Re: [cocci] Adding a parameter for special macro calls with SmPL

[Luca Coelho <luca@coelho.fi>]

On Sun, 2023-01-29 at 19:01 +0100, Markus Elfring wrote:
> > @macros_noargs@
> > identifier m;
> > expression e =~ "dev_priv";
> > @@
> > #define m <+...e...+>
> > 
> > @nested_macros@
> > identifier macros_noargs.m;
> > identifier nm;
> > identifier list il;
> > @@
> > #define nm(il) <+...m...+>
> > 
> > @@
> > identifier nested_macros.nm;
> > identifier list il;
> > expression e;
> > @@
> > -#define nm(il) e
> > +#define nm(dev_priv, il) e
> > 
> > @@
> > identifier nested_macros.nm;
> > identifier dev_priv, f;
> > expression e;
> > expression list il;
> > @@
> > f(...) {
> > 	...
> > (
> > 	struct drm_i915_private *dev_priv = e;
> > > 
> > 	struct drm_i915_private *dev_priv;
> > )
> 
> 
> I suggest to another look at the isomorphism “decl_init”.
> https://gitlab.inria.fr/coccinelle/coccinelle/-
> /blob/b9603af4eca7f4c771d57a3861855332e9bb1c4c/standard.iso#L465

Thanks, I took a look, the optional initialization is better, indeed.

> 
> 
> 
> > 	<+...
> > -	nm(il)
> > +	nm(dev_priv, il)
> > 	...+>
> > }
> > 
> > 
> > The idea is that all the macros that are implicitly using dev_priv,
> > will have a new argument where dev_priv is passed.
> 
> 
> Your description evolved for the desired transformation considerably.

Yes, sorry, I wanted to keep it as simple as possible, but leaving most
of the story out was indeed a problem, because it was lacking context.


> How do you think about to use the following SmPL script variant?
> 
> 
> @macros_noargs@
> identifier m;
> expression e =~ "dev_priv";
> @@
> #define m <+...e...+>
> 
> @nested_macros@
> identifier macros_noargs.m, nm;
> identifier list il;
> @@
> #define nm(il) <+...m...+>
> 
> @addition1@
> identifier nested_macros.nm;
> identifier list il;
> expression e;
> @@
> -#define nm(il) e
> +#define nm(dev_priv, il) e
> 
> @addition2@
> identifier nested_macros.nm, dev_priv, f;
> expression list el;
> @@
>  f(...)
>  {
>  ...
>  struct drm_i915_private *dev_priv;
>  <+...
>  nm(
> +   dev_priv,
>     el)
>  ...+>
>  }

This is nice, I'll change it.


> > After mangling a lot with the rules, I can see that this now works,
> 
> 
> This understanding is nice.
> 
> 
> 
> > but only if I select the vlv_dsi.c file alone, like this:
> 
> 
> This observation will probably need further explanations.
> 
> 
> 
> > Of course, I can work around this by using find and running spatch
> > individually in every file... But not ideal.
> 
> 
> The Coccinelle software should take care of corresponding source file
> searches already.

It should, but it doesn't seem to be working properly.

--
Cheers,
Luca.