Re: TI-H: Power PC


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Re: TI-H: Power PC




Just like I can show you a programming example in which CISC is just as fast
as RISC.  If you're going to bring it up, mention details.  The essence of
CISC is to make an instruction for everything.  Even though a multiply is just
a loop of additions, it'll still have an instruction for it.  This goes for a
lot of other ops.  However, by doing this, you add another layer of
complexity, since each instruction is of a different length.
    In RISC, you have fewer instructions, and your compiler will break down
the complex code into simpler instructions, which are each the same length.
As a result, each one is processed the same way, and you can even do more than
one at a time more easily, because they all come back at just about the same
time, and you piece the results back together.  CISC is highly dependent on
instruction order, and it's a miracle that the dual-pipe Pentium and up CPUs
were even created.
    By the way, the multiply example was only used for simplicity.  I'm pretty
sure that most modern RISC processors HAVE a dedicated multiply instruction...

CK

Grant Stockly wrote:

> Just by hearing the name PowerPC, you know its better than any Intel or
> compatible.  The PPC uses RISC technology (~4 years old) and the intel
> processors use CISC technology (~22 years old).  For one thing, the C
> stands for complicated and the R stands for reduced.  If you want, I can
> show you a programming example for each in machine code and you can see
> which can do the same process faster.




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