More statistics for created and retained trees

Author: odersky

src/dotty/tools/dotc/ast/Trees.scala

@@ -297,6 +297,18 @@ object Trees {
     def orElse[U >: Untyped <: T](that: => Tree[U]): Tree[U] =
       if (this eq genericEmptyTree) that else this
 
+    /** The number of nodes in this tree */
+    def treeSize: Int = {
+      var s = 1
+      def addSize(elem: Any): Unit = elem match {
+        case t: Tree[_] => s += t.treeSize
+        case ts: List[_] => ts foreach addSize
+        case _ =>
+      }
+      productIterator foreach addSize
+      s
+    }
+
     override def toText(printer: Printer) = printer.toText(this)
 
     override def hashCode(): Int = System.identityHashCode(this)

src/dotty/tools/dotc/core/TypeComparer.scala

@@ -195,7 +195,7 @@ class TypeComparer(initctx: Context) extends DotClass {
       val saved = constraint
       val savedSuccessCount = successCount
       val savedTotalCount = totalCount
-      if (Stats.monitored) Stats.record(s"isSubType ${tp1.show} <:< ${tp2.show}")
+      //if (Stats.monitored) Stats.record(s"isSubType ${tp1.show} <:< ${tp2.show}")
       try {
         recCount += 1
 /* !!! DEBUG

src/dotty/tools/dotc/typer/FrontEnd.scala

@@ -6,6 +6,7 @@ import Phases._
 import Contexts._
 import parsing.Parsers.Parser
 import config.Printers._
+import util.Stats._
 
 class FrontEnd extends Phase {
 
@@ -35,13 +36,17 @@ class FrontEnd extends Phase {
     val unit = ctx.compilationUnit
     unit.tpdTree = ctx.typer.typedExpr(unit.untpdTree)
     typr.println("typed: "+unit.source)
+    record("retainedUntypedTrees", unit.untpdTree.treeSize)
+    record("retainedTypedTrees", unit.tpdTree.treeSize)
   }
 
   override def runOn(units: List[CompilationUnit])(implicit ctx: Context): Unit = {
     val unitContexts = units map (unit => ctx.fresh.withCompilationUnit(unit))
     unitContexts foreach (parse(_))
+    record("parsedTrees", ast.Trees.ntrees)
     unitContexts foreach (enterSyms(_))
     unitContexts foreach (typeCheck(_))
+    record("totalTrees", ast.Trees.ntrees)
   }
 
   override def run(implicit ctx: Context): Unit = {

src/dotty/tools/dotc/typer/Typer.scala

@@ -28,7 +28,7 @@ import util.SourcePosition
 import collection.mutable
 import annotation.tailrec
 import Implicits._
-import util.Stats.track
+import util.Stats.{track, record}
 import config.Printers._
 import language.implicitConversions
 
@@ -959,7 +959,7 @@ class Typer extends Namer with Applications with Implicits {
   }
 
   def typedUnadapted(initTree: untpd.Tree, pt: Type = WildcardType)(implicit ctx: Context): Tree = {
-
+    record("typedUnadapted")
     val xtree = expanded(initTree)
     xtree.removeAttachment(TypedAhead) match {
       case Some(ttree) => ttree