The natures of disciplines were already available, this just brings
the information forward to the ivl_target.h API and exposes them via
access functions.
Signals may have VMA disciplines attached. Make the attached discipline
visible through the ivl_target.h API. Also, re-arrange the internal
handling of the discipline structure so that we can expose disciplines
through the ivl_target C API without creating new structures. The
t-dll-api implementations of the discipline access functions can look
at the elaborated discipline structure directly. This is possible since
the discipline parse and elaboration are very simple.
The NetBranch object is connected, but not like an object, so the
NetPins object base class is factored out from NetObj to handle the
connectivity, and the NetBranch class uses the NetPins to connect a
branch.
Also, account for the fact that nets with a discipline are by default
real-valued.
Detect function call expressions that turn out to be calls to the
access function of a nature. Elaborate the access function and stub
the emit code. This gets the access function just short of the code
generator.
Pform parse enough of the natures that they can be mapped and the
disciplines can bind to them. Since Verilog-AMS expects natures to
be declared before use, we can do the binding early.
Parse discipline declarations, net discipline declarations, and
analog contribution statements. Don't yet do anything useful with
these, just give a sorry message where they are encountered.
Stephen Williams
Larry Doolittle