Function block_id_from_hash

cpp/src/arrow/compute/key_map_internal.h:108–110

                                     uint32_t group_id);

  static uint32_t block_id_from_hash(uint32_t hash, int log_blocks) {
    return hash >> (bits_hash_ - log_blocks);
  }

  static uint32_t global_slot_id(uint32_t block_id, uint32_t local_slot_id) {
    return block_id * kSlotsPerBlock + local_slot_id;