intimg
         C: 0.29 s
      pypy: 0.99 s
pypy-trunk: 1.33 s
   cpython: 68.20 s

sum
         C: 0.61 s
      pypy: 0.59 s
pypy-trunk: 0.74 s
   cpython: 24.77 s

circular
         C: 0.47 s
      pypy: 1.48 s
pypy-trunk: 21.13 s
   cpython: 869.56 s

