From 436f4332ebfed0e4b9fdd1dbd5781d9cf41689e6 Mon Sep 17 00:00:00 2001
From: Luke Kenneth Casson Leighton <lkcl@lkcl.net>
Date: Fri, 23 Aug 2019 11:36:37 +0100
Subject: [PATCH] split out AddReduce module level creation

---
 src/ieee754/part_mul_add/multiply.py | 65 +++++++++++++++++++++++++---
 1 file changed, 58 insertions(+), 7 deletions(-)

diff --git a/src/ieee754/part_mul_add/multiply.py b/src/ieee754/part_mul_add/multiply.py
index e0531b42..95fa45a6 100644
--- a/src/ieee754/part_mul_add/multiply.py
+++ b/src/ieee754/part_mul_add/multiply.py
@@ -515,7 +515,7 @@ class AddReduceSingle(Elaboratable):
         return m
 
 
-class AddReduce(Elaboratable):
+class AddReduceInternal:
     """Recursively Add list of numbers together.
 
     :attribute inputs: input ``Signal``s to be summed. Modification not
@@ -527,26 +527,77 @@ class AddReduce(Elaboratable):
         supported, except for by ``Signal.eq``.
     """
 
-    def __init__(self, inputs, output_width, register_levels, partition_points,
+    def __init__(self, inputs, output_width, partition_points,
                        part_ops):
         """Create an ``AddReduce``.
 
         :param inputs: input ``Signal``s to be summed.
         :param output_width: bit-width of ``output``.
-        :param register_levels: List of nesting levels that should have
-            pipeline registers.
         :param partition_points: the input partition points.
         """
         self.inputs = inputs
         self.part_ops = part_ops
-        n_parts = len(part_ops)
-        self.o = FinalReduceData(partition_points, output_width, n_parts)
         self.output_width = output_width
-        self.register_levels = register_levels
         self.partition_points = partition_points
 
         self.create_levels()
 
+    def create_levels(self):
+        """creates reduction levels"""
+
+        mods = []
+        partition_points = self.partition_points
+        part_ops = self.part_ops
+        n_parts = len(part_ops)
+        inputs = self.inputs
+        ilen = len(inputs)
+        while True:
+            groups = AddReduceSingle.full_adder_groups(len(inputs))
+            if len(groups) == 0:
+                break
+            next_level = AddReduceSingle(ilen, self.output_width, n_parts,
+                                         partition_points)
+            mods.append(next_level)
+            partition_points = next_level.i.part_pts
+            inputs = next_level.o.terms
+            ilen = len(inputs)
+            part_ops = next_level.i.part_ops
+
+        next_level = FinalAdd(ilen, self.output_width, n_parts,
+                              partition_points)
+        mods.append(next_level)
+
+        self.levels = mods
+
+
+class AddReduce(AddReduceInternal, Elaboratable):
+    """Recursively Add list of numbers together.
+
+    :attribute inputs: input ``Signal``s to be summed. Modification not
+        supported, except for by ``Signal.eq``.
+    :attribute register_levels: List of nesting levels that should have
+        pipeline registers.
+    :attribute output: output sum.
+    :attribute partition_points: the input partition points. Modification not
+        supported, except for by ``Signal.eq``.
+    """
+
+    def __init__(self, inputs, output_width, register_levels, partition_points,
+                       part_ops):
+        """Create an ``AddReduce``.
+
+        :param inputs: input ``Signal``s to be summed.
+        :param output_width: bit-width of ``output``.
+        :param register_levels: List of nesting levels that should have
+            pipeline registers.
+        :param partition_points: the input partition points.
+        """
+        AddReduceInternal.__init__(self, inputs, output_width,
+                                   partition_points, part_ops)
+        n_parts = len(part_ops)
+        self.o = FinalReduceData(partition_points, output_width, n_parts)
+        self.register_levels = register_levels
+
     @staticmethod
     def get_max_level(input_count):
         return AddReduceSingle.get_max_level(input_count)
-- 
2.30.2