Re: [PATCH v12 5/7] riscv: Enable multi-arg ifunc resolvers

[Florian Weimer <fweimer@redhat.com>]

* Evan Green:

> diff --git a/include/libc-symbols.h b/include/libc-symbols.h
> index e21bb599b3..4367aa6740 100644
> --- a/include/libc-symbols.h
> +++ b/include/libc-symbols.h
> @@ -667,9 +667,9 @@ for linking")
>  #endif
>  
>  /* Helper / base  macros for indirect function symbols.  */
> -#define __ifunc_resolver(type_name, name, expr, arg, init, classifier)	\
> +#define __ifunc_resolver(type_name, name, expr, init, classifier, ...)	\
>    classifier inhibit_stack_protector					\
> -  __typeof (type_name) *name##_ifunc (arg)				\
> +  __typeof (type_name) *name##_ifunc (__VA_ARGS__)			\
>    {									\
>      init ();								\
>      __typeof (type_name) *res = expr;					\
> @@ -677,13 +677,13 @@ for linking")
>    }
>  
>  #ifdef HAVE_GCC_IFUNC
> -# define __ifunc(type_name, name, expr, arg, init)			\
> +# define __ifunc_args(type_name, name, expr, init, ...)			\
>    extern __typeof (type_name) name __attribute__			\
>  			      ((ifunc (#name "_ifunc")));		\
> -  __ifunc_resolver (type_name, name, expr, arg, init, static)
> +  __ifunc_resolver (type_name, name, expr, init, static, __VA_ARGS__)
>  
> -# define __ifunc_hidden(type_name, name, expr, arg, init)	\
> -  __ifunc (type_name, name, expr, arg, init)
> +# define __ifunc_args_hidden(type_name, name, expr, init, ...)		\
> +  __ifunc_args (type_name, name, expr, init, __VA_ARGS__)
>  #else
>  /* Gcc does not support __attribute__ ((ifunc (...))).  Use the old behaviour
>     as fallback.  But keep in mind that the debug information for the ifunc
> @@ -694,18 +694,24 @@ for linking")
>     different signatures.  (Gcc support is disabled at least on a ppc64le
>     Ubuntu 14.04 system.)  */
>  
> -# define __ifunc(type_name, name, expr, arg, init)			\
> +# define __ifunc_args(type_name, name, expr, init, ...)			\
>    extern __typeof (type_name) name;					\
> -  __typeof (type_name) *name##_ifunc (arg) __asm__ (#name);		\
> -  __ifunc_resolver (type_name, name, expr, arg, init,)			\
> +  __typeof (type_name) *name##_ifunc (__VA_ARGS__) __asm__ (#name);	\
> +  __ifunc_resolver (type_name, name, expr, init, , __VA_ARGS__)		\
>   __asm__ (".type " #name ", %gnu_indirect_function");
>  
> -# define __ifunc_hidden(type_name, name, expr, arg, init)		\
> +# define __ifunc_args_hidden(type_name, name, expr, init, ...)		\
>    extern __typeof (type_name) __libc_##name;				\
> -  __ifunc (type_name, __libc_##name, expr, arg, init)			\
> +  __ifunc (type_name, __libc_##name, expr, __VA_ARGS__, init)		\
>    strong_alias (__libc_##name, name);
>  #endif /* !HAVE_GCC_IFUNC  */
>  
> +#define __ifunc(type_name, name, expr, arg, init)			\
> +  __ifunc_args (type_name, name, expr, init, arg)
> +
> +#define __ifunc_hidden(type_name, name, expr, arg, init)		\
> +  __ifunc_args_hidden (type_name, name, expr, init, arg)
> +
>  /* The following macros are used for indirect function symbols in libc.so.
>     First of all, you need to have the function prototyped somewhere,
>     say in foo.h:

The generic parts look good to me.

Reviewed-by: Florian Weimer <fweimer@redhat.com>

Thanks,
Florian