Re: [myhdl-list] MyHDL code clean-up - please review

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

I have just pushed the latest changes that implement everything
as described below.

Every leaf block in the structure should now use a decorator,
if you want to do things like tracing signals and conversion.
This introduces a small backwards incompatibility (probably
mostly for my own older unit tests) but simplifies the
implementation tremendously. Code using decorators is also
clearer as to its purpose.

If you see a problem (e.g. "no instances found") with older
code, the workaround should be easy: use a @instance decorator.

Regards,

Jan

Jan Decaluwe wrote:
> I think the introduction of decorators in MyHDL 0.5 has been
> a success, and by now everybody uses them.
> 
> For pure modelling, you can construct generators in any way,
> including directly without decorators, and that will always
> remain so.
> 
> However, some more implementation-oriented features, such
> as hierarchy extraction, signal tracing and conversion also
> contain support for non-decorator generators. This complicates
> the code considerably, and in my opinion, unnecessarily.
> Before adding new features, I would like to remove this
> support to simplify the code.
> 
> Again, if you use decorators, everything should continue to
> work as before. Below I will describe the proposed changes
> in detail. Please review and give feedback about any objection.
> 
> * remove 'processes' function
> This (undocumented) function is obsolete if you use decorators. It
> was deprecated in 0.5.
> 
> * change 'instances' function to only return generators from decorators
> Currently 'instances' returns any kind of generator. Sometimes people
> may want to use a generator for other purposes than hardware description:
> currently you can't use 'instances' in that case. By only returning
> generators from decorators, this would become possible.
> 
> * remove support for "top-level" generators
> 
> Consider the degenerated case where the top-level is a generator:
> 
> def top():
>     <generator_body>
> 
> Hierarchy extraction, signal tracing and conversion have some special
> support for this, which I would like to remove. Note that the
> above is equivalent to:
> 
> def top():
>      @instance
>      def logic():
>          <generator_body>
>      return logic
> 
> * in general, assume that for hierarchy extraction, signal tracing
> and conversion, only generators from decorators need to be considered.
> There may be some more places in the code where this assumption can help
> to simplify things.
> 
> 
> Jan
> 


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