Promote ChiselEnum user APIs from experimental (backport #2929) (#2931)

* Promote ChiselEnum user APIs from experimental (#2929)

They are commonly used and if we were ever to change them, we will need
to go through a deprecation process anyway.

Note that the EnumAnnotations remain in chisel3.experimental because,
like all Chisel annotation support, they are slated to be deprecated and
removed.

(cherry picked from commit 424e9446f1675fe0168e22bdfbbe85db997376e6)

# Conflicts:
#	docs/src/cookbooks/verilog-vs-chisel.md
#	docs/src/explanations/chisel-enum.md

* Maintain binary compatbility, use aliases in chisel3 package

* Deprecate the actual classes in chisel3.experimental
* Also fix backport conflicts

Co-authored-by: Jack Koenig <koenig@sifive.com>

1 files changed, 0 insertions, 466 deletions

diff --git a/core/src/main/scala/chisel3/StrongEnum.scala b/core/src/main/scala/chisel3/StrongEnum.scala
deleted file mode 100644
index c1967949..00000000
--- a/core/src/main/scala/chisel3/StrongEnum.scala
+++ /dev/null
@@ -1,466 +0,0 @@
-// SPDX-License-Identifier: Apache-2.0
-
-package chisel3.experimental
-
-import scala.language.experimental.macros
-import scala.reflect.macros.blackbox.Context
-import scala.collection.mutable
-import chisel3._
-import chisel3.internal.Builder.pushOp
-import chisel3.internal.firrtl.PrimOp._
-import chisel3.internal.firrtl._
-import chisel3.internal.sourceinfo._
-import chisel3.internal.{throwException, Binding, Builder, ChildBinding, ConstrainedBinding, InstanceId}
-import firrtl.annotations._
-
-object EnumAnnotations {
-
-  /** An annotation for strong enum instances that are ''not'' inside of Vecs
-    *
-    * @param target the enum instance being annotated
-    * @param enumTypeName the name of the enum's type (e.g. ''"mypackage.MyEnum"'')
-    */
-  case class EnumComponentAnnotation(target: Named, enumTypeName: String) extends SingleTargetAnnotation[Named] {
-    def duplicate(n: Named): EnumComponentAnnotation = this.copy(target = n)
-  }
-
-  case class EnumComponentChiselAnnotation(target: InstanceId, enumTypeName: String) extends ChiselAnnotation {
-    def toFirrtl: EnumComponentAnnotation = EnumComponentAnnotation(target.toNamed, enumTypeName)
-  }
-
-  /** An annotation for Vecs of strong enums.
-    *
-    * The ''fields'' parameter deserves special attention, since it may be difficult to understand. Suppose you create a the following Vec:
-    *
-    *               {{{
-    *               VecInit(new Bundle {
-    *                 val e = MyEnum()
-    *                 val b = new Bundle {
-    *                   val inner_e = MyEnum()
-    *                 }
-    *                 val v = Vec(3, MyEnum())
-    *               }
-    *               }}}
-    *
-    *               Then, the ''fields'' parameter will be: ''Seq(Seq("e"), Seq("b", "inner_e"), Seq("v"))''. Note that for any Vec that doesn't contain Bundles, this field will simply be an empty Seq.
-    *
-    * @param target the Vec being annotated
-    * @param typeName the name of the enum's type (e.g. ''"mypackage.MyEnum"'')
-    * @param fields a list of all chains of elements leading from the Vec instance to its inner enum fields.
-    */
-  case class EnumVecAnnotation(target: Named, typeName: String, fields: Seq[Seq[String]])
-      extends SingleTargetAnnotation[Named] {
-    def duplicate(n: Named): EnumVecAnnotation = this.copy(target = n)
-  }
-
-  case class EnumVecChiselAnnotation(target: InstanceId, typeName: String, fields: Seq[Seq[String]])
-      extends ChiselAnnotation {
-    override def toFirrtl: EnumVecAnnotation = EnumVecAnnotation(target.toNamed, typeName, fields)
-  }
-
