[clang-offload-bundler][NFC] Library-ize ClangOffloadBundler (1/4)

[lamb-j]

Summary

Lifting the core functionalities of the clang-offload-bundler into a
user-facing library/API. This will allow online and JIT compilers to
bundle and unbundle files without spawning a new process.

This NFC patch (1/4) lifts the classes and functions used to
implement the clang-offload-bundler into a separate
OffloadBundler.cpp, and defines three top-level API functions in
OfflaodBundler.h

BundleFiles()
UnbundleFiles()
UnbundleArchives()

In successive patches, we aim to:

1. Refactor global command-line option variables (cl::opt, cl::list, cl::bool, etc.) out of the API and into a Config class that can be passed as a local argument.
2. Refactor dependence on the bundler executable path into an optional parameter
3. Move OffloadBundler.cpp and OffloadBundler.h into clang/lib/Driver and clang/include/clang/Driver

[lamb-j]

Adding clang-format

[yaxunl]

I feel it is better to do the refactoring in one patch, since it is difficult to maintain the integrity of 4 patches. It would be easier to revert or cherry-pick the change.

[lamb-j]

@yaxunl Are you recommending I combine all 4 patches down into 1 patch? Or combine a subset of patches?

[jdoerfert]

Isn't the offload bundler on it's "way out" (=replaced and then deleted soon)?

[jhuber6]

In D129301#3637642, @jdoerfert wrote:

Isn't the offload bundler on it's "way out" (=replaced and then deleted soon)?

HIP still uses it to create their fatbinary format for CUDA-like support for multi-architecture binaries as well as their object file format. Once D128914 is landed we can at least compile HIP without it, but we would still need to use it to create the bundled image until AMD decides to support my stuff in their runtime. Beyond that I'm not aware of what the users will be now that OpenMP uses the new interface by default. I'm not in a big hurry to delete this if people still have a use for it, but I'd prefer things to use the new interface if possible. Are there any other situations where we still need the clang-offload-bundler? If there's anything the new interface is lacking I could add it in.

[yaxunl]

In D129301#3637664, @jhuber6 wrote:

In D129301#3637642, @jdoerfert wrote:

Isn't the offload bundler on it's "way out" (=replaced and then deleted soon)?

HIP still uses it to create their fatbinary format for CUDA-like support for multi-architecture binaries as well as their object file format. Once D128914 is landed we can at least compile HIP without it, but we would still need to use it to create the bundled image until AMD decides to support my stuff in their runtime. Beyond that I'm not aware of what the users will be now that OpenMP uses the new interface by default. I'm not in a big hurry to delete this if people still have a use for it, but I'd prefer things to use the new interface if possible. Are there any other situations where we still need the clang-offload-bundler? If there's anything the new interface is lacking I could add it in.

I think before the new binary format supports Windows and -fno-gpu-rdc and HIP runtime support the new binary format, we cannot deprecate clang-offload-bundler. I expect that would take some time.

[yaxunl]

In D129301#3637641, @lamb-j wrote:

@yaxunl Are you recommending I combine all 4 patches down into 1 patch? Or combine a subset of patches?

I recommend combining all patches as one.

[jhuber6]

In D129301#3639318, @yaxunl wrote:

I think before the new binary format supports Windows and -fno-gpu-rdc and HIP runtime support the new binary format, we cannot deprecate clang-offload-bundler. I expect that would take some time.

Supporting -fno-gpu-rdc should be easy, this will just require a few tweaks to the driver phases and passing it to the host backend directly. Supporting Windows would be a little tougher, we would need to make sure we can embed / extract the device code with Windows. After that we would need to synthesize the start / stop pointers differently. There is a way to do this on Windows similar to how Unix linkers, there's some examples in ASAN or HWSAN I believe. It's definitely doable but would take some effort, so it definitely won't work in time for the 15 release. I personally don't have much interest in Mac or Windows, but if I want to make this format universal I may need to actually sit down and implement it.

[lamb-j]

Abandoned in favor of combined patch: https://reviews.llvm.org/D129873

clang/tools/clang-offload-bundler/CMakeLists.txt

 set(LLVM_LINK_COMPONENTS Object Support)
 
 add_clang_tool(clang-offload-bundler
   ClangOffloadBundler.cpp
-  
+  OffloadBundler.cpp
   DEPENDS
   intrinsics_gen
   )
 
 set(CLANG_OFFLOAD_BUNDLER_LIB_DEPS
   clangBasic
   )
-  
 add_dependencies(clang clang-offload-bundler)
 
 clang_target_link_libraries(clang-offload-bundler
   PRIVATE
   ${CLANG_OFFLOAD_BUNDLER_LIB_DEPS}
   )

clang/tools/clang-offload-bundler/ClangOffloadBundler.cpp

 //===-- clang-offload-bundler/ClangOffloadBundler.cpp ---------------------===//
 //
 // 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 <cstddef>
 #include <cstdint>
 #include <forward_list>
 #include <memory>
 #include <set>
 #include <string>
 #include <system_error>
 #include <utility>
+#include "OffloadBundler.h"
 
 using namespace llvm;
 using namespace llvm::object;
 
 static cl::opt<bool> Help("h", cl::desc("Alias for -help"), cl::Hidden);
 
 // Mark all our options with this category, everything else (except for -version
 // and -help) will be hidden.
-static cl::OptionCategory
+cl::OptionCategory
     ClangOffloadBundlerCategory("clang-offload-bundler options");
-static cl::list<std::string>
-    InputFileNames("input",
+cl::list<std::string>
+    InputFileNames("input", cl::ZeroOrMore,
                    cl::desc("Input file."
                             " Can be specified multiple times "
                             "for multiple input files."),
                    cl::cat(ClangOffloadBundlerCategory));
 static cl::list<std::string>
-    InputFileNamesDeprecatedOpt("inputs", cl::CommaSeparated,
+    InputFileNamesDeprecatedOpt("inputs", cl::CommaSeparated, cl::ZeroOrMore,
                                 cl::desc("[<input file>,...] (deprecated)"),
                                 cl::cat(ClangOffloadBundlerCategory));
-static cl::list<std::string>
-    OutputFileNames("output",
+cl::list<std::string>
+    OutputFileNames("output", cl::ZeroOrMore,
                     cl::desc("Output file."
                              " Can be specified multiple times "
                              "for multiple output files."),
                     cl::cat(ClangOffloadBundlerCategory));
 static cl::list<std::string>
-    OutputFileNamesDeprecatedOpt("outputs", cl::CommaSeparated,
+    OutputFileNamesDeprecatedOpt("outputs", cl::CommaSeparated, cl::ZeroOrMore,
                                  cl::desc("[<output file>,...] (deprecated)"),
                                  cl::cat(ClangOffloadBundlerCategory));
-static cl::list<std::string>
+cl::list<std::string>
     TargetNames("targets", cl::CommaSeparated,
                 cl::desc("[<offload kind>-<target triple>,...]"),
                 cl::cat(ClangOffloadBundlerCategory));
-static cl::opt<std::string>
+cl::opt<std::string>
     FilesType("type", cl::Required,
               cl::desc("Type of the files to be bundled/unbundled.\n"
                        "Current supported types are:\n"
                        "  i   - cpp-output\n"
                        "  ii  - c++-cpp-output\n"
                        "  cui - cuda/hip-output\n"
                        "  d   - dependency\n"
                        "  ll  - llvm\n"
                        "  bc  - llvm-bc\n"
                        "  s   - assembler\n"
                        "  o   - object\n"
                        "  a   - archive of objects\n"
                        "  gch - precompiled-header\n"
                        "  ast - clang AST file"),
               cl::cat(ClangOffloadBundlerCategory));
-static cl::opt<bool>
+cl::opt<bool>
     Unbundle("unbundle",
              cl::desc("Unbundle bundled file into several output files.\n"),
              cl::init(false), cl::cat(ClangOffloadBundlerCategory));
 
-static cl::opt<bool>
+cl::opt<bool>
     ListBundleIDs("list", cl::desc("List bundle IDs in the bundled file.\n"),
                   cl::init(false), cl::cat(ClangOffloadBundlerCategory));
 
-static cl::opt<bool> PrintExternalCommands(
+cl::opt<bool> PrintExternalCommands(
     "###",
     cl::desc("Print any external commands that are to be executed "
              "instead of actually executing them - for testing purposes.\n"),
     cl::init(false), cl::cat(ClangOffloadBundlerCategory));
 
-static cl::opt<bool>
+cl::opt<bool>
     AllowMissingBundles("allow-missing-bundles",
                         cl::desc("Create empty files if bundles are missing "
                                  "when unbundling.\n"),
                         cl::init(false), cl::cat(ClangOffloadBundlerCategory));
 
-static cl::opt<unsigned>
+cl::opt<unsigned>
     BundleAlignment("bundle-align",
                     cl::desc("Alignment of bundle for binary files"),
                     cl::init(1), cl::cat(ClangOffloadBundlerCategory));
 
-static cl::opt<bool> HipOpenmpCompatible(
+cl::opt<bool> HipOpenmpCompatible(
     "hip-openmp-compatible",
     cl::desc("Treat hip and hipv4 offload kinds as "
              "compatible with openmp kind, and vice versa.\n"),
     cl::init(false), cl::cat(ClangOffloadBundlerCategory));
 
-/// Magic string that marks the existence of offloading data.
-#define OFFLOAD_BUNDLER_MAGIC_STR "__CLANG_OFFLOAD_BUNDLE__"
-
 /// The index of the host input in the list of inputs.
-static unsigned HostInputIndex = ~0u;
+unsigned HostInputIndex = ~0u;
 
 /// Whether not having host target is allowed.
-static bool AllowNoHost = false;
+bool AllowNoHost = false;
 
