default S intersect(S s1, S s2) {
			if (!intersects(s1, s2)) {
				return empty();
			}
			return closed(max(s1.min(), s2.min()), min(s1.max(), s2.max()));
		}
Compute the intersection of two spans

@param s1 a span
@param s2 another span
@return the intersection, possibly empty
Ghidra/Framework/Emulation/src/main/java/generic/Span.java