Refactor Data.toString (#2197)

Provides a more intuitive implementation of toString for Data.
Utilizes the fact that the compiler plugin provides names earlier than
Chisel had in the past so we can accurately guess the name of
signals even in the currently elaborating module.

Co-authored-by: Megan Wachs <megan@sifive.com>
Co-authored-by: Jack Koenig <jack.koenig3@gmail.com>

1 files changed, 14 insertions, 1 deletions

diff --git a/core/src/main/scala/chisel3/internal/firrtl/IR.scala b/core/src/main/scala/chisel3/internal/firrtl/IR.scala
index 1a06cd36..a352c96a 100644
--- a/core/src/main/scala/chisel3/internal/firrtl/IR.scala
+++ b/core/src/main/scala/chisel3/internal/firrtl/IR.scala
@@ -86,6 +86,19 @@ case class Node(id: HasId) extends Arg {
   }
 }
 
+private[chisel3] object Arg {
+  def earlyLocalName(id: HasId): String = id.getOptionRef match {
+    case Some(Index(Node(imm), Node(value))) => s"${earlyLocalName(imm)}[${earlyLocalName(imm)}]"
+    case Some(Index(Node(imm), arg)) => s"${earlyLocalName(imm)}[${arg.localName}]"
+    case Some(Slot(Node(imm), name)) => s"${earlyLocalName(imm)}.$name"
+    case Some(arg) => arg.name
+    case None => id match {
+      case data: Data => data._computeName(None, Some("?")).get
+      case _ => "?"
+    }
+  }
+}
+
 abstract class LitArg(val num: BigInt, widthArg: Width) extends Arg {
   private[chisel3] def forcedWidth = widthArg.known
   private[chisel3] def width: Width = if (forcedWidth) widthArg else Width(minWidth)
@@ -196,7 +209,7 @@ case class Slot(imm: Node, name: String) extends Arg {
     if (immName.isEmpty) name else s"$immName.$name"
   }
 }
-case class Index(imm: Arg, value: Arg) extends Arg {
+case class Index(imm: Node, value: Arg) extends Arg {
   def name: String = s"[$value]"
   override def contextualName(ctx: Component): String = s"${imm.contextualName(ctx)}[${value.contextualName(ctx)}]"
   override def localName: String = s"${imm.localName}[${value.localName}]"