[Gllug] Re: Dual core AMDs

[Adrian McMenamin]

On Thu, 2005-07-14 at 23:14 +0100, Robert Newson wrote:
> Christian Smith wrote:
> 
> ...
> > Ah, but it did save a branch instruction, which was at least 2 (3?) cycles
> > per loop. There was non of this modern pipelining technology back then,
> > you know(*).
> 
> According to my book, on a Z80 a JR cc takes 12/7 cycles - 12 if branch 
> taken, 7 if not.
> On a 6502 a Bcc takes 2/3(/4) cycles - 2 if not taken, 3 if taken (+ an 
> extra cycle if a page boundary crossed IIRC).
> 

To be honest, although I started all this Z80 v 6502 stuff, I don't
believe there is any serious evidence that one was faster than the other
across the range of real world applications.



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