--- a/lld/MachO/Driver.h	Mon May 25 11:55:54 2020 +0900
+++ b/lld/MachO/Driver.h	Tue Jun 08 06:07:14 2021 +0900
@@ -10,15 +10,32 @@
 #define LLD_MACHO_DRIVER_H
 
 #include "lld/Common/LLVM.h"
+#include "llvm/ADT/Optional.h"
+#include "llvm/ADT/SetVector.h"
+#include "llvm/ADT/StringRef.h"
 #include "llvm/Option/OptTable.h"
+#include "llvm/Support/MemoryBuffer.h"
+
+#include <set>
+#include <type_traits>
+
+namespace llvm {
+namespace MachO {
+class InterfaceFile;
+} // namespace MachO
+} // namespace llvm
 
 namespace lld {
 namespace macho {
 
+class DylibFile;
+class InputFile;
+
 class MachOOptTable : public llvm::opt::OptTable {
 public:
   MachOOptTable();
   llvm::opt::InputArgList parse(ArrayRef<const char *> argv);
+  void printHelp(const char *argv0, bool showHidden) const;
 };
 
 // Create enum with OPT_xxx values for each option in Options.td
@@ -29,6 +46,81 @@
 #undef OPTION
 };
 
+void parseLCLinkerOption(InputFile *, unsigned argc, StringRef data);
+
+std::string createResponseFile(const llvm::opt::InputArgList &args);
+
+// Check for both libfoo.dylib and libfoo.tbd (in that order).
+llvm::Optional<std::string> resolveDylibPath(llvm::StringRef path);
+
+DylibFile *loadDylib(llvm::MemoryBufferRef mbref, DylibFile *umbrella = nullptr,
+                     bool isBundleLoader = false);
+
+// Search for all possible combinations of `{root}/{name}.{extension}`.
+// If \p extensions are not specified, then just search for `{root}/{name}`.
+llvm::Optional<llvm::StringRef>
+findPathCombination(const llvm::Twine &name,
+                    const std::vector<llvm::StringRef> &roots,
+                    ArrayRef<llvm::StringRef> extensions = {""});
+
+// If -syslibroot is specified, absolute paths to non-object files may be
+// rerooted.
+llvm::StringRef rerootPath(llvm::StringRef path);
+
+llvm::Optional<InputFile *> loadArchiveMember(MemoryBufferRef, uint32_t modTime,
+                                              StringRef archiveName,
+                                              bool objCOnly);
+
+uint32_t getModTime(llvm::StringRef path);
+
+void printArchiveMemberLoad(StringRef reason, const InputFile *);
+
+// Helper class to export dependency info.
+class DependencyTracker {
+public:
+  explicit DependencyTracker(llvm::StringRef path);
+
+  // Adds the given path to the set of not-found files.
+  inline void logFileNotFound(std::string path) {
+    if (active)
+      notFounds.insert(std::move(path));
+  }
+
+  inline void logFileNotFound(const Twine &path) {
+    if (active)
+      notFounds.insert(path.str());
+  }
+
+  // Writes the dependencies to specified path.
+  // The content is sorted by its Op Code, then within each section,
+  // alphabetical order.
+  void write(llvm::StringRef version,
+             const llvm::SetVector<InputFile *> &inputs,
+             llvm::StringRef output);
+
+private:
+  enum DepOpCode : uint8_t {
+    // Denotes the linker version.
+    Version = 0x00,
+    // Denotes the input files.
+    Input = 0x10,
+    // Denotes the files that do not exist(?)
+    NotFound = 0x11,
+    // Denotes the output files.
+    Output = 0x40,
+  };
+
+  const llvm::StringRef path;
+  bool active;
+
+  // The paths need to be alphabetically ordered.
+  // We need to own the paths because some of them are temporarily
+  // constructed.
+  std::set<std::string> notFounds;
+};
+
+extern DependencyTracker *depTracker;
+
 } // namespace macho
 } // namespace lld