Horton

Re: Popcount optimization using AVX512

David Rowley <dgrowleyml@gmail.com>

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From: David Rowley <dgrowleyml@gmail.com>
To: "Amonson, Paul D" <paul.d.amonson@intel.com>
Cc: Nathan Bossart <nathandbossart@gmail.com>, Andres Freund <andres@anarazel.de>, Alvaro Herrera <alvherre@alvh.no-ip.org>, "Shankaran, Akash" <akash.shankaran@intel.com>, Noah Misch <noah@leadboat.com>, Tom Lane <tgl@sss.pgh.pa.us>, Matthias van de Meent <boekewurm+postgres@gmail.com>, "pgsql-hackers@lists.postgresql.org" <pgsql-hackers@lists.postgresql.org>
Date: 2024-03-20T04:26:07Z
Lists: pgsql-hackers

Commits

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  1. Fix __attribute__((target(...))) usage.

  2. Use __attribute__((target(...))) for AVX-512 support.

  3. Fix code for probing availability of AVX-512.

  4. Optimize visibilitymap_count() with AVX-512 instructions.

  5. Optimize pg_popcount() with AVX-512 instructions.

  6. Inline pg_popcount() for small buffers.

  7. Avoid function call overhead of pg_popcount() in syslogger.c.

  8. Refactor code for setting pg_popcount* function pointers.

  9. Inline pg_popcount{32,64} into pg_popcount().

  10. Remove MSVC scripts

  11. Use ARMv8 CRC instructions where available.

  12. Use Intel SSE 4.2 CRC instructions where available.

On Wed, 20 Mar 2024 at 11:56, Amonson, Paul D <paul.d.amonson@intel.com> wrote:
> Changed in this patch set.

Thanks for rebasing.

I don't think there's any need to mention Intel in each of the
following comments:

+# Check for Intel AVX512 intrinsics to do POPCNT calculations.

+# Newer Intel processors can use AVX-512 POPCNT Capabilities (01/30/2024)

AMD's Zen4 also has AVX512, so it's misleading to indicate it's an
Intel only instruction.  Also, writing the date isn't necessary as we
have "git blame"

David