Array() in optimized code can create with wrong ElementsKind in corner cases.

test/mjsunit/array-constructor-feedback.js

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
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@@ skipping 198 matching lines @@
   a = bar(100);
   assertTrue(isHoley(a));
   a = bar(0);
   assertOptimized(bar);
   // Crankshafted functions don't use mementos, so feedback still
   // indicates a packed array is desired. (unless --nocrankshaft is in use).
   if (4 != %GetOptimizationStatus(bar)) {
     assertFalse(isHoley(a));
   }
 })();
+
+// Test: Make sure that crankshaft continues with feedback for large arrays.
+(function() {
+  function bar(len) { return new Array(len); }
+  var size = 100001;
+  // Perform a gc, because we are allocating a very large array and if a gc
+  // happens during the allocation we could lose our memento.
+  gc();
+  bar(size)[0] = 'string';
+  var res = bar(size);
+  assertKind(elements_kind.fast, bar(size));
+    %OptimizeFunctionOnNextCall(bar);
+  assertKind(elements_kind.fast, bar(size));
+  // But there is a limit, based on the size of the old generation, currently
+  // 22937600, but double it to prevent the test being too brittle.
+  var large_size = 22937600 * 2;
+  assertKind(elements_kind.dictionary, bar(large_size));
+})();