diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/ion/compare-string.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/ion/compare-string.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,40 @@
+function compareToAtom(a) {
+    return a == 'test';
+}
+
+function compareToAtomNe(a) {
+    return a != 'test';
+}
+
+var st = 'st';
+
+function compareToRope(a) {
+    return a == ('te' + st);
+}
+
+function compareToRopeNe(a) {
+    var st = 'st';
+    return a != ('te' + st);
+}
+
+function main() {
+    var test = 'test';
+    var foobar = 'foobar';
+
+    assertEq(compareToAtom(test), true);
+    assertEq(compareToAtom(foobar), false);
+
+    assertEq(compareToAtomNe(test), false);
+    assertEq(compareToAtomNe(foobar), true);
+
+
+    assertEq(compareToRope(test), true);
+    assertEq(compareToRope(foobar), false);
+
+    assertEq(compareToRopeNe(test), false);
+    assertEq(compareToRopeNe(foobar), true);
+}
+
+for (var i = 0; i < 100000; i++) {
+    main();
+}