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Re: [f-cpu] Status quo

Hi Ralf,

On 03/28/2015 03:03 PM, Ralf Jonas wrote:
Hi Yann,

 > No BCD there either, it's pure binary again.
please name ?

well, let me explain: The last 15 years we programmed a large java
application for an advertising company. Our programms have to plan
advertising campaigns and the distribution of budgets. Budgets in size
up to 1.500.000.000,-- â

Because our programm was strictly forbidden to have any rounding
differences, our main datatype was java.lang.BigDecimal. To avoid any
side effects from the database, we even stored the values as strings.

I already told you, I'm a programmer, not a cpu designer. So I just
thought I might be handy, if the cpu could calculate decimal values
directly. You're right: Of course it's possible to do all that decimal
stuff with standard integer arithmetic. 100% agree.

But I couldn't imagine, that a decimal arithmetic unit would be that
complicated. It's just from my point of view as a programmer...

There are software libraries implementing arbitrary precision
arithmetics like libgmp, and they're ported to all major architectures,
including those that don't implement BCD in hardware. So this shouldn't
be a concern.

Kind regards,
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