 /// Path to the current binary.
-static std::string BundlerExecutable;
-
-/// Obtain the offload kind, real machine triple, and an optional GPUArch
-/// out of the target information specified by the user.
-/// Bundle Entry ID (or, Offload Target String) has following components:
-///  * Offload Kind - Host, OpenMP, or HIP
-///  * Triple - Standard LLVM Triple
-///  * GPUArch (Optional) - Processor name, like gfx906 or sm_30
-
-struct OffloadTargetInfo {
-  StringRef OffloadKind;
-  llvm::Triple Triple;
-  StringRef GPUArch;
-
-  OffloadTargetInfo(const StringRef Target) {
-    auto TargetFeatures = Target.split(':');
-    auto TripleOrGPU = TargetFeatures.first.rsplit('-');
-
-    if (clang::StringToCudaArch(TripleOrGPU.second) !=
-        clang::CudaArch::UNKNOWN) {
-      auto KindTriple = TripleOrGPU.first.split('-');
-      this->OffloadKind = KindTriple.first;
-      this->Triple = llvm::Triple(KindTriple.second);
-      this->GPUArch = Target.substr(Target.find(TripleOrGPU.second));
-    } else {
-      auto KindTriple = TargetFeatures.first.split('-');
-      this->OffloadKind = KindTriple.first;
-      this->Triple = llvm::Triple(KindTriple.second);
-      this->GPUArch = "";
-    }
-  }
-
-  bool hasHostKind() const { return this->OffloadKind == "host"; }
-
-  bool isOffloadKindValid() const {
-    return OffloadKind == "host" || OffloadKind == "openmp" ||
-           OffloadKind == "hip" || OffloadKind == "hipv4";
-  }
-
-  bool isOffloadKindCompatible(const StringRef TargetOffloadKind) const {
-    if (OffloadKind == TargetOffloadKind)
-      return true;
-    if (HipOpenmpCompatible) {
-      bool HIPCompatibleWithOpenMP =
-          OffloadKind.startswith_insensitive("hip") &&
-          TargetOffloadKind == "openmp";
-      bool OpenMPCompatibleWithHIP =
-          OffloadKind == "openmp" &&
-          TargetOffloadKind.startswith_insensitive("hip");
-      return HIPCompatibleWithOpenMP || OpenMPCompatibleWithHIP;
-    }
-    return false;
-  }
-
-  bool isTripleValid() const {
-    return !Triple.str().empty() && Triple.getArch() != Triple::UnknownArch;
-  }
-
-  bool operator==(const OffloadTargetInfo &Target) const {
-    return OffloadKind == Target.OffloadKind &&
-           Triple.isCompatibleWith(Target.Triple) && GPUArch == Target.GPUArch;
-  }
-
-  std::string str() {
-    return Twine(OffloadKind + "-" + Triple.str() + "-" + GPUArch).str();
-  }
-};
-
-static StringRef getDeviceFileExtension(StringRef Device,
-                                        StringRef BundleFileName) {
-  if (Device.contains("gfx"))
-    return ".bc";
-  if (Device.contains("sm_"))
-    return ".cubin";
-  return sys::path::extension(BundleFileName);
-}
-
-static std::string getDeviceLibraryFileName(StringRef BundleFileName,
-                                            StringRef Device) {
-  StringRef LibName = sys::path::stem(BundleFileName);
-  StringRef Extension = getDeviceFileExtension(Device, BundleFileName);
-
-  std::string Result;
-  Result += LibName;
-  Result += Extension;
-  return Result;
-}
-
-/// Generic file handler interface.
-class FileHandler {
-public:
-  struct BundleInfo {
-    StringRef BundleID;
-  };
-
-  FileHandler() {}
-
-  virtual ~FileHandler() {}
-
-  /// Update the file handler with information from the header of the bundled
-  /// file.
-  virtual Error ReadHeader(MemoryBuffer &Input) = 0;
-
-  /// Read the marker of the next bundled to be read in the file. The bundle
-  /// name is returned if there is one in the file, or `None` if there are no
-  /// more bundles to be read.
-  virtual Expected<Optional<StringRef>>
-  ReadBundleStart(MemoryBuffer &Input) = 0;
-
-  /// Read the marker that closes the current bundle.
-  virtual Error ReadBundleEnd(MemoryBuffer &Input) = 0;
-
-  /// Read the current bundle and write the result into the stream \a OS.
-  virtual Error ReadBundle(raw_ostream &OS, MemoryBuffer &Input) = 0;
-
-  /// Write the header of the bundled file to \a OS based on the information
-  /// gathered from \a Inputs.
-  virtual Error WriteHeader(raw_fd_ostream &OS,
-                            ArrayRef<std::unique_ptr<MemoryBuffer>> Inputs) = 0;
-
-  /// Write the marker that initiates a bundle for the triple \a TargetTriple to
-  /// \a OS.
-  virtual Error WriteBundleStart(raw_fd_ostream &OS,
-                                 StringRef TargetTriple) = 0;
-
-  /// Write the marker that closes a bundle for the triple \a TargetTriple to \a
-  /// OS.
-  virtual Error WriteBundleEnd(raw_fd_ostream &OS, StringRef TargetTriple) = 0;
-
-  /// Write the bundle from \a Input into \a OS.
-  virtual Error WriteBundle(raw_fd_ostream &OS, MemoryBuffer &Input) = 0;
-
-  /// List bundle IDs in \a Input.
-  virtual Error listBundleIDs(MemoryBuffer &Input) {
-    if (Error Err = ReadHeader(Input))
-      return Err;
-
-    return forEachBundle(Input, [&](const BundleInfo &Info) -> Error {
-      llvm::outs() << Info.BundleID << '\n';
-      Error Err = listBundleIDsCallback(Input, Info);
-      if (Err)
-        return Err;
-      return Error::success();
-    });
-  }
-
-  /// For each bundle in \a Input, do \a Func.
-  Error forEachBundle(MemoryBuffer &Input,
-                      std::function<Error(const BundleInfo &)> Func) {
-    while (true) {
-      Expected<Optional<StringRef>> CurTripleOrErr = ReadBundleStart(Input);
-      if (!CurTripleOrErr)
-        return CurTripleOrErr.takeError();
-
-      // No more bundles.
-      if (!*CurTripleOrErr)
-        break;
-
-      StringRef CurTriple = **CurTripleOrErr;
-      assert(!CurTriple.empty());
-
-      BundleInfo Info{CurTriple};
-      if (Error Err = Func(Info))
-        return Err;
-    }
-    return Error::success();
-  }
-
-protected:
-  virtual Error listBundleIDsCallback(MemoryBuffer &Input,
-                                      const BundleInfo &Info) {
-    return Error::success();
-  }
-};
-
-/// Handler for binary files. The bundled file will have the following format
-/// (all integers are stored in little-endian format):
-///
-/// "OFFLOAD_BUNDLER_MAGIC_STR" (ASCII encoding of the string)
-///
-/// NumberOfOffloadBundles (8-byte integer)
-///
-/// OffsetOfBundle1 (8-byte integer)
-/// SizeOfBundle1 (8-byte integer)
-/// NumberOfBytesInTripleOfBundle1 (8-byte integer)
-/// TripleOfBundle1 (byte length defined before)
-///
-/// ...
-///
-/// OffsetOfBundleN (8-byte integer)
-/// SizeOfBundleN (8-byte integer)
-/// NumberOfBytesInTripleOfBundleN (8-byte integer)
-/// TripleOfBundleN (byte length defined before)
-///
-/// Bundle1
-/// ...
-/// BundleN
-
-/// Read 8-byte integers from a buffer in little-endian format.
-static uint64_t Read8byteIntegerFromBuffer(StringRef Buffer, size_t pos) {
-  uint64_t Res = 0;
-  const char *Data = Buffer.data();
-
-  for (unsigned i = 0; i < 8; ++i) {
-    Res <<= 8;
-    uint64_t Char = (uint64_t)Data[pos + 7 - i];
-    Res |= 0xffu & Char;
-  }
-  return Res;
-}
-
-/// Write 8-byte integers to a buffer in little-endian format.
-static void Write8byteIntegerToBuffer(raw_fd_ostream &OS, uint64_t Val) {
-  for (unsigned i = 0; i < 8; ++i) {
-    char Char = (char)(Val & 0xffu);
-    OS.write(&Char, 1);
-    Val >>= 8;
-  }
-}
-
-class BinaryFileHandler final : public FileHandler {
-  /// Information about the bundles extracted from the header.
-  struct BinaryBundleInfo final : public BundleInfo {
-    /// Size of the bundle.
-    uint64_t Size = 0u;
-    /// Offset at which the bundle starts in the bundled file.
-    uint64_t Offset = 0u;
-
-    BinaryBundleInfo() {}
-    BinaryBundleInfo(uint64_t Size, uint64_t Offset)
-        : Size(Size), Offset(Offset) {}
-  };
-
-  /// Map between a triple and the corresponding bundle information.
-  StringMap<BinaryBundleInfo> BundlesInfo;
-
-  /// Iterator for the bundle information that is being read.
-  StringMap<BinaryBundleInfo>::iterator CurBundleInfo;
-  StringMap<BinaryBundleInfo>::iterator NextBundleInfo;
-
-  /// Current bundle target to be written.
-  std::string CurWriteBundleTarget;
-
-public:
-  BinaryFileHandler() {}
-
-  ~BinaryFileHandler() final {}
-
-  Error ReadHeader(MemoryBuffer &Input) final {
-    StringRef FC = Input.getBuffer();
-
-    // Initialize the current bundle with the end of the container.
-    CurBundleInfo = BundlesInfo.end();
-
-    // Check if buffer is smaller than magic string.
-    size_t ReadChars = sizeof(OFFLOAD_BUNDLER_MAGIC_STR) - 1;
-    if (ReadChars > FC.size())
-      return Error::success();
-
-    // Check if no magic was found.
-    StringRef Magic(FC.data(), sizeof(OFFLOAD_BUNDLER_MAGIC_STR) - 1);
-    if (!Magic.equals(OFFLOAD_BUNDLER_MAGIC_STR))
-      return Error::success();
-
-    // Read number of bundles.
-    if (ReadChars + 8 > FC.size())
-      return Error::success();
-
-    uint64_t NumberOfBundles = Read8byteIntegerFromBuffer(FC, ReadChars);
-    ReadChars += 8;
-
-    // Read bundle offsets, sizes and triples.
-    for (uint64_t i = 0; i < NumberOfBundles; ++i) {
-
-      // Read offset.
-      if (ReadChars + 8 > FC.size())
-        return Error::success();
-
-      uint64_t Offset = Read8byteIntegerFromBuffer(FC, ReadChars);
-      ReadChars += 8;
-
-      // Read size.
-      if (ReadChars + 8 > FC.size())
-        return Error::success();
-
-      uint64_t Size = Read8byteIntegerFromBuffer(FC, ReadChars);
-      ReadChars += 8;
-
-      // Read triple size.
-      if (ReadChars + 8 > FC.size())
-        return Error::success();
-
-      uint64_t TripleSize = Read8byteIntegerFromBuffer(FC, ReadChars);
-      ReadChars += 8;
-
-      // Read triple.
-      if (ReadChars + TripleSize > FC.size())
-        return Error::success();
-
-      StringRef Triple(&FC.data()[ReadChars], TripleSize);
-      ReadChars += TripleSize;
-
-      // Check if the offset and size make sense.
-      if (!Offset || Offset + Size > FC.size())
-        return Error::success();
-
-      assert(BundlesInfo.find(Triple) == BundlesInfo.end() &&
-             "Triple is duplicated??");
-      BundlesInfo[Triple] = BinaryBundleInfo(Size, Offset);
-    }
-    // Set the iterator to where we will start to read.
-    CurBundleInfo = BundlesInfo.end();
-    NextBundleInfo = BundlesInfo.begin();
-    return Error::success();
-  }
-
-  Expected<Optional<StringRef>> ReadBundleStart(MemoryBuffer &Input) final {
-    if (NextBundleInfo == BundlesInfo.end())
-      return None;
-    CurBundleInfo = NextBundleInfo++;
-    return CurBundleInfo->first();
-  }
-
-  Error ReadBundleEnd(MemoryBuffer &Input) final {
-    assert(CurBundleInfo != BundlesInfo.end() && "Invalid reader info!");
-    return Error::success();
-  }
-
-  Error ReadBundle(raw_ostream &OS, MemoryBuffer &Input) final {
-    assert(CurBundleInfo != BundlesInfo.end() && "Invalid reader info!");
-    StringRef FC = Input.getBuffer();
-    OS.write(FC.data() + CurBundleInfo->second.Offset,
-             CurBundleInfo->second.Size);
