Re: [gentoo-user] Re: i486

[David W Noon]

On Tue, 23 Nov 2010 22:10:02 +0100, Neil Bothwick wrote about Re:
[gentoo-user] Re: i486:

>On Tue, 23 Nov 2010 18:36:49 +0000, David W Noon wrote:
>
>> >CFLAGS="-O2 -march=geode -pipe -fomit-frame-pointer"
>> >CXXFLAGS="${CFLAGS}"
>> >CHOST="i486-pc-linux-gnu"
>>
>> Try using i686 instead.
>>
>> >flags           : fpu de pse tsc msr cx8 pge cmov mmx mmxext
>> >3dnowext
>>
>> You have CMOV and MMX, as well as 3DNow! instructions -- with
>> extensions. That makes it an Athlon "lite" processor, or a K6-3 with
>> CMOV instructions.  These are enough to make it compatible with the
>> Pentium Pro (i686) architecture, and a bit more besides.
>
>Apparently it's not quite a full i686. The research I did at the time
>indicated that using anything higher than i486 was asking for problems.

I am a little surprised by that.  I ran a couple of K6-3 boxes for some
few years using i586.  As near as I could tell, those processors only
lacked CMOV instructions when compared with i686.  I find it hard to
envisage the Geode lacking any i586 feature, given that it has MMX
instructions, CMOV instructions, the CMPXCHG8B instruction and a TSC
register -- all of those are way beyond i486.
-- 
Regards,

Dave  [RLU #314465]
*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*
dwnoon@××××××××.com (David W Noon)
*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*-*