[PATCH][BINUTILS][AARCH64] Add support for pointer authentication B key

[Nick Clifton]

Hi Sam,

> Attached is a revised patch with the target hooks implemented and 
> target-specific definitions (pointer_auth_key etc.).
> 
> bfd/
> 
> 2018-11-20  Sam Tebbs  <sam.tebbs@arm.com>
> 
>  Â Â Â  * elf-eh-frame.c (_bfd_elf_parse_eh_frame): Add check for 'B'.
> 
> binutils/
> 
> 2018-11-20  Sam Tebbs  <sam.tebbs@arm.com>
> 
>  Â Â Â  * dwarf.c (read_cie): Add check for 'B'.
> 
> gas/
> 
> 2018-11-20  Sam Tebbs  <sam.tebbs@arm.com>
> 
>  Â Â Â  * dw2gencfi.c (struct cie_entry): Add tc_cie_entry_extras invocation.
>  Â Â Â  (alloc_fde_entry): Add tc_fde_entry_init_extra invocation.
>  Â Â Â  (output_cie): Add tc_output_cie_extra invocation.
>  Â Â Â  (select_cie_for_fde): Add tc_cie_fde_equivalent_extra and 
> tc_cie_entry_init_extra
>  Â Â Â  invocation.
>  Â Â Â  (frch_cfi_data, cfa_save_data): Move to dwgencfi.h.
>  Â Â Â  * config/tc-aarch64.c (s_aarch64_cfi_b_key_frame): Declare.
>  Â Â Â  (md_pseudo_table): Add "cfi_b_key_frame".
>  Â Â Â  * config