-    return Error::success();
-  }
-
-  Error WriteHeader(raw_fd_ostream &OS,
-                    ArrayRef<std::unique_ptr<MemoryBuffer>> Inputs) final {
-    // Compute size of the header.
-    uint64_t HeaderSize = 0;
-
-    HeaderSize += sizeof(OFFLOAD_BUNDLER_MAGIC_STR) - 1;
-    HeaderSize += 8; // Number of Bundles
-
-    for (auto &T : TargetNames) {
-      HeaderSize += 3 * 8; // Bundle offset, Size of bundle and size of triple.
-      HeaderSize += T.size(); // The triple.
-    }
-
-    // Write to the buffer the header.
-    OS << OFFLOAD_BUNDLER_MAGIC_STR;
-
-    Write8byteIntegerToBuffer(OS, TargetNames.size());
-
-    unsigned Idx = 0;
-    for (auto &T : TargetNames) {
-      MemoryBuffer &MB = *Inputs[Idx++];
-      HeaderSize = alignTo(HeaderSize, BundleAlignment);
-      // Bundle offset.
-      Write8byteIntegerToBuffer(OS, HeaderSize);
-      // Size of the bundle (adds to the next bundle's offset)
-      Write8byteIntegerToBuffer(OS, MB.getBufferSize());
-      BundlesInfo[T] = BinaryBundleInfo(MB.getBufferSize(), HeaderSize);
-      HeaderSize += MB.getBufferSize();
-      // Size of the triple
-      Write8byteIntegerToBuffer(OS, T.size());
-      // Triple
-      OS << T;
-    }
-    return Error::success();
-  }
-
-  Error WriteBundleStart(raw_fd_ostream &OS, StringRef TargetTriple) final {
-    CurWriteBundleTarget = TargetTriple.str();
-    return Error::success();
-  }
-
-  Error WriteBundleEnd(raw_fd_ostream &OS, StringRef TargetTriple) final {
-    return Error::success();
-  }
-
-  Error WriteBundle(raw_fd_ostream &OS, MemoryBuffer &Input) final {
-    auto BI = BundlesInfo[CurWriteBundleTarget];
-    OS.seek(BI.Offset);
-    OS.write(Input.getBufferStart(), Input.getBufferSize());
-    return Error::success();
-  }
-};
-
-namespace {
-
-// This class implements a list of temporary files that are removed upon
-// object destruction.
-class TempFileHandlerRAII {
-public:
-  ~TempFileHandlerRAII() {
-    for (const auto &File : Files)
-      sys::fs::remove(File);
-  }
-
-  // Creates temporary file with given contents.
-  Expected<StringRef> Create(Optional<ArrayRef<char>> Contents) {
-    SmallString<128u> File;
-    if (std::error_code EC =
-            sys::fs::createTemporaryFile("clang-offload-bundler", "tmp", File))
-      return createFileError(File, EC);
-    Files.push_front(File);
-
-    if (Contents) {
-      std::error_code EC;
-      raw_fd_ostream OS(File, EC);
-      if (EC)
-        return createFileError(File, EC);
-      OS.write(Contents->data(), Contents->size());
-    }
-    return Files.front().str();
-  }
-
-private:
-  std::forward_list<SmallString<128u>> Files;
-};
-
-} // end anonymous namespace
-
-/// Handler for object files. The bundles are organized by sections with a
-/// designated name.
-///
-/// To unbundle, we just copy the contents of the designated section.
-class ObjectFileHandler final : public FileHandler {
-
-  /// The object file we are currently dealing with.
-  std::unique_ptr<ObjectFile> Obj;
-
-  /// Return the input file contents.
-  StringRef getInputFileContents() const { return Obj->getData(); }
-
-  /// Return bundle name (<kind>-<triple>) if the provided section is an offload
-  /// section.
-  static Expected<Optional<StringRef>> IsOffloadSection(SectionRef CurSection) {
-    Expected<StringRef> NameOrErr = CurSection.getName();
-    if (!NameOrErr)
-      return NameOrErr.takeError();
-
-    // If it does not start with the reserved suffix, just skip this section.
-    if (!NameOrErr->startswith(OFFLOAD_BUNDLER_MAGIC_STR))
-      return None;
-
-    // Return the triple that is right after the reserved prefix.
-    return NameOrErr->substr(sizeof(OFFLOAD_BUNDLER_MAGIC_STR) - 1);
-  }
-
-  /// Total number of inputs.
-  unsigned NumberOfInputs = 0;
-
-  /// Total number of processed inputs, i.e, inputs that were already
-  /// read from the buffers.
-  unsigned NumberOfProcessedInputs = 0;
-
-  /// Iterator of the current and next section.
-  section_iterator CurrentSection;
-  section_iterator NextSection;
-
-public:
-  ObjectFileHandler(std::unique_ptr<ObjectFile> ObjIn)
-      : Obj(std::move(ObjIn)), CurrentSection(Obj->section_begin()),
-        NextSection(Obj->section_begin()) {}
-
-  ~ObjectFileHandler() final {}
-
-  Error ReadHeader(MemoryBuffer &Input) final { return Error::success(); }
-
-  Expected<Optional<StringRef>> ReadBundleStart(MemoryBuffer &Input) final {
-    while (NextSection != Obj->section_end()) {
-      CurrentSection = NextSection;
-      ++NextSection;
-
-      // Check if the current section name starts with the reserved prefix. If
-      // so, return the triple.
-      Expected<Optional<StringRef>> TripleOrErr =
-          IsOffloadSection(*CurrentSection);
-      if (!TripleOrErr)
-        return TripleOrErr.takeError();
-      if (*TripleOrErr)
-        return **TripleOrErr;
-    }
-    return None;
-  }
-
-  Error ReadBundleEnd(MemoryBuffer &Input) final { return Error::success(); }
-
-  Error ReadBundle(raw_ostream &OS, MemoryBuffer &Input) final {
-    Expected<StringRef> ContentOrErr = CurrentSection->getContents();
-    if (!ContentOrErr)
-      return ContentOrErr.takeError();
-    StringRef Content = *ContentOrErr;
-
-    // Copy fat object contents to the output when extracting host bundle.
-    if (Content.size() == 1u && Content.front() == 0)
-      Content = StringRef(Input.getBufferStart(), Input.getBufferSize());
-
-    OS.write(Content.data(), Content.size());
-    return Error::success();
-  }
-
-  Error WriteHeader(raw_fd_ostream &OS,
-                    ArrayRef<std::unique_ptr<MemoryBuffer>> Inputs) final {
-    assert(HostInputIndex != ~0u && "Host input index not defined.");
-
-    // Record number of inputs.
-    NumberOfInputs = Inputs.size();
-    return Error::success();
-  }
-
-  Error WriteBundleStart(raw_fd_ostream &OS, StringRef TargetTriple) final {
-    ++NumberOfProcessedInputs;
-    return Error::success();
-  }
-
-  Error WriteBundleEnd(raw_fd_ostream &OS, StringRef TargetTriple) final {
-    assert(NumberOfProcessedInputs <= NumberOfInputs &&
-           "Processing more inputs that actually exist!");
-    assert(HostInputIndex != ~0u && "Host input index not defined.");
-
-    // If this is not the last output, we don't have to do anything.
-    if (NumberOfProcessedInputs != NumberOfInputs)
-      return Error::success();
-
-    // We will use llvm-objcopy to add target objects sections to the output
-    // fat object. These sections should have 'exclude' flag set which tells
-    // link editor to remove them from linker inputs when linking executable or
-    // shared library.
-
-    // Find llvm-objcopy in order to create the bundle binary.
-    ErrorOr<std::string> Objcopy = sys::findProgramByName(
-        "llvm-objcopy", sys::path::parent_path(BundlerExecutable));
-    if (!Objcopy)
-      Objcopy = sys::findProgramByName("llvm-objcopy");
-    if (!Objcopy)
-      return createStringError(Objcopy.getError(),
-                               "unable to find 'llvm-objcopy' in path");
-
-    // We write to the output file directly. So, we close it and use the name
-    // to pass down to llvm-objcopy.
-    OS.close();
-
-    // Temporary files that need to be removed.
-    TempFileHandlerRAII TempFiles;
-
-    // Compose llvm-objcopy command line for add target objects' sections with
-    // appropriate flags.
-    BumpPtrAllocator Alloc;
-    StringSaver SS{Alloc};
-    SmallVector<StringRef, 8u> ObjcopyArgs{"llvm-objcopy"};
-    for (unsigned I = 0; I < NumberOfInputs; ++I) {
-      StringRef InputFile = InputFileNames[I];
-      if (I == HostInputIndex) {
-        // Special handling for the host bundle. We do not need to add a
-        // standard bundle for the host object since we are going to use fat
-        // object as a host object. Therefore use dummy contents (one zero byte)
-        // when creating section for the host bundle.
-        Expected<StringRef> TempFileOrErr = TempFiles.Create(ArrayRef<char>(0));
-        if (!TempFileOrErr)
-          return TempFileOrErr.takeError();
-        InputFile = *TempFileOrErr;
-      }
-
-      ObjcopyArgs.push_back(SS.save(Twine("--add-section=") +
-                                    OFFLOAD_BUNDLER_MAGIC_STR + TargetNames[I] +
-                                    "=" + InputFile));
-      ObjcopyArgs.push_back(SS.save(Twine("--set-section-flags=") +
-                                    OFFLOAD_BUNDLER_MAGIC_STR + TargetNames[I] +
-                                    "=readonly,exclude"));
-    }
-    ObjcopyArgs.push_back("--");
-    ObjcopyArgs.push_back(InputFileNames[HostInputIndex]);
-    ObjcopyArgs.push_back(OutputFileNames.front());
-
-    if (Error Err = executeObjcopy(*Objcopy, ObjcopyArgs))
-      return Err;
-
-    return Error::success();
-  }
-
-  Error WriteBundle(raw_fd_ostream &OS, MemoryBuffer &Input) final {
-    return Error::success();
-  }
-
-private:
-  static Error executeObjcopy(StringRef Objcopy, ArrayRef<StringRef> Args) {
-    // If the user asked for the commands to be printed out, we do that
-    // instead of executing it.
-    if (PrintExternalCommands) {
-      errs() << "\"" << Objcopy << "\"";
-      for (StringRef Arg : drop_begin(Args, 1))
-        errs() << " \"" << Arg << "\"";
-      errs() << "\n";
-    } else {
-      if (sys::ExecuteAndWait(Objcopy, Args))
-        return createStringError(inconvertibleErrorCode(),
-                                 "'llvm-objcopy' tool failed");
-    }
-    return Error::success();
-  }
-};
-
-/// Handler for text files. The bundled file will have the following format.
-///
-/// "Comment OFFLOAD_BUNDLER_MAGIC_STR__START__ triple"
-/// Bundle 1
-/// "Comment OFFLOAD_BUNDLER_MAGIC_STR__END__ triple"
-/// ...
-/// "Comment OFFLOAD_BUNDLER_MAGIC_STR__START__ triple"
-/// Bundle N
-/// "Comment OFFLOAD_BUNDLER_MAGIC_STR__END__ triple"
-class TextFileHandler final : public FileHandler {
-  /// String that begins a line comment.
-  StringRef Comment;
-
-  /// String that initiates a bundle.
-  std::string BundleStartString;
-
-  /// String that closes a bundle.
-  std::string BundleEndString;
-
-  /// Number of chars read from input.
-  size_t ReadChars = 0u;
-
-protected:
-  Error ReadHeader(MemoryBuffer &Input) final { return Error::success(); }
-
-  Expected<Optional<StringRef>> ReadBundleStart(MemoryBuffer &Input) final {
-    StringRef FC = Input.getBuffer();
-
-    // Find start of the bundle.
-    ReadChars = FC.find(BundleStartString, ReadChars);
-    if (ReadChars == FC.npos)
-      return None;
-
-    // Get position of the triple.
-    size_t TripleStart = ReadChars = ReadChars + BundleStartString.size();
-
-    // Get position that closes the triple.
-    size_t TripleEnd = ReadChars = FC.find("\n", ReadChars);
-    if (TripleEnd == FC.npos)
-      return None;
-
-    // Next time we read after the new line.
