Re: [RFA] Displaced stepping just enable in non-stop mode

Pedro Alves
2008-10-09T14:50:02Z

Hi,

Thanks for doing this.

On Wednesday 08 October 2008 07:10:43, teawater wrote:

> -int can_use_displaced_stepping = 1;
> +const char can_use_displaced_stepping_auto[] = "auto";
> +const char can_use_displaced_stepping_on[] = "on";
> +const char can_use_displaced_stepping_off[] = "off";
> +const char *can_use_displaced_stepping_enum[] =
> +{
> +  can_use_displaced_stepping_auto,
> +  can_use_displaced_stepping_on,
> +  can_use_displaced_stepping_off,
> +  NULL,
> +};
> +const char *can_use_displaced_stepping = can_use_displaced_stepping_auto;

Could you make these static while you're at it, please? It was just missed
in the old boolean setting.

>  static void
>  show_can_use_displaced_stepping (struct ui_file *file, int from_tty,
>                                  struct cmd_list_element *c,
> @@ -567,12 +579,16 @@ Debugger's willingness to use displaced
>  "breakpoints is %s.\n"), value);

Could you update this function to show what effect the auto setting
is currently having? See breakpoint.c:show_always_inserted_mode for
an example.

>  }
>
> -/* Return non-zero if displaced stepping is enabled, and can be used
> +/* Return non-zero if displaced stepping is auto, and can be used
> +   with GDBARCH, and in non-stop mode.
> +   Return non-zero if displaced stepping is on, and can be used
>     with GDBARCH.  */
>  static int
>  use_displaced_stepping (struct gdbarch *gdbarch)
>  {
> -  return (can_use_displaced_stepping
> +  return (((can_use_displaced_stepping == can_use_displaced_stepping_auto
> +           && non_stop)
> +          || can_use_displaced_stepping == can_use_displaced_stepping_on)
>           && gdbarch_displaced_step_copy_insn_p (gdbarch));
>  }
>
> @@ -4857,11 +4873,14 @@ function is skipped and the step command
>                            show_step_stop_if_no_debug,
>                            &setlist, &showlist);
>
> -  add_setshow_boolean_cmd ("can-use-displaced-stepping", class_maintenance,
> +  add_setshow_enum_cmd ("can-use-displaced-stepping", class_maintenance,
> +                          can_use_displaced_stepping_enum,
>                            &can_use_displaced_stepping, _("\
>  Set debugger's willingness to use displaced stepping."), _("\
>  Show debugger's willingness to use displaced stepping."), _("\
> -If zero, gdb will not use displaced stepping to step over\n\
> +If auto, gdb will auto use displaced stepping if it need (in non-stop mode).\n\
> +If on, gdb will use displaced stepping if such is supported by the target.\n\
> +If off, gdb will not use displaced stepping to step over\n\
>  breakpoints, even if such is supported by the target."),

This also needs to be updated in the manual. I'd suggest borrowing the text
from breakpoint.c's "always-inserted" command description to make it a
bit more descriptive, and mention which mode is the default. Should mostly
be a matter of copy-paste, I think.

--
Pedro Alves