diff --git a/llvm/test/CMakeLists.txt b/llvm/test/CMakeLists.txt
--- a/llvm/test/CMakeLists.txt
+++ b/llvm/test/CMakeLists.txt
@@ -80,6 +80,7 @@
           llvm-lto2
           llvm-mc
           llvm-mca
+          llvm-ml
           llvm-modextract
           llvm-mt
           llvm-nm
diff --git a/llvm/test/tools/llvm-ml/basic.test b/llvm/test/tools/llvm-ml/basic.test
new file mode 100644
--- /dev/null
+++ b/llvm/test/tools/llvm-ml/basic.test
@@ -0,0 +1,3 @@
+# 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/run.test b/llvm/test/tools/llvm-ml/run.test
new file mode 100644
--- /dev/null
+++ b/llvm/test/tools/llvm-ml/run.test
@@ -0,0 +1,3 @@
+# RUN: llvm-ml --help | FileCheck %s
+
+# CHECK: USAGE: llvm-ml
\ No newline at end of file
diff --git a/llvm/tools/llvm-ml/CMakeLists.txt b/llvm/tools/llvm-ml/CMakeLists.txt
new file mode 100644
--- /dev/null
+++ b/llvm/tools/llvm-ml/CMakeLists.txt
@@ -0,0 +1,15 @@
+set(LLVM_LINK_COMPONENTS
+  AllTargetsAsmPrinters
+  AllTargetsAsmParsers
+  AllTargetsDescs
+  AllTargetsDisassemblers
+  AllTargetsInfos
+  MC
+  MCParser
+  Support
+  )
+
+add_llvm_tool(llvm-ml
+  llvm-ml.cpp
+  Disassembler.cpp
+  )
diff --git a/llvm/tools/llvm-ml/Disassembler.h b/llvm/tools/llvm-ml/Disassembler.h
new file mode 100644
--- /dev/null
+++ b/llvm/tools/llvm-ml/Disassembler.h
@@ -0,0 +1,41 @@
+//===- Disassembler.h - Text File Disassembler ----------------------------===//
+//
+// 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 disassembler of strings of bytes written in
+// hexadecimal, from standard input or from a file.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_TOOLS_LLVM_MC_DISASSEMBLER_H
+#define LLVM_TOOLS_LLVM_MC_DISASSEMBLER_H
+
+#include <string>
+
+namespace llvm {
+
+class MemoryBuffer;
+class Target;
+class raw_ostream;
+class SourceMgr;
+class MCSubtargetInfo;
+class MCStreamer;
+
+class Disassembler {
+public:
+  static int disassemble(const Target &T,
+                         const std::string &Triple,
+                         MCSubtargetInfo &STI,
+                         MCStreamer &Streamer,
+                         MemoryBuffer &Buffer,
+                         SourceMgr &SM,
+                         raw_ostream &Out);
+};
+
+} // namespace llvm
+
+#endif
diff --git a/llvm/tools/llvm-ml/Disassembler.cpp b/llvm/tools/llvm-ml/Disassembler.cpp
new file mode 100644
--- /dev/null
+++ b/llvm/tools/llvm-ml/Disassembler.cpp
@@ -0,0 +1,212 @@
+//===- Disassembler.cpp - Disassembler for hex strings --------------------===//
+//
+// 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 disassembler of strings of bytes written in
+// hexadecimal, from standard input or from a file.
+//
+//===----------------------------------------------------------------------===//
+
+#include "Disassembler.h"
+#include "llvm/ADT/Triple.h"
+#include "llvm/MC/MCAsmInfo.h"
+#include "llvm/MC/MCContext.h"
+#include "llvm/MC/MCDisassembler/MCDisassembler.h"
+#include "llvm/MC/MCInst.h"
+#include "llvm/MC/MCRegisterInfo.h"
+#include "llvm/MC/MCStreamer.h"
+#include "llvm/MC/MCSubtargetInfo.h"
+#include "llvm/Support/MemoryBuffer.h"
+#include "llvm/Support/SourceMgr.h"
+#include "llvm/Support/TargetRegistry.h"
+#include "llvm/Support/raw_ostream.h"
+
+using namespace llvm;
+
+typedef std::pair<std::vector<unsigned char>, std::vector<const char *>>
+    ByteArrayTy;
+
+static bool PrintInsts(const MCDisassembler &DisAsm,
+                       const ByteArrayTy &Bytes,
+                       SourceMgr &SM, raw_ostream &Out,
+                       MCStreamer &Streamer, bool InAtomicBlock,
+                       const MCSubtargetInfo &STI) {
+  ArrayRef<uint8_t> Data(Bytes.first.data(), Bytes.first.size());
+
+  // Disassemble it to strings.
