          Lexer.Lex();
+
+          // Whitespace after an operator can be ignored.
+          if (Lexer.is(AsmToken::Space))
+            Lexer.Lex();
+
+          continue;
+        }
+      }
+      if (SpaceEaten)
+        break;
+    }
+
+    // handleMacroEntry relies on not advancing the lexer here
+    // to be able to fill in the remaining default parameter values
+    if (Lexer.is(AsmToken::EndOfStatement))
+      break;
+
+    // Adjust the current parentheses level.
+    if (Lexer.is(AsmToken::LParen))
+      ++ParenLevel;
+    else if (Lexer.is(AsmToken::RParen) && ParenLevel)
+      --ParenLevel;
+
+    // Append the token to the current argument list.
+    MA.push_back(getTok());
+    Lexer.Lex();
+  }
+
+  if (ParenLevel != 0)
+    return TokError("unbalanced parentheses in macro argument");
+  return false;
+}
+
+// Parse the macro instantiation arguments.
+bool MasmParser::parseMacroArguments(const MCAsmMacro *M,
+                                     MCAsmMacroArguments &A) {
+  const unsigned NParameters = M ? M->Parameters.size() : 0;
+  bool NamedParametersFound = false;
+  SmallVector<SMLoc, 4> FALocs;
+
+  A.resize(NParameters);
+  FALocs.resize(NParameters);
+
+  // Parse two kinds of macro invocations:
+  // - macros defined without any parameters accept an arbitrary number of them
+  // - macros defined with parameters accept at most that many of them
+  bool HasVararg = NParameters ? M->Parameters.back().Vararg : false;
+  for (unsigned Parameter = 0; !NParameters || Parameter < NParameters;
+       ++Parameter) {
+    SMLoc IDLoc = Lexer.getLoc();
+    MCAsmMacroParameter FA;
+
+    if (Lexer.is(AsmToken::Identifier) && Lexer.peekTok().is(AsmToken::Equal)) {
+      if (parseIdentifier(FA.Name))
+        return Error(IDLoc, "invalid argument identifier for formal argument");
+
+      if (Lexer.isNot(AsmToken::Equal))
+        return TokError("expected '=' after formal parameter identifier");
+
+      Lex();
+
+      NamedParametersFound = true;
+    }
+    bool Vararg = HasVararg && Parameter == (NParameters - 1);
+
+    if (NamedParametersFound && FA.Name.empty())
+      return Error(IDLoc, "cannot mix positional and keyword arguments");
+
+    SMLoc StrLoc = Lexer.getLoc();
+    SMLoc EndLoc;
+    if (AltMacroMode && Lexer.is(AsmToken::Percent)) {
+      const MCExpr *AbsoluteExp;
+      int64_t Value;
+      /// Eat '%'
+      Lex();
+      if (parseExpression(AbsoluteExp, EndLoc))
+        return false;
+      if (!AbsoluteExp->evaluateAsAbsolute(Value,
+                                           getStreamer().getAssemblerPtr()))
+        return Error(StrLoc, "expected absolute expression");
+      const char *StrChar = StrLoc.getPointer();
+      const char *EndChar = EndLoc.getPointer();
+      AsmToken newToken(AsmToken::Integer,
+                        StringRef(StrChar, EndChar - StrChar), Value);
+      FA.Value.push_back(newToken);
+    } else if (AltMacroMode && Lexer.is(AsmToken::Less) &&
+               isAngleBracketString(StrLoc, EndLoc)) {
+      const char *StrChar = StrLoc.getPointer();
+      const char *EndChar = EndLoc.getPointer();
+      jumpToLoc(EndLoc, CurBuffer);
+      /// Eat from '<' to '>'
+      Lex();
+      AsmToken newToken(AsmToken::String,
+                        StringRef(StrChar, EndChar - StrChar));
+      FA.Value.push_back(newToken);
+    } else if(parseMacroArgument(FA.Value, Vararg))
+      return true;
+
+    unsigned PI = Parameter;
+    if (!FA.Name.empty()) {
+      unsigned FAI = 0;
+      for (FAI = 0; FAI < NParameters; ++FAI)
+        if (M->Parameters[FAI].Name == FA.Name)
+          break;
+
+      if (FAI >= NParameters) {
+        assert(M && "expected macro to be defined");
+        return Error(IDLoc, "parameter named '" + FA.Name +
+                                "' does not exist for macro '" + M->Name + "'");
+      }
+      PI = FAI;
+    }
+
+    if (!FA.Value.empty()) {
+      if (A.size() <= PI)
+        A.resize(PI + 1);
+      A[PI] = FA.Value;
+
+      if (FALocs.size() <= PI)
+        FALocs.resize(PI + 1);
+
+      FALocs[PI] = Lexer.getLoc();
+    }
+
+    // At the end of the statement, fill in remaining arguments that have
+    // default values. If there aren't any, then the next argument is
+    // required but missing
+    if (Lexer.is(AsmToken::EndOfStatement)) {
+      bool Failure = false;
+      for (unsigned FAI = 0; FAI < NParameters; ++FAI) {
+        if (A[FAI].empty()) {
+          if (M->Parameters[FAI].Required) {
+            Error(FALocs[FAI].isValid() ? FALocs[FAI] : Lexer.getLoc(),
+                  "missing value for required parameter "
+                  "'" + M->Parameters[FAI].Name + "' in macro '" + M->Name + "'");
+            Failure = true;
+          }
+
+          if (!M->Parameters[FAI].Value.empty())
+            A[FAI] = M->Parameters[FAI].Value;
+        }
+      }
+      return Failure;
+    }
+
+    if (Lexer.is(AsmToken::Comma))
+      Lex();
+  }
+
+  return TokError("too many positional arguments");
+}
+
+bool MasmParser::handleMacroEntry(const MCAsmMacro *M, SMLoc NameLoc) {
+  // Arbitrarily limit macro nesting depth (default matches 'as'). We can
+  // eliminate this, although we should protect against infinite loops.
+  unsigned MaxNestingDepth = AsmMacroMaxNestingDepth;
+  if (ActiveMacros.size() == MaxNestingDepth) {
+    std::ostringstream MaxNestingDepthError;
+    MaxNestingDepthError << "macros cannot be nested more than "
+                         << MaxNestingDepth << " levels deep."
+                         << " Use -asm-macro-max-nesting-depth to increase "
+                            "this limit.";
+    return TokError(MaxNestingDepthError.str());
+  }
+
+  MCAsmMacroArguments A;
+  if (parseMacroArguments(M, A))
+    return true;
+
+  // Macro instantiation is lexical, unfortunately. We construct a new buffer
+  // to hold the macro body with substitutions.
+  SmallString<256> Buf;
+  StringRef Body = M->Body;
+  raw_svector_ostream OS(Buf);
+
+  if (expandMacro(OS, Body, M->Parameters, A, true, getTok().getLoc()))
+    return true;
+
+  // We include the .endmacro in the buffer as our cue to exit the macro
+  // instantiation.
+  OS << ".endmacro\n";
+
+  std::unique_ptr<MemoryBuffer> Instantiation =
+      MemoryBuffer::getMemBufferCopy(OS.str(), "<instantiation>");
+
+  // Create the macro instantiation object and add to the current macro
+  // instantiation stack.
+  MacroInstantiation *MI = new MacroInstantiation{
+      NameLoc, CurBuffer, getTok().getLoc(), TheCondStack.size()};
+  ActiveMacros.push_back(MI);
+
+  ++NumOfMacroInstantiations;
+
+  // Jump to the macro instantiation and prime the lexer.
+  CurBuffer = SrcMgr.AddNewSourceBuffer(std::move(Instantiation), SMLoc());
+  Lexer.setBuffer(SrcMgr.getMemoryBuffer(CurBuffer)->getBuffer());
+  Lex();
+
+  return false;
+}
+
+void MasmParser::handleMacroExit() {
+  // Jump to the EndOfStatement we should return to, and consume it.
+  jumpToLoc(ActiveMacros.back()->ExitLoc, ActiveMacros.back()->ExitBuffer);
+  Lex();
+
+  // Pop the instantiation entry.
+  delete ActiveMacros.back();
+  ActiveMacros.pop_back();
+}
+
+/// parseIdentifier:
+///   ::= identifier
+///   ::= string
+bool MasmParser::parseIdentifier(StringRef &Res) {
+  // The assembler has relaxed rules for accepting identifiers, in particular we
+  // allow things like '.globl $foo' and '.def @feat.00', which would normally
+  // be separate tokens. At this level, we have already lexed so we cannot
+  // (currently) handle this as a context dependent token, instead we detect
+  // adjacent tokens and return the combined identifier.
+  if (Lexer.is(AsmToken::Dollar) || Lexer.is(AsmToken::At)) {
+    SMLoc PrefixLoc = getLexer().getLoc();
+
+    // Consume the prefix character, and check for a following identifier.
+
+    AsmToken Buf[1];
+    Lexer.peekTokens(Buf, false);
+
+    if (Buf[0].isNot(AsmToken::Identifier))
+      return true;
+
+    // We have a '$' or '@' followed by an identifier, make sure they are adjacent.
+    if (PrefixLoc.getPointer() + 1 != Buf[0].getLoc().getPointer())
+      return true;
+
+    // eat $ or @
+    Lexer.Lex(); // Lexer's Lex guarantees consecutive token.
+    // Construct the joined identifier and consume the token.
+    Res =
+        StringRef(PrefixLoc.getPointer(), getTok().getIdentifier().size() + 1);
+    Lex(); // Parser Lex to maintain invariants.
+    return false;
+  }
+
+  if (Lexer.isNot(AsmToken::Identifier) && Lexer.isNot(AsmToken::String))
+    return true;
+
+  Res = getTok().getIdentifier();
+
+  Lex(); // Consume the identifier token.
+
+  return false;
+}
+
+/// parseDirectiveEquate:
+///  ::= name "=" expression
+///    | name "equ" expression    (not redefinable)
+///    | name "equ" text-list
+///    | name "textequ" text-list
+bool MasmParser::parseDirectiveEquate(StringRef IDVal, StringRef Name,
+                                      DirectiveKind DirKind) {
+  Variable &Var = Variables[Name];
+  if (Var.Name.empty()) {
+    Var.Name = Name;
+  } else if (!Var.Redefinable) {
+    return TokError("invalid variable redefinition");
+  }
+  Var.Redefinable = (DirKind != DK_EQU);
+
+  if (DirKind == DK_EQU || DirKind == DK_TEXTEQU) {
+    // "equ" and "textequ" both allow text expressions.
+    std::string Value;
+    if (!parseTextItem(Value)) {
+      Var.IsText = true;
+      Var.TextValue = Value;
+
+      // Accept a text-list, not just one text-item
+      auto parseItem = [&]() -> bool {
+        if (parseTextItem(Value))
+          return true;
+        Var.TextValue += Value;
+        return false;
+      };
+      if (parseOptionalToken(AsmToken::Comma) && parseMany(parseItem))
+        return addErrorSuffix(" in '" + Twine(IDVal) + "' directive");
+
+      return false;
+    }
+  }
+  if (DirKind == DK_TEXTEQU)
+    return TokError("expected <text> in '" + Twine(IDVal) + "' directive");
+
+  // Parse as expression assignment
+  const MCExpr *Expr;
+  SMLoc EndLoc, StartLoc = Lexer.getLoc();
+  if (parseExpression(Expr, EndLoc))
+    return addErrorSuffix(" in '" + Twine(IDVal) + "' directive");
+  if (Expr->evaluateAsAbsolute(Var.NumericValue,
+                               getStreamer().getAssemblerPtr()))
+    return false;
+
+  // Not an absolute expression; define as a text replacement.
+  Var.IsText = true;
+  Var.TextValue = StringRef(StartLoc.getPointer(),
+                            EndLoc.getPointer() - StartLoc.getPointer()).str();
+  return false;
+}
+
+bool MasmParser::parseEscapedString(std::string &Data) {
+  if (check(getTok().isNot(AsmToken::String), "expected string"))
+    return true;
+
+  Data = "";
+  StringRef Str = getTok().getStringContents();
+  for (unsigned i = 0, e = Str.size(); i != e; ++i) {
+    if (Str[i] != '\\') {
+      Data += Str[i];
+      continue;
+    }
+
+    // Recognize escaped characters. Note that this escape semantics currently
+    // loosely follows Darwin 'as'.
+    ++i;
+    if (i == e)
+      return TokError("unexpected backslash at end of string");
+
+    // Recognize hex sequences similarly to GNU 'as'.
+    if (Str[i] == 'x' || Str[i] == 'X') {
+      size_t length = Str.size();
+      if (i + 1 >= length || !isHexDigit(Str[i + 1]))
+        return TokError("invalid hexadecimal escape sequence");
+
+      // Consume hex characters. GNU 'as' reads all hexadecimal characters and
+      // then truncates to the lower 16 bits. Seems reasonable.
+      unsigned Value = 0;
+      while (i + 1 < length && isHexDigit(Str[i + 1]))
+        Value = Value * 16 + hexDigitValue(Str[++i]);
+
+      Data += (unsigned char)(Value & 0xFF);
+      continue;
+    }
+
+    // Recognize octal sequences.
+    if ((unsigned)(Str[i] - '0') <= 7) {
+      // Consume up to three octal characters.
+      unsigned Value = Str[i] - '0';
+
+      if (i + 1 != e && ((unsigned)(Str[i + 1] - '0')) <= 7) {
+        ++i;
+        Value = Value * 8 + (Str[i] - '0');
+
+        if (i + 1 != e && ((unsigned)(Str[i + 1] - '0')) <= 7) {
+          ++i;
+          Value = Value * 8 + (Str[i] - '0');
+        }
+      }
+
+      if (Value > 255)
+        return TokError("invalid octal escape sequence (out of range)");
+
+      Data += (unsigned char)Value;
+      continue;
+    }
+
+    // Otherwise recognize individual escapes.
+    switch (Str[i]) {
+    default:
+      // Just reject invalid escape sequences for now.
+      return TokError("invalid escape sequence (unrecognized character)");
+
+    case 'b': Data += '\b'; break;
+    case 'f': Data += '\f'; break;
+    case 'n': Data += '\n'; break;
+    case 'r': Data += '\r'; break;
+    case 't': Data += '\t'; break;
+    case '"': Data += '"'; break;
+    case '\\': Data += '\\'; break;
+    }
+  }
+
+  Lex();
+  return false;
+}
+
+bool MasmParser::parseAngleBracketString(std::string &Data) {
+  SMLoc EndLoc, StartLoc = getTok().getLoc();
+  if (isAngleBracketString(StartLoc, EndLoc)) {
+    const char *StartChar = StartLoc.getPointer() + 1;
+    const char *EndChar = EndLoc.getPointer() - 1;
+    jumpToLoc(EndLoc, CurBuffer);
+    /// Eat from '<' to '>'
+    Lex();
+
+    Data = angleBracketString(StringRef(StartChar, EndChar - StartChar));
+    return false;
+  }
+  return true;
+}
+
+/// textItem ::= textLiteral | textMacroID | % constExpr
+bool MasmParser::parseTextItem(std::string &Data) {
+  // TODO(epastor): Support textMacroID and % expansion of expressions.
+  return parseAngleBracketString(Data);
+}
+
+/// parseDirectiveAscii:
+///   ::= ( .ascii | .asciz | .string ) [ "string" ( , "string" )* ]
+bool MasmParser::parseDirectiveAscii(StringRef IDVal, bool ZeroTerminated) {
+  auto parseOp = [&]() -> bool {
+    std::string Data;
+    if (checkForValidSection() || parseEscapedString(Data))
+      return true;
+    getStreamer().emitBytes(Data);
+    if (ZeroTerminated)
+      getStreamer().emitBytes(StringRef("\0", 1));
+    return false;
+  };
+
+  if (parseMany(parseOp))
+    return addErrorSuffix(" in '" + Twine(IDVal) + "' directive");
+  return false;
+}
+
+/// parseDirectiveValue
+///  ::= (byte | word | ... ) [ expression (, expression)* ]
+bool MasmParser::parseDirectiveValue(StringRef IDVal, unsigned Size) {
+  auto parseOp = [&]() -> bool {
+    const MCExpr *Value;
+    SMLoc ExprLoc = getLexer().getLoc();
+    if (checkForValidSection() || parseExpression(Value))
+      return true;
+    // Special case constant expressions to match code generator.
+    if (const MCConstantExpr *MCE = dyn_cast<MCConstantExpr>(Value)) {
+      assert(Size <= 8 && "Invalid size");
+      int64_t IntValue = MCE->getValue();
+      if (!isUIntN(8 * Size, IntValue) && !isIntN(8 * Size, IntValue))
+        return Error(ExprLoc, "out of range literal value");
+      getStreamer().emitIntValue(IntValue, Size);
+    } else
+      getStreamer().emitValue(Value, Size, ExprLoc);
+    return false;
+  };
+
+  if (parseMany(parseOp))
+    return addErrorSuffix(" in '" + Twine(IDVal) + "' directive");
+  return false;
+}
+
+static bool parseHexOcta(MasmParser &Asm, uint64_t &hi, uint64_t &lo) {
+  if (Asm.getTok().isNot(AsmToken::Integer) &&
+      Asm.getTok().isNot(AsmToken::BigNum))
+    return Asm.TokError("unknown token in expression");
+  SMLoc ExprLoc = Asm.getTok().getLoc();
+  APInt IntValue = Asm.getTok().getAPIntVal();
+  Asm.Lex();
+  if (!IntValue.isIntN(128))
+    return Asm.Error(ExprLoc, "out of range literal value");
+  if (!IntValue.isIntN(64)) {
+    hi = IntValue.getHiBits(IntValue.getBitWidth() - 64).getZExtValue();
+    lo = IntValue.getLoBits(64).getZExtValue();
+  } else {
+    hi = 0;
+    lo = IntValue.getZExtValue();
+  }
+  return false;
+}
+
+bool MasmParser::parseRealValue(const fltSemantics &Semantics, APInt &Res) {
+  // We don't truly support arithmetic on floating point expressions, so we
+  // have to manually parse unary prefixes.
+  bool IsNeg = false;
+  if (getLexer().is(AsmToken::Minus)) {
+    Lexer.Lex();
+    IsNeg = true;
+  } else if (getLexer().is(AsmToken::Plus))
+    Lexer.Lex();
+
+  if (Lexer.is(AsmToken::Error))
+    return TokError(Lexer.getErr());
+  if (Lexer.isNot(AsmToken::Integer) && Lexer.isNot(AsmToken::Real) &&
+      Lexer.isNot(AsmToken::Identifier))
+    return TokError("unexpected token in directive");
+
+  // Convert to an APFloat.
+  APFloat Value(Semantics);
+  StringRef IDVal = getTok().getString();
+  if (getLexer().is(AsmToken::Identifier)) {
+    if (!IDVal.compare_lower("infinity") || !IDVal.compare_lower("inf"))
+      Value = APFloat::getInf(Semantics);
+    else if (!IDVal.compare_lower("nan"))
+      Value = APFloat::getNaN(Semantics, false, ~0);
+    else
+      return TokError("invalid floating point literal");
+  } else if (errorToBool(
+                 Value.convertFromString(IDVal, APFloat::rmNearestTiesToEven)
+                     .takeError()))
+    return TokError("invalid floating point literal");
+  if (IsNeg)
+    Value.changeSign();
+
+  // Consume the numeric token.
+  Lex();
+
+  Res = Value.bitcastToAPInt();
+
+  return false;
+}
+
+/// parseDirectiveRealValue
+///  ::= (real4 | real8) [ expression (, expression)* ]
+bool MasmParser::parseDirectiveRealValue(StringRef IDVal,
+                                         const fltSemantics &Semantics) {
+  auto parseOp = [&]() -> bool {
+    APInt AsInt;
+    if (checkForValidSection() || parseRealValue(Semantics, AsInt))
+      return true;
+    getStreamer().emitIntValue(AsInt.getLimitedValue(),
+                               AsInt.getBitWidth() / 8);
+    return false;
+  };
+
+  if (parseMany(parseOp))
+    return addErrorSuffix(" in '" + Twine(IDVal) + "' directive");
+  return false;
+}
+
+/// parseDirectiveOrg
+///  ::= .org expression [ , expression ]
+bool MasmParser::parseDirectiveOrg() {
+  const MCExpr *Offset;
+  SMLoc OffsetLoc = Lexer.getLoc();
+  if (checkForValidSection() || parseExpression(Offset))
+    return true;
+
+  // Parse optional fill expression.
