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Re: in_cksum (Re: CVS commit: [yamt-lazymbuf] src/sys/arch/amd64/include

Subject: Re: in_cksum Re: CVS commit: [yamt-lazymbuf] src/sys/arch/amd64/include
From: Joerg Sonnenberger
Date: Sat, 09 Feb 2008 13:10:58 UTC
Newsgroups: fa.netbsd.tech.net

On Sat, Feb 09, 2008 at 09:48:56PM +0900, YAMAMOTO Takashi wrote:
> btw, according to regress/sys/net/in_cksum, i386 asm version
> (cpu_in_cksum.S 1.2) seems slower than portable version
> on my cpu.

Actually, I'm not surprised by that. Given that the inner loop is using
adc all the time, the adds themselve can't run in parallel. I haven't
had time to carefully analyse the code if the amd64 could be ported.

Joerg

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