+  uint64_t Size;
+  uint64_t Index;
+
+  for (Index = 0; Index < Bytes.first.size(); Index += Size) {
+    MCInst Inst;
+
+    MCDisassembler::DecodeStatus S;
+    S = DisAsm.getInstruction(Inst, Size, Data.slice(Index), Index,
+                              /*REMOVE*/ nulls(), nulls());
+    switch (S) {
+    case MCDisassembler::Fail:
+      SM.PrintMessage(SMLoc::getFromPointer(Bytes.second[Index]),
+                      SourceMgr::DK_Warning,
+                      "invalid instruction encoding");
+      // Don't try to resynchronise the stream in a block
+      if (InAtomicBlock)
+        return true;
+
+      if (Size == 0)
+        Size = 1;  // skip illegible bytes
+
+      break;
+
+    case MCDisassembler::SoftFail:
+      SM.PrintMessage(SMLoc::getFromPointer(Bytes.second[Index]),
+                      SourceMgr::DK_Warning,
+                      "potentially undefined instruction encoding");
+      LLVM_FALLTHROUGH;
+
+    case MCDisassembler::Success:
+      Streamer.EmitInstruction(Inst, STI);
+      break;
+    }
+  }
+
+  return false;
+}
+
+static bool SkipToToken(StringRef &Str) {
+  for (;;) {
+    if (Str.empty())
+      return false;
+
+    // Strip horizontal whitespace and commas.
+    if (size_t Pos = Str.find_first_not_of(" \t\r\n,")) {
+      Str = Str.substr(Pos);
+      continue;
+    }
+
+    // If this is the start of a comment, remove the rest of the line.
+    if (Str[0] == '#') {
+        Str = Str.substr(Str.find_first_of('\n'));
+      continue;
+    }
+    return true;
+  }
+}
+
+
+static bool ByteArrayFromString(ByteArrayTy &ByteArray,
+                                StringRef &Str,
+                                SourceMgr &SM) {
+  while (SkipToToken(Str)) {
+    // Handled by higher level
+    if (Str[0] == '[' || Str[0] == ']')
+      return false;
+
+    // Get the current token.
+    size_t Next = Str.find_first_of(" \t\n\r,#[]");
+    StringRef Value = Str.substr(0, Next);
+
+    // Convert to a byte and add to the byte vector.
+    unsigned ByteVal;
+    if (Value.getAsInteger(0, ByteVal) || ByteVal > 255) {
+      // If we have an error, print it and skip to the end of line.
+      SM.PrintMessage(SMLoc::getFromPointer(Value.data()), SourceMgr::DK_Error,
+                      "invalid input token");
+      Str = Str.substr(Str.find('\n'));
+      ByteArray.first.clear();
+      ByteArray.second.clear();
+      continue;
+    }
+
+    ByteArray.first.push_back(ByteVal);
+    ByteArray.second.push_back(Value.data());
+    Str = Str.substr(Next);
+  }
+
+  return false;
+}
+
+int Disassembler::disassemble(const Target &T,
+                              const std::string &Triple,
+                              MCSubtargetInfo &STI,
+                              MCStreamer &Streamer,
+                              MemoryBuffer &Buffer,
+                              SourceMgr &SM,
+                              raw_ostream &Out) {
+  std::unique_ptr<const MCRegisterInfo> MRI(T.createMCRegInfo(Triple));
+  if (!MRI) {
+    errs() << "error: no register info for target " << Triple << "\n";
+    return -1;
+  }
+
+  MCTargetOptions MCOptions;
+  std::unique_ptr<const MCAsmInfo> MAI(
+      T.createMCAsmInfo(*MRI, Triple, MCOptions));
+  if (!MAI) {
+    errs() << "error: no assembly info for target " << Triple << "\n";
+    return -1;
+  }
+
+  // Set up the MCContext for creating symbols and MCExpr's.
