diff --git a/examples_cuda/sort/sort1.cu b/examples_cuda/sort/sort1.cu
index 8b2c8fc5..49886fdb 100644
--- a/examples_cuda/sort/sort1.cu
+++ b/examples_cuda/sort/sort1.cu
@@ -239,20 +239,26 @@ static void prefix_sum ( int num,  int h[], int * g)
 }
 
 extern "C" __global__
-void sort_ispc ( int n,  unsigned int code[],  int order[],  int ntasks)
+void sort_ispc ( int n,  unsigned int code[],  int order[],  int ntasks,
+    int _hist[],
+    int64 _pair[],
+    int64 _temp[],
+    int _g[])
 {
-   int num = ntasks < 1 ? 13*4 : ntasks;
+   int num = ntasks;
    int span = n / num;
-   int hsize = 256*programCount*num;
 #if 0
-   int *  hist =  new  int [hsize];
-   int64 *  pair =  new  int64 [n];
-   int64 *  temp =  new  int64 [n];
-#else
+   int hsize = 256*programCount*num;
    int *  hist =  __new< int>(hsize);
    int64 *  pair =  __new< int64>(n);
    int64 *  temp =  __new< int64>(n);
    int *  g =  __new<int>(num+1);
+#define ALLOCATED
+#else
+   int * hist = _hist;
+   int64 * pair = _pair;
+   int64 * temp = _temp;
+   int * g = _g;
 #endif
    int pass, i;
 
@@ -262,7 +268,6 @@ void sort_ispc ( int n,  unsigned int code[],  int order[],  int ntasks)
      pack<<<nbx(num),128>>>(span, n, code, pair);
   sync;
 
-#if 1
   for (pass = 0; pass < 4; pass ++)
   {
     //    launch[num] histogram (span, n, pair, pass, hist);
@@ -287,15 +292,9 @@ void sort_ispc ( int n,  unsigned int code[],  int order[],  int ntasks)
   if(programIndex == 0)
     unpack<<<nbx(num),128>>> (span, n, pair, code, order);
   sync;
-#endif
 
-
-#if 0
-  delete hist;
-  delete pair;
-  delete temp;
-#else
-    __delete(g);
+#if ALLOCATED
+  __delete(g);
   __delete(hist);
   __delete(pair);
   __delete(temp);
diff --git a/examples_cuda/sort/sort1.ispc b/examples_cuda/sort/sort1.ispc
index 0c500ed4..e3acb4f0 100644
--- a/examples_cuda/sort/sort1.ispc
+++ b/examples_cuda/sort/sort1.ispc
@@ -194,51 +194,56 @@ task void bumpup (uniform int h[], uniform int g[])
   }
 }
 
-static void prefix_sum (uniform int num, uniform int h[])
+static void prefix_sum (uniform int num, uniform int h[], uniform int g[])
 {
-  uniform int * uniform g = uniform new uniform int [num+1];
   uniform int i;
 
   launch[num] addup (h, g+1);
   sync;
 
-  for (g[0] = 0, i = 1; i < num; i ++) g[i] += g[i-1];
+  g[0] = 0;
+  for (i = 1; i < num; i ++) 
+      g[i] += g[i-1];
 
   launch[num] bumpup (h, g);
   sync;
 
-  delete g;
 }
 
-export void sort_ispc (uniform int n, uniform unsigned int code[], uniform int order[], uniform int ntasks)
+export void sort_ispc (uniform int n, 
+    uniform unsigned int code[], 
+    uniform int order[], 
+    uniform int ntasks,
+    uniform int _hist[],
+    uniform int64 _pair[],
+    uniform int64 _temp[],
+    uniform int _g[])
 {
-  uniform int num = ntasks < 1 ? 13*4*8 : ntasks;
+  uniform int num = ntasks;
   uniform int span = n / num;
+#if 0
   uniform int hsize = 256*programCount*num;
   uniform int * uniform hist = uniform new uniform int [hsize];
   uniform int64 * uniform pair = uniform new uniform int64 [n];
   uniform int64 * uniform temp = uniform new uniform int64 [n];
-  uniform int pass, i;
-
-#if DEBUG
-  if (n < 100)
-  {
-    print ("input: ");
-    for (i = 0; i < n; i ++) print ("%, ", code[i]);
-    print ("\n");
-  }
+  uniform int * uniform g = uniform new uniform int [num+1];
+#else
+   uniform int * uniform hist = _hist;
+   uniform int64 * uniform pair = _pair;
+   uniform int64 * uniform temp = _temp;
+   uniform int * uniform g = _g;
 #endif
+  uniform int pass, i;
 
   launch[num] pack (span, n, code, pair);
   sync;
-#if 0
 
   for (pass = 0; pass < 4; pass ++)
   {
     launch[num] histogram (span, n, pair, pass, hist);
     sync;
 
-    prefix_sum (num, hist);
+    prefix_sum (num, hist, g);
 
     launch[num] permutation (span, n, pair, pass, hist, temp);
     sync;
@@ -250,26 +255,11 @@ export void sort_ispc (uniform int n, uniform unsigned int code[], uniform int o
   launch[num] unpack (span, n, pair, code, order);
   sync;
 
-#if DEBUG
-  for (i = 0; i < n; i ++)
-  {
-    if (i > 0 && code[i-1] > code[i])
-      print ("ERR at % => % > %; ", i, code[i-1], code[i]);
-  }
-
-  if (n < 100)
-  {
-    print ("output: ");
-    for (i = 0; i < n; i ++) print ("%, ", code[i]);
-    print ("\n");
-    print ("order: ");
-    for (i = 0; i < n; i ++) print ("%, ", order[i]);
-    print ("\n");
-  }
-#endif
-#endif
-
+#if ALLOCATED
+  delete g;
   delete hist;
   delete pair;
   delete temp;
+#endif
 }
+
diff --git a/examples_cuda/sort/sort_cu.cpp b/examples_cuda/sort/sort_cu.cpp
index f749d343..ec295434 100644
--- a/examples_cuda/sort/sort_cu.cpp
+++ b/examples_cuda/sort/sort_cu.cpp
@@ -351,8 +351,13 @@ int main (int argc, char *argv[])
   createContext();
   /*******************/
 
+  int ntask = 13*4*8;
   devicePtr d_code   = deviceMalloc(n*sizeof(int));
   devicePtr d_order  = deviceMalloc(n*sizeof(int));
+  devicePtr d_pair   = deviceMalloc(n*2*sizeof(int));
+  devicePtr d_temp   = deviceMalloc(n*2*sizeof(int));
+  devicePtr d_hist   = deviceMalloc(256*32 * ntask * sizeof(int));
+  devicePtr d_g      = deviceMalloc((ntask + 1) * sizeof(int));
 
   for (i = 0; i < m; i ++)
   {
@@ -368,8 +373,11 @@ int main (int argc, char *argv[])
     tISPC2 += (rtc() - t0); // get_elapsed_mcycles();
 #else
     const char * func_name = "sort_ispc";
-    int ntask = 0;
+#if 0
     void *func_args[] = {&n, &d_code, &d_order, &ntask};
+#else
+    void *func_args[] = {&n, &d_code, &d_order, &ntask, &d_hist, &d_pair, &d_temp, &d_g};
+#endif
     const double dt = CUDALaunch(NULL, func_name, func_args);
     tISPC2 += dt;
 #endif