Added `combine` and `split` to immutable.HashMap.

Under test/benchmarks there is a `bench` script to run benchmarks - it can be invoked after running building the library.
Review by rompf.

4 files changed, 59 insertions, 2 deletions

diff --git a/test/benchmarks/src/scala/collection/parallel/Benchmarking.scala b/test/benchmarks/src/scala/collection/parallel/Benchmarking.scala
index 371ebccef4..f6aa63cb1a 100644
--- a/test/benchmarks/src/scala/collection/parallel/Benchmarking.scala
+++ b/test/benchmarks/src/scala/collection/parallel/Benchmarking.scala
@@ -92,6 +92,7 @@ trait BenchmarkRegister {
   register(hashtries.Iterate)
   register(hashtries.Construct)
   register(hashtries.Lookup)
+  register(hashtries.Combine)
 }
 
 
diff --git a/test/benchmarks/src/scala/collection/parallel/benchmarks/hashtries/Combine.scala b/test/benchmarks/src/scala/collection/parallel/benchmarks/hashtries/Combine.scala
new file mode 100644
index 0000000000..8c8d17e745
--- /dev/null
+++ b/test/benchmarks/src/scala/collection/parallel/benchmarks/hashtries/Combine.scala
@@ -0,0 +1,55 @@
+package scala.collection.parallel.benchmarks
+package hashtries
+
+
+
+
+import collection.immutable.{HashMap => HashTrie}
+import collection.mutable.HashMap
+
+
+
+
+
+
+class Combine(val size: Int, val parallelism: Int, val runWhat: String) extends Bench with IntInit {
+  var thattrie = new HashTrie[Int, Int]
+  for (i <- size until 2 * size) thattrie += ((i, i))
+  val thatmap = new HashMap[Int, Int]
+  for (i <- size until 2 * size) thatmap += ((i, i))
+
+  def runpar = throw new UnsupportedOperationException
+  def runseq = runhashtrie
+  def runhashtrie = hashtrie combine thattrie
+  def runappendtrie = hashtrie ++ thattrie
+  def runhashmap = hashmap ++ thatmap
+  def companion = Combine
+  def comparisonMap = Map("hashtrie" -> runhashtrie _, "hashmap" -> runhashmap _, "appendtrie" -> runappendtrie _)
+  override def reset = runWhat match {
+    case "appendtrie" => initHashTrie
+    case _ => super.reset
+  }
+}
+
+
+object Combine extends BenchCompanion {
+  def collectionName = "HashTrie"
+  def benchName = "combine";
+  def apply(sz: Int, p: Int, what: String) = new Combine(sz, p, what)
+  override def defaultSize = 5000
+}
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
diff --git a/test/benchmarks/src/scala/collection/parallel/benchmarks/hashtries/Foreach.scala b/test/benchmarks/src/scala/collection/parallel/benchmarks/hashtries/Foreach.scala
index 6002b5d8b8..f53ea02e36 100644
--- a/test/benchmarks/src/scala/collection/parallel/benchmarks/hashtries/Foreach.scala
+++ b/test/benchmarks/src/scala/collection/parallel/benchmarks/hashtries/Foreach.scala
@@ -14,7 +14,7 @@ import collection.mutable.HashMap
 
 class Foreach(val size: Int, val parallelism: Int, val runWhat: String) extends Bench with IntInit {
   def runpar = throw new UnsupportedOperationException
-  def runseq = throw new UnsupportedOperationException
+  def runseq = runhashtrie
   def runhashmap = hashmap.foreach(n => ())
   def runhashtrie = hashtrie.foreach(n => ())
   def companion = Foreach
diff --git a/test/benchmarks/src/scala/collection/parallel/benchmarks/hashtries/IntInit.scala b/test/benchmarks/src/scala/collection/parallel/benchmarks/hashtries/IntInit.scala
index 3328dcbe0f..dbbe64e290 100644
--- a/test/benchmarks/src/scala/collection/parallel/benchmarks/hashtries/IntInit.scala
+++ b/test/benchmarks/src/scala/collection/parallel/benchmarks/hashtries/IntInit.scala
@@ -17,6 +17,7 @@ trait IntInit extends Bench {
   def reset = runWhat match {
     case "hashmap" => initHashMap
     case "hashtrie" => initHashTrie
+    case "seq" => initHashTrie
   }
   def initHashTrie = {
     hashtrie = new HashTrie
@@ -27,4 +28,4 @@ trait IntInit extends Bench {
     for (i <- 0 until size) hashmap += ((i, i))
   }
 
-}
\ No newline at end of file
+}