diff options
| author | Jędrzej Nowacki <jedrzej.nowacki@digia.com> | 2014-02-19 11:27:50 +0100 |
|---|---|---|
| committer | The Qt Project <gerrit-noreply@qt-project.org> | 2014-05-16 18:24:14 +0200 |
| commit | 39efc7c3e3a08580f00a19678d2975608d41aa17 (patch) | |
| tree | 9083859152bb7ee394da5edd61bde5975fa47cbe | |
| parent | 7c17b0ad2b74086a52aa6b66c1673335ce65bd5b (diff) | |
Optimize QVector::mid
Change-Id: Iff7d9ec85a095c6712e6045e7708bb88eac629e1
Reviewed-by: Oswald Buddenhagen <oswald.buddenhagen@digia.com>
| -rw-r--r-- | src/corelib/tools/qvector.h | 12 | ||||
| -rw-r--r-- | tests/auto/corelib/tools/qvector/tst_qvector.cpp | 2 |
2 files changed, 9 insertions, 5 deletions
diff --git a/src/corelib/tools/qvector.h b/src/corelib/tools/qvector.h index 9692477e18..c547cec7be 100644 --- a/src/corelib/tools/qvector.h +++ b/src/corelib/tools/qvector.h @@ -833,11 +833,13 @@ Q_OUTOFLINE_TEMPLATE QVector<T> QVector<T>::mid(int pos, int len) const break; } - QVector<T> copy; - copy.reserve(len); - for (int i = pos; i < pos + len; ++i) - copy += at(i); - return copy; + QVector<T> midResult; + midResult.reallocData(0, len); + T *srcFrom = d->begin() + pos; + T *srcTo = d->begin() + pos + len; + midResult.copyConstruct(srcFrom, srcTo, midResult.data()); + midResult.d->size = len; + return midResult; } template <typename T> diff --git a/tests/auto/corelib/tools/qvector/tst_qvector.cpp b/tests/auto/corelib/tools/qvector/tst_qvector.cpp index 776251fa52..97f370f146 100644 --- a/tests/auto/corelib/tools/qvector/tst_qvector.cpp +++ b/tests/auto/corelib/tools/qvector/tst_qvector.cpp @@ -1379,6 +1379,8 @@ void tst_QVector::mid() const list << "foo" << "bar" << "baz" << "bak" << "buck" << "hello" << "kitty"; QCOMPARE(list.mid(3, 3), QVector<QString>() << "bak" << "buck" << "hello"); + QCOMPARE(list.mid(6, 10), QVector<QString>() << "kitty"); + QCOMPARE(list.mid(-1, 20), list); QCOMPARE(list.mid(4), QVector<QString>() << "buck" << "hello" << "kitty"); } |