handle optional in flags that aren't present.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@96731 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/include/llvm/CodeGen/DAGISelHeader.h b/include/llvm/CodeGen/DAGISelHeader.h
index 7e6728e..1e808ed 100644
--- a/include/llvm/CodeGen/DAGISelHeader.h
+++ b/include/llvm/CodeGen/DAGISelHeader.h
@@ -672,7 +672,7 @@
       // If this has chain/flag inputs, add them.
       if (EmitNodeInfo & OPFL_Chain)
         Ops.push_back(InputChain);
-      if (EmitNodeInfo & OPFL_Flag)
+      if ((EmitNodeInfo & OPFL_Flag) && InputFlag.getNode() != 0)
         Ops.push_back(InputFlag);
       
       // Create the node.