Re: [Qemu-devel] [PATCH 5/8] tcg: Implement concat*_i64 with deposit_i64

[Aurelien Jarno <aurelien@aurel32.net>]

On Fri, Sep 21, 2012 at 05:18:13PM -0700, Richard Henderson wrote:
> For tcg_gen_concat_i32_i64 we only use deposit if the host supports it.
> For tcg_gen_concat32_i64 even if the host does not, as we get identical
> code before and after.
> 
> Note that this relies on the ANDI -> EXTU patch for the identity claim.

I don't really get why, andi is not used in this patch.
 
> Signed-off-by: Richard Henderson <rth@twiddle.net>
> ---
>  tcg/tcg-op.h | 60 ++++++++++++++++++++++++++++++------------------------------
>  1 file changed, 30 insertions(+), 30 deletions(-)
> 
> diff --git a/tcg/tcg-op.h b/tcg/tcg-op.h
> index bcfb60b..d2fb283 100644
> --- a/tcg/tcg-op.h
> +++ b/tcg/tcg-op.h
> @@ -1809,36 +1809,6 @@ static inline void tcg_gen_discard_i64(TCGv_i64 arg)
>  #endif
>  }
>  
> -static inline void tcg_gen_concat_i32_i64(TCGv_i64 dest, TCGv_i32 low, TCGv_i32 high)
> -{
> -#if TCG_TARGET_REG_BITS == 32
> -    tcg_gen_mov_i32(TCGV_LOW(dest), low);
> -    tcg_gen_mov_i32(TCGV_HIGH(dest), high);
> -#else
> -    TCGv_i64 tmp = tcg_temp_new_i64();
> -    /* This extension is only needed for type correctness.
> -       We may be able to do better given target specific information.  */
> -    tcg_gen_extu_i32_i64(tmp, high);
> -    tcg_gen_shli_i64(tmp, tmp, 32);
> -    tcg_gen_extu_i32_i64(dest, low);
> -    tcg_gen_or_i64(dest, dest, tmp);
> -    tcg_temp_free_i64(tmp);
> -#endif
> -}
> -
> -static inline void tcg_gen_concat32_i64(TCGv_i64 dest, TCGv_i64 low, TCGv_i64 high)
> -{
> -#if TCG_TARGET_REG_BITS == 32
> -    tcg_gen_concat_i32_i64(dest, TCGV_LOW(low), TCGV_LOW(high));
> -#else
> -    TCGv_i64 tmp = tcg_temp_new_i64();
> -    tcg_gen_ext32u_i64(dest, low);
> -    tcg_gen_shli_i64(tmp, high, 32);
> -    tcg_gen_or_i64(dest, dest, tmp);
> -    tcg_temp_free_i64(tmp);
> -#endif
> -}
> -
>  static inline void tcg_gen_andc_i32(TCGv_i32 ret, TCGv_i32 arg1, TCGv_i32 arg2)
>  {
>      if (TCG_TARGET_HAS_andc_i32) {
> @@ -2181,6 +2151,36 @@ static inline void tcg_gen_deposit_i64(TCGv_i64 ret, TCGv_i64 arg1,
>      tcg_temp_free_i64(t1);
>  }
>  
> +static inline void tcg_gen_concat_i32_i64(TCGv_i64 dest, TCGv_i32 low,
> +                                          TCGv_i32 high)
> +{
> +#if TCG_TARGET_REG_BITS == 32
> +    tcg_gen_mov_i32(TCGV_LOW(dest), low);
> +    tcg_gen_mov_i32(TCGV_HIGH(dest), high);
> +#else
> +    TCGv_i64 tmp = tcg_temp_new_i64();
> +    /* These extensions are only needed for type correctness.
> +       We may be able to do better given target specific information.  */
> +    tcg_gen_extu_i32_i64(tmp, high);
> +    tcg_gen_extu_i32_i64(dest, low);
> +    /* If deposit is available, use it.  Otherwise use the extra
> +       knowledge that we have of the zero-extensions above.  */
> +    if (TCG_TARGET_HAS_deposit_i64 && TCG_TARGET_deposit_i64_valid(32, 32)) {
> +        tcg_gen_deposit_i64(dest, dest, tmp, 32, 32);
> +    } else {
> +        tcg_gen_shli_i64(tmp, tmp, 32);
> +        tcg_gen_or_i64(dest, dest, tmp);
> +    }
> +    tcg_temp_free_i64(tmp);
> +#endif
> +}
> +
> +static inline void tcg_gen_concat32_i64(TCGv_i64 dest, TCGv_i64 low,
> +                                        TCGv_i64 high)
> +{
> +    tcg_gen_deposit_i64(dest, low, high, 32, 32);
> +}
> +
>  static inline void tcg_gen_movcond_i32(TCGCond cond, TCGv_i32 ret,
>                                         TCGv_i32 c1, TCGv_i32 c2,
>                                         TCGv_i32 v1, TCGv_i32 v2)
> -- 
> 1.7.11.4
> 

Reviewed-by: Aurelien Jarno <aurelien@aurel32.net>

-- 
Aurelien Jarno                          GPG: 1024D/F1BCDB73
aurelien@aurel32.net                 http://www.aurel32.net