RE: Proposal for Updating CRC32C with AVX-512 Algorithm.

> The project is currently in feature-freeze in preparation for the next major
> release so new development and ideas are not the top priority right now.
> Additionally there is a large developer meeting shortly which many are busy
> preparing for. Excercise some patience, and I'm sure there will be follow-ups
> to this once development of postgres v18 picks up.

Thanks, understood.

I had our OSS internal team, who are experts in OSS licensing, review possible conflicts between the PostgreSQL license and the BSD-Clause 3-like license for the CRC32C AVX-512 code, and they found no issues. Therefore, including the new license into the PostgreSQL codebase should be acceptable.

I am attaching the first official patches. The second patch is a simple test function in PostgreSQL SQL, which I used for testing and benchmarking. It will not be merged.

Code Structure Question: While working on this code, I noticed overlaps with runtime CPU checks done in the previous POPCNT merged code. I was considering that these checks should perhaps be formalized and consolidated into a single source/header file pair. If this is desirable, where should I place these files? Should it be in "src/port" where they are used, or in "src/common" where they are available to all (not just the "src/port" tree)?

Thanks,
Paul