fix an issue where the verifier would reject a function whose entry

block had its address taken even if the blockaddress was dead.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@85706 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/BasicBlock.h

@@ -240,6 +240,10 @@ public:
   /// hasAddressTaken - returns true if there are any uses of this basic block
   /// other than direct branches, switches, etc. to it.
   bool hasAddressTaken() const { return SubclassData != 0; }
+                     
+  /// removeDeadBlockAddress - If there is a blockaddress node for this basic
+  /// block, try to remove it and any dead constant users of it.
+  void removeDeadBlockAddress();
 private:
   /// AdjustBlockAddressRefCount - BasicBlock stores the number of BlockAddress
   /// objects using it.  This is almost always 0, sometimes one, possibly but