+  int64_t FillExpr = 0;
+  if (parseOptionalToken(AsmToken::Comma))
+    if (parseAbsoluteExpression(FillExpr))
+      return addErrorSuffix(" in '.org' directive");
+  if (parseToken(AsmToken::EndOfStatement))
+    return addErrorSuffix(" in '.org' directive");
+
+  getStreamer().emitValueToOffset(Offset, FillExpr, OffsetLoc);
+  return false;
+}
+
+/// parseDirectiveAlign
+///  ::= align expression
+bool MasmParser::parseDirectiveAlign() {
+  SMLoc AlignmentLoc = getLexer().getLoc();
+  int64_t Alignment;
+
+  if (checkForValidSection())
+    return addErrorSuffix(" in align directive");
+  // Ignore empty 'align' directives
+  if (getTok().is(AsmToken::EndOfStatement)) {
+    Warning(AlignmentLoc, "align directive with no operand is ignored");
+    return parseToken(AsmToken::EndOfStatement);
+  }
+  if (parseAbsoluteExpression(Alignment) ||
+      parseToken(AsmToken::EndOfStatement))
+    return addErrorSuffix(" in align directive");
+
+  // Always emit an alignment here even if we thrown an error.
+  bool ReturnVal = false;
+
+  // Reject alignments that aren't either a power of two or zero,
+  // for gas compatibility. Alignment of zero is silently rounded
+  // up to one.
+  if (Alignment == 0)
+    Alignment = 1;
+  if (!isPowerOf2_64(Alignment))
+    ReturnVal |= Error(AlignmentLoc, "alignment must be a power of 2");
+
+  // Check whether we should use optimal code alignment for this align
+  // directive.
+  const MCSection *Section = getStreamer().getCurrentSectionOnly();
+  assert(Section && "must have section to emit alignment");
+  if (Section->UseCodeAlign()) {
+    getStreamer().emitCodeAlignment(Alignment, /*MaxBytesToEmit=*/0);
+  } else {
+    // FIXME: Target specific behavior about how the "extra" bytes are filled.
+    getStreamer().emitValueToAlignment(Alignment, /*Value=*/0, /*ValueSize=*/1,
+                                       /*MaxBytesToEmit=*/0);
+  }
+
+  return ReturnVal;
+}
+
+/// parseDirectiveFile
+/// ::= .file filename
+/// ::= .file number [directory] filename [md5 checksum] [source source-text]
+bool MasmParser::parseDirectiveFile(SMLoc DirectiveLoc) {
+  // FIXME: I'm not sure what this is.
+  int64_t FileNumber = -1;
+  if (getLexer().is(AsmToken::Integer)) {
+    FileNumber = getTok().getIntVal();
+    Lex();
+
+    if (FileNumber < 0)
+      return TokError("negative file number");
+  }
+
+  std::string Path;
+
+  // Usually the directory and filename together, otherwise just the directory.
+  // Allow the strings to have escaped octal character sequence.
+  if (check(getTok().isNot(AsmToken::String),
+            "unexpected token in '.file' directive") ||
+      parseEscapedString(Path))
+    return true;
+
+  StringRef Directory;
+  StringRef Filename;
+  std::string FilenameData;
+  if (getLexer().is(AsmToken::String)) {
+    if (check(FileNumber == -1,
+              "explicit path specified, but no file number") ||
+        parseEscapedString(FilenameData))
+      return true;
+    Filename = FilenameData;
+    Directory = Path;
+  } else {
+    Filename = Path;
+  }
+
+  uint64_t MD5Hi, MD5Lo;
+  bool HasMD5 = false;
+
+  Optional<StringRef> Source;
+  bool HasSource = false;
+  std::string SourceString;
+
+  while (!parseOptionalToken(AsmToken::EndOfStatement)) {
+    StringRef Keyword;
+    if (check(getTok().isNot(AsmToken::Identifier),
+              "unexpected token in '.file' directive") ||
+        parseIdentifier(Keyword))
+      return true;
+    if (Keyword == "md5") {
+      HasMD5 = true;
+      if (check(FileNumber == -1,
+                "MD5 checksum specified, but no file number") ||
+          parseHexOcta(*this, MD5Hi, MD5Lo))
+        return true;
+    } else if (Keyword == "source") {
+      HasSource = true;
+      if (check(FileNumber == -1,
+                "source specified, but no file number") ||
+          check(getTok().isNot(AsmToken::String),
+                "unexpected token in '.file' directive") ||
+          parseEscapedString(SourceString))
+        return true;
+    } else {
+      return TokError("unexpected token in '.file' directive");
+    }
+  }
+
+  if (FileNumber == -1) {
+    // Ignore the directive if there is no number and the target doesn't support
+    // numberless .file directives. This allows some portability of assembler
+    // between 
diff erent object file formats.
+    if (getContext().getAsmInfo()->hasSingleParameterDotFile())
+      getStreamer().emitFileDirective(Filename);
+  } else {
+    // In case there is a -g option as well as debug info from directive .file,
+    // we turn off the -g option, directly use the existing debug info instead.
+    // Throw away any implicit file table for the assembler source.
+    if (Ctx.getGenDwarfForAssembly()) {
+      Ctx.getMCDwarfLineTable(0).resetFileTable();
+      Ctx.setGenDwarfForAssembly(false);
+    }
+
+    Optional<MD5::MD5Result> CKMem;
+    if (HasMD5) {
+      MD5::MD5Result Sum;
+      for (unsigned i = 0; i != 8; ++i) {
+        Sum.Bytes[i] = uint8_t(MD5Hi >> ((7 - i) * 8));
+        Sum.Bytes[i + 8] = uint8_t(MD5Lo >> ((7 - i) * 8));
+      }
+      CKMem = Sum;
+    }
+    if (HasSource) {
+      char *SourceBuf = static_cast<char *>(Ctx.allocate(SourceString.size()));
+      memcpy(SourceBuf, SourceString.data(), SourceString.size());
+      Source = StringRef(SourceBuf, SourceString.size());
+    }
+    if (FileNumber == 0) {
+      if (Ctx.getDwarfVersion() < 5)
+        return Warning(DirectiveLoc, "file 0 not supported prior to DWARF-5");
+      getStreamer().emitDwarfFile0Directive(Directory, Filename, CKMem, Source);
+    } else {
+      Expected<unsigned> FileNumOrErr = getStreamer().tryEmitDwarfFileDirective(
+          FileNumber, Directory, Filename, CKMem, Source);
+      if (!FileNumOrErr)
+        return Error(DirectiveLoc, toString(FileNumOrErr.takeError()));
+    }
+    // Alert the user if there are some .file directives with MD5 and some not.
+    // But only do that once.
+    if (!ReportedInconsistentMD5 && !Ctx.isDwarfMD5UsageConsistent(0)) {
+      ReportedInconsistentMD5 = true;
+      return Warning(DirectiveLoc, "inconsistent use of MD5 checksums");
+    }
+  }
+
+  return false;
+}
+
+/// parseDirectiveLine
+/// ::= .line [number]
+bool MasmParser::parseDirectiveLine() {
+  int64_t LineNumber;
+  if (getLexer().is(AsmToken::Integer)) {
+    if (parseIntToken(LineNumber, "unexpected token in '.line' directive"))
+      return true;
+    (void)LineNumber;
+    // FIXME: Do something with the .line.
+  }
+  if (parseToken(AsmToken::EndOfStatement,
+                 "unexpected token in '.line' directive"))
+    return true;
+
+  return false;
+}
+
+/// parseDirectiveLoc
+/// ::= .loc FileNumber [LineNumber] [ColumnPos] [basic_block] [prologue_end]
+///                                [epilogue_begin] [is_stmt VALUE] [isa 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 MasmParser::parseDirectiveLoc() {
+  int64_t FileNumber = 0, LineNumber = 0;
+  SMLoc Loc = getTok().getLoc();
+  if (parseIntToken(FileNumber, "unexpected token in '.loc' directive") ||
+      check(FileNumber < 1 && Ctx.getDwarfVersion() < 5, Loc,
+            "file number less than one in '.loc' directive") ||
+      check(!getContext().isValidDwarfFileNumber(FileNumber), Loc,
+            "unassigned file number in '.loc' directive"))
+    return true;
+
+  // optional
+  if (getLexer().is(AsmToken::Integer)) {
+    LineNumber = getTok().getIntVal();
+    if (LineNumber < 0)
+      return TokError("line number less than zero in '.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 '.loc' directive");
+    Lex();
+  }
+
+  unsigned Flags = DWARF2_LINE_DEFAULT_IS_STMT ? DWARF2_FLAG_IS_STMT : 0;
+  unsigned Isa = 0;
+  int64_t Discriminator = 0;
+
+  auto parseLocOp = [&]() -> bool {
+    StringRef Name;
+    SMLoc Loc = getTok().getLoc();
+    if (parseIdentifier(Name))
+      return TokError("unexpected token in '.loc' directive");
+
+    if (Name == "basic_block")
+      Flags |= DWARF2_FLAG_BASIC_BLOCK;
+    else if (Name == "prologue_end")
+      Flags |= DWARF2_FLAG_PROLOGUE_END;
+    else if (Name == "epilogue_begin")
+      Flags |= DWARF2_FLAG_EPILOGUE_BEGIN;
+    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.
+      if (const MCConstantExpr *MCE = dyn_cast<MCConstantExpr>(Value)) {
+        int Value = MCE->getValue();
+        if (Value == 0)
+          Flags &= ~DWARF2_FLAG_IS_STMT;
+        else if (Value == 1)
+          Flags |= DWARF2_FLAG_IS_STMT;
+        else
+          return Error(Loc, "is_stmt value not 0 or 1");
+      } else {
+        return Error(Loc, "is_stmt value not the constant value of 0 or 1");
+      }
+    } else if (Name == "isa") {
+      Loc = getTok().getLoc();
+      const MCExpr *Value;
+      if (parseExpression(Value))
+        return true;
+      // The expression must be a constant greater or equal to 0.
+      if (const MCConstantExpr *MCE = dyn_cast<MCConstantExpr>(Value)) {
+        int Value = MCE->getValue();
+        if (Value < 0)
+          return Error(Loc, "isa number less than zero");
+        Isa = Value;
+      } else {
+        return Error(Loc, "isa number not a constant value");
+      }
+    } else if (Name == "discriminator") {
+      if (parseAbsoluteExpression(Discriminator))
+        return true;
+    } else {
+      return Error(Loc, "unknown sub-directive in '.loc' directive");
+    }
+    return false;
+  };
+
+  if (parseMany(parseLocOp, false /*hasComma*/))
+    return true;
+
+  getStreamer().emitDwarfLocDirective(FileNumber, LineNumber, ColumnPos, Flags,
+                                      Isa, Discriminator, StringRef());
+
+  return false;
+}
+
+/// parseDirectiveStabs
+/// ::= .stabs string, number, number, number
+bool MasmParser::parseDirectiveStabs() {
+  return TokError("unsupported directive '.stabs'");
+}
+
+/// parseDirectiveCVFile
+/// ::= .cv_file number filename [checksum] [checksumkind]
+bool MasmParser::parseDirectiveCVFile() {
+  SMLoc FileNumberLoc = getTok().getLoc();
+  int64_t FileNumber;
+  std::string Filename;
+  std::string Checksum;
+  int64_t ChecksumKind = 0;
+
+  if (parseIntToken(FileNumber,
+                    "expected file number in '.cv_file' directive") ||
+      check(FileNumber < 1, FileNumberLoc, "file number less than one") ||
+      check(getTok().isNot(AsmToken::String),
+            "unexpected token in '.cv_file' directive") ||
+      parseEscapedString(Filename))
+    return true;
+  if (!parseOptionalToken(AsmToken::EndOfStatement)) {
+    if (check(getTok().isNot(AsmToken::String),
+              "unexpected token in '.cv_file' directive") ||
+        parseEscapedString(Checksum) ||
+        parseIntToken(ChecksumKind,
+                      "expected checksum kind in '.cv_file' directive") ||
+        parseToken(AsmToken::EndOfStatement,
+                   "unexpected token in '.cv_file' directive"))
+      return true;
+  }
+
+  Checksum = fromHex(Checksum);
+  void *CKMem = Ctx.allocate(Checksum.size(), 1);
+  memcpy(CKMem, Checksum.data(), Checksum.size());
+  ArrayRef<uint8_t> ChecksumAsBytes(reinterpret_cast<const uint8_t *>(CKMem),
+                                    Checksum.size());
+
+  if (!getStreamer().EmitCVFileDirective(FileNumber, Filename, ChecksumAsBytes,
+                                         static_cast<uint8_t>(ChecksumKind)))
+    return Error(FileNumberLoc, "file number already allocated");
+
+  return false;
+}
+
+bool MasmParser::parseCVFunctionId(int64_t &FunctionId,
+                                   StringRef DirectiveName) {
+  SMLoc Loc;
+  return parseTokenLoc(Loc) ||
+         parseIntToken(FunctionId, "expected function id in '" + DirectiveName +
+                                       "' directive") ||
+         check(FunctionId < 0 || FunctionId >= UINT_MAX, Loc,
+               "expected function id within range [0, UINT_MAX)");
+}
+
+bool MasmParser::parseCVFileId(int64_t &FileNumber, StringRef DirectiveName) {
+  SMLoc Loc;
+  return parseTokenLoc(Loc) ||
+         parseIntToken(FileNumber, "expected integer in '" + DirectiveName +
+                                       "' directive") ||
+         check(FileNumber < 1, Loc, "file number less than one in '" +
+                                        DirectiveName + "' directive") ||
+         check(!getCVContext().isValidFileNumber(FileNumber), Loc,
+               "unassigned file number in '" + DirectiveName + "' directive");
+}
+
+/// parseDirectiveCVFuncId
+/// ::= .cv_func_id FunctionId
+///
+/// Introduces a function ID that can be used with .cv_loc.
+bool MasmParser::parseDirectiveCVFuncId() {
+  SMLoc FunctionIdLoc = getTok().getLoc();
+  int64_t FunctionId;
+
+  if (parseCVFunctionId(FunctionId, ".cv_func_id") ||
+      parseToken(AsmToken::EndOfStatement,
+                 "unexpected token in '.cv_func_id' directive"))
+    return true;
+
+  if (!getStreamer().EmitCVFuncIdDirective(FunctionId))
+    return Error(FunctionIdLoc, "function id already allocated");
+
+  return false;
+}
+
+/// parseDirectiveCVInlineSiteId
+/// ::= .cv_inline_site_id FunctionId
+///         "within" IAFunc
+///         "inlined_at" IAFile IALine [IACol]
+///
+/// Introduces a function ID that can be used with .cv_loc. Includes "inlined
+/// at" source location information for use in the line table of the caller,
+/// whether the caller is a real function or another inlined call site.
+bool MasmParser::parseDirectiveCVInlineSiteId() {
+  SMLoc FunctionIdLoc = getTok().getLoc();
+  int64_t FunctionId;
+  int64_t IAFunc;
+  int64_t IAFile;
+  int64_t IALine;
+  int64_t IACol = 0;
+
+  // FunctionId
+  if (parseCVFunctionId(FunctionId, ".cv_inline_site_id"))
+    return true;
+
+  // "within"
+  if (check((getLexer().isNot(AsmToken::Identifier) ||
+             getTok().getIdentifier() != "within"),
+            "expected 'within' identifier in '.cv_inline_site_id' directive"))
+    return true;
+  Lex();
+
+  // IAFunc
+  if (parseCVFunctionId(IAFunc, ".cv_inline_site_id"))
+    return true;
+
+  // "inlined_at"
+  if (check((getLexer().isNot(AsmToken::Identifier) ||
+             getTok().getIdentifier() != "inlined_at"),
+            "expected 'inlined_at' identifier in '.cv_inline_site_id' "
+            "directive") )
+    return true;
+  Lex();
+
+  // IAFile IALine
+  if (parseCVFileId(IAFile, ".cv_inline_site_id") ||
+      parseIntToken(IALine, "expected line number after 'inlined_at'"))
+    return true;
+
+  // [IACol]
+  if (getLexer().is(AsmToken::Integer)) {
+    IACol = getTok().getIntVal();
+    Lex();
+  }
+
+  if (parseToken(AsmToken::EndOfStatement,
+                 "unexpected token in '.cv_inline_site_id' directive"))
+    return true;
+
+  if (!getStreamer().EmitCVInlineSiteIdDirective(FunctionId, IAFunc, IAFile,
+                                                 IALine, IACol, FunctionIdLoc))
+    return Error(FunctionIdLoc, "function id 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 MasmParser::parseDirectiveCVLoc() {
+  SMLoc DirectiveLoc = getTok().getLoc();
+  int64_t FunctionId, FileNumber;
+  if (parseCVFunctionId(FunctionId, ".cv_loc") ||
+      parseCVFileId(FileNumber, ".cv_loc"))
+    return true;
+
+  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;
+
+  auto parseOp = [&]() -> bool {
+    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");
+    }
+    return false;
+  };
+
+  if (parseMany(parseOp, false /*hasComma*/))
+    return true;
+
+  getStreamer().EmitCVLocDirective(FunctionId, FileNumber, LineNumber,
+                                   ColumnPos, PrologueEnd, IsStmt, StringRef(),
+                                   DirectiveLoc);
+  return false;
+}
+
+/// parseDirectiveCVLinetable
+/// ::= .cv_linetable FunctionId, FnStart, FnEnd
+bool MasmParser::parseDirectiveCVLinetable() {
+  int64_t FunctionId;
+  StringRef FnStartName, FnEndName;
+  SMLoc Loc = getTok().getLoc();
+  if (parseCVFunctionId(FunctionId, ".cv_linetable") ||
+      parseToken(AsmToken::Comma,
+                 "unexpected token in '.cv_linetable' directive") ||
+      parseTokenLoc(Loc) || check(parseIdentifier(FnStartName), Loc,
+                                  "expected identifier in directive") ||
+      parseToken(AsmToken::Comma,
+                 "unexpected token in '.cv_linetable' directive") ||
+      parseTokenLoc(Loc) || check(parseIdentifier(FnEndName), Loc,
+                                  "expected identifier in directive"))
+    return true;
+
+  MCSymbol *FnStartSym = getContext().getOrCreateSymbol(FnStartName);
+  MCSymbol *FnEndSym = getContext().getOrCreateSymbol(FnEndName);
+
+  getStreamer().EmitCVLinetableDirective(FunctionId, FnStartSym, FnEndSym);
+  return false;
+}
+
+/// parseDirectiveCVInlineLinetable
+/// ::= .cv_inline_linetable PrimaryFunctionId FileId LineNum FnStart FnEnd
+bool MasmParser::parseDirectiveCVInlineLinetable() {
+  int64_t PrimaryFunctionId, SourceFileId, SourceLineNum;
+  StringRef FnStartName, FnEndName;
+  SMLoc Loc = getTok().getLoc();
+  if (parseCVFunctionId(PrimaryFunctionId, ".cv_inline_linetable") ||
+      parseTokenLoc(Loc) ||
+      parseIntToken(
+          SourceFileId,
+          "expected SourceField in '.cv_inline_linetable' directive") ||
+      check(SourceFileId <= 0, Loc,
+            "File id less than zero in '.cv_inline_linetable' directive") ||
+      parseTokenLoc(Loc) ||
+      parseIntToken(
+          SourceLineNum,
+          "expected SourceLineNum in '.cv_inline_linetable' directive") ||
+      check(SourceLineNum < 0, Loc,
+            "Line number less than zero in '.cv_inline_linetable' directive") ||
+      parseTokenLoc(Loc) || check(parseIdentifier(FnStartName), Loc,
+                                  "expected identifier in directive") ||
+      parseTokenLoc(Loc) || check(parseIdentifier(FnEndName), Loc,
+                                  "expected identifier in directive"))
+    return true;
+
