Re: [myhdl-list] intbv.wrap()

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

On 04/18/2011 08:23 PM, Christopher Lozinski wrote:
> Thank you to Tom Dillon and to Chris Felton for explaining the wrapping
> stuff.  It took me forever to understand it.  Now I know why.
>
> I totally understand how hardware engineers would want to do that.  But
> for the software engineer, it is a terrible idea.  Different people
> really do see the world differently.

Terrible? Ada has modular types. They wrap around.

> As a software guy I just want a 32 bit integer that yields an error
> condition when it overflows.  That is what I expect.  And of course if
> it is made up of a sign object and a mantissa so much the better.

Really? Python doesn't have 32 bit integers that yield an overflow
error. If you want that, tryintbv(0)[32:].

> I am not trying to change the intbv library.  It is perfect for its
> users.  I am just pointing out that we software engineers see the world
> differently from the hardware engineers.

As my counter-examples show, many software engineers apparently see
the word differently from you. Let's sort that out, before even
starting with the hardware engineers.

>  So maybe eventually there can
> be two different integer libraries, with different models behind them,
> and maybe different users.  Those building application specific circuits
> would use one, those building generic microprocessors could use the other.

I don't see what good this would do for these cases. Both users
are hardware designers for which hardware efficiency is probably
a crucial cost factor, especially for those building generic
microprocessors.

-- 
Jan Decaluwe - Resources bvba - http://www.jandecaluwe.com
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