Merge pull request #153 from project-rig/interposer-changes-rebased

Use interposers to reduce network traffic

nengo_spinnaker/builder/builder.py

@@ -206,6 +206,11 @@ def build(self, network, **kwargs):
         with self.decoder_cache:
             self._build_network(network)
 
+        # Insert interposers
+        interposers, connection_map = self.connection_map.insert_interposers()
+        self.extra_operators.extend(interposers)
+        self.connection_map = connection_map
+
     def _build_network(self, network):
         # Get the seed for the network
         self.seeds[network] = get_seed(network, np.random)
@@ -319,11 +324,6 @@ def make_netlist(self, *args, **kwargs):
             A netlist which can be placed and routed to simulate this model on
             a SpiNNaker machine.
         """
-        # Remove any passthrough Nodes which don't connect to anything
-        from nengo_spinnaker import operators
-        removed_operators = model.remove_sinkless_objects(self.connection_map,
-                                                          operators.Filter)
-
         # Call each operator to make vertices
         operator_vertices = dict()
         load_functions = collections_ext.noneignoringlist()
@@ -336,8 +336,8 @@ def make_netlist(self, *args, **kwargs):
 
         for op in itertools.chain(itervalues(self.object_operators),
                                   self.extra_operators):
-            # Skip any operators that were previously removed
-            if op in removed_operators:
+            # If the operator is a passthrough Node then skip it
+            if isinstance(op, model.PassthroughNode):
                 continue
 
             # Otherwise call upon the operator to build vertices for the

nengo_spinnaker/builder/connection.py

@@ -1,6 +1,7 @@
 import nengo
 from .builder import Model, ObjectPort, spec
-from .model import ReceptionParameters, InputPort, OutputPort
+from .model import ReceptionParameters
+from .ports import InputPort, OutputPort
 
 
 @Model.source_getters.register(nengo.base.NengoObject)

nengo_spinnaker/builder/ensemble.py

@@ -10,9 +10,10 @@
 import numpy as np
 
 from .builder import BuiltConnection, Model, ObjectPort, spec
-from .transmission_parameters import EnsembleTransmissionParameters
-from .model import InputPort, OutputPort
-from .ports import EnsembleInputPort, EnsembleOutputPort
+from .transmission_parameters import Transform, EnsembleTransmissionParameters
+from .ports import (
+    EnsembleInputPort, EnsembleOutputPort, InputPort, OutputPort
+)
 from .. import operators
 from ..utils import collections as collections_ext
 
@@ -39,11 +40,10 @@ def get_ensemble_source(model, conn):
 
 
 @Model.source_getters.register(nengo.ensemble.Neurons)
-def get_neurons_source(model, connection):
+def get_neurons_source(model, conn):
     """Get the source for connections out of neurons."""
-    raise NotImplementedError(
-        "SpiNNaker does not currently support neuron to neuron connections"
-    )
+    ens = model.object_operators[conn.pre_obj.ensemble]
+    return spec(ObjectPort(ens, EnsembleOutputPort.neurons))
 
 
 @Model.sink_getters.register(nengo.Ensemble)
@@ -241,19 +241,19 @@ def build_from_ensemble_connection(model, conn):
                                          transform=transform,
                                          solver_info=solver_info)
 
-    return EnsembleTransmissionParameters(decoders.T,
-                                          conn.post_obj.size_in,
-                                          conn.post_slice,
-                                          conn.learning_rule,
-                                          transform)
+    t = Transform(size_in=decoders.shape[1],
+                  size_out=conn.post_obj.size_in,
+                  transform=transform,
+                  slice_out=conn.post_slice)
+    return EnsembleTransmissionParameters(
+            decoders.T, t, conn.learning_rule
+    )
 
 
 @Model.transmission_parameter_builders.register(nengo.ensemble.Neurons)
 def build_from_neurons_connection(model, conn):
     """Build the parameters object for a connection from Neurons."""
-    raise NotImplementedError(
-        "SpiNNaker does not currently support connections from Neurons"""
-    )
+    return object()
 
 
 @Model.probe_builders.register(nengo.Ensemble)