src/openpower/decoder/isa/maxloc.py

   1 # Implementation of FORTRAN maxloc in python
   2 # Copyright (C) Luke Kenneth Casson Leighton <lkcl@lkcl.net>
   3 # License: LGPLv3+
   4 # https://bugs.libre-soc.org/show_bug.cgi?id=676#c2
   5
   6 from random import randint
   7
   8 def m2(a):
   9     m = 0;
  10     nm = 0;
  11     i = 0;
  12     n = len(a)
  13
  14     while (i<n):
  15         while (i<n and a[i]<=m) :
  16             print("%d idx %d <= m %d" % ( i, a[i], m))
  17             i += 1
  18         while  (i < n and a[i] > m) :
  19             print("%d idx %d > m %d" % (i, a[i], m))
  20             m = a[i]
  21             nm = i
  22             i += 1
  23     return nm;
  24
  25 def sv_maxu(gpr, CR, vl, ra, rb, rt):
  26     i = 0
  27     while i < vl:
  28         CR[0] = cmpd(gpr[ra+i], gpr[rb])
  29         log("sv_maxss test", i, gpr[ra + i], gpr[rb], CR[0], int(CR[0]))
  30         gpr[rt] = gpr[ra+i] if CR[0].lt else gpr[rb]
  31         if not CR[0].gt:
  32             break
  33         i += 1
  34     return i # new VL
  35
  36 # this version is more akin to SVP64, using an implementation of sv.minmax
  37 def m3(a):
  38     m = 0;
  39     nm = 0;
  40     i = 0;
  41     n = len(a)
  42     vl = 4
  43
  44     while (i<n):
  45         while (i<n and a[i]<=m) :
  46             print("%d idx %d <= m %d" % ( i, a[i], m))
  47             i += 1
  48         while  (i < n and a[i] > m) :
  49             print("%d idx %d > m %d" % (i, a[i], m))
  50             m = a[i]
  51             nm = i
  52             i += 1
  53     return nm;
  54
  55 # /*Testbench*/
  56
  57 test_data = [
  58     ([5,2,8,1,3,7,9,4], 6),
  59     ([5,2,8,9,9,7,9,4], 3),
  60     ([0,0,0,0,0,0,0,0], 0),
  61     ([5,5,5,5,5,5,5,5], 0),
  62 ]
  63
  64 if __name__ == '__main__':
  65     for arr, expected in test_data:
  66         print("search list", arr)
  67         result = m2(arr)
  68         print("Index of the maximum value in an array is: %d" % result)
  69         assert (result == expected)
  70
  71     # test m2 against m3
  72     for i in range(200):
  73         array_len = randint(2, 15)
  74         array = []
  75         for j in range(array_len):
  76             array.append(randint(0, 20))
  77         print("randomised search list", array)
  78         expected = m2(array)
  79         print("Index of the maximum value in an array is: %d" % expected)
  80         assert (m3(array) == expected)