[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: Rep:Re: [f-cpu] Manual 0.2.6
On Sun, Aug 04, 2002 at 09:21:38PM +0200, cedric wrote:
[... cshift instruction...]
> I think you are right, because we have the mix/expand instruction. Currently
> we must do something like this for 8 bits :
> mixl.b r1, r2, r9
> mixl.b r3, r4, r10
> mixl.b r5, r6, r11
> mixl.b r7, r8, r12
> mixl.d r9, r10, r13
> mixl.d r11, r12, r14
> mixl.q r13, r14, r15
Right.
> 7 cycles for 8 chunks, that's quite good. So no need of a more complex
> instruction for small chunk and the cshift[l/r] will be enough (perhaps a
> immediate version will be usefull).
An immediate version (cshift[rl]i) is not a problem.
I think an `arithmetic' right shift (cshiftra) is not useful; but what
about rotates (crotl/crotr)?
--
Michael "Tired" Riepe <Michael.Riepe@stud.uni-hannover.de>
"All I wanna do is have a little fun before I die"
*************************************************************
To unsubscribe, send an e-mail to majordomo@seul.org with
unsubscribe f-cpu in the body. http://f-cpu.seul.org/