* config/alpha/alpha.h (MASK_LONG_DOUBLE_128): New.
        (TARGET_LONG_DOUBLE_128): New.
        (TARGET_SWITCHES): Add long-double-{128,64}.
        (TARGET_HAS_XFLOATING_LIBS): Default to TARGET_LONG_DOUBLE_128.
        (LONG_DOUBLE_TYPE_SIZE): Honor TARGET_LONG_DOUBLE_128.
        (LIBGCC2_LONG_DOUBLE_TYPE_SIZE): New.
        (WIDEST_HARDWARE_FP_SIZE): New.
        (TARGET_CPU_CPP_BUILTINS): Define __LONG_DOUBLE_128__.
        * config/alpha/alpha.c (override_options): Clear MASK_LONG_DOUBLE_128
        if TARGET_VAX_FLOAT.
        * config/alpha/osf5.h (LONG_DOUBLE_TYPE_SIZE): Remove.
        (TARGET_DEFAULT): Set MASK_LONG_DOUBLE_128.

From-SVN: r79026