src/ieee754/part/partsig.py

   1 # SPDX-License-Identifier: LGPL-2.1-or-later
   2 # See Notices.txt for copyright information
   3
   4 """
   5 Copyright (C) 2020 Luke Kenneth Casson Leighton <lkcl@lkcl.net>
   6
   7 dynamic-partitionable class similar to Signal, which, when the partition
   8 is fully open will be identical to Signal.  when partitions are closed,
   9 the class turns into a SIMD variant of Signal.  *this is dynamic*.
  10
  11 http://bugs.libre-riscv.org/show_bug.cgi?id=132
  12 """
  13
  14 from ieee754.part_mul_add.adder import PartitionedAdder
  15 from nmigen import (Signal,
  16                     )
  17
  18 class PartitionedSignal:
  19     def __init__(self, partition_points, *args, **kwargs):
  20         self.partpoints = partition_points
  21         self.sig = Signal(*args, **kwargs)
  22         self.modnames = {}
  23         for name in ['add']:
  24             self.modnames[name] = 0
  25
  26     def set_module(self, m):
  27         self.m = m
  28
  29     def get_modname(self, category):
  30         self.modnames[category] += 1
  31         return "%s%d" % (category, self.modnames[category])
  32
  33     def eq(self, val):
  34         return self.sig.eq(val)
  35
  36     def __xor__(self, other):
  37         if isinstance(other, PartitionedSignal):
  38             return self.sig ^ other.sig
  39         return self.sig ^ other
  40
  41     def __add__(self, other):
  42         shape = self.sig.shape()
  43         pa = PartitionedAdder(shape[0], self.partpoints)
  44         setattr(self.m.submodules, self.get_modname('add'), pa)
  45         comb = self.m.d.comb
  46         comb += pa.a.eq(self.sig)
  47         if isinstance(other, PartitionedSignal):
  48             comb += pa.b.eq(other.sig)
  49         else:
  50             comb += pa.b.eq(other)
  51         return pa.output