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// 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
// disclaimer in the documentation and/or other materials provided
// with the distribution.
// * Neither the name of Google Inc. nor the names of its
// contributors may be used to endorse or promote products derived
// from this software without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
// Flags: --allow-natives-syntax --expose-gc
// Flags: --noincremental-marking
// Check that objects that are used for prototypes are in the fast mode.
function Super() {
}
function Sub() {
}
function AddProps(obj) {
for (var i = 0; i < 26; i++) {
obj["x" + i] = 0;
}
}
%EnsureFeedbackVectorForFunction(AddProps);
function DoProtoMagic(proto, set__proto__) {
var receiver;
if (set__proto__) {
receiver = new Sub();
receiver.__proto__ = proto;
} else {
Sub.prototype = proto;
// Need to instantiate Sub to mark .prototype as prototype. Make sure the
// instantiated object is used so that the allocation is not optimized away.
receiver = new Sub();
}
// Prototypes are made fast when ICs encounter them.
function ic() { return typeof receiver.foo; }
%EnsureFeedbackVectorForFunction(ic);
ic();
ic();
}
%EnsureFeedbackVectorForFunction(DoProtoMagic);
function test(use_new, add_first, set__proto__) {
var proto = use_new ? new Super() : {};
// New object is fast.
assertTrue(use_new || %HasFastProperties(proto));
if (add_first) {
AddProps(proto);
// Adding this many properties makes it slow.
assertFalse(%HasFastProperties(proto));
DoProtoMagic(proto, set__proto__);
// Making it a prototype makes it fast again.
assertEquals(!%IsDictPropertyConstTrackingEnabled(),
%HasFastProperties(proto));
} else {
DoProtoMagic(proto, set__proto__);
// Still fast
assertEquals(!%IsDictPropertyConstTrackingEnabled(),
%HasFastProperties(proto));
AddProps(proto);
assertEquals(!%IsDictPropertyConstTrackingEnabled(),
%HasFastProperties(proto));
}
return proto;
}
%EnsureFeedbackVectorForFunction(test);
// This test fails easily if gc happens at the wrong time.
gc();
function test_fast_prototype() {
for (var i = 0; i < 4; i++) {
var set__proto__ = ((i & 1) != 0);
var use_new = ((i & 2) != 0);
test(use_new, true, set__proto__);
test(use_new, false, set__proto__);
}
var x = {a: 1, b: 2, c: 3};
var o = { __proto__: x };
assertFalse(%HasFastProperties(x));
for (key in x) {
assertTrue(key == 'a');
break;
}
if (!%IsDictPropertyConstTrackingEnabled())
assertTrue(%HasFastProperties(x));
delete x.b;
for (key in x) {
assertTrue(key == 'a');
break;
}
assertEquals(!%IsDictPropertyConstTrackingEnabled(),
%HasFastProperties(x));
x.d = 4;
assertEquals(!%IsDictPropertyConstTrackingEnabled(),
%HasFastProperties(x));
for (key in x) {
assertTrue(key == 'a');
break;
}
}
%EnsureFeedbackVectorForFunction(test_fast_prototype);
test_fast_prototype();
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