infer results of a pattern from implicit defs.  This allows you to do something 
like this:

 def : Pat<(add ...),
           (FOOINST)>;

When fooinst only has a single implicit def (e.g. to R1).  This will be handled
as if written as (set R1, (FOOINST ...))



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@98897 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/utils/TableGen/CodeGenDAGPatterns.h b/utils/TableGen/CodeGenDAGPatterns.h
index 44f82fe..c32b23a 100644
--- a/utils/TableGen/CodeGenDAGPatterns.h
+++ b/utils/TableGen/CodeGenDAGPatterns.h
@@ -88,6 +88,10 @@
       return TypeVec;
     }
     
+    bool isVoid() const {
+      return TypeVec.size() == 1 && TypeVec[0] == MVT::isVoid;
+    }
+    
     /// hasIntegerTypes - Return true if this TypeSet contains any integer value
     /// types.
     bool hasIntegerTypes() const;