Re: Good hash for pointers

Am 26.05.2024 um 18:24 schrieb Tim Rentsch:

Bonita Montero <Bonita.Montero@gmail.com> writes:
 

Am 25.05.2024 um 19:40 schrieb Tim Rentsch:
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Bonita Montero <Bonita.Montero@gmail.com> writes:
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Am 25.05.2024 um 11:12 schrieb Tim Rentsch:
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Your hash function is expensive to compute, moreso even
than the "FNV" function shown earlier.  In a case like
this one where the compares are cheap, it's better to
have a dumb-but-fast hash function that might need a
few more looks to find an open slot, because the cost
of looking is so cheap compared to computing the hash
function.

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A (size_t)pointer * LARGE_PRIME can be sufficient,
ignoring the overflow.

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Plenty fast but the output quality is poor. ...

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If the prime is large enough there'e no regular distribution.

 Your conjecture is contradicted by empirical facts.

There are no empirival facts for that since two times the
taken prime is beyond the 64 bit address space.