- , BlockSet, emptyBlockSet, elemBlockSet, extendBlockSet)
-import CmmExpr ( UserOfLocalRegs(..) ) --for an instance
+ , BlockSet, emptyBlockSet, unitBlockSet, elemBlockSet, extendBlockSet
+ , delFromBlockEnv, foldBlockEnv', mapBlockEnv
+ , eltsBlockEnv, isNullBEnv, plusBlockEnv)
+import CmmExpr ( UserOfLocalRegs(..) )
+import PprCmm()