Re: [PATCH 0/7] pack-objects: Create an alternative name hash algorithm (recreated)

From: Jonathan Tan <jonathantanmy@google.com>
Date: Nov 22, 2024, 18:05 UTC
Message-ID: <20241122180530.530499-1-jonathantanmy@google.com>
In-Reply-To: <xmqqiksgas54.fsf@gitster.g>

Junio C Hamano <gitster@pobox.com> writes:

Show 7 quoted lines

> I wonder if we do even better if we reverse all 8 bits instead of
> swapping nybbles (if we were to do so, it might be more efficient to
> shift in from the right instead of left end of the base and hash
> accumulators in the loop and then swap the whole resulting word at
> the end).
> 
> Thanks for a fun read.

Ah, yes, reversing is better than swapping nybbles (the least significant 2 bits have more entropy than the next-least significant 2 bits). When writing this, I didn't think of shifting in from the right (if I had thought of that, I would have indeed reversed the bits instead).

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