"Zuxy Meng" <zuxy.meng@xxxxxxxxx> writes: > I found that gcc 4.5 generates "rep ret" even under -march=core2. Does > an Intel CPU benefit from this optimization too? As far as I know no Intel CPU benefits. Note that -march selects the architecture but not the tuning. The default tuning uses "rep; ret" when appropriate. If you want to avoid it, use a -mtune option. Ian
