1 files changed, 28 insertions, 0 deletions
diff --git a/js/src/jit-test/tests/ion/spreadcall-not-optimized-static-4b.js b/js/src/jit-test/tests/ion/spreadcall-not-optimized-static-4b.js
new file mode 100644
index 0000000000..bdc2acbc8e
--- /dev/null
+++ b/js/src/jit-test/tests/ion/spreadcall-not-optimized-static-4b.js
@@ -0,0 +1,28 @@
+// Tests when JSOP_OPTIMIZE_SPREADCALL can't be applied during the initial
+// Ion compilation.
+
+// JSOP_OPTIMIZE_SPREADCALL can be optimised when the following conditions
+// are fulfilled:
+//   (1) the argument is an array
+//   (2) the array has no hole
+//   (3) array[@@iterator] is not modified
+//   (4) the array's prototype is Array.prototype
+//   (5) Array.prototype[@@iterator] is not modified
+//   (6) %ArrayIteratorPrototype%.next is not modified
+
+function add(a, b) {
+    return a + b;
+}
+
+// The rest argument's prototype isn't Array.prototype.
+function test() {
+    class MyArray extends Array { }
+    function fn(...rest) {
+        rest = new MyArray(3, 4);
+        return add(...rest);
+    }
+    for (var i = 0; i < 2000; ++i) {
+        assertEq(fn(1, 2), 7);
+    }
+}
+test();