Re: [PATCH 2/5] tcg/ppc: Hoist common argument loads in tcg_out_op()

[Philippe Mathieu-Daudé]

On 1/11/21 4:01 PM, Philippe Mathieu-Daudé wrote:
> Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
> ---
>  tcg/ppc/tcg-target.c.inc | 294 ++++++++++++++++++---------------------
>  1 file changed, 138 insertions(+), 156 deletions(-)
...

> @@ -2818,10 +2805,9 @@ static void tcg_out_op(TCGContext *s, TCGOpcode opc, 
> const TCGArg *args,
>      case INDEX_op_bswap32_i32:
>      case INDEX_op_bswap32_i64:
>          /* Stolen from gcc's builtin_bswap32 */
> -        a1 = args[1];
> -        a0 = args[0] == a1 ? TCG_REG_R0 : args[0];
> +        a0 = a0 == a1 ? TCG_REG_R0 : a0;

Oops... Here is probably the regression reported by Miroslav,
I shouldn't have changed this line, simply remove the a1
assignment:

  -        a1 = args[1];
           a0 = args[0] == a1 ? TCG_REG_R0 : args[0];

>  
> -        /* a1 = args[1] # abcd */
> +        /* a1 = a1 # abcd */
>          /* a0 = rotate_left (a1, 8) # bcda */
>          tcg_out_rlw(s, RLWINM, a0, a1, 8, 0, 31);
>          /* a0 = (a0 & ~0xff000000) | ((a1 r<< 24) & 0xff000000) # dcda */
...