Merge pull request #919 from seldridge/f764.6

- Add, but do not use Options-mirroring Annotations

1 files changed, 9 insertions, 1 deletions

diff --git a/src/main/scala/firrtl/transforms/DeadCodeElimination.scala b/src/main/scala/firrtl/transforms/DeadCodeElimination.scala
index 523c997b..8f9fad46 100644
--- a/src/main/scala/firrtl/transforms/DeadCodeElimination.scala
+++ b/src/main/scala/firrtl/transforms/DeadCodeElimination.scala
@@ -11,6 +11,8 @@ import firrtl.Mappers._
 import firrtl.WrappedExpression._
 import firrtl.Utils.{throwInternalError, toWrappedExpression, kind}
 import firrtl.MemoizedHash._
+import firrtl.options.RegisteredTransform
+import scopt.OptionParser
 
 import collection.mutable
 import java.io.{File, FileWriter}
@@ -30,10 +32,16 @@ import java.io.{File, FileWriter}
   * circumstances of their instantiation in their parent module, they will still not be removed. To
   * remove such modules, use the [[NoDedupAnnotation]] to prevent deduplication.
   */
-class DeadCodeElimination extends Transform with ResolvedAnnotationPaths {
+class DeadCodeElimination extends Transform with ResolvedAnnotationPaths with RegisteredTransform {
   def inputForm = LowForm
   def outputForm = LowForm
 
+  def addOptions(parser: OptionParser[AnnotationSeq]): Unit = parser
+    .opt[Unit]("no-dce")
+    .action( (x, c) => c :+ NoDCEAnnotation )
+    .maxOccurs(1)
+    .text("Do NOT run dead code elimination")
+
   /** Based on LogicNode ins CheckCombLoops, currently kind of faking it */
   private type LogicNode = MemoizedHash[WrappedExpression]
   private object LogicNode {