diff --git a/implementation-contributed/javascriptcore/stress/regress-189028.js b/implementation-contributed/javascriptcore/stress/regress-189028.js
new file mode 100644
index 0000000000..b66db453bd
--- /dev/null
+++ b/implementation-contributed/javascriptcore/stress/regress-189028.js
@@ -0,0 +1,242 @@
+function assert(x, y) {
+    if (x != y) {
+        $vm.print("actual: ", x);
+        $vm.print("expected: ", y);
+        throw "FAILED\n" + new Error().stack;
+    }
+}
+
+(function() {
+    let arr = [1.1, 2.2];
+    let arr2 = [1.1, 2.2];
+
+    assert($vm.isHavingABadTime(arr), false);
+    assert($vm.indexingMode(arr), "CopyOnWriteArrayWithDouble");
+    assert($vm.isHavingABadTime(arr2), false);
+    assert($vm.indexingMode(arr2), "CopyOnWriteArrayWithDouble");
+
+    let o = $vm.createGlobalObject();
+
+    $vm.haveABadTime(o);
+
+    let proto = new o.Object();
+    assert($vm.isHavingABadTime(o), true);
+    assert($vm.isHavingABadTime(proto), true);
+
+    arr2.__proto__ = proto;
+
+    assert($vm.isHavingABadTime(arr), false);
+    assert($vm.indexingMode(arr), "CopyOnWriteArrayWithDouble");
+    assert($vm.isHavingABadTime(arr2), false);
+    assert($vm.indexingMode(arr2), "ArrayWithSlowPutArrayStorage");
+})();
+
+gc();
+
+(function() {
+    let arr = [1.1, 2.2];
+    let arr2 = [1.1, 2.2];
+
+    assert($vm.isHavingABadTime(arr), false);
+    assert($vm.indexingMode(arr), "CopyOnWriteArrayWithDouble");
+    assert($vm.isHavingABadTime(arr2), false);
+    assert($vm.indexingMode(arr2), "CopyOnWriteArrayWithDouble");
+
+    let o = $vm.createGlobalObject();
+
+    let proto = new o.Object();
+    assert($vm.isHavingABadTime(o), false);
+    assert($vm.isHavingABadTime(proto), false);
+
+    arr2.__proto__ = proto;
+
+    assert($vm.isHavingABadTime(arr), false);
+    assert($vm.indexingMode(arr), "CopyOnWriteArrayWithDouble");
+    assert($vm.isHavingABadTime(arr2), false);
+    assert($vm.indexingMode(arr2), "ArrayWithDouble");
+
+    $vm.haveABadTime(o);
+
+    assert($vm.isHavingABadTime(o), true);
+    assert($vm.isHavingABadTime(proto), true);
+
+    assert($vm.isHavingABadTime(arr), false);
+    assert($vm.indexingMode(arr), "CopyOnWriteArrayWithDouble");
+    assert($vm.isHavingABadTime(arr2), false);
+    assert($vm.indexingMode(arr2), "ArrayWithSlowPutArrayStorage");
+})();
+
+gc();
+
+(function() {
+    let arr = [1.1, 2.2];
+    let arr2 = {};
+
+    assert($vm.isHavingABadTime(arr), false);
+    assert($vm.indexingMode(arr), "CopyOnWriteArrayWithDouble");
+    assert($vm.isHavingABadTime(arr2), false);
+    assert($vm.indexingMode(arr2), "NonArray");
+
+    let o = $vm.createGlobalObject();
+
+    $vm.haveABadTime(o);
+
+    let proto = new o.Object();
+    assert($vm.isHavingABadTime(o), true);
+    assert($vm.isHavingABadTime(proto), true);
+
+    arr2.__proto__ = proto;
+
+    assert($vm.isHavingABadTime(arr), false);
+    assert($vm.indexingMode(arr), "CopyOnWriteArrayWithDouble");
+    assert($vm.isHavingABadTime(arr2), false);
+    assert($vm.indexingMode(arr2), "NonArray");
+
+    arr2[0] = 1.1;
+
+    assert($vm.isHavingABadTime(arr), false);
+    assert($vm.indexingMode(arr), "CopyOnWriteArrayWithDouble");
+    assert($vm.isHavingABadTime(arr2), false);
+    assert($vm.indexingMode(arr2), "NonArrayWithSlowPutArrayStorage");
+})();
+
+gc();
+
+(function() {
+    let arr = [1.1, 2.2];
+    let arr2 = {};
+
+    assert($vm.isHavingABadTime(arr), false);
+    assert($vm.indexingMode(arr), "CopyOnWriteArrayWithDouble");
+    assert($vm.isHavingABadTime(arr2), false);
+    assert($vm.indexingMode(arr2), "NonArray");
+
+    let o = $vm.createGlobalObject();
+    let proto = new o.Object();
+
+    assert($vm.isHavingABadTime(o), false);
+    assert($vm.isHavingABadTime(proto), false);
