[Cocci] Ignoring all code in #ifdef blocks

[Cocci] Ignoring all code in #ifdef blocks

[Andrew F. Davis]

Hello all,

I am working on a cocci script to remove unneeded code and I have
hopefully a simple question. My script attempts to remove a macro's use,
but only when a relevant struct definition is *not* blocked off by #if
and/or #ifdef CONFIG_OF. I think I would just like to have cocci ignore
all code in-between any blocks but I cannot seem to get it to work. I
have tried --no-includes and --undefined CONFIG_OF, but it still removes
the target macro, even when the struct is in an ifdef block. Example:

static const struct of_device_id gpio_ids[];

static int somefunction()
{
	const struct of_device_id *match;

	match = of_match_device(of_match_ptr(davinci_gpio_ids));
}

#if IS_ENABLED(CONFIG_OF)
static const struct of_device_id gpio_ids[] = {
	{ .compatible = "gpio", },
	{ /* sentinel */ },
};
MODULE_DEVICE_TABLE(of, gpio_ids);
#endif

static struct platform_driver gpio_driver = {
	.probe		= gpio_probe,
	.driver		= {
		.name		= "gpio",
		.of_match_table	= of_match_ptr(gpio_ids),
	},
};

None of the of_match_ptr should be removed in the above file, but if the
#if/endif were remove all should be removed, but I'm not sure how to
match for the ifdef?

Here is my script so far:

@s@
identifier arr;
@@
(
  struct of_device_id arr[] = {
  	...
  };
)

@depends on s@
identifier s.arr;
@@
(
- of_match_ptr(arr)
+ arr
)

Thanks,
Andrew

[Cocci] Ignoring all code in #ifdef blocks

[Julia Lawall]

On Mon, 9 May 2016, Andrew F. Davis wrote:

> Hello all,
> 
> I am working on a cocci script to remove unneeded code and I have
> hopefully a simple question. My script attempts to remove a macro's use,
> but only when a relevant struct definition is *not* blocked off by #if
> and/or #ifdef CONFIG_OF. I think I would just like to have cocci ignore
> all code in-between any blocks but I cannot seem to get it to work. I
> have tried --no-includes and --undefined CONFIG_OF, but it still removes
> the target macro, even when the struct is in an ifdef block. Example:
> 
> static const struct of_device_id gpio_ids[];
> 
> static int somefunction()
> {
> 	const struct of_device_id *match;
> 
> 	match = of_match_device(of_match_ptr(davinci_gpio_ids));
> }
> 
> #if IS_ENABLED(CONFIG_OF)
> static const struct of_device_id gpio_ids[] = {
> 	{ .compatible = "gpio", },
> 	{ /* sentinel */ },
> };
> MODULE_DEVICE_TABLE(of, gpio_ids);
> #endif
> 
> static struct platform_driver gpio_driver = {
> 	.probe		= gpio_probe,
> 	.driver		= {
> 		.name		= "gpio",
> 		.of_match_table	= of_match_ptr(gpio_ids),
> 	},
> };
> 
> None of the of_match_ptr should be removed in the above file, but if the
> #if/endif were remove all should be removed, but I'm not sure how to
> match for the ifdef?

I'm not very familiar with the --undefined option, but it seems that it 
only works with #ifdef and #ifndef, not #if.

There is no way to match against a #if or #ifdef.  Here the problem is 
particularly complex, because the #if surround multiple top-level code 
units, and Coccinelle matches the top-level code units one at a time.

julia

> 
> Here is my script so far:
> 
> @s@
> identifier arr;
> @@
> (
>   struct of_device_id arr[] = {
>   	...
>   };
> )
> 
> @depends on s@
> identifier s.arr;
> @@
> (
> - of_match_ptr(arr)
> + arr
> )
> 
> Thanks,
> Andrew
> _______________________________________________
> Cocci mailing list
> Cocci at systeme.lip6.fr
> https://systeme.lip6.fr/mailman/listinfo/cocci
> 

[Cocci] Ignoring all code in #ifdef blocks

[Iago Abal]

Hi,

Indeed, --undefined only works for #ifdef and #ifndef. In any case,
Coccinelle doesn't know the definition of "IS_ENABLED". It would have to
support undefine'ing an expression, as in --undefined
"IS_ENABLED(CONFIG_OF)". Undefine'ing happens during lexing, when #if
expressions are still raw strings, so perhaps one could support
undefine'ing regular expressions over those strings.


Iago

On Mon, May 9, 2016 at 10:01 PM, Julia Lawall <julia.lawall@lip6.fr> wrote:

>
>
> On Mon, 9 May 2016, Andrew F. Davis wrote:
>
> > Hello all,
> >
> > I am working on a cocci script to remove unneeded code and I have
> > hopefully a simple question. My script attempts to remove a macro's use,
> > but only when a relevant struct definition is *not* blocked off by #if
> > and/or #ifdef CONFIG_OF. I think I would just like to have cocci ignore
> > all code in-between any blocks but I cannot seem to get it to work. I
> > have tried --no-includes and --undefined CONFIG_OF, but it still removes
> > the target macro, even when the struct is in an ifdef block. Example:
> >
> > static const struct of_device_id gpio_ids[];
> >
> > static int somefunction()
> > {
> >       const struct of_device_id *match;
> >
> >       match = of_match_device(of_match_ptr(davinci_gpio_ids));
> > }
> >
> > #if IS_ENABLED(CONFIG_OF)
> > static const struct of_device_id gpio_ids[] = {
> >       { .compatible = "gpio", },
> >       { /* sentinel */ },
> > };
> > MODULE_DEVICE_TABLE(of, gpio_ids);
> > #endif
> >
> > static struct platform_driver gpio_driver = {
> >       .probe          = gpio_probe,
> >       .driver         = {
> >               .name           = "gpio",
> >               .of_match_table = of_match_ptr(gpio_ids),
> >       },
> > };
> >
> > None of the of_match_ptr should be removed in the above file, but if the
> > #if/endif were remove all should be removed, but I'm not sure how to
> > match for the ifdef?
>
> I'm not very familiar with the --undefined option, but it seems that it
> only works with #ifdef and #ifndef, not #if.
>
> There is no way to match against a #if or #ifdef.  Here the problem is
> particularly complex, because the #if surround multiple top-level code
> units, and Coccinelle matches the top-level code units one at a time.
>
> julia
>
> >
> > Here is my script so far:
> >
> > @s@
> > identifier arr;
> > @@
> > (
> >   struct of_device_id arr[] = {
> >       ...
> >   };
> > )
> >
> > @depends on s@
> > identifier s.arr;
> > @@
> > (
> > - of_match_ptr(arr)
> > + arr
> > )
> >
> > Thanks,
> > Andrew
> > _______________________________________________
> > Cocci mailing list
> > Cocci at systeme.lip6.fr
> > https://systeme.lip6.fr/mailman/listinfo/cocci
> >
>
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