def singleDriver(self):
"""
Returns a first driver if signal has only one driver.
"""
d_cnt = len(self.drivers)
if d_cnt == 0:
raise SignalDriverErr([
(SignalDriverErrType.MISSING_DRIVER, self),
])
elif d_cnt > 1:
raise SignalDriverErr([
(SignalDriverErrType.MULTIPLE_COMB_DRIVERS, self),
])
return self.drivers[0]
def markVisibilityOfSignalsAndCheckDrivers(netlist: "RtlNetlist"):
"""
* check if all signals are driven by something
* mark signals with hidden = False if they are connecting statements
or if they are external interface
"""
signals = netlist.signals
interfaceSignals = netlist.interfaces
signals_with_driver_issue = []
for sig in signals:
#if isinstance(sig._nop_val, (RtlSignal, InterfaceBase)):
# sig._nop_val.hidden = False
driver_cnt = len(sig.drivers)
has_comb_driver = False
if driver_cnt > 1:
sig.hidden = False
for d in sig.drivers:
if not isinstance(d, Operator):
sig.hidden = False
is_comb_driver = False
if isinstance(d, HdlPortItem):
is_comb_driver = True
elif d._event_dependent_from_branch is None:
for a in walk_assignments(d, sig):
if not a.indexes\
and a._event_dependent_from_branch != 0:
is_comb_driver = True
break
if has_comb_driver and is_comb_driver:
signals_with_driver_issue.append(
(SignalDriverErrType.MULTIPLE_COMB_DRIVERS, sig))
has_comb_driver |= is_comb_driver
elif driver_cnt == 1:
if not isinstance(sig.drivers[0], Operator):
sig.hidden = False
else:
sig.hidden = False
if sig not in interfaceSignals.keys():
if not sig.def_val._is_full_valid():
signals_with_driver_issue.append(
(SignalDriverErrType.MISSING_DRIVER, sig))
sig._const = True
# chec interface direction if required
d = interfaceSignals.get(sig, None)
if d is None:
pass
elif d is DIRECTION.IN:
assert sig.drivers, sig
if len(sig.drivers) != 1:
signals_with_driver_issue.append(
(SignalDriverErrType.INPUT_WITH_DRIVER, sig))
elif d is DIRECTION.OUT:
if not sig.drivers:
signals_with_driver_issue.append(
(SignalDriverErrType.OUTPUT_WITHOUT_DRIVER, sig))
if signals_with_driver_issue:
raise SignalDriverErr(signals_with_driver_issue)