These blocks depended on the compiler keeping xmm registers untouched between
them.
Originally committed as revision 25619 to svn://svn.ffmpeg.org/ffmpeg/trunk
causes no significant speed difference and can avoid compilation issues with
--enable-pic.
Originally committed as revision 21003 to svn://svn.ffmpeg.org/ffmpeg/trunk
corresponding dsputil functions and remove their dependency on the FLAC
encoder.
Fixes Issue1486.
Originally committed as revision 20266 to svn://svn.ffmpeg.org/ffmpeg/trunk