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From: Jeff Davis <[email protected]>
To: Tom Lane <[email protected]>
To: Nathan Bossart <[email protected]>
Cc: [email protected]
Cc: [email protected]
Subject: Re: always use runtime checks for CRC-32C instructions
Date: Mon, 30 Oct 2023 13:48:29 -0700
Message-ID: <[email protected]> (raw)
In-Reply-To: <[email protected]>
References: <20231030161706.GA3011@nathanxps13>
	<[email protected]>

On Mon, 2023-10-30 at 12:39 -0400, Tom Lane wrote:
> It seems like a shame
> to be burdening these instructions with a subroutine call for the
> benefit of long-obsolete hardware versions.

It's already doing a call to pg_comp_crc32c_sse42() regardless, right?

I assume you are concerned about the call going through a function
pointer? If so, is it possible that setting a flag and then branching
would be better?

Also, if it's a concern, should we also consider making an inlineable
version of pg_comp_crc32c_sse42()?

Regards,
	Jeff Davis

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