Re: Managing 64-bit numbers in VB6

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From: Jacky Luk (jl_at_knight.com)
Date: 05/27/04 

Date: Thu, 27 May 2004 09:20:16 +0800

Hi Duane,
Yes, we had considered outsourcing, but this project is very urgent. So we
have to do it later. Anyway thanks for your great help. We appreciate it!

Please let me ask another question, considering that floating point
calculations are simpler than MMX ones. How about floating point
calculations on VB6? If I check the favor Pentium Pro ?? checkbox, can we
get to the floating point instructions?
Thanks
Jack

"Duane Bozarth" <dp_bozarth@swko.dot.net>
???????:40B37A9F.E68E3449@swko.dot.net...
> Duane Bozarth wrote:
> >
> > Jacky Luk wrote:
> > >
> > > Dear all,
> > > I am not sure if VB6 supports MMX instructions. As I have written a
hermite
> > > function, and it requires MMX,
> > > my question is how to tell VB6 to start using MMX instructions in my
> > > program. Thanks
> > > Jack
> >
> > How did you manage to write a VB function that "requires" MMX?
> >
> > Don't know if VB will generate MMX instructions or not, but best chance
> > of it would be to set the "favor Pentium Pro" switch...then you'll have
> > to check the generated code to see if it actually did generate MMX
> > instructions as there is no documentation I know of that actually says
> > what the switch actually does/doesn't do...
> >
> > If you're really into needing to control this level of code generation
> > you really need to be using tools other than VB. I reiterate my
> > previous suggestion that you seriously consider getting an outside
> > expert to evaluate your situation and provide help where your team is
> > lacking expertise. It will be far cheaper in the long run, I'd wager...
>
> And, there are quite a few sites that show how to mix ass'y w/VB altho
> it would be far simpler to write the code in C/C++ where you can control
> the code generation and call it from VB.
>
> Do a google on "MMX + VB" to find at least a couple of examples...but
> they'll not be easy if you don't understand ass'y.

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