Re: [PATCH 1/1] target/loongarch: LL.{W/D} need writes val to dest register after sign extension

[Richard Henderson]

On 2/1/23 17:16, Song Gao wrote:
> The Manual 2.2.7.2:
>      'The LL.{W/D} instruction retrieves a word/double-word data from
>      the specified address of the memory and writes it to the general
>      register rd after sign extension.'
>
> Signed-off-by: Song Gao <gaosong@loongson.cn>
> ---
>   target/loongarch/insn_trans/trans_atomic.c.inc | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)

The sign-extension is provided by

TRANS(ll_w, gen_ll, MO_TESL)
                    ^^^^^^^
this.

So what's the issue?


r~

> diff --git a/target/loongarch/insn_trans/trans_atomic.c.inc 
> b/target/loongarch/insn_trans/trans_atomic.c.inc
> index 6763c1c301..24fea558d6 100644
> --- a/target/loongarch/insn_trans/trans_atomic.c.inc
> +++ b/target/loongarch/insn_trans/trans_atomic.c.inc
> @@ -12,8 +12,8 @@ static bool gen_ll(DisasContext *ctx, arg_rr_i *a, MemOp mop)
>       tcg_gen_addi_tl(t0, src1, a->imm);
>       tcg_gen_qemu_ld_i64(dest, t0, ctx->mem_idx, mop);
>       tcg_gen_st_tl(t0, cpu_env, offsetof(CPULoongArchState, lladdr));
> +    gen_set_gpr(a->rd, dest, EXT_SIGN);
>       tcg_gen_st_tl(dest, cpu_env, offsetof(CPULoongArchState, llval));
> -    gen_set_gpr(a->rd, dest, EXT_NONE);
>       tcg_temp_free(t0);
>   
>       return true;