Mark fallthrough with LLVM_FALLTHROUGH

llvm-svn: 323986
diff --git a/clang/utils/TableGen/NeonEmitter.cpp b/clang/utils/TableGen/NeonEmitter.cpp
index d4ce6c7..1a95ca4 100644
--- a/clang/utils/TableGen/NeonEmitter.cpp
+++ b/clang/utils/TableGen/NeonEmitter.cpp
@@ -948,7 +948,7 @@
     break;
   case 'c':
     Constant = true;
-  // Fall through
+    LLVM_FALLTHROUGH;
   case 'p':
     Pointer = true;
     Bitwidth = ElementBitwidth;