Index: llvm/include/llvm/MC/MCCodeView.h
===================================================================
--- llvm/include/llvm/MC/MCCodeView.h
+++ llvm/include/llvm/MC/MCCodeView.h
@@ -161,7 +161,7 @@
   ~CodeViewContext();
 
   bool isValidFileNumber(unsigned FileNumber) const;
-  bool addFile(unsigned FileNumber, StringRef Filename);
+  bool addFile(unsigned FileNumber, StringRef Filename, StringRef Checksum, uint8_t ChecksumKind);
   ArrayRef<StringRef> getFilenames() { return Filenames; }
 
   /// Records the function id of a normal function. Returns false if the
@@ -296,6 +296,9 @@
   /// An array of absolute paths. Eventually this may include the file checksum.
   SmallVector<StringRef, 4> Filenames;
 
+  // Map from filename to checksum.
+  StringMap<std::pair<StringRef, uint8_t>> Checksums;
+
   /// The offset of the first and last .cv_loc directive for a given function
   /// id.
   std::map<unsigned, std::pair<size_t, size_t>> MCCVLineStartStop;
Index: llvm/include/llvm/MC/MCStreamer.h
===================================================================
--- llvm/include/llvm/MC/MCStreamer.h
+++ llvm/include/llvm/MC/MCStreamer.h
@@ -732,7 +732,7 @@
   /// \brief Associate a filename with a specified logical file number.  This
   /// implements the '.cv_file 4 "foo.c"' assembler directive. Returns true on
   /// success.
-  virtual bool EmitCVFileDirective(unsigned FileNo, StringRef Filename);
+  virtual bool EmitCVFileDirective(unsigned FileNo, StringRef Filename, StringRef Checksum, uint8_t ChecksumKind);
 
   /// \brief Introduces a function id for use with .cv_loc.
   virtual bool EmitCVFuncIdDirective(unsigned FunctionId);
Index: llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp
===================================================================
--- llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp
+++ llvm/lib/CodeGen/AsmPrinter/CodeViewDebug.cpp
@@ -159,7 +159,9 @@
   if (Insertion.second) {
     // We have to compute the full filepath and emit a .cv_file directive.
     StringRef FullPath = getFullFilepath(F);
-    bool Success = OS.EmitCVFileDirective(NextId, FullPath);
+    StringRef Checksum = F->getChecksum();
+    uint8_t ChecksumKind = static_cast<uint8_t>(F->getChecksumKind());
+    bool Success = OS.EmitCVFileDirective(NextId, FullPath, Checksum, ChecksumKind);
     (void)Success;
     assert(Success && ".cv_file directive failed");
   }
Index: llvm/lib/MC/MCAsmStreamer.cpp
===================================================================
--- llvm/lib/MC/MCAsmStreamer.cpp
+++ llvm/lib/MC/MCAsmStreamer.cpp
@@ -225,7 +225,7 @@
                              StringRef FileName) override;
   MCSymbol *getDwarfLineTableSymbol(unsigned CUID) override;
 
-  bool EmitCVFileDirective(unsigned FileNo, StringRef Filename) override;
+  bool EmitCVFileDirective(unsigned FileNo, StringRef Filename, StringRef Checksum, uint8_t ChecksumKind) override;
   bool EmitCVFuncIdDirective(unsigned FuncId) override;
   bool EmitCVInlineSiteIdDirective(unsigned FunctionId, unsigned IAFunc,
                                    unsigned IAFile, unsigned IALine,
@@ -1120,13 +1120,17 @@
   return MCStreamer::getDwarfLineTableSymbol(0);
 }
 
-bool MCAsmStreamer::EmitCVFileDirective(unsigned FileNo, StringRef Filename) {
-  if (!getContext().getCVContext().addFile(FileNo, Filename))
+bool MCAsmStreamer::EmitCVFileDirective(unsigned FileNo, StringRef Filename, StringRef Checksum, uint8_t ChecksumKind) {
+  if (!getContext().getCVContext().addFile(FileNo, Filename, Checksum, ChecksumKind))
     return false;
 
   OS << "\t.cv_file\t" << FileNo << ' ';
 
