[lld] [RFC] [LLD] [COFF] Restructure /debug: option handling, allow controlling features separately (PR #74820)

[Martin Storsjö via llvm-commits]

================
@@ -858,46 +858,6 @@ static std::string createResponseFile(const opt::InputArgList &args,
   return std::string(data.str());
 }
 
-enum class DebugKind {
-  Unknown,
-  None,
-  Full,
-  FastLink,
-  GHash,
-  NoGHash,
-  Dwarf,
-  Symtab
-};
-
-static DebugKind parseDebugKind(const opt::InputArgList &args) {
-  auto *a = args.getLastArg(OPT_debug, OPT_debug_opt);
-  if (!a)
-    return DebugKind::None;
-  if (a->getNumValues() == 0)
-    return DebugKind::Full;
-
-  DebugKind debug = StringSwitch<DebugKind>(a->getValue())
-                        .CaseLower("none", DebugKind::None)
-                        .CaseLower("full", DebugKind::Full)
-                        .CaseLower("fastlink", DebugKind::FastLink)
-                        // LLD extensions
-                        .CaseLower("ghash", DebugKind::GHash)
----------------
mstorsjo wrote:

@aganea I guess that sounds reasonable, although I'd prefer not to take on that kind of a change in behaviour as part of this patchset, it's tricky enough as it is (even if I guess it would make the code a bit simpler in some places) - I'd leave that to someone more familiar with PDB/ghash overall.

https://github.com/llvm/llvm-project/pull/74820