1 files changed, 7 insertions, 0 deletions
diff --git a/src/main/scala/chisel3/util/BitPat.scala b/src/main/scala/chisel3/util/BitPat.scala
index 12a421a0..5a40d312 100644
--- a/src/main/scala/chisel3/util/BitPat.scala
+++ b/src/main/scala/chisel3/util/BitPat.scala
@@ -119,4 +119,11 @@ sealed class BitPat(val value: BigInt, val mask: BigInt, width: Int) extends Sou
     !(this === that)
   }
 
+  override def toString = {
+    "BitPat(" +
+      (0 until width).map(i =>
+        if (((mask >> i) & 1) == 1) if (((value >> i) & 1) == 1)  "1" else "0" else "?"
+      ).reverse.reduce(_ + _) +
+    ")"
+  }
 }