Function BitmapWordReaderBench

cpp/src/arrow/util/bitmap_reader_benchmark.cc:78–108

}

static void BitmapWordReaderBench(benchmark::State& state) {
  int64_t nbytes = state.range(0);
  std::shared_ptr<Buffer> cond_buf = CreateRandomBuffer(nbytes);
  for (auto _ : state) {
    BitmapWordReader<uint64_t> counter(cond_buf->data(), 0, nbytes * 8);

    int64_t set_bits = 0;

    int64_t cnt = counter.words();
    while (cnt--) {
      const auto& word = counter.NextWord();
      //      if (word == UINT64_MAX) {
      //        set_bits += sizeof(uint64_t) * 8;
      //      } else if (word) {
      //        set_bits += std::popcount(word);
      //      }
      set_bits += std::popcount(word);
      benchmark::DoNotOptimize(set_bits);
    }

    cnt = counter.trailing_bytes();
    while (cnt--) {
      int valid_bits;
      const auto& byte = static_cast<uint32_t>(counter.NextTrailingByte(valid_bits));
      set_bits += std::popcount(kPrecedingBitmask[valid_bits] & byte);
      benchmark::DoNotOptimize(set_bits);
    }
    benchmark::ClobberMemory();
  }
  state.SetBytesProcessed(state.iterations() * nbytes);
}

BENCHMARK(BitBlockCounterBench)->Arg(kBufferSize);
BENCHMARK(BitmapWordReaderBench)->Arg(kBufferSize);