Edit in JSFiddle

var p1 = document.getElementById("p1");
var range1 = document.createRange();
var range2 = document.createRange();

range1.selectNodeContents(p1);
range2.selectNodeContents(p1);
range2.setEndBefore(p1.lastChild);

var comp1 = range1.compareBoundaryPoints(Range.START_TO_START, range2); // 0
var comp2 = range1.compareBoundaryPoints(Range.END_TO_END, range2); // 1
var comp3 = range2.compareBoundaryPoints(Range.END_TO_END, range1); // -1

document.write("range1 START_TO_START range2 : " + comp1 + "<br>");
document.write("range1 END_TO_END range2 : " + comp2 + "<br>");
document.write("range2 END_TO_END range1 : " + comp3 + "<br>");

<p id="p1"><b>Hello</b> world!</p>