+  MCContext Ctx(MAI.get(), MRI.get(), nullptr);
+
+  std::unique_ptr<const MCDisassembler> DisAsm(
+    T.createMCDisassembler(STI, Ctx));
+  if (!DisAsm) {
+    errs() << "error: no disassembler for target " << Triple << "\n";
+    return -1;
+  }
+
+  // Set up initial section manually here
+  Streamer.InitSections(false);
+
+  bool ErrorOccurred = false;
+
+  // Convert the input to a vector for disassembly.
+  ByteArrayTy ByteArray;
+  StringRef Str = Buffer.getBuffer();
+  bool InAtomicBlock = false;
+
+  while (SkipToToken(Str)) {
+    ByteArray.first.clear();
+    ByteArray.second.clear();
+
+    if (Str[0] == '[') {
+      if (InAtomicBlock) {
+        SM.PrintMessage(SMLoc::getFromPointer(Str.data()), SourceMgr::DK_Error,
+                        "nested atomic blocks make no sense");
+        ErrorOccurred = true;
+      }
+      InAtomicBlock = true;
+      Str = Str.drop_front();
+      continue;
+    } else if (Str[0] == ']') {
+      if (!InAtomicBlock) {
+        SM.PrintMessage(SMLoc::getFromPointer(Str.data()), SourceMgr::DK_Error,
+                        "attempt to close atomic block without opening");
+        ErrorOccurred = true;
+      }
+      InAtomicBlock = false;
+      Str = Str.drop_front();
+      continue;
+    }
+
+    // It's a real token, get the bytes and emit them
+    ErrorOccurred |= ByteArrayFromString(ByteArray, Str, SM);
+
+    if (!ByteArray.first.empty())
+      ErrorOccurred |= PrintInsts(*DisAsm, ByteArray, SM, Out, Streamer,
+                                  InAtomicBlock, STI);
+  }
+
+  if (InAtomicBlock) {
+    SM.PrintMessage(SMLoc::getFromPointer(Str.data()), SourceMgr::DK_Error,
+                    "unclosed atomic block");
+    ErrorOccurred = true;
+  }
+
+  return ErrorOccurred;
+}
diff --git a/llvm/tools/llvm-ml/llvm-ml.cpp b/llvm/tools/llvm-ml/llvm-ml.cpp
new file mode 100644
--- /dev/null
+++ b/llvm/tools/llvm-ml/llvm-ml.cpp
@@ -0,0 +1,392 @@
+//===-- llvm-ml.cpp - masm-compatible assembler -----------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+// A simple driver around MasmParser; based on llvm-mc.
