From 35cfeae466d441df5f10c2644c6d7c6da218db81 Mon Sep 17 00:00:00 2001
From: Aditya Naik <aditya.naik@sifive.com>
Date: Tue, 26 May 2026 15:08:56 -0700
Subject: [PATCH 1/3] Move D/I tests

---
 .../hierarchy/DefinitionSpec.scala            |   1 +
 .../experimental/hierarchy/Examples.scala     | 121 +++++++++---------
 .../experimental/hierarchy/InstanceSpec.scala |   7 +-
 .../hierarchy/SeparateElaborationSpec.scala   |   2 +-
 4 files changed, 70 insertions(+), 61 deletions(-)
 rename src/test/{scala-2 => scala}/chiselTests/experimental/hierarchy/DefinitionSpec.scala (99%)
 rename src/test/{scala-2 => scala}/chiselTests/experimental/hierarchy/Examples.scala (77%)
 rename src/test/{scala-2 => scala}/chiselTests/experimental/hierarchy/InstanceSpec.scala (99%)
 rename src/test/{scala-2 => scala}/chiselTests/experimental/hierarchy/SeparateElaborationSpec.scala (99%)

diff --git a/src/test/scala-2/chiselTests/experimental/hierarchy/DefinitionSpec.scala b/src/test/scala/chiselTests/experimental/hierarchy/DefinitionSpec.scala
similarity index 99%
rename from src/test/scala-2/chiselTests/experimental/hierarchy/DefinitionSpec.scala
rename to src/test/scala/chiselTests/experimental/hierarchy/DefinitionSpec.scala
index 0356b06d5b9..b459b8058d4 100644
--- a/src/test/scala-2/chiselTests/experimental/hierarchy/DefinitionSpec.scala
+++ b/src/test/scala/chiselTests/experimental/hierarchy/DefinitionSpec.scala
@@ -8,6 +8,7 @@ import chisel3.experimental.BaseModule
 import chisel3.experimental.hierarchy.{instantiable, public, Definition, Instance}
 import chisel3.testing.scalatest.FileCheck
 import chiselTests.experimental.ExtensionMethods.ChiselStageHelpers
+import firrtl.annoSeqToSeq
 import circt.stage.ChiselStage
 import org.scalatest.funspec.AnyFunSpec
 import org.scalatest.matchers.should.Matchers
diff --git a/src/test/scala-2/chiselTests/experimental/hierarchy/Examples.scala b/src/test/scala/chiselTests/experimental/hierarchy/Examples.scala
similarity index 77%
rename from src/test/scala-2/chiselTests/experimental/hierarchy/Examples.scala
rename to src/test/scala/chiselTests/experimental/hierarchy/Examples.scala
index 39a5efbc7cd..469bd9c38ed 100644
--- a/src/test/scala-2/chiselTests/experimental/hierarchy/Examples.scala
+++ b/src/test/scala/chiselTests/experimental/hierarchy/Examples.scala
@@ -12,7 +12,7 @@ import scala.collection.immutable.SeqMap
 object Examples {
   import Annotations._
   @instantiable
-  class AddOne extends Module {
+  class AddOne extends Module with IsInstantiable {
     @public val in = IO(Input(UInt(32.W)))
     @public val out = IO(Output(UInt(32.W)))
     @public val innerWire = Wire(UInt(32.W))
@@ -20,7 +20,7 @@ object Examples {
     out := innerWire
   }
   @instantiable
-  class AddOneWithAnnotation extends Module {
+  class AddOneWithAnnotation extends Module with IsInstantiable {
     @public val in = IO(Input(UInt(32.W)))
     @public val out = IO(Output(UInt(32.W)))
     @public val innerWire = Wire(UInt(32.W))
@@ -29,7 +29,7 @@ object Examples {
     out := innerWire
   }
   @instantiable
-  class AddOneWithAbsoluteAnnotation extends Module {
+  class AddOneWithAbsoluteAnnotation extends Module with IsInstantiable {
     @public val in = IO(Input(UInt(32.W)))
     @public val out = IO(Output(UInt(32.W)))
     @public val innerWire = Wire(UInt(32.W))
@@ -38,19 +38,19 @@ object Examples {
     out := innerWire
   }
   @instantiable
-  class AddOneParameterized(width: Int) extends Module {
+  class AddOneParameterized(width: Int) extends Module with IsInstantiable {
     @public val in = IO(Input(UInt(width.W)))
     @public val out = IO(Output(UInt(width.W)))
     out := in + 1.U
   }
-  class AddOneWithNested(width: Int) extends Module {
+  class AddOneWithNested(width: Int) extends Module with IsInstantiable {
     @public val in = IO(Input(UInt(width.W)))
     @public val out = IO(Output(UInt(width.W)))
     val addOneDef = Seq.fill(3)(Definition(new AddOne))
     out := in + 1.U
   }
   @instantiable
-  class AddOneBlackBox extends ExtModule {
+  class AddOneBlackBox extends ExtModule with IsInstantiable {
     @public val io = FlatIO(new Bundle {
       val in = Input(UInt(32.W))
       val out = Output(UInt(32.W))
@@ -58,7 +58,7 @@ object Examples {
   }
 
