Merge branch 'master' into tobits-deprecation

1 files changed, 13 insertions, 0 deletions

diff --git a/chiselFrontend/src/main/scala/chisel3/core/Data.scala b/chiselFrontend/src/main/scala/chisel3/core/Data.scala
index 0e473e7e..86858e5d 100644
--- a/chiselFrontend/src/main/scala/chisel3/core/Data.scala
+++ b/chiselFrontend/src/main/scala/chisel3/core/Data.scala
@@ -173,7 +173,19 @@ abstract class Data extends HasId {
   private[core] def width: Width
   private[core] def legacyConnect(that: Data)(implicit sourceInfo: SourceInfo): Unit
 
+  /** cloneType must be defined for any Chisel object extending Data.
+    * It is responsible for constructing a basic copy of the object being cloned.
+    * If cloneType needs to recursively clone elements of an object, it should call
+    * the cloneType methods on those elements.
+    * @return a copy of the object.
+    */
   def cloneType: this.type
+
+  /** chiselCloneType is called at the top-level of a clone chain.
+    * It calls the client's cloneType() method to construct a basic copy of the object being cloned,
+    * then performs any fixups required to reconstruct the appropriate core state of the cloned object.
+    * @return a copy of the object with appropriate core state.
+    */
   def chiselCloneType: this.type = {
     // Call the user-supplied cloneType method
     val clone = this.cloneType
@@ -181,6 +193,7 @@ abstract class Data extends HasId {
     //TODO(twigg): Do recursively for better error messages
     for((clone_elem, source_elem) <- clone.allElements zip this.allElements) {
       clone_elem.binding = UnboundBinding(source_elem.binding.direction)
+      Data.setFirrtlDirection(clone_elem, Data.getFirrtlDirection(source_elem))
     }
     clone
   }