[DWARFv5] MC support for MD5 file checksums

Extend .file directive syntax to allow specifying an MD5 checksum for
the source file.  Emit the checksums in DWARF v5 line tables.

llvm-svn: 322134
diff --git a/llvm/lib/MC/MCStreamer.cpp b/llvm/lib/MC/MCStreamer.cpp
index af1fc52..a678427 100644
--- a/llvm/lib/MC/MCStreamer.cpp
+++ b/llvm/lib/MC/MCStreamer.cpp
@@ -194,8 +194,10 @@
 
 unsigned MCStreamer::EmitDwarfFileDirective(unsigned FileNo,
                                             StringRef Directory,
-                                            StringRef Filename, unsigned CUID) {
-  return getContext().getDwarfFile(Directory, Filename, FileNo, CUID);
+                                            StringRef Filename,
+                                            MD5::MD5Result *Checksum,
+                                            unsigned CUID) {
+  return getContext().getDwarfFile(Directory, Filename, FileNo, Checksum, CUID);
 }
 
 void MCStreamer::EmitDwarfLocDirective(unsigned FileNo, unsigned Line,