[clang] [clang-tools-extra] [lld] [llvm] [llvm] Add subcommand support for OptTable (PR #155026)

[via llvm-commits]

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@@ -742,16 +746,62 @@ void OptTable::printHelp(raw_ostream &OS, const char *Usage, const char *Title,
 }
 
 void OptTable::internalPrintHelp(
-    raw_ostream &OS, const char *Usage, const char *Title, bool ShowHidden,
-    bool ShowAllAliases, std::function<bool(const Info &)> ExcludeOption,
+    raw_ostream &OS, const char *Usage, const char *Title, StringRef SubCommand,
+    bool ShowHidden, bool ShowAllAliases,
+    std::function<bool(const Info &)> ExcludeOption,
     Visibility VisibilityMask) const {
   OS << "OVERVIEW: " << Title << "\n\n";
-  OS << "USAGE: " << Usage << "\n\n";
 
   // Render help text into a map of group-name to a list of (option, help)
   // pairs.
   std::map<std::string, std::vector<OptionInfo>> GroupedOptionHelp;
 
+  typename ArrayRef<OptTable::SubCommand>::iterator ActiveSubCommand =
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PiJoules wrote:

Can probably use `auto` here also

https://github.com/llvm/llvm-project/pull/155026