[FIFO] Ignore (1,) dims when doing FIFO insertion

src/finn/transformation/fpgadataflow/insert_fifo.py

@@ -4,6 +4,7 @@ from onnx import helper as oh
 from finn.custom_op.registry import getCustomOp
 from finn.transformation import Transformation
 from finn.util.fpgadataflow import is_fpgadataflow_node
+import numpy as np
 
 
 def _is_fifo_node(node):
@@ -26,6 +27,14 @@ def _suitable_node(node):
         return False
 
 
+def _suitable_folded_shapes(ishape, oshape):
+    i_dummy = np.random.rand(*ishape)
+    o_dummy = np.random.rand(*oshape)
+    ishape_canonical = np.squeeze(i_dummy).shape
+    oshape_canonical = np.squeeze(o_dummy).shape
+    return ishape_canonical == oshape_canonical
+
+
 class InsertFIFO(Transformation):
     """Inserting FIFOs in the beginning and end of the graph as well as
     between fpgadataflow nodes.
@@ -59,8 +68,9 @@ class InsertFIFO(Transformation):
                     # check if folded_shape of output of first node and
                     # input of the second node is equal
                     n1 = getCustomOp(consumer)
-                    assert (
-                        fld_shape == n1.get_folded_input_shape()
+                    fld_shape_2 = n1.get_folded_input_shape()
+                    assert _suitable_folded_shapes(
+                        fld_shape, fld_shape_2
                     ), """The
                     folded output shape of the first node is not the same as the
                     folded output shape of the second node. A streaming fifo can't