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From: =?utf-8?Q?Dag-Erling_Sm=C3=B8rgrav?= <des@des.no>
To: Konstantin Belousov <kostikbel@gmail.com>
References: <506C385C.3020400@FreeBSD.org> <506DEB4C.5020508@andric.com>
	<86haq9hq2c.fsf@ds4.des.no>
	<20121005033244.GL35915@deviant.kiev.zoral.com.ua>
Date: Fri, 05 Oct 2012 09:08:35 +0200
In-Reply-To: <20121005033244.GL35915@deviant.kiev.zoral.com.ua> (Konstantin
	Belousov's message of "Fri, 5 Oct 2012 06:32:44 +0300")
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Cc: Dimitry Andric <dimitry@andric.com>, Andriy Gapon <avg@freebsd.org>,
	freebsd-arch@freebsd.org
Subject: Re: x86 boot code build
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Konstantin Belousov <kostikbel@gmail.com> writes:
> Dag-Erling Sm=C3=B8rgrav <des@des.no> writes:
> > Dimitry Andric <dimitry@andric.com> writes:
> > > Well, do we still officially support any real i386 machines?
> > No, 486 and up only.  Personally, I think we should ship 586
> > binaries (pentium-mmx) by default.
> There is absolutely no architectural difference between usermode ISA
> between i386 and pentiums, ignoring SMP-support instructions, which
> are usually not emited by the compiler anyway.

By "binaries" I mean ISOs and freebsd-update, including the kernel.

(actually, it's the kernel I care the most about)

> Really interesting stuff started appearing with pentium pro, like CMOV
> instructions. Even more important, -march=3Dpentiumpro generates much
> better -fPIC code (probably could be activated by -mcpu=3Dpentiumpro).

Which is why most Linux distributions target 686, but we can't if we
want to support small systems like the AMD Geode-based soekris net4xxx
and net5xxx out of the box.

DES
--=20
Dag-Erling Sm=C3=B8rgrav - des@des.no