+  if (parseToken(AsmToken::EndOfStatement, "Expected End of Statement"))
+    return true;
+
+  MCSymbol *FnStartSym = getContext().getOrCreateSymbol(FnStartName);
+  MCSymbol *FnEndSym = getContext().getOrCreateSymbol(FnEndName);
+  getStreamer().EmitCVInlineLinetableDirective(PrimaryFunctionId, SourceFileId,
+                                               SourceLineNum, FnStartSym,
+                                               FnEndSym);
+  return false;
+}
+
+void MasmParser::initializeCVDefRangeTypeMap() {
+  CVDefRangeTypeMap["reg"] = CVDR_DEFRANGE_REGISTER;
+  CVDefRangeTypeMap["frame_ptr_rel"] = CVDR_DEFRANGE_FRAMEPOINTER_REL;
+  CVDefRangeTypeMap["subfield_reg"] = CVDR_DEFRANGE_SUBFIELD_REGISTER;
+  CVDefRangeTypeMap["reg_rel"] = CVDR_DEFRANGE_REGISTER_REL;
+}
+
+/// parseDirectiveCVDefRange
+/// ::= .cv_def_range RangeStart RangeEnd (GapStart GapEnd)*, bytes*
+bool MasmParser::parseDirectiveCVDefRange() {
+  SMLoc Loc;
+  std::vector<std::pair<const MCSymbol *, const MCSymbol *>> Ranges;
+  while (getLexer().is(AsmToken::Identifier)) {
+    Loc = getLexer().getLoc();
+    StringRef GapStartName;
+    if (parseIdentifier(GapStartName))
+      return Error(Loc, "expected identifier in directive");
+    MCSymbol *GapStartSym = getContext().getOrCreateSymbol(GapStartName);
+
+    Loc = getLexer().getLoc();
+    StringRef GapEndName;
+    if (parseIdentifier(GapEndName))
+      return Error(Loc, "expected identifier in directive");
+    MCSymbol *GapEndSym = getContext().getOrCreateSymbol(GapEndName);
+
+    Ranges.push_back({GapStartSym, GapEndSym});
+  }
+
+  StringRef CVDefRangeTypeStr;
+  if (parseToken(
+          AsmToken::Comma,
+          "expected comma before def_range type in .cv_def_range directive") ||
+      parseIdentifier(CVDefRangeTypeStr))
+    return Error(Loc, "expected def_range type in directive");
+
+  StringMap<CVDefRangeType>::const_iterator CVTypeIt =
+      CVDefRangeTypeMap.find(CVDefRangeTypeStr);
+  CVDefRangeType CVDRType = (CVTypeIt == CVDefRangeTypeMap.end())
+                                ? CVDR_DEFRANGE
+                                : CVTypeIt->getValue();
+  switch (CVDRType) {
+  case CVDR_DEFRANGE_REGISTER: {
+    int64_t DRRegister;
+    if (parseToken(AsmToken::Comma, "expected comma before register number in "
+                                    ".cv_def_range directive") ||
+        parseAbsoluteExpression(DRRegister))
+      return Error(Loc, "expected register number");
+
+    codeview::DefRangeRegisterHeader DRHdr;
+    DRHdr.Register = DRRegister;
+    DRHdr.MayHaveNoName = 0;
+    getStreamer().EmitCVDefRangeDirective(Ranges, DRHdr);
+    break;
+  }
+  case CVDR_DEFRANGE_FRAMEPOINTER_REL: {
+    int64_t DROffset;
+    if (parseToken(AsmToken::Comma,
+                   "expected comma before offset in .cv_def_range directive") ||
+        parseAbsoluteExpression(DROffset))
+      return Error(Loc, "expected offset value");
+
+    codeview::DefRangeFramePointerRelHeader DRHdr;
+    DRHdr.Offset = DROffset;
+    getStreamer().EmitCVDefRangeDirective(Ranges, DRHdr);
+    break;
+  }
+  case CVDR_DEFRANGE_SUBFIELD_REGISTER: {
+    int64_t DRRegister;
+    int64_t DROffsetInParent;
+    if (parseToken(AsmToken::Comma, "expected comma before register number in "
+                                    ".cv_def_range directive") ||
+        parseAbsoluteExpression(DRRegister))
+      return Error(Loc, "expected register number");
+    if (parseToken(AsmToken::Comma,
+                   "expected comma before offset in .cv_def_range directive") ||
+        parseAbsoluteExpression(DROffsetInParent))
+      return Error(Loc, "expected offset value");
+
+    codeview::DefRangeSubfieldRegisterHeader DRHdr;
+    DRHdr.Register = DRRegister;
+    DRHdr.MayHaveNoName = 0;
+    DRHdr.OffsetInParent = DROffsetInParent;
+    getStreamer().EmitCVDefRangeDirective(Ranges, DRHdr);
+    break;
+  }
+  case CVDR_DEFRANGE_REGISTER_REL: {
+    int64_t DRRegister;
+    int64_t DRFlags;
+    int64_t DRBasePointerOffset;
+    if (parseToken(AsmToken::Comma, "expected comma before register number in "
+                                    ".cv_def_range directive") ||
+        parseAbsoluteExpression(DRRegister))
+      return Error(Loc, "expected register value");
+    if (parseToken(
+            AsmToken::Comma,
+            "expected comma before flag value in .cv_def_range directive") ||
+        parseAbsoluteExpression(DRFlags))
+      return Error(Loc, "expected flag value");
+    if (parseToken(AsmToken::Comma, "expected comma before base pointer offset "
+                                    "in .cv_def_range directive") ||
+        parseAbsoluteExpression(DRBasePointerOffset))
+      return Error(Loc, "expected base pointer offset value");
+
+    codeview::DefRangeRegisterRelHeader DRHdr;
+    DRHdr.Register = DRRegister;
+    DRHdr.Flags = DRFlags;
+    DRHdr.BasePointerOffset = DRBasePointerOffset;
+    getStreamer().EmitCVDefRangeDirective(Ranges, DRHdr);
+    break;
+  }
+  default:
+    return Error(Loc, "unexpected def_range type in .cv_def_range directive");
+  }
+  return true;
+}
+
+/// parseDirectiveCVString
+/// ::= .cv_stringtable "string"
+bool MasmParser::parseDirectiveCVString() {
+  std::string Data;
+  if (checkForValidSection() || parseEscapedString(Data))
+    return addErrorSuffix(" in '.cv_string' directive");
+
+  // Put the string in the table and emit the offset.
+  std::pair<StringRef, unsigned> Insertion =
+      getCVContext().addToStringTable(Data);
+  getStreamer().emitIntValue(Insertion.second, 4);
+  return false;
+}
+
+/// parseDirectiveCVStringTable
+/// ::= .cv_stringtable
+bool MasmParser::parseDirectiveCVStringTable() {
+  getStreamer().EmitCVStringTableDirective();
+  return false;
+}
+
+/// parseDirectiveCVFileChecksums
+/// ::= .cv_filechecksums
+bool MasmParser::parseDirectiveCVFileChecksums() {
+  getStreamer().EmitCVFileChecksumsDirective();
+  return false;
+}
+
+/// parseDirectiveCVFileChecksumOffset
+/// ::= .cv_filechecksumoffset fileno
+bool MasmParser::parseDirectiveCVFileChecksumOffset() {
+  int64_t FileNo;
+  if (parseIntToken(FileNo, "expected identifier in directive"))
+    return true;
+  if (parseToken(AsmToken::EndOfStatement, "Expected End of Statement"))
+    return true;
+  getStreamer().EmitCVFileChecksumOffsetDirective(FileNo);
+  return false;
+}
+
+/// parseDirectiveCVFPOData
+/// ::= .cv_fpo_data procsym
+bool MasmParser::parseDirectiveCVFPOData() {
+  SMLoc DirLoc = getLexer().getLoc();
+  StringRef ProcName;
+  if (parseIdentifier(ProcName))
+    return TokError("expected symbol name");
+  if (parseEOL("unexpected tokens"))
+    return addErrorSuffix(" in '.cv_fpo_data' directive");
+  MCSymbol *ProcSym = getContext().getOrCreateSymbol(ProcName);
+  getStreamer().EmitCVFPOData(ProcSym, DirLoc);
+  return false;
+}
+
+/// parseDirectiveCFISections
+/// ::= .cfi_sections section [, section]
+bool MasmParser::parseDirectiveCFISections() {
+  StringRef Name;
+  bool EH = false;
+  bool Debug = false;
+
+  if (parseIdentifier(Name))
+    return TokError("Expected an identifier");
+
+  if (Name == ".eh_frame")
+    EH = true;
+  else if (Name == ".debug_frame")
+    Debug = true;
+
+  if (getLexer().is(AsmToken::Comma)) {
+    Lex();
+
+    if (parseIdentifier(Name))
+      return TokError("Expected an identifier");
+
+    if (Name == ".eh_frame")
+      EH = true;
+    else if (Name == ".debug_frame")
+      Debug = true;
+  }
+
+  getStreamer().emitCFISections(EH, Debug);
+  return false;
+}
+
+/// parseDirectiveCFIStartProc
+/// ::= .cfi_startproc [simple]
+bool MasmParser::parseDirectiveCFIStartProc() {
+  StringRef Simple;
+  if (!parseOptionalToken(AsmToken::EndOfStatement)) {
+    if (check(parseIdentifier(Simple) || Simple != "simple",
+              "unexpected token") ||
+        parseToken(AsmToken::EndOfStatement))
+      return addErrorSuffix(" in '.cfi_startproc' directive");
+  }
+
+  // TODO(kristina): Deal with a corner case of incorrect diagnostic context
+  // being produced if this directive is emitted as part of preprocessor macro
+  // expansion which can *ONLY* happen if Clang's cc1as is the API consumer.
+  // Tools like llvm-mc on the other hand are not affected by it, and report
+  // correct context information.
+  getStreamer().emitCFIStartProc(!Simple.empty(), Lexer.getLoc());
+  return false;
+}
+
+/// parseDirectiveCFIEndProc
+/// ::= .cfi_endproc
+bool MasmParser::parseDirectiveCFIEndProc() {
+  getStreamer().emitCFIEndProc();
+  return false;
+}
+
+/// parse register name or number.
+bool MasmParser::parseRegisterOrRegisterNumber(int64_t &Register,
+                                               SMLoc DirectiveLoc) {
+  unsigned RegNo;
+
+  if (getLexer().isNot(AsmToken::Integer)) {
+    if (getTargetParser().ParseRegister(RegNo, DirectiveLoc, DirectiveLoc))
+      return true;
+    Register = getContext().getRegisterInfo()->getDwarfRegNum(RegNo, true);
+  } else
+    return parseAbsoluteExpression(Register);
+
+  return false;
+}
+
+/// parseDirectiveCFIDefCfa
+/// ::= .cfi_def_cfa register,  offset
+bool MasmParser::parseDirectiveCFIDefCfa(SMLoc DirectiveLoc) {
+  int64_t Register = 0, Offset = 0;
+  if (parseRegisterOrRegisterNumber(Register, DirectiveLoc) ||
+      parseToken(AsmToken::Comma, "unexpected token in directive") ||
+      parseAbsoluteExpression(Offset))
+    return true;
+
+  getStreamer().emitCFIDefCfa(Register, Offset);
+  return false;
+}
+
+/// parseDirectiveCFIDefCfaOffset
+/// ::= .cfi_def_cfa_offset offset
+bool MasmParser::parseDirectiveCFIDefCfaOffset() {
+  int64_t Offset = 0;
+  if (parseAbsoluteExpression(Offset))
+    return true;
+
+  getStreamer().emitCFIDefCfaOffset(Offset);
+  return false;
+}
+
+/// parseDirectiveCFIRegister
+/// ::= .cfi_register register, register
+bool MasmParser::parseDirectiveCFIRegister(SMLoc DirectiveLoc) {
+  int64_t Register1 = 0, Register2 = 0;
+  if (parseRegisterOrRegisterNumber(Register1, DirectiveLoc) ||
+      parseToken(AsmToken::Comma, "unexpected token in directive") ||
+      parseRegisterOrRegisterNumber(Register2, DirectiveLoc))
+    return true;
+
+  getStreamer().emitCFIRegister(Register1, Register2);
+  return false;
+}
+
+/// parseDirectiveCFIWindowSave
+/// ::= .cfi_window_save
+bool MasmParser::parseDirectiveCFIWindowSave() {
+  getStreamer().emitCFIWindowSave();
+  return false;
+}
+
+/// parseDirectiveCFIAdjustCfaOffset
+/// ::= .cfi_adjust_cfa_offset adjustment
+bool MasmParser::parseDirectiveCFIAdjustCfaOffset() {
+  int64_t Adjustment = 0;
+  if (parseAbsoluteExpression(Adjustment))
+    return true;
+
+  getStreamer().emitCFIAdjustCfaOffset(Adjustment);
+  return false;
+}
+
+/// parseDirectiveCFIDefCfaRegister
+/// ::= .cfi_def_cfa_register register
+bool MasmParser::parseDirectiveCFIDefCfaRegister(SMLoc DirectiveLoc) {
+  int64_t Register = 0;
+  if (parseRegisterOrRegisterNumber(Register, DirectiveLoc))
+    return true;
+
+  getStreamer().emitCFIDefCfaRegister(Register);
+  return false;
+}
+
+/// parseDirectiveCFIOffset
+/// ::= .cfi_offset register, offset
+bool MasmParser::parseDirectiveCFIOffset(SMLoc DirectiveLoc) {
+  int64_t Register = 0;
+  int64_t Offset = 0;
+
+  if (parseRegisterOrRegisterNumber(Register, DirectiveLoc) ||
+      parseToken(AsmToken::Comma, "unexpected token in directive") ||
+      parseAbsoluteExpression(Offset))
+    return true;
+
+  getStreamer().emitCFIOffset(Register, Offset);
+  return false;
+}
+
+/// parseDirectiveCFIRelOffset
+/// ::= .cfi_rel_offset register, offset
+bool MasmParser::parseDirectiveCFIRelOffset(SMLoc DirectiveLoc) {
+  int64_t Register = 0, Offset = 0;
+
+  if (parseRegisterOrRegisterNumber(Register, DirectiveLoc) ||
+      parseToken(AsmToken::Comma, "unexpected token in directive") ||
+      parseAbsoluteExpression(Offset))
+    return true;
+
+  getStreamer().emitCFIRelOffset(Register, Offset);
+  return false;
+}
+
+static bool isValidEncoding(int64_t Encoding) {
+  if (Encoding & ~0xff)
+    return false;
+
+  if (Encoding == dwarf::DW_EH_PE_omit)
+    return true;
+
+  const unsigned Format = Encoding & 0xf;
+  if (Format != dwarf::DW_EH_PE_absptr && Format != dwarf::DW_EH_PE_udata2 &&
+      Format != dwarf::DW_EH_PE_udata4 && Format != dwarf::DW_EH_PE_udata8 &&
+      Format != dwarf::DW_EH_PE_sdata2 && Format != dwarf::DW_EH_PE_sdata4 &&
+      Format != dwarf::DW_EH_PE_sdata8 && Format != dwarf::DW_EH_PE_signed)
+    return false;
+
+  const unsigned Application = Encoding & 0x70;
+  if (Application != dwarf::DW_EH_PE_absptr &&
+      Application != dwarf::DW_EH_PE_pcrel)
+    return false;
+
+  return true;
+}
+
+/// parseDirectiveCFIPersonalityOrLsda
+/// IsPersonality true for cfi_personality, false for cfi_lsda
+/// ::= .cfi_personality encoding, [symbol_name]
+/// ::= .cfi_lsda encoding, [symbol_name]
+bool MasmParser::parseDirectiveCFIPersonalityOrLsda(bool IsPersonality) {
+  int64_t Encoding = 0;
+  if (parseAbsoluteExpression(Encoding))
+    return true;
+  if (Encoding == dwarf::DW_EH_PE_omit)
+    return false;
+
+  StringRef Name;
+  if (check(!isValidEncoding(Encoding), "unsupported encoding.") ||
+      parseToken(AsmToken::Comma, "unexpected token in directive") ||
+      check(parseIdentifier(Name), "expected identifier in directive"))
+    return true;
+
+  MCSymbol *Sym = getContext().getOrCreateSymbol(Name);
+
+  if (IsPersonality)
+    getStreamer().emitCFIPersonality(Sym, Encoding);
+  else
+    getStreamer().emitCFILsda(Sym, Encoding);
+  return false;
+}
+
+/// parseDirectiveCFIRememberState
+/// ::= .cfi_remember_state
+bool MasmParser::parseDirectiveCFIRememberState() {
+  getStreamer().emitCFIRememberState();
+  return false;
+}
+
+/// parseDirectiveCFIRestoreState
+/// ::= .cfi_remember_state
+bool MasmParser::parseDirectiveCFIRestoreState() {
+  getStreamer().emitCFIRestoreState();
+  return false;
+}
+
+/// parseDirectiveCFISameValue
+/// ::= .cfi_same_value register
+bool MasmParser::parseDirectiveCFISameValue(SMLoc DirectiveLoc) {
+  int64_t Register = 0;
+
+  if (parseRegisterOrRegisterNumber(Register, DirectiveLoc))
+    return true;
+
+  getStreamer().emitCFISameValue(Register);
+  return false;
+}
+
+/// parseDirectiveCFIRestore
+/// ::= .cfi_restore register
+bool MasmParser::parseDirectiveCFIRestore(SMLoc DirectiveLoc) {
+  int64_t Register = 0;
+  if (parseRegisterOrRegisterNumber(Register, DirectiveLoc))
+    return true;
+
+  getStreamer().emitCFIRestore(Register);
+  return false;
+}
+
+/// parseDirectiveCFIEscape
+/// ::= .cfi_escape expression[,...]
+bool MasmParser::parseDirectiveCFIEscape() {
+  std::string Values;
+  int64_t CurrValue;
+  if (parseAbsoluteExpression(CurrValue))
+    return true;
+
+  Values.push_back((uint8_t)CurrValue);
+
+  while (getLexer().is(AsmToken::Comma)) {
+    Lex();
+
+    if (parseAbsoluteExpression(CurrValue))
+      return true;
+
+    Values.push_back((uint8_t)CurrValue);
+  }
+
+  getStreamer().emitCFIEscape(Values);
+  return false;
+}
+
+/// parseDirectiveCFIReturnColumn
+/// ::= .cfi_return_column register
+bool MasmParser::parseDirectiveCFIReturnColumn(SMLoc DirectiveLoc) {
+  int64_t Register = 0;
+  if (parseRegisterOrRegisterNumber(Register, DirectiveLoc))
+    return true;
+  getStreamer().emitCFIReturnColumn(Register);
+  return false;
+}
+
+/// parseDirectiveCFISignalFrame
+/// ::= .cfi_signal_frame
+bool MasmParser::parseDirectiveCFISignalFrame() {
+  if (parseToken(AsmToken::EndOfStatement,
+                 "unexpected token in '.cfi_signal_frame'"))
+    return true;
+
+  getStreamer().emitCFISignalFrame();
+  return false;
+}
+
+/// parseDirectiveCFIUndefined
+/// ::= .cfi_undefined register
+bool MasmParser::parseDirectiveCFIUndefined(SMLoc DirectiveLoc) {
+  int64_t Register = 0;
+
+  if (parseRegisterOrRegisterNumber(Register, DirectiveLoc))
+    return true;
+
+  getStreamer().emitCFIUndefined(Register);
+  return false;
+}
+
+/// parseDirectiveAltmacro
+/// ::= .altmacro
+/// ::= .noaltmacro
+bool MasmParser::parseDirectiveAltmacro(StringRef Directive) {
+  if (getLexer().isNot(AsmToken::EndOfStatement))
+    return TokError("unexpected token in '" + Directive + "' directive");
+  AltMacroMode = (Directive == ".altmacro");
+  return false;
+}
+
+/// parseDirectiveMacrosOnOff
+/// ::= .macros_on
+/// ::= .macros_off
+bool MasmParser::parseDirectiveMacrosOnOff(StringRef Directive) {
+  if (parseToken(AsmToken::EndOfStatement,
+                 "unexpected token in '" + Directive + "' directive"))
+    return true;
+
+  setMacrosEnabled(Directive == ".macros_on");
+  return false;
+}
+
+/// parseDirectiveMacro
+/// ::= .macro name[,] [parameters]
+bool MasmParser::parseDirectiveMacro(SMLoc DirectiveLoc) {
+  StringRef Name;
+  if (parseIdentifier(Name))
+    return TokError("expected identifier in '.macro' directive");
+
+  if (getLexer().is(AsmToken::Comma))
+    Lex();
+
+  MCAsmMacroParameters Parameters;
+  while (getLexer().isNot(AsmToken::EndOfStatement)) {
+
+    if (!Parameters.empty() && Parameters.back().Vararg)
+      return Error(Lexer.getLoc(),
+                   "Vararg parameter '" + Parameters.back().Name +
+                   "' should be last one in the list of parameters.");
+
+    MCAsmMacroParameter Parameter;
+    if (parseIdentifier(Parameter.Name))
+      return TokError("expected identifier in '.macro' directive");
+
+    // Emit an error if two (or more) named parameters share the same name
+    for (const MCAsmMacroParameter& CurrParam : Parameters)
+      if (CurrParam.Name.equals(Parameter.Name))
+        return TokError("macro '" + Name + "' has multiple parameters"
+                        " named '" + Parameter.Name + "'");
+
+    if (Lexer.is(AsmToken::Colon)) {
+      Lex();  // consume ':'
+
+      SMLoc QualLoc;
+      StringRef Qualifier;
+
+      QualLoc = Lexer.getLoc();
+      if (parseIdentifier(Qualifier))
+        return Error(QualLoc, "missing parameter qualifier for "
+                     "'" + Parameter.Name + "' in macro '" + Name + "'");