+//
+//===----------------------------------------------------------------------===//
+
+#include "Disassembler.h"
+
+#include "llvm/MC/MCAsmBackend.h"
+#include "llvm/MC/MCAsmInfo.h"
+#include "llvm/MC/MCCodeEmitter.h"
+#include "llvm/MC/MCContext.h"
+#include "llvm/MC/MCInstPrinter.h"
+#include "llvm/MC/MCInstrInfo.h"
+#include "llvm/MC/MCObjectFileInfo.h"
+#include "llvm/MC/MCObjectWriter.h"
+#include "llvm/MC/MCParser/AsmLexer.h"
+#include "llvm/MC/MCParser/MCTargetAsmParser.h"
+#include "llvm/MC/MCRegisterInfo.h"
+#include "llvm/MC/MCStreamer.h"
+#include "llvm/MC/MCSubtargetInfo.h"
+#include "llvm/MC/MCTargetOptionsCommandFlags.inc"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Support/Compression.h"
+#include "llvm/Support/FileUtilities.h"
+#include "llvm/Support/FormattedStream.h"
+#include "llvm/Support/Host.h"
+#include "llvm/Support/InitLLVM.h"
+#include "llvm/Support/MemoryBuffer.h"
+#include "llvm/Support/SourceMgr.h"
+#include "llvm/Support/TargetRegistry.h"
+#include "llvm/Support/TargetSelect.h"
+#include "llvm/Support/ToolOutputFile.h"
+#include "llvm/Support/WithColor.h"
+
+using namespace llvm;
+
+static cl::opt<std::string>
+InputFilename(cl::Positional, cl::desc("<input file>"), cl::init("-"));
+
+static cl::opt<std::string> OutputFilename("o", cl::desc("Output filename"),
+                                           cl::value_desc("filename"),
+                                           cl::init("-"));
+
+static cl::opt<bool>
+ShowEncoding("show-encoding", cl::desc("Show instruction encodings"));
+
+static cl::opt<bool>
+ShowInst("show-inst", cl::desc("Show internal instruction representation"));
+
+static cl::opt<bool>
+ShowInstOperands("show-inst-operands",
+                 cl::desc("Show instructions operands as parsed"));
+
+static cl::opt<bool>
+OutputATTAsm("output-att-asm", cl::desc("Use ATT syntax for output printing"));
+
+static cl::opt<bool>
+PrintImmHex("print-imm-hex", cl::init(false),
+            cl::desc("Prefer hex format for immediate values"));
+
+static cl::opt<bool>
+    PreserveComments("preserve-comments",
+                     cl::desc("Preserve Comments in outputted assembly"));
+
+enum OutputFileType {
+  OFT_Null,
+  OFT_AssemblyFile,
+  OFT_ObjectFile
+};
+static cl::opt<OutputFileType>
+FileType("filetype", cl::init(OFT_ObjectFile),
+  cl::desc("Choose an output file type:"),
+  cl::values(
+       clEnumValN(OFT_AssemblyFile, "asm",
+                  "Emit an assembly ('.s') file"),
+       clEnumValN(OFT_Null, "null",
+                  "Don't emit anything (for timing purposes)"),
+       clEnumValN(OFT_ObjectFile, "obj",
+                  "Emit a native object ('.o') file")));
+
+static cl::list<std::string>
+IncludeDirs("I", cl::desc("Directory of include files"),
+            cl::value_desc("directory"), cl::Prefix);
+
+enum BitnessType {
+  m32, m64,
+};
+cl::opt<BitnessType> Bitness(cl::desc("Choose bitness:"), cl::init(m64),
+                              cl::values(clEnumVal(m32, "32-bit"),
+                                         clEnumVal(m64, "64-bit (default)")));
+
+static cl::opt<std::string>
+TripleName("triple", cl::desc("Target triple to assemble for, "
+                              "see -version for available targets"));
+
+static cl::opt<std::string>
+DebugCompilationDir("fdebug-compilation-dir",
+                    cl::desc("Specifies the debug info's compilation dir"));
+
+static cl::list<std::string>
+DebugPrefixMap("fdebug-prefix-map",
+               cl::desc("Map file source paths in debug info"),
+               cl::value_desc("= separated key-value pairs"));
+
+static cl::opt<std::string>
+MainFileName("main-file-name",
+             cl::desc("Specifies the name we should consider the input file"));
+
+static cl::opt<bool> SaveTempLabels("save-temp-labels",
+                                    cl::desc("Don't discard temporary labels"));
+
+enum ActionType {
+  AC_AsLex,
+  AC_Assemble,
+  AC_Disassemble,
+  AC_MDisassemble,
+};
+
+static cl::opt<ActionType>
+Action(cl::desc("Action to perform:"),
+       cl::init(AC_Assemble),
+       cl::values(clEnumValN(AC_AsLex, "as-lex",
+                             "Lex tokens from a .asm file"),
+                  clEnumValN(AC_Assemble, "assemble",
+                             "Assemble a .asm file (default)"),
+                  clEnumValN(AC_Disassemble, "disassemble",
+                             "Disassemble strings of hex bytes"),
+                  clEnumValN(AC_MDisassemble, "mdis",
+                             "Marked up disassembly of strings of hex bytes")));
+
+static const Target *GetTarget(const char *ProgName) {
+  // Figure out the target triple.
