utils/analysis/objdiff.py

   1 #!/usr/bin/python
   2 import sys
   3 from subprocess import Popen, PIPE
   4
   5 if len(sys.argv) != 3:
   6     print """%s usage:
   7     %s obj1 obj2
   8     Calculate per-symbol and total size differences between obj1 and obj2,
   9     which may be any files that nm can read""" % ((sys.argv[0],)*2)
  10     sys.exit(2)
  11
  12 obj1 = sys.argv[1]
  13 obj2 = sys.argv[2]
  14
  15 def getsyms(obj):
  16     proc = Popen(args=['nm', '-S', '-t', 'd', obj], stdout=PIPE, stderr=PIPE)
  17     out, err = proc.communicate()
  18     if err:
  19         print "nm reported an error:\n"
  20         print err
  21         sys.exit(1)
  22     d = {}
  23     for l in out.splitlines():
  24         l = l.strip().split()
  25         if len(l) == 4:
  26             d[l[3]] = int(l[1])
  27     return d
  28
  29 diff = 0
  30
  31 d1 = getsyms(obj1)
  32 d2 = getsyms(obj2)
  33 l = [(k,v) for k,v in sorted(d1.items()) if k not in d2]
  34 if l:
  35     print "only in %s" % obj1
  36     print ''.join("  %6d %s\n" % (v,k) for k,v in l)
  37     diff -= sum(v for k,v in l)
  38
  39 l = [(k,v) for k,v in sorted(d2.items()) if k not in d1]
  40 if l:
  41     print "only in %s" % obj2
  42     print ''.join("%6d %s\n" % (v,k) for k,v in l)
  43     diff += sum(v for k,v in l)
  44
  45 l = [(k,v,d2[k]) for k,v in sorted(d1.items()) if k in d2 and d2[k] != v]
  46 if l:
  47     print "different sizes in %s and %s:" %(obj1, obj2)
  48     print ''.join("  %6d %6d %s\n" % (v1,v2,k) for k,v1,v2 in l)
  49     diff += sum(v2-v1 for k,v1,v2 in l)
  50
  51 if diff:
  52     print "total size difference: %+d" % diff
  53 else:
  54     print "total size difference:  0"