blob: 87a566bc095325e4e2109dfd7268f675ad520039 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
|
// Copyright 2017 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.
#include "src/heap/marking-inl.h"
namespace v8 {
namespace internal {
namespace {
constexpr MarkBit::CellType kAllBitsSetInCellValue =
std::numeric_limits<MarkBit::CellType>::max();
}
bool MarkingBitmap::AllBitsSetInRange(MarkBitIndex start_index,
MarkBitIndex end_index) const {
if (start_index >= end_index) return false;
end_index--;
const CellIndex start_cell_index = IndexToCell(start_index);
MarkBit::CellType start_index_mask = IndexInCellMask(start_index);
const CellIndex end_cell_index = IndexToCell(end_index);
MarkBit::CellType end_index_mask = IndexInCellMask(end_index);
MarkBit::CellType matching_mask;
if (start_cell_index != end_cell_index) {
matching_mask = ~(start_index_mask - 1);
if ((cells()[start_cell_index] & matching_mask) != matching_mask) {
return false;
}
for (unsigned int i = start_cell_index + 1; i < end_cell_index; i++) {
if (cells()[i] != kAllBitsSetInCellValue) return false;
}
matching_mask = end_index_mask | (end_index_mask - 1);
return ((cells()[end_cell_index] & matching_mask) == matching_mask);
} else {
matching_mask = end_index_mask | (end_index_mask - start_index_mask);
return (cells()[end_cell_index] & matching_mask) == matching_mask;
}
}
bool MarkingBitmap::AllBitsClearInRange(MarkBitIndex start_index,
MarkBitIndex end_index) const {
if (start_index >= end_index) return true;
end_index--;
const CellIndex start_cell_index = IndexToCell(start_index);
MarkBit::CellType start_index_mask = IndexInCellMask(start_index);
const CellIndex end_cell_index = IndexToCell(end_index);
MarkBit::CellType end_index_mask = IndexInCellMask(end_index);
MarkBit::CellType matching_mask;
if (start_cell_index != end_cell_index) {
matching_mask = ~(start_index_mask - 1);
if ((cells()[start_cell_index] & matching_mask)) return false;
for (size_t i = start_cell_index + 1; i < end_cell_index; i++) {
if (cells()[i]) return false;
}
matching_mask = end_index_mask | (end_index_mask - 1);
return !(cells()[end_cell_index] & matching_mask);
} else {
matching_mask = end_index_mask | (end_index_mask - start_index_mask);
return !(cells()[end_cell_index] & matching_mask);
}
}
namespace {
void PrintWord(MarkBit::CellType word, MarkBit::CellType himask = 0) {
for (MarkBit::CellType mask = 1; mask != 0; mask <<= 1) {
if ((mask & himask) != 0) PrintF("[");
PrintF((mask & word) ? "1" : "0");
if ((mask & himask) != 0) PrintF("]");
}
}
class CellPrinter final {
public:
CellPrinter() = default;
void Print(size_t pos, MarkBit::CellType cell) {
if (cell == seq_type) {
seq_length++;
return;
}
Flush();
if (IsSeq(cell)) {
seq_start = pos;
seq_length = 0;
seq_type = cell;
return;
}
PrintF("%zu: ", pos);
PrintWord(cell);
PrintF("\n");
}
void Flush() {
if (seq_length > 0) {
PrintF("%zu: %dx%zu\n", seq_start, seq_type == 0 ? 0 : 1,
seq_length * MarkingBitmap::kBitsPerCell);
seq_length = 0;
}
}
static bool IsSeq(MarkBit::CellType cell) {
return cell == 0 || cell == kAllBitsSetInCellValue;
}
private:
size_t seq_start = 0;
MarkBit::CellType seq_type = 0;
size_t seq_length = 0;
};
} // anonymous namespace
void MarkingBitmap::Print() const {
CellPrinter printer;
for (size_t i = 0; i < kCellsCount; i++) {
printer.Print(i, cells()[i]);
}
printer.Flush();
PrintF("\n");
}
bool MarkingBitmap::IsClean() const {
for (size_t i = 0; i < kCellsCount; i++) {
if (cells()[i] != 0) {
return false;
}
}
return true;
}
// static
MarkBit MarkBit::FromForTesting(Address address) {
return MarkingBitmap::MarkBitFromAddress(address);
}
// static
MarkBit MarkBit::FromForTesting(Tagged<HeapObject> heap_object) {
return MarkingBitmap::MarkBitFromAddress(heap_object.ptr());
}
} // namespace internal
} // namespace v8
|
