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From: Tim Rentsch <tr.17687@z991.linuxsc.com>
Newsgroups: comp.lang.c
Subject: Re: Good hash for pointers
Date: Sun, 26 May 2024 09:24:58 -0700
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Bonita Montero <Bonita.Montero@gmail.com> writes:

> Am 25.05.2024 um 19:40 schrieb Tim Rentsch:
>
>> Bonita Montero <Bonita.Montero@gmail.com> writes:
>>
>>> Am 25.05.2024 um 11:12 schrieb Tim Rentsch:
>>>
>>>> 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.
>>>
>>> A (size_t)pointer * LARGE_PRIME can be sufficient,
>>> ignoring the overflow.
>>
>> Plenty fast but the output quality is poor. ...
>
> If the prime is large enough there'e no regular distribution.

Your conjecture is contradicted by empirical facts.