API Cleanup - Width

Add simple documentation
trait Width -> abstract class Width
case class UnknownWidth -> case object UnknownWidth

8 files changed, 21 insertions, 20 deletions

diff --git a/src/main/scala/firrtl/Emitter.scala b/src/main/scala/firrtl/Emitter.scala
index 1455b912..7af2017c 100644
--- a/src/main/scala/firrtl/Emitter.scala
+++ b/src/main/scala/firrtl/Emitter.scala
@@ -56,7 +56,7 @@ object FIRRTLEmitter extends Emitter {
 
 case class VIndent()
 case object VRandom extends Expression {
-  def tpe = UIntType(UnknownWidth())
+  def tpe = UIntType(UnknownWidth)
 }
 class VerilogEmitter extends Emitter {
    val tab = "  "
diff --git a/src/main/scala/firrtl/IR.scala b/src/main/scala/firrtl/IR.scala
index 0f4630b8..e11c2334 100644
--- a/src/main/scala/firrtl/IR.scala
+++ b/src/main/scala/firrtl/IR.scala
@@ -126,26 +126,27 @@ case class Stop(info: Info, ret: Int, clk: Expression, en: Expression) extends S
 case class Print(info: Info, string: StringLit, args: Seq[Expression], clk: Expression, en: Expression) extends Stmt with HasInfo
 case class Empty() extends Stmt
 
-trait Width extends AST {
+abstract class Width extends AST {
   def +(x: Width): Width = (this, x) match {
     case (a: IntWidth, b: IntWidth) => IntWidth(a.width + b.width)
-    case _ => UnknownWidth()
+    case _ => UnknownWidth
   }
   def -(x: Width): Width = (this, x) match {
     case (a: IntWidth, b: IntWidth) => IntWidth(a.width - b.width)
-    case _ => UnknownWidth()
+    case _ => UnknownWidth
   }
   def max(x: Width): Width = (this, x) match {
     case (a: IntWidth, b: IntWidth) => IntWidth(a.width max b.width)
-    case _ => UnknownWidth()
+    case _ => UnknownWidth
   }
   def min(x: Width): Width = (this, x) match {
     case (a: IntWidth, b: IntWidth) => IntWidth(a.width min b.width)
-    case _ => UnknownWidth()
+    case _ => UnknownWidth
   }
 }
-case class IntWidth(width: BigInt) extends Width 
-case class UnknownWidth() extends Width
+/** Positive Integer Bit Width of a [[GroundType]] */
+case class IntWidth(width: BigInt) extends Width
+case object UnknownWidth extends Width
 
 /** Orientation of [[Field]] */
 abstract class Orientation extends AST
diff --git a/src/main/scala/firrtl/Serialize.scala b/src/main/scala/firrtl/Serialize.scala
index c8ea9e0f..e81ecba9 100644
--- a/src/main/scala/firrtl/Serialize.scala
+++ b/src/main/scala/firrtl/Serialize.scala
@@ -163,7 +163,7 @@ class Serialize {
 
   def serialize(w: Width): String = {
     w match {
-      case w:UnknownWidth => ""
+      case UnknownWidth => ""
       case w: IntWidth => s"<${w.width.toString}>"
       case w: VarWidth => s"<${w.name}>"
     }
diff --git a/src/main/scala/firrtl/Utils.scala b/src/main/scala/firrtl/Utils.scala
index 9d8b9360..408359f0 100644
--- a/src/main/scala/firrtl/Utils.scala
+++ b/src/main/scala/firrtl/Utils.scala
@@ -204,8 +204,8 @@ object Utils extends LazyLogging {
    def mux_type (t1:Type,t2:Type) : Type = {
       if (wt(t1) == wt(t2)) {
          (t1,t2) match { 
-            case (t1:UIntType,t2:UIntType) => UIntType(UnknownWidth())
-            case (t1:SIntType,t2:SIntType) => SIntType(UnknownWidth())
+            case (t1:UIntType,t2:UIntType) => UIntType(UnknownWidth)
+            case (t1:SIntType,t2:SIntType) => SIntType(UnknownWidth)
             case (t1:VectorType,t2:VectorType) => VectorType(mux_type(t1.tpe,t2.tpe),t1.size)
             case (t1:BundleType,t2:BundleType) => 
                BundleType((t1.fields,t2.fields).zipped.map((f1,f2) => {
@@ -781,8 +781,8 @@ object Utils extends LazyLogging {
 
