mdw@git.distorted.org.uk Git - mLib/blob - utils/t/bits-testgen.py

   1 #! /usr/bin/python
   2 ### -*-python-*-
   3 ###
   4 ### Generate input script and expected output for bit manipulation,
   5 ### particularly 64-bit arithmetic.
   6
   7 import sys as SYS
   8 import random as R
   9
  10 if SYS.version_info >= (3,): xrange = range
  11
  12 NVEC = 64
  13 WD = 64
  14 LIMIT = 1 << WD
  15 MASK = LIMIT - 1
  16
  17 ARGS = SYS.argv[1:]; ARGS.reverse()
  18 def arg(default = None):
  19   if len(ARGS): return ARGS.pop()
  20   else: return default
  21
  22 R.seed(None)
  23 seed = arg()
  24 if seed is None: SEED = R.randrange(0, 1 << 32)
  25 else: SEED = int(seed, 0)
  26 R.seed(SEED)
  27
  28 print('### Test vectors for 64-bit arithmetic macros')
  29 print('###   [generated; seed = 0x%08x]' % SEED)
  30
  31 def rol(x, n): return ((x << n) | (x >> (WD - n))) & MASK
  32 def ror(x, n): return ((x >> n) | (x << (WD - n))) & MASK
  33 def put(x): return '%0*x' % (WD//4, x)
  34
  35 for name, func in [('lsl', lambda x, n: x << n),
  36                    ('lsr', lambda x, n: x >> n),
  37                    ('rol', rol),
  38                    ('ror', ror)]:
  39   print('\n%s64 {' % name)
  40   for i in xrange(NVEC):
  41     x = R.randrange(LIMIT)
  42     sh = R.randrange(0, 70) & 63
  43     print('  %s %2d %s;' % (put(x), sh, put(func(x, sh) & MASK)))
  44   for i in xrange(4):
  45     x = R.randrange(LIMIT)
  46     sh = 32
  47     print('  %s %2d %s;' % (put(x), sh, put(func(x, sh) & MASK)))
  48   print('}')
  49
  50 for name, func in [('add', lambda x, y: x + y),
  51                    ('sub', lambda x, y: x - y)]:
  52   print('\n%s64 {' % name)
  53   for i in xrange(NVEC):
  54     x = R.randrange(LIMIT)
  55     y = R.randrange(LIMIT)
  56     print('  %s %s %s;' % (put(x), put(y), put(func(x, y) & MASK)))
  57   print('}')