-    ++ReadChars;
-
-    return StringRef(&FC.data()[TripleStart], TripleEnd - TripleStart);
-  }
-
-  Error ReadBundleEnd(MemoryBuffer &Input) final {
-    StringRef FC = Input.getBuffer();
-
-    // Read up to the next new line.
-    assert(FC[ReadChars] == '\n' && "The bundle should end with a new line.");
-
-    size_t TripleEnd = ReadChars = FC.find("\n", ReadChars + 1);
-    if (TripleEnd != FC.npos)
-      // Next time we read after the new line.
-      ++ReadChars;
-
-    return Error::success();
-  }
-
-  Error ReadBundle(raw_ostream &OS, MemoryBuffer &Input) final {
-    StringRef FC = Input.getBuffer();
-    size_t BundleStart = ReadChars;
-
-    // Find end of the bundle.
-    size_t BundleEnd = ReadChars = FC.find(BundleEndString, ReadChars);
-
-    StringRef Bundle(&FC.data()[BundleStart], BundleEnd - BundleStart);
-    OS << Bundle;
-
-    return Error::success();
-  }
-
-  Error WriteHeader(raw_fd_ostream &OS,
-                    ArrayRef<std::unique_ptr<MemoryBuffer>> Inputs) final {
-    return Error::success();
-  }
-
-  Error WriteBundleStart(raw_fd_ostream &OS, StringRef TargetTriple) final {
-    OS << BundleStartString << TargetTriple << "\n";
-    return Error::success();
-  }
-
-  Error WriteBundleEnd(raw_fd_ostream &OS, StringRef TargetTriple) final {
-    OS << BundleEndString << TargetTriple << "\n";
-    return Error::success();
-  }
-
-  Error WriteBundle(raw_fd_ostream &OS, MemoryBuffer &Input) final {
-    OS << Input.getBuffer();
-    return Error::success();
-  }
-
-public:
-  TextFileHandler(StringRef Comment) : Comment(Comment), ReadChars(0) {
-    BundleStartString =
-        "\n" + Comment.str() + " " OFFLOAD_BUNDLER_MAGIC_STR "__START__ ";
-    BundleEndString =
-        "\n" + Comment.str() + " " OFFLOAD_BUNDLER_MAGIC_STR "__END__ ";
-  }
-
-  Error listBundleIDsCallback(MemoryBuffer &Input,
-                              const BundleInfo &Info) final {
-    // TODO: To list bundle IDs in a bundled text file we need to go through
-    // all bundles. The format of bundled text file may need to include a
-    // header if the performance of listing bundle IDs of bundled text file is
-    // important.
-    ReadChars = Input.getBuffer().find(BundleEndString, ReadChars);
-    if (Error Err = ReadBundleEnd(Input))
-      return Err;
-    return Error::success();
-  }
-};
-
-/// Return an appropriate object file handler. We use the specific object
-/// handler if we know how to deal with that format, otherwise we use a default
-/// binary file handler.
-static std::unique_ptr<FileHandler>
-CreateObjectFileHandler(MemoryBuffer &FirstInput) {
-  // Check if the input file format is one that we know how to deal with.
-  Expected<std::unique_ptr<Binary>> BinaryOrErr = createBinary(FirstInput);
-
-  // We only support regular object files. If failed to open the input as a
-  // known binary or this is not an object file use the default binary handler.
-  if (errorToBool(BinaryOrErr.takeError()) || !isa<ObjectFile>(*BinaryOrErr))
-    return std::make_unique<BinaryFileHandler>();
-
-  // Otherwise create an object file handler. The handler will be owned by the
-  // client of this function.
-  return std::make_unique<ObjectFileHandler>(
-      std::unique_ptr<ObjectFile>(cast<ObjectFile>(BinaryOrErr->release())));
-}
-
-/// Return an appropriate handler given the input files and options.
-static Expected<std::unique_ptr<FileHandler>>
-CreateFileHandler(MemoryBuffer &FirstInput) {
-  if (FilesType == "i")
-    return std::make_unique<TextFileHandler>(/*Comment=*/"//");
-  if (FilesType == "ii")
-    return std::make_unique<TextFileHandler>(/*Comment=*/"//");
-  if (FilesType == "cui")
-    return std::make_unique<TextFileHandler>(/*Comment=*/"//");
-  // TODO: `.d` should be eventually removed once `-M` and its variants are
-  // handled properly in offload compilation.
-  if (FilesType == "d")
-    return std::make_unique<TextFileHandler>(/*Comment=*/"#");
-  if (FilesType == "ll")
-    return std::make_unique<TextFileHandler>(/*Comment=*/";");
-  if (FilesType == "bc")
-    return std::make_unique<BinaryFileHandler>();
-  if (FilesType == "s")
-    return std::make_unique<TextFileHandler>(/*Comment=*/"#");
-  if (FilesType == "o")
-    return CreateObjectFileHandler(FirstInput);
-  if (FilesType == "a")
-    return CreateObjectFileHandler(FirstInput);
-  if (FilesType == "gch")
-    return std::make_unique<BinaryFileHandler>();
-  if (FilesType == "ast")
-    return std::make_unique<BinaryFileHandler>();
-
-  return createStringError(errc::invalid_argument,
-                           "'" + FilesType + "': invalid file type specified");
-}
-
-/// Bundle the files. Return true if an error was found.
-static Error BundleFiles() {
-  std::error_code EC;
-
-  // Create output file.
-  raw_fd_ostream OutputFile(OutputFileNames.front(), EC, sys::fs::OF_None);
-  if (EC)
-    return createFileError(OutputFileNames.front(), EC);
-
-  // Open input files.
-  SmallVector<std::unique_ptr<MemoryBuffer>, 8u> InputBuffers;
-  InputBuffers.reserve(InputFileNames.size());
-  for (auto &I : InputFileNames) {
-    ErrorOr<std::unique_ptr<MemoryBuffer>> CodeOrErr =
-        MemoryBuffer::getFileOrSTDIN(I);
-    if (std::error_code EC = CodeOrErr.getError())
-      return createFileError(I, EC);
-    InputBuffers.emplace_back(std::move(*CodeOrErr));
-  }
-
-  // Get the file handler. We use the host buffer as reference.
-  assert((HostInputIndex != ~0u || AllowNoHost) &&
-         "Host input index undefined??");
-  Expected<std::unique_ptr<FileHandler>> FileHandlerOrErr =
-      CreateFileHandler(*InputBuffers[AllowNoHost ? 0 : HostInputIndex]);
-  if (!FileHandlerOrErr)
-    return FileHandlerOrErr.takeError();
-
-  std::unique_ptr<FileHandler> &FH = *FileHandlerOrErr;
-  assert(FH);
-
-  // Write header.
-  if (Error Err = FH->WriteHeader(OutputFile, InputBuffers))
-    return Err;
-
-  // Write all bundles along with the start/end markers. If an error was found
-  // writing the end of the bundle component, abort the bundle writing.
-  auto Input = InputBuffers.begin();
-  for (auto &Triple : TargetNames) {
-    if (Error Err = FH->WriteBundleStart(OutputFile, Triple))
-      return Err;
-    if (Error Err = FH->WriteBundle(OutputFile, **Input))
-      return Err;
-    if (Error Err = FH->WriteBundleEnd(OutputFile, Triple))
-      return Err;
-    ++Input;
-  }
-  return Error::success();
-}
-
-// List bundle IDs. Return true if an error was found.
-static Error ListBundleIDsInFile(StringRef InputFileName) {
-  // Open Input file.
-  ErrorOr<std::unique_ptr<MemoryBuffer>> CodeOrErr =
-      MemoryBuffer::getFileOrSTDIN(InputFileName);
-  if (std::error_code EC = CodeOrErr.getError())
-    return createFileError(InputFileName, EC);
-
-  MemoryBuffer &Input = **CodeOrErr;
-
-  // Select the right files handler.
-  Expected<std::unique_ptr<FileHandler>> FileHandlerOrErr =
-      CreateFileHandler(Input);
-  if (!FileHandlerOrErr)
-    return FileHandlerOrErr.takeError();
-
-  std::unique_ptr<FileHandler> &FH = *FileHandlerOrErr;
-  assert(FH);
-  return FH->listBundleIDs(Input);
-}
-
-// Unbundle the files. Return true if an error was found.
-static Error UnbundleFiles() {
-  // Open Input file.
-  ErrorOr<std::unique_ptr<MemoryBuffer>> CodeOrErr =
-      MemoryBuffer::getFileOrSTDIN(InputFileNames.front());
-  if (std::error_code EC = CodeOrErr.getError())
-    return createFileError(InputFileNames.front(), EC);
-
-  MemoryBuffer &Input = **CodeOrErr;
-
-  // Select the right files handler.
-  Expected<std::unique_ptr<FileHandler>> FileHandlerOrErr =
-      CreateFileHandler(Input);
-  if (!FileHandlerOrErr)
-    return FileHandlerOrErr.takeError();
-
-  std::unique_ptr<FileHandler> &FH = *FileHandlerOrErr;
-  assert(FH);
-
-  // Read the header of the bundled file.
-  if (Error Err = FH->ReadHeader(Input))
-    return Err;
-
-  // Create a work list that consist of the map triple/output file.
-  StringMap<StringRef> Worklist;
-  auto Output = OutputFileNames.begin();
-  for (auto &Triple : TargetNames) {
-    Worklist[Triple] = *Output;
-    ++Output;
-  }
-
-  // Read all the bundles that are in the work list. If we find no bundles we
-  // assume the file is meant for the host target.
-  bool FoundHostBundle = false;
-  while (!Worklist.empty()) {
-    Expected<Optional<StringRef>> CurTripleOrErr = FH->ReadBundleStart(Input);
-    if (!CurTripleOrErr)
-      return CurTripleOrErr.takeError();
-
-    // We don't have more bundles.
-    if (!*CurTripleOrErr)
-      break;
-
-    StringRef CurTriple = **CurTripleOrErr;
-    assert(!CurTriple.empty());
-
-    auto Output = Worklist.find(CurTriple);
-    // The file may have more bundles for other targets, that we don't care
-    // about. Therefore, move on to the next triple
-    if (Output == Worklist.end())
-      continue;
-
-    // Check if the output file can be opened and copy the bundle to it.
-    std::error_code EC;
-    raw_fd_ostream OutputFile(Output->second, EC, sys::fs::OF_None);
-    if (EC)
-      return createFileError(Output->second, EC);
-    if (Error Err = FH->ReadBundle(OutputFile, Input))
-      return Err;
-    if (Error Err = FH->ReadBundleEnd(Input))
-      return Err;
-    Worklist.erase(Output);
-
-    // Record if we found the host bundle.
-    auto OffloadInfo = OffloadTargetInfo(CurTriple);
-    if (OffloadInfo.hasHostKind())
-      FoundHostBundle = true;
-  }
-
-  if (!AllowMissingBundles && !Worklist.empty()) {
-    std::string ErrMsg = "Can't find bundles for";
-    std::set<StringRef> Sorted;
-    for (auto &E : Worklist)
-      Sorted.insert(E.first());
-    unsigned I = 0;
-    unsigned Last = Sorted.size() - 1;
-    for (auto &E : Sorted) {
-      if (I != 0 && Last > 1)
-        ErrMsg += ",";
-      ErrMsg += " ";
-      if (I == Last && I != 0)
-        ErrMsg += "and ";
-      ErrMsg += E.str();
-      ++I;
-    }
-    return createStringError(inconvertibleErrorCode(), ErrMsg);
-  }
-
-  // If no bundles were found, assume the input file is the host bundle and
-  // create empty files for the remaining targets.
-  if (Worklist.size() == TargetNames.size()) {
-    for (auto &E : Worklist) {
-      std::error_code EC;
-      raw_fd_ostream OutputFile(E.second, EC, sys::fs::OF_None);
-      if (EC)
-        return createFileError(E.second, EC);
-
-      // If this entry has a host kind, copy the input file to the output file.
-      auto OffloadInfo = OffloadTargetInfo(E.getKey());
-      if (OffloadInfo.hasHostKind())
-        OutputFile.write(Input.getBufferStart(), Input.getBufferSize());
-    }
-    return Error::success();
-  }
-
-  // If we found elements, we emit an error if none of those were for the host
-  // in case host bundle name was provided in command line.
-  if (!FoundHostBundle && HostInputIndex != ~0u)
-    return createStringError(inconvertibleErrorCode(),
