Re: [RFC][2.5 patch] K6-II/K6-II: enable X86_USE_3DNOW

[Adrian Bunk <bunk@fs.tum.de>]

On Mon, Apr 14, 2003 at 06:36:20PM -0400, Robert Love wrote:
> On Mon, 2003-04-14 at 18:21, Adrian Bunk wrote:
> 
> > If my patch is wrong and this is a RTFM please give me a hint where to 
> > find the "M".
> 
> Patch looks right...
> 
> > Questions:
> > Is it really correct to enable CONFIG_X86_USE_3DNOW?
> 
> If you are right that the K6-2 and K6-3D support 3DNow!, then yes.  At
> least its "correct" but it may not be optimal: I seem to recall 3DNow
> memory copies were not worthwhile on anything before an Athlon.  Double
> check that, though.

It does, but Alan already explained why it doesn't make a difference.

> > Is the -march=k6-2 correct?
> 
> Yes.  Even if the above is true, splitting the K6 out like this is
> useful for the extra -march here.  It certainly does not hurt (picking
> the original K6 will give proper support for the whole family, in
> needed).

>From a quick look of the gcc-3.2.2 sources it seems that except for the 
3DNow! support gcc doesn't differenciate between K6 and K6-II, so this 
change alone doesn't seem to make it worth adding a new processor type.

> 	Robert Love

cu
Adrian

-- 

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       "Only a promise," Lao Er said.
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