Re: [Qemu-devel] [PATCH v5 2/5] target/arm: handle M-profile semihosting at translate time

[Peter Maydell]

On Wed, 11 Sep 2019 at 17:50, Alex Bennée <address@hidden> wrote:
>
> We do this for other semihosting calls so we might as well do it for
> M-profile as well.
>
> Signed-off-by: Alex Bennée <address@hidden>
> Reviewed-by: Richard Henderson <address@hidden>
>
> ---
> v2
>   - update for change to gen_exception_internal_insn API
> v3
>   - update for decode tree
> v4
>   - use !IS_USER
> ---

> diff --git a/target/arm/translate.c b/target/arm/translate.c
> index 34bb280e3da..6689acc911e 100644
> --- a/target/arm/translate.c
> +++ b/target/arm/translate.c
> @@ -8424,7 +8424,13 @@ static bool trans_BKPT(DisasContext *s, arg_BKPT *a)
>      if (!ENABLE_ARCH_5) {
>          return false;
>      }
> -    gen_exception_bkpt_insn(s, syn_aa32_bkpt(a->imm, false));
> +    if (arm_dc_feature(s, ARM_FEATURE_M) &&
> +        semihosting_enabled() && !IS_USER(s) &&
> +        (a->imm == 0xab)) {
> +        gen_exception_internal_insn(s, s->base.pc_next, EXCP_SEMIHOST);
> +    } else {
> +        gen_exception_bkpt_insn(s, syn_aa32_bkpt(a->imm, false));
> +    }
>      return true;
>  }

This is still disabling semihosting for the linux-user-mode
build for M-profile, isn't it ?

thanks
-- PMM