-                             "Can't find bundle for the host target");
-
-  // If we still have any elements in the worklist, create empty files for them.
-  for (auto &E : Worklist) {
-    std::error_code EC;
-    raw_fd_ostream OutputFile(E.second, EC, sys::fs::OF_None);
-    if (EC)
-      return createFileError(E.second, EC);
-  }
-
-  return Error::success();
-}
-
-static Archive::Kind getDefaultArchiveKindForHost() {
-  return Triple(sys::getDefaultTargetTriple()).isOSDarwin() ? Archive::K_DARWIN
-                                                            : Archive::K_GNU;
-}
-
-/// @brief Checks if a code object \p CodeObjectInfo is compatible with a given
-/// target \p TargetInfo.
-/// @link https://clang.llvm.org/docs/ClangOffloadBundler.html#bundle-entry-id
-bool isCodeObjectCompatible(OffloadTargetInfo &CodeObjectInfo,
-                            OffloadTargetInfo &TargetInfo) {
-
-  // Compatible in case of exact match.
-  if (CodeObjectInfo == TargetInfo) {
-    DEBUG_WITH_TYPE("CodeObjectCompatibility",
-                    dbgs() << "Compatible: Exact match: \t[CodeObject: "
-                           << CodeObjectInfo.str()
-                           << "]\t:\t[Target: " << TargetInfo.str() << "]\n");
-    return true;
-  }
-
-  // Incompatible if Kinds or Triples mismatch.
-  if (!CodeObjectInfo.isOffloadKindCompatible(TargetInfo.OffloadKind) ||
-      !CodeObjectInfo.Triple.isCompatibleWith(TargetInfo.Triple)) {
-    DEBUG_WITH_TYPE(
-        "CodeObjectCompatibility",
-        dbgs() << "Incompatible: Kind/Triple mismatch \t[CodeObject: "
-               << CodeObjectInfo.str() << "]\t:\t[Target: " << TargetInfo.str()
-               << "]\n");
-    return false;
-  }
-
-  // Incompatible if GPUArch mismatch.
-  if (CodeObjectInfo.GPUArch != TargetInfo.GPUArch) {
-    DEBUG_WITH_TYPE("CodeObjectCompatibility",
-                    dbgs() << "Incompatible: GPU Arch mismatch \t[CodeObject: "
-                           << CodeObjectInfo.str()
-                           << "]\t:\t[Target: " << TargetInfo.str() << "]\n");
-    return false;
-  }
-
-  DEBUG_WITH_TYPE(
-      "CodeObjectCompatibility",
-      dbgs() << "Compatible: Code Objects are compatible \t[CodeObject: "
-             << CodeObjectInfo.str() << "]\t:\t[Target: " << TargetInfo.str()
-             << "]\n");
-  return true;
-}
-
-/// @brief Computes a list of targets among all given targets which are
-/// compatible with this code object
-/// @param [in] CodeObjectInfo Code Object
-/// @param [out] CompatibleTargets List of all compatible targets among all
-/// given targets
-/// @return false, if no compatible target is found.
-static bool
-getCompatibleOffloadTargets(OffloadTargetInfo &CodeObjectInfo,
-                            SmallVectorImpl<StringRef> &CompatibleTargets) {
-  if (!CompatibleTargets.empty()) {
-    DEBUG_WITH_TYPE("CodeObjectCompatibility",
-                    dbgs() << "CompatibleTargets list should be empty\n");
-    return false;
-  }
-  for (auto &Target : TargetNames) {
-    auto TargetInfo = OffloadTargetInfo(Target);
-    if (isCodeObjectCompatible(CodeObjectInfo, TargetInfo))
-      CompatibleTargets.push_back(Target);
-  }
-  return !CompatibleTargets.empty();
-}
-
-/// UnbundleArchive takes an archive file (".a") as input containing bundled
-/// code object files, and a list of offload targets (not host), and extracts
-/// the code objects into a new archive file for each offload target. Each
-/// resulting archive file contains all code object files corresponding to that
-/// particular offload target. The created archive file does not
-/// contain an index of the symbols and code object files are named as
-/// <<Parent Bundle Name>-<CodeObject's GPUArch>>, with ':' replaced with '_'.
-static Error UnbundleArchive() {
-  std::vector<std::unique_ptr<MemoryBuffer>> ArchiveBuffers;
-
-  /// Map of target names with list of object files that will form the device
-  /// specific archive for that target
-  StringMap<std::vector<NewArchiveMember>> OutputArchivesMap;
-
-  // Map of target names and output archive filenames
-  StringMap<StringRef> TargetOutputFileNameMap;
-
-  auto Output = OutputFileNames.begin();
-  for (auto &Target : TargetNames) {
-    TargetOutputFileNameMap[Target] = *Output;
-    ++Output;
-  }
-
-  StringRef IFName = InputFileNames.front();
-  ErrorOr<std::unique_ptr<MemoryBuffer>> BufOrErr =
-      MemoryBuffer::getFileOrSTDIN(IFName, true, false);
-  if (std::error_code EC = BufOrErr.getError())
-    return createFileError(InputFileNames.front(), EC);
-
-  ArchiveBuffers.push_back(std::move(*BufOrErr));
-  Expected<std::unique_ptr<llvm::object::Archive>> LibOrErr =
-      Archive::create(ArchiveBuffers.back()->getMemBufferRef());
-  if (!LibOrErr)
-    return LibOrErr.takeError();
-
-  auto Archive = std::move(*LibOrErr);
-
-  Error ArchiveErr = Error::success();
-  auto ChildEnd = Archive->child_end();
-
-  /// Iterate over all bundled code object files in the input archive.
-  for (auto ArchiveIter = Archive->child_begin(ArchiveErr);
-       ArchiveIter != ChildEnd; ++ArchiveIter) {
-    if (ArchiveErr)
-      return ArchiveErr;
-    auto ArchiveChildNameOrErr = (*ArchiveIter).getName();
-    if (!ArchiveChildNameOrErr)
-      return ArchiveChildNameOrErr.takeError();
-
-    StringRef BundledObjectFile = sys::path::filename(*ArchiveChildNameOrErr);
-
-    auto CodeObjectBufferRefOrErr = (*ArchiveIter).getMemoryBufferRef();
-    if (!CodeObjectBufferRefOrErr)
-      return CodeObjectBufferRefOrErr.takeError();
-
-    auto CodeObjectBuffer =
-        MemoryBuffer::getMemBuffer(*CodeObjectBufferRefOrErr, false);
-
-    Expected<std::unique_ptr<FileHandler>> FileHandlerOrErr =
-        CreateFileHandler(*CodeObjectBuffer);
-    if (!FileHandlerOrErr)
-      return FileHandlerOrErr.takeError();
-
-    std::unique_ptr<FileHandler> &FileHandler = *FileHandlerOrErr;
-    assert(FileHandler &&
-           "FileHandle creation failed for file in the archive!");
-
-    if (Error ReadErr = FileHandler.get()->ReadHeader(*CodeObjectBuffer))
-      return ReadErr;
-
-    Expected<Optional<StringRef>> CurBundleIDOrErr =
-        FileHandler->ReadBundleStart(*CodeObjectBuffer);
-    if (!CurBundleIDOrErr)
-      return CurBundleIDOrErr.takeError();
-
-    Optional<StringRef> OptionalCurBundleID = *CurBundleIDOrErr;
-    // No device code in this child, skip.
-    if (!OptionalCurBundleID)
-      continue;
-    StringRef CodeObject = *OptionalCurBundleID;
-
-    // Process all bundle entries (CodeObjects) found in this child of input
-    // archive.
-    while (!CodeObject.empty()) {
-      SmallVector<StringRef> CompatibleTargets;
-      auto CodeObjectInfo = OffloadTargetInfo(CodeObject);
-      if (CodeObjectInfo.hasHostKind()) {
-        // Do nothing, we don't extract host code yet.
-      } else if (getCompatibleOffloadTargets(CodeObjectInfo,
-                                             CompatibleTargets)) {
-        std::string BundleData;
-        raw_string_ostream DataStream(BundleData);
-        if (Error Err =
-                FileHandler.get()->ReadBundle(DataStream, *CodeObjectBuffer))
-          return Err;
-
-        for (auto &CompatibleTarget : CompatibleTargets) {
-          SmallString<128> BundledObjectFileName;
-          BundledObjectFileName.assign(BundledObjectFile);
-          auto OutputBundleName =
-              Twine(llvm::sys::path::stem(BundledObjectFileName) + "-" +
-                    CodeObject +
-                    getDeviceLibraryFileName(BundledObjectFileName,
-                                             CodeObjectInfo.GPUArch))
-                  .str();
-          // Replace ':' in optional target feature list with '_' to ensure
-          // cross-platform validity.
-          std::replace(OutputBundleName.begin(), OutputBundleName.end(), ':',
-                       '_');
-
-          std::unique_ptr<MemoryBuffer> MemBuf = MemoryBuffer::getMemBufferCopy(
-              DataStream.str(), OutputBundleName);
-          ArchiveBuffers.push_back(std::move(MemBuf));
-          llvm::MemoryBufferRef MemBufRef =
-              MemoryBufferRef(*(ArchiveBuffers.back()));
-
-          // For inserting <CompatibleTarget, list<CodeObject>> entry in
-          // OutputArchivesMap.
-          if (OutputArchivesMap.find(CompatibleTarget) ==
-              OutputArchivesMap.end()) {
-
-            std::vector<NewArchiveMember> ArchiveMembers;
-            ArchiveMembers.push_back(NewArchiveMember(MemBufRef));
-            OutputArchivesMap.insert_or_assign(CompatibleTarget,
-                                               std::move(ArchiveMembers));
-          } else {
-            OutputArchivesMap[CompatibleTarget].push_back(
-                NewArchiveMember(MemBufRef));
-          }
-        }
-      }
-
-      if (Error Err = FileHandler.get()->ReadBundleEnd(*CodeObjectBuffer))
-        return Err;
-
-      Expected<Optional<StringRef>> NextTripleOrErr =
-          FileHandler->ReadBundleStart(*CodeObjectBuffer);
-      if (!NextTripleOrErr)
-        return NextTripleOrErr.takeError();
-
-      CodeObject = NextTripleOrErr->value_or("");
-    } // End of processing of all bundle entries of this child of input archive.
-  }   // End of while over children of input archive.
-
-  assert(!ArchiveErr && "Error occurred while reading archive!");
-
-  /// Write out an archive for each target
-  for (auto &Target : TargetNames) {
-    StringRef FileName = TargetOutputFileNameMap[Target];
-    StringMapIterator<std::vector<llvm::NewArchiveMember>> CurArchiveMembers =
-        OutputArchivesMap.find(Target);
-    if (CurArchiveMembers != OutputArchivesMap.end()) {
-      if (Error WriteErr = writeArchive(FileName, CurArchiveMembers->getValue(),
-                                        true, getDefaultArchiveKindForHost(),
-                                        true, false, nullptr))
-        return WriteErr;
-    } else if (!AllowMissingBundles) {
-      std::string ErrMsg =
-          Twine("no compatible code object found for the target '" + Target +
-                "' in heterogeneous archive library: " + IFName)
-              .str();
-      return createStringError(inconvertibleErrorCode(), ErrMsg);
-    } else { // Create an empty archive file if no compatible code object is
-             // found and "allow-missing-bundles" is enabled. It ensures that
-             // the linker using output of this step doesn't complain about
-             // the missing input file.
-      std::vector<llvm::NewArchiveMember> EmptyArchive;
-      EmptyArchive.clear();
-      if (Error WriteErr = writeArchive(FileName, EmptyArchive, true,
-                                        getDefaultArchiveKindForHost(), true,
-                                        false, nullptr))
-        return WriteErr;
-    }
-  }
-
-  return Error::success();
-}
+std::string BundlerExecutable;
 
