diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/ion/mod-double.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/ion/mod-double.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,13 @@
+function test1() {
+    function mod(x, y) {
+        return x % y;
+    }
+    for (var i=0; i<60; i++) {
+        assertEq(mod(4, 2), 0);
+        assertEq(mod(5.5, 2.5), 0.5);
+        assertEq(mod(10.3, 0), NaN);
+        assertEq(mod(-0, -3), -0);
+
+    }
+}
+test1();