Elements load depends on the type of the receiver.

test/mjsunit/regress/regress-load-elements.js

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 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
 // Flags: --allow-natives-syntax
 
-// Test optimized closures.
-
-var a = new Array(100);
-
-function f() {
-  var x=0;
-  for (var i=0; i<100; i++) {
-    var g = function goo(y) {
-      function h() {
-        if (goo.arguments[0] == 23) return -42;
-        return 42;
-      }
-      return x + y + h(y);
-    }
-    g(0);
-    %OptimizeFunctionOnNextCall(g);
-    a[i] = g(i);
+function bad_func(o,a) {
+  for (var i = 0; i < 1; ++i) {
+    o.prop = 0;
+    var x = a[0];
   }
 }
 
-f();
-assertEquals(42, a[0]);
-assertEquals(49, a[7]);
-assertEquals(-19, a[23]);
+o = new Object();
+a = {};
+a[0] = 1;
+bad_func(o, a);
 
+o = new Object();
+bad_func(o, a);
 
-
-
+// Optimize. Before the fix, the elements-load and subsequent fixed-array-length
+// were hoisted above the map check. This is invalid since not all types
+// necessarily have elements.
+%OptimizeFunctionOnNextCall(bad_func);
+bad_func(o, "");