re PR target/30970 (Register zeroing by xor N,N should be moved out of loop)

re PR target/30970 (Register zeroing by xor N,N should be moved out of loop)

        PR target/30970
        * config/i386/sse.md (*mov<mode>_internal, *movv4sf_internal,
        *movv2df_internal): Enable pattern only for valid operand
        combinations.
        * config/i386/i386.c (ix86_modes_tieable_p): For SSE registers,
        tie only 128bit modes. For MMX registers, tie only 64bit modes.

testsuite/ChangeLog:

	PR target/30970
	* gcc.target/i386/gfortran.dg/pr30970.c: New test.

From-SVN: r122387