Re: improvement of index-calculation

From: "Guenther Wimpassinger" <gw_spam@xxxxxxxxx>
Date: Wed, 27 Jul 2005 20:47:55 +0200

"Les Pawelczyk" <les_at_pixelpointpos_dot_com> schrieb

> > bt EAX,EBX
> > lahf
> > xchg AL,AH
> > and EAX,$1
>
> bt eax, ebx
> setc al
>
Hi!

mov ECX,EBX
shr EAX,CL

and EAX,$1

seems to be faster then the bt/setc combination.
at least on my computer (Intel P4)

thanks anyway
Guenther

.

References:
- improvement of index-calculation
  - From: Guenther Wimpassinger
- Re: improvement of index-calculation
  - From: Guenther Wimpassinger
- Re: improvement of index-calculation
  - From: Guenther Wimpassinger
- Re: improvement of index-calculation
  - From: Les Pawelczyk

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