      def wipeWidth(): Type = 
        t match {
-         case t: UIntType => UIntType(UnknownWidth())
-         case t: SIntType => SIntType(UnknownWidth())
+         case t: UIntType => UIntType(UnknownWidth)
+         case t: SIntType => SIntType(UnknownWidth)
          case _ => t
        }
    }
diff --git a/src/main/scala/firrtl/Visitor.scala b/src/main/scala/firrtl/Visitor.scala
index e17f0213..ff1f9a49 100644
--- a/src/main/scala/firrtl/Visitor.scala
+++ b/src/main/scala/firrtl/Visitor.scala
@@ -128,9 +128,9 @@ class Visitor(infoMode: InfoMode) extends FIRRTLBaseVisitor[AST]
       case term: TerminalNode => 
         term.getText match {
           case "UInt" => if (ctx.getChildCount > 1) UIntType(IntWidth(string2BigInt(ctx.IntLit.getText))) 
-                         else UIntType( UnknownWidth() )
+                         else UIntType( UnknownWidth )
           case "SInt" => if (ctx.getChildCount > 1) SIntType(IntWidth(string2BigInt(ctx.IntLit.getText))) 
-                         else SIntType( UnknownWidth() )
+                         else SIntType( UnknownWidth )
           case "Clock" => ClockType
           case "{" => BundleType(ctx.field.map(visitField))
         }
diff --git a/src/main/scala/firrtl/WIR.scala b/src/main/scala/firrtl/WIR.scala
index d38efc35..dca1cdff 100644
--- a/src/main/scala/firrtl/WIR.scala
+++ b/src/main/scala/firrtl/WIR.scala
@@ -161,7 +161,7 @@ class WrappedWidth (val w:Width) {
          case (w:MinusWidth) => "(" + w.arg1 + " - " + w.arg2 + ")"
          case (w:ExpWidth) => "exp(" + w.arg1 + ")"
          case (w:IntWidth) => w.width.toString
-         case (w:UnknownWidth) => "?"
+         case UnknownWidth => "?"
       }
    }
    def ww (w:Width) : WrappedWidth = new WrappedWidth(w)
@@ -200,7 +200,7 @@ class WrappedWidth (val w:Width) {
                case (w1:MinusWidth,w2:MinusWidth) => 
                   (ww(w1.arg1) == ww(w2.arg1) && ww(w1.arg2) == ww(w2.arg2)) || (ww(w1.arg1) == ww(w2.arg2) && ww(w1.arg2) == ww(w2.arg1))
                case (w1:ExpWidth,w2:ExpWidth) => ww(w1.arg1) == ww(w2.arg1)
-               case (w1:UnknownWidth,w2:UnknownWidth) => true
+               case (UnknownWidth, UnknownWidth) => true
                case (w1,w2) => false
             }
          }
diff --git a/src/main/scala/firrtl/passes/Checks.scala b/src/main/scala/firrtl/passes/Checks.scala
index 0857382b..a88ad051 100644
--- a/src/main/scala/firrtl/passes/Checks.scala
+++ b/src/main/scala/firrtl/passes/Checks.scala
@@ -290,8 +290,8 @@ object CheckTypes extends Pass with LazyLogging {
    class ValidIfPassiveTypes(info:Info) extends PassException(s"${info}: [module ${mname}]  Must validif a passive type.")
    class ValidIfCondUInt(info:Info) extends PassException(s"${info}: [module ${mname}]  A validif condition must be of type UInt.")
    //;---------------- Helper Functions --------------
-   def ut () : UIntType = UIntType(UnknownWidth())
-   def st () : SIntType = SIntType(UnknownWidth())
+   def ut () : UIntType = UIntType(UnknownWidth)
+   def st () : SIntType = SIntType(UnknownWidth)
    
    def check_types_primop (e:DoPrim, errors:Errors, info:Info) : Unit = {
       def all_same_type (ls:Seq[Expression]) : Unit = {
diff --git a/src/main/scala/firrtl/passes/Passes.scala b/src/main/scala/firrtl/passes/Passes.scala
index 0243c6cd..42b51268 100644
--- a/src/main/scala/firrtl/passes/Passes.scala
+++ b/src/main/scala/firrtl/passes/Passes.scala
@@ -159,7 +159,7 @@ object InferTypes extends Pass {
    }
    def remove_unknowns_w (w:Width)(implicit namespace: Namespace):Width = {
       w match {
-         case w:UnknownWidth => VarWidth(namespace.newName("w"))
+         case UnknownWidth => VarWidth(namespace.newName("w"))
          case w => w
       }
    }