Re: [Qemu-devel] [PATCH v2 5/5] target-m68k: increment/decrement with SP

[Thomas Huth]

On 13.01.2017 13:52, Laurent Vivier wrote:
> On 680x0 family only.
> 
> Address Register indirect With postincrement:
> 
> When using the stack pointer (A7) with byte size data, the register
> is incremented by two.
> 
> Address Register indirect With predecrement:
> 
> When using the stack pointer (A7) with byte size data, the register
> is decremented by two.
> 
> Signed-off-by: Laurent Vivier <address@hidden>
> ---
>  target/m68k/translate.c | 14 ++++++++++++--
>  1 file changed, 12 insertions(+), 2 deletions(-)
> 
> diff --git a/target/m68k/translate.c b/target/m68k/translate.c
> index cf5d8dd..727c189 100644
> --- a/target/m68k/translate.c
> +++ b/target/m68k/translate.c
> @@ -725,7 +725,12 @@ static TCGv gen_lea_mode(CPUM68KState *env, DisasContext 
> *s,
>          }
>          reg = get_areg(s, reg0);
>          tmp = tcg_temp_new();
> -        tcg_gen_subi_i32(tmp, reg, opsize_bytes(opsize));
> +        if (reg0 == 7 && opsize == OS_BYTE &&
> +            m68k_feature(s->env, M68K_FEATURE_M68000)) {
> +            tcg_gen_subi_i32(tmp, reg, 2);
> +        } else {
> +            tcg_gen_subi_i32(tmp, reg, opsize_bytes(opsize));
> +        }
>          return tmp;
>      case 5: /* Indirect displacement.  */
>          reg = get_areg(s, reg0);
> @@ -801,7 +806,12 @@ static TCGv gen_ea_mode(CPUM68KState *env, DisasContext 
> *s, int mode, int reg0,
>          result = gen_ldst(s, opsize, reg, val, what);
>          if (what == EA_STORE || !addrp) {
>              TCGv tmp = tcg_temp_new();
> -            tcg_gen_addi_i32(tmp, reg, opsize_bytes(opsize));
> +            if (reg0 == 7 && opsize == OS_BYTE &&
> +                m68k_feature(s->env, M68K_FEATURE_M68000)) {
> +                tcg_gen_subi_i32(tmp, reg, 2);
> +            } else {
> +                tcg_gen_addi_i32(tmp, reg, opsize_bytes(opsize));
> +            }
>              delay_set_areg(s, reg0, tmp, true);
>          }
>          return result;
> 

Reviewed-by: Thomas Huth <address@hidden>