26 void gather_block_distribution_info(MPI_Comm comm,
const int64_t local_block_size,
const int64_t global_block_size,
int64_t* block_displs ,
int** block_owner_table_ptr ,
int64_t** block_owner_cutoff_ptr ,
int* lg_minblocksize_ptr,
int64_t* maxblocksize_ptr);