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On Dec 6, 1:00*pm, Andy <jonesa...@comcast.net> wrote:
> I think I would use a function for the intermediate calculation, and
> then call the function in both concurrent assignment statements per
> the original implementation.
>
> Integers give you the benefits of bounds checking in simulation (even
> below the 2^n granularity if desired), and a big improvement in
> simulation performance, especially if integers are widely used in the
> design (instead of vectors).
>
> Andy

I know everyone says that integers run faster, but is this a
significant effect? Has it been measured or at least verified on
current simulators?

Rick

On Dec 6, 12:50*pm, rickman <gnu...@gmail.com> wrote:
> On Dec 6, 1:00*pm, Andy <jonesa...@comcast.net> wrote:
>
> > I think I would use a function for the intermediate calculation, and
> > then call the function in both concurrent assignment statements per
> > the original implementation.
>
> > Integers give you the benefits of bounds checking in simulation (even
> > below the 2^n granularity if desired), and a big improvement in
> > simulation performance, especially if integers are widely used in the
> > design (instead of vectors).
>
> > Andy
>
> I know everyone says that integers run faster, but is this a
> significant effect? *Has it been measured or at least verified on
> current simulators?
>
> Rick

A few years back, I had a design for a small FPGA with several modules
on a common bus. I started out with unsigned(4 downto 0) for the
address, and each module decoded its own address (each was given a
generic for address and size). Then I changed only that address to a
natural with equivalent range. Just that one change sped up my RTL
simulation from over 2.5 hours down to less than 1 hour. I considered
it very significant...

Andy