alpha.c (function_arg): Don't pass small aggregates in floating point registers.

alpha.c (function_arg): Don't pass small aggregates in floating point registers.

        * config/alpha/alpha.c (function_arg): Don't pass small aggregates
        in floating point registers.  Validate that we don't receive complex
        values here.  Use #elif.
        (return_in_memory, function_value): New.
        (alpha_va_arg): Handle complex values as two arguments.
        * config/alpha/alpha.h (RETURN_IN_MEMORY): Use return_in_memory.
        (FUNCTION_VALUE, LIBCALL_VALUE): Use function_value.
        (SPLIT_COMPLEX_ARGS): New.
        * config/alpha/alpha-protos.h: Update.

From-SVN: r68591