Make comments a little bit more clear.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@56463 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/utils/TableGen/LLVMCConfigurationEmitter.cpp b/utils/TableGen/LLVMCConfigurationEmitter.cpp
index 133415b..9bfb5da 100644
--- a/utils/TableGen/LLVMCConfigurationEmitter.cpp
+++ b/utils/TableGen/LLVMCConfigurationEmitter.cpp
@@ -826,8 +826,10 @@
     O << "InLangs.count(\"" << OptName << "\") != 0";
     return true;
   } else if (TestName == "in_language") {
-    // TODO: remove this restriction
-    // Works only for cmd_line!
+    // This works only for single-argument Tool::GenerateAction. Join
+    // tools can process several files in different languages simultaneously.
+
+    // TODO: make this work with Edge::Weight (if possible).
     O << "LangMap.GetLanguage(inFile) == \"" << OptName << '\"';
     return true;
   } else if (TestName == "not_empty") {