CPU Loading issues

Hi All,

I am working with Qt-4.2.2 for my project. I am using stacked widgets in my project, where each screen has some data widgets (like labels, tableWidgets etc) to display.
As I am experiencing some CPU loading issues for my Qt project. I have done profiling to it and I have seen Qt is spending most of the time in blit_16_to_16 function.

Profiling Output:

CPU: CPU with timer interrupt, speed 0 MHz (estimated)
Profiling through timer interrupt
samples % symbol name
5655 15.6818 blit_16_to_16(blit_data const*)
1476 4.0931 qt_intersect_spans(QClipData const*, int*, QT_FT_Span_ const*, QT_FT_Span_ const*, QT_FT_Span_**, int)
1418 3.9322 blend_color_rgb16(int, QT_FT_Span_ const*, void*)
797 2.2101 QWidgetPrivate::subtractOpaqueChildren(QRegion&, QRegion const&, QPoint const&, int) const
650 1.8025 miRegionOp(QRegionPrivate&, QRegionPrivate const*, QRegionPrivate const*, void (*)(QRegionPrivate&, QRect const*, QRect const*, QRect const*, QRect const*, int, int), void (*)(QRegionPrivate&, QRect const*, QRect const*, int, int), void (*)(QRegionPrivate&, QRect const*, QRect const*, int, int))

So my question is, is it normal for Qt to spend 15% of its time in blit_16_to_16 function?
Or do i need to focus on some thing else, please give me some addvice on this.

Thanks & Regards,
Arun.