[clang] [flang] [llvm] [polly] [Plugins] Pass arguments to a pass plugin with -plugin-arg (PR #226773)

[Alexis Engelke via llvm-commits]

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@@ -47,3 +49,32 @@ Expected<PassPlugin> PassPlugin::Load(const std::string &Filename) {
 
   return P;
 }
+
+Error llvm::passPluginArguments(ArrayRef<PassPluginLibraryInfo> Infos,
+                                ArrayRef<std::string> Args) {
+  DenseMap<StringRef, unsigned> Index;
+  for (auto [I, Info] : enumerate(Infos))
+    Index[Info.PluginName] = I;
+  // The argument follows the first comma, so it is NUL-terminated.
+  SmallVector<SmallVector<const char *, 0>, 0> PluginArgs(Infos.size());
+  for (const std::string &Arg : Args) {
+    auto [Name, Rest] = StringRef(Arg).split(',');
+    if (!Rest.data())
+      return createStringError("expected <plugin>,<arg> in -plugin-arg=" + Arg);
+    auto It = Index.find(Name);
+    if (It == Index.end())
+      return createStringError("no pass plugin named '" + Name +
+                               "' is loaded, in -plugin-arg=" + Arg);
+    PluginArgs[It->second].push_back(Rest.data());
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aengelke wrote:

Please add a comment explaining why Rest is null-terminated. This seems rather sketchy but is unfortunately necessary due to cl::ParseCommandLineOptions API limitations...

https://github.com/llvm/llvm-project/pull/226773