+
+      if (Qualifier == "req")
+        Parameter.Required = true;
+      else if (Qualifier == "vararg")
+        Parameter.Vararg = true;
+      else
+        return Error(QualLoc, Qualifier + " is not a valid parameter qualifier "
+                     "for '" + Parameter.Name + "' in macro '" + Name + "'");
+    }
+
+    if (getLexer().is(AsmToken::Equal)) {
+      Lex();
+
+      SMLoc ParamLoc;
+
+      ParamLoc = Lexer.getLoc();
+      if (parseMacroArgument(Parameter.Value, /*Vararg=*/false ))
+        return true;
+
+      if (Parameter.Required)
+        Warning(ParamLoc, "pointless default value for required parameter "
+                "'" + Parameter.Name + "' in macro '" + Name + "'");
+    }
+
+    Parameters.push_back(std::move(Parameter));
+
+    if (getLexer().is(AsmToken::Comma))
+      Lex();
+  }
+
+  // Eat just the end of statement.
+  Lexer.Lex();
+
+  // Consuming deferred text, so use Lexer.Lex to ignore Lexing Errors
+  AsmToken EndToken, StartToken = getTok();
+  unsigned MacroDepth = 0;
+  // Lex the macro definition.
+  while (true) {
+    // Ignore Lexing errors in macros.
+    while (Lexer.is(AsmToken::Error)) {
+      Lexer.Lex();
+    }
+
+    // Check whether we have reached the end of the file.
+    if (getLexer().is(AsmToken::Eof))
+      return Error(DirectiveLoc, "no matching '.endmacro' in definition");
+
+    // Otherwise, check whether we have reach the .endmacro.
+    if (getLexer().is(AsmToken::Identifier)) {
+      if (getTok().getIdentifier() == ".endm" ||
+          getTok().getIdentifier() == ".endmacro") {
+        if (MacroDepth == 0) { // Outermost macro.
+          EndToken = getTok();
+          Lexer.Lex();
+          if (getLexer().isNot(AsmToken::EndOfStatement))
+            return TokError("unexpected token in '" + EndToken.getIdentifier() +
+                            "' directive");
+          break;
+        } else {
+          // Otherwise we just found the end of an inner macro.
+          --MacroDepth;
+        }
+      } else if (getTok().getIdentifier() == ".macro") {
+        // We allow nested macros. Those aren't instantiated until the outermost
+        // macro is expanded so just ignore them for now.
+        ++MacroDepth;
+      }
+    }
+
+    // Otherwise, scan til the end of the statement.
+    eatToEndOfStatement();
+  }
+
+  if (getContext().lookupMacro(Name)) {
+    return Error(DirectiveLoc, "macro '" + Name + "' is already defined");
+  }
+
+  const char *BodyStart = StartToken.getLoc().getPointer();
+  const char *BodyEnd = EndToken.getLoc().getPointer();
+  StringRef Body = StringRef(BodyStart, BodyEnd - BodyStart);
+  checkForBadMacro(DirectiveLoc, Name, Body, Parameters);
+  MCAsmMacro Macro(Name, Body, std::move(Parameters));
+  DEBUG_WITH_TYPE("asm-macros", dbgs() << "Defining new macro:\n";
+                  Macro.dump());
+  getContext().defineMacro(Name, std::move(Macro));
+  return false;
+}
+
+/// checkForBadMacro
+///
+/// With the support added for named parameters there may be code out there that
+/// is transitioning from positional parameters.  In versions of gas that did
+/// not support named parameters they would be ignored on the macro definition.
+/// But to support both styles of parameters this is not possible so if a macro
+/// definition has named parameters but does not use them and has what appears
+/// to be positional parameters, strings like $1, $2, ... and $n, then issue a
+/// warning that the positional parameter found in body which have no effect.
+/// Hoping the developer will either remove the named parameters from the macro
+/// definition so the positional parameters get used if that was what was
+/// intended or change the macro to use the named parameters.  It is possible
+/// this warning will trigger when the none of the named parameters are used
+/// and the strings like $1 are infact to simply to be passed trough unchanged.
+void MasmParser::checkForBadMacro(SMLoc DirectiveLoc, StringRef Name,
+                                  StringRef Body,
+                                  ArrayRef<MCAsmMacroParameter> Parameters) {
+  // If this macro is not defined with named parameters the warning we are
+  // checking for here doesn't apply.
+  unsigned NParameters = Parameters.size();
+  if (NParameters == 0)
+    return;
+
+  bool NamedParametersFound = false;
+  bool PositionalParametersFound = false;
+
+  // Look at the body of the macro for use of both the named parameters and what
+  // are likely to be positional parameters.  This is what expandMacro() is
+  // doing when it finds the parameters in the body.
+  while (!Body.empty()) {
+    // Scan for the next possible parameter.
+    std::size_t End = Body.size(), Pos = 0;
+    for (; Pos != End; ++Pos) {
+      // Check for a substitution or escape.
+      // This macro is defined with parameters, look for \foo, \bar, etc.
+      if (Body[Pos] == '\\' && Pos + 1 != End)
+        break;
+
+      // This macro should have parameters, but look for $0, $1, ..., $n too.
+      if (Body[Pos] != '$' || Pos + 1 == End)
+        continue;
+      char Next = Body[Pos + 1];
+      if (Next == '$' || Next == 'n' ||
+          isdigit(static_cast<unsigned char>(Next)))
+        break;
+    }
+
+    // Check if we reached the end.
+    if (Pos == End)
+      break;
+
+    if (Body[Pos] == '$') {
+      switch (Body[Pos + 1]) {
+      // $$ => $
+      case '$':
+        break;
+
+      // $n => number of arguments
+      case 'n':
+        PositionalParametersFound = true;
+        break;
+
+      // $[0-9] => argument
+      default: {
+        PositionalParametersFound = true;
+        break;
+      }
+      }
+      Pos += 2;
+    } else {
+      unsigned I = Pos + 1;
+      while (isIdentifierChar(Body[I]) && I + 1 != End)
+        ++I;
+
+      const char *Begin = Body.data() + Pos + 1;
+      StringRef Argument(Begin, I - (Pos + 1));
+      unsigned Index = 0;
+      for (; Index < NParameters; ++Index)
+        if (Parameters[Index].Name == Argument)
+          break;
+
+      if (Index == NParameters) {
+        if (Body[Pos + 1] == '(' && Body[Pos + 2] == ')')
+          Pos += 3;
+        else {
+          Pos = I;
+        }
+      } else {
+        NamedParametersFound = true;
+        Pos += 1 + Argument.size();
+      }
+    }
+    // Update the scan point.
+    Body = Body.substr(Pos);
+  }
+
+  if (!NamedParametersFound && PositionalParametersFound)
+    Warning(DirectiveLoc, "macro defined with named parameters which are not "
+                          "used in macro body, possible positional parameter "
+                          "found in body which will have no effect");
+}
+
+/// parseDirectiveExitMacro
+/// ::= .exitm
+bool MasmParser::parseDirectiveExitMacro(StringRef Directive) {
+  if (parseToken(AsmToken::EndOfStatement,
+                 "unexpected token in '" + Directive + "' directive"))
+    return true;
+
+  if (!isInsideMacroInstantiation())
+    return TokError("unexpected '" + Directive + "' in file, "
+                                                 "no current macro definition");
+
+  // Exit all conditionals that are active in the current macro.
+  while (TheCondStack.size() != ActiveMacros.back()->CondStackDepth) {
+    TheCondState = TheCondStack.back();
+    TheCondStack.pop_back();
+  }
+
+  handleMacroExit();
+  return false;
+}
+
+/// parseDirectiveEndMacro
+/// ::= .endm
+/// ::= .endmacro
+bool MasmParser::parseDirectiveEndMacro(StringRef Directive) {
+  if (getLexer().isNot(AsmToken::EndOfStatement))
+    return TokError("unexpected token in '" + Directive + "' directive");
+
+  // If we are inside a macro instantiation, terminate the current
+  // instantiation.
+  if (isInsideMacroInstantiation()) {
+    handleMacroExit();
+    return false;
+  }
+
+  // Otherwise, this .endmacro is a stray entry in the file; well formed
+  // .endmacro directives are handled during the macro definition parsing.
+  return TokError("unexpected '" + Directive + "' in file, "
+                                               "no current macro definition");
+}
+
+/// parseDirectivePurgeMacro
+/// ::= .purgem
+bool MasmParser::parseDirectivePurgeMacro(SMLoc DirectiveLoc) {
+  StringRef Name;
+  SMLoc Loc;
+  if (parseTokenLoc(Loc) ||
+      check(parseIdentifier(Name), Loc,
+            "expected identifier in '.purgem' directive") ||
+      parseToken(AsmToken::EndOfStatement,
+                 "unexpected token in '.purgem' directive"))
+    return true;
+
+  if (!getContext().lookupMacro(Name))
+    return Error(DirectiveLoc, "macro '" + Name + "' is not defined");
+
+  getContext().undefineMacro(Name);
+  DEBUG_WITH_TYPE("asm-macros", dbgs()
+                                    << "Un-defining macro: " << Name << "\n");
+  return false;
+}
+
+/// parseDirectiveSymbolAttribute
+///  ::= { ".globl", ".weak", ... } [ identifier ( , identifier )* ]
+bool MasmParser::parseDirectiveSymbolAttribute(MCSymbolAttr Attr) {
+  auto parseOp = [&]() -> bool {
+    StringRef Name;
+    SMLoc Loc = getTok().getLoc();
+    if (parseIdentifier(Name))
+      return Error(Loc, "expected identifier");
+    MCSymbol *Sym = getContext().getOrCreateSymbol(Name);
+
+    // Assembler local symbols don't make any sense here. Complain loudly.
+    if (Sym->isTemporary())
+      return Error(Loc, "non-local symbol required");
+
+    if (!getStreamer().emitSymbolAttribute(Sym, Attr))
+      return Error(Loc, "unable to emit symbol attribute");
+    return false;
+  };
+
+  if (parseMany(parseOp))
+    return addErrorSuffix(" in directive");
+  return false;
+}
+
+/// parseDirectiveComm
+///  ::= ( .comm | .lcomm ) identifier , size_expression [ , align_expression ]
+bool MasmParser::parseDirectiveComm(bool IsLocal) {
+  if (checkForValidSection())
+    return true;
+
+  SMLoc IDLoc = getLexer().getLoc();
+  StringRef Name;
+  if (parseIdentifier(Name))
+    return TokError("expected identifier in directive");
+
+  // Handle the identifier as the key symbol.
+  MCSymbol *Sym = getContext().getOrCreateSymbol(Name);
+
+  if (getLexer().isNot(AsmToken::Comma))
+    return TokError("unexpected token in directive");
+  Lex();
+
+  int64_t Size;
+  SMLoc SizeLoc = getLexer().getLoc();
+  if (parseAbsoluteExpression(Size))
+    return true;
+
+  int64_t Pow2Alignment = 0;
+  SMLoc Pow2AlignmentLoc;
+  if (getLexer().is(AsmToken::Comma)) {
+    Lex();
+    Pow2AlignmentLoc = getLexer().getLoc();
+    if (parseAbsoluteExpression(Pow2Alignment))
+      return true;
+
+    LCOMM::LCOMMType LCOMM = Lexer.getMAI().getLCOMMDirectiveAlignmentType();
+    if (IsLocal && LCOMM == LCOMM::NoAlignment)
+      return Error(Pow2AlignmentLoc, "alignment not supported on this target");
+
+    // If this target takes alignments in bytes (not log) validate and convert.
+    if ((!IsLocal && Lexer.getMAI().getCOMMDirectiveAlignmentIsInBytes()) ||
+        (IsLocal && LCOMM == LCOMM::ByteAlignment)) {
+      if (!isPowerOf2_64(Pow2Alignment))
+        return Error(Pow2AlignmentLoc, "alignment must be a power of 2");
+      Pow2Alignment = Log2_64(Pow2Alignment);
+    }
+  }
+
+  if (parseToken(AsmToken::EndOfStatement,
+                 "unexpected token in '.comm' or '.lcomm' directive"))
+    return true;
+
+  // NOTE: a size of zero for a .comm should create a undefined symbol
+  // but a size of .lcomm creates a bss symbol of size zero.
+  if (Size < 0)
+    return Error(SizeLoc, "invalid '.comm' or '.lcomm' directive size, can't "
+                          "be less than zero");
+
+  // NOTE: The alignment in the directive is a power of 2 value, the assembler
+  // may internally end up wanting an alignment in bytes.
+  // FIXME: Diagnose overflow.
+  if (Pow2Alignment < 0)
+    return Error(Pow2AlignmentLoc, "invalid '.comm' or '.lcomm' directive "
+                                   "alignment, can't be less than zero");
+
+  Sym->redefineIfPossible();
+  if (!Sym->isUndefined())
+    return Error(IDLoc, "invalid symbol redefinition");
+
+  // Create the Symbol as a common or local common with Size and Pow2Alignment
+  if (IsLocal) {
+    getStreamer().emitLocalCommonSymbol(Sym, Size, 1 << Pow2Alignment);
+    return false;
+  }
+
+  getStreamer().emitCommonSymbol(Sym, Size, 1 << Pow2Alignment);
+  return false;
+}
+
+/// parseDirectiveComment
+///  ::= comment delimiter [[text]]
+///              [[text]]
+///              [[text]] delimiter [[text]]
+bool MasmParser::parseDirectiveComment(SMLoc DirectiveLoc) {
+  StringRef FirstLine = parseStringToEndOfStatement();
+  size_t DelimiterEnd = FirstLine.find_first_of("\b\t\v\f\r\x1A ");
+  StringRef Delimiter = FirstLine.take_front(DelimiterEnd);
+  if (Delimiter.empty())
+    return Error(DirectiveLoc, "no delimiter in 'comment' directive");
+  do {
+    if (getTok().is(AsmToken::Eof))
+      return Error(DirectiveLoc, "unmatched delimiter in 'comment' directive");
+    Lex();  // eat end of statement
+  } while (!parseStringToEndOfStatement().contains(Delimiter));
+  return parseToken(AsmToken::EndOfStatement,
+                    "unexpected token in 'comment' directive");
+}
+
+/// parseDirectiveInclude
+///  ::= include <filename>
+///    | include filename
+bool MasmParser::parseDirectiveInclude() {
+  // Allow the strings to have escaped octal character sequence.
+  std::string Filename;
+  SMLoc IncludeLoc = getTok().getLoc();
+
+  if (!parseAngleBracketString(Filename))
+    Filename = parseStringToEndOfStatement().str();
+  if (check(!Filename.empty(), "missing filename in 'include' directive") ||
+      check(getTok().isNot(AsmToken::EndOfStatement),
+            "unexpected token in 'include' directive") ||
+      // Attempt to switch the lexer to the included file before consuming the
+      // end of statement to avoid losing it when we switch.
+      check(enterIncludeFile(Filename), IncludeLoc,
+            "Could not find include file '" + Filename + "'"))
+    return true;
+
+  return false;
+}
+
+/// parseDirectiveIf
+/// ::= .if{,eq,ge,gt,le,lt,ne} expression
+bool MasmParser::parseDirectiveIf(SMLoc DirectiveLoc, DirectiveKind DirKind) {
+  TheCondStack.push_back(TheCondState);
+  TheCondState.TheCond = AsmCond::IfCond;
+  if (TheCondState.Ignore) {
+    eatToEndOfStatement();
+  } else {
+    int64_t ExprValue;
+    if (parseAbsoluteExpression(ExprValue) ||
+        parseToken(AsmToken::EndOfStatement,
+                   "unexpected token in '.if' directive"))
+      return true;
+
+    switch (DirKind) {
+    default:
+      llvm_unreachable("unsupported directive");
+    case DK_IF:
+      break;
+    case DK_IFE:
+      ExprValue = ExprValue == 0;
+      break;
+    }
+
+    TheCondState.CondMet = ExprValue;
+    TheCondState.Ignore = !TheCondState.CondMet;
+  }
+
+  return false;
+}
+
+/// parseDirectiveIfb
+/// ::= .ifb string
+bool MasmParser::parseDirectiveIfb(SMLoc DirectiveLoc, bool ExpectBlank) {
+  TheCondStack.push_back(TheCondState);
+  TheCondState.TheCond = AsmCond::IfCond;
+
+  if (TheCondState.Ignore) {
+    eatToEndOfStatement();
+  } else {
+    std::string Str;
+    if (parseTextItem(Str))
+      return TokError("expected string parameter for 'ifb' directive");
+
+    if (parseToken(AsmToken::EndOfStatement,
+                   "unexpected token in 'ifb' directive"))
+      return true;
+
+    TheCondState.CondMet = ExpectBlank == Str.empty();
+    TheCondState.Ignore = !TheCondState.CondMet;
+  }
+
+  return false;
+}
+
+/// parseDirectiveIfidn
+///   ::= ifidn string1, string2
+bool MasmParser::parseDirectiveIfidn(SMLoc DirectiveLoc, bool ExpectEqual, bool CaseInsensitive) {
+  std::string String1, String2;
+
+  if (parseTextItem(String1)) {
+    if (ExpectEqual)
+      return TokError("expected string parameter for 'ifidn' directive");
+    return TokError("expected string parameter for 'ifdif' directive");
+  }
+
+  if (Lexer.isNot(AsmToken::Comma)) {
+    if (ExpectEqual)
+      return TokError(
+          "expected comma after first string for 'ifidn' directive");
+    return TokError("expected comma after first string for 'ifdif' directive");
+  }
+  Lex();
+
+  if (parseTextItem(String2)) {
+    if (ExpectEqual)
+      return TokError("expected string parameter for 'ifidn' directive");
+    return TokError("expected string parameter for 'ifdif' directive");
+  }
+
+  TheCondStack.push_back(TheCondState);
+  TheCondState.TheCond = AsmCond::IfCond;
+  if (CaseInsensitive)
+    TheCondState.CondMet =
+        ExpectEqual == (StringRef(String1).equals_lower(String2));
+  else
+    TheCondState.CondMet = ExpectEqual == (String1 == String2);
+  TheCondState.Ignore = !TheCondState.CondMet;
+
+  return false;
+}
+
+/// parseDirectiveIfdef
+/// ::= ifdef symbol
+///   | ifdef variable
+bool MasmParser::parseDirectiveIfdef(SMLoc DirectiveLoc, bool expect_defined) {
+  TheCondStack.push_back(TheCondState);
+  TheCondState.TheCond = AsmCond::IfCond;
+
+  if (TheCondState.Ignore) {
+    eatToEndOfStatement();
+  } else {
+    bool is_defined = false;
+    unsigned RegNo;
+    SMLoc StartLoc, EndLoc;
+    is_defined = (getTargetParser().tryParseRegister(
+                      RegNo, StartLoc, EndLoc) == MatchOperand_Success);
+    if (!is_defined) {
+      StringRef Name;
+      if (check(parseIdentifier(Name), "expected identifier after 'ifdef'") ||
+          parseToken(AsmToken::EndOfStatement, "unexpected token in 'ifdef'"))
+        return true;
+
+      if (Variables.find(Name) != Variables.end()) {
+        is_defined = true;
+      } else {
+        MCSymbol *Sym = getContext().lookupSymbol(Name);
+        is_defined = (Sym && !Sym->isUndefined(false));
+      }
+    }
+
+    TheCondState.CondMet = (is_defined == expect_defined);
+    TheCondState.Ignore = !TheCondState.CondMet;
+  }
+
+  return false;
+}
+
+/// parseDirectiveElseIf
+/// ::= elseif expression
+bool MasmParser::parseDirectiveElseIf(SMLoc DirectiveLoc,
+                                      DirectiveKind DirKind) {
