Saturday, July 04, 2020

Re: strlcpy version speed tests?

>> On Jul 1, 2020, at 1:14 PM, gwes <gwes@oat.com> wrote:
>>
>> On 7/1/20 8:05 AM, Luke Small wrote:
>> I spoke to my favorite university computer science professor who said
>> ++n is faster than n++ because the function needs to store the initial
>> value, increment, then return the stored value in the former case,
>> while the later merely increments, and returns the value. Apparently,
>> he is still correct on modern hardware.
> For decades the ++ and *p could be out of order, in different
> execution units, writes speculatively queued, assigned to aliased registers,
> etc, etc, etc.
>
> Geoff Steckel

Hey Luke,

I love the passion but try to focus your attention on the fact that their are multiple architectures supported and compiler optimizations are key here. Go with Marc's approach using arch/ asm. Implementations can be made over time for the various arch's, if such an approach is desirable by the project. You can pull a well-optimized version based on your code, for your arch, and then slim it down a bunch.

Cheers,
Brian

[Not a project developer. Just an observer.]

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