[PATCH] elf: Remove the GET_ADDR_ARGS and related macros from the TLS code

[Florian Weimer]

* Florian Weimer:

> This was used to manage an IA-64 ABI divergence is no longere needed
> after the IA-64 removal.
>
> (It should be possible to encode all the required information in
> one machine word, so the pointer indirection is really unnecessary.
> Technically, none of this is part of the ABI, so perhaps it's
> possible to do this retroactively.  See bug 27404.)
>
> Tested on x86_64-linux-gnu.  Built with build-many-glibcs.py.
>
> ---
>  elf/dl-tls.c            | 55 +++++++++++++++++--------------------------------
>  sysdeps/x86_64/dl-tls.c |  8 +++----
>  2 files changed, 23 insertions(+), 40 deletions(-)
>
> diff --git a/elf/dl-tls.c b/elf/dl-tls.c
> index 3d529b722c..4df83b9bb2 100644
> --- a/elf/dl-tls.c
> +++ b/elf/dl-tls.c
> @@ -695,23 +695,6 @@ rtld_hidden_def (_dl_deallocate_tls)
>  
>  
>  #ifdef SHARED
> -/* The __tls_get_addr function has two basic forms which differ in the
> -   arguments.  The IA-64 form takes two parameters, the module ID and
> -   offset.  The form used, among others, on IA-32 takes a reference to
> -   a special structure which contain the same information.  The second
> -   form seems to be more often used (in the moment) so we default to
> -   it.  Users of the IA-64 form have to provide adequate definitions
> -   of the following macros.  */
> -# ifndef GET_ADDR_ARGS
> -#  define GET_ADDR_ARGS tls_index *ti
> -#  define GET_ADDR_PARAM ti
> -# endif
> -# ifndef GET_ADDR_MODULE
> -#  define GET_ADDR_MODULE ti->ti_module
> -# endif
> -# ifndef GET_ADDR_OFFSET
> -#  define GET_ADDR_OFFSET ti->ti_offset
> -# endif

So it turns out this comment was very misleading.  GET_ADDR_ARGS is
indeed specific to IA-64, but GET_ADDR_OFFSET was used on various other
architectures.  This breaks TLS on s390x, among other things.

I'm working on a fix.

Thanks,
Florian