1 files changed, 47 insertions, 0 deletions
diff --git a/js/src/jit-test/tests/for-of/iterclose-dynamic-slot.js b/js/src/jit-test/tests/for-of/iterclose-dynamic-slot.js
new file mode 100644
index 0000000000..170d60999d
--- /dev/null
+++ b/js/src/jit-test/tests/for-of/iterclose-dynamic-slot.js
@@ -0,0 +1,47 @@
+var counter = 0;
+const iterable = {
+  [Symbol.iterator]() {
+    return {
+      i: 0,
+
+      // Force the return method into a dynamic slot.
+      x0: 0, x1: 0, x2: 0, x3: 0, x4: 0, x5: 0, x6: 0, x7: 0, x8: 0,
+      x9: 0, x10: 0, x11: 0, x12: 0, x13: 0, x14: 0, x15: 0, x16: 0,
+      x17: 0, x18: 0, x19: 0, x20: 0, x21: 0, x22: 0, x23: 0, x24: 0,
+
+      next() {
+        return { value: this.i++, done: false }
+      },
+      return() {
+        counter += 1;
+        return { value: undefined, done: true };
+      }
+    };
+  }
+}
+
+function closeIter(o) {
+  for (var x of o) {
+    if (x == 2) {
+      break;
+    }
+  }
+}
+
+function test() {
+  with ({}) {}
+  counter = 0;
+  for (var i = 0; i < 100; i++) {
+    closeIter(iterable)
+  }
+  assertEq(counter, 100)
+}
+
+with ({}) {}
+
+test();
+
+// Force an IC in Ion.
+closeIter([1,2,3]);
+
+test();