diff --git a/test_conformance/subgroups/subgroup_common_templates.h b/test_conformance/subgroups/subgroup_common_templates.h
index 641c1875..0ffa46c8 100644
--- a/test_conformance/subgroups/subgroup_common_templates.h
+++ b/test_conformance/subgroups/subgroup_common_templates.h
@@ -481,12 +481,12 @@ template <typename Ty, ShuffleOp operation> struct SHF
 
     static void gen(Ty *x, Ty *t, cl_int *m, const WorkGroupParams &test_params)
     {
-        int i, ii, j, k, l, n, delta;
+        int i, ii, j, k, n, delta;
+        cl_uint l;
         int nw = test_params.local_workgroup_size;
         int ns = test_params.subgroup_size;
         int ng = test_params.global_workgroup_size;
         int nj = (nw + ns - 1) / ns;
-        int d = ns > 100 ? 100 : ns;
         ii = 0;
         ng = ng / nw;
         for (k = 0; k < ng; ++k)
@@ -498,33 +498,10 @@ template <typename Ty, ShuffleOp operation> struct SHF
                 for (i = 0; i < n; ++i)
                 {
                     int midx = 4 * ii + 4 * i + 2;
-                    l = (int)(genrand_int32(gMTdata) & 0x7fffffff)
-                        % (d > n ? n : d);
-                    switch (operation)
-                    {
-                        case ShuffleOp::shuffle:
-                        case ShuffleOp::shuffle_xor:
-                            // storing information about shuffle index
-                            m[midx] = (cl_int)l;
-                            break;
-                        case ShuffleOp::shuffle_up:
-                            delta = l; // calculate delta for shuffle up
-                            if (i - delta < 0)
-                            {
-                                delta = i;
-                            }
-                            m[midx] = (cl_int)delta;
-                            break;
-                        case ShuffleOp::shuffle_down:
-                            delta = l; // calculate delta for shuffle down
-                            if (i + delta >= n)
-                            {
-                                delta = n - 1 - i;
-                            }
-                            m[midx] = (cl_int)delta;
-                            break;
-                        default: break;
-                    }
+                    l = (((cl_uint)(genrand_int32(gMTdata) & 0x7fffffff) + 1)
+                         % (ns * 2 + 1))
+                        - 1;
+                    m[midx] = l;
                     cl_ulong number = genrand_int64(gMTdata);
                     set_value(t[ii + i], number);
                 }
@@ -542,7 +519,8 @@ template <typename Ty, ShuffleOp operation> struct SHF
     static test_status chk(Ty *x, Ty *y, Ty *mx, Ty *my, cl_int *m,
                            const WorkGroupParams &test_params)
     {
-        int ii, i, j, k, l, n;
+        int ii, i, j, k, n;
+        cl_uint l;
         int nw = test_params.local_workgroup_size;
         int ns = test_params.subgroup_size;
         int ng = test_params.global_workgroup_size;
@@ -567,32 +545,42 @@ template <typename Ty, ShuffleOp operation> struct SHF
                 { // inside the subgroup
                   // shuffle index storage
                     int midx = 4 * ii + 4 * i + 2;
-                    l = (int)m[midx];
+                    l = m[midx];
                     rr = my[ii + i];
+                    cl_uint tr_idx;
+                    bool skip = false;
                     switch (operation)
                     {
                         // shuffle basic - treat l as index
-                        case ShuffleOp::shuffle: tr = mx[ii + l]; break;
-                        // shuffle up - treat l as delta
-                        case ShuffleOp::shuffle_up: tr = mx[ii + i - l]; break;
-                        // shuffle up - treat l as delta
-                        case ShuffleOp::shuffle_down:
-                            tr = mx[ii + i + l];
-                            break;
+                        case ShuffleOp::shuffle: tr_idx = l; break;
                         // shuffle xor - treat l as mask
-                        case ShuffleOp::shuffle_xor:
-                            tr = mx[ii + (i ^ l)];
+                        case ShuffleOp::shuffle_xor: tr_idx = i ^ l; break;
+                        // shuffle up - treat l as delta
+                        case ShuffleOp::shuffle_up:
+                            if (l >= ns) skip = true;
+                            tr_idx = i - l;
+                            break;
+                        // shuffle down - treat l as delta
+                        case ShuffleOp::shuffle_down:
+                            if (l >= ns) skip = true;
+                            tr_idx = i + l;
                             break;
                         default: break;
                     }
 
-                    if (!compare(rr, tr))
+                    if (!skip && tr_idx < n)
                     {
-                        log_error("ERROR: sub_group_%s(%s) mismatch for "
-                                  "local id %d in sub group %d in group %d\n",
-                                  operation_names(operation),
-                                  TypeManager<Ty>::name(), i, j, k);
-                        return TEST_FAIL;
+                        tr = mx[ii + tr_idx];
+
+                        if (!compare(rr, tr))
+                        {
+                            log_error("ERROR: sub_group_%s(%s) mismatch for "
+                                      "local id %d in sub group %d in group "
+                                      "%d\n",
+                                      operation_names(operation),
+                                      TypeManager<Ty>::name(), i, j, k);
+                            return TEST_FAIL;
+                        }
                     }
                 }
             }