* Makefile.in (RTL_BASE_H): Add real.h.
        * real.h (REAL_VALUE_FROM_CONST_DOUBLE): Use structure copy
        instead of memcpy.
        * emit-rtl.c (const_double_from_real_value): Likewise; use rtx.u.rv
        directly.
        * rtl.c (rtl_check_failed_code_mode): New.
        * rtl.h (struct rtx_def): Add u.rv.
        (XCMWINT, XCNMPRV): New.
        (CONST_DOUBLE_LOW, CONST_DOUBLE_HIGH): Use XCMWINT.
        (CONST_DOUBLE_REAL_VALUE): Use XCNMPRV; constify.

Co-Authored-By: Richard Henderson <rth@redhat.com>

From-SVN: r102643