+  if (TheCondState.TheCond != AsmCond::IfCond &&
+      TheCondState.TheCond != AsmCond::ElseIfCond)
+    return Error(DirectiveLoc, "Encountered a .elseif that doesn't follow an"
+                               " .if or  an .elseif");
+  TheCondState.TheCond = AsmCond::ElseIfCond;
+
+  bool LastIgnoreState = false;
+  if (!TheCondStack.empty())
+    LastIgnoreState = TheCondStack.back().Ignore;
+  if (LastIgnoreState || TheCondState.CondMet) {
+    TheCondState.Ignore = true;
+    eatToEndOfStatement();
+  } else {
+    int64_t ExprValue;
+    if (parseAbsoluteExpression(ExprValue))
+      return true;
+
+    if (parseToken(AsmToken::EndOfStatement,
+                   "unexpected token in '.elseif' directive"))
+      return true;
+
+    switch (DirKind) {
+    default:
+      llvm_unreachable("unsupported directive");
+    case DK_ELSEIF:
+      break;
+    case DK_ELSEIFE:
+      ExprValue = ExprValue == 0;
+      break;
+    }
+
+    TheCondState.CondMet = ExprValue;
+    TheCondState.Ignore = !TheCondState.CondMet;
+  }
+
+  return false;
+}
+
+/// parseDirectiveElseIfb
+/// ::= elseifb expression
+bool MasmParser::parseDirectiveElseIfb(SMLoc DirectiveLoc, bool ExpectBlank) {
+  if (TheCondState.TheCond != AsmCond::IfCond &&
+      TheCondState.TheCond != AsmCond::ElseIfCond)
+    return Error(DirectiveLoc, "Encountered an elseif that doesn't follow an"
+                               " if or an elseif");
+  TheCondState.TheCond = AsmCond::ElseIfCond;
+
+  bool LastIgnoreState = false;
+  if (!TheCondStack.empty())
+    LastIgnoreState = TheCondStack.back().Ignore;
+  if (LastIgnoreState || TheCondState.CondMet) {
+    TheCondState.Ignore = true;
+    eatToEndOfStatement();
+  } else {
+    std::string Str;
+    if (parseTextItem(Str))
+      return TokError("expected string parameter for 'elseifb' directive");
+
+    if (parseToken(AsmToken::EndOfStatement,
+                   "unexpected token in 'elseifb' directive"))
+      return true;
+
+    TheCondState.CondMet = ExpectBlank == Str.empty();
+    TheCondState.Ignore = !TheCondState.CondMet;
+  }
+
+  return false;
+}
+
+/// parseDirectiveElseIfdef
+/// ::= elseifdef symbol
+///   | elseifdef variable
+bool MasmParser::parseDirectiveElseIfdef(SMLoc DirectiveLoc,
+                                         bool expect_defined) {
+  if (TheCondState.TheCond != AsmCond::IfCond &&
+      TheCondState.TheCond != AsmCond::ElseIfCond)
+    return Error(DirectiveLoc, "Encountered an elseif that doesn't follow an"
+                               " if or an elseif");
+  TheCondState.TheCond = AsmCond::ElseIfCond;
+
+  bool LastIgnoreState = false;
+  if (!TheCondStack.empty())
+    LastIgnoreState = TheCondStack.back().Ignore;
+  if (LastIgnoreState || TheCondState.CondMet) {
+    TheCondState.Ignore = true;
+    eatToEndOfStatement();
+  } else {
+    bool is_defined = false;
+    unsigned RegNo;
+    SMLoc StartLoc, EndLoc;
+    is_defined = (getTargetParser().tryParseRegister(RegNo, StartLoc, EndLoc) ==
+                  MatchOperand_Success);
+    if (!is_defined) {
+      StringRef Name;
+      if (check(parseIdentifier(Name),
+                "expected identifier after 'elseifdef'") ||
+          parseToken(AsmToken::EndOfStatement,
+                     "unexpected token in 'elseifdef'"))
+        return true;
+
+      if (Variables.find(Name) != Variables.end()) {
+        is_defined = true;
+      } else {
+        MCSymbol *Sym = getContext().lookupSymbol(Name);
+        is_defined = (Sym && !Sym->isUndefined(false));
+      }
+    }
+
+    TheCondState.CondMet = (is_defined == expect_defined);
+    TheCondState.Ignore = !TheCondState.CondMet;
+  }
+
+  return false;
+}
+
+/// parseDirectiveElseIfidn
+/// ::= elseifidn string1, string2
+bool MasmParser::parseDirectiveElseIfidn(SMLoc DirectiveLoc, bool ExpectEqual,
+                                         bool CaseInsensitive) {
+  if (TheCondState.TheCond != AsmCond::IfCond &&
+      TheCondState.TheCond != AsmCond::ElseIfCond)
+    return Error(DirectiveLoc, "Encountered an elseif that doesn't follow an"
+                               " if or an elseif");
+  TheCondState.TheCond = AsmCond::ElseIfCond;
+
+  bool LastIgnoreState = false;
+  if (!TheCondStack.empty())
+    LastIgnoreState = TheCondStack.back().Ignore;
+  if (LastIgnoreState || TheCondState.CondMet) {
+    TheCondState.Ignore = true;
+    eatToEndOfStatement();
+  } else {
+    std::string String1, String2;
+
+    if (parseTextItem(String1)) {
+      if (ExpectEqual)
+        return TokError("expected string parameter for 'elseifidn' directive");
+      return TokError("expected string parameter for 'elseifdif' directive");
+    }
+
+    if (Lexer.isNot(AsmToken::Comma)) {
+      if (ExpectEqual)
+        return TokError(
+            "expected comma after first string for 'elseifidn' directive");
+      return TokError(
+          "expected comma after first string for 'elseifdif' directive");
+    }
+    Lex();
+
+    if (parseTextItem(String2)) {
+      if (ExpectEqual)
+        return TokError("expected string parameter for 'elseifidn' directive");
+      return TokError("expected string parameter for 'elseifdif' directive");
+    }
+
+    if (CaseInsensitive)
+      TheCondState.CondMet =
+          ExpectEqual == (StringRef(String1).equals_lower(String2));
+    else
+      TheCondState.CondMet = ExpectEqual == (String1 == String2);
+    TheCondState.Ignore = !TheCondState.CondMet;
+  }
+
+  return false;
+}
+
+/// parseDirectiveElse
+/// ::= else
+bool MasmParser::parseDirectiveElse(SMLoc DirectiveLoc) {
+  if (parseToken(AsmToken::EndOfStatement,
+                 "unexpected token in 'else' directive"))
+    return true;
+
+  if (TheCondState.TheCond != AsmCond::IfCond &&
+      TheCondState.TheCond != AsmCond::ElseIfCond)
+    return Error(DirectiveLoc, "Encountered an else that doesn't follow an if"
+                               " or an elseif");
+  TheCondState.TheCond = AsmCond::ElseCond;
+  bool LastIgnoreState = false;
+  if (!TheCondStack.empty())
+    LastIgnoreState = TheCondStack.back().Ignore;
+  if (LastIgnoreState || TheCondState.CondMet)
+    TheCondState.Ignore = true;
+  else
+    TheCondState.Ignore = false;
+
+  return false;
+}
+
+/// parseDirectiveEnd
+/// ::= end
+bool MasmParser::parseDirectiveEnd(SMLoc DirectiveLoc) {
+  if (parseToken(AsmToken::EndOfStatement,
+                 "unexpected token in 'end' directive"))
+    return true;
+
+  while (Lexer.isNot(AsmToken::Eof))
+    Lexer.Lex();
+
+  return false;
+}
+
+/// parseDirectiveError
+///   ::= .err [message]
+bool MasmParser::parseDirectiveError(SMLoc DirectiveLoc) {
+  if (!TheCondStack.empty()) {
+    if (TheCondStack.back().Ignore) {
+      eatToEndOfStatement();
+      return false;
+    }
+  }
+
+  StringRef Message = ".err directive invoked in source file";
+  if (Lexer.isNot(AsmToken::EndOfStatement))
+    Message = parseStringToEndOfStatement();
+  Lex();
+
+  return Error(DirectiveLoc, Message);
+}
+
+/// parseDirectiveErrorIfb
+///   ::= .errb textitem[, message]
+bool MasmParser::parseDirectiveErrorIfb(SMLoc DirectiveLoc, bool ExpectBlank) {
+  if (!TheCondStack.empty()) {
+    if (TheCondStack.back().Ignore) {
+      eatToEndOfStatement();
+      return false;
+    }
+  }
+
+  std::string Text;
+  if (parseTextItem(Text))
+    return Error(getTok().getLoc(), "missing text item in '.errb' directive");
+
+  StringRef Message = ".errb directive invoked in source file";
+  if (Lexer.isNot(AsmToken::EndOfStatement)) {
+    if (parseToken(AsmToken::Comma))
+      return addErrorSuffix(" in '.errb' directive");
+    Message = parseStringToEndOfStatement();
+  }
+  Lex();
+
+  if (Text.empty() == ExpectBlank)
+    return Error(DirectiveLoc, Message);
+  return false;
+}
+
+/// parseDirectiveErrorIfdef
+///   ::= .errdef name[, message]
+bool MasmParser::parseDirectiveErrorIfdef(SMLoc DirectiveLoc,
+                                          bool ExpectDefined) {
+  if (!TheCondStack.empty()) {
+    if (TheCondStack.back().Ignore) {
+      eatToEndOfStatement();
+      return false;
+    }
+  }
+
+  bool IsDefined = false;
+  unsigned RegNo;
+  SMLoc StartLoc, EndLoc;
+  IsDefined = (getTargetParser().tryParseRegister(RegNo, StartLoc, EndLoc) ==
+               MatchOperand_Success);
+  if (!IsDefined) {
+    StringRef Name;
+    if (check(parseIdentifier(Name), "expected identifier after '.errdef'"))
+      return true;
+
+    if (Variables.find(Name) != Variables.end()) {
+      IsDefined = true;
+    } else {
+      MCSymbol *Sym = getContext().lookupSymbol(Name);
+      IsDefined = (Sym && !Sym->isUndefined(false));
+    }
+  }
+
+  StringRef Message = ".errdef directive invoked in source file";
+  if (Lexer.isNot(AsmToken::EndOfStatement)) {
+    if (parseToken(AsmToken::Comma))
+      return addErrorSuffix(" in '.errdef' directive");
+    Message = parseStringToEndOfStatement();
+  }
+  Lex();
+
+  if (IsDefined == ExpectDefined)
+    return Error(DirectiveLoc, Message);
+  return false;
+}
+
+/// parseDirectiveErrorIfidn
+///   ::= .erridn textitem1, textitem2[, message]
+bool MasmParser::parseDirectiveErrorIfidn(SMLoc DirectiveLoc, bool ExpectEqual,
+                                          bool CaseInsensitive) {
+  if (!TheCondStack.empty()) {
+    if (TheCondStack.back().Ignore) {
+      eatToEndOfStatement();
+      return false;
+    }
+  }
+
+  std::string String1, String2;
+
+  if (parseTextItem(String1)) {
+    if (ExpectEqual)
+      return TokError("expected string parameter for '.erridn' directive");
+    return TokError("expected string parameter for '.errdif' directive");
+  }
+
+  if (Lexer.isNot(AsmToken::Comma)) {
+    if (ExpectEqual)
+      return TokError(
+          "expected comma after first string for '.erridn' directive");
+    return TokError(
+        "expected comma after first string for '.errdif' directive");
+  }
+  Lex();
+
+  if (parseTextItem(String2)) {
+    if (ExpectEqual)
+      return TokError("expected string parameter for '.erridn' directive");
+    return TokError("expected string parameter for '.errdif' directive");
+  }
+
+  StringRef Message;
+  if (ExpectEqual)
+    Message = ".erridn directive invoked in source file";
+  else
+    Message = ".errdif directive invoked in source file";
+  if (Lexer.isNot(AsmToken::EndOfStatement)) {
+    if (parseToken(AsmToken::Comma))
+      return addErrorSuffix(" in '.erridn' directive");
+    Message = parseStringToEndOfStatement();
+  }
+  Lex();
+
+  if (CaseInsensitive)
+    TheCondState.CondMet =
+        ExpectEqual == (StringRef(String1).equals_lower(String2));
+  else
+    TheCondState.CondMet = ExpectEqual == (String1 == String2);
+  TheCondState.Ignore = !TheCondState.CondMet;
+
+  if ((CaseInsensitive &&
+       ExpectEqual == StringRef(String1).equals_lower(String2)) ||
+      (ExpectEqual == (String1 == String2)))
+    return Error(DirectiveLoc, Message);
+  return false;
+}
+
+/// parseDirectiveErrorIfe
+///   ::= .erre expression[, message]
+bool MasmParser::parseDirectiveErrorIfe(SMLoc DirectiveLoc, bool ExpectZero) {
+  if (!TheCondStack.empty()) {
+    if (TheCondStack.back().Ignore) {
+      eatToEndOfStatement();
+      return false;
+    }
+  }
+
+  int64_t ExprValue;
+  if (parseAbsoluteExpression(ExprValue))
+    return addErrorSuffix(" in '.erre' directive");
+
+  StringRef Message = ".erre directive invoked in source file";
+  if (Lexer.isNot(AsmToken::EndOfStatement)) {
+    if (parseToken(AsmToken::Comma))
+      return addErrorSuffix(" in '.erre' directive");
+    Message = parseStringToEndOfStatement();
+  }
+  Lex();
+
+  if ((ExprValue == 0) == ExpectZero)
+    return Error(DirectiveLoc, Message);
+  return false;
+}
+
+/// parseDirectiveEndIf
+/// ::= .endif
+bool MasmParser::parseDirectiveEndIf(SMLoc DirectiveLoc) {
+  if (parseToken(AsmToken::EndOfStatement,
+                 "unexpected token in '.endif' directive"))
+    return true;
+
+  if ((TheCondState.TheCond == AsmCond::NoCond) || TheCondStack.empty())
+    return Error(DirectiveLoc, "Encountered a .endif that doesn't follow "
+                               "an .if or .else");
+  if (!TheCondStack.empty()) {
+    TheCondState = TheCondStack.back();
+    TheCondStack.pop_back();
+  }
+
+  return false;
+}
+
+void MasmParser::initializeDirectiveKindMap() {
+  DirectiveKindMap["="] = DK_ASSIGN;
+  DirectiveKindMap["equ"] = DK_EQU;
+  DirectiveKindMap["textequ"] = DK_TEXTEQU;
+  // DirectiveKindMap[".ascii"] = DK_ASCII;
+  // DirectiveKindMap[".asciz"] = DK_ASCIZ;
+  // DirectiveKindMap[".string"] = DK_STRING;
+  DirectiveKindMap["byte"] = DK_BYTE;
+  DirectiveKindMap["sbyte"] = DK_SBYTE;
+  DirectiveKindMap["word"] = DK_WORD;
+  DirectiveKindMap["sword"] = DK_SWORD;
+  DirectiveKindMap["dword"] = DK_DWORD;
+  DirectiveKindMap["sdword"] = DK_SDWORD;
+  DirectiveKindMap["fword"] = DK_FWORD;
+  DirectiveKindMap["qword"] = DK_QWORD;
+  DirectiveKindMap["sqword"] = DK_SQWORD;
+  DirectiveKindMap["real4"] = DK_REAL4;
+  DirectiveKindMap["real8"] = DK_REAL8;
+  DirectiveKindMap["align"] = DK_ALIGN;
+  // DirectiveKindMap[".org"] = DK_ORG;
+  DirectiveKindMap["extern"] = DK_EXTERN;
+  DirectiveKindMap["public"] = DK_PUBLIC;
+  // DirectiveKindMap[".comm"] = DK_COMM;
+  DirectiveKindMap["comment"] = DK_COMMENT;
+  DirectiveKindMap["include"] = DK_INCLUDE;
+  // DirectiveKindMap[".rept"] = DK_REPT;
+  // DirectiveKindMap[".rep"] = DK_REPT;
+  // DirectiveKindMap[".irp"] = DK_IRP;
+  // DirectiveKindMap[".irpc"] = DK_IRPC;
+  // DirectiveKindMap[".endr"] = DK_ENDR;
+  DirectiveKindMap["if"] = DK_IF;
+  DirectiveKindMap["ife"] = DK_IFE;
+  DirectiveKindMap["ifb"] = DK_IFB;
+  DirectiveKindMap["ifnb"] = DK_IFNB;
+  DirectiveKindMap["ifdef"] = DK_IFDEF;
+  DirectiveKindMap["ifndef"] = DK_IFNDEF;
+  DirectiveKindMap["ifdif"] = DK_IFDIF;
+  DirectiveKindMap["ifdifi"] = DK_IFDIFI;
+  DirectiveKindMap["ifidn"] = DK_IFIDN;
+  DirectiveKindMap["ifidni"] = DK_IFIDNI;
+  DirectiveKindMap["elseif"] = DK_ELSEIF;
+  DirectiveKindMap["elseifdef"] = DK_ELSEIFDEF;
+  DirectiveKindMap["elseifndef"] = DK_ELSEIFNDEF;
+  DirectiveKindMap["elseifdif"] = DK_ELSEIFDIF;
+  DirectiveKindMap["elseifidn"] = DK_ELSEIFIDN;
+  DirectiveKindMap["else"] = DK_ELSE;
+  DirectiveKindMap["end"] = DK_END;
+  DirectiveKindMap["endif"] = DK_ENDIF;
+  // DirectiveKindMap[".file"] = DK_FILE;
+  // DirectiveKindMap[".line"] = DK_LINE;
+  // DirectiveKindMap[".loc"] = DK_LOC;
+  // DirectiveKindMap[".stabs"] = DK_STABS;
+  // DirectiveKindMap[".cv_file"] = DK_CV_FILE;
+  // DirectiveKindMap[".cv_func_id"] = DK_CV_FUNC_ID;
+  // DirectiveKindMap[".cv_loc"] = DK_CV_LOC;
+  // DirectiveKindMap[".cv_linetable"] = DK_CV_LINETABLE;
+  // DirectiveKindMap[".cv_inline_linetable"] = DK_CV_INLINE_LINETABLE;
+  // DirectiveKindMap[".cv_inline_site_id"] = DK_CV_INLINE_SITE_ID;
+  // DirectiveKindMap[".cv_def_range"] = DK_CV_DEF_RANGE;
+  // DirectiveKindMap[".cv_string"] = DK_CV_STRING;
+  // DirectiveKindMap[".cv_stringtable"] = DK_CV_STRINGTABLE;
+  // DirectiveKindMap[".cv_filechecksums"] = DK_CV_FILECHECKSUMS;
+  // DirectiveKindMap[".cv_filechecksumoffset"] = DK_CV_FILECHECKSUM_OFFSET;
+  // DirectiveKindMap[".cv_fpo_data"] = DK_CV_FPO_DATA;
+  // DirectiveKindMap[".cfi_sections"] = DK_CFI_SECTIONS;
+  // DirectiveKindMap[".cfi_startproc"] = DK_CFI_STARTPROC;
+  // DirectiveKindMap[".cfi_endproc"] = DK_CFI_ENDPROC;
+  // DirectiveKindMap[".cfi_def_cfa"] = DK_CFI_DEF_CFA;
+  // DirectiveKindMap[".cfi_def_cfa_offset"] = DK_CFI_DEF_CFA_OFFSET;
+  // DirectiveKindMap[".cfi_adjust_cfa_offset"] = DK_CFI_ADJUST_CFA_OFFSET;
+  // DirectiveKindMap[".cfi_def_cfa_register"] = DK_CFI_DEF_CFA_REGISTER;
+  // DirectiveKindMap[".cfi_offset"] = DK_CFI_OFFSET;
+  // DirectiveKindMap[".cfi_rel_offset"] = DK_CFI_REL_OFFSET;
+  // DirectiveKindMap[".cfi_personality"] = DK_CFI_PERSONALITY;
+  // DirectiveKindMap[".cfi_lsda"] = DK_CFI_LSDA;
+  // DirectiveKindMap[".cfi_remember_state"] = DK_CFI_REMEMBER_STATE;
+  // DirectiveKindMap[".cfi_restore_state"] = DK_CFI_RESTORE_STATE;
+  // DirectiveKindMap[".cfi_same_value"] = DK_CFI_SAME_VALUE;
+  // DirectiveKindMap[".cfi_restore"] = DK_CFI_RESTORE;
+  // DirectiveKindMap[".cfi_escape"] = DK_CFI_ESCAPE;
+  // DirectiveKindMap[".cfi_return_column"] = DK_CFI_RETURN_COLUMN;
+  // DirectiveKindMap[".cfi_signal_frame"] = DK_CFI_SIGNAL_FRAME;
+  // DirectiveKindMap[".cfi_undefined"] = DK_CFI_UNDEFINED;
+  // DirectiveKindMap[".cfi_register"] = DK_CFI_REGISTER;
+  // DirectiveKindMap[".cfi_window_save"] = DK_CFI_WINDOW_SAVE;
+  // DirectiveKindMap[".cfi_b_key_frame"] = DK_CFI_B_KEY_FRAME;
+  // DirectiveKindMap[".macro"] = DK_MACRO;
+  // DirectiveKindMap[".exitm"] = DK_EXITM;
+  // DirectiveKindMap[".endm"] = DK_ENDM;
+  // DirectiveKindMap[".purgem"] = DK_PURGEM;
+  DirectiveKindMap[".err"] = DK_ERR;
+  DirectiveKindMap[".errb"] = DK_ERRB;
+  DirectiveKindMap[".errnb"] = DK_ERRNB;
+  DirectiveKindMap[".errdef"] = DK_ERRDEF;
+  DirectiveKindMap[".errndef"] = DK_ERRNDEF;
+  DirectiveKindMap[".errdif"] = DK_ERRDIF;
+  DirectiveKindMap[".errdifi"] = DK_ERRDIFI;
+  DirectiveKindMap[".erridn"] = DK_ERRIDN;
+  DirectiveKindMap[".erridni"] = DK_ERRIDNI;
+  DirectiveKindMap[".erre"] = DK_ERRE;
+  DirectiveKindMap[".errnz"] = DK_ERRNZ;
+  // DirectiveKindMap[".altmacro"] = DK_ALTMACRO;
+  // DirectiveKindMap[".noaltmacro"] = DK_NOALTMACRO;
+  DirectiveKindMap["db"] = DK_DB;
+  DirectiveKindMap["dd"] = DK_DD;
+  DirectiveKindMap["dq"] = DK_DQ;
+  DirectiveKindMap["dw"] = DK_DW;
+  DirectiveKindMap["echo"] = DK_ECHO;
+}
+
+MCAsmMacro *MasmParser::parseMacroLikeBody(SMLoc DirectiveLoc) {
+  AsmToken EndToken, StartToken = getTok();
+
+  unsigned NestLevel = 0;
+  while (true) {
+    // Check whether we have reached the end of the file.
+    if (getLexer().is(AsmToken::Eof)) {
+      printError(DirectiveLoc, "no matching '.endr' in definition");
+      return nullptr;
+    }
+
+    if (Lexer.is(AsmToken::Identifier) &&
