--- jsr166/src/test/loops/ScalarLongSort.java	2010/09/01 07:47:27	1.3
+++ jsr166/src/test/loops/ScalarLongSort.java	2010/09/19 12:55:37	1.4
@@ -4,22 +4,37 @@
  * http://creativecommons.org/licenses/publicdomain
  */
 
-import java.util.*;
 import java.util.concurrent.*;
-
-// Based very loosely on cilksort
+import java.util.*;
 
 class ScalarLongSort {
-    static final long NPS = (1000L * 1000 * 1000); // time conversion
+    static final long NPS = (1000L * 1000 * 1000);
 
     static int THRESHOLD;
     static final boolean warmup = true;
 
-    public static void main(String[] args) throws Exception {
+    public static void main (String[] args) throws Exception {
+        int procs = 0;
         int n = 1 << 22;
-        int sreps = 2;
         int reps = 20;
+        int sreps = 2;
+        try {
+            if (args.length > 0)
+                procs = Integer.parseInt(args[0]);
+            if (args.length > 1)
+                n = Integer.parseInt(args[1]);
+            if (args.length > 2)
+                reps = Integer.parseInt(args[1]);
+        }
+        catch (Exception e) {
+            System.out.println("Usage: java ScalarLongSort threads n reps");
+            return;
+        }
+        ForkJoinPool pool = procs == 0? new ForkJoinPool() : 
+            new ForkJoinPool(procs);
+
         long[] a = new long[n];
+        seqRandomFill(a, 0, n);
 
         if (warmup) {
             System.out.printf("Sorting %d longs, %d replications\n", n, 1);
@@ -31,7 +46,6 @@ class ScalarLongSort {
             checkSorted(a);
         }
 
-        ForkJoinPool pool = new ForkJoinPool();
         // for now hardwire 8 * #CPUs leaf tasks
         THRESHOLD = 1 + ((n + 7) >>> 3) / pool.getParallelism();
         //        THRESHOLD = 1 + ((n + 15) >>> 4) / pool.getParallelism();
@@ -66,9 +80,9 @@ class ScalarLongSort {
     }
 
     static final class Sorter extends RecursiveAction {
-        final long[] a;
+        final long[] a; 
         final long[] w;
-        final int origin;
+        final int origin; 
         final int n;
         Sorter(long[] a, long[] w, int origin, int n) {
             this.a = a; this.w = w; this.origin = origin; this.n = n;
@@ -79,24 +93,25 @@ class ScalarLongSort {
             if (n <= THRESHOLD)
                 Arrays.sort(a, l, l+n);
             else { // divide in quarters to ensure sorted array in a not w
-                SubSorter rs;
                 int h = n >>> 1;
                 int q = n >>> 2;
                 int u = h + q;
-                (rs = new SubSorter
-                 (new Sorter(a, w, l+h, q),
-                  new Sorter(a, w, l+u, n-u),
-                  new Merger(a, w, l+h, q, l+u, n-u, l+h, null))).fork();
-                (new SubSorter
-                 (new Sorter(a, w, l,   q),
-                  new Sorter(a, w, l+q, h-q),
-                  new Merger(a, w, l,   q, l+q, h-q, l, null))).compute();
+                SubSorter rs = new SubSorter
+                    (new Sorter(a, w, l+h, q),
+                     new Sorter(a, w, l+u, n-u),
+                     new Merger(a, w, l+h, q, l+u, n-u, l+h, null));
+                rs.fork();
+                Sorter rl = new Sorter(a, w, l+q, h-q);
+                rl.fork();
+                (new Sorter(a, w, l,   q)).compute();
+                rl.join();
+                (new Merger(a, w, l,   q, l+q, h-q, l, null)).compute();
                 rs.join();
                 new Merger(w, a, l, h, l+h, n-h, l, null).compute();
             }
         }
     }
-
+    
     static final class SubSorter extends RecursiveAction {
         final Sorter left;
         final Sorter right;
@@ -115,7 +130,7 @@ class ScalarLongSort {
     static final class Merger extends RecursiveAction {
         final long[] a; final long[] w;
         final int lo; final int ln; final int ro; final int rn; final int wo;
-        final Merger next;
+        Merger next;
         Merger(long[] a, long[] w, int lo, int ln, int ro, int rn, int wo,
                Merger next) {
             this.a = a;    this.w = w;
@@ -130,9 +145,9 @@ class ScalarLongSort {
          * and finding index of right closest to split point.
          * Uses left-spine decomposition to generate all
          * merge tasks before bottomming out at base case.
-         *
+         * 
          */
-        public void compute() {
+        public final void compute() {
             Merger rights = null;
             int nleft = ln;
             int nright = rn;
@@ -154,8 +169,14 @@ class ScalarLongSort {
                 nleft = lh;
                 nright = rh;
             }
+            
+            merge(nleft, nright);
+            if (rights != null) 
+                collectRights(rights);
+            
+        }
 
-            // Base case -- merge left and right
+        final void merge(int nleft, int nright) {
             int l = lo;
             int lFence = lo + nleft;
             int r = ro;
@@ -172,20 +193,24 @@ class ScalarLongSort {
                 w[k++] = a[l++];
             while (r < rFence)
                 w[k++] = a[r++];
+        }
 
-            while (rights != null) {
-                rights.join();
-                rights = rights.next;
+        static void collectRights(Merger rt) {
+            while (rt != null) {
+                Merger next = rt.next;
+                rt.next = null;
+                if (rt.tryUnfork()) rt.compute(); else rt.join();
+                rt = next;
             }
         }
 
     }
 
-    static void checkSorted(long[] a)  {
+    static void checkSorted (long[] a)  {
         int n = a.length;
         for (int i = 0; i < n - 1; i++) {
             if (a[i] > a[i+1]) {
-                throw new Error("Unsorted at " + i + ": " +
+                throw new Error("Unsorted at " + i + ": " + 
                                 a[i] + " / " + a[i+1]);
             }
         }
@@ -204,8 +229,12 @@ class ScalarLongSort {
             this.array = array; this.lo = lo; this.hi = hi;
         }
         public void compute() {
-            if (hi - lo <= THRESHOLD)
-                seqRandomFill(array, lo, hi);
+            if (hi - lo <= THRESHOLD) {
+                long[] a = array;
+                ThreadLocalRandom rng = ThreadLocalRandom.current();
+                for (int i = lo; i < hi; ++i)
+                    a[i] = rng.nextLong();
+            }
             else {
                 int mid = (lo + hi) >>> 1;
                 RandomFiller r = new RandomFiller(array, mid, hi);