Re: [PATCH v6 55/61] target/riscv: integer extract instruction

[Richard Henderson]

On 3/17/20 8:06 AM, LIU Zhiwei wrote:
> +/* Integer Extract Instruction */
> +static void extract_element(TCGv dest, TCGv_ptr base,
> +                            int ofs, int sew)
> +{
> +    switch (sew) {
> +    case MO_8:
> +        tcg_gen_ld8u_tl(dest, base, ofs);
> +        break;
> +    case MO_16:
> +        tcg_gen_ld16u_tl(dest, base, ofs);
> +        break;
> +    default:
> +        tcg_gen_ld32u_tl(dest, base, ofs);
> +        break;
> +#if TARGET_LONG_BITS == 64
> +    case MO_64:
> +        tcg_gen_ld_i64(dest, base, ofs);
> +        break;
> +#endif
> +    }
> +}

I just remembered that this doesn't handle HOST_WORDS_BIGENDIAN properly -- the
MO_64 case for TARGET_LONG_BITS == 32.

Because we computed the offset for MO_64, not MO_32, we need

    case MO_64:
        if (TARGET_LONG_BITS == 64) {
            tcg_gen_ld_i64(dest, base, ofs);
            break;
        }
#ifdef HOST_WORDS_BIGENDIAN
        ofs += 4;
#endif
        /* fall through */
    case MO_32:
        tcg_gen_ld32u_tl(dest, base, ofs);
        break;
    default:
        g_assert_not_reached();


r~