Set accum_t to input tensor precision if not set

Author: vloncar

hls4ml/model/hls_layers.py

@@ -360,9 +360,24 @@ def __init__(self, model, name, attributes, inputs, outputs=None):
         self.weights = OrderedDict()
         self.variables = OrderedDict()
         self.precision = OrderedDict()
-        accum_t = HLSType(*reversed(self.model.config.get_precision(self, 'accum')))
+
+        # We set 'accum' precision to match input tensor's precision if 'accum' was not explicitly set
+        def_type_obj, _ = self.model.config.get_precision(self, 'default')
+        acc_type_obj, acc_type_name = self.model.config.get_precision(self, 'accum')
+
+        inp = self.get_input_variable()
+        if inp is not None:
+            inp_type_obj = inp.type.precision
+        else:
+            inp_type_obj = def_type_obj
+
+        if acc_type_obj == def_type_obj: # 'accum' precision not defined in config
+            acc_type_obj = inp_type_obj # use input tensor's precision for 'accum'
+
+        accum_t = HLSType(acc_type_name, acc_type_obj) 
         self.precision[accum_t.name] = accum_t
         self.set_attr('accum_t', accum_t.precision)
+
         self.reuse_factor = self.model.config.get_reuse_factor(self)
 
         layer_config = self.model.config.get_layer_config(self)

hls4ml/model/hls_model.py

@@ -439,7 +439,7 @@ def get_output_variables(self):
         return variables
 
     def get_layer_output_variable(self, output_name):
-        return self.output_vars[output_name]
+        return self.output_vars.get(output_name, None)
 
     def write(self):
         def make_stamp():