Re: plugin event for C/C++ declarations

[Richard Guenther <rguenther at suse dot de>]

On Tue, 27 Apr 2010, Brian Hackett wrote:

> On Tue, Apr 27, 2010 at 9:03 AM, Richard Guenther <rguenther@suse.de> wrote:
> > On Tue, 27 Apr 2010, Diego Novillo wrote:
> >
> >> On 4/27/10 11:54 , Richard Guenther wrote:
> >>
> >> > Yes, preferably not as a function but a global variable directly.
> >>
> >> Ugh, please no more global variables.
> >
> > ;) ?Works for me as well (it's slightly uncomfortable at -O0 ...)
> >
> > Richard.
> >
> 
> Hmm, I don't see a way for this to avoid using a global variable,
> there's no state saved for whether a plugin has been added that is not
> internal to plugin.c.  The patch below (seems to build, need to test
> regr) adds a flag_plugin_added; alternatively plugin_name_args_tab
> could be extern'ed in plugin.h but there's no reason for anything
> outside plugin.c to access this structure's internals.

The patch looks ok to me if it passes bootstrap & the plugin tests.
There are minor errors in the changelog entry,

> Brian
> 
> gcc/ChangeLog:   Brian Hackett   <bhackett1024@gmail.com>
> 
> 	* plugin.h: Change invoke_plugin_callbacks to be an inline wrapper.

        * plugin.h (invoke_plugin_callbacks): New inline function.
	(flag_plugin_added): Declare.

> Add flag_plugin_added for use by wrapper.
> 	* plugin.c: Define above flag.

	* plugin.c (flag_plugin_added): New global flag.

> 	* (add_new_plugin): Initialize above flag.

No '*' before '('

> 	* (invoke_plugin_callbacks): Rename to invoke_plugin_callbacks_full.

	(invoke_plugin_callbacks): Rename to ...
	(invoke_plugin_callbacks_full): ... this.

Thanks,
Richard.

> Index: gcc/plugin.c
> ===================================================================
> --- gcc/plugin.c	(revision 158789)
> +++ gcc/plugin.c	(working copy)
> @@ -86,6 +86,8 @@ struct callback_info
>  static struct callback_info *plugin_callbacks_init[PLUGIN_EVENT_FIRST_DYNAMIC];
>  static struct callback_info **plugin_callbacks = plugin_callbacks_init;
> 
> +/* For invoke_plugin_callbacks(), see plugin.h */
> +bool flag_plugin_added = false;
> 
>  #ifdef ENABLE_PLUGIN
>  /* Each plugin should define an initialization function with exactly
> @@ -137,6 +139,8 @@ add_new_plugin (const char* plugin_name)
>    bool name_is_short;
>    const char *pc;
> 
> +  flag_plugin_added = true;
> +
>    /* Replace short names by their full path when relevant.  */
>    name_is_short  = !IS_ABSOLUTE_PATH (plugin_name);
>    for (pc = plugin_name; name_is_short && *pc; pc++)
> @@ -483,16 +487,11 @@ unregister_callback (const char *plugin_
>    return PLUGEVT_NO_CALLBACK;
>  }
> 
> -/* Called from inside GCC.  Invoke all plug-in callbacks registered with
> -   the specified event.
> -   Return PLUGEVT_SUCCESS if at least one callback was called,
> -   PLUGEVT_NO_CALLBACK if there was no callback.
> -
> -   EVENT    - the event identifier
> -   GCC_DATA - event-specific data provided by the compiler  */
> +/* Invoke all plugin callbacks registered with the specified event,
> +   called from invoke_plugin_callbacks(). */
> 
>  int
> -invoke_plugin_callbacks (int event, void *gcc_data)
> +invoke_plugin_callbacks_full (int event, void *gcc_data)
>  {
>    int retval = PLUGEVT_SUCCESS;
> 
> Index: gcc/plugin.h
> ===================================================================
> --- gcc/plugin.h	(revision 158789)
> +++ gcc/plugin.h	(working copy)
> @@ -26,7 +26,7 @@ struct attribute_spec;
> 
>  extern void add_new_plugin (const char *);
>  extern void parse_plugin_arg_opt (const char *);
> -extern int invoke_plugin_callbacks (int, void *);
> +extern int invoke_plugin_callbacks_full (int, void *);
>  extern void initialize_plugins (void);
>  extern bool plugins_active_p (void);
>  extern void dump_active_plugins (FILE *);
> @@ -35,6 +35,27 @@ extern void print_plugins_versions (FILE
>  extern void print_plugins_help (FILE *file, const char *indent);
>  extern void finalize_plugins (void);
> 
> +/* True iff at least one plugin has been added. */
> +extern bool flag_plugin_added;
> +
> +/* Called from inside GCC.  Invoke all plugin callbacks registered with
> +   the specified event.
> +   Return PLUGEVT_SUCCESS if at least one callback was called,
> +   PLUGEVT_NO_CALLBACK if there was no callback.
> +
> +   EVENT    - the event identifier
> +   GCC_DATA - event-specific data provided by the compiler  */
> +
> +static inline int
> +invoke_plugin_callbacks (int event, void *gcc_data)
> +{
> +#ifdef ENABLE_PLUGIN
> +  if (flag_plugin_added)
> +    return invoke_plugin_callbacks_full (event, gcc_data);
> +#endif
> +  return PLUGEVT_NO_CALLBACK;
> +}
> +
>  /* In attribs.c.  */
> 
>  extern void register_attribute (const struct attribute_spec *attr);
> 
> 

-- 
Richard Guenther <rguenther@suse.de>
Novell / SUSE Labs
SUSE LINUX Products GmbH - Nuernberg - AG Nuernberg - HRB 16746 - GF: Markus Rex