Improve use of QHash to minimize double hashing

Avoid looking up by key twice in a row in various locations, but instead
using iterators and index lookup.

Change-Id: I61a079115199ab9c041ad3a26d36b45ee3f775e0
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

1 files changed, 4 insertions, 5 deletions

diff --git a/src/gui/text/qtextlayout.cpp b/src/gui/text/qtextlayout.cpp
index f5827bb683..28a5eb6a89 100644
--- a/src/gui/text/qtextlayout.cpp
+++ b/src/gui/text/qtextlayout.cpp
@@ -1059,9 +1059,10 @@ QList<QGlyphRun> QTextLayout::glyphRuns(int from, int length) const
                 QGlyphRun::GlyphRunFlags flags = glyphRun.flags();
                 QPair<QFontEngine *, int> key(fontEngine, int(flags));
                 // merge the glyph runs using the same font
-                if (glyphRunHash.contains(key)) {
-                    QGlyphRun &oldGlyphRun = glyphRunHash[key];
-
+                QGlyphRun &oldGlyphRun = glyphRunHash[key];
+                if (oldGlyphRun.isEmpty()) {
+                    oldGlyphRun = glyphRun;
+                } else {
                     QVector<quint32> indexes = oldGlyphRun.glyphIndexes();
                     QVector<QPointF> positions = oldGlyphRun.positions();
                     QRectF boundingRect = oldGlyphRun.boundingRect();
@@ -1073,8 +1074,6 @@ QList<QGlyphRun> QTextLayout::glyphRuns(int from, int length) const
                     oldGlyphRun.setGlyphIndexes(indexes);
                     oldGlyphRun.setPositions(positions);
                     oldGlyphRun.setBoundingRect(boundingRect);
-                } else {
-                    glyphRunHash[key] = glyphRun;
                 }
             }
         }