   @instantiable
-  class AddTwo extends Module {
+  class AddTwo extends Module with IsInstantiable {
     @public val in = IO(Input(UInt(32.W)))
     @public val out = IO(Output(UInt(32.W)))
     @public val definition = Definition(new AddOne)
@@ -69,7 +69,7 @@ object Examples {
     out := i1.out
   }
   @instantiable
-  class AddTwoMixedModules extends Module {
+  class AddTwoMixedModules extends Module with IsInstantiable {
     @public val in = IO(Input(UInt(32.W)))
     @public val out = IO(Output(UInt(32.W)))
     val definition = Definition(new AddOne)
@@ -81,7 +81,8 @@ object Examples {
   }
   @instantiable
   class AddTwoParameterized(width: Int, makeParameterizedOnes: Int => Seq[Instance[AddOneParameterized]])
-      extends Module {
+      extends Module
+      with IsInstantiable {
     val in = IO(Input(UInt(width.W)))
     val out = IO(Output(UInt(width.W)))
     val addOnes = makeParameterizedOnes(width)
@@ -90,13 +91,15 @@ object Examples {
     addOnes.zip(addOnes.tail).foreach { case (head, tail) => tail.in := head.out }
   }
   @instantiable
-  class AddTwoWithNested(width: Int, makeParameterizedOnes: Int => Seq[Instance[AddOneWithNested]]) extends Module {
+  class AddTwoWithNested(width: Int, makeParameterizedOnes: Int => Seq[Instance[AddOneWithNested]])
+      extends Module
+      with IsInstantiable {
     val in = IO(Input(UInt(width.W)))
     val out = IO(Output(UInt(width.W)))
     val addOnes = makeParameterizedOnes(width)
   }
   @instantiable
-  class AddTwoDefinitionArgument(definition: Definition[AddOne]) extends Module {
+  class AddTwoDefinitionArgument(definition: Definition[AddOne]) extends Module with IsInstantiable {
     @public val in = IO(Input(UInt(32.W)))
     @public val out = IO(Output(UInt(32.W)))
     @public val i0: Instance[AddOne] = Instance(definition)
@@ -107,7 +110,7 @@ object Examples {
   }
 
   @instantiable
-  class AddFour extends Module {
+  class AddFour extends Module with IsInstantiable {
     @public val in = IO(Input(UInt(32.W)))
     @public val out = IO(Output(UInt(32.W)))
     @public val definition = Definition(new AddTwoMixedModules)
@@ -118,7 +121,7 @@ object Examples {
     out := i1.out
   }
   @instantiable
-  class AggregatePortModule extends Module {
+  class AggregatePortModule extends Module with IsInstantiable {
     @public val io = IO(new Bundle {
       val in = Input(UInt(32.W))
       val out = Output(UInt(32.W))
@@ -126,11 +129,11 @@ object Examples {
     io.out := io.in
   }
   @instantiable
-  class WireContainer {
+  class WireContainer extends IsInstantiable {
     @public val innerWire = Wire(UInt(32.W))
   }
   @instantiable
-  class AddOneWithInstantiableWire extends Module {
+  class AddOneWithInstantiableWire extends Module with IsInstantiable {
     @public val in = IO(Input(UInt(32.W)))
     @public val out = IO(Output(UInt(32.W)))
     @public val wireContainer = new WireContainer()
@@ -138,11 +141,11 @@ object Examples {
     out := wireContainer.innerWire
   }
   @instantiable
-  class AddOneContainer {
+  class AddOneContainer extends IsInstantiable {
     @public val i0 = Module(new AddOne)
   }
   @instantiable
-  class AddOneWithInstantiableModule extends Module {
+  class AddOneWithInstantiableModule extends Module with IsInstantiable {
     @public val in = IO(Input(UInt(32.W)))
     @public val out = IO(Output(UInt(32.W)))
     @public val moduleContainer = new AddOneContainer()
@@ -150,12 +153,12 @@ object Examples {
     out := moduleContainer.i0.out
   }
   @instantiable
-  class AddOneInstanceContainer {
+  class AddOneInstanceContainer extends IsInstantiable {
     val definition = Definition(new AddOne)
     @public val i0 = Instance(definition)
   }
   @instantiable
-  class AddOneWithInstantiableInstance extends Module {
+  class AddOneWithInstantiableInstance extends Module with IsInstantiable {
     @public val in = IO(Input(UInt(32.W)))
     @public val out = IO(Output(UInt(32.W)))
     @public val instanceContainer = new AddOneInstanceContainer()
@@ -163,11 +166,11 @@ object Examples {
     out := instanceContainer.i0.out
   }
   @instantiable
-  class AddOneContainerContainer {
+  class AddOneContainerContainer extends IsInstantiable {
     @public val container = new AddOneContainer
   }
   @instantiable
-  class AddOneWithInstantiableInstantiable extends Module {
+  class AddOneWithInstantiableInstantiable extends Module with IsInstantiable {
     @public val in = IO(Input(UInt(32.W)))
     @public val out = IO(Output(UInt(32.W)))
     @public val containerContainer = new AddOneContainerContainer()
@@ -175,12 +178,12 @@ object Examples {
     out := containerContainer.container.i0.out
   }
   @instantiable
-  class Viewer(val y: AddTwo, markPlease: Boolean) {
+  class Viewer(val y: AddTwo, markPlease: Boolean) extends IsInstantiable {
     @public val x = y
     if (markPlease) mark(x.i0.innerWire, "first")
   }
   @instantiable
-  class ViewerParent(val x: AddTwo, markHere: Boolean, markThere: Boolean) extends Module {
+  class ViewerParent(val x: AddTwo, markHere: Boolean, markThere: Boolean) extends Module with IsInstantiable {
     @public val viewer = new Viewer(x, markThere)
     if (markHere) mark(viewer.x.i0.innerWire, "second")
   }
@@ -189,7 +192,7 @@ object Examples {
     @public val (x, y) = (Wire(UInt(3.W)), Wire(UInt(3.W)))
   }
   @instantiable
-  class LazyVal() extends Module {
+  class LazyVal() extends Module with IsInstantiable {
     @public val x = Wire(UInt(3.W))
     @public lazy val y = "Hi"
   }
@@ -200,73 +203,73 @@ object Examples {
     @public val x = Wire(UInt(3.W))
   }
   @instantiable
-  class HasList() extends Module {
+  class HasList() extends Module with IsInstantiable {
     @public val y = List(1, 2, 3)
     @public val x = List.fill(3)(Wire(UInt(3.W)))
   }
   @instantiable
-  class HasSeq() extends Module {
+  class HasSeq() extends Module with IsInstantiable {
     @public val y = Seq(1, 2, 3)
     @public val x = Seq.fill(3)(Wire(UInt(3.W)))
   }
   @instantiable
-  class HasOption() extends Module {
+  class HasOption() extends Module with IsInstantiable {
     @public val x: Option[UInt] = Some(Wire(UInt(3.W)))
   }
   @instantiable
-  class HasEither() extends Module {
+  class HasEither() extends Module with IsInstantiable {
     @public val x: Either[Bool, UInt] = Right(Wire(UInt(3.W)).suggestName("x"))
     @public val y: Either[Bool, UInt] = Left(Wire(Bool()).suggestName("y"))
   }
   @instantiable
-  class HasTuple2() extends Module {
+  class HasTuple2() extends Module with IsInstantiable {
     val x = Wire(UInt(3.W))
     val y = Wire(Bool())
     @public val xy = (x, y)
   }
   @instantiable
-  class HasTuple5() extends Module {
+  class HasTuple5() extends Module with IsInstantiable {
     val wire = Wire(UInt(3.W))
     val inst = Module(new AddOne)
     @public val tup = (3, wire, "hi", inst, List(1, 2, 3))
   }
   @instantiable
-  class HasHasTarget() extends Module {
+  class HasHasTarget() extends Module with IsInstantiable {
     val sram = SRAM(1024, UInt(8.W), 1, 1, 0)
     @public val x: HasTarget = sram.underlying.get
   }
   @instantiable
-  class HasVec() extends Module {
+  class HasVec() extends Module with IsInstantiable {
     @public val x = VecInit(1.U, 2.U, 3.U)
   }
   @instantiable
-  class HasIndexedVec() extends Module {
+  class HasIndexedVec() extends Module with IsInstantiable {
     val x = VecInit(1.U, 2.U, 3.U)
     @public val y = x(1)
   }
   @instantiable
-  class HasSubFieldAccess extends Module {
+  class HasSubFieldAccess extends Module with IsInstantiable {
     val in = IO(Input(Valid(UInt(8.W))))
     @public val valid = in.valid
     @public val bits = in.bits
   }
   @instantiable
-  class HasPublicConstructorArgs(@public val int: Int) extends Module {
+  class HasPublicConstructorArgs(@public val int: Int) extends Module with IsInstantiable {
     @public val x = Wire(UInt(3.W))
   }
   @instantiable
-  class InstantiatesHasVec() extends Module {
+  class InstantiatesHasVec() extends Module with IsInstantiable {
     @public val i0 = Instance(Definition(new HasVec()))
     @public val i1 = Module(new HasVec())
   }
   @instantiable
-  class HasUninferredReset() extends Module {
+  class HasUninferredReset() extends Module with IsInstantiable {
     @public val in = IO(Input(UInt(3.W)))
     @public val out = IO(Output(UInt(3.W)))
     out := RegNext(in)
   }
   @instantiable
-  abstract class HasBlah() extends Module {
+  abstract class HasBlah() extends Module with IsInstantiable {
     @public val blah: Int
   }
 