 static void PrintVersion(raw_ostream &OS) {
   OS << clang::getClangToolFullVersion("clang-offload-bundler") << '\n';
 }
 
 int main(int argc, const char **argv) {
   sys::PrintStackTraceOnErrorSignal(argv[0]);
 
int main(int argc, const char **argv) {
   };
 
   if (InputFileNames.getNumOccurrences() != 0 &&
       InputFileNamesDeprecatedOpt.getNumOccurrences() != 0) {
     reportError(createStringError(
         errc::invalid_argument,
         "-inputs and -input cannot be used together, use only -input instead"));
   }
+
   if (InputFileNamesDeprecatedOpt.size()) {
     warningOS() << "-inputs is deprecated, use -input instead\n";
     // temporary hack to support -inputs
     std::vector<std::string> &s = InputFileNames;
     s.insert(s.end(), InputFileNamesDeprecatedOpt.begin(),
              InputFileNamesDeprecatedOpt.end());
   }
 
   if (OutputFileNames.getNumOccurrences() != 0 &&
       OutputFileNamesDeprecatedOpt.getNumOccurrences() != 0) {
     reportError(createStringError(errc::invalid_argument,
                                   "-outputs and -output cannot be used "
                                   "together, use only -output instead"));
   }
+
   if (OutputFileNamesDeprecatedOpt.size()) {
     warningOS() << "-outputs is deprecated, use -output instead\n";
     // temporary hack to support -outputs
     std::vector<std::string> &s = OutputFileNames;
     s.insert(s.end(), OutputFileNamesDeprecatedOpt.begin(),
              OutputFileNamesDeprecatedOpt.end());
   }
 
if (ListBundleIDs) {
     doWork([]() { return ListBundleIDsInFile(InputFileNames.front()); });
     return 0;
   }
 
   if (OutputFileNames.size() == 0) {
     reportError(
         createStringError(errc::invalid_argument, "no output file specified!"));
   }
+
   if (TargetNames.getNumOccurrences() == 0) {
     reportError(createStringError(
         errc::invalid_argument,
         "for the --targets option: must be specified at least once!"));
   }
+
   if (Unbundle) {
     if (InputFileNames.size() != 1) {
       reportError(createStringError(
           errc::invalid_argument,
           "only one input file supported in unbundling mode"));
     }
     if (OutputFileNames.size() != TargetNames.size()) {
       reportError(createStringError(errc::invalid_argument,

clang/tools/clang-offload-bundler/OffloadBundler.h

+//===-- clang-offload-bundler/OffloadBundler.h ----------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+///
+/// \file
+/// This file defines a clang-offload-bundler library that bundles different
+/// files that relate with the same source code but different targets into a
+/// single one. Also the implements the opposite functionality, i.e. unbundle
+/// files previous created by this tool.
+///
+//===----------------------------------------------------------------------===//
+
+using namespace llvm;
+using namespace llvm::object;
+
+Error BundleFiles();
+Error UnbundleFiles();
+Error UnbundleArchive();
+
+/// Obtain the offload kind, real machine triple, and an optional GPUArch
+/// out of the target information specified by the user.
+/// Bundle Entry ID (or, Offload Target String) has following components:
+///  * Offload Kind - Host, OpenMP, or HIP
+///  * Triple - Standard LLVM Triple
+///  * GPUArch (Optional) - Processor name, followed by set of ON/OFF features
+struct OffloadTargetInfo {
+  StringRef OffloadKind;
+  llvm::Triple Triple;
+  StringRef GPUArch;
+
+  OffloadTargetInfo(const StringRef Target);
+  bool hasHostKind() const;
+  bool isOffloadKindValid() const;
+  bool isOffloadKindCompatible(const StringRef TargetOffloadKind) const;
+  bool isTripleValid() const;
+  bool operator==(const OffloadTargetInfo &Target) const;
+  std::string str();
+};
+
+// List bundle IDs. Return true if an error was found.
+Error ListBundleIDsInFile(StringRef InputFileName);

clang/tools/clang-offload-bundler/OffloadBundler.cpp

 //===-- clang-offload-bundler/ClangOffloadBundler.cpp ---------------------===//
 //
 // 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 <cstdint>
 #include <forward_list>
 #include <memory>
 #include <set>
 #include <string>
 #include <system_error>
 #include <utility>
 
+#include "OffloadBundler.h"
+
 using namespace llvm;
 using namespace llvm::object;
 
