Re: [vhdl-200x-ft] Re: floating point, thinking out loud

David,
>> . . .
>> For example do I want more guard bits for a multiply than
>> for an add/subtract?
>
>
> Yes, you might want to do that. Originally we had the base package.
> Now that the base package is hidden we may want to break out
> add, subtract, and multiply the same way we do divide.

I liked (preferred) having the base package visible.
It seemed to be a nice saftey net. Perhaps we want
to keep it visible.

>> I suspect that if we define float, fp32, fp64 in a
>> separate package from fphdl_pkg, then if we instantiate
>> the package more than once (probably rare with the
>> modified interface) it will create homographs
>> of the operators and functions.
>
>
> That is why they are in the "fphdl_types_pkg" package. We
> still need it.

If you have this in a testable configuration, try out
referencing two packages in the same design and
using the type fp32.

>> I think we either need all of these types in the fphdl_pkg
>> or we need a float type in the types package and an
>> identically defined fp type in the fphdl_pkg. I think
>> this is similar to the package architecture you had before.
>
>
> Yes, but they are all one package now, the fphdl_types_pkg package.
> Thus we will no longer need to define them in the fphdl_pkg,
> in fact doing so would create a homograph.

Can you instantiate fphdl_pkg twice (to get different guard bit
sizes)? I was thinking that with the types in fphdl_types_pkg,
this would not be possible. I was thinking that the types
had to go in fphdl_pkg _instead of_ the fphdl_types_pkg.
In this case if two packages are references, then the type
names can be references by its selected name.

Cheers,
Jim

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