Re: [myhdl-list] essay about integer arithmetic

[Jan D. <ja...@ja...>]

Michael Baxter wrote:
> Yes, but I intend for integers to represent fields of bits, and to do numerous
> other things that are not constrained by intervals. In fact, some of those
> things (involving plural, concurrent bitfields) can be done purely with
> conventional arithmetic operations. Normal integers, but not being used normally.
> 
> A 32-bit microprocessor (comprised of hardware) can have 32-bit registers that
> represent integers that are not signed, or that are signed, both at the same
> time. It all depends on what software does to interpret the meaning of those
> 32-bit register bits. What's the correct interval representation for the
> design of the registers in that hardware?

There is none. You use a bit vector in this case, design at the bit
level, and let the integer interpretation to software:

   a = intbv(0)[32:]

I hope it's clear from the essay that intbv is dual-mode type,
where you have the *option* to use it as a true integer if you want.
I realize that you suggest that such use cases don't exist. That
sounds absurd to me, but of course I've not only used Verilog
but also VHDL :-)

Jan

-- 
Jan Decaluwe - Resources bvba - http://www.jandecaluwe.com
    Python as a hardware description language:
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