5 ms·

Duh, you're right on both counts. It should work for any odd divisor, I was just computing the inverse in a dumb way when I tried out other divisors. And I shou

Duh, you're right on both counts. It should work for any odd divisor, I was just computing the inverse in a dumb way when I tried out other divisors. And I should have stated u32 wrapping arithmetic.

im3w1l 10y ago
And for even divisors you can separate the divisor into a power of two, and an odd part. The odd part is checked as before, and the power of two is checked with an and mask.
- raphlinus 10y ago
  An even trickier way to do this is to rotate right by the power of two factor between doing the multiply and the compare.
  - im3w1l 10y ago
    That wouldn't work, because a number that is bigger than the threshold could become smaller than it after the rotation.