+  if (TripleName.empty()) {
+    if (Bitness == m32)
+      TripleName = "i386-pc-windows";
+    else if (Bitness == m64)
+      TripleName = "x86_64-pc-windows";
+  }
+  Triple TheTriple(Triple::normalize(TripleName));
+
+  // Get the target specific parser.
+  std::string Error;
+  const Target *TheTarget = TargetRegistry::lookupTarget("", TheTriple, Error);
+  if (!TheTarget) {
+    WithColor::error(errs(), ProgName) << Error;
+    return nullptr;
+  }
+
+  // Update the triple name and return the found target.
+  TripleName = TheTriple.getTriple();
+  return TheTarget;
+}
+
+static std::unique_ptr<ToolOutputFile> GetOutputStream(StringRef Path) {
+  std::error_code EC;
+  auto Out = std::make_unique<ToolOutputFile>(Path, EC, sys::fs::F_None);
+  if (EC) {
+    WithColor::error() << EC.message() << '\n';
+    return nullptr;
+  }
+
+  return Out;
+}
+
+static int AsLexInput(SourceMgr &SrcMgr, MCAsmInfo &MAI,
+                      raw_ostream &OS) {
+  AsmLexer Lexer(MAI);
+  Lexer.setBuffer(SrcMgr.getMemoryBuffer(SrcMgr.getMainFileID())->getBuffer());
+
+  bool Error = false;
+  while (Lexer.Lex().isNot(AsmToken::Eof)) {
+    Lexer.getTok().dump(OS);
+    OS << "\n";
+    if (Lexer.getTok().getKind() == AsmToken::Error)
+      Error = true;
+  }
+
+  return Error;
+}
+
+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<MCTargetAsmParser> TAP(
+      TheTarget->createMCAsmParser(STI, *Parser, MCII, MCOptions));
+
+  if (!TAP) {
+    WithColor::error(errs(), ProgName)
+        << "this target does not support assembly parsing.\n";
+    return 1;
+  }
+
+  Parser->setShowParsedOperands(ShowInstOperands);
+  Parser->setTargetParser(*TAP);
+  Parser->getLexer().setLexMasmIntegers(true);
+
+  int Res = Parser->Run(/*NoInitialTextSection=*/true);
+
+  return Res;
+}
+
+int main(int argc, char **argv) {
+  InitLLVM X(argc, argv);
+
+  // Initialize targets and assembly printers/parsers.
+  llvm::InitializeAllTargetInfos();
+  llvm::InitializeAllTargetMCs();
+  llvm::InitializeAllAsmParsers();
+  llvm::InitializeAllDisassemblers();
+
+  // Register the target printer for --version.
+  cl::AddExtraVersionPrinter(TargetRegistry::printRegisteredTargetsForVersion);
+
+  cl::ParseCommandLineOptions(argc, argv, "llvm machine code playground\n");
+  MCTargetOptions MCOptions = InitMCTargetOptionsFromFlags();
+
+  const char *ProgName = argv[0];
+  const Target *TheTarget = GetTarget(ProgName);
+  if (!TheTarget)
+    return 1;
+  // Now that GetTarget() has (potentially) replaced TripleName, it's safe to
+  // construct the Triple object.
+  Triple TheTriple(TripleName);
+
+  ErrorOr<std::unique_ptr<MemoryBuffer>> BufferPtr =
+      MemoryBuffer::getFileOrSTDIN(InputFilename);
+  if (std::error_code EC = BufferPtr.getError()) {
+    WithColor::error(errs(), ProgName)
+        << InputFilename << ": " << EC.message() << '\n';
+    return 1;
+  }
+  MemoryBuffer *Buffer = BufferPtr->get();
+
+  SourceMgr SrcMgr;
+
+  // Tell SrcMgr about this buffer, which is what the parser will pick up.
+  SrcMgr.AddNewSourceBuffer(std::move(*BufferPtr), SMLoc());
+
+  // Record the location of the include directories so that the lexer can find
+  // it later.
