[turbofan] Set elements kind to holey if constructing array of possibly non-zero length.

test/mjsunit/compiler/regress-621147.js

+// Copyright 2014 the V8 project authors. All rights reserved.

[ahaas, 2016/07/06 07:50:12]

2016

+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+// Flags: --allow-natives-syntax --turbo-filter=test2
+
+function test(n) {
+  return Array(n);
+}
+
+function test2() {
+  return test(2);
+}
+
+function test3(a) {
+  a[0] = 1;
+}
+
+test(0);
+
+var smi_array = [1,2];
+smi_array[2] = 3;
+test3(smi_array);
+
+%OptimizeFunctionOnNextCall(test2);
+
+var broken_array = test2();
+test3(broken_array);
+1+broken_array[0];