-static cl::opt<bool> Help("h", cl::desc("Alias for -help"), cl::Hidden);
-
-// Mark all our options with this category, everything else (except for -version
-// and -help) will be hidden.
-static cl::OptionCategory
-    ClangOffloadBundlerCategory("clang-offload-bundler options");
-static cl::list<std::string>
-    InputFileNames("input",
-                   cl::desc("Input file."
-                            " Can be specified multiple times "
-                            "for multiple input files."),
-                   cl::cat(ClangOffloadBundlerCategory));
-static cl::list<std::string>
-    InputFileNamesDeprecatedOpt("inputs", cl::CommaSeparated,
-                                cl::desc("[<input file>,...] (deprecated)"),
-                                cl::cat(ClangOffloadBundlerCategory));
-static cl::list<std::string>
-    OutputFileNames("output",
-                    cl::desc("Output file."
-                             " Can be specified multiple times "
-                             "for multiple output files."),
-                    cl::cat(ClangOffloadBundlerCategory));
-static cl::list<std::string>
-    OutputFileNamesDeprecatedOpt("outputs", cl::CommaSeparated,
-                                 cl::desc("[<output file>,...] (deprecated)"),
-                                 cl::cat(ClangOffloadBundlerCategory));
-static cl::list<std::string>
-    TargetNames("targets", cl::CommaSeparated,
-                cl::desc("[<offload kind>-<target triple>,...]"),
-                cl::cat(ClangOffloadBundlerCategory));
-static cl::opt<std::string>
-    FilesType("type", cl::Required,
-              cl::desc("Type of the files to be bundled/unbundled.\n"
-                       "Current supported types are:\n"
-                       "  i   - cpp-output\n"
-                       "  ii  - c++-cpp-output\n"
-                       "  cui - cuda/hip-output\n"
-                       "  d   - dependency\n"
-                       "  ll  - llvm\n"
-                       "  bc  - llvm-bc\n"
-                       "  s   - assembler\n"
-                       "  o   - object\n"
-                       "  a   - archive of objects\n"
-                       "  gch - precompiled-header\n"
-                       "  ast - clang AST file"),
-              cl::cat(ClangOffloadBundlerCategory));
-static cl::opt<bool>
-    Unbundle("unbundle",
-             cl::desc("Unbundle bundled file into several output files.\n"),
-             cl::init(false), cl::cat(ClangOffloadBundlerCategory));
-
-static cl::opt<bool>
-    ListBundleIDs("list", cl::desc("List bundle IDs in the bundled file.\n"),
-                  cl::init(false), cl::cat(ClangOffloadBundlerCategory));
-
-static cl::opt<bool> PrintExternalCommands(
-    "###",
-    cl::desc("Print any external commands that are to be executed "
-             "instead of actually executing them - for testing purposes.\n"),
-    cl::init(false), cl::cat(ClangOffloadBundlerCategory));
-
-static cl::opt<bool>
-    AllowMissingBundles("allow-missing-bundles",
-                        cl::desc("Create empty files if bundles are missing "
-                                 "when unbundling.\n"),
-                        cl::init(false), cl::cat(ClangOffloadBundlerCategory));
-
-static cl::opt<unsigned>
-    BundleAlignment("bundle-align",
-                    cl::desc("Alignment of bundle for binary files"),
-                    cl::init(1), cl::cat(ClangOffloadBundlerCategory));
-
-static cl::opt<bool> HipOpenmpCompatible(
-    "hip-openmp-compatible",
-    cl::desc("Treat hip and hipv4 offload kinds as "
-             "compatible with openmp kind, and vice versa.\n"),
-    cl::init(false), cl::cat(ClangOffloadBundlerCategory));
+extern cl::list<std::string> InputFileNames;
+extern cl::list<std::string> OutputFileNames;
+extern cl::list<std::string> TargetNames;
+extern cl::opt<std::string> FilesType;
+extern cl::opt<bool> PrintExternalCommands;
+extern cl::opt<bool> AllowMissingBundles;
+extern cl::opt<unsigned> BundleAlignment;
+extern cl::opt<bool> HipOpenmpCompatible;
 
 /// Magic string that marks the existence of offloading data.
 #define OFFLOAD_BUNDLER_MAGIC_STR "__CLANG_OFFLOAD_BUNDLE__"
 
 /// The index of the host input in the list of inputs.
-static unsigned HostInputIndex = ~0u;
+extern unsigned HostInputIndex;
 
 /// Whether not having host target is allowed.
-static bool AllowNoHost = false;
+extern bool AllowNoHost;
 
 /// Path to the current binary.
-static std::string BundlerExecutable;
-
-/// Obtain the offload kind, real machine triple, and an optional GPUArch
-/// out of the target information specified by the user.
-/// Bundle Entry ID (or, Offload Target String) has following components:
-///  * Offload Kind - Host, OpenMP, or HIP
-///  * Triple - Standard LLVM Triple
-///  * GPUArch (Optional) - Processor name, like gfx906 or sm_30
-
-struct OffloadTargetInfo {
-  StringRef OffloadKind;
-  llvm::Triple Triple;
-  StringRef GPUArch;
+extern std::string BundlerExecutable;
 
-  OffloadTargetInfo(const StringRef Target) {
-    auto TargetFeatures = Target.split(':');
-    auto TripleOrGPU = TargetFeatures.first.rsplit('-');
+OffloadTargetInfo::OffloadTargetInfo(const StringRef Target) {
 
-    if (clang::StringToCudaArch(TripleOrGPU.second) !=
-        clang::CudaArch::UNKNOWN) {
-      auto KindTriple = TripleOrGPU.first.split('-');
-      this->OffloadKind = KindTriple.first;
-      this->Triple = llvm::Triple(KindTriple.second);
-      this->GPUArch = Target.substr(Target.find(TripleOrGPU.second));
-    } else {
-      auto KindTriple = TargetFeatures.first.split('-');
-      this->OffloadKind = KindTriple.first;
-      this->Triple = llvm::Triple(KindTriple.second);
-      this->GPUArch = "";
-    }
-  }
+    this->GPUArch= "";
 
-  bool hasHostKind() const { return this->OffloadKind == "host"; }
+bool OffloadTargetInfo::hasHostKind() const { return this->OffloadKind == "host"; }
 
-  bool isOffloadKindValid() const {
-    return OffloadKind == "host" || OffloadKind == "openmp" ||
-           OffloadKind == "hip" || OffloadKind == "hipv4";
-  }
+bool OffloadTargetInfo::isOffloadKindValid() const {
 
-  bool isOffloadKindCompatible(const StringRef TargetOffloadKind) const {
-    if (OffloadKind == TargetOffloadKind)
-      return true;
-    if (HipOpenmpCompatible) {
-      bool HIPCompatibleWithOpenMP =
-          OffloadKind.startswith_insensitive("hip") &&
-          TargetOffloadKind == "openmp";
-      bool OpenMPCompatibleWithHIP =
-          OffloadKind == "openmp" &&
-          TargetOffloadKind.startswith_insensitive("hip");
-      return HIPCompatibleWithOpenMP || OpenMPCompatibleWithHIP;
-    }
-    return false;
-  }
+bool OffloadTargetInfo::isOffloadKindCompatible(const StringRef TargetOffloadKind) const {
 
-  bool isTripleValid() const {
-    return !Triple.str().empty() && Triple.getArch() != Triple::UnknownArch;
-  }
+bool OffloadTargetInfo::isTripleValid() const {
 
-  bool operator==(const OffloadTargetInfo &Target) const {
-    return OffloadKind == Target.OffloadKind &&
-           Triple.isCompatibleWith(Target.Triple) && GPUArch == Target.GPUArch;
-  }
+bool OffloadTargetInfo::operator==(const OffloadTargetInfo &Target) const {
 
-  std::string str() {
-    return Twine(OffloadKind + "-" + Triple.str() + "-" + GPUArch).str();
-  }
-};
+std::string OffloadTargetInfo::str() {
 
 static StringRef getDeviceFileExtension(StringRef Device,
                                         StringRef BundleFileName) {
   if (Device.contains("gfx"))
     return ".bc";
   if (Device.contains("sm_"))
     return ".cubin";
   return sys::path::extension(BundleFileName);
public:
 
   /// Write the bundle from \a Input into \a OS.
   virtual Error WriteBundle(raw_fd_ostream &OS, MemoryBuffer &Input) = 0;
 
   /// List bundle IDs in \a Input.
   virtual Error listBundleIDs(MemoryBuffer &Input) {
     if (Error Err = ReadHeader(Input))
       return Err;
-
     return forEachBundle(Input, [&](const BundleInfo &Info) -> Error {
       llvm::outs() << Info.BundleID << '\n';
       Error Err = listBundleIDsCallback(Input, Info);
       if (Err)
         return Err;
       return Error::success();
     });
   }
if (FilesType == "gch")
     return std::make_unique<BinaryFileHandler>();
   if (FilesType == "ast")
     return std::make_unique<BinaryFileHandler>();
 
   return createStringError(errc::invalid_argument,
                            "'" + FilesType + "': invalid file type specified");
 }
 
+// List bundle IDs. Return true if an error was found.
+Error ListBundleIDsInFile(StringRef InputFileName) {
+  // Open Input file.
+  ErrorOr<std::unique_ptr<MemoryBuffer>> CodeOrErr =
+      MemoryBuffer::getFileOrSTDIN(InputFileName);
+  if (std::error_code EC = CodeOrErr.getError())
+    return createFileError(InputFileName, EC);
+
+  MemoryBuffer &Input = **CodeOrErr;
+
+  // Select the right files handler.
+  Expected<std::unique_ptr<FileHandler>> FileHandlerOrErr =
+      CreateFileHandler(Input);
+  if (!FileHandlerOrErr)
+    return FileHandlerOrErr.takeError();
+
+  std::unique_ptr<FileHandler> &FH = *FileHandlerOrErr;
+  assert(FH);
+  return FH->listBundleIDs(Input);
+}
+
 /// Bundle the files. Return true if an error was found.
-static Error BundleFiles() {
+Error BundleFiles() {
   std::error_code EC;
 
   // Create output file.
   raw_fd_ostream OutputFile(OutputFileNames.front(), EC, sys::fs::OF_None);
   if (EC)
     return createFileError(OutputFileNames.front(), EC);
 
   // Open input files.
if (Error Err = FH->WriteBundle(OutputFile, **Input))
       return Err;
     if (Error Err = FH->WriteBundleEnd(OutputFile, Triple))
       return Err;
     ++Input;
   }
   return Error::success();
 }
 
-// List bundle IDs. Return true if an error was found.
-static Error ListBundleIDsInFile(StringRef InputFileName) {
-  // Open Input file.
-  ErrorOr<std::unique_ptr<MemoryBuffer>> CodeOrErr =
-      MemoryBuffer::getFileOrSTDIN(InputFileName);
-  if (std::error_code EC = CodeOrErr.getError())
-    return createFileError(InputFileName, EC);
-
-  MemoryBuffer &Input = **CodeOrErr;
-
-  // Select the right files handler.
-  Expected<std::unique_ptr<FileHandler>> FileHandlerOrErr =
-      CreateFileHandler(Input);
-  if (!FileHandlerOrErr)
-    return FileHandlerOrErr.takeError();
-
-  std::unique_ptr<FileHandler> &FH = *FileHandlerOrErr;
-  assert(FH);
-  return FH->listBundleIDs(Input);
-}
-
 // Unbundle the files. Return true if an error was found.
-static Error UnbundleFiles() {
+Error UnbundleFiles() {
   // Open Input file.
   ErrorOr<std::unique_ptr<MemoryBuffer>> CodeOrErr =
       MemoryBuffer::getFileOrSTDIN(InputFileNames.front());
   if (std::error_code EC = CodeOrErr.getError())
     return createFileError(InputFileNames.front(), EC);
 
   MemoryBuffer &Input = **CodeOrErr;
 

 
 /// UnbundleArchive takes an archive file (".a") as input containing bundled
 /// code object files, and a list of offload targets (not host), and extracts
 /// the code objects into a new archive file for each offload target. Each
 /// resulting archive file contains all code object files corresponding to that
 /// particular offload target. The created archive file does not
 /// contain an index of the symbols and code object files are named as
 /// <<Parent Bundle Name>-<CodeObject's GPUArch>>, with ':' replaced with '_'.
-static Error UnbundleArchive() {
+Error UnbundleArchive() {
   std::vector<std::unique_ptr<MemoryBuffer>> ArchiveBuffers;
 
   /// Map of target names with list of object files that will form the device
   /// specific archive for that target
   StringMap<std::vector<NewArchiveMember>> OutputArchivesMap;
 
