Fix width of constant propagation of SInt with zero (#2120)

1 files changed, 1 insertions, 1 deletions

diff --git a/src/main/scala/firrtl/transforms/ConstantPropagation.scala b/src/main/scala/firrtl/transforms/ConstantPropagation.scala
index 0523082d..7106c699 100644
--- a/src/main/scala/firrtl/transforms/ConstantPropagation.scala
+++ b/src/main/scala/firrtl/transforms/ConstantPropagation.scala
@@ -230,7 +230,7 @@ class ConstantPropagation extends Transform with DependencyAPIMigration {
     }
     def simplify(e: Expression, lhs: Literal, rhs: Expression) = lhs match {
       case UIntLiteral(v, _) if v == BigInt(0)                                            => rhs
-      case SIntLiteral(v, _) if v == BigInt(0)                                            => asUInt(rhs, e.tpe)
+      case SIntLiteral(v, _) if v == BigInt(0)                                            => asUInt(pad(rhs, e.tpe), e.tpe)
       case UIntLiteral(v, IntWidth(w)) if v == (BigInt(1) << bitWidth(rhs.tpe).toInt) - 1 => lhs
       case _                                                                              => e
     }