@@ -275,12 +278,12 @@ object Examples {
     val blah = 10
   }
   @instantiable
-  class HasTypeParams[D <: Data](d: D) extends Module {
+  class HasTypeParams[D <: Data](d: D) extends Module with IsInstantiable {
     @public val blah = Wire(d)
   }
 
   @instantiable
-  class HasMultipleTypeParamsInside extends Module {
+  class HasMultipleTypeParamsInside extends Module with IsInstantiable {
     val tpDef0 = Definition(new HasTypeParams(Bool()))
     val tpDef1 = Definition(new HasTypeParams(UInt(4.W)))
     val i00 = Instance(tpDef0)
@@ -290,35 +293,35 @@ object Examples {
   }
 
   @instantiable
-  class HasMems() extends Module {
+  class HasMems() extends Module with IsInstantiable {
     @public val mem = Mem(8, UInt(32.W))
     @public val syncReadMem = SyncReadMem(8, UInt(32.W))
   }
 
   @instantiable
-  class LeafInstantiable(val bundle: Data) {
-    @public val bundle = bundle
+  class LeafInstantiable(val _bundle: Data) extends IsInstantiable {
+    @public val bundle = _bundle
   }
 
   @instantiable
-  class NestedInstantiable(val in: LeafInstantiable, val out: LeafInstantiable) {
-    @public val in = in
-    @public val out = out
+  class NestedInstantiable(val _in: LeafInstantiable, val _out: LeafInstantiable) extends IsInstantiable {
+    @public val in = _in
+    @public val out = _out
   }
 
   @instantiable
-  class AddOneNestedInstantiableData(width: Int) extends Module {
+  class AddOneNestedInstantiableData(width: Int) extends Module with IsInstantiable {
     @public val in = IO(Input(UInt(width.W)))
     @public val out = IO(Output(UInt(width.W)))
     out := in + 1.U
 
     @public val leafOut = new LeafInstantiable(out)
     @public val leafIn = new LeafInstantiable(in)
-    @public val nested = new NestedInstantiable(in = leafIn, out = leafOut)
+    @public val nested = new NestedInstantiable(_in = leafIn, _out = leafOut)
 
   }
   @instantiable
-  class HasUnsanitaryBundleField extends Module {
+  class HasUnsanitaryBundleField extends Module with IsInstantiable {
     class Interface extends Bundle {
       val `a-x` = UInt(8.W)
     }
@@ -330,13 +333,13 @@ object Examples {
   }
 
   @instantiable
-  class HasAnalogWire extends RawModule {
+  class HasAnalogWire extends RawModule with IsInstantiable {
     @public val port = IO(Analog(8.W))
     @public val wire = Wire(Analog(32.W))
     attach(port, wire)
   }
 
-  class AddTwoNestedInstantiableData(width: Int) extends Module {
+  class AddTwoNestedInstantiableData(width: Int) extends Module with IsInstantiable {
     val in = IO(Input(UInt(width.W)))
     val out = IO(Output(UInt(width.W)))
     val addOneDef = Definition(new AddOneNestedInstantiableData(width))
@@ -351,7 +354,9 @@ object Examples {
     i1.nested.in.bundle := i0.nested.out.bundle
   }
 
