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
|
/*
* Copyright (C) 2013-2021 Apple Inc. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. 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.
*
* THIS SOFTWARE IS PROVIDED BY APPLE INC. ``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 APPLE INC. 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.
*/
#include "config.h"
#include "VMEntryScope.h"
#include "Options.h"
#include "SamplingProfiler.h"
#include "VM.h"
#include "WasmCapabilities.h"
#include "WasmMachineThreads.h"
#include "Watchdog.h"
#include <wtf/SystemTracing.h>
namespace JSC {
VMEntryScope::VMEntryScope(VM& vm, JSGlobalObject* globalObject)
: m_vm(vm)
, m_globalObject(globalObject)
{
if (!vm.entryScope) {
vm.entryScope = this;
auto& thread = Thread::current();
if (UNLIKELY(!thread.isJSThread())) {
Thread::registerJSThread(thread);
#if ENABLE(WEBASSEMBLY)
if (Wasm::isSupported())
Wasm::startTrackingCurrentThread();
#endif
#if HAVE(MACH_EXCEPTIONS)
registerThreadForMachExceptionHandling(thread);
#endif
}
vm.firePrimitiveGigacageEnabledIfNecessary();
// Reset the date cache between JS invocations to force the VM to
// observe time zone changes.
vm.resetDateCacheIfNecessary();
if (UNLIKELY(vm.watchdog()))
vm.watchdog()->enteredVM();
#if ENABLE(SAMPLING_PROFILER)
{
SamplingProfiler* samplingProfiler = vm.samplingProfiler();
if (UNLIKELY(samplingProfiler))
samplingProfiler->noticeVMEntry();
}
#endif
if (UNLIKELY(Options::useTracePoints()))
tracePoint(VMEntryScopeStart);
}
vm.clearLastException();
}
void VMEntryScope::addDidPopListener(Function<void ()>&& listener)
{
m_didPopListeners.append(WTFMove(listener));
}
VMEntryScope::~VMEntryScope()
{
if (m_vm.entryScope != this)
return;
ASSERT_WITH_MESSAGE(!m_vm.hasCheckpointOSRSideState(), "Exitting the VM but pending checkpoint side state still available");
if (UNLIKELY(Options::useTracePoints()))
tracePoint(VMEntryScopeEnd);
if (UNLIKELY(m_vm.watchdog()))
m_vm.watchdog()->exitedVM();
m_vm.entryScope = nullptr;
for (auto& listener : m_didPopListeners)
listener();
// If the trap bit is still set at this point, then it means that VMTraps::handleTraps()
// has not yet been called for this termination request. As a result, we've not thrown a
// TerminationException yet. Some client code relies on detecting the presence of the
// TerminationException in order to signal that a termination was requested. As a result,
// we want to stay in the TerminationInProgress state until VMTraps::handleTraps() (which
// clears the trap bit) gets called, and the TerminationException gets thrown.
//
// Note: perhaps there's a better way for the client to know that a termination was
// requested (after all, the request came from the client). However, this is how the
// client code currently works. Changing that will take some significant effort to hunt
// down all the places in client code that currently rely on this behavior.
if (!m_vm.traps().needHandling(VMTraps::NeedTermination))
m_vm.setTerminationInProgress(false);
m_vm.clearScratchBuffers();
}
} // namespace JSC
|
