add helper method.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@67989 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/include/llvm/ADT/PointerUnion.h b/include/llvm/ADT/PointerUnion.h
index 8ea1315a736e289e12354c6d58fae7a7cffafe5f..7a4de65656681fb480345e1196c21da8bf49516e 100644 (file)
--- a/include/llvm/ADT/PointerUnion.h
+++ b/include/llvm/ADT/PointerUnion.h
@@ -78,6 +78,8 @@ namespace llvm {
       Val.setInt(1);
     }
     
+    bool isNull() const { return Val.getPointer() == 0; }
+    
     template<typename T>
     int is() const {
       return Val.getInt() == ::llvm::getPointerUnionTypeNum<PT1, PT2>((T*)0);