use tlib functions to identify ffs and latches

src/kyupy/circuit.py

@@ -347,9 +347,9 @@ class Circuit:
         stats['__line__'] = len(self.lines)
         for n in self.cells.values():
             stats[n.kind] += 1
-            if 'dff' in n.kind.lower(): stats['__dff__'] += 1
+            if tlib.is_dff(n.kind): stats['__dff__'] += 1
-            elif 'latch' in n.kind.lower(): stats['__latch__'] += 1
+            elif tlib.is_latch(n.kind): stats['__latch__'] += 1
-            elif 'put' not in n.kind.lower(): stats['__comb__'] += 1 # no input or output
+            elif 'put' not in n.kind.lower(): stats['__comb__'] += 1 # don't count input or output towards comb
         stats['__seq__'] = stats['__dff__'] + stats['__latch__']
         return dict(stats)
 
@@ -581,24 +581,23 @@ class Circuit:
                 if line is not None:
                     yield line
 
-    def reversed_topological_order(self):
+    def reversed_topological_order(self, tlib: 'TechLib'): # type: ignore
         """Generator function to iterate over all nodes in reversed topological order.
 
-        Nodes without output lines and nodes whose :py:attr:`Node.kind` contains the
+        Nodes without output lines and sequential nodes (flip-flops, latches) are yielded first.
-        substrings 'dff' or 'latch' are yielded first.
         """
         visit_count = [0] * len(self.nodes)
-        queue = deque(n for n in self.nodes if len(n.outs) == 0 or 'dff' in n.kind.lower() or 'latch' in n.kind.lower())
+        queue = deque(n for n in self.nodes if len(n.outs) == 0 or tlib.is_dff(n.kind) or tlib.is_latch(n.kind))
         while len(queue) > 0:
             n = queue.popleft()
             for line in n.ins:
                 pred = line.driver
                 visit_count[pred] += 1
-                if visit_count[pred] == len(pred.outs) and 'dff' not in pred.kind.lower() and 'latch' not in pred.kind.lower():
+                if visit_count[pred] == len(pred.outs) and not tlib.is_dff(pred.kind) and not tlib.is_latch(pred.kind):
                     queue.append(pred)
             yield n
 
-    def fanin(self, origin_nodes):
+    def fanin(self, origin_nodes, tlib: 'TechLib'): # type: ignore
         """Generator function to iterate over the fan-in cone of a given list of origin nodes.
 
         Nodes are yielded in reversed topological order.
@@ -606,11 +605,10 @@ class Circuit:
         marks = [False] * len(self.nodes)
         for n in origin_nodes:
             marks[n] = True
-        for n in self.reversed_topological_order():
+        for n in self.reversed_topological_order(tlib):
             if not marks[n]:
-                for line in n.outs:
+                for line in n.outs.without_nones():
-                    if line is not None:
+                    marks[n] |= marks[line.reader]
-                        marks[n] |= marks[line.reader]
             if marks[n]:
                 yield n