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@gmail.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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