+        (getTok().getIdentifier() == ".rep" ||
+         getTok().getIdentifier() == ".rept" ||
+         getTok().getIdentifier() == ".irp" ||
+         getTok().getIdentifier() == ".irpc")) {
+      ++NestLevel;
+    }
+
+    // Otherwise, check whether we have reached the .endr.
+    if (Lexer.is(AsmToken::Identifier) && getTok().getIdentifier() == ".endr") {
+      if (NestLevel == 0) {
+        EndToken = getTok();
+        Lex();
+        if (Lexer.isNot(AsmToken::EndOfStatement)) {
+          printError(getTok().getLoc(),
+                     "unexpected token in '.endr' directive");
+          return nullptr;
+        }
+        break;
+      }
+      --NestLevel;
+    }
+
+    // Otherwise, scan till the end of the statement.
+    eatToEndOfStatement();
+  }
+
+  const char *BodyStart = StartToken.getLoc().getPointer();
+  const char *BodyEnd = EndToken.getLoc().getPointer();
+  StringRef Body = StringRef(BodyStart, BodyEnd - BodyStart);
+
+  // We Are Anonymous.
+  MacroLikeBodies.emplace_back(StringRef(), Body, MCAsmMacroParameters());
+  return &MacroLikeBodies.back();
+}
+
+void MasmParser::instantiateMacroLikeBody(MCAsmMacro *M, SMLoc DirectiveLoc,
+                                          raw_svector_ostream &OS) {
+  OS << ".endr\n";
+
+  std::unique_ptr<MemoryBuffer> Instantiation =
+      MemoryBuffer::getMemBufferCopy(OS.str(), "<instantiation>");
+
+  // Create the macro instantiation object and add to the current macro
+  // instantiation stack.
+  MacroInstantiation *MI = new MacroInstantiation{
+      DirectiveLoc, CurBuffer, getTok().getLoc(), TheCondStack.size()};
+  ActiveMacros.push_back(MI);
+
+  // Jump to the macro instantiation and prime the lexer.
+  CurBuffer = SrcMgr.AddNewSourceBuffer(std::move(Instantiation), SMLoc());
+  Lexer.setBuffer(SrcMgr.getMemoryBuffer(CurBuffer)->getBuffer());
+  Lex();
+}
+
+/// parseDirectiveRept
+///   ::= .rep | .rept count
+bool MasmParser::parseDirectiveRept(SMLoc DirectiveLoc, StringRef Dir) {
+  const MCExpr *CountExpr;
+  SMLoc CountLoc = getTok().getLoc();
+  if (parseExpression(CountExpr))
+    return true;
+
+  int64_t Count;
+  if (!CountExpr->evaluateAsAbsolute(Count, getStreamer().getAssemblerPtr())) {
+    return Error(CountLoc, "unexpected token in '" + Dir + "' directive");
+  }
+
+  if (check(Count < 0, CountLoc, "Count is negative") ||
+      parseToken(AsmToken::EndOfStatement,
+                 "unexpected token in '" + Dir + "' directive"))
+    return true;
+
+  // Lex the rept definition.
+  MCAsmMacro *M = parseMacroLikeBody(DirectiveLoc);
+  if (!M)
+    return true;
+
+  // Macro instantiation is lexical, unfortunately. We construct a new buffer
+  // to hold the macro body with substitutions.
+  SmallString<256> Buf;
+  raw_svector_ostream OS(Buf);
+  while (Count--) {
+    // Note that the AtPseudoVariable is disabled for instantiations of .rep(t).
+    if (expandMacro(OS, M->Body, None, None, false, getTok().getLoc()))
+      return true;
+  }
+  instantiateMacroLikeBody(M, DirectiveLoc, OS);
+
+  return false;
+}
+
+/// parseDirectiveIrp
+/// ::= .irp symbol,values
+bool MasmParser::parseDirectiveIrp(SMLoc DirectiveLoc) {
+  MCAsmMacroParameter Parameter;
+  MCAsmMacroArguments A;
+  if (check(parseIdentifier(Parameter.Name),
+            "expected identifier in '.irp' directive") ||
+      parseToken(AsmToken::Comma, "expected comma in '.irp' directive") ||
+      parseMacroArguments(nullptr, A) ||
+      parseToken(AsmToken::EndOfStatement, "expected End of Statement"))
+    return true;
+
+  // Lex the irp definition.
+  MCAsmMacro *M = parseMacroLikeBody(DirectiveLoc);
+  if (!M)
+    return true;
+
+  // Macro instantiation is lexical, unfortunately. We construct a new buffer
+  // to hold the macro body with substitutions.
+  SmallString<256> Buf;
+  raw_svector_ostream OS(Buf);
+
+  for (const MCAsmMacroArgument &Arg : A) {
+    // Note that the AtPseudoVariable is enabled for instantiations of .irp.
+    // This is undocumented, but GAS seems to support it.
+    if (expandMacro(OS, M->Body, Parameter, Arg, true, getTok().getLoc()))
+      return true;
+  }
+
+  instantiateMacroLikeBody(M, DirectiveLoc, OS);
+
+  return false;
+}
+
+/// parseDirectiveIrpc
+/// ::= .irpc symbol,values
+bool MasmParser::parseDirectiveIrpc(SMLoc DirectiveLoc) {
+  MCAsmMacroParameter Parameter;
+  MCAsmMacroArguments A;
+
+  if (check(parseIdentifier(Parameter.Name),
+            "expected identifier in '.irpc' directive") ||
+      parseToken(AsmToken::Comma, "expected comma in '.irpc' directive") ||
+      parseMacroArguments(nullptr, A))
+    return true;
+
+  if (A.size() != 1 || A.front().size() != 1)
+    return TokError("unexpected token in '.irpc' directive");
+
+  // Eat the end of statement.
+  if (parseToken(AsmToken::EndOfStatement, "expected end of statement"))
+    return true;
+
+  // Lex the irpc definition.
+  MCAsmMacro *M = parseMacroLikeBody(DirectiveLoc);
+  if (!M)
+    return true;
+
+  // Macro instantiation is lexical, unfortunately. We construct a new buffer
+  // to hold the macro body with substitutions.
+  SmallString<256> Buf;
+  raw_svector_ostream OS(Buf);
+
+  StringRef Values = A.front().front().getString();
+  for (std::size_t I = 0, End = Values.size(); I != End; ++I) {
+    MCAsmMacroArgument Arg;
+    Arg.emplace_back(AsmToken::Identifier, Values.slice(I, I + 1));
+
+    // Note that the AtPseudoVariable is enabled for instantiations of .irpc.
+    // This is undocumented, but GAS seems to support it.
+    if (expandMacro(OS, M->Body, Parameter, Arg, true, getTok().getLoc()))
+      return true;
+  }
+
+  instantiateMacroLikeBody(M, DirectiveLoc, OS);
+
+  return false;
+}
+
+bool MasmParser::parseDirectiveEndr(SMLoc DirectiveLoc) {
+  if (ActiveMacros.empty())
+    return TokError("unmatched '.endr' directive");
+
+  // The only .repl that should get here are the ones created by
+  // instantiateMacroLikeBody.
+  assert(getLexer().is(AsmToken::EndOfStatement));
+
+  handleMacroExit();
+  return false;
+}
+
+bool MasmParser::parseDirectiveMSEmit(SMLoc IDLoc, ParseStatementInfo &Info,
+                                      size_t Len) {
+  const MCExpr *Value;
+  SMLoc ExprLoc = getLexer().getLoc();
+  if (parseExpression(Value))
+    return true;
+  const MCConstantExpr *MCE = dyn_cast<MCConstantExpr>(Value);
+  if (!MCE)
+    return Error(ExprLoc, "unexpected expression in _emit");
+  uint64_t IntValue = MCE->getValue();
+  if (!isUInt<8>(IntValue) && !isInt<8>(IntValue))
+    return Error(ExprLoc, "literal value out of range for directive");
+
+  Info.AsmRewrites->emplace_back(AOK_Emit, IDLoc, Len);
+  return false;
+}
+
+bool MasmParser::parseDirectiveMSAlign(SMLoc IDLoc, ParseStatementInfo &Info) {
+  const MCExpr *Value;
+  SMLoc ExprLoc = getLexer().getLoc();
+  if (parseExpression(Value))
+    return true;
+  const MCConstantExpr *MCE = dyn_cast<MCConstantExpr>(Value);
+  if (!MCE)
+    return Error(ExprLoc, "unexpected expression in align");
+  uint64_t IntValue = MCE->getValue();
+  if (!isPowerOf2_64(IntValue))
+    return Error(ExprLoc, "literal value not a power of two greater then zero");
+
+  Info.AsmRewrites->emplace_back(AOK_Align, IDLoc, 5, Log2_64(IntValue));
+  return false;
+}
+
+bool MasmParser::parseDirectiveEcho() {
+  StringRef Message = parseStringToEndOfStatement();
+  Lex();  // eat end of statement
+  llvm::outs() << Message << '\n';
+  return false;
+}
+
+// We are comparing pointers, but the pointers are relative to a single string.
+// Thus, this should always be deterministic.
+static int rewritesSort(const AsmRewrite *AsmRewriteA,
+                        const AsmRewrite *AsmRewriteB) {
+  if (AsmRewriteA->Loc.getPointer() < AsmRewriteB->Loc.getPointer())
+    return -1;
+  if (AsmRewriteB->Loc.getPointer() < AsmRewriteA->Loc.getPointer())
+    return 1;
+
+  // It's possible to have a SizeDirective, Imm/ImmPrefix and an Input/Output
+  // rewrite to the same location.  Make sure the SizeDirective rewrite is
+  // performed first, then the Imm/ImmPrefix and finally the Input/Output.  This
+  // ensures the sort algorithm is stable.
+  if (AsmRewritePrecedence[AsmRewriteA->Kind] >
+      AsmRewritePrecedence[AsmRewriteB->Kind])
+    return -1;
+
+  if (AsmRewritePrecedence[AsmRewriteA->Kind] <
+      AsmRewritePrecedence[AsmRewriteB->Kind])
+    return 1;
+  llvm_unreachable("Unstable rewrite sort.");
+}
+
+bool MasmParser::parseMSInlineAsm(
+    void *AsmLoc, std::string &AsmString, unsigned &NumOutputs,
+    unsigned &NumInputs, SmallVectorImpl<std::pair<void *, bool>> &OpDecls,
+    SmallVectorImpl<std::string> &Constraints,
+    SmallVectorImpl<std::string> &Clobbers, const MCInstrInfo *MII,
+    const MCInstPrinter *IP, MCAsmParserSemaCallback &SI) {
+  SmallVector<void *, 4> InputDecls;
+  SmallVector<void *, 4> OutputDecls;
+  SmallVector<bool, 4> InputDeclsAddressOf;
+  SmallVector<bool, 4> OutputDeclsAddressOf;
+  SmallVector<std::string, 4> InputConstraints;
+  SmallVector<std::string, 4> OutputConstraints;
+  SmallVector<unsigned, 4> ClobberRegs;
+
+  SmallVector<AsmRewrite, 4> AsmStrRewrites;
+
+  // Prime the lexer.
+  Lex();
+
+  // While we have input, parse each statement.
+  unsigned InputIdx = 0;
+  unsigned OutputIdx = 0;
+  while (getLexer().isNot(AsmToken::Eof)) {
+    // Parse curly braces marking block start/end
+    if (parseCurlyBlockScope(AsmStrRewrites))
+      continue;
+
+    ParseStatementInfo Info(&AsmStrRewrites);
+    bool StatementErr = parseStatement(Info, &SI);
+
+    if (StatementErr || Info.ParseError) {
+      // Emit pending errors if any exist.
+      printPendingErrors();
+      return true;
+    }
+
+    // No pending error should exist here.
+    assert(!hasPendingError() && "unexpected error from parseStatement");
+
+    if (Info.Opcode == ~0U)
+      continue;
+
+    const MCInstrDesc &Desc = MII->get(Info.Opcode);
+
+    // Build the list of clobbers, outputs and inputs.
+    for (unsigned i = 1, e = Info.ParsedOperands.size(); i != e; ++i) {
+      MCParsedAsmOperand &Operand = *Info.ParsedOperands[i];
+
+      // Register operand.
+      if (Operand.isReg() && !Operand.needAddressOf() &&
+          !getTargetParser().OmitRegisterFromClobberLists(Operand.getReg())) {
+        unsigned NumDefs = Desc.getNumDefs();
+        // Clobber.
+        if (NumDefs && Operand.getMCOperandNum() < NumDefs)
+          ClobberRegs.push_back(Operand.getReg());
+        continue;
+      }
+
+      // Expr/Input or Output.
+      StringRef SymName = Operand.getSymName();
+      if (SymName.empty())
+        continue;
+
+      void *OpDecl = Operand.getOpDecl();
+      if (!OpDecl)
+        continue;
+
+      StringRef Constraint = Operand.getConstraint();
+      if (Operand.isImm()) {
+        // Offset as immediate
+        if (Operand.isOffsetOfLocal())
+          Constraint = "r";
+        else
+          Constraint = "i";
+      }
+
+      bool isOutput = (i == 1) && Desc.mayStore();
+      SMLoc Start = SMLoc::getFromPointer(SymName.data());
+      if (isOutput) {
+        ++InputIdx;
+        OutputDecls.push_back(OpDecl);
+        OutputDeclsAddressOf.push_back(Operand.needAddressOf());
+        OutputConstraints.push_back(("=" + Constraint).str());
+        AsmStrRewrites.emplace_back(AOK_Output, Start, SymName.size());
+      } else {
+        InputDecls.push_back(OpDecl);
+        InputDeclsAddressOf.push_back(Operand.needAddressOf());
+        InputConstraints.push_back(Constraint.str());
+        if (Desc.OpInfo[i - 1].isBranchTarget())
+          AsmStrRewrites.emplace_back(AOK_CallInput, Start, SymName.size());
+        else
+          AsmStrRewrites.emplace_back(AOK_Input, Start, SymName.size());
+      }
+    }
+
+    // Consider implicit defs to be clobbers.  Think of cpuid and push.
+    ArrayRef<MCPhysReg> ImpDefs(Desc.getImplicitDefs(),
+                                Desc.getNumImplicitDefs());
+    ClobberRegs.insert(ClobberRegs.end(), ImpDefs.begin(), ImpDefs.end());
+  }
+
+  // Set the number of Outputs and Inputs.
+  NumOutputs = OutputDecls.size();
+  NumInputs = InputDecls.size();
+
+  // Set the unique clobbers.
+  array_pod_sort(ClobberRegs.begin(), ClobberRegs.end());
+  ClobberRegs.erase(std::unique(ClobberRegs.begin(), ClobberRegs.end()),
+                    ClobberRegs.end());
+  Clobbers.assign(ClobberRegs.size(), std::string());
+  for (unsigned I = 0, E = ClobberRegs.size(); I != E; ++I) {
+    raw_string_ostream OS(Clobbers[I]);
+    IP->printRegName(OS, ClobberRegs[I]);
+  }
+
+  // Merge the various outputs and inputs.  Output are expected first.
+  if (NumOutputs || NumInputs) {
+    unsigned NumExprs = NumOutputs + NumInputs;
+    OpDecls.resize(NumExprs);
+    Constraints.resize(NumExprs);
+    for (unsigned i = 0; i < NumOutputs; ++i) {
+      OpDecls[i] = std::make_pair(OutputDecls[i], OutputDeclsAddressOf[i]);
+      Constraints[i] = OutputConstraints[i];
+    }
+    for (unsigned i = 0, j = NumOutputs; i < NumInputs; ++i, ++j) {
+      OpDecls[j] = std::make_pair(InputDecls[i], InputDeclsAddressOf[i]);
+      Constraints[j] = InputConstraints[i];
+    }
+  }
+
+  // Build the IR assembly string.
+  std::string AsmStringIR;
+  raw_string_ostream OS(AsmStringIR);
+  StringRef ASMString =
+      SrcMgr.getMemoryBuffer(SrcMgr.getMainFileID())->getBuffer();
+  const char *AsmStart = ASMString.begin();
+  const char *AsmEnd = ASMString.end();
+  array_pod_sort(AsmStrRewrites.begin(), AsmStrRewrites.end(), rewritesSort);
+  for (auto it = AsmStrRewrites.begin(); it != AsmStrRewrites.end(); ++it) {
+    const AsmRewrite &AR = *it;
+    // Check if this has already been covered by another rewrite...
+    if (AR.Done)
+      continue;
+    AsmRewriteKind Kind = AR.Kind;
+
+    const char *Loc = AR.Loc.getPointer();
+    assert(Loc >= AsmStart && "Expected Loc to be at or after Start!");
+
+    // Emit everything up to the immediate/expression.
+    if (unsigned Len = Loc - AsmStart)
+      OS << StringRef(AsmStart, Len);
+
+    // Skip the original expression.
+    if (Kind == AOK_Skip) {
+      AsmStart = Loc + AR.Len;
+      continue;
+    }
+
+    unsigned AdditionalSkip = 0;
+    // Rewrite expressions in $N notation.
+    switch (Kind) {
+    default:
+      break;
+    case AOK_IntelExpr:
+      assert(AR.IntelExp.isValid() && "cannot write invalid intel expression");
+      if (AR.IntelExp.NeedBracs)
+        OS << "[";
+      if (AR.IntelExp.hasBaseReg())
+        OS << AR.IntelExp.BaseReg;
+      if (AR.IntelExp.hasIndexReg())
+        OS << (AR.IntelExp.hasBaseReg() ? " + " : "")
+           << AR.IntelExp.IndexReg;
+      if (AR.IntelExp.Scale > 1)
+        OS << " * $$" << AR.IntelExp.Scale;
+      if (AR.IntelExp.hasOffset()) {
+        if (AR.IntelExp.hasRegs())
+          OS << " + ";
+        // Fuse this rewrite with a rewrite of the offset name, if present.
+        StringRef OffsetName = AR.IntelExp.OffsetName;
+        SMLoc OffsetLoc = SMLoc::getFromPointer(AR.IntelExp.OffsetName.data());
+        size_t OffsetLen = OffsetName.size();
+        auto rewrite_it = std::find_if(
+            it, AsmStrRewrites.end(), [&](const AsmRewrite &FusingAR) {
+              return FusingAR.Loc == OffsetLoc && FusingAR.Len == OffsetLen &&
+                     (FusingAR.Kind == AOK_Input ||
+                      FusingAR.Kind == AOK_CallInput);
+            });
+        if (rewrite_it == AsmStrRewrites.end()) {
+          OS << "offset " << OffsetName;
+        } else if (rewrite_it->Kind == AOK_CallInput) {
+          OS << "${" << InputIdx++ << ":P}";
+          rewrite_it->Done = true;
+        } else {
+          OS << '$' << InputIdx++;
+          rewrite_it->Done = true;
+        }
+      }
+      if (AR.IntelExp.Imm || AR.IntelExp.emitImm())
+        OS << (AR.IntelExp.emitImm() ? "$$" : " + $$") << AR.IntelExp.Imm;
+      if (AR.IntelExp.NeedBracs)
+        OS << "]";
+      break;
+    case AOK_Label:
+      OS << Ctx.getAsmInfo()->getPrivateLabelPrefix() << AR.Label;
+      break;
+    case AOK_Input:
+      OS << '$' << InputIdx++;
+      break;
+    case AOK_CallInput:
+      OS << "${" << InputIdx++ << ":P}";
+      break;
+    case AOK_Output:
+      OS << '$' << OutputIdx++;
+      break;
+    case AOK_SizeDirective:
+      switch (AR.Val) {
+      default: break;
+      case 8:  OS << "byte ptr "; break;
+      case 16: OS << "word ptr "; break;
+      case 32: OS << "dword ptr "; break;
+      case 64: OS << "qword ptr "; break;
+      case 80: OS << "xword ptr "; break;
+      case 128: OS << "xmmword ptr "; break;
+      case 256: OS << "ymmword ptr "; break;
+      }
+      break;
+    case AOK_Emit:
+      OS << ".byte";
+      break;
+    case AOK_Align: {
+      // MS alignment directives are measured in bytes. If the native assembler
+      // measures alignment in bytes, we can pass it straight through.
+      OS << ".align";
+      if (getContext().getAsmInfo()->getAlignmentIsInBytes())
+        break;
+
+      // Alignment is in log2 form, so print that instead and skip the original
+      // immediate.
+      unsigned Val = AR.Val;
+      OS << ' ' << Val;
+      assert(Val < 10 && "Expected alignment less then 2^10.");
+      AdditionalSkip = (Val < 4) ? 2 : Val < 7 ? 3 : 4;
+      break;
+    }
+    case AOK_EVEN:
+      OS << ".even";
+      break;
+    case AOK_EndOfStatement:
+      OS << "\n\t";
+      break;
+    }
+
+    // Skip the original expression.
+    AsmStart = Loc + AR.Len + AdditionalSkip;
+  }
+
+  // Emit the remainder of the asm string.
+  if (AsmStart != AsmEnd)
+    OS << StringRef(AsmStart, AsmEnd - AsmStart);
+
+  AsmString = OS.str();
+  return false;
+}
+
+/// Create an MCAsmParser instance.
+MCAsmParser *llvm::createMCMasmParser(SourceMgr &SM, MCContext &C,
+                                      MCStreamer &Out, const MCAsmInfo &MAI,
+                                      unsigned CB) {
+  return new MasmParser(SM, C, Out, MAI, CB);
+}

