[DebugInfo] IR/Bitcode changes for DISubprogram flags.

Packing the flags into one bitcode word will save effort in
adding new flags in the future.

Differential Revision: https://reviews.llvm.org/D54755

llvm-svn: 347806
diff --git a/llvm/lib/AsmParser/LLLexer.cpp b/llvm/lib/AsmParser/LLLexer.cpp
index 0452145..eab7ec8 100644
--- a/llvm/lib/AsmParser/LLLexer.cpp
+++ b/llvm/lib/AsmParser/LLLexer.cpp
@@ -905,6 +905,11 @@
     return lltok::DIFlag;
   }
 
+  if (Keyword.startswith("DISPFlag")) {
+    StrVal.assign(Keyword.begin(), Keyword.end());
+    return lltok::DISPFlag;
+  }
+
   if (Keyword.startswith("CSK_")) {
     StrVal.assign(Keyword.begin(), Keyword.end());
     return lltok::ChecksumKind;