1 // Copyright 2015 the V8 project authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4 
5 #include "src/heap/slots-buffer.h"
6 #include "test/cctest/cctest.h"
7 #include "test/cctest/heap/utils-inl.h"
8 
9 namespace v8 {
10 namespace internal {
11 
TEST(SlotsBufferObjectSlotsRemoval)12 TEST(SlotsBufferObjectSlotsRemoval) {
13   CcTest::InitializeVM();
14   v8::HandleScope scope(CcTest::isolate());
15   Isolate* isolate = CcTest::i_isolate();
16   Heap* heap = isolate->heap();
17   Factory* factory = isolate->factory();
18 
19   SlotsBuffer* buffer = new SlotsBuffer(NULL);
20   void* fake_object[1];
21 
22   Handle<FixedArray> array = factory->NewFixedArray(2, TENURED);
23   CHECK(heap->old_space()->Contains(*array));
24   array->set(0, reinterpret_cast<Object*>(fake_object), SKIP_WRITE_BARRIER);
25 
26   // Firstly, let's test the regular slots buffer entry.
27   buffer->Add(HeapObject::RawField(*array, FixedArray::kHeaderSize));
28   CHECK(reinterpret_cast<void*>(buffer->Get(0)) ==
29         HeapObject::RawField(*array, FixedArray::kHeaderSize));
30   SlotsBuffer::RemoveObjectSlots(CcTest::i_isolate()->heap(), buffer,
31                                  array->address(),
32                                  array->address() + array->Size());
33   CHECK(reinterpret_cast<void*>(buffer->Get(0)) ==
34         HeapObject::RawField(heap->empty_fixed_array(),
35                              FixedArrayBase::kLengthOffset));
36 
37   // Secondly, let's test the typed slots buffer entry.
38   SlotsBuffer::AddTo(NULL, &buffer, SlotsBuffer::EMBEDDED_OBJECT_SLOT,
39                      array->address() + FixedArray::kHeaderSize,
40                      SlotsBuffer::FAIL_ON_OVERFLOW);
41   CHECK(reinterpret_cast<void*>(buffer->Get(1)) ==
42         reinterpret_cast<Object**>(SlotsBuffer::EMBEDDED_OBJECT_SLOT));
43   CHECK(reinterpret_cast<void*>(buffer->Get(2)) ==
44         HeapObject::RawField(*array, FixedArray::kHeaderSize));
45   SlotsBuffer::RemoveObjectSlots(CcTest::i_isolate()->heap(), buffer,
46                                  array->address(),
47                                  array->address() + array->Size());
48   CHECK(reinterpret_cast<void*>(buffer->Get(1)) ==
49         HeapObject::RawField(heap->empty_fixed_array(),
50                              FixedArrayBase::kLengthOffset));
51   CHECK(reinterpret_cast<void*>(buffer->Get(2)) ==
52         HeapObject::RawField(heap->empty_fixed_array(),
53                              FixedArrayBase::kLengthOffset));
54   delete buffer;
55 }
56 
57 
TEST(FilterInvalidSlotsBufferEntries)58 TEST(FilterInvalidSlotsBufferEntries) {
59   FLAG_manual_evacuation_candidates_selection = true;
60   CcTest::InitializeVM();
61   v8::HandleScope scope(CcTest::isolate());
62   Isolate* isolate = CcTest::i_isolate();
63   Heap* heap = isolate->heap();
64   Factory* factory = isolate->factory();
65   SlotsBuffer* buffer = new SlotsBuffer(NULL);
66 
67   // Set up a fake black object that will contain a recorded SMI, a recorded
68   // pointer to a new space object, and a recorded pointer to a non-evacuation
69   // candidate object. These object should be filtered out. Additionally,
70   // we point to an evacuation candidate object which should not be filtered
71   // out.
72 
73   // Create fake object and mark it black.
74   Handle<FixedArray> fake_object = factory->NewFixedArray(23, TENURED);
75   MarkBit mark_bit = Marking::MarkBitFrom(*fake_object);
76   Marking::MarkBlack(mark_bit);
77 
78   // Write a SMI into field one and record its address;
79   Object** field_smi = fake_object->RawFieldOfElementAt(0);
80   *field_smi = Smi::FromInt(100);
81   buffer->Add(field_smi);
82 
83   // Write a new space reference into field 2 and record its address;
84   Handle<FixedArray> new_space_object = factory->NewFixedArray(23);
85   mark_bit = Marking::MarkBitFrom(*new_space_object);
86   Marking::MarkBlack(mark_bit);
87   Object** field_new_space = fake_object->RawFieldOfElementAt(1);
88   *field_new_space = *new_space_object;
89   buffer->Add(field_new_space);
90 
91   // Write an old space reference into field 3 which points to an object not on
92   // an evacuation candidate.
93   Handle<FixedArray> old_space_object_non_evacuation =
94       factory->NewFixedArray(23, TENURED);
95   mark_bit = Marking::MarkBitFrom(*old_space_object_non_evacuation);
96   Marking::MarkBlack(mark_bit);
97   Object** field_old_space_object_non_evacuation =
98       fake_object->RawFieldOfElementAt(2);
99   *field_old_space_object_non_evacuation = *old_space_object_non_evacuation;
100   buffer->Add(field_old_space_object_non_evacuation);
101 
102   // Write an old space reference into field 4 which points to an object on an
103   // evacuation candidate.
104   SimulateFullSpace(heap->old_space());
105   Handle<FixedArray> valid_object =
106       isolate->factory()->NewFixedArray(23, TENURED);
107   Page* page = Page::FromAddress(valid_object->address());
108   page->SetFlag(MemoryChunk::EVACUATION_CANDIDATE);
109   Object** valid_field = fake_object->RawFieldOfElementAt(3);
110   *valid_field = *valid_object;
111   buffer->Add(valid_field);
112 
113   SlotsBuffer::RemoveInvalidSlots(heap, buffer);
114   Object** kRemovedEntry = HeapObject::RawField(heap->empty_fixed_array(),
115                                                 FixedArrayBase::kLengthOffset);
116   CHECK_EQ(buffer->Get(0), kRemovedEntry);
117   CHECK_EQ(buffer->Get(1), kRemovedEntry);
118   CHECK_EQ(buffer->Get(2), kRemovedEntry);
119   CHECK_EQ(buffer->Get(3), valid_field);
120 
121   // Clean-up to make verify heap happy.
122   mark_bit = Marking::MarkBitFrom(*fake_object);
123   Marking::MarkWhite(mark_bit);
124   mark_bit = Marking::MarkBitFrom(*new_space_object);
125   Marking::MarkWhite(mark_bit);
126   mark_bit = Marking::MarkBitFrom(*old_space_object_non_evacuation);
127   Marking::MarkWhite(mark_bit);
128 
129   delete buffer;
130 }
131 
132 }  // namespace internal
133 }  // namespace v8
134