Fix and test for #2530.

1 files changed, 86 insertions, 0 deletions

diff --git a/test/files/jvm/t2530.scala b/test/files/jvm/t2530.scala
new file mode 100644
index 0000000000..642fb05a5d
--- /dev/null
+++ b/test/files/jvm/t2530.scala
@@ -0,0 +1,86 @@
+import scala.actors.{Future, Futures}
+
+object Test {
+
+  def main(args:Array[String]) : Unit = {
+    //scala.actors.Debug.level = 3
+    val size = /*if (args.length > 0) Integer.parseInt(args(0)) else*/ 8
+    val (m,n) = (size, size)
+    def random = (for (i <- 0 until m*n) yield java.lang.Math.random).toArray
+    val A = Matrix(m, n, random)
+    val B = Matrix(m, n, random)
+    val format = new java.text.DecimalFormat("000.00'ms'");
+    var iter = 1
+    val done = 21
+    while (iter < done) {
+      val start = System.nanoTime()
+      val result = A * B
+      val time = System.nanoTime() - start
+      result match {
+        case Some(result) => {
+          printf("     Iteration %2d succeeded %n", iter/*, format.format(time / 1e6)*/)
+          iter += 1
+        }
+        case None => {
+          printf(">>>> Iteration %2d failed after %s <<<<< %n", iter, format.format(time / 1e6))
+          iter = done
+        }
+      }
+    }
+    println("Test done with no deadlock. Try again, it will not occur...")
+  }
+}
+
+case class Matrix(numRows: Int, numCols: Int, values: Array[Double])  {
+
+  def this(m:Int, n:Int) = this(m, n, new Array[Double](m*n))
+
+  def offset(i:Int, j:Int) = i * numCols + j
+  def apply(i:Int, j:Int) = values( offset(i,j) )
+  def update(i:Int, j:Int, value:Double) = values(offset(i, j)) = value;
+
+  def *(by:Matrix) = {
+    val aM = numRows
+    val aN = numCols
+    assert(aM == by.numCols)
+    assert(aN == by.numRows)
+    val resultMatrix = new Matrix(aM, aM)
+    val m = aM.asInstanceOf[Int]
+    val n = aN.asInstanceOf[Int]
+
+    val rows = for (j <- 0 until m) yield {
+      Futures.future {
+        val b_j = new Array[Double](n)
+        var k = 0
+        while (k < n) { // sadly, while loops are still faster than for loops
+          b_j(k) = by(k,j)
+          k += 1
+        }
+        var i = 0
+        while (i < m) {
+          var s = 0.0d;
+          k = 0
+          while (k < n) {
+            s += Matrix.this(i,k) * b_j(k)
+            k += 1
+          }
+          resultMatrix(i,j) = s
+          i += 1
+        }
+        //printf("future %d of %d completed.%n", j, m)
+        j
+      }
+    }
+
+    // rows.foreach { x=> x() } // This appears to force sequential execution, so use:
+    // timeout is 10 years; see http://lampsvn.epfl.ch/trac/scala/ticket/2515
+
+    val done = Futures.awaitAll(10*365*24*60*60*1000, rows.toArray : _*) // list to array, as varargs.
+
+    if (done.contains(None))
+      None
+    else
+      Some(resultMatrix)
+  }
+
+}