diff --git a/clang/utils/TableGen/ClangOptionDocEmitter.cpp b/clang/utils/TableGen/ClangOptionDocEmitter.cpp
--- a/clang/utils/TableGen/ClangOptionDocEmitter.cpp
+++ b/clang/utils/TableGen/ClangOptionDocEmitter.cpp
@@ -238,6 +238,8 @@
   }
 }
 
+static StringRef DefaultMetaVarName = "<arg>";
+
 void emitOptionName(StringRef Prefix, const Record *Option, raw_ostream &OS) {
   // Find the arguments to list after the option.
   unsigned NumArgs = getNumArgsForKind(Option->getValueAsDef("Kind"), Option);
@@ -247,7 +249,7 @@
   if (HasMetaVarName)
     Args.push_back(std::string(Option->getValueAsString("MetaVarName")));
   else if (NumArgs == 1)
-    Args.push_back("<arg>");
+    Args.push_back(DefaultMetaVarName.str());
 
   // Fill up arguments if this option didn't provide a meta var name or it
   // supports an unlimited number of arguments. We can't see how many arguments
@@ -341,8 +343,33 @@
   OS << "\n\n";
 
   // Emit the description, if we have one.
+  const Record *R = Option.Option;
   std::string Description =
-      getRSTStringWithTextFallback(Option.Option, "DocBrief", "HelpText");
+      getRSTStringWithTextFallback(R, "DocBrief", "HelpText");
+
+  if (!isa<UnsetInit>(R->getValueInit("Values"))) {
+    if (!Description.empty() && Description.back() != '.')
+      Description.push_back('.');
+
+    StringRef MetaVarName;
+    if (!isa<UnsetInit>(R->getValueInit("MetaVarName")))
+      MetaVarName = R->getValueAsString("MetaVarName");
+    else
+      MetaVarName = DefaultMetaVarName;
+
+    SmallVector<StringRef> Values;
+    SplitString(R->getValueAsString("Values"), Values, ",");
+    Description += (" " + MetaVarName + " can be ").str();
+
+    if (Values.size() == 1) {
+      Description += ("'" + Values.front() + "'.").str();
+    } else {
+      Description += "one of '";
+      Description += join(Values.begin(), Values.end() - 1, "', '");
+      Description += ("' or '" + Values.back() + "'.").str();
+    }
+  }
+
   if (!Description.empty())
     OS << Description << "\n\n";
 }