-  class AddTwoNestedInstantiableDataSubmodule(addOneDef: Definition[AddOneNestedInstantiableData]) extends Module {
+  class AddTwoNestedInstantiableDataSubmodule(addOneDef: Definition[AddOneNestedInstantiableData])
+      extends Module
+      with IsInstantiable {
     val in = IO(Input(UInt(addOneDef.in.getWidth.W)))
     val out = IO(Output(UInt(addOneDef.out.getWidth.W)))
     val i0 = Instance(addOneDef)
@@ -365,7 +370,7 @@ object Examples {
     i1.nested.in.bundle := i0.nested.out.bundle
   }
 
-  class AddTwoNestedInstantiableDataWrapper(width: Int) extends Module {
+  class AddTwoNestedInstantiableDataWrapper(width: Int) extends Module with IsInstantiable {
     val in = IO(Input(UInt(width.W)))
     val out = IO(Output(UInt(width.W)))
 
@@ -379,14 +384,14 @@ object Examples {
   }
 
   @instantiable
-  class HasPublicUnit extends Module {
+  class HasPublicUnit extends Module with IsInstantiable {
     @public val x: Unit = ()
     // Should also work in type-parameterized lookupable things
     @public val y: (Data, Unit) = (Wire(UInt(3.W)), ())
   }
 
   @instantiable
-  class HasPublicActualDirection extends Module {
+  class HasPublicActualDirection extends Module with IsInstantiable {
     val io = IO(new Bundle {
       val input = Input(UInt(8.W))
       val output = Output(UInt(8.W))
@@ -416,7 +421,7 @@ object Examples {
   }
 
   @instantiable
-  class HasUserDefinedType extends Module {
+  class HasUserDefinedType extends Module with IsInstantiable {
     val defn = Definition(new AddOne)
     val inst0: Instance[AddOne] = Instance(defn)
     val inst1: Instance[AddOne] = Instance(defn)
@@ -450,11 +455,11 @@ object Examples {
 
   // For test 9.c in DefinitionSpec - testing .toDefinition on Instance from imported Definition
   @instantiable
-  class BarForImport extends RawModule {
+  class BarForImport extends RawModule with IsInstantiable {
     @public val a = WireInit(false.B)
   }
   @instantiable
-  class FooForImport extends RawModule {
+  class FooForImport extends RawModule with IsInstantiable {
     @public val bar = Module(new BarForImport)
   }
 }
diff --git a/src/test/scala-2/chiselTests/experimental/hierarchy/InstanceSpec.scala b/src/test/scala/chiselTests/experimental/hierarchy/InstanceSpec.scala
similarity index 99%
rename from src/test/scala-2/chiselTests/experimental/hierarchy/InstanceSpec.scala
rename to src/test/scala/chiselTests/experimental/hierarchy/InstanceSpec.scala
index 5fc584c7100..de7f0ecb713 100644
--- a/src/test/scala-2/chiselTests/experimental/hierarchy/InstanceSpec.scala
+++ b/src/test/scala/chiselTests/experimental/hierarchy/InstanceSpec.scala
@@ -10,6 +10,7 @@ import chisel3.testing.scalatest.FileCheck
 import chisel3.util.{DecoupledIO, Valid}
 import chisel3.experimental.{attach, Analog}
 import chisel3.stage.{ChiselGeneratorAnnotation, DesignAnnotation}
+import firrtl.annoSeqToSeq
 import circt.stage.ChiselStage
 import org.scalatest.funspec.AnyFunSpec
 import org.scalatest.matchers.should.Matchers
@@ -639,7 +640,7 @@ class InstanceSpec extends AnyFunSpec with Matchers with Utils with FileCheck {
         @public override val overriddenVal = 12
         @public final val finalVal = 12
         @public lazy val lazyValue = 12
-        @public val value = value
+        @public override val value = value
         @public final override lazy val x: Int = 3
         @public override final lazy val y: Int = 4
       }
@@ -1317,7 +1318,9 @@ class InstanceSpec extends AnyFunSpec with Matchers with Utils with FileCheck {
       }
       ChiselStage.emitCHIRRTL(new Top)
     }
-    it("(9.b): it should not work on inner classes") {
+    // Due to the differences between ClassTag in Scala 3 and TypeTag
+    // in Scala 2, isA should work on inner classes in  Scala 3
+    ignore("(9.b): it should not work on inner classes") {
       class InnerClass extends Module
       class Top extends Module {
         val d = Definition(new InnerClass)
diff --git a/src/test/scala-2/chiselTests/experimental/hierarchy/SeparateElaborationSpec.scala b/src/test/scala/chiselTests/experimental/hierarchy/SeparateElaborationSpec.scala
similarity index 99%
rename from src/test/scala-2/chiselTests/experimental/hierarchy/SeparateElaborationSpec.scala
rename to src/test/scala/chiselTests/experimental/hierarchy/SeparateElaborationSpec.scala
index dbeec0f0298..b408e45a706 100644
--- a/src/test/scala-2/chiselTests/experimental/hierarchy/SeparateElaborationSpec.scala
+++ b/src/test/scala/chiselTests/experimental/hierarchy/SeparateElaborationSpec.scala
@@ -12,7 +12,7 @@ import chisel3.stage.{ChiselCircuitAnnotation, ChiselGeneratorAnnotation, Design
 import chisel3.testing.{FileCheck, HasTestingDirectory}
 import chisel3.testing.scalatest.TestingDirectory
 import circt.stage.{CIRCTTarget, CIRCTTargetAnnotation, ChiselStage}
-import firrtl.AnnotationSeq
+import firrtl.{annoSeqToSeq, seqToAnnoSeq, AnnotationSeq}
 import java.nio.file.Paths
 import org.scalatest.funspec.AnyFunSpec
 import org.scalatest.matchers.should.Matchers

From f1d689ba8b80b7fca65be34caa7bbce0d385734a Mon Sep 17 00:00:00 2001
From: Aditya Naik <aditya.naik@sifive.com>
Date: Tue, 26 May 2026 15:27:52 -0700
Subject: [PATCH 2/3] Remove mixin on Modules

