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Re: [f-cpu] question to shifting unit

On Sat, Oct 13, 2001 at 01:32:48PM -0400, nicO wrote:
> To extract bit field we need to do a shift then a mask (so a 3r1w
> operation), it could be done using 2 instructions but 1 instruction will
> reduice the register bank pressure and maybe reduice the overall
> latency, the last stage will be a simple and.

It's better to do that with two shifts (instead of shift+mask) because you
can handle signed bit fields, too.  Besides that, the F-CPU instruction
format doesn't allow two immediate operands.

 Michael "Tired" Riepe <Michael.Riepe@stud.uni-hannover.de>
 "All I wanna do is have a little fun before I die"
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