-  /** An annotation for enum types (rather than enum ''instances'').
-    *
-    * @param typeName the name of the enum's type (e.g. ''"mypackage.MyEnum"'')
-    * @param definition a map describing which integer values correspond to which enum names
-    */
-  case class EnumDefAnnotation(typeName: String, definition: Map[String, BigInt]) extends NoTargetAnnotation
-
-  case class EnumDefChiselAnnotation(typeName: String, definition: Map[String, BigInt]) extends ChiselAnnotation {
-    override def toFirrtl: Annotation = EnumDefAnnotation(typeName, definition)
-  }
-}
-import EnumAnnotations._
-
-abstract class EnumType(private[chisel3] val factory: EnumFactory, selfAnnotating: Boolean = true) extends Element {
-
-  // Use getSimpleName instead of enumTypeName because for debugging purposes
-  //   the fully qualified name isn't necessary (compared to for the
-  //  Enum annotation), and it's more consistent with Bundle printing.
-  override def toString: String = {
-    litOption match {
-      case Some(value) =>
-        factory.nameOfValue(value) match {
-          case Some(name) => s"${factory.getClass.getSimpleName.init}($value=$name)"
-          case None       => stringAccessor(s"${factory.getClass.getSimpleName.init}($value=(invalid))")
-        }
-      case _ => stringAccessor(s"${factory.getClass.getSimpleName.init}")
-    }
-  }
-
-  override def cloneType: this.type = factory().asInstanceOf[this.type]
-
-  private[chisel3] def compop(sourceInfo: SourceInfo, op: PrimOp, other: EnumType): Bool = {
-    requireIsHardware(this, "bits operated on")
-    requireIsHardware(other, "bits operated on")
-
-    if (!this.typeEquivalent(other)) {
-      throwException(s"Enum types are not equivalent: ${this.enumTypeName}, ${other.enumTypeName}")
-    }
-
-    pushOp(DefPrim(sourceInfo, Bool(), op, this.ref, other.ref))
-  }
-
-  private[chisel3] override def typeEquivalent(that: Data): Boolean = {
-    this.getClass == that.getClass &&
-    this.factory == that.asInstanceOf[EnumType].factory
-  }
-
-  private[chisel3] override def connectFromBits(
-    that: Bits
-  )(
-    implicit sourceInfo: SourceInfo,
-    compileOptions:      CompileOptions
-  ): Unit = {
-    this := factory.apply(that.asUInt)
-  }
-
-  final def ===(that: EnumType): Bool = macro SourceInfoTransform.thatArg
-  final def =/=(that: EnumType): Bool = macro SourceInfoTransform.thatArg
-  final def <(that:   EnumType): Bool = macro SourceInfoTransform.thatArg
-  final def <=(that:  EnumType): Bool = macro SourceInfoTransform.thatArg
-  final def >(that:   EnumType): Bool = macro SourceInfoTransform.thatArg
-  final def >=(that:  EnumType): Bool = macro SourceInfoTransform.thatArg
-
-  def do_===(that: EnumType)(implicit sourceInfo: SourceInfo, compileOptions: CompileOptions): Bool =
-    compop(sourceInfo, EqualOp, that)
-  def do_=/=(that: EnumType)(implicit sourceInfo: SourceInfo, compileOptions: CompileOptions): Bool =
-    compop(sourceInfo, NotEqualOp, that)
-  def do_<(that: EnumType)(implicit sourceInfo: SourceInfo, compileOptions: CompileOptions): Bool =
-    compop(sourceInfo, LessOp, that)
-  def do_>(that: EnumType)(implicit sourceInfo: SourceInfo, compileOptions: CompileOptions): Bool =
-    compop(sourceInfo, GreaterOp, that)
-  def do_<=(that: EnumType)(implicit sourceInfo: SourceInfo, compileOptions: CompileOptions): Bool =
-    compop(sourceInfo, LessEqOp, that)
-  def do_>=(that: EnumType)(implicit sourceInfo: SourceInfo, compileOptions: CompileOptions): Bool =
-    compop(sourceInfo, GreaterEqOp, that)
-
-  override def do_asUInt(implicit sourceInfo: SourceInfo, compileOptions: CompileOptions): UInt =
-    pushOp(DefPrim(sourceInfo, UInt(width), AsUIntOp, ref))
