Re: [Qemu-devel] [PATCH v2 1/2] target-ppc: add vextu[bhw]lx instructions

[Richard Henderson <rth@twiddle.net>]

On 11/24/2016 12:32 PM, Nikunj A Dadhania wrote:
> +#if defined(HOST_WORDS_BIGENDIAN)
> +# if defined(CONFIG_INT128)
> +# define VEXTULX_DO(name, size)                                     \
> +    target_ulong glue(helper_, name)(target_ulong a, ppc_avr_t *b)  \
> +    {                                                               \
> +        int index = (a & 0xf) * 8;                                  \
> +        return int128_rshift(b->u128, index) &                      \
> +            MAKE_64BIT_MASK(0, size);                               \
> +    }
> +# else
> +# define VEXTULX_DO(name, size)                                     \
> +    target_ulong glue(helper_, name)(target_ulong a, ppc_avr_t *b)  \
> +    {                                                               \
> +        int index = (a & 0xf) * 8;                                  \
> +        Int128 value = int128_make128(b->u64[LO_IDX],               \
> +                                      b->u64[HI_IDX]);              \
> +        return int128_rshift(value, index) &                        \
> +            MAKE_64BIT_MASK(0, size);                               \
> +    }
> +# endif

Why are these duplicated?

Clearly the missed trick is that you should *never* check CONFIG_INT128 and 
always rely on Int128.


r~