Function advanceUntil

setutil.go:405–458

(
	array []uint16,
	pos int,
	length int,
	min uint16,
)

}

func advanceUntil(
	array []uint16,
	pos int,
	length int,
	min uint16,
) int {
	lower := pos + 1

	if lower >= length || array[lower] >= min {
		return lower
	}

	spansize := 1

	for lower+spansize < length && array[lower+spansize] < min {
		spansize *= 2
	}
	var upper int
	if lower+spansize < length {
		upper = lower + spansize
	} else {
		upper = length - 1
	}

	if array[upper] == min {
		return upper
	}

	if array[upper] < min {
		// means
		// array
		// has no
		// item
		// >= min
		// pos = array.length;
		return length
	}

	// we know that the next-smallest span was too small
	lower += (spansize >> 1)

	mid := 0
	for lower+1 != upper {
		mid = (lower + upper) >> 1
		if array[mid] == min {
			return mid
		} else if array[mid] < min {
			lower = mid
		} else {
			upper = mid
		}
	}
	return upper
}

func onesidedgallopingintersect2by2(
	smallset []uint16,