add tag for gather index

include/ck_tile/core/algorithm/indexing_adaptor.hpp

@@ -57,7 +57,7 @@ struct indexing_adaptor_onshot_cached
         return ck_tile::is_known_at_compile_time<IndexingType>::value;
     }
 };
-
+#define Using_Gather  1
 template <typename IndexingType>
 struct indexing_adaptor
 {
@@ -65,8 +65,10 @@ struct indexing_adaptor
     CK_TILE_HOST_DEVICE constexpr indexing_adaptor() = default;
     CK_TILE_HOST_DEVICE constexpr indexing_adaptor(const IndexingType* idx) : cached_idx_(idx) {}
     const IndexingType* cached_idx_;
+#if Using_Gather
     mutable index_t pre_up_index_  = 0;
     mutable index_t pre_low_index_ = 0;
+#endif
 
     template <typename LowIdx, typename UpIdx>
     CK_TILE_HOST_DEVICE constexpr void calculate_lower_index(LowIdx& idx_low,
@@ -76,7 +78,7 @@ struct indexing_adaptor
                       "wrong! inconsistent # of dimension");
 
         idx_low(number<0>{}) = *(cached_idx_ + idx_up[number<0>{}]);
-
+#if Using_Gather
         pre_up_index_  = idx_up[number<0>{}];
         pre_low_index_ = idx_low(number<0>{});
 #if 0
@@ -84,6 +86,7 @@ struct indexing_adaptor
         {
             printf("\n first index from  %d to  %d  \n", idx_up[number<0>{}], idx_low(number<0>{}));
         }
+#endif
 #endif
     }
 
@@ -97,7 +100,9 @@ struct indexing_adaptor
         static_assert(LowIdxDiff::size() == 1 && UpIdxDiff::size() == 1 && LowIdx::size() == 1 &&
                           UpIdx::size() == 1,
                       "wrong! inconsistent # of dimension");
-
+#if !Using_Gather
+        idx_diff_low(number<0>{}) = idx_diff_up[number<0>{}];
+#else
         int up_index              = idx_diff_up[number<0>{}] + pre_up_index_;
         int low_index             = *(cached_idx_ + up_index);
         idx_diff_low(number<0>{}) = low_index - pre_low_index_;
@@ -113,6 +118,7 @@ struct indexing_adaptor
                    idx_diff_up[number<0>{}],
                    idx_diff_low(number<0>{}));
         }
+#endif
 #endif
 
         // pass the diff to lower, but not changing the actually index