---
 .../experimental/hierarchy/Examples.scala     | 88 +++++++++----------
 1 file changed, 44 insertions(+), 44 deletions(-)

diff --git a/src/test/scala/chiselTests/experimental/hierarchy/Examples.scala b/src/test/scala/chiselTests/experimental/hierarchy/Examples.scala
index 469bd9c38ed..d7182c50dd6 100644
--- a/src/test/scala/chiselTests/experimental/hierarchy/Examples.scala
+++ b/src/test/scala/chiselTests/experimental/hierarchy/Examples.scala
@@ -12,7 +12,7 @@ import scala.collection.immutable.SeqMap
 object Examples {
   import Annotations._
   @instantiable
-  class AddOne extends Module with IsInstantiable {
+  class AddOne extends Module {
     @public val in = IO(Input(UInt(32.W)))
     @public val out = IO(Output(UInt(32.W)))
     @public val innerWire = Wire(UInt(32.W))
@@ -20,7 +20,7 @@ object Examples {
     out := innerWire
   }
   @instantiable
-  class AddOneWithAnnotation extends Module with IsInstantiable {
+  class AddOneWithAnnotation extends Module {
     @public val in = IO(Input(UInt(32.W)))
     @public val out = IO(Output(UInt(32.W)))
     @public val innerWire = Wire(UInt(32.W))
@@ -29,7 +29,7 @@ object Examples {
     out := innerWire
   }
   @instantiable
-  class AddOneWithAbsoluteAnnotation extends Module with IsInstantiable {
+  class AddOneWithAbsoluteAnnotation extends Module {
     @public val in = IO(Input(UInt(32.W)))
     @public val out = IO(Output(UInt(32.W)))
     @public val innerWire = Wire(UInt(32.W))
@@ -38,12 +38,12 @@ object Examples {
     out := innerWire
   }
   @instantiable
-  class AddOneParameterized(width: Int) extends Module with IsInstantiable {
+  class AddOneParameterized(width: Int) extends Module {
     @public val in = IO(Input(UInt(width.W)))
     @public val out = IO(Output(UInt(width.W)))
     out := in + 1.U
   }
-  class AddOneWithNested(width: Int) extends Module with IsInstantiable {
+  class AddOneWithNested(width: Int) extends Module {
     @public val in = IO(Input(UInt(width.W)))
     @public val out = IO(Output(UInt(width.W)))
     val addOneDef = Seq.fill(3)(Definition(new AddOne))
@@ -58,7 +58,7 @@ object Examples {
   }
 
   @instantiable
-  class AddTwo extends Module with IsInstantiable {
+  class AddTwo extends Module {
     @public val in = IO(Input(UInt(32.W)))
     @public val out = IO(Output(UInt(32.W)))
     @public val definition = Definition(new AddOne)
@@ -69,7 +69,7 @@ object Examples {
     out := i1.out
   }
   @instantiable
-  class AddTwoMixedModules extends Module with IsInstantiable {
+  class AddTwoMixedModules extends Module {
     @public val in = IO(Input(UInt(32.W)))
     @public val out = IO(Output(UInt(32.W)))
     val definition = Definition(new AddOne)
@@ -82,7 +82,7 @@ object Examples {
   @instantiable
   class AddTwoParameterized(width: Int, makeParameterizedOnes: Int => Seq[Instance[AddOneParameterized]])
       extends Module
-      with IsInstantiable {
+       {
     val in = IO(Input(UInt(width.W)))
     val out = IO(Output(UInt(width.W)))
     val addOnes = makeParameterizedOnes(width)
@@ -93,13 +93,13 @@ object Examples {
   @instantiable
   class AddTwoWithNested(width: Int, makeParameterizedOnes: Int => Seq[Instance[AddOneWithNested]])
       extends Module
-      with IsInstantiable {
+       {
     val in = IO(Input(UInt(width.W)))
     val out = IO(Output(UInt(width.W)))
     val addOnes = makeParameterizedOnes(width)
   }
   @instantiable
-  class AddTwoDefinitionArgument(definition: Definition[AddOne]) extends Module with IsInstantiable {
+  class AddTwoDefinitionArgument(definition: Definition[AddOne]) extends Module {
     @public val in = IO(Input(UInt(32.W)))
     @public val out = IO(Output(UInt(32.W)))
     @public val i0: Instance[AddOne] = Instance(definition)
@@ -110,7 +110,7 @@ object Examples {
   }
 
