Hooked in the DeVirtualize phase again, though ...

Hooked in the DeVirtualize phase again, though it only runs with
-Xexperimental, and even then it does not work yet.

3 files changed, 30 insertions, 20 deletions

diff --git a/src/compiler/scala/tools/nsc/Global.scala b/src/compiler/scala/tools/nsc/Global.scala
index 4d00907934..75a57a3ff4 100644
--- a/src/compiler/scala/tools/nsc/Global.scala
+++ b/src/compiler/scala/tools/nsc/Global.scala
@@ -291,6 +291,10 @@ class Global(var settings: Settings, var reporter: Reporter) extends SymbolTable
     val global: Global.this.type = Global.this
   }
 
+  object devirtualize extends DeVirtualize {
+    val global: Global.this.type = Global.this
+  }
+
   object liftcode extends LiftCode {
     val global: Global.this.type = Global.this
   }
@@ -396,7 +400,11 @@ class Global(var settings: Settings, var reporter: Reporter) extends SymbolTable
     analyzer.namerFactory: SubComponent, // note: types are there because otherwise
     analyzer.typerFactory: SubComponent, // consistency check after refchecks would fail.
     superAccessors,  // add super accessors
-    pickler,         // serialize symbol tables
+    pickler         // serialize symbol tables
+  ) ::: (
+    // Desugar virtual classes
+    if (settings.Xexperimental.value) List(devirtualize) else List()
+  ) ::: List(
     refchecks        // perform reference and override checking, translate nested objects
   ) ::: (
     if (forJVM) List(liftcode) else List() // generate reified trees
diff --git a/src/compiler/scala/tools/nsc/ast/parser/Parsers.scala b/src/compiler/scala/tools/nsc/ast/parser/Parsers.scala
index 340f403f9f..c2e1bd1e7e 100644
--- a/src/compiler/scala/tools/nsc/ast/parser/Parsers.scala
+++ b/src/compiler/scala/tools/nsc/ast/parser/Parsers.scala
@@ -2163,7 +2163,9 @@ trait Parsers extends NewScanners with MarkupParsers {
           else (accessModifierOpt(), paramClauses(name, implicitClassViews, mods.hasFlag(Flags.CASE)))
         val thistpe = requiresTypeOpt()
         var mods1 = mods
-        if (inToken == SUBTYPE) mods1 = mods | Flags.DEFERRED
+        if (settings.Xexperimental.value) {
+          if (inToken == SUBTYPE) mods1 = mods | Flags.DEFERRED
+	}
         var template = templateOpt(mods1, name, constrMods withAnnotations constrAnnots, vparamss)
         if (!thistpe.isEmpty) {
           if (template.self.isEmpty) {
diff --git a/src/compiler/scala/tools/nsc/typechecker/DeVirtualize.scala b/src/compiler/scala/tools/nsc/typechecker/DeVirtualize.scala
index b46464646f..e88ba6f194 100644
--- a/src/compiler/scala/tools/nsc/typechecker/DeVirtualize.scala
+++ b/src/compiler/scala/tools/nsc/typechecker/DeVirtualize.scala
@@ -69,10 +69,10 @@ abstract class DeVirtualize extends InfoTransform with TypingTransformers {
    */
   object devirtualizeMap extends TypeMap {
     def apply(tp: Type): Type = {
-      println("devirtualizeMap on " + tp)
+//      println("devirtualizeMap on " + tp)
       mapOver(tp) match {
       case tp1 @ ClassInfoType(parents, decls, clazz) if containsVirtuals(clazz) =>
-        println(clazz + " contains virtuals")
+//        println(clazz + " contains virtuals")
         transformOwnerInfo(clazz) // we might need to do this in two phases: enter/resolve
         val ds = decls.toList
         val decls1 = newScope(ds)
@@ -80,7 +80,7 @@ abstract class DeVirtualize extends InfoTransform with TypingTransformers {
           if (m.isVirtualClass) devirtualize(m, decls1)
         for (m <- classesInNeedOfFactories(clazz))
           addFactory(m, clazz, decls1)
-        println("Built ourselves a " + ClassInfoType(parents, decls1, clazz))
+//        println("Built ourselves a " + ClassInfoType(parents, decls1, clazz))
         ClassInfoType(parents, decls1, clazz)
       case tp1 @ ThisType(clazz) if clazz.isVirtualClass =>
         ThisType(workerTrait(clazz))
@@ -126,10 +126,10 @@ abstract class DeVirtualize extends InfoTransform with TypingTransformers {
 
