Function mutable_block_data

cpp/src/arrow/compute/key_map_internal.h:136–138

  }

  uint8_t* mutable_block_data(uint32_t block_id, int num_block_bytes) {
    return mutable_block_data(blocks_->mutable_data(), block_id, num_block_bytes);
  }

  static constexpr int kSlotsPerBlock = 8;