blob: d99f118bff2708cd79a7ea31c229505ad4959d7b (
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
|
// Copyright 2006-2008 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.
#ifndef V8_SNAPSHOT_SNAPSHOT_H_
#define V8_SNAPSHOT_SNAPSHOT_H_
#include "src/snapshot/serialize.h"
namespace v8 {
namespace internal {
// Forward declarations.
class Isolate;
class PartialSerializer;
class StartupSerializer;
class Snapshot : public AllStatic {
public:
class Metadata {
public:
explicit Metadata(uint32_t data = 0) : data_(data) {}
bool embeds_script() { return EmbedsScriptBits::decode(data_); }
void set_embeds_script(bool v) {
data_ = EmbedsScriptBits::update(data_, v);
}
uint32_t& RawValue() { return data_; }
private:
class EmbedsScriptBits : public BitField<bool, 0, 1> {};
uint32_t data_;
};
// Initialize the Isolate from the internal snapshot. Returns false if no
// snapshot could be found.
static bool Initialize(Isolate* isolate);
// Create a new context using the internal partial snapshot.
static MaybeHandle<Context> NewContextFromSnapshot(
Isolate* isolate, Handle<JSGlobalProxy> global_proxy);
static bool HaveASnapshotToStartFrom(Isolate* isolate);
static bool EmbedsScript(Isolate* isolate);
static uint32_t SizeOfFirstPage(Isolate* isolate, AllocationSpace space);
// To be implemented by the snapshot source.
static const v8::StartupData* DefaultSnapshotBlob();
static v8::StartupData CreateSnapshotBlob(
const StartupSerializer& startup_ser,
const PartialSerializer& context_ser, Snapshot::Metadata metadata);
#ifdef DEBUG
static bool SnapshotIsValid(v8::StartupData* snapshot_blob);
#endif // DEBUG
private:
static Vector<const byte> ExtractStartupData(const v8::StartupData* data);
static Vector<const byte> ExtractContextData(const v8::StartupData* data);
static Metadata ExtractMetadata(const v8::StartupData* data);
// Snapshot blob layout:
// [0] metadata
// [1 - 6] pre-calculated first page sizes for paged spaces
// [7] serialized start up data length
// ... serialized start up data
// ... serialized context data
static const int kNumPagedSpaces = LAST_PAGED_SPACE - FIRST_PAGED_SPACE + 1;
static const int kMetadataOffset = 0;
static const int kFirstPageSizesOffset = kMetadataOffset + kInt32Size;
static const int kStartupLengthOffset =
kFirstPageSizesOffset + kNumPagedSpaces * kInt32Size;
static const int kStartupDataOffset = kStartupLengthOffset + kInt32Size;
static int ContextOffset(int startup_length) {
return kStartupDataOffset + startup_length;
}
DISALLOW_IMPLICIT_CONSTRUCTORS(Snapshot);
};
#ifdef V8_USE_EXTERNAL_STARTUP_DATA
void SetSnapshotFromFile(StartupData* snapshot_blob);
#endif
} // namespace internal
} // namespace v8
#endif // V8_SNAPSHOT_SNAPSHOT_H_
|
