My method, first builds an approximation of the solution of
a/b as...
s1 = ((a / 2) / b) * 2;
a / 2 is done using the bug-free shift-right operator (
>>) and results always in a number with bit 64 unset, so we can divide it by
b without incurring in the convert-to-NV bug. Again multiplying by 2 is done with the shift-left operator (
<<).
Then, we use the approximation to build the exact solution as:
s = s1 + (a - s1 * b) / b
Well, actually, in order to do everything using bug-free operations, the code uses the following equivalence:
s2 = (a / 2) / b
s1 = s2 * 2
s = s1 + (a - s1 * b) / b
s = s2 * 2 + (a - (s2 * b) * 2) / b
where
$d is
s2, and
$e is
(a - (s2 * b) * 2).