Re: [PATCH v2 23/25] target/tricore: Use min/max for saturate

[Philippe Mathieu-Daudé]

On 7/3/23 19:35, Richard Henderson wrote:
> Use tcg_constant_i32 for the bounds.
>
> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
> ---
> Cc: Bastian Koppelmann <kbastian@mail.uni-paderborn.de>
> ---
>   target/tricore/translate.c | 14 +++-----------
>   1 file changed, 3 insertions(+), 11 deletions(-)

>   static void gen_saturate(TCGv ret, TCGv arg, int32_t up, int32_t low)
>   {
> -    TCGv sat_neg = tcg_const_i32(low);
> -    TCGv temp = tcg_const_i32(up);
> -
> -    /* sat_neg = (arg < low ) ? low : arg; */
> -    tcg_gen_movcond_tl(TCG_COND_LT, sat_neg, arg, sat_neg, sat_neg, arg);
> -
> -    /* ret = (sat_neg > up ) ? up  : sat_neg; */
> -    tcg_gen_movcond_tl(TCG_COND_GT, ret, sat_neg, temp, temp, sat_neg);
> +    tcg_gen_smax_tl(ret, arg, tcg_constant_i32(low));

This one is trivial when looking at tcg_gen_smax implementation.

> +    tcg_gen_smin_tl(ret, ret, tcg_constant_i32(up));

OK, when changing TCG_COND_GT -> TCG_COND_LT and inverting the args,
then this becomes obvious this is tcg_gen_smin.

>   }
>   
>   static void gen_saturate_u(TCGv ret, TCGv arg, int32_t up)
>   {
> -    TCGv temp = tcg_const_i32(up);
> -    /* sat_neg = (arg > up ) ? up : arg; */
> -    tcg_gen_movcond_tl(TCG_COND_GTU, ret, arg, temp, temp, arg);
> +    tcg_gen_umin_tl(ret, arg, tcg_constant_i32(up));

Inverting args for TCG_COND_GTU -> TCG_COND_LTU, this is indeed
tcg_gen_umin.

>   }

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>