From:	"Tom ST Denis" <tstdenis3160 AT home DOT com>
Newsgroups:	comp.os.msdos.djgpp
Subject:	Support for higher end cpus
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Date:	Sun, 31 Dec 2000 01:29:47 GMT
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I know (from my earlier post) that DJGPP can understand switches such
as -march=k6 or -march=i686 but the code it produces doesn't seem to be any
faster (substantially anyways) then -march=i486.  The output code *is*
different just not improved.

My basis for this judgement is my compilation of Allegro and my updated
Plush lib.  I get about the same FPS in my Plush examples when I use
march=k6 (on my Athlon) then I do with march=i486.

Will there be any development for supporting the K7/PIII/PIV?  It would make
DJGPP (and it's GCC derivatives such as CYGWIN) jump way ahead of VC++ 6.0.
If GCC supported these new cpus I bet alot of people would be happy!  I know
I would.

For the most part I think just the way the code is rescheduled is the only
thing the compiler *could* do.  But often that makes a big difference.
Other things such as MMX/3dNOW instructions could be provided by a libext.a
or something that is optional for a DJGPP installation.

I have no clue about compiler development or serious optimization tricks.  I
just use the compiler and write what I think is efficient algorithms... so I
can't help develop this...wish I could..

Thanks,
Tom

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