Change input_indexes_required_for_output_port to be iterative and use bfs

b_asic/signal_flow_graph.py

@@ -254,7 +254,30 @@ class SFG(AbstractOperation):
         if output_index < 0 or output_index >= self.output_count:
             raise IndexError(
                 f"Output index out of range (expected 0-{self.output_count - 1}, got {output_index})")
-        return self._inputs_required_for_source(self._output_operations[output_index].input(0).signals[0].source, set())
+
+        input_indexes_required = []
+        sfg_input_operations_to_indexes = {
+            input_op: index for index, input_op in enumerate(self._input_operations)}
+        output_op = self._output_operations[output_index]
+        queue = deque([output_op])
+        visited = set([output_op])
+        while queue:
+            op = queue.popleft()
+            if isinstance(op, Input):
+                if op in sfg_input_operations_to_indexes:
+                    input_indexes_required.append(
+                        sfg_input_operations_to_indexes[op])
+                    del sfg_input_operations_to_indexes[op]
+
+            for input_port in op.inputs:
+                for signal in input_port.signals:
+                    if signal.source is not None:
+                        new_op = signal.source.operation
+                        if new_op not in visited:
+                            queue.append(new_op)
+                            visited.add(new_op)
+
+        return input_indexes_required
 
     def copy_component(self, *args, **kwargs) -> GraphComponent:
         return super().copy_component(*args, **kwargs, inputs=self._input_operations, outputs=self._output_operations,
@@ -526,19 +549,3 @@ class SFG(AbstractOperation):
         print(self._precedence_list)
 
         return self._precedence_list
-
-    def _inputs_required_for_source(self, src: OutputPort, visited: MutableSet[Operation]) -> Sequence[bool]:
-        if src.operation in visited:
-            return []
-        visited.add(src.operation)
-
-        if isinstance(src.operation, Input):
-            for i, input_operation in enumerate(self._input_operations):
-                if input_operation is src.operation:
-                    return [i]
-
-        input_indices = []
-        for i in src.operation.inputs_required_for_output(src.index):
-            input_indices.extend(self._inputs_required_for_source(
-                src.operation.input(i).signals[0].source, visited))
-        return input_indices