Since the vlog95 code generator needs the strength information we do
not want to hide it behind a concat-Z optimization. For now we abort
the optimization, but in the future we could add parts of this back
in (e.g. all the drivers have matching strength then replace with a
normal concat and a buf-Z if the strength are not both strong. The
original buf-Z should be removed to reduce the number of LPM devices).
This is the initial commit in an effort to build a 1364-1995
back end for Icarus Verilog. It is expected that this back end
will allow the user to write 1364-2005 RTL and then using this
back end (converter) generate functionally equivalent 1364-1995
compatible code. This can be used to support older tools in a
work flow. The primary focus will be simulation equivalence,
though I expect to verify logical equivalence as well.
Cary R