When a signal (or port) is assigned by a sequential assignment,
the signal or port becomes a reg, instead of a wire(net). Detect
this distinction during elaboration and generate the correct
signal/port declaration.
R-value expressions are more general then L-value expressions, in that
the expression type may be a bit more complex. If the R-value expression
is part of an assignment, then elaborate with the constrained type from
the L-value. In other cases, where the expression type is not as obvious,
use expression type probes to figure out the type of the expression and
elaborate using that calculated type.
There has been added additional default attribute to
all 'dump' function calls which is in all cases equal
to 0. Now one can specify how much this debug dumping should
be intended. This should allow people to dump smoothly whole
designs (as it was now) as far as separate units.
This is now the parent who specifies the base indentation
for all components (children). For example, architecture
"decides" how much their signals should be indented.
These signals are declared in the architecture and are local to
the module. The Architecture already parsed and stored these signal
declarations, but this patch adds the ability to actually emit these
signals in the generated code.
In the process of doing this, I had to regularize the elaboration
and emit of VTypes, so that it can be used in multiple places, not
just in entity headers (for ports).
I also added support for bit selects of signals. This effected a couple
places in the parser, and expressions in general.
These go into the architecture/block of their scope and will be
used by component instantiations to make sure the bindings are
correct and complete.
Also handle signal declarations. The elaborator will use these
to generate module local variables that are used by the architecture.