+  SrcMgr.setIncludeDirs(IncludeDirs);
+
+  std::unique_ptr<MCRegisterInfo> MRI(TheTarget->createMCRegInfo(TripleName));
+  assert(MRI && "Unable to create target register info!");
+
+  std::unique_ptr<MCAsmInfo> MAI(
+      TheTarget->createMCAsmInfo(*MRI, TripleName, MCOptions));
+  assert(MAI && "Unable to create target asm info!");
+
+  MAI->setPreserveAsmComments(PreserveComments);
+
+  // FIXME: This is not pretty. MCContext has a ptr to MCObjectFileInfo and
+  // MCObjectFileInfo needs a MCContext reference in order to initialize itself.
+  MCObjectFileInfo MOFI;
+  MCContext Ctx(MAI.get(), MRI.get(), &MOFI, &SrcMgr);
+  MOFI.InitMCObjectFileInfo(TheTriple, /*PIC=*/false, Ctx,
+                            /*LargeCodeModel=*/true);
+
+  if (SaveTempLabels)
+    Ctx.setAllowTemporaryLabels(false);
+
+  if (!DebugCompilationDir.empty()) {
+    Ctx.setCompilationDir(DebugCompilationDir);
+  } else {
+    // If no compilation dir is set, try to use the current directory.
+    SmallString<128> CWD;
+    if (!sys::fs::current_path(CWD))
+      Ctx.setCompilationDir(CWD);
+  }
+  for (const auto &Arg : DebugPrefixMap) {
+    const auto &KV = StringRef(Arg).split('=');
+    Ctx.addDebugPrefixMapEntry(KV.first, KV.second);
+  }
+  if (!MainFileName.empty())
+    Ctx.setMainFileName(MainFileName);
+
+  // Package up features to be passed to target/subtarget
+  std::string FeaturesStr;
+  //if (MAttrs.size()) {
+    //SubtargetFeatures Features;
+    //for (unsigned i = 0; i != MAttrs.size(); ++i)
+      //Features.AddFeature(MAttrs[i]);
+    //FeaturesStr = Features.getString();
+  //}
+
+  std::unique_ptr<ToolOutputFile> Out = GetOutputStream(OutputFilename);
+  if (!Out)
+    return 1;
+
+  std::unique_ptr<buffer_ostream> BOS;
+  raw_pwrite_stream *OS = &Out->os();
+  std::unique_ptr<MCStreamer> Str;
+
+  std::unique_ptr<MCInstrInfo> MCII(TheTarget->createMCInstrInfo());
+  std::unique_ptr<MCSubtargetInfo> STI(
+      TheTarget->createMCSubtargetInfo(TripleName, /*CPU=*/"", FeaturesStr));
+
+  MCInstPrinter *IP = nullptr;
+  if (FileType == OFT_AssemblyFile) {
+    const unsigned OutputAsmVariant = OutputATTAsm ? 0U   // ATT dialect
+                                                   : 1U;  // Intel dialect
+    IP = TheTarget->createMCInstPrinter(Triple(TripleName), OutputAsmVariant,
+                                        *MAI, *MCII, *MRI);
+
+    if (!IP) {
+      WithColor::error()
+          << "unable to create instruction printer for target triple '"
+          << TheTriple.normalize() << "' with "
+          << (OutputATTAsm ? "ATT" : "Intel") << " assembly variant.\n";
+      return 1;
+    }
+
+    // Set the display preference for hex vs. decimal immediates.
+    IP->setPrintImmHex(PrintImmHex);
+
+    // Set up the AsmStreamer.
+    std::unique_ptr<MCCodeEmitter> CE;
+    if (ShowEncoding)
+      CE.reset(TheTarget->createMCCodeEmitter(*MCII, *MRI, Ctx));
+
+    std::unique_ptr<MCAsmBackend> MAB(
+        TheTarget->createMCAsmBackend(*STI, *MRI, MCOptions));
+    auto FOut = std::make_unique<formatted_raw_ostream>(*OS);
+    Str.reset(
+        TheTarget->createAsmStreamer(Ctx, std::move(FOut), /*asmverbose*/ true,
+                                     /*useDwarfDirectory*/ true, IP,
+                                     std::move(CE), std::move(MAB), ShowInst));
+
+  } else if (FileType == OFT_Null) {
+    Str.reset(TheTarget->createNullStreamer(Ctx));
+  } else {
+    assert(FileType == OFT_ObjectFile && "Invalid file type!");
+
+    // Don't waste memory on names of temp labels.
