Integrate Split and Concat Operators

src/finn/custom_op/fpgadataflow/__init__.py

@@ -42,6 +42,7 @@
 from finn.custom_op.fpgadataflow.lookup import Lookup
 from finn.custom_op.fpgadataflow.matrixvectoractivation import MVAU
 from finn.custom_op.fpgadataflow.pool import Pool
+from finn.custom_op.fpgadataflow.split import StreamingSplit
 from finn.custom_op.fpgadataflow.streamingdataflowpartition import (
     StreamingDataflowPartition,
 )
@@ -77,6 +78,7 @@
 custom_op["Lookup"] = Lookup
 custom_op["Pool"] = Pool
 custom_op["StreamingConcat"] = StreamingConcat
+custom_op["StreamingSplit"] = StreamingSplit
 custom_op["StreamingDataWidthConverter"] = StreamingDataWidthConverter
 custom_op["StreamingEltwise"] = StreamingEltwise
 custom_op["StreamingMaxPool"] = StreamingMaxPool

src/finn/custom_op/fpgadataflow/concat.py

@@ -27,7 +27,9 @@
 # OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
+import math
 import numpy as np
+import warnings
 from qonnx.core.datatype import DataType
 from qonnx.util.basic import roundup_to_integer_multiple
 
@@ -36,17 +38,18 @@
 
 class StreamingConcat(HWCustomOp):
     """Abstraction layer for HW implementation of Concat.
-    Only supports concatenating along the last axis."""
+    Only supports concatenating along the last (channel) axis."""
 
     def __init__(self, onnx_node, **kwargs):
         super().__init__(onnx_node, **kwargs)
 
     def get_nodeattr_types(self):
         my_attrs = {
+            "SIMD": ("i", True, 0),
             # number of elements from each stream to concat
-            "ElemsPerStream": ("ints", True, []),
-            # FINN DataTypes for inputs; output datatype inferred from input
-            "inputDataType": ("s", True, ""),
+            "ChannelsPerStream": ("ints", True, []),
+            # FINN DataTypes for inputs; output datatype inferred from inputs
+            "inputDataTypes": ("strings", True, [""]),
             # number of input vectors for non-concat axes, examples:
             # [1] is a single vector (like a FC layer with batch=1)
             # [4] is four vectors (like a FC layer with batch=4)
@@ -57,29 +60,36 @@ def get_nodeattr_types(self):
         return my_attrs
 
     def get_n_inputs(self):
-        return len(self.get_nodeattr("ElemsPerStream"))
+        return len(self.get_nodeattr("ChannelsPerStream"))
 
     def get_total_elems(self):
-        elems_per_stream = self.get_nodeattr("ElemsPerStream")
+        elems_per_stream = self.get_nodeattr("ChannelsPerStream")
         return int(np.sum(elems_per_stream))
 
     def get_normal_input_shape(self, ind=0):
-        elems_per_stream = self.get_nodeattr("ElemsPerStream")
+        elems_per_stream = self.get_nodeattr("ChannelsPerStream")
         elems = elems_per_stream[ind]
         vecs = list(self.get_nodeattr("numInputVectors"))
         ishape = tuple(vecs + [elems])
         return ishape
 
     def get_folded_input_shape(self, ind=0):
-        return self.get_normal_input_shape(ind)
+        simd = self.get_nodeattr("SIMD")
+        folds = self.get_nodeattr("ChannelsPerStream")[ind] // simd
+        vecs = list(self.get_nodeattr("numInputVectors"))
+        return tuple(vecs + [folds, simd])
 
     def get_normal_output_shape(self, ind=0):
         total_elems = self.get_total_elems()
         vecs = list(self.get_nodeattr("numInputVectors"))
         return tuple(vecs + [total_elems])
 
     def get_folded_output_shape(self, ind=0):
-        return self.get_normal_output_shape()
+        total_elems = self.get_total_elems()
+        simd = self.get_nodeattr("SIMD")
+        folds = total_elems // simd
+        vecs = list(self.get_nodeattr("numInputVectors"))
+        return tuple(vecs + [folds, simd])
 