-
-  protected[chisel3] override def width: Width = factory.width
-
-  def isValid(implicit sourceInfo: SourceInfo, compileOptions: CompileOptions): Bool = {
-    if (litOption.isDefined) {
-      true.B
-    } else {
-      if (factory.isTotal) true.B else factory.all.map(this === _).reduce(_ || _)
-    }
-  }
-
-  /** Test if this enumeration is equal to any of the values in a given sequence
-    *
-    * @param s a [[scala.collection.Seq$ Seq]] of enumeration values to look for
-    * @return a hardware [[Bool]] that indicates if this value matches any of the given values
-    */
-  final def isOneOf(s: Seq[EnumType])(implicit sourceInfo: SourceInfo, compileOptions: CompileOptions): Bool = {
-    VecInit(s.map(this === _)).asUInt().orR()
-  }
-
-  /** Test if this enumeration is equal to any of the values given as arguments
-    *
-    * @param u1 the first value to look for
-    * @param u2 zero or more additional values to look for
-    * @return a hardware [[Bool]] that indicates if this value matches any of the given values
-    */
-  final def isOneOf(
-    u1: EnumType,
-    u2: EnumType*
-  )(
-    implicit sourceInfo: SourceInfo,
-    compileOptions:      CompileOptions
-  ): Bool = isOneOf(u1 +: u2.toSeq)
-
-  def next(implicit sourceInfo: SourceInfo, compileOptions: CompileOptions): this.type = {
-    if (litOption.isDefined) {
-      val index = factory.all.indexOf(this)
-
-      if (index < factory.all.length - 1) {
-        factory.all(index + 1).asInstanceOf[this.type]
-      } else {
-        factory.all.head.asInstanceOf[this.type]
-      }
-    } else {
-      val enums_with_nexts = factory.all.zip(factory.all.tail :+ factory.all.head)
-      val next_enum = SeqUtils.priorityMux(enums_with_nexts.map { case (e, n) => (this === e, n) })
-      next_enum.asInstanceOf[this.type]
-    }
-  }
-
-  private[chisel3] def bindToLiteral(num: BigInt, w: Width): Unit = {
-    val lit = ULit(num, w)
-    lit.bindLitArg(this)
-  }
-
-  override private[chisel3] def bind(
-    target:          Binding,
-    parentDirection: SpecifiedDirection = SpecifiedDirection.Unspecified
-  ): Unit = {
-    super.bind(target, parentDirection)
-
-    // Make sure we only annotate hardware and not literals
-    if (selfAnnotating && isSynthesizable && topBindingOpt.get.isInstanceOf[ConstrainedBinding]) {
-      annotateEnum()
-    }
-  }
-
-  // This function conducts a depth-wise search to find all enum-type fields within a vector or bundle (or vector of bundles)
-  private def enumFields(d: Aggregate): Seq[Seq[String]] = d match {
-    case v: Vec[_] =>
-      v.sample_element match {
-        case b: Bundle => enumFields(b)
-        case _ => Seq()
-      }
-    case b: Bundle =>
-      b.elements.collect {
-        case (name, e: EnumType) if this.typeEquivalent(e) => Seq(Seq(name))
-        case (name, v: Vec[_]) if this.typeEquivalent(v.sample_element) => Seq(Seq(name))
-        case (name, b2: Bundle) => enumFields(b2).map(name +: _)
-      }.flatten.toSeq
-  }
-
-  private def outerMostVec(d: Data = this): Option[Vec[_]] = {
-    val currentVecOpt = d match {
-      case v: Vec[_] => Some(v)
-      case _ => None
-    }
-
-    d.binding match {
-      case Some(ChildBinding(parent)) =>
-        outerMostVec(parent) match {
-          case outer @ Some(_) => outer
-          case None            => currentVecOpt
-        }
-      case _ => currentVecOpt
-    }
-  }
-
-  private def annotateEnum(): Unit = {
-    val anno = outerMostVec() match {
-      case Some(v) => EnumVecChiselAnnotation(v, enumTypeName, enumFields(v))
-      case None    => EnumComponentChiselAnnotation(this, enumTypeName)
-    }
-
-    if (!Builder.enumAnnos.contains(anno)) {
