Reuse bias tensor when extracting the bias from Conv nodes.

src/finn/transformation/qonnx/extract_conv_bias.py

@@ -59,17 +59,12 @@ class ExtractBiasFromConv(Transformation):
 
                     # Insert bias as Add node behind the Conv node
                     out_shape = model.get_tensor_shape(n.output[0])
+                    # Reshape bias tensor
                     add_shape = [1] * len(out_shape)
                     # ToDo: this must change to "add_shape[-1] = bias.shape[0]" when
                     #  channels last comes around
                     add_shape[1] = bias.shape[0]
-                    add_tensor = helper.make_tensor_value_info(
-                        model.make_new_valueinfo_name(),
-                        TensorProto.FLOAT,
-                        add_shape,
-                    )
-                    graph.value_info.append(add_tensor)
-                    model.set_initializer(add_tensor.name, bias.reshape(add_shape))
+                    model.set_initializer(n.input[2], bias.reshape(add_shape))
 
                     act_add_tensor = helper.make_tensor_value_info(
                         model.make_new_valueinfo_name(),
@@ -80,7 +75,7 @@ class ExtractBiasFromConv(Transformation):
 
                     add_node = helper.make_node(
                         "Add",
-                        [act_add_tensor.name, add_tensor.name],
+                        [act_add_tensor.name, n.input[2]],
                         [n.output[0]],
                     )
                     graph.node.insert(node_ind, add_node)