1// Copyright 2012 the V8 project authors. All rights reserved.
2// Redistribution and use in source and binary forms, with or without
3// modification, are permitted provided that the following conditions are
4// met:
5//
6//     * Redistributions of source code must retain the above copyright
7//       notice, this list of conditions and the following disclaimer.
8//     * Redistributions in binary form must reproduce the above
9//       copyright notice, this list of conditions and the following
10//       disclaimer in the documentation and/or other materials provided
11//       with the distribution.
12//     * Neither the name of Google Inc. nor the names of its
13//       contributors may be used to endorse or promote products derived
14//       from this software without specific prior written permission.
15//
16// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
17// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
18// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
19// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
20// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
21// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
22// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
26// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27
28// Flags: --allow-natives-syntax --expose-gc
29// Flags: --noincremental-marking
30
31// Check that objects that are used for prototypes are in the fast mode.
32
33function Super() {
34}
35
36
37function Sub() {
38}
39
40
41function AddProps(obj) {
42  for (var i = 0; i < 26; i++) {
43    obj["x" + i] = 0;
44  }
45}
46
47
48function DoProtoMagic(proto, set__proto__) {
49  if (set__proto__) {
50    (new Sub()).__proto__ = proto;
51  } else {
52    Sub.prototype = proto;
53    // Need to instantiate Sub to mark .prototype as prototype.
54    new Sub();
55  }
56}
57
58
59function test(use_new, add_first, set__proto__, same_map_as) {
60  var proto = use_new ? new Super() : {};
61
62  // New object is fast.
63  assertTrue(%HasFastProperties(proto));
64
65  if (add_first) {
66    AddProps(proto);
67    // Adding this many properties makes it slow.
68    assertFalse(%HasFastProperties(proto));
69    DoProtoMagic(proto, set__proto__);
70    // Making it a prototype makes it fast again.
71    assertTrue(%HasFastProperties(proto));
72  } else {
73    DoProtoMagic(proto, set__proto__);
74    // Still fast
75    assertTrue(%HasFastProperties(proto));
76    AddProps(proto);
77    if (set__proto__) {
78      // After we add all those properties it went slow mode again :-(
79      assertFalse(%HasFastProperties(proto));
80    } else {
81      // .prototype keeps it fast.
82      assertTrue(%HasFastProperties(proto));
83    }
84  }
85  if (same_map_as && !add_first && set__proto__) {
86    assertTrue(%HaveSameMap(same_map_as, proto));
87  }
88  return proto;
89}
90
91// TODO(mstarzinger): This test fails easily if gc happens at the wrong time.
92gc();
93
94for (var i = 0; i < 4; i++) {
95  var set__proto__ = ((i & 1) != 0);
96  var use_new = ((i & 2) != 0);
97
98  test(use_new, true, set__proto__);
99
100  var last = test(use_new, false, set__proto__);
101  test(use_new, false, set__proto__, last);
102}
103
104
105var x = {a: 1, b: 2, c: 3};
106var o = { __proto__: x };
107assertTrue(%HasFastProperties(x));
108for (key in x) {
109  assertTrue(key == 'a');
110  break;
111}
112delete x.b;
113for (key in x) {
114  assertTrue(key == 'a');
115  break;
116}
117assertFalse(%HasFastProperties(x));
118x.d = 4;
119assertFalse(%HasFastProperties(x));
120for (key in x) {
121  assertTrue(key == 'a');
122  break;
123}
124