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QDateTimePrivate: enable read caching on m_status in setDateTime() 

Help the compiler by building the new status flags in a local
instead of a member variable. Enables value tracking for that
piece of data across several non-inline function calls, leading
to less redundant reads through this->.

Effects on Linux GCC 4.9 stripped release builds:
 text   -248B
 data    +-0B
 relocs  +-0

Change-Id: I2db21439464ad0fff8163a908de3b15df7c4ab6d
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@theqtcompany.com>
bb10
Marc Mutz 2015-01-22 09:33:11 +01:00
parent 9a34fed728
commit db569428c6
1 changed files with 6 additions and 6 deletions
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12
src/corelib/tools/qdatetime.cpp
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@ -2682,29 +2682,29 @@ void QDateTimePrivate::setDateTime(const QDate &date, const QTime &time)
if (!useTime.isValid() && date.isValid())
useTime = QTime::fromMSecsSinceStartOfDay(0);
// Reset the status
m_status = 0;
StatusFlags newStatus;
// Set date value and status
qint64 days = 0;
if (date.isValid()) {
days = date.toJulianDay() - JULIAN_DAY_FOR_EPOCH;
m_status = ValidDate;
newStatus = ValidDate;
} else if (date.isNull()) {
m_status = NullDate;
newStatus = NullDate;
}
// Set time value and status
int ds = 0;
if (useTime.isValid()) {
ds = useTime.msecsSinceStartOfDay();
m_status = m_status | ValidTime;
newStatus |= ValidTime;
} else if (time.isNull()) {
m_status = m_status | NullTime;
newStatus |= NullTime;
}
// Set msecs serial value
m_msecs = (days * MSECS_PER_DAY) + ds;
m_status = newStatus;
// Set if date and time are valid
checkValidDateTime();