[PATCH 08/15] nios2: Use Linux kABI for syscall return

[Vineet Gupta]

On 2/10/20 11:20 AM, Adhemerval Zanella wrote:
> It changes the nios INTERNAL_SYSCALL_RAW macro to return a negative
> value instead of 'r2' register value on 'err' macro argument.
> 
> The macro INTERNAL_SYSCALL_DECL is no longer required, and the
> INTERNAL_SYSCALL_ERROR_P follows the other Linux kABIS.
> 
> Checked with a build against nios2-linux-gnu.
> ---
>  sysdeps/unix/sysv/linux/nios2/sysdep.h | 10 +++++-----
>  1 file changed, 5 insertions(+), 5 deletions(-)
> 
> diff --git a/sysdeps/unix/sysv/linux/nios2/sysdep.h b/sysdeps/unix/sysv/linux/nios2/sysdep.h
> index b02730bd23..eab888df32 100644
> --- a/sysdeps/unix/sysv/linux/nios2/sysdep.h
> +++ b/sysdeps/unix/sysv/linux/nios2/sysdep.h
> @@ -157,13 +157,14 @@
>       (int) result_var; })
>  
>  #undef INTERNAL_SYSCALL_DECL
> -#define INTERNAL_SYSCALL_DECL(err) unsigned int err __attribute__((unused))
> +#define INTERNAL_SYSCALL_DECL(err) do { } while (0)
>  
>  #undef INTERNAL_SYSCALL_ERROR_P
> -#define INTERNAL_SYSCALL_ERROR_P(val, err) ((void) (val), (unsigned int) (err))
> +#define INTERNAL_SYSCALL_ERROR_P(val, err) \
> +  ((unsigned long) (val) >= (unsigned long) -4095)
>  
>  #undef INTERNAL_SYSCALL_ERRNO
> -#define INTERNAL_SYSCALL_ERRNO(val, err)   ((void) (err), val)
> +#define INTERNAL_SYSCALL_ERRNO(val, err)     (-(val))
>  
>  #undef INTERNAL_SYSCALL_RAW
>  #define INTERNAL_SYSCALL_RAW(name, err, nr, args...)            \
> @@ -180,8 +181,7 @@
>                       : "+r" (_r2), "=r" (_err)                  \
>                       : ASM_ARGS_##nr				\
>                       : __SYSCALL_CLOBBERS);                     \
> -       _sys_result = _r2;                                       \
> -       err = _err;                                              \
> +       _sys_result = _err != 0 ? -_r2 : -_r2;                   \

Is there a typo here ? both cases seem to be -ve

>       }                                                          \
>       (int) _sys_result; })
>  
>