     def make_shape_compatible_op(self, model):
         # check all input shapes
@@ -94,7 +104,16 @@ def infer_node_datatype(self, model):
         # check all input datatypes
         for i, inp in enumerate(self.onnx_node.input):
             idt = model.get_tensor_datatype(inp)
-            assert idt == self.get_input_datatype()
+            if idt != self.get_input_datatype(i):
+                warn_str = "inputDataType changing for %s: %s -> %s " % (
+                    self.onnx_node.name,
+                    str(self.get_input_datatype(i)),
+                    str(idt),
+                )
+                warnings.warn(warn_str)
+                old_datatypes_attr = self.get_nodeattr("inputDataTypes")
+                old_datatypes_attr[i] = idt.name
+                self.set_nodeattr("inputDataTypes", old_datatypes_attr)
         odt = self.get_output_datatype()
         model.set_tensor_datatype(self.onnx_node.output[0], odt)
 
@@ -103,21 +122,37 @@ def verify_node(self):
 
     def get_input_datatype(self, ind=0):
         # input dt identical for all inputs
-        return DataType[self.get_nodeattr("inputDataType")]
+        return DataType[self.get_nodeattr("inputDataTypes")[ind]]
 
     def get_output_datatype(self, ind=0):
-        return self.get_input_datatype()
+        # infer output datatype from declared inputDataTypes
+        min_input = 0
+        max_input = 0
+        for i in range(len(self.get_nodeattr("inputDataTypes"))):
+            idt = self.get_input_datatype(i)
+            if idt.min() < min_input:
+                min_input = idt.min()
+            if idt.max() > max_input:
+                max_input = idt.max()
+        # if the input range is always greater than 0, then acc_max <= 2^P - 1
+        if min_input >= 0:
+            out_bit_width = math.ceil(np.log2(max_input + 1))
+            odt = DataType[f"UINT{out_bit_width}"]
+        # if the input range is signed, then acc_min >= -2^{P-1} and acc_max <=
+        # 2^{P - 1} - 1, which means 2^{P - 1} >= max(-acc_min, 1 + acc_max)
+        else:
+            max_abs_input = max(-min_input, 1 + max_input)
+            out_bit_width = math.ceil(np.log2(max_abs_input) + 1)
+            odt = DataType[f"INT{out_bit_width}"]
+        return odt
 
     def get_instream_width(self, ind=0):
-        elems_per_stream = self.get_nodeattr("ElemsPerStream")
-        elems = elems_per_stream[ind]
-        ibits = self.get_input_datatype().bitwidth()
-        return elems * ibits
+        ibits = self.get_input_datatype(ind).bitwidth()
+        return ibits * self.get_nodeattr("SIMD")
 
     def get_outstream_width(self, ind=0):
         obits = self.get_output_datatype().bitwidth()
-        total_elems = self.get_total_elems()
-        out_width = total_elems * obits
+        out_width = obits * self.get_nodeattr("SIMD")
         return out_width
 
     def get_number_output_values(self):

src/finn/custom_op/fpgadataflow/hls/__init__.py

@@ -43,6 +43,7 @@
 from finn.custom_op.fpgadataflow.hls.lookup_hls import Lookup_hls
 from finn.custom_op.fpgadataflow.hls.matrixvectoractivation_hls import MVAU_hls
 from finn.custom_op.fpgadataflow.hls.pool_hls import Pool_hls
+from finn.custom_op.fpgadataflow.hls.split_hls import StreamingSplit_hls
 from finn.custom_op.fpgadataflow.hls.streamingdatawidthconverter_hls import (
     StreamingDataWidthConverter_hls,
 )
@@ -71,6 +72,7 @@
 custom_op["Lookup_hls"] = Lookup_hls
 custom_op["Pool_hls"] = Pool_hls
 custom_op["StreamingConcat_hls"] = StreamingConcat_hls
+custom_op["StreamingSplit_hls"] = StreamingSplit_hls
 custom_op["StreamingEltwise_hls"] = StreamingEltwise_hls
 custom_op["StreamingDataWidthConverter_hls"] = StreamingDataWidthConverter_hls
 custom_op["StreamingMaxPool_hls"] = StreamingMaxPool_hls