-      Builder.enumAnnos += anno
-      annotate(anno)
-    }
-
-    if (!Builder.enumAnnos.contains(factory.globalAnnotation)) {
-      Builder.enumAnnos += factory.globalAnnotation
-      annotate(factory.globalAnnotation)
-    }
-  }
-
-  protected def enumTypeName: String = factory.enumTypeName
-
-  def toPrintable: Printable = {
-    implicit val sourceInfo = UnlocatableSourceInfo
-    implicit val compileOptions = ExplicitCompileOptions.Strict
-    val allNames = factory.allNames.zip(factory.all)
-    val nameSize = allNames.map(_._1.length).max
-    def leftPad(str: String): String = {
-      str.reverse.padTo(nameSize, ' ').reverse
-    }
-    val allNamesPadded = allNames.map { case (name, value) => leftPad(name) -> value }
-
-    val result = Wire(Vec(nameSize, UInt(8.W))).suggestName(s"_${enumTypeName}Printable")
-    result.foreach(_ := '?'.U)
-
-    for ((name, value) <- allNamesPadded) {
-      when(this === value) {
-        for ((r, c) <- result.zip(name)) {
-          r := c.toChar.U
-        }
-      }
-    }
-    result.map(Character(_)).foldLeft(p"")(_ + _)
-  }
-}
-
-abstract class EnumFactory {
-  class Type extends EnumType(this)
-  object Type {
-    def apply(): Type = EnumFactory.this.apply()
-  }
-
-  private var id:             BigInt = 0
-  private[chisel3] var width: Width = 0.W
-
-  private case class EnumRecord(inst: Type, name: String)
-  private val enumRecords = mutable.ArrayBuffer.empty[EnumRecord]
-
-  private def enumNames = enumRecords.map(_.name).toSeq
-  private def enumValues = enumRecords.map(_.inst.litValue).toSeq
-  private def enumInstances = enumRecords.map(_.inst).toSeq
-
-  private[chisel3] val enumTypeName = getClass.getName.init
-
-  // Do all bitvectors of this Enum's width represent legal states?
-  private[chisel3] def isTotal: Boolean = {
-    (this.getWidth < 31) && // guard against Integer overflow
-    (enumRecords.size == (1 << this.getWidth))
-  }
-
-  private[chisel3] def globalAnnotation: EnumDefChiselAnnotation =
-    EnumDefChiselAnnotation(enumTypeName, (enumNames, enumValues).zipped.toMap)
-
-  def getWidth: Int = width.get
-
-  def all: Seq[Type] = enumInstances
-  /* Accessor for Seq of names in enumRecords */
-  def allNames: Seq[String] = enumNames
-
-  private[chisel3] def nameOfValue(id: BigInt): Option[String] = {
-    enumRecords.find(_.inst.litValue == id).map(_.name)
-  }
-
-  protected def Value: Type = macro EnumMacros.ValImpl
-  protected def Value(id: UInt): Type = macro EnumMacros.ValCustomImpl
-
-  protected def do_Value(name: String): Type = {
-    val result = new Type
-
-    // We have to use UnknownWidth here, because we don't actually know what the final width will be
-    result.bindToLiteral(id, UnknownWidth())
-
-    enumRecords.append(EnumRecord(result, name))
-
-    width = (1.max(id.bitLength)).W
-    id += 1
-
-    result
-  }
-
-  protected def do_Value(name: String, id: UInt): Type = {
-    // TODO: These throw ExceptionInInitializerError which can be confusing to the user. Get rid of the error, and just
-    // throw an exception
-    if (id.litOption.isEmpty) {
-      throwException(s"$enumTypeName defined with a non-literal type")
-    }
-    if (id.litValue < this.id) {
-      throwException(s"Enums must be strictly increasing: $enumTypeName")
-    }
-
-    this.id = id.litValue
-    do_Value(name)
-  }
-
-  def apply(): Type = new Type
-
-  private def castImpl(
-    n:    UInt,
-    warn: Boolean
-  )(
-    implicit sourceInfo:      SourceInfo,
-    connectionCompileOptions: CompileOptions
-  ): Type = {
-    if (n.litOption.isDefined) {
-      enumInstances.find(_.litValue == n.litValue) match {
