Statistics reporting: aggregate keys with common prefix

Author: odersky

compiler/src/dotty/tools/dotc/util/Stats.scala

@@ -75,6 +75,17 @@ import collection.mutable
     }
   }
 
+  final val GroupChar = '/'
+
+  /** Aggregate all counts of all keys with a common prefix, followed by `:` */
+  private def aggregate(): Unit = {
+    val groups = hits.keys
+      .filter(_.contains(GroupChar))
+      .groupBy(_.takeWhile(_ != GroupChar))
+    for ((prefix, names) <- groups; name <- names)
+      hits(s"Total $prefix") += hits(name)
+  }
+
   def maybeMonitored[T](op: => T)(implicit ctx: Context): T = {
     if (ctx.settings.YdetailedStats.value) {
       val hb = new HeartBeat()
@@ -83,6 +94,7 @@ import collection.mutable
       try op
       finally {
         hb.continue = false
+        aggregate()
         println()
         println(hits.toList.sortBy(_._2).map{ case (x, y) => s"$x -> $y" } mkString "\n")
         println(s"uniqueInfo (size, accesses, collisions): ${ctx.base.uniquesSizes}")