Re: add AVX2 support to simd.h

Nathan Bossart <nathandbossart@gmail.com>

From: Nathan Bossart <nathandbossart@gmail.com>

To: Tom Lane <tgl@sss.pgh.pa.us>

Cc: John Naylor <johncnaylorls@gmail.com>, Ants Aasma <ants@cybertec.at>, pgsql-hackers@postgresql.org

Date: 2024-03-27T21:37:35Z

Lists: pgsql-hackers

Commits

Same data as JSON: GET /api/v1/messages/:b64id/commits the thread's linked commits as JSON, with link sources. API reference →

Improve style of pg_lfind32().
- 7188a7806d20 17.0 landed
Fix compiler warning for pg_lfind32().
- 1f42337be535 17.0 landed
Micro-optimize pg_lfind32().
- 7644a7340c8a 17.0 landed
Introduce helper SIMD functions for small byte arrays
- 9f225e992bed 17.0 cited
Optimize xid/subxid searches in XidInMVCCSnapshot().
- 37a6e5df3713 16.0 cited

Attachments

v2-0001-improve-style-of-pg_lfind32.patch (text/x-diff)

On Wed, Mar 27, 2024 at 05:10:13PM -0400, Tom Lane wrote:
> Shouldn't "i" be declared uint32, since nelem is?

Yes, that's a mistake.

> BTW, I wonder why these functions don't declare their array
> arguments like "const uint32 *base".

They probably should.  I don't see any reason not to, and my compiler
doesn't complain, either.

> LGTM otherwise, and I like the fact that the #if structure
> gets a lot less messy.

Thanks for reviewing.  I've attached a v2 that I intend to commit when I
get a chance.

-- 
Nathan Bossart
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