Re: always use runtime checks for CRC-32C instructions

On Tue, Oct 31, 2023 at 04:12:40PM -0400, Tom Lane wrote:
> Nathan Bossart <nathandbossart(at)gmail(dot)com> writes:
>> Okay. With that in mind, I think the path forward for new instructions is
>> as follows:
>
>> * If the special CRC instructions can be used with the default compiler
>> flags, we can only use newer instructions if they can also be used with
>> the default compiler flags. (My M2 machine appears to add +crypto by
>> default, so I bet your buildfarm animals would fall into this bucket.)
>> * Otherwise, if the CRC instructions can be used with added flags (i.e.,
>> the runtime check path), we can do a runtime check for the new
>> instructions as well. (Most other buildfarm animals would fall into this
>> bucket.)
>
> This seems like a reasonable proposal.

Great. I think that leaves us with nothing left to do for this thread, so
I'll withdraw it from the commitfest and move the discussion back to the
original thread.

--
Nathan Bossart
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