Make "deprecated public" binding APIs private (#4177)

* Make "deprecated public" binding APIs private

This is done by adding a new package private object "binding" within
which all bindings live. This required changing imports in lots of files
but it makes it much easier to not accidentally create a public binding
in the future.

* [cleanup] Delete @deprecated and private[chisel3] from Binding.scala

These are no longer needed now that all binding are packaged up in a
package private object.

core/src/main/scala/chisel3/Aggregate.scala

@@ -11,6 +11,7 @@ import scala.language.experimental.macros
 import chisel3.experimental.{BaseModule, BundleLiteralException, HasTypeAlias, OpaqueType, VecLiteralException}
 import chisel3.experimental.{requireIsChiselType, requireIsHardware, SourceInfo, UnlocatableSourceInfo}
 import chisel3.internal._
+import chisel3.internal.binding._
 import chisel3.internal.Builder.pushCommand
 import chisel3.internal.firrtl.ir._
 import chisel3.internal.sourceinfo.{SourceInfoTransform, VecTransform}

core/src/main/scala/chisel3/ChiselEnum.scala

@@ -11,17 +11,8 @@ import chisel3.internal.Builder.pushOp
 import chisel3.internal.firrtl.ir.PrimOp._
 import chisel3.internal.firrtl.ir._
 import chisel3.internal.sourceinfo._
-import chisel3.internal.{
-  containsProbe,
-  throwException,
-  Binding,
-  Builder,
-  BuilderContextCache,
-  ChildBinding,
-  ConstrainedBinding,
-  Warning,
-  WarningID
-}
+import chisel3.internal.{containsProbe, throwException, Builder, BuilderContextCache, Warning, WarningID}
+import chisel3.internal.binding.{Binding, ChildBinding, ConstrainedBinding}
 
 import chisel3.experimental.EnumAnnotations._
 

core/src/main/scala/chisel3/Data.scala

@@ -10,6 +10,7 @@ import chisel3.experimental.{prefix, SourceInfo, UnlocatableSourceInfo}
 import chisel3.experimental.dataview.reifySingleData
 import chisel3.internal.Builder.pushCommand
 import chisel3.internal._
+import chisel3.internal.binding._
 import chisel3.internal.sourceinfo._
 import chisel3.internal.firrtl.ir._
 import chisel3.properties.Property

core/src/main/scala/chisel3/Element.scala

@@ -7,6 +7,7 @@ import chisel3.internal.firrtl.ir._
 import chisel3.experimental.SourceInfo
 import chisel3.experimental.dataview.reify
 import chisel3.internal._
+import chisel3.internal.binding._
 
 /** Element is a leaf data type: it cannot contain other [[Data]] objects. Example uses are for representing primitive
   * data types, like integers and bits.

core/src/main/scala/chisel3/Intrinsic.scala

@@ -5,7 +5,8 @@ package chisel3
 import chisel3._
 import chisel3.experimental.{requireIsChiselType, Param, SourceInfo}
 import chisel3.internal.firrtl.ir._
-import chisel3.internal.{Builder, OpBinding}
+import chisel3.internal.Builder
+import chisel3.internal.binding.OpBinding
 import chisel3.internal.Builder.pushCommand
 
 object Intrinsic {

core/src/main/scala/chisel3/Mem.scala

@@ -7,6 +7,7 @@ import scala.language.experimental.macros
 import firrtl.{ir => fir}
 
 import chisel3.internal._
+import chisel3.internal.binding._
 import chisel3.internal.Builder.pushCommand
 import chisel3.internal.firrtl.ir._
 import chisel3.internal.sourceinfo.{MemTransform, SourceInfoTransform}

core/src/main/scala/chisel3/Module.scala

@@ -7,6 +7,7 @@ import scala.collection.mutable.{ArrayBuffer, HashMap, LinkedHashSet}
 import scala.language.experimental.macros
 
 import chisel3.internal._
+import chisel3.internal.binding._
 import chisel3.internal.Builder._
 import chisel3.internal.firrtl.ir._
 import chisel3.experimental.{requireIsChiselType, BaseModule, SourceInfo, UnlocatableSourceInfo}
@@ -833,7 +834,7 @@ package experimental {
       require(!isFullyClosed, "Cannot create secret ports if module is fully closed")
 