+
+    arr2.__proto__ = proto;
+
+    assert($vm.isHavingABadTime(arr), false);
+    assert($vm.indexingMode(arr), "CopyOnWriteArrayWithDouble");
+    assert($vm.isHavingABadTime(arr2), false);
+    assert($vm.indexingMode(arr2), "NonArray");
+
+    arr2[0] = 1.1;
+
+    assert($vm.isHavingABadTime(arr), false);
+    assert($vm.indexingMode(arr), "CopyOnWriteArrayWithDouble");
+    assert($vm.isHavingABadTime(arr2), false);
+    assert($vm.indexingMode(arr2), "NonArrayWithDouble");
+
+    $vm.haveABadTime(o);
+
+    assert($vm.isHavingABadTime(o), true);
+    assert($vm.isHavingABadTime(proto), true);
+
+    assert($vm.isHavingABadTime(arr), false);
+    assert($vm.indexingMode(arr), "CopyOnWriteArrayWithDouble");
+    assert($vm.isHavingABadTime(arr2), false);
+    assert($vm.indexingMode(arr2), "NonArrayWithSlowPutArrayStorage");
+})();
+
+gc();
+
+(function() {
+    let g0 = $vm.createGlobalObject();
+    let o0 = new g0.Object(); 
+    assert($vm.isHavingABadTime(g0), false);
+    assert($vm.isHavingABadTime(o0), false);
+
+    let g1 = $vm.createGlobalObject();
+    let o1 = new g1.Object();
+    assert($vm.isHavingABadTime(g1), false);
+    assert($vm.isHavingABadTime(o1), false);
+
+    let g2 = $vm.createGlobalObject();
+    assert($vm.isHavingABadTime(g2), false);
+
+    $vm.haveABadTime(g1);
+    assert($vm.isHavingABadTime(g1), true);
+
+    o1.__proto__ = null;
+    g2.Array.prototype.__proto__ = o1;
+    o0.__proto__ = o1;
+
+    assert($vm.indexingMode(o0), "NonArray");
+    assert($vm.isHavingABadTime(g0), false);
+    assert($vm.isHavingABadTime(g2), true);
+})();
+
+gc();
+
+(function() {
+    let g0 = $vm.createGlobalObject();
+    let o0 = new g0.Object(); 
+    assert($vm.isHavingABadTime(g0), false);
+    assert($vm.isHavingABadTime(o0), false);
+
+    let g1 = $vm.createGlobalObject();
+    let o1 = new g1.Object();
+    assert($vm.isHavingABadTime(g1), false);
+    assert($vm.isHavingABadTime(o1), false);
+
+    let g2 = $vm.createGlobalObject();
+    assert($vm.isHavingABadTime(g2), false);
+
+    o1.__proto__ = null;
+    g2.Array.prototype.__proto__ = o1;
+    o0.__proto__ = o1;
+    assert($vm.isHavingABadTime(g0), false);
+    assert($vm.isHavingABadTime(g1), false);
+    assert($vm.isHavingABadTime(g2), false);
+
+    $vm.haveABadTime(g1);
+
+    assert($vm.indexingMode(o0), "NonArray");
+    assert($vm.isHavingABadTime(g0), false);
+    assert($vm.isHavingABadTime(g1), true);
+    assert($vm.isHavingABadTime(g2), true);
+})();
+
+gc();
+
+(function() {
+    let g0 = $vm.createGlobalObject();
+    let o0 = new g0.Object(); 
+    assert($vm.isHavingABadTime(g0), false);
+    assert($vm.isHavingABadTime(o0), false);
+
+    let g1 = $vm.createGlobalObject();
+    let o1 = new g1.Object();
+    assert($vm.isHavingABadTime(g1), false);
+    assert($vm.isHavingABadTime(o1), false);
+
+    let g2 = $vm.createGlobalObject();
+    let o2 = new g2.Object();
+    assert($vm.isHavingABadTime(g2), false);
+    assert($vm.isHavingABadTime(o2), false);
+
+    let g3 = $vm.createGlobalObject();
+    assert($vm.isHavingABadTime(g3), false);
+
+    o1.__proto__ = null;
+    g2.Array.prototype.__proto__ = o1;
+    o2.__proto__ = o1;
+    g3.Array.prototype.__proto__ = o2;
+    o0.__proto__ = o1;
+    assert($vm.isHavingABadTime(g0), false);
+    assert($vm.isHavingABadTime(g1), false);
+    assert($vm.isHavingABadTime(g2), false);
+    assert($vm.isHavingABadTime(g3), false);
+
+    $vm.haveABadTime(g1);
+
+    assert($vm.indexingMode(o0), "NonArray");
+    assert($vm.isHavingABadTime(g0), false);
+    assert($vm.isHavingABadTime(g1), true);
+    assert($vm.isHavingABadTime(g2), true);
+    assert($vm.isHavingABadTime(g2), true);
+})();
\ No newline at end of file