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Stop using QVector in QFileInfoPrivate 

This was added in 32629676b9 for Qt 5.1
because QDateTime always allocated memory, so QVector was much faster
for default-created objects. Since Qt 5.7, QDateTime no longer allocates
memory in the default constructor, and in Qt 5.8 on 64-bit systems, it
won't allocate memory at all for most reasonable dates, so construction
times are acceptable now.

Change-Id: If0ad4d988da143b3b1b2fffd1480e83121cddc8c
Reviewed-by: Lars Knoll <lars.knoll@qt.io>
bb10
Thiago Macieira 2016-10-25 15:52:55 -07:00
parent 0b7d9d2811
commit 49ab284d34
2 changed files with 15 additions and 16 deletions
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21
src/corelib/io/qfileinfo.cpp
View File

@ -186,17 +186,22 @@ uint QFileInfoPrivate::getFileFlags(QAbstractFileEngine::FileFlags request) cons
QDateTime &QFileInfoPrivate::getFileTime(QAbstractFileEngine::FileTime request) const
{
Q_ASSERT(fileEngine); // should never be called when using the native FS
if (fileTimes.size() != 3)
fileTimes.resize(3);
if (!cache_enabled)
clearFlags();
uint cf;
if (request == QAbstractFileEngine::CreationTime)
cf = CachedCTime;
else if (request == QAbstractFileEngine::ModificationTime)
cf = CachedMTime;
else
uint cf = 0;
switch (request) {
case QAbstractFileEngine::AccessTime:
cf = CachedATime;
break;
case QAbstractFileEngine::CreationTime:
cf = CachedCTime;
break;
case QAbstractFileEngine::ModificationTime:
cf = CachedMTime;
break;
}
if (!getCachedFlag(cf)) {
fileTimes[request] = fileEngine->fileTime(request);
setCachedFlag(cf);

10
src/corelib/io/qfileinfo_p.h
View File

@ -56,7 +56,6 @@
#include "qatomic.h"
#include "qshareddata.h"
#include "qfilesystemengine_p.h"
#include "qvector.h"
#include <QtCore/private/qabstractfileengine_p.h>
#include <QtCore/private/qfilesystementry_p.h>
@ -158,19 +157,14 @@ public:
QScopedPointer<QAbstractFileEngine> const fileEngine;
mutable QString fileNames[QAbstractFileEngine::NFileNames];
mutable QString fileOwners[2];
mutable QString fileOwners[2]; // QAbstractFileEngine::FileOwner: OwnerUser and OwnerGroup
mutable QDateTime fileTimes[4]; // QAbstractFileEngine::FileTime: BirthTime, MetadataChangeTime, ModificationTime, AccessTime
mutable uint cachedFlags : 30;
bool const isDefaultConstructed : 1; // QFileInfo is a default constructed instance
bool cache_enabled : 1;
mutable uint fileFlags;
mutable qint64 fileSize;
// ### Qt6: FIXME: This vector is essentially a plain array
// mutable QDateTime fileTimes[3], but the array is slower
// to initialize than the QVector as QDateTime has a pimpl.
// In Qt 6, QDateTime should inline its data members,
// and this here can be an array again.
mutable QVector<QDateTime> fileTimes;
inline bool getCachedFlag(uint c) const
{ return cache_enabled ? (cachedFlags & c) : 0; }
inline void setCachedFlag(uint c) const