blob: 9561917777d4e83ebe02ea07107c808e953d4aaf (
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
|
// Copyright (C) 2017 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
#include "qv4functiontable_p.h"
#include "qv4function_p.h"
#include <assembler/MacroAssemblerCodeRef.h>
#include <QtCore/qfile.h>
#include <QtCore/qcoreapplication.h>
QT_BEGIN_NAMESPACE
namespace QV4 {
void generateFunctionTable(Function *function, JSC::MacroAssemblerCodeRef *codeRef)
{
// This implements writing of JIT'd addresses so that perf can find the
// symbol names.
//
// Perf expects the mapping to be in a certain place and have certain
// content, for more information, see:
// https://github.com/torvalds/linux/blob/master/tools/perf/Documentation/jit-interface.txt
static bool doProfile = !qEnvironmentVariableIsEmpty("QV4_PROFILE_WRITE_PERF_MAP");
if (Q_UNLIKELY(doProfile)) {
static QFile perfMapFile(QString::fromLatin1("/tmp/perf-%1.map")
.arg(QCoreApplication::applicationPid()));
static const bool isOpen = perfMapFile.open(QIODevice::WriteOnly);
if (!isOpen) {
qWarning("QV4::JIT::Assembler: Cannot write perf map file.");
doProfile = false;
} else {
const void *address = codeRef->code().executableAddress();
perfMapFile.write(QByteArray::number(reinterpret_cast<quintptr>(address), 16));
perfMapFile.putChar(' ');
perfMapFile.write(QByteArray::number(static_cast<qsizetype>(codeRef->size()), 16));
perfMapFile.putChar(' ');
perfMapFile.write(Function::prettyName(function, address).toUtf8());
perfMapFile.putChar('\n');
perfMapFile.flush();
}
}
}
void destroyFunctionTable(Function *function, JSC::MacroAssemblerCodeRef *codeRef)
{
Q_UNUSED(function);
Q_UNUSED(codeRef);
// It's not advisable to remove things from the perf map file, as it's primarily used to analyze
// a trace after the application has terminated. We want to know about all functions that were
// ever jitted then. If the memory ranges overlap, we will have a problem when analyzing the
// trace. The JIT should try to avoid this.
}
size_t exceptionHandlerSize()
{
return 0;
}
} // QV4
QT_END_NAMESPACE
|
