Index: clang/tools/clang-format/ClangFormat.cpp
===================================================================
--- clang/tools/clang-format/ClangFormat.cpp
+++ clang/tools/clang-format/ClangFormat.cpp
@@ -241,6 +241,30 @@
   }
 }
 
+// Returns an invalid BOM
+static const char *hasInValidBOM(StringRef BufStr) {
+  // Check to see if the buffer has a UTF Byte Order Mark (BOM).
+  // We only support UTF-8 with and without a BOM right now.  See
+  // https://en.wikipedia.org/wiki/Byte_order_mark#Byte_order_marks_by_encoding
+  // for more information.
+  const char *InvalidBOM =
+      llvm::StringSwitch<const char *>(BufStr)
+          .StartsWith(llvm::StringLiteral::withInnerNUL("\x00\x00\xFE\xFF"),
+                      "UTF-32 (BE)")
+          .StartsWith(llvm::StringLiteral::withInnerNUL("\xFF\xFE\x00\x00"),
+                      "UTF-32 (LE)")
+          .StartsWith("\xFE\xFF", "UTF-16 (BE)")
+          .StartsWith("\xFF\xFE", "UTF-16 (LE)")
+          .StartsWith("\x2B\x2F\x76", "UTF-7")
+          .StartsWith("\xF7\x64\x4C", "UTF-1")
+          .StartsWith("\xDD\x73\x66\x73", "UTF-EBCDIC")
+          .StartsWith("\x0E\xFE\xFF", "SCSU")
+          .StartsWith("\xFB\xEE\x28", "BOCU-1")
+          .StartsWith("\x84\x31\x95\x33", "GB-18030")
+          .Default(nullptr);
+  return InvalidBOM;
+}
+
 // Returns true on error.
 static bool format(StringRef FileName) {
   if (!OutputXML && Inplace && FileName == "-") {
@@ -260,26 +284,9 @@
   if (Code->getBufferSize() == 0)
     return false; // Empty files are formatted correctly.
 
-  // Check to see if the buffer has a UTF Byte Order Mark (BOM).
-  // We only support UTF-8 with and without a BOM right now.  See
-  // https://en.wikipedia.org/wiki/Byte_order_mark#Byte_order_marks_by_encoding
-  // for more information.
   StringRef BufStr = Code->getBuffer();
-  const char *InvalidBOM =
-      llvm::StringSwitch<const char *>(BufStr)
-          .StartsWith(llvm::StringLiteral::withInnerNUL("\x00\x00\xFE\xFF"),
-                      "UTF-32 (BE)")
-          .StartsWith(llvm::StringLiteral::withInnerNUL("\xFF\xFE\x00\x00"),
-                      "UTF-32 (LE)")
-          .StartsWith("\xFE\xFF", "UTF-16 (BE)")
-          .StartsWith("\xFF\xFE", "UTF-16 (LE)")
-          .StartsWith("\x2B\x2F\x76", "UTF-7")
-          .StartsWith("\xF7\x64\x4C", "UTF-1")
-          .StartsWith("\xDD\x73\x66\x73", "UTF-EBCDIC")
-          .StartsWith("\x0E\xFE\xFF", "SCSU")
-          .StartsWith("\xFB\xEE\x28", "BOCU-1")
-          .StartsWith("\x84\x31\x95\x33", "GB-18030")
-          .Default(nullptr);
+
+  const char *InvalidBOM = hasInValidBOM(BufStr);
 
   if (InvalidBOM) {
     errs() << "error: encoding with unsupported byte order mark \""
@@ -370,6 +377,38 @@
   OS << clang::getClangToolFullVersion("clang-format") << '\n';
 }
 
+// Dump the configuration.
+static unsigned dumpConfig(StringRef AssumeFileName) {
+  StringRef FileName;
+  std::unique_ptr<llvm::MemoryBuffer> Code;
+  if (FileNames.empty()) {
+    // We can't read the code to detect the language if there's no
+    // file name, so leave Code empty here.
+    FileName = AssumeFileName;
+  } else {
+    // Read in the code in case the filename alone isn't enough to
+    // detect the language.
+    ErrorOr<std::unique_ptr<MemoryBuffer>> CodeOrErr =
+        MemoryBuffer::getFileOrSTDIN(FileNames[0]);
+    if (std::error_code EC = CodeOrErr.getError()) {
+      llvm::errs() << EC.message() << "\n";
+      return 1;
+    }
+    FileName = (FileNames[0] == "-") ? AssumeFileName : FileNames[0];
+    Code = std::move(CodeOrErr.get());
+  }
+  llvm::Expected<clang::format::FormatStyle> FormatStyle =
+      clang::format::getStyle(Style, FileName, FallbackStyle,
+                              Code ? Code->getBuffer() : "");
+  if (!FormatStyle) {
+    llvm::errs() << llvm::toString(FormatStyle.takeError()) << "\n";
+    return 1;
+  }
+  std::string Config = clang::format::configurationAsText(*FormatStyle);
+  outs() << Config << "\n";
+  return 0;
+}
+
 int main(int argc, const char **argv) {
   llvm::InitLLVM X(argc, argv);
 
@@ -391,34 +430,7 @@
   }
 
   if (DumpConfig) {
-    StringRef FileName;
-    std::unique_ptr<llvm::MemoryBuffer> Code;
-    if (FileNames.empty()) {
-      // We can't read the code to detect the language if there's no
-      // file name, so leave Code empty here.
-      FileName = AssumeFileName;
-    } else {
-      // Read in the code in case the filename alone isn't enough to
-      // detect the language.
-      ErrorOr<std::unique_ptr<MemoryBuffer>> CodeOrErr =
-          MemoryBuffer::getFileOrSTDIN(FileNames[0]);
-      if (std::error_code EC = CodeOrErr.getError()) {
-        llvm::errs() << EC.message() << "\n";
-        return 1;
-      }
-      FileName = (FileNames[0] == "-") ? AssumeFileName : FileNames[0];
-      Code = std::move(CodeOrErr.get());
-    }
-    llvm::Expected<clang::format::FormatStyle> FormatStyle =
-        clang::format::getStyle(Style, FileName, FallbackStyle,
-                                Code ? Code->getBuffer() : "");
-    if (!FormatStyle) {
-      llvm::errs() << llvm::toString(FormatStyle.takeError()) << "\n";
-      return 1;
-    }
-    std::string Config = clang::format::configurationAsText(*FormatStyle);
-    outs() << Config << "\n";
-    return 0;
+    return dumpConfig(AssumeFileName);
   }
 
   bool Error = false;