Use wyhash for <til/hash.h> - #13686
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Hello Leonard Hecker (@lhecker)! Because this pull request has the p.s. you can customize the way I help with merging this pull request, such as holding this pull request until a specific person approves. Simply @mention me (
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wyhash was chosen based on the results found in
smhasher, were it proveditself as an algorithm with little flaws and fairly high output quality.
While I have a personal preference for xxhash (XXH3 specifically), wyhash is a
better fit for this project as its source code is multiple magnitudes smaller,
simplifying the review and integration into the header-only
hash.hfile.For use with hashmaps the hash quality doesn't actually matter much for
optimal performance and instead the binary size usually matters more.
But even in that scenario wyhash is fairly close to FNV1a (aka "FNV64").
The result is that this new hash algorithm will only have little impact on
hashmap performance if used over the standard FNV1a as used in the STL,
while simultaneously offering a vastly better hash quality.
This partially solves #13124.
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