diff  --git a/llvm/lib/MC/MCTargetOptions.cpp b/llvm/lib/MC/MCTargetOptions.cpp
index 5848e3ecadbe..0a5d0cefeddc 100644
--- a/llvm/lib/MC/MCTargetOptions.cpp
+++ b/llvm/lib/MC/MCTargetOptions.cpp
@@ -21,3 +21,7 @@ MCTargetOptions::MCTargetOptions()
 StringRef MCTargetOptions::getABIName() const {
   return ABIName;
 }
+
+StringRef MCTargetOptions::getAssemblyLanguage() const {
+  return AssemblyLanguage;
+}

diff  --git a/llvm/lib/Target/X86/MCTargetDesc/X86MCAsmInfo.cpp b/llvm/lib/Target/X86/MCTargetDesc/X86MCAsmInfo.cpp
index d986c829d98e..1c697a1ad632 100644
--- a/llvm/lib/Target/X86/MCTargetDesc/X86MCAsmInfo.cpp
+++ b/llvm/lib/Target/X86/MCTargetDesc/X86MCAsmInfo.cpp
@@ -145,6 +145,16 @@ X86MCAsmInfoMicrosoft::X86MCAsmInfoMicrosoft(const Triple &Triple) {
   UseIntegratedAssembler = true;
 }
 
