Hi,

The patch below contains some tuning changes for Lakemont, introduced
by H.J. Lu. Bootstraped/regtested for Linux/x86_64. Ok for trunk?

        * gcc/config/i386/x86-tune.def (X86_TUNE_USE_BT): Enable
        for Lakemont.
        (X86_TUNE_ZERO_EXTEND_WITH_AND): Disable for Lakemont.

Julia