FAst NOn-Multiplicative hash :-)
fanom_hash.h contains fast non-multiplicative function for 64bit processor. It passes whole SMHasher.
It is not "fastest function in a world":
- SpookyHash is also non-multiplicative, and it is faster for long strings. But it uses 12 64bit variable and has huge code.
- there is bunch of multiplicative hashes that are faster, (to be fair, SpookyHash is as fast on long strings).
- functions on top of hardware AES and CRC are fastest. (AES ones: Golang x86_64 assembler function, and falkhash).
But performance of fanom64 is comparable, and it is better than Murmur3_x64 So if you need crossplatform and relatively simple function, which works fast despite of absence of fast multiplication or "hardware permutation" instructions, then this function is suitable for you :-).
fanom_hash32.h contains 32bit variant that produce 32bit output. Its performance 2 times better than murmur3_32, it is better than Murmur3_x32_128, and just slightly slower than Murmur3_x64. So, fanom32 is a good function, if you need fast crossplatform hash function which not relies and 64bit arithmetic.
I argued against @ticki ( https://github.com/ticki ) it has no seed independent collision. If it has I will give @ticki 50$. If it hasn't, @ticki will write a blog post about this function.
For the argue, test_fanom.c is written. It reads a seed from /dev/urantom, then it reads stdin line by line and inserts it into simple chained hash table.
If there is a file with strings that leads to notable performace degradation compared to random strings, then I loose.
Copyright 2016 Sokolov Yura aka funny-falcon.