Convert PreservesAll to explicit invalidates=false

Signed-off-by: Schuyler Eldridge <schuyler.eldridge@ibm.com>

1 files changed, 4 insertions, 2 deletions

diff --git a/src/main/scala/firrtl/passes/RemoveCHIRRTL.scala b/src/main/scala/firrtl/passes/RemoveCHIRRTL.scala
index 67181f2b..8ba783ca 100644
--- a/src/main/scala/firrtl/passes/RemoveCHIRRTL.scala
+++ b/src/main/scala/firrtl/passes/RemoveCHIRRTL.scala
@@ -8,18 +8,20 @@ import firrtl._
 import firrtl.ir._
 import firrtl.Utils._
 import firrtl.Mappers._
-import firrtl.options.{Dependency, PreservesAll}
+import firrtl.options.Dependency
 
 case class MPort(name: String, clk: Expression)
 case class MPorts(readers: ArrayBuffer[MPort], writers: ArrayBuffer[MPort], readwriters: ArrayBuffer[MPort])
 case class DataRef(exp: Expression, male: String, female: String, mask: String, rdwrite: Boolean)
 
-object RemoveCHIRRTL extends Transform with DependencyAPIMigration with PreservesAll[Transform] {
+object RemoveCHIRRTL extends Transform with DependencyAPIMigration {
 
   override def prerequisites = firrtl.stage.Forms.ChirrtlForm ++
     Seq( Dependency(passes.CInferTypes),
          Dependency(passes.CInferMDir) )
 
+  override def invalidates(a: Transform) = false
+
   val ut = UnknownType
   type MPortMap = collection.mutable.LinkedHashMap[String, MPorts]
   type SeqMemSet = collection.mutable.HashSet[String]