-        case Some(result) => result
-        case None         => throwException(s"${n.litValue} is not a valid value for $enumTypeName")
-      }
-    } else if (!n.isWidthKnown) {
-      throwException(s"Non-literal UInts being cast to $enumTypeName must have a defined width")
-    } else if (n.getWidth > this.getWidth) {
-      throwException(s"The UInt being cast to $enumTypeName is wider than $enumTypeName's width ($getWidth)")
-    } else {
-      if (!Builder.suppressEnumCastWarning && warn && !this.isTotal) {
-        Builder.warning(
-          s"Casting non-literal UInt to $enumTypeName. You can use $enumTypeName.safe to cast without this warning."
-        )
-      }
-      val glue = Wire(new UnsafeEnum(width))
-      glue := n
-      val result = Wire(new Type)
-      result := glue
-      result
-    }
-  }
-
-  /** Cast an [[UInt]] to the type of this Enum
-    *
-    * @note will give a Chisel elaboration time warning if the argument could hit invalid states
-    * @param n the UInt to cast
-    * @return the equivalent Enum to the value of the cast UInt
-    */
-  def apply(n: UInt)(implicit sourceInfo: SourceInfo, connectionCompileOptions: CompileOptions): Type =
-    castImpl(n, warn = true)
-
-  /** Safely cast an [[UInt]] to the type of this Enum
-    *
-    * @param n the UInt to cast
-    * @return the equivalent Enum to the value of the cast UInt and a Bool indicating if the
-    *         Enum is valid
-    */
-  def safe(n: UInt)(implicit sourceInfo: SourceInfo, connectionCompileOptions: CompileOptions): (Type, Bool) = {
-    val t = castImpl(n, warn = false)
-    (t, t.isValid)
-  }
-}
-
-private[chisel3] object EnumMacros {
-  def ValImpl(c: Context): c.Tree = {
-    import c.universe._
-
-    // Much thanks to michael_s for this solution:
-    // stackoverflow.com/questions/18450203/retrieve-the-name-of-the-value-a-scala-macro-invocation-will-be-assigned-to
-    val term = c.internal.enclosingOwner
-    val name = term.name.decodedName.toString.trim
-
-    if (name.contains(" ")) {
-      c.abort(c.enclosingPosition, "Value cannot be called without assigning to an enum")
-    }
-
-    q"""this.do_Value($name)"""
-  }
-
-  def ValCustomImpl(c: Context)(id: c.Expr[UInt]): c.universe.Tree = {
-    import c.universe._
-
-    val term = c.internal.enclosingOwner
-    val name = term.name.decodedName.toString.trim
-
-    if (name.contains(" ")) {
-      c.abort(c.enclosingPosition, "Value cannot be called without assigning to an enum")
-    }
-
-    q"""this.do_Value($name, $id)"""
-  }
-}
-
-// This is an enum type that can be connected directly to UInts. It is used as a "glue" to cast non-literal UInts
-// to enums.
-private[chisel3] class UnsafeEnum(override val width: Width) extends EnumType(UnsafeEnum, selfAnnotating = false) {
-  override def cloneType: this.type = new UnsafeEnum(width).asInstanceOf[this.type]
-}
-private object UnsafeEnum extends EnumFactory
-
-/** Suppress enum cast warnings
-  *
-  * Users should use [[EnumFactory.safe <EnumType>.safe]] when possible.
-  *
-  * This is primarily used for casting from [[UInt]] to a Bundle type that contains an Enum.
-  * {{{
-  * class MyBundle extends Bundle {
-  *   val addr = UInt(8.W)
-  *   val op = OpEnum()
-  * }
-  *
-  * // Since this is a cast to a Bundle, cannot use OpCode.safe
-  * val bundle = suppressEnumCastWarning {
-  *   someUInt.asTypeOf(new MyBundle)
-  * }
-  * }}}
-  */
-object suppressEnumCastWarning {
-  def apply[T](block: => T): T = {
-    val parentWarn = Builder.suppressEnumCastWarning
-
-    Builder.suppressEnumCastWarning = true
-
-    val res = block // execute block
-
-    Builder.suppressEnumCastWarning = parentWarn
-    res
-  }
-}