Compute base-2 log of
This is internally implemented as count-leading-zeros machine instruction.
Calculate the integer base 2 logarithm of an
calculation is more efficient than for the general case, on
platforms with 32- or 64-bit words much more efficient.
The argument must be strictly positive, that condition is not checked.
Calculate the integer logarithm for an arbitrary base.
The base must be greater than
1, the second argument, the number
whose logarithm is sought, shall be positive, otherwise the
result is meaningless.
The following property holds
integerLogBase#base m <= m < base ^(
integerLogBase#base m + 1)
base > 1 and
m > 0.
Note: Internally uses
integerLog2# for base 2