A width agnostic hash function

From: Clint Olsen (clint_at_0lsen.net)
Date: 03/30/04 

Date: Mon, 29 Mar 2004 22:19:22 GMT

Hello:

I've been doing reading on hash functions (with C implementations), and
I've noticed that all the techniques used have made certain assumptions
about the architecture width. You see specialized functions for 32-bit and
64-bit respectively. But can it be done in a way where sufficient mixing
is done where the width is either determined at runtime or dealt with in a
more general way?

Here are links to some relevant work performed thus far:

Jenkins:

http://burtleburtle.net/bob/hash/doobs.html

FNV:

http://www.isthe.com/chongo/tech/comp/fnv

Now that we're on the cusp of having quite a few 32 and 64-bit systems
deployed simultaneously, it seems like it might be worth the effort to have
functions which are not so dependent on the width of an unsigned long.

Thanks,

-Clint

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