Re: [PATCH v3 08/49] semihosting: Inline set_swi_errno into common_semi_cb

[Peter Maydell]

On Sat, 21 May 2022 at 01:04, Richard Henderson
<richard.henderson@linaro.org> wrote:
>
> Do not store 'err' into errno only to read it back immediately.
> Use 'ret' for the return value, not 'reg0'.
>
> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
> ---
>  semihosting/arm-compat-semi.c | 19 ++++++++++---------
>  1 file changed, 10 insertions(+), 9 deletions(-)
>
> diff --git a/semihosting/arm-compat-semi.c b/semihosting/arm-compat-semi.c
> index c6bfd4d1ba..b00ed2c6d1 100644
> --- a/semihosting/arm-compat-semi.c
> +++ b/semihosting/arm-compat-semi.c
> @@ -290,28 +290,29 @@ static target_ulong common_semi_syscall_len;
>
>  static void common_semi_cb(CPUState *cs, target_ulong ret, target_ulong err)
>  {
> -    target_ulong reg0 = common_semi_arg(cs, 0);
> -
>      if (ret == (target_ulong)-1) {
> -        errno = err;
> -        set_swi_errno(cs, -1);
> -        reg0 = ret;
> +#ifdef CONFIG_USER_ONLY
> +        TaskState *ts = cs->opaque;
> +        ts->swi_errno = err;
> +#else
> +        syscall_err = err;
> +#endif
>      } else {
>          /* Fixup syscalls that use nonstardard return conventions.  */
> +        target_ulong reg0 = common_semi_arg(cs, 0);

This should be "ret = ", right? (Otherwise I think this fails to
compile. I assume that some later patch has this fix in it.)

Otherwise
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>

thanks
-- PMM