experiments2/test_partsig.py

   1 #!/usr/bin/env python3
   2 # SPDX-License-Identifier: LGPL-2.1-or-later
   3 # See Notices.txt for copyright information
   4
   5 from nmigen import Signal, Module, Elaboratable
   6 from nmigen.back.pysim import Simulator, Delay
   7 from nmigen.cli import rtlil
   8
   9 from ieee754.part.partsig import PartitionedSignal
  10 from ieee754.part_mux.part_mux import PMux
  11
  12
  13 # XXX this is for coriolis2 experimentation
  14 class TestAddMod2(Elaboratable):
  15     def __init__(self, width, partpoints):
  16         self.partpoints = partpoints
  17         self.a = PartitionedSignal(partpoints, width)
  18         self.b = PartitionedSignal(partpoints, width)
  19         self.bsig = Signal(width)
  20         self.add_output = Signal(width)
  21         self.ls_output = Signal(width) # left shift
  22         self.ls_scal_output = Signal(width) # left shift
  23         self.sub_output = Signal(width)
  24         self.eq_output = Signal(len(partpoints)+1)
  25         self.gt_output = Signal(len(partpoints)+1)
  26         self.ge_output = Signal(len(partpoints)+1)
  27         self.ne_output = Signal(len(partpoints)+1)
  28         self.lt_output = Signal(len(partpoints)+1)
  29         self.le_output = Signal(len(partpoints)+1)
  30         self.mux_sel = Signal(len(partpoints)+1)
  31         self.mux_out = Signal(width)
  32         self.carry_in = Signal(len(partpoints)+1)
  33         self.add_carry_out = Signal(len(partpoints)+1)
  34         self.sub_carry_out = Signal(len(partpoints)+1)
  35         self.neg_output = Signal(width)
  36
  37     def elaborate(self, platform):
  38         m = Module()
  39         comb = m.d.comb
  40         sync = m.d.sync
  41         self.a.set_module(m)
  42         self.b.set_module(m)
  43         # compares
  44         sync += self.lt_output.eq(self.a < self.b)
  45         sync += self.ne_output.eq(self.a != self.b)
  46         sync += self.le_output.eq(self.a <= self.b)
  47         sync += self.gt_output.eq(self.a > self.b)
  48         sync += self.eq_output.eq(self.a == self.b)
  49         sync += self.ge_output.eq(self.a >= self.b)
  50         # add
  51         add_out, add_carry = self.a.add_op(self.a, self.b,
  52                                            self.carry_in)
  53         sync += self.add_output.eq(add_out)
  54         sync += self.add_carry_out.eq(add_carry)
  55         # sub
  56         sub_out, sub_carry = self.a.sub_op(self.a, self.b,
  57                                            self.carry_in)
  58         sync += self.sub_output.eq(sub_out)
  59         sync += self.sub_carry_out.eq(sub_carry)
  60         # neg
  61         sync += self.neg_output.eq(-self.a)
  62         # left shift
  63         sync += self.ls_output.eq(self.a << self.b)
  64         ppts = self.partpoints
  65         sync += self.mux_out.eq(PMux(m, ppts, self.mux_sel, self.a, self.b))
  66         # scalar left shift
  67         comb += self.bsig.eq(self.b.sig)
  68         sync += self.ls_scal_output.eq(self.a << self.bsig)
  69
  70         return m
  71
  72