Performance optimization for large arrays
Performance optimization for large arrays

Remove usage of uint128_t in tight loop. 40% performance gain.

Before:
```
   Method |        Median |     StdDev | PayloadLength |
--------- |-------------- |----------- |-------------- |
 FarmHash | 1,527.4707 ns | 17.0418 ns |         10000 |
```

After:
```
   Method |      Median |    StdDev | PayloadLength |
--------- |------------ |---------- |-------------- |
 FarmHash | 931.4246 ns | 2.5681 ns |         10000 |
```

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