Re: optimize lookups in snapshot [sub]xip arrays

On Wed, Aug 03, 2022 at 11:06:58AM -0700, Andres Freund wrote:
> On 2022-08-02 16:43:57 -0700, Nathan Bossart wrote:
>> >> +#ifdef USE_SSE2
>> >> +pg_attribute_no_sanitize_alignment()
>> >> +#endif
>> > 
>> > What's the deal with this annotation? Needs a comment.
>> 
>> Will do.  c.h suggests that this should only be used for x86-specific code.
> 
> What I'm asking is why the annotation is needed at all?

Upon further inspection, I don't think this is needed.  I originally
borrowed it from the SSE version of the CRC code, but while it is trivial
to produce alignment failures with the CRC code, I haven't been able to
generate any with my patches.  Looking at the code, I'm not sure why I was
worried about this in the first place.  Please pardon the brain fade.

Here is a new patch set without the annotation.

-- 
Nathan Bossart
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