Silence a bunch of implicit fallthrough warnings

llvm-svn: 321114
diff --git a/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp b/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
index 3103709..d799544 100644
--- a/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
+++ b/llvm/lib/CodeGen/AsmPrinter/AsmPrinter.cpp
@@ -2033,6 +2033,7 @@
     }
   }
   // else fallthrough
+  LLVM_FALLTHROUGH;
 
   // The MC library also has a right-shift operator, but it isn't consistently
   // signed or unsigned between different targets.