diff --git a/llvm/utils/split-file/split-file.cpp b/llvm/utils/split-file/split-file.cpp
--- a/llvm/utils/split-file/split-file.cpp
+++ b/llvm/utils/split-file/split-file.cpp
@@ -43,6 +43,15 @@
                                     cl::desc("Don't preserve line numbers (default)"),
                                     cl::cat(cat));
 
+static cl::opt<std::string> addFileExtension("add-file-extension",
+                                             cl::desc("Add an extension to output file names"),
+                                             cl::value_desc("ext"),
+                                             cl::cat(cat));
+
+static cl::opt<bool> allowComments("allow-comments",
+                                   cl::desc("Allow comments to be introduced with a colon after the part name"),
+                                   cl::cat(cat));
+
 static StringRef toolName;
 static int errorCount;
 
@@ -80,7 +89,15 @@
           line.substr(markerLen - 4).startswith("--- ")))
       continue;
     separator = line.substr(0, markerLen);
-    const StringRef partName = line.substr(markerLen);
+    const StringRef partName = [&] {
+      StringRef partName = line.substr(markerLen);
+      if (allowComments) {
+        auto colonPos = partName.find(':');
+        if (colonPos != StringRef::npos)
+          partName = partName.substr(0, colonPos);
+      }
+      return partName;
+    }();
     if (partName.empty()) {
       error(input, lineNo, "empty part name");
       continue;
@@ -118,6 +135,11 @@
   for (auto &keyValue : partToBegin) {
     partPath.clear();
     sys::path::append(partPath, output, keyValue.first);
+    if (!addFileExtension.empty()) {
+      if (addFileExtension.getValue()[0] != '.')
+        partPath.append(".");
+      partPath.append(addFileExtension.getValue());
+    }
     std::error_code ec =
         sys::fs::create_directories(sys::path::parent_path(partPath));
     if (ec)