message: some documentation improvements
diff: @@ -97,7 +97,11 @@ struct row_major_helper_s<ValueType, total_dim, total_dim> {
  /**
  * Computes the storage index for the given indices with respect to the given
  - * stride array
  + * stride array for row-major access
  + *
  + * @param size the multi-dimensional sizes of the range of values
  + * @param stride the stride array
  + * @param idxs the multi-dimensional indices of the desired entry
  */
  template <typename ValueType, size_type total_dim, typename... Indices>
  constexpr GKO_ATTRIBUTES ValueType compute_storage_index(
  @@ -639,13 +643,14 @@ namespace detail_block_col_major {
  /**
  - * This helper runs from first to last dimension in order to compute the index.
  + * Runs from first to last dimension in order to compute the index.
  + *
  * The index is computed like this:
  * indices: x1, x2, x3, ..., xn
  * compute(stride, x1, x2, x3, ..., x(n-1), xn) ->
  * x1 * stride[0] + x2 * stride[1] + ...
  * + x(n-2) * stride[n-3] + x(n-1) + xn * stride[n-2]
  - * Note that swap of the last two strides, making this 'column major'.
  + * Note that swap of the last two strides, making this 'block column major'.
  */
  template <typename ValueType, size_type total_dim, size_type current_iter = 1>
  struct index_helper_s {
  @@ -695,8 +700,11 @@ struct index_helper_s<ValueType, total_dim, total_dim> {
  };
  /**
  - * Computes the storage index for the given indices with respect to the given
  - * stride array
  + * Computes the flat storage index for block-column-major access.
  + *
  + * @param size the multi-dimensional sizes of the range of values
  + * @param stride the stride array
  + * @param idxs the multi-dimensional indices of the desired entry
  */
  template <typename ValueType, size_type total_dim, typename... Indices>
  constexpr GKO_ATTRIBUTES ValueType compute_index(
  