   @instantiable
-  class AddFour extends Module with IsInstantiable {
+  class AddFour extends Module {
     @public val in = IO(Input(UInt(32.W)))
     @public val out = IO(Output(UInt(32.W)))
     @public val definition = Definition(new AddTwoMixedModules)
@@ -121,7 +121,7 @@ object Examples {
     out := i1.out
   }
   @instantiable
-  class AggregatePortModule extends Module with IsInstantiable {
+  class AggregatePortModule extends Module {
     @public val io = IO(new Bundle {
       val in = Input(UInt(32.W))
       val out = Output(UInt(32.W))
@@ -133,7 +133,7 @@ object Examples {
     @public val innerWire = Wire(UInt(32.W))
   }
   @instantiable
-  class AddOneWithInstantiableWire extends Module with IsInstantiable {
+  class AddOneWithInstantiableWire extends Module {
     @public val in = IO(Input(UInt(32.W)))
     @public val out = IO(Output(UInt(32.W)))
     @public val wireContainer = new WireContainer()
@@ -145,7 +145,7 @@ object Examples {
     @public val i0 = Module(new AddOne)
   }
   @instantiable
-  class AddOneWithInstantiableModule extends Module with IsInstantiable {
+  class AddOneWithInstantiableModule extends Module {
     @public val in = IO(Input(UInt(32.W)))
     @public val out = IO(Output(UInt(32.W)))
     @public val moduleContainer = new AddOneContainer()
@@ -158,7 +158,7 @@ object Examples {
     @public val i0 = Instance(definition)
   }
   @instantiable
-  class AddOneWithInstantiableInstance extends Module with IsInstantiable {
+  class AddOneWithInstantiableInstance extends Module {
     @public val in = IO(Input(UInt(32.W)))
     @public val out = IO(Output(UInt(32.W)))
     @public val instanceContainer = new AddOneInstanceContainer()
@@ -170,7 +170,7 @@ object Examples {
     @public val container = new AddOneContainer
   }
   @instantiable
-  class AddOneWithInstantiableInstantiable extends Module with IsInstantiable {
+  class AddOneWithInstantiableInstantiable extends Module {
     @public val in = IO(Input(UInt(32.W)))
     @public val out = IO(Output(UInt(32.W)))
     @public val containerContainer = new AddOneContainerContainer()
@@ -183,7 +183,7 @@ object Examples {
     if (markPlease) mark(x.i0.innerWire, "first")
   }
   @instantiable
-  class ViewerParent(val x: AddTwo, markHere: Boolean, markThere: Boolean) extends Module with IsInstantiable {
+  class ViewerParent(val x: AddTwo, markHere: Boolean, markThere: Boolean) extends Module {
     @public val viewer = new Viewer(x, markThere)
     if (markHere) mark(viewer.x.i0.innerWire, "second")
   }
@@ -192,7 +192,7 @@ object Examples {
     @public val (x, y) = (Wire(UInt(3.W)), Wire(UInt(3.W)))
   }
   @instantiable
-  class LazyVal() extends Module with IsInstantiable {
+  class LazyVal() extends Module {
     @public val x = Wire(UInt(3.W))
     @public lazy val y = "Hi"
   }
@@ -203,73 +203,73 @@ object Examples {
     @public val x = Wire(UInt(3.W))
   }
   @instantiable
-  class HasList() extends Module with IsInstantiable {
+  class HasList() extends Module  {
     @public val y = List(1, 2, 3)
     @public val x = List.fill(3)(Wire(UInt(3.W)))
   }
   @instantiable
-  class HasSeq() extends Module with IsInstantiable {
+  class HasSeq() extends Module  {
     @public val y = Seq(1, 2, 3)
     @public val x = Seq.fill(3)(Wire(UInt(3.W)))
   }
   @instantiable
-  class HasOption() extends Module with IsInstantiable {
+  class HasOption() extends Module  {
     @public val x: Option[UInt] = Some(Wire(UInt(3.W)))
   }
   @instantiable
-  class HasEither() extends Module with IsInstantiable {
+  class HasEither() extends Module  {
     @public val x: Either[Bool, UInt] = Right(Wire(UInt(3.W)).suggestName("x"))
     @public val y: Either[Bool, UInt] = Left(Wire(Bool()).suggestName("y"))
   }
   @instantiable
-  class HasTuple2() extends Module with IsInstantiable {
+  class HasTuple2() extends Module  {
     val x = Wire(UInt(3.W))
     val y = Wire(Bool())
     @public val xy = (x, y)
   }
   @instantiable
-  class HasTuple5() extends Module with IsInstantiable {
+  class HasTuple5() extends Module  {
     val wire = Wire(UInt(3.W))
     val inst = Module(new AddOne)
     @public val tup = (3, wire, "hi", inst, List(1, 2, 3))
   }
   @instantiable
-  class HasHasTarget() extends Module with IsInstantiable {
+  class HasHasTarget() extends Module  {
     val sram = SRAM(1024, UInt(8.W), 1, 1, 0)
     @public val x: HasTarget = sram.underlying.get
   }
   @instantiable
-  class HasVec() extends Module with IsInstantiable {
+  class HasVec() extends Module  {
     @public val x = VecInit(1.U, 2.U, 3.U)
   }
   @instantiable
-  class HasIndexedVec() extends Module with IsInstantiable {
+  class HasIndexedVec() extends Module  {
     val x = VecInit(1.U, 2.U, 3.U)
     @public val y = x(1)
   }
   @instantiable
-  class HasSubFieldAccess extends Module with IsInstantiable {
+  class HasSubFieldAccess extends Module  {
     val in = IO(Input(Valid(UInt(8.W))))
     @public val valid = in.valid
     @public val bits = in.bits
   }
   @instantiable
-  class HasPublicConstructorArgs(@public val int: Int) extends Module with IsInstantiable {
+  class HasPublicConstructorArgs(@public val int: Int) extends Module  {
     @public val x = Wire(UInt(3.W))
   }
   @instantiable
-  class InstantiatesHasVec() extends Module with IsInstantiable {
+  class InstantiatesHasVec() extends Module  {
     @public val i0 = Instance(Definition(new HasVec()))
     @public val i1 = Module(new HasVec())
   }
   @instantiable
-  class HasUninferredReset() extends Module with IsInstantiable {
+  class HasUninferredReset() extends Module  {
     @public val in = IO(Input(UInt(3.W)))
     @public val out = IO(Output(UInt(3.W)))
     out := RegNext(in)
   }
   @instantiable
-  abstract class HasBlah() extends Module with IsInstantiable {
+  abstract class HasBlah() extends Module  {
     @public val blah: Int
   }
 
@@ -278,12 +278,12 @@ object Examples {
     val blah = 10
   }
   @instantiable
-  class HasTypeParams[D <: Data](d: D) extends Module with IsInstantiable {
+  class HasTypeParams[D <: Data](d: D) extends Module  {
     @public val blah = Wire(d)
   }
 
   @instantiable
-  class HasMultipleTypeParamsInside extends Module with IsInstantiable {
+  class HasMultipleTypeParamsInside extends Module  {
     val tpDef0 = Definition(new HasTypeParams(Bool()))
     val tpDef1 = Definition(new HasTypeParams(UInt(4.W)))
     val i00 = Instance(tpDef0)
@@ -293,7 +293,7 @@ object Examples {
   }
 
   @instantiable
-  class HasMems() extends Module with IsInstantiable {
+  class HasMems() extends Module  {
     @public val mem = Mem(8, UInt(32.W))
     @public val syncReadMem = SyncReadMem(8, UInt(32.W))
   }
@@ -310,7 +310,7 @@ object Examples {
   }
 
   @instantiable
-  class AddOneNestedInstantiableData(width: Int) extends Module with IsInstantiable {
+  class AddOneNestedInstantiableData(width: Int) extends Module  {
     @public val in = IO(Input(UInt(width.W)))
     @public val out = IO(Output(UInt(width.W)))
     out := in + 1.U
@@ -321,7 +321,7 @@ object Examples {
 
   }
   @instantiable
-  class HasUnsanitaryBundleField extends Module with IsInstantiable {
+  class HasUnsanitaryBundleField extends Module  {
     class Interface extends Bundle {
       val `a-x` = UInt(8.W)
     }
@@ -333,13 +333,13 @@ object Examples {
   }
 
   @instantiable
-  class HasAnalogWire extends RawModule with IsInstantiable {
+  class HasAnalogWire extends RawModule  {
     @public val port = IO(Analog(8.W))
     @public val wire = Wire(Analog(32.W))
     attach(port, wire)
   }
 
-  class AddTwoNestedInstantiableData(width: Int) extends Module with IsInstantiable {
+  class AddTwoNestedInstantiableData(width: Int) extends Module  {
     val in = IO(Input(UInt(width.W)))
     val out = IO(Output(UInt(width.W)))
     val addOneDef = Definition(new AddOneNestedInstantiableData(width))
@@ -356,7 +356,7 @@ object Examples {
 
   class AddTwoNestedInstantiableDataSubmodule(addOneDef: Definition[AddOneNestedInstantiableData])
       extends Module
-      with IsInstantiable {
+       {
     val in = IO(Input(UInt(addOneDef.in.getWidth.W)))
     val out = IO(Output(UInt(addOneDef.out.getWidth.W)))
     val i0 = Instance(addOneDef)
@@ -370,7 +370,7 @@ object Examples {
     i1.nested.in.bundle := i0.nested.out.bundle
   }
 
-  class AddTwoNestedInstantiableDataWrapper(width: Int) extends Module with IsInstantiable {
+  class AddTwoNestedInstantiableDataWrapper(width: Int) extends Module  {
     val in = IO(Input(UInt(width.W)))
     val out = IO(Output(UInt(width.W)))
 
@@ -384,14 +384,14 @@ object Examples {
   }
 
   @instantiable
-  class HasPublicUnit extends Module with IsInstantiable {
+  class HasPublicUnit extends Module  {
     @public val x: Unit = ()
     // Should also work in type-parameterized lookupable things
     @public val y: (Data, Unit) = (Wire(UInt(3.W)), ())
   }
 
   @instantiable
-  class HasPublicActualDirection extends Module with IsInstantiable {
+  class HasPublicActualDirection extends Module  {
     val io = IO(new Bundle {
       val input = Input(UInt(8.W))
       val output = Output(UInt(8.W))
@@ -421,7 +421,7 @@ object Examples {
   }
 
   @instantiable
-  class HasUserDefinedType extends Module with IsInstantiable {
+  class HasUserDefinedType extends Module  {
     val defn = Definition(new AddOne)
     val inst0: Instance[AddOne] = Instance(defn)
     val inst1: Instance[AddOne] = Instance(defn)

From 0e207460fef2fc7a8f3fbd6e50bb6e7fedf5e9e5 Mon Sep 17 00:00:00 2001
From: Aditya Naik <aditya.naik@sifive.com>
Date: Tue, 26 May 2026 15:29:10 -0700
Subject: [PATCH 3/3] Formatting

---
 .../experimental/hierarchy/Examples.scala     | 61 +++++++++----------
 1 file changed, 28 insertions(+), 33 deletions(-)

diff --git a/src/test/scala/chiselTests/experimental/hierarchy/Examples.scala b/src/test/scala/chiselTests/experimental/hierarchy/Examples.scala
index d7182c50dd6..ca9fb6e5f6e 100644
--- a/src/test/scala/chiselTests/experimental/hierarchy/Examples.scala
+++ b/src/test/scala/chiselTests/experimental/hierarchy/Examples.scala
@@ -81,8 +81,7 @@ object Examples {
   }
   @instantiable
   class AddTwoParameterized(width: Int, makeParameterizedOnes: Int => Seq[Instance[AddOneParameterized]])
-      extends Module
-       {
+      extends Module {
     val in = IO(Input(UInt(width.W)))
     val out = IO(Output(UInt(width.W)))
     val addOnes = makeParameterizedOnes(width)
@@ -91,9 +90,7 @@ object Examples {
     addOnes.zip(addOnes.tail).foreach { case (head, tail) => tail.in := head.out }
   }
   @instantiable
-  class AddTwoWithNested(width: Int, makeParameterizedOnes: Int => Seq[Instance[AddOneWithNested]])
-      extends Module
-       {
+  class AddTwoWithNested(width: Int, makeParameterizedOnes: Int => Seq[Instance[AddOneWithNested]]) extends Module {
     val in = IO(Input(UInt(width.W)))
     val out = IO(Output(UInt(width.W)))
     val addOnes = makeParameterizedOnes(width)
@@ -203,73 +200,73 @@ object Examples {
     @public val x = Wire(UInt(3.W))
   }
   @instantiable
-  class HasList() extends Module  {
+  class HasList() extends Module {
     @public val y = List(1, 2, 3)
     @public val x = List.fill(3)(Wire(UInt(3.W)))
   }
   @instantiable
-  class HasSeq() extends Module  {
+  class HasSeq() extends Module {
     @public val y = Seq(1, 2, 3)
     @public val x = Seq.fill(3)(Wire(UInt(3.W)))
   }
   @instantiable
-  class HasOption() extends Module  {
+  class HasOption() extends Module {
     @public val x: Option[UInt] = Some(Wire(UInt(3.W)))
   }
   @instantiable
-  class HasEither() extends Module  {
+  class HasEither() extends Module {
     @public val x: Either[Bool, UInt] = Right(Wire(UInt(3.W)).suggestName("x"))
     @public val y: Either[Bool, UInt] = Left(Wire(Bool()).suggestName("y"))
   }
   @instantiable
-  class HasTuple2() extends Module  {
+  class HasTuple2() extends Module {
     val x = Wire(UInt(3.W))
     val y = Wire(Bool())
     @public val xy = (x, y)
   }
   @instantiable
-  class HasTuple5() extends Module  {
+  class HasTuple5() extends Module {
     val wire = Wire(UInt(3.W))
     val inst = Module(new AddOne)
     @public val tup = (3, wire, "hi", inst, List(1, 2, 3))
   }
   @instantiable
-  class HasHasTarget() extends Module  {
+  class HasHasTarget() extends Module {
     val sram = SRAM(1024, UInt(8.W), 1, 1, 0)
     @public val x: HasTarget = sram.underlying.get
   }
   @instantiable
-  class HasVec() extends Module  {
+  class HasVec() extends Module {
     @public val x = VecInit(1.U, 2.U, 3.U)
   }
   @instantiable
-  class HasIndexedVec() extends Module  {
+  class HasIndexedVec() extends Module {
     val x = VecInit(1.U, 2.U, 3.U)
     @public val y = x(1)
   }
   @instantiable
-  class HasSubFieldAccess extends Module  {
+  class HasSubFieldAccess extends Module {
     val in = IO(Input(Valid(UInt(8.W))))
     @public val valid = in.valid
     @public val bits = in.bits
   }
   @instantiable
-  class HasPublicConstructorArgs(@public val int: Int) extends Module  {
+  class HasPublicConstructorArgs(@public val int: Int) extends Module {
     @public val x = Wire(UInt(3.W))
   }
   @instantiable
-  class InstantiatesHasVec() extends Module  {
+  class InstantiatesHasVec() extends Module {
     @public val i0 = Instance(Definition(new HasVec()))
     @public val i1 = Module(new HasVec())
   }
   @instantiable
-  class HasUninferredReset() extends Module  {
+  class HasUninferredReset() extends Module {
     @public val in = IO(Input(UInt(3.W)))
     @public val out = IO(Output(UInt(3.W)))
     out := RegNext(in)
   }
   @instantiable
-  abstract class HasBlah() extends Module  {
+  abstract class HasBlah() extends Module {
     @public val blah: Int
   }
 
@@ -278,12 +275,12 @@ object Examples {
     val blah = 10
   }
   @instantiable
-  class HasTypeParams[D <: Data](d: D) extends Module  {
+  class HasTypeParams[D <: Data](d: D) extends Module {
     @public val blah = Wire(d)
   }
 
   @instantiable
-  class HasMultipleTypeParamsInside extends Module  {
+  class HasMultipleTypeParamsInside extends Module {
     val tpDef0 = Definition(new HasTypeParams(Bool()))
     val tpDef1 = Definition(new HasTypeParams(UInt(4.W)))
     val i00 = Instance(tpDef0)
@@ -293,7 +290,7 @@ object Examples {
   }
 
   @instantiable
-  class HasMems() extends Module  {
+  class HasMems() extends Module {
     @public val mem = Mem(8, UInt(32.W))
     @public val syncReadMem = SyncReadMem(8, UInt(32.W))
   }
@@ -310,7 +307,7 @@ object Examples {
   }
 
   @instantiable
-  class AddOneNestedInstantiableData(width: Int) extends Module  {
+  class AddOneNestedInstantiableData(width: Int) extends Module {
     @public val in = IO(Input(UInt(width.W)))
     @public val out = IO(Output(UInt(width.W)))
     out := in + 1.U
@@ -321,7 +318,7 @@ object Examples {
 
   }
   @instantiable
-  class HasUnsanitaryBundleField extends Module  {
+  class HasUnsanitaryBundleField extends Module {
     class Interface extends Bundle {
       val `a-x` = UInt(8.W)
     }
@@ -333,13 +330,13 @@ object Examples {
   }
 
   @instantiable
-  class HasAnalogWire extends RawModule  {
+  class HasAnalogWire extends RawModule {
     @public val port = IO(Analog(8.W))
     @public val wire = Wire(Analog(32.W))
     attach(port, wire)
   }
 
-  class AddTwoNestedInstantiableData(width: Int) extends Module  {
+  class AddTwoNestedInstantiableData(width: Int) extends Module {
     val in = IO(Input(UInt(width.W)))
     val out = IO(Output(UInt(width.W)))
     val addOneDef = Definition(new AddOneNestedInstantiableData(width))
@@ -354,9 +351,7 @@ object Examples {
     i1.nested.in.bundle := i0.nested.out.bundle
   }
 
-  class AddTwoNestedInstantiableDataSubmodule(addOneDef: Definition[AddOneNestedInstantiableData])
-      extends Module
-       {
+  class AddTwoNestedInstantiableDataSubmodule(addOneDef: Definition[AddOneNestedInstantiableData]) extends Module {
     val in = IO(Input(UInt(addOneDef.in.getWidth.W)))
     val out = IO(Output(UInt(addOneDef.out.getWidth.W)))
     val i0 = Instance(addOneDef)
@@ -370,7 +365,7 @@ object Examples {
     i1.nested.in.bundle := i0.nested.out.bundle
   }
 
-  class AddTwoNestedInstantiableDataWrapper(width: Int) extends Module  {
+  class AddTwoNestedInstantiableDataWrapper(width: Int) extends Module {
     val in = IO(Input(UInt(width.W)))
     val out = IO(Output(UInt(width.W)))
 
@@ -384,14 +379,14 @@ object Examples {
   }
 
   @instantiable
-  class HasPublicUnit extends Module  {
+  class HasPublicUnit extends Module {
     @public val x: Unit = ()
     // Should also work in type-parameterized lookupable things
     @public val y: (Data, Unit) = (Wire(UInt(3.W)), ())
   }
 
   @instantiable
-  class HasPublicActualDirection extends Module  {
+  class HasPublicActualDirection extends Module {
     val io = IO(new Bundle {
       val input = Input(UInt(8.W))
       val output = Output(UInt(8.W))
@@ -421,7 +416,7 @@ object Examples {
   }
 
   @instantiable
-  class HasUserDefinedType extends Module  {
+  class HasUserDefinedType extends Module {
     val defn = Definition(new AddOne)
     val inst0: Instance[AddOne] = Instance(defn)
     val inst1: Instance[AddOne] = Instance(defn)