       Module.assignCompatDir(iodef)
-      iodef.bind(internal.SecretPortBinding(this), iodef.specifiedDirection)
+      iodef.bind(SecretPortBinding(this), iodef.specifiedDirection)
       iodef
     }
 

core/src/main/scala/chisel3/RawModule.scala

@@ -6,6 +6,7 @@ import scala.util.Try
 import scala.language.experimental.macros
 import chisel3.experimental.{BaseModule, SourceInfo, UnlocatableSourceInfo}
 import chisel3.internal._
+import chisel3.internal.binding._
 import chisel3.experimental.hierarchy.{InstanceClone, ModuleClone}
 import chisel3.properties.{DynamicObject, Property, StaticObject}
 import chisel3.internal.Builder._

core/src/main/scala/chisel3/Reg.scala

@@ -5,6 +5,7 @@ package chisel3
 import scala.language.experimental.macros
 
 import chisel3.internal._
+import chisel3.internal.binding._
 import chisel3.internal.Builder.pushCommand
 import chisel3.internal.firrtl.ir._
 import chisel3.experimental.{requireIsChiselType, requireIsHardware, SourceInfo}

core/src/main/scala/chisel3/connectable/Alignment.scala

@@ -5,7 +5,7 @@ package chisel3.connectable
 import chisel3.{Aggregate, Data, DontCare, SpecifiedDirection}
 import chisel3.experimental.Analog
 import chisel3.reflect.DataMirror
-import chisel3.internal.{ChildBinding, TopBinding}
+import chisel3.internal.binding.{ChildBinding, TopBinding}
 
 // Represent aligned or flipped relative to an original root.
 // Used for walking types and their alignment, accounting for coercion.

core/src/main/scala/chisel3/experimental/Analog.scala

@@ -3,6 +3,7 @@
 package chisel3.experimental
 
 import chisel3.internal._
+import chisel3.internal.binding._
 import chisel3.{ActualDirection, Bits, Data, Element, PString, Printable, RawModule, SpecifiedDirection, UInt, Width}
 
 import scala.collection.mutable

core/src/main/scala/chisel3/experimental/OpaqueType.scala

@@ -3,7 +3,8 @@
 package chisel3.experimental
 
 import chisel3._
-import chisel3.internal.{Builder, ChildBinding}
+import chisel3.internal.Builder
+import chisel3.internal.binding.ChildBinding
 import chisel3.internal.firrtl.ir.Arg
 
 /** Indicates if this Record represents an "Opaque Type"

core/src/main/scala/chisel3/experimental/dataview/package.scala

@@ -4,6 +4,7 @@ package chisel3.experimental
 
 import chisel3._
 import chisel3.internal._
+import chisel3.internal.binding._
 import chisel3.properties.Property
 
 import scala.annotation.{implicitNotFound, tailrec}

core/src/main/scala/chisel3/experimental/hierarchy/core/Lookupable.scala

@@ -10,7 +10,8 @@ import scala.collection.mutable.HashMap
 import chisel3._
 import chisel3.experimental.dataview.{isView, reify, reifySingleData}
 import chisel3.internal.firrtl.ir.{Arg, ILit, Index, ModuleIO, Slot, ULit}
-import chisel3.internal.{throwException, AggregateViewBinding, Builder, ChildBinding, ViewBinding, ViewParent}
+import chisel3.internal.{throwException, Builder, ViewParent}
+import chisel3.internal.binding.{AggregateViewBinding, ChildBinding, CrossModuleBinding, ViewBinding}
 
 /** Represents lookup typeclass to determine how a value accessed from an original IsInstantiable
   *   should be tweaked to return the Instance's version
@@ -71,7 +72,7 @@ object Lookupable {
           case Clone(m: BaseModule) =>
             val newChild = data.cloneTypeFull
             newChild.setRef(data.getRef, true)
-            newChild.bind(internal.CrossModuleBinding)
+            newChild.bind(CrossModuleBinding)
             newChild.setAllParents(Some(m))
             newChild
           case _ => throw new InternalErrorException("Match error: newParent=$newParent")

core/src/main/scala/chisel3/internal/BiConnect.scala

@@ -6,6 +6,7 @@ import chisel3._
 import chisel3.experimental.dataview.{isView, reify, reifyToAggregate}
 import chisel3.experimental.{attach, Analog, BaseModule, SourceInfo}
 import chisel3.properties.Property
+import chisel3.internal.binding._
 import chisel3.internal.Builder.pushCommand
 import chisel3.internal.firrtl.ir.{Connect, DefInvalid}
 import chisel3.internal.firrtl.Converter