   PrintQuotedString(Filename, OS);
+  PrintQuotedString(Checksum, OS);
+
+  OS << ChecksumKind;
+
   EmitEOL();
   return true;
 }
Index: llvm/lib/MC/MCCodeView.cpp
===================================================================
--- llvm/lib/MC/MCCodeView.cpp
+++ llvm/lib/MC/MCCodeView.cpp
@@ -44,7 +44,7 @@
   return false;
 }
 
-bool CodeViewContext::addFile(unsigned FileNumber, StringRef Filename) {
+bool CodeViewContext::addFile(unsigned FileNumber, StringRef Filename, StringRef Checksum, uint8_t ChecksumKind) {
   assert(FileNumber > 0);
   Filename = addToStringTable(Filename);
   unsigned Idx = FileNumber - 1;
@@ -62,6 +62,9 @@
   Filename = addToStringTable(Filename);
 
   Filenames[Idx] = Filename;
+
+  Checksums.insert(std::make_pair(Filename, std::make_pair(Checksum,ChecksumKind)));
+
   return true;
 }
 
@@ -181,9 +184,17 @@
   // emit checksums.
   for (StringRef Filename : Filenames) {
     OS.EmitIntValue(getStringTableOffset(Filename), 4);
-    // Zero the next two fields and align back to 4 bytes. This indicates that
-    // no checksum is present.
-    OS.EmitIntValue(0, 4);
+
+    std::pair<StringRef, uint8_t> Checksum = Checksums[Filename];
+    if (!Checksum.second) {
+      // There is no checksum.
+      OS.EmitIntValue(0, 4);
+      return;
+    }
+    OS.EmitIntValue(static_cast<uint8_t>(Checksum.first.size()), 1);
+    OS.EmitIntValue(Checksum.second, 1);
+    OS.EmitBytes(Checksum.first);
+    OS.EmitValueToAlignment(4);
   }
 
   OS.EmitLabel(FileEnd);
Index: llvm/lib/MC/MCParser/AsmParser.cpp
===================================================================
--- llvm/lib/MC/MCParser/AsmParser.cpp
+++ llvm/lib/MC/MCParser/AsmParser.cpp
@@ -3457,6 +3457,8 @@
   SMLoc FileNumberLoc = getTok().getLoc();
   int64_t FileNumber;
   std::string Filename;
+  std::string Checksum;
+  int64_t ChecksumKind;
 
   if (parseIntToken(FileNumber,
                     "expected file number in '.cv_file' directive") ||
@@ -3466,11 +3468,15 @@
       // Usually directory and filename are together, otherwise just
       // directory. Allow the strings to have escaped octal character sequence.
       parseEscapedString(Filename) ||
+      check(getTok().isNot(AsmToken::String),
+            "unexpected token in '.cv_file' directive") ||
+      parseEscapedString(Checksum) ||
+      parseIntToken(ChecksumKind, "expected checksum kind in '.cv_file' directive") ||
       parseToken(AsmToken::EndOfStatement,
                  "unexpected token in '.cv_file' directive"))
     return true;
 
-  if (!getStreamer().EmitCVFileDirective(FileNumber, Filename))
+  if (!getStreamer().EmitCVFileDirective(FileNumber, Filename, Checksum, static_cast<uint8_t>(ChecksumKind)))
     return Error(FileNumberLoc, "file number already allocated");
 
   return false;
Index: llvm/lib/MC/MCStreamer.cpp
===================================================================
--- llvm/lib/MC/MCStreamer.cpp
+++ llvm/lib/MC/MCStreamer.cpp
@@ -224,8 +224,8 @@
     report_fatal_error("No open frame");
 }
 
-bool MCStreamer::EmitCVFileDirective(unsigned FileNo, StringRef Filename) {
-  return getContext().getCVContext().addFile(FileNo, Filename);
+bool MCStreamer::EmitCVFileDirective(unsigned FileNo, StringRef Filename, StringRef Checksum, uint8_t ChecksumKind) {
+  return getContext().getCVContext().addFile(FileNo, Filename, Checksum, ChecksumKind);
 }
 
 bool MCStreamer::EmitCVFuncIdDirective(unsigned FunctionId) {