src/ieee754/add/test_multishift.py

   1 from random import randint
   2 from nmigen import Module, Signal
   3 from nmigen.compat.sim import run_simulation
   4
   5 from fpbase import MultiShift, MultiShiftR, MultiShiftRMerge
   6
   7 class MultiShiftModL:
   8     def __init__(self, width):
   9         self.ms = MultiShift(width)
  10         self.a = Signal(width)
  11         self.b = Signal(self.ms.smax)
  12         self.x = Signal(width)
  13
  14     def elaborate(self, platform=None):
  15
  16         m = Module()
  17         m.d.comb += self.x.eq(self.ms.lshift(self.a, self.b))
  18
  19         return m
  20
  21 class MultiShiftModR:
  22     def __init__(self, width):
  23         self.ms = MultiShift(width)
  24         self.a = Signal(width)
  25         self.b = Signal(self.ms.smax)
  26         self.x = Signal(width)
  27
  28     def elaborate(self, platform=None):
  29
  30         m = Module()
  31         m.d.comb += self.x.eq(self.ms.rshift(self.a, self.b))
  32
  33         return m
  34
  35 class MultiShiftModRMod:
  36     def __init__(self, width):
  37         self.ms = MultiShiftR(width)
  38         self.a = Signal(width)
  39         self.b = Signal(self.ms.smax)
  40         self.x = Signal(width)
  41
  42     def elaborate(self, platform=None):
  43
  44         m = Module()
  45         m.submodules += self.ms
  46         m.d.comb += self.ms.i.eq(self.a)
  47         m.d.comb += self.ms.s.eq(self.b)
  48         m.d.comb += self.x.eq(self.ms.o)
  49
  50         return m
  51
  52 class MultiShiftRMergeMod:
  53     def __init__(self, width):
  54         self.ms = MultiShiftRMerge(width)
  55         self.a = Signal(width)
  56         self.b = Signal(self.ms.smax)
  57         self.x = Signal(width)
  58
  59     def elaborate(self, platform=None):
  60
  61         m = Module()
  62         m.submodules += self.ms
  63         m.d.comb += self.ms.inp.eq(self.a)
  64         m.d.comb += self.ms.diff.eq(self.b)
  65         m.d.comb += self.x.eq(self.ms.m)
  66
  67         return m
  68
  69
  70 def check_case(dut, width, a, b):
  71     yield dut.a.eq(a)
  72     yield dut.b.eq(b)
  73     yield
  74
  75     x = (a << b) & ((1<<width)-1)
  76
  77     out_x = yield dut.x
  78     assert out_x == x, "Output x 0x%x not equal to expected 0x%x" % (out_x, x)
  79
  80 def check_caser(dut, width, a, b):
  81     yield dut.a.eq(a)
  82     yield dut.b.eq(b)
  83     yield
  84
  85     x = (a >> b) & ((1<<width)-1)
  86
  87     out_x = yield dut.x
  88     assert out_x == x, "Output x 0x%x not equal to expected 0x%x" % (out_x, x)
  89
  90
  91 def check_case_merge(dut, width, a, b):
  92     yield dut.a.eq(a)
  93     yield dut.b.eq(b)
  94     yield
  95
  96     x = (a >> b) & ((1<<width)-1) # actual shift
  97     if (a & ((2<<b)-1)) != 0: # mask for sticky bit
  98         x |= 1 # set LSB
  99
 100     out_x = yield dut.x
 101     assert out_x == x, \
 102                 "\nshift %d\nInput\n%+32s\nOutput x\n%+32s != \n%+32s" % \
 103                         (b, bin(a), bin(out_x), bin(x))
 104
 105 def testmerge(dut):
 106     for i in range(32):
 107         for j in range(1000):
 108             a = randint(0, (1<<32)-1)
 109             yield from check_case_merge(dut, 32, a, i)
 110
 111 def testbench(dut):
 112     for i in range(32):
 113         for j in range(1000):
 114             a = randint(0, (1<<32)-1)
 115             yield from check_case(dut, 32, a, i)
 116
 117 def testbenchr(dut):
 118     for i in range(32):
 119         for j in range(1000):
 120             a = randint(0, (1<<32)-1)
 121             yield from check_caser(dut, 32, a, i)
 122
 123 if __name__ == '__main__':
 124     dut = MultiShiftRMergeMod(width=32)
 125     run_simulation(dut, testmerge(dut), vcd_name="test_multishiftmerge.vcd")
 126     dut = MultiShiftModRMod(width=32)
 127     run_simulation(dut, testbenchr(dut), vcd_name="test_multishift.vcd")
 128
 129     dut = MultiShiftModR(width=32)
 130     run_simulation(dut, testbenchr(dut), vcd_name="test_multishift.vcd")
 131
 132     dut = MultiShiftModL(width=32)
 133     run_simulation(dut, testbench(dut), vcd_name="test_multishift.vcd")
 134