Re: [myhdl-list] MEP - keep hierarchy in conversion

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

On 10/02/2013 10:11 AM, Per Karlsson wrote:
> Enforcing "top-level convertibility" at all levels of the design
> would be a huge step backwards for MyHDL.

Obviously, with the user-defined code approach top-level convertibility
would only be needed at those levels where you want a hierarchical
partioning point. For an application such as floorplanning, this
would presumably be at a limited number of places close to the
top-level.

Furthermore, it is not at all obvious to me that "virtual" top-level
convertibility would not be required for the other proposed
approaches also.

> Encapsulating target dependent design is standard practice, but the
> netlist hierarchy is not part of that---mostly. :)

The hierarchy is in the MyHDL design - the question is how
to extract it (or an alternative one) to the converted output.

I am not discussing the concept now, but David's proposed method.
Let's make this practical. If I understand David's solution,
one would define a desired output partition by significant,
non-functional changes to the source code.

Suppose someone does this for his requirements, and later you
inherit that IP block. Now suppose you need a different kind of
partitioning - your only option would be to make significant,
non-functional changes (hopefully) to the source code.

Do you really want that?

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