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arXiv · 1503.03465

Faster 64-bit universal hashing using carry-less multiplications

Daniel Lemire·Owen Kaser
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Abstract

Intel and AMD support the Carry-less Multiplication (CLMUL) instruction set in their x64 processors. We use CLMUL to implement an almost universal 64-bit hash family (CLHASH). We compare this new family with what might be the fastest almost universal family on x64 processors (VHASH). We find that CLHASH is at least 60% faster. We also compare CLHASH with a popular hash function designed for speed (Google's CityHash). We find that CLHASH is 40% faster than CityHash on inputs larger than 64 bytes and just as fast otherwise.

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Daniel Lemire, Owen Kaser. 2015-11-04. Faster 64-bit universal hashing using carry-less multiplications. https://doi.org/10.1007/s13389-015-0110-5

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