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