diff -r 000000000000 -r 6474c204b198 js/src/jit-test/tests/basic/shapelessCalleeTest.js
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jit-test/tests/basic/shapelessCalleeTest.js	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,67 @@
+// The following functions use a delay line of length 2 to change the value
+// of the callee without exiting the traced loop. This is obviously tuned to
+// match the current 8 setting of 2.
+function shapelessArgCalleeLoop(f, g, h, a)
+{
+  for (var i = 0; i < 10; i++) {
+    f(i, a);
+    f = g;
+    g = h;
+  }
+}
+
+function shapelessVarCalleeLoop(f0, g, h, a)
+{
+  var f = f0;
+  for (var i = 0; i < 10; i++) {
+    f(i, a);
+    f = g;
+    g = h;
+  }
+}
+
+function shapelessLetCalleeLoop(f0, g, h, a)
+{
+  for (var i = 0; i < 10; i++) {
+    let f = f0;
+    f(i, a);
+    f = g;
+    g = h;
+  }
+}
+
+function shapelessUnknownCalleeLoop(n, f, g, h, a)
+{
+  for (var i = 0; i < 10; i++) {
+    (n || f)(i, a);
+    f = g;
+    g = h;
+  }
+}
+
+function shapelessCalleeTest()
+{
+  var a = [];
+
+  var helper = function (i, a) a[i] = i;
+  shapelessArgCalleeLoop(helper, helper, function (i, a) a[i] = -i, a);
+
+  helper = function (i, a) a[10 + i] = i;
+  shapelessVarCalleeLoop(helper, helper, function (i, a) a[10 + i] = -i, a);
+
+  helper = function (i, a) a[20 + i] = i;
+  shapelessLetCalleeLoop(helper, helper, function (i, a) a[20 + i] = -i, a);
+
+  helper = function (i, a) a[30 + i] = i;
+  shapelessUnknownCalleeLoop(null, helper, helper, function (i, a) a[30 + i] = -i, a);
+
+  try {
+    helper = {hack: 42};
+    shapelessUnknownCalleeLoop(null, helper, helper, helper, a);
+  } catch (e) {
+    if (e + "" != "TypeError: f is not a function")
+      print("shapelessUnknownCalleeLoop: unexpected exception " + e);
+  }
+  return a.join("");
+}
+assertEq(shapelessCalleeTest(), "01-2-3-4-5-6-7-8-901-2-3-4-5-6-7-8-9012345678901-2-3-4-5-6-7-8-9");