+
+/// This function just prints the help message, exactly the same way as if the
+/// -help or -help-hidden option had been given on the command line.
+///
+/// NOTE: THIS FUNCTION TERMINATES THE PROGRAM!
+///
+/// \param Hidden if true will print hidden options
+/// \param Categorized if true print options in categories
+void PrintHelpMessage(bool Hidden = false, bool Categorized = false);
+
+//===----------------------------------------------------------------------===//
+// Public interface for accessing registered options.
+//
+
+/// \brief Use this to get a StringMap to all registered named options
+/// (e.g. -help). Note \p Map Should be an empty StringMap.
+///
+/// \return A reference to the StringMap used by the cl APIs to parse options.
+///
+/// Access to unnamed arguments (i.e. positional) are not provided because
+/// it is expected that the client already has access to these.
+///
+/// Typical usage:
+/// \code
+/// main(int argc,char* argv[]) {
+/// StringMap<llvm::cl::Option*> &opts = llvm::cl::getRegisteredOptions();
+/// assert(opts.count("help") == 1)
+/// opts["help"]->setDescription("Show alphabetical help information")
+/// // More code
+/// llvm::cl::ParseCommandLineOptions(argc,argv);
+/// //More code
+/// }
+/// \endcode
+///
+/// This interface is useful for modifying options in libraries that are out of
+/// the control of the client. The options should be modified before calling
+/// llvm::cl::ParseCommandLineOptions().
+///
+/// Hopefully this API can be depricated soon. Any situation where options need
+/// to be modified by tools or libraries should be handled by sane APIs rather
+/// than just handing around a global list.
+StringMap<Option *> &getRegisteredOptions();
+
+//===----------------------------------------------------------------------===//
+// Standalone command line processing utilities.
+//
+
+/// \brief Tokenizes a command line that can contain escapes and quotes.
+//
+/// The quoting rules match those used by GCC and other tools that use
+/// libiberty's buildargv() or expandargv() utilities, and do not match bash.
+/// They differ from buildargv() on treatment of backslashes that do not escape
+/// a special character to make it possible to accept most Windows file paths.
+///
+/// \param [in] Source The string to be split on whitespace with quotes.
+/// \param [in] Saver Delegates back to the caller for saving parsed strings.
+/// \param [in] MarkEOLs true if tokenizing a response file and you want end of
+/// lines and end of the response file to be marked with a nullptr string.
+/// \param [out] NewArgv All parsed strings are appended to NewArgv.
+void TokenizeGNUCommandLine(StringRef Source, StringSaver &Saver,
+ SmallVectorImpl<const char *> &NewArgv,
+ bool MarkEOLs = false);
+
+/// \brief Tokenizes a Windows command line which may contain quotes and escaped
+/// quotes.
+///
+/// See MSDN docs for CommandLineToArgvW for information on the quoting rules.
+/// http://msdn.microsoft.com/en-us/library/windows/desktop/17w5ykft(v=vs.85).aspx
+///
+/// \param [in] Source The string to be split on whitespace with quotes.
+/// \param [in] Saver Delegates back to the caller for saving parsed strings.
+/// \param [in] MarkEOLs true if tokenizing a response file and you want end of
+/// lines and end of the response file to be marked with a nullptr string.
+/// \param [out] NewArgv All parsed strings are appended to NewArgv.
+void TokenizeWindowsCommandLine(StringRef Source, StringSaver &Saver,
+ SmallVectorImpl<const char *> &NewArgv,
+ bool MarkEOLs = false);
+
+/// \brief String tokenization function type. Should be compatible with either
+/// Windows or Unix command line tokenizers.
+typedef void (*TokenizerCallback)(StringRef Source, StringSaver &Saver,
+ SmallVectorImpl<const char *> &NewArgv,
+ bool MarkEOLs);
+
+/// \brief Expand response files on a command line recursively using the given
+/// StringSaver and tokenization strategy. Argv should contain the command line
+/// before expansion and will be modified in place. If requested, Argv will
+/// also be populated with nullptrs indicating where each response file line
+/// ends, which is useful for the "/link" argument that needs to consume all
+/// remaining arguments only until the next end of line, when in a response
+/// file.
+///
+/// \param [in] Saver Delegates back to the caller for saving parsed strings.
+/// \param [in] Tokenizer Tokenization strategy. Typically Unix or Windows.
+/// \param [in,out] Argv Command line into which to expand response files.
+/// \param [in] MarkEOLs Mark end of lines and the end of the response file
+/// with nullptrs in the Argv vector.
+/// \return true if all @files were expanded successfully or there were none.
+bool ExpandResponseFiles(StringSaver &Saver, TokenizerCallback Tokenizer,
+ SmallVectorImpl<const char *> &Argv,
+ bool MarkEOLs = false);
+
+/// \brief Mark all options not part of this category as cl::ReallyHidden.
+///
+/// \param Category the category of options to keep displaying
+///
+/// Some tools (like clang-format) like to be able to hide all options that are
+/// not specific to the tool. This function allows a tool to specify a single
+/// option category to display in the -help output.
+void HideUnrelatedOptions(cl::OptionCategory &Category);
+
+/// \brief Mark all options not part of the categories as cl::ReallyHidden.
+///
+/// \param Categories the categories of options to keep displaying.
+///
+/// Some tools (like clang-format) like to be able to hide all options that are
+/// not specific to the tool. This function allows a tool to specify a single
+/// option category to display in the -help output.
+void HideUnrelatedOptions(ArrayRef<const cl::OptionCategory *> Categories);