If the l-value is an unresolved wire, then elaboration can allow
the assignment as long as it is to bits that are not otherwise
driven. Handle this in some simple cases.
This gets nested l-values to (but just short of) the ivl_target API.
Now the elaborator can process nested l-values, but I haven't figured
out how to present that at the ivl_target.h API.
Static properties are like variables in a named scope.
Detect these variables during elaboration so that the
code generator just sees them as variables.
This implementation works by detecting assignments
to constant properties in elaboration. Allow initializer
assignments to assign to the constant, error all other
assignments, and otherwise treat the constant like any
other property.
For constant bit/part selects, issue a warning if the select is out
of range or an undefined value. In any case, the RHS value should be
discarded, and the actual assignment should be skipped.
For constant word indices, issue a warning if the index is out of
range or an undefined value. In any case, the RHS value should be
discarded, and the actual assignment should be skipped.
L-value bit selects were incorrectly converting an undefined index to 0.
L-value part selects were asserting if an undefined index was given.
This patch unifies how all these are handle (including indexed part selects).
The base is set to an undefined value and an appropriate width is used.
A warning message is always printed since this is not a simple out of
range issue. It is the responsibility of the code generator to skip the
assignment, but we always want to execute the R-value since it could have
a side effect.
Add properties to the classes, and elaborate expressions that
have class properties. Describe class object property references
all the way down to the stub target.
When string[x] is an l-value, generate code to implement something
like the string.putc(x, ...) method.
Also handle when string[x] is the argument of a system task. In that
case resort to treating it as a calculated 8-bit vector, because that
is what it is.
Stephen Williams
Cary R
Larry Doolittle
Martin Whitaker
Arun Persaud