+    Ctx.setUseNamesOnTempLabels(false);
+
+    if (!Out->os().supportsSeeking()) {
+      BOS = std::make_unique<buffer_ostream>(Out->os());
+      OS = BOS.get();
+    }
+
+    MCCodeEmitter *CE = TheTarget->createMCCodeEmitter(*MCII, *MRI, Ctx);
+    MCAsmBackend *MAB = TheTarget->createMCAsmBackend(*STI, *MRI, MCOptions);
+    Str.reset(TheTarget->createMCObjectStreamer(
+        TheTriple, Ctx, std::unique_ptr<MCAsmBackend>(MAB),
+        MAB->createObjectWriter(*OS), std::unique_ptr<MCCodeEmitter>(CE), *STI,
+        MCOptions.MCRelaxAll, MCOptions.MCIncrementalLinkerCompatible,
+        /*DWARFMustBeAtTheEnd*/ false));
+    //if (NoExecStack)
+      //Str->InitSections(true);
+  }
+
+  // Use Assembler information for parsing.
+  Str->setUseAssemblerInfoForParsing(true);
+
+  int Res = 1;
+  bool disassemble = false;
+  switch (Action) {
+  case AC_AsLex:
+    Res = AsLexInput(SrcMgr, *MAI, Out->os());
+    break;
+  case AC_Assemble:
+    Res = AssembleInput(ProgName, TheTarget, SrcMgr, Ctx, *Str, *MAI, *STI,
+                        *MCII, MCOptions);
+    break;
+  case AC_MDisassemble:
+    assert(IP && "Expected assembly output");
+    IP->setUseMarkup(1);
+    disassemble = true;
+    break;
+  case AC_Disassemble:
+    disassemble = true;
+    break;
+  }
+  if (disassemble)
+    Res = Disassembler::disassemble(*TheTarget, TripleName, *STI, *Str,
+                                    *Buffer, SrcMgr, Out->os());
+
+  // Keep output if no errors.
+  if (Res == 0)
+    Out->keep();
+  return Res;
+}
diff --git a/llvm/utils/gn/secondary/llvm/test/BUILD.gn b/llvm/utils/gn/secondary/llvm/test/BUILD.gn
--- a/llvm/utils/gn/secondary/llvm/test/BUILD.gn
+++ b/llvm/utils/gn/secondary/llvm/test/BUILD.gn
@@ -225,6 +225,7 @@
     "//llvm/tools/llvm-lto2",
     "//llvm/tools/llvm-mc",
     "//llvm/tools/llvm-mca",
+    "//llvm/tools/llvm-ml",
     "//llvm/tools/llvm-modextract",
     "//llvm/tools/llvm-mt",
     "//llvm/tools/llvm-nm",
diff --git a/llvm/utils/gn/secondary/llvm/tools/llvm-ml/BUILD.gn b/llvm/utils/gn/secondary/llvm/tools/llvm-ml/BUILD.gn
new file mode 100644
--- /dev/null
+++ b/llvm/utils/gn/secondary/llvm/tools/llvm-ml/BUILD.gn
@@ -0,0 +1,17 @@
+executable("llvm-ml") {
+  deps = [
+    "//llvm/lib/MC",
+    "//llvm/lib/MC/MCParser",
+    "//llvm/lib/Support",
+    "//llvm/lib/Target:AllTargetsAsmParsers",
+    "//llvm/lib/Target:AllTargetsAsmPrinters",
+    "//llvm/lib/Target:AllTargetsDescs",
+    "//llvm/lib/Target:AllTargetsDisassemblers",
+    "//llvm/lib/Target:AllTargetsInfos",
+  ]
+  sources = [
+    # FIXME: duplicating this is stupid
+    "Disassembler.cpp",
+    "llvm-ml.cpp",
+  ]
+}