+void X86MCAsmInfoMicrosoftMASM::anchor() { }
+
+X86MCAsmInfoMicrosoftMASM::X86MCAsmInfoMicrosoftMASM(const Triple &Triple)
+    : X86MCAsmInfoMicrosoft(Triple) {
+  DollarIsPC = true;
+  SeparatorString = "\n";
+  CommentString = ";";
+  AllowSymbolAtNameStart = true;
+}
+
 void X86MCAsmInfoGNUCOFF::anchor() { }
 
 X86MCAsmInfoGNUCOFF::X86MCAsmInfoGNUCOFF(const Triple &Triple) {

diff  --git a/llvm/lib/Target/X86/MCTargetDesc/X86MCAsmInfo.h b/llvm/lib/Target/X86/MCTargetDesc/X86MCAsmInfo.h
index b2369647a40f..5dfb89196e83 100644
--- a/llvm/lib/Target/X86/MCTargetDesc/X86MCAsmInfo.h
+++ b/llvm/lib/Target/X86/MCTargetDesc/X86MCAsmInfo.h
@@ -49,6 +49,13 @@ class X86MCAsmInfoMicrosoft : public MCAsmInfoMicrosoft {
   explicit X86MCAsmInfoMicrosoft(const Triple &Triple);
 };
 
+class X86MCAsmInfoMicrosoftMASM : public X86MCAsmInfoMicrosoft {
+  void anchor() override;
+
+public:
+  explicit X86MCAsmInfoMicrosoftMASM(const Triple &Triple);
+};
+
 class X86MCAsmInfoGNUCOFF : public MCAsmInfoGNUCOFF {
   void anchor() override;
 

diff  --git a/llvm/lib/Target/X86/MCTargetDesc/X86MCTargetDesc.cpp b/llvm/lib/Target/X86/MCTargetDesc/X86MCTargetDesc.cpp
index 5594f342bfa1..9406f18f7b76 100644
--- a/llvm/lib/Target/X86/MCTargetDesc/X86MCTargetDesc.cpp
+++ b/llvm/lib/Target/X86/MCTargetDesc/X86MCTargetDesc.cpp
@@ -335,7 +335,10 @@ static MCAsmInfo *createX86MCAsmInfo(const MCRegisterInfo &MRI,
     MAI = new X86ELFMCAsmInfo(TheTriple);
   } else if (TheTriple.isWindowsMSVCEnvironment() ||
              TheTriple.isWindowsCoreCLREnvironment()) {
-    MAI = new X86MCAsmInfoMicrosoft(TheTriple);
+    if (Options.getAssemblyLanguage().equals_lower("masm"))
+      MAI = new X86MCAsmInfoMicrosoftMASM(TheTriple);
+    else
+      MAI = new X86MCAsmInfoMicrosoft(TheTriple);
   } else if (TheTriple.isOSCygMing() ||
              TheTriple.isWindowsItaniumEnvironment()) {
     MAI = new X86MCAsmInfoGNUCOFF(TheTriple);

diff  --git a/llvm/test/tools/llvm-ml/basic.test b/llvm/test/tools/llvm-ml/basic.test
index 8e8967f5c9d2..30aa860f2b90 100644
--- a/llvm/test/tools/llvm-ml/basic.test
+++ b/llvm/test/tools/llvm-ml/basic.test
@@ -1,4 +1,3 @@
-# REQUIRES: x86-registered-target
 # RUN: not llvm-ml %t.blah -o /dev/null 2>&1 | FileCheck --check-prefix=ENOENT %s
 
 # ENOENT: {{.*}}.blah: {{[Nn]}}o such file or directory

diff  --git a/llvm/test/tools/llvm-ml/lit.local.cfg b/llvm/test/tools/llvm-ml/lit.local.cfg
new file mode 100644
index 000000000000..7230f35fdb83
--- /dev/null
+++ b/llvm/test/tools/llvm-ml/lit.local.cfg
@@ -0,0 +1,3 @@
+if not ('X86' in config.root.targets):
+    # We need support for X86.
+    config.unsupported = True

diff  --git a/llvm/tools/llvm-ml/llvm-ml.cpp b/llvm/tools/llvm-ml/llvm-ml.cpp
index 1b30f3e831e6..2e8ecd95f6b9 100644
--- a/llvm/tools/llvm-ml/llvm-ml.cpp
+++ b/llvm/tools/llvm-ml/llvm-ml.cpp
@@ -189,7 +189,8 @@ static int AssembleInput(const char *ProgName, const Target *TheTarget,
                          SourceMgr &SrcMgr, MCContext &Ctx, MCStreamer &Str,
                          MCAsmInfo &MAI, MCSubtargetInfo &STI,
                          MCInstrInfo &MCII, MCTargetOptions &MCOptions) {
-  std::unique_ptr<MCAsmParser> Parser(createMCAsmParser(SrcMgr, Ctx, Str, MAI));
+  std::unique_ptr<MCAsmParser> Parser(
+      createMCMasmParser(SrcMgr, Ctx, Str, MAI));
   std::unique_ptr<MCTargetAsmParser> TAP(
       TheTarget->createMCAsmParser(STI, *Parser, MCII, MCOptions));
 
@@ -222,6 +223,7 @@ int main(int argc, char **argv) {
 
   cl::ParseCommandLineOptions(argc, argv, "llvm machine code playground\n");
   MCTargetOptions MCOptions = InitMCTargetOptionsFromFlags();
+  MCOptions.AssemblyLanguage = "masm";
 
   const char *ProgName = argv[0];
   const Target *TheTarget = GetTarget(ProgName);

diff  --git a/llvm/utils/gn/secondary/llvm/lib/MC/MCParser/BUILD.gn b/llvm/utils/gn/secondary/llvm/lib/MC/MCParser/BUILD.gn
index 5c9d23074693..c3739c966c49 100644
--- a/llvm/utils/gn/secondary/llvm/lib/MC/MCParser/BUILD.gn
+++ b/llvm/utils/gn/secondary/llvm/lib/MC/MCParser/BUILD.gn
@@ -14,6 +14,7 @@ static_library("MCParser") {
     "MCAsmLexer.cpp",
     "MCAsmParser.cpp",
     "MCAsmParserExtension.cpp",
+    "MasmParser.cpp",
     "MCTargetAsmParser.cpp",
     "WasmAsmParser.cpp",
   ]


        


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