   /** The abstract type corresponding to a virtual class. */
   protected def abstractType(clazz: Symbol): Symbol = atPhase(ownPhase.next) {
-    println("Looking up the abstract type for " + clazz)
+//    println("Looking up the abstract type for " + clazz)
     val tsym = clazz.owner.info.member(clazz.name)
     assert(tsym.isAbstractType, clazz)
-    println("Found " + tsym)
+//    println("Found " + tsym)
     tsym
   }
 
@@ -249,7 +249,7 @@ abstract class DeVirtualize extends InfoTransform with TypingTransformers {
    *  @param  scope    The scope into which factory is entered
    */
   def addFactory(clazz: Symbol, owner: Symbol, scope: Scope) {
-    println("Adding a factory to " + clazz.owner + "." + clazz)
+//    println("Adding a factory to " + clazz.owner + "." + clazz)
     val pos = if (clazz.owner == owner) clazz.pos else owner.pos
     val factory = owner.newMethod(pos, factoryName(clazz.name))
       .setFlag(clazz.flags & factoryFlagMask)
@@ -310,7 +310,7 @@ abstract class DeVirtualize extends InfoTransform with TypingTransformers {
      *  to template body `stats'
      */
     override def transformStats(stats: List[Tree], exprOwner: Symbol): List[Tree] = {
-      println("QUX!")
+//      println("QUX!")
       val stats1 = stats flatMap transformStat map transform
       val newDefs = new ListBuffer[Tree]
       if (currentOwner.isClass && containsVirtuals(currentOwner)) {
@@ -373,28 +373,28 @@ abstract class DeVirtualize extends InfoTransform with TypingTransformers {
      *  abstract type and worker traits.
      */
     protected def transformStat(tree: Tree): List[Tree] = {
-      println("QUZZ!")
+//      println("QUZZ!")
       tree match {
       case ClassDef(mods, name, tparams, templ @ Template(parents, self, body)) if (tree.symbol.isVirtualClass) =>
-      println("QUXX!")
+//      println("QUXX!")
         val clazz = tree.symbol
-      println("QUXY!")
+//      println("QUXY!")
         val absTypeSym = abstractType(clazz)
-      println("QUXY2!")
+//      println("QUXY2!")
         val workerTraitSym = workerTrait(clazz)
-      println("QUXY3!")
+//      println("QUXY3!")
         val abstypeDef = TypeDef(abstractType(clazz))
-      println("QUXY4!")
+//      println("QUXY4!")
         val workerTraitDef = ClassDef(
           workerTraitSym,
           Modifiers(0),
           List(List()),
           List(List()),
           body)
-      println("QUXY5!")
+//      println("QUXY5!")
         new ChangeOwnerTraverser(clazz, workerTraitSym)(
           new ChangeOwnerTraverser(templ.symbol, workerTraitDef.impl.symbol)(workerTraitDef.impl))
-      println("QUXY6!")
+//      println("QUXY6!")
         List(abstypeDef, workerTraitDef) map localTyper.typed
       case _ =>
         List(tree)
@@ -402,12 +402,12 @@ abstract class DeVirtualize extends InfoTransform with TypingTransformers {
     }
 
     override def transform(tree: Tree): Tree = {
-      println("FOOB!")
+//      println("FOOB!")
       tree match {
         // Replace references to VC.this and VC.super where VC is a virtual class
         // with VC$trait.this and VC$trait.super
         case This(_) | Super(_, _) if tree.symbol.isVirtualClass =>
-      println("BARB!")
+//      println("BARB!")
           tree setSymbol workerTrait(tree.symbol)
 
         // Replace a new VC().init() where VC is a virtual class with new$VC
@@ -424,7 +424,7 @@ abstract class DeVirtualize extends InfoTransform with TypingTransformers {
           }
 
         case _ =>
-      println("BAZ!")
+//      println("BAZ!")
           super.transform(tree)
       }
     } setType devirtualizeMap(tree.tpe)