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// Copyright 2016 the V8 project authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
// Flags: --allow-natives-syntax --noalways-opt
var elements_kind = {
fast_smi_only : 'fast smi only elements',
fast : 'fast elements',
fast_double : 'fast double elements',
dictionary : 'dictionary elements',
}
function getKind(obj) {
if (%HasFastSmiElements(obj)) return elements_kind.fast_smi_only;
if (%HasFastObjectElements(obj)) return elements_kind.fast;
if (%HasFastDoubleElements(obj)) return elements_kind.fast_double;
if (%HasDictionaryElements(obj)) return elements_kind.dictionary;
}
function assertKind(expected, obj, name_opt) {
assertEquals(expected, getKind(obj), name_opt);
}
(function() {
function make1() { return new Array(); }
function make2() { return new Array(); }
function make3() { return new Array(); }
function foo(a, i) { a[0] = i; }
function run_test(maker_function) {
var one = maker_function();
assertKind(elements_kind.fast_smi_only, one);
// Use memento to pre-transition allocation site to DOUBLE elements.
foo(one, 1.5);
// Newly created arrays should now have DOUBLE elements right away.
var two = maker_function();
assertKind(elements_kind.fast_double, two);
}
// Initialize the KeyedStoreIC in foo; the actual operation will be done
// in the runtime.
run_test(make1);
// Run again; the IC optimistically assumed to only see the transitioned
// (double-elements) map again, so this will make it polymorphic.
// The actual operation will again be done in the runtime.
run_test(make2);
// Finally, check if the initialized IC honors the allocation memento.
run_test(make3);
})();
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