   // Map of target names and output archive filenames
   StringMap<StringRef> TargetOutputFileNameMap;
 
   auto Output = OutputFileNames.begin();
   for (auto &Target : TargetNames) {
     TargetOutputFileNameMap[Target] = *Output;
     ++Output;
   }
 
   StringRef IFName = InputFileNames.front();
+
   ErrorOr<std::unique_ptr<MemoryBuffer>> BufOrErr =
       MemoryBuffer::getFileOrSTDIN(IFName, true, false);
   if (std::error_code EC = BufOrErr.getError())
     return createFileError(InputFileNames.front(), EC);
 
   ArchiveBuffers.push_back(std::move(*BufOrErr));
   Expected<std::unique_ptr<llvm::object::Archive>> LibOrErr =
       Archive::create(ArchiveBuffers.back()->getMemBufferRef());
for (auto ArchiveIter = Archive->child_begin(ArchiveErr);
 
     Expected<std::unique_ptr<FileHandler>> FileHandlerOrErr =
         CreateFileHandler(*CodeObjectBuffer);
     if (!FileHandlerOrErr)
       return FileHandlerOrErr.takeError();
 
     std::unique_ptr<FileHandler> &FileHandler = *FileHandlerOrErr;
     assert(FileHandler &&
-           "FileHandle creation failed for file in the archive!");
+     "FileHandle creation failed for file in the archive!");
 
     if (Error ReadErr = FileHandler.get()->ReadHeader(*CodeObjectBuffer))
       return ReadErr;
 
     Expected<Optional<StringRef>> CurBundleIDOrErr =
         FileHandler->ReadBundleStart(*CodeObjectBuffer);
     if (!CurBundleIDOrErr)
       return CurBundleIDOrErr.takeError();
 
     Optional<StringRef> OptionalCurBundleID = *CurBundleIDOrErr;
     // No device code in this child, skip.
-    if (!OptionalCurBundleID)
+    if (!OptionalCurBundleID.hasValue())
       continue;
     StringRef CodeObject = *OptionalCurBundleID;
 
     // Process all bundle entries (CodeObjects) found in this child of input
     // archive.
     while (!CodeObject.empty()) {
       SmallVector<StringRef> CompatibleTargets;
       auto CodeObjectInfo = OffloadTargetInfo(CodeObject);
while (!CodeObject.empty()) {
       if (Error Err = FileHandler.get()->ReadBundleEnd(*CodeObjectBuffer))
         return Err;
 
       Expected<Optional<StringRef>> NextTripleOrErr =
           FileHandler->ReadBundleStart(*CodeObjectBuffer);
       if (!NextTripleOrErr)
         return NextTripleOrErr.takeError();
 
-      CodeObject = NextTripleOrErr->value_or("");
+      CodeObject = ((*NextTripleOrErr).hasValue()) ? **NextTripleOrErr : "";
     } // End of processing of all bundle entries of this child of input archive.
   }   // End of while over children of input archive.
 
   assert(!ArchiveErr && "Error occurred while reading archive!");
 
   /// Write out an archive for each target
   for (auto &Target : TargetNames) {
     StringRef FileName = TargetOutputFileNameMap[Target];
if (CurArchiveMembers != OutputArchivesMap.end()) {
                                         getDefaultArchiveKindForHost(), true,
                                         false, nullptr))
         return WriteErr;
     }
   }
 
   return Error::success();
 }
-
-static void PrintVersion(raw_ostream &OS) {
-  OS << clang::getClangToolFullVersion("clang-offload-bundler") << '\n';
-}
-
-int main(int argc, const char **argv) {
-  sys::PrintStackTraceOnErrorSignal(argv[0]);
-
-  cl::HideUnrelatedOptions(ClangOffloadBundlerCategory);
-  cl::SetVersionPrinter(PrintVersion);
-  cl::ParseCommandLineOptions(
-      argc, argv,
-      "A tool to bundle several input files of the specified type <type> \n"
-      "referring to the same source file but different targets into a single \n"
-      "one. The resulting file can also be unbundled into different files by \n"
-      "this tool if -unbundle is provided.\n");
-
-  if (Help) {
-    cl::PrintHelpMessage();
-    return 0;
-  }
-
-  auto reportError = [argv](Error E) {
-    logAllUnhandledErrors(std::move(E), WithColor::error(errs(), argv[0]));
-    exit(1);
-  };
-
-  auto doWork = [&](std::function<llvm::Error()> Work) {
-    // Save the current executable directory as it will be useful to find other
-    // tools.
-    BundlerExecutable = argv[0];
-    if (!llvm::sys::fs::exists(BundlerExecutable))
-      BundlerExecutable =
-          sys::fs::getMainExecutable(argv[0], &BundlerExecutable);
-
-    if (llvm::Error Err = Work()) {
-      reportError(std::move(Err));
-    }
-  };
-
-  auto warningOS = [argv]() -> raw_ostream & {
-    return WithColor::warning(errs(), StringRef(argv[0]));
-  };
-
-  if (InputFileNames.getNumOccurrences() != 0 &&
-      InputFileNamesDeprecatedOpt.getNumOccurrences() != 0) {
-    reportError(createStringError(
-        errc::invalid_argument,
-        "-inputs and -input cannot be used together, use only -input instead"));
-  }
-  if (InputFileNamesDeprecatedOpt.size()) {
-    warningOS() << "-inputs is deprecated, use -input instead\n";
-    // temporary hack to support -inputs
-    std::vector<std::string> &s = InputFileNames;
-    s.insert(s.end(), InputFileNamesDeprecatedOpt.begin(),
-             InputFileNamesDeprecatedOpt.end());
-  }
-
-  if (OutputFileNames.getNumOccurrences() != 0 &&
-      OutputFileNamesDeprecatedOpt.getNumOccurrences() != 0) {
-    reportError(createStringError(errc::invalid_argument,
-                                  "-outputs and -output cannot be used "
-                                  "together, use only -output instead"));
-  }
-  if (OutputFileNamesDeprecatedOpt.size()) {
-    warningOS() << "-outputs is deprecated, use -output instead\n";
-    // temporary hack to support -outputs
-    std::vector<std::string> &s = OutputFileNames;
-    s.insert(s.end(), OutputFileNamesDeprecatedOpt.begin(),
-             OutputFileNamesDeprecatedOpt.end());
-  }
-
-  if (ListBundleIDs) {
-    if (Unbundle) {
-      reportError(
-          createStringError(errc::invalid_argument,
-                            "-unbundle and -list cannot be used together"));
-    }
-    if (InputFileNames.size() != 1) {
-      reportError(createStringError(errc::invalid_argument,
-                                    "only one input file supported for -list"));
-    }
-    if (OutputFileNames.size()) {
-      reportError(createStringError(errc::invalid_argument,
-                                    "-outputs option is invalid for -list"));
-    }
-    if (TargetNames.size()) {
-      reportError(createStringError(errc::invalid_argument,
-                                    "-targets option is invalid for -list"));
-    }
-
-    doWork([]() { return ListBundleIDsInFile(InputFileNames.front()); });
-    return 0;
-  }
-
-  if (OutputFileNames.size() == 0) {
-    reportError(
-        createStringError(errc::invalid_argument, "no output file specified!"));
-  }
-  if (TargetNames.getNumOccurrences() == 0) {
-    reportError(createStringError(
-        errc::invalid_argument,
-        "for the --targets option: must be specified at least once!"));
-  }
-  if (Unbundle) {
-    if (InputFileNames.size() != 1) {
-      reportError(createStringError(
-          errc::invalid_argument,
-          "only one input file supported in unbundling mode"));
-    }
-    if (OutputFileNames.size() != TargetNames.size()) {
-      reportError(createStringError(errc::invalid_argument,
-                                    "number of output files and targets should "
-                                    "match in unbundling mode"));
-    }
-  } else {
-    if (FilesType == "a") {
-      reportError(createStringError(errc::invalid_argument,
-                                    "Archive files are only supported "
-                                    "for unbundling"));
-    }
-    if (OutputFileNames.size() != 1) {
-      reportError(createStringError(
-          errc::invalid_argument,
-          "only one output file supported in bundling mode"));
-    }
-    if (InputFileNames.size() != TargetNames.size()) {
-      reportError(createStringError(
-          errc::invalid_argument,
-          "number of input files and targets should match in bundling mode"));
-    }
-  }
-
-  // Verify that the offload kinds and triples are known. We also check that we
-  // have exactly one host target.
-  unsigned Index = 0u;
-  unsigned HostTargetNum = 0u;
-  bool HIPOnly = true;
-  llvm::DenseSet<StringRef> ParsedTargets;
-  for (StringRef Target : TargetNames) {
-    if (ParsedTargets.contains(Target)) {
-      reportError(createStringError(errc::invalid_argument,
-                                    "Duplicate targets are not allowed"));
-    }
-    ParsedTargets.insert(Target);
-
-    auto OffloadInfo = OffloadTargetInfo(Target);
-    bool KindIsValid = OffloadInfo.isOffloadKindValid();
-    bool TripleIsValid = OffloadInfo.isTripleValid();
-
-    if (!KindIsValid || !TripleIsValid) {
-      SmallVector<char, 128u> Buf;
-      raw_svector_ostream Msg(Buf);
-      Msg << "invalid target '" << Target << "'";
-      if (!KindIsValid)
-        Msg << ", unknown offloading kind '" << OffloadInfo.OffloadKind << "'";
-      if (!TripleIsValid)
-        Msg << ", unknown target triple '" << OffloadInfo.Triple.str() << "'";
-      reportError(createStringError(errc::invalid_argument, Msg.str()));
-    }
-
-    if (KindIsValid && OffloadInfo.hasHostKind()) {
-      ++HostTargetNum;
-      // Save the index of the input that refers to the host.
-      HostInputIndex = Index;
-    }
-
-    if (OffloadInfo.OffloadKind != "hip" && OffloadInfo.OffloadKind != "hipv4")
-      HIPOnly = false;
-
-    ++Index;
-  }
-
-  // HIP uses clang-offload-bundler to bundle device-only compilation results
-  // for multiple GPU archs, therefore allow no host target if all entries
-  // are for HIP.
-  AllowNoHost = HIPOnly;
-
-  // Host triple is not really needed for unbundling operation, so do not
-  // treat missing host triple as error if we do unbundling.
-  if ((Unbundle && HostTargetNum > 1) ||
-      (!Unbundle && HostTargetNum != 1 && !AllowNoHost)) {
-    reportError(createStringError(errc::invalid_argument,
-                                  "expecting exactly one host target but got " +
-                                      Twine(HostTargetNum)));
-  }
-
-  doWork([]() {
-    if (Unbundle) {
-      if (FilesType == "a")
-        return UnbundleArchive();
-      else
-        return UnbundleFiles();
-    } else
-      return BundleFiles();
-  });
-  return 0;
-}