Not 100% sure the expected results are right.  They seem plausible,
but I didn't actually analyze that the rounding is correct.

Define functions that use the VOPs for integer-length of signed and
unsigned 32-bit integers.

Test a few "interesting" integers with these functions.

This test was previously disabled only for Linux when running the CI.
However, it's now also failing when running the CI for Darwin.  Thus
disable it whenever we're running the CI.

I just manually tested this on my Linux and Mac boxes.  This test
passes without any problem.  Not sure what's going on.