Function block

tensorflow/core/kernels/eigen_contraction_kernel.h:415–445

        /*inner_dim_reordered=*/false, Alignment>;                             \
                                                                               \
    static bool block(const typename DataMapper::SubMapper& data_mapper,       \
                      const StorageIndex rows, const StorageIndex cols,        \
                      const StorageIndex num_kernels,                          \
                      ColMajorBlock<Scalar, StorageIndex>* block) {            \
      static_assert(DataMapper::DirectOffsets == true,                         \
                    "DataMapper must support direct offsets");                 \
                                                                               \
      const StorageIndex vert_offset = data_mapper.vert_offset();              \
      const StorageIndex horiz_offset = data_mapper.horiz_offset();            \
      const StorageIndex stride =                                              \
          Side == Lhs ? data_mapper.base_mapper().stride()                     \
                      : data_mapper.base_mapper().nocontract_strides()[0];     \
      const Scalar* data = data_mapper.base_mapper().tensor().data();          \
      data = Side == Lhs ? data : data + vert_offset + horiz_offset * stride;  \
                                                                               \
      const bool is_no_op_packing = stride == rows;                            \
      const StorageIndex addressable_mem = (stride * cols * sizeof(Scalar));   \
      const bool use_direct_access =                                           \
          is_no_op_packing || num_kernels == 1 /* used once */ ||              \
          ((num_kernels == 2) &&                                               \
           (addressable_mem < (256 << 10) /* 256 kb */));                      \
                                                                               \
      if (use_direct_access) {                                                 \
        block->is_direct_access = true;                                        \
        block->raw_data = const_cast<Scalar*>(data);                           \
        block->stride = stride;                                                \
        block->transpose = 'N';                                                \
        return true;                                                           \
      }                                                                        \
      return false;                                                            \
    }                                                                          \
  }

#define SIMPLE_TENSOR const Tensor<Scalar, 2, Eigen::ColMajor, StorageIndex>