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diff --git a/core/src/main/scala/chisel3/internal/package.scala b/core/src/main/scala/chisel3/internal/package.scala
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+// SPDX-License-Identifier: Apache-2.0
+
+package chisel3
+
+import firrtl.annotations.{IsModule, ModuleTarget}
+import chisel3.experimental.BaseModule
+import chisel3.internal.firrtl.{Component, DefModule} // TODO move to object ir
+import chisel3.internal.Builder.Prefix
+import chisel3.ChiselException
+
+import scala.util.Try
+import scala.annotation.implicitNotFound
+import scala.collection.mutable
+import scala.quoted
+import scala.quoted._
+
+package object internal {
+
+  /** Marker trait for modules that are not true modules */
+  private[chisel3] trait PseudoModule extends BaseModule
+
+  /* Check if a String name is a temporary name */
+  def isTemp(name: String): Boolean = name.nonEmpty && name.head == '_'
+
+  /** Creates a name String from a prefix and a seed
+    * @param prefix The prefix associated with the seed (must be in correct order, *not* reversed)
+    * @param seed The seed for computing the name (if available)
+    */
+  def buildName(seed: String, prefix: Prefix): String = {
+    // Don't bother copying the String if there's no prefix
+    if (prefix.isEmpty) {
+      seed
+    } else {
+      // Using Java's String builder to micro-optimize appending a String excluding 1st character
+      // for temporaries
+      val builder = new java.lang.StringBuilder()
+      // Starting with _ is the indicator of a temporary
+      val temp = isTemp(seed)
+      // Make sure the final result is also a temporary if this is a temporary
+      if (temp) {
+        builder.append('_')
+      }
+      prefix.foreach { p =>
+        builder.append(p)
+        builder.append('_')
+      }
+      if (temp) {
+        // We've moved the leading _ to the front, drop it here
+        builder.append(seed, 1, seed.length)
+      } else {
+        builder.append(seed)
+      }
+      builder.toString
+    }
+  }
+
+  // Sanitizes a name, e.g. from a `HasId`, by stripping all non ANSI-C characters
+  private[chisel3] def sanitize(s: String, leadingDigitOk: Boolean = false): String = {
+    // TODO what character set does FIRRTL truly support? using ANSI C for now
+    def legalStart(c: Char) = (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z') || c == '_'
+    def legal(c:      Char) = legalStart(c) || (c >= '0' && c <= '9')
+    val res = if (s.forall(legal)) s else s.filter(legal)
+    val headOk = (!res.isEmpty) && (leadingDigitOk || legalStart(res.head))
+    if (headOk) res else s"_$res"
+  }
+
+  // Workaround for https://github.com/chipsalliance/chisel/issues/4162
+  // We can't use the .asTypeOf workaround because this is used to implement .asTypeOf
+  private[chisel3] def _padHandleBool[A <: Bits](
+    x:     A,
+    width: Int
+  )(using Quotes): A = x match {
+    case b: Bool if !b.isLit && width > 1 && Type.of[A] == Type.of[UInt] =>
+      val _pad = Wire(UInt(width.W))
+      _pad := b
+      _pad.asInstanceOf[A] // This cast is safe because we know A is UInt on this path
+    case u => u.pad(width)
+  }
+
+  // Resize that to this width (if known)
+  // TODO fix the "take not member of A"  error here
+  // private[chisel3] def _resizeToWidth[A <: Bits](
+  //   that:           A,
+  //   targetWidthOpt: Option[Int]
+  // )(fromUInt:       UInt => A
+  // )(using Quotes): A =
+  //   (targetWidthOpt, that.widthOption) match {
+  //     case (Some(targetWidth), Some(thatWidth)) =>
+  //       if (targetWidth == thatWidth) that
+  //       else if (targetWidth > thatWidth) _padHandleBool(that, targetWidth)
+  //       else fromUInt(that.take(targetWidth))
+  //     case (Some(targetWidth), None) => fromUInt(_padHandleBool(that, targetWidth).take(targetWidth))
+  //     case (None, Some(thatWidth))   => that
+  //     case (None, None)              => that
+  //   }
+
+  /** Internal API for [[ViewParent]] */
+  sealed private[chisel3] class ViewParentAPI extends RawModule() with PseudoModule {
+    // We must provide `absoluteTarget` but not `toTarget` because otherwise they would be exactly
+    // the same and we'd have no way to distinguish the kind of target when renaming view targets in
+    // the Converter
+    // Note that this is not overriding .toAbsoluteTarget, that is a final def in BaseModule that delegates
+    // to this method
+    private[chisel3] val absoluteTarget: IsModule = ModuleTarget(this.circuitName, "_$$AbsoluteView$$_")
+
+    // This module is not instantiable
+    override private[chisel3] def generateComponent():  Option[Component] = None
+    override private[chisel3] def initializeInParent(): Unit = ()
+    // This module is not really part of the circuit
+    _parent = None
+
+    // Sigil to mark views, starts with '_' to make it a legal FIRRTL target
+    override def desiredName = "_$$View$$_"
+
+    private[chisel3] val fakeComponent: Component = DefModule(this, desiredName, Nil, Nil)
+  }
+
+  /** Special internal object representing the parent of all views
+    *
+    * @note this is a val instead of an object because of the need to wrap in Module(...)
+    * @note this is a lazy val so that calling functions in this package object doesn't create it
+    */
+  private[chisel3] lazy val ViewParent =
+    Module.apply(new ViewParentAPI)
+
+
+  // TODO this exists in cats.Traverse, should we just use that?
+  private[chisel3] implicit class ListSyntax[A](xs: List[A]) {
+    def mapAccumulate[B, C](z: B)(f: (B, A) => (B, C)): (B, List[C]) = {
+      val (zz, result) = xs.foldLeft((z, List.empty[C])) {
+        case ((acc, res), a) =>
+          val (accx, c) = f(acc, a)
+          (accx, c :: res)
+      }
+      (zz, result.reverse)
+    }
+  }
+
+  /** This is effectively a "LazyVal" box type, we can create the object but delay executing the argument
+    *
+    * @note This is similar to cats.Eval.later but we don't depend on Cats
+    */
+  private[chisel3] class Delayed[A](a: => A) {
+    lazy val value: A = a
+  }
+  private[chisel3] object Delayed {
+    def apply[A](a: => A): Delayed[A] = new Delayed(a)
+  }
+
+  /** The list of banned type alias words which will cause generation of bad FIRRTL. These are usually
+    * keyword tokens that would be automatically lexed by firtool, and so cause parsing errors.
+    */
+  private[chisel3] val illegalTypeAliases = Seq(
+    "FIRRTL",
+    "Clock",
+    "UInt",
+    "Reset",
+    "AsyncReset",
+    "Analog",
+    "Probe",
+    "RWProbe",
+    "version",
+    "type",
+    "circuit",
+    "parameter",
+    "input",
+    "output",
+    "extmodule",
+    "module",
+    "intmodule",
+    "intrinsic",
+    "defname",
+    "const",
+    "flip",
+    "reg",
+    "smem",
+    "cmem",
+    "mport",
+    "define",
+    "attach",
+    "inst",
+    "of",
+    "reset",
+    "printf",
+    "skip",
+    "node"
+  )
+
+  /** Similar to Seq.groupBy except that it preserves ordering of elements within each group */
+  private[chisel3] def groupByIntoSeq[A, K](xs: Iterable[A])(f: A => K): Seq[(K, Seq[A])] = {
+    val map = mutable.LinkedHashMap.empty[K, mutable.ListBuffer[A]]
+    for (x <- xs) {
+      val key = f(x)
+      val l = map.getOrElseUpdate(key, mutable.ListBuffer.empty[A])
+      l += x
+    }
+    map.view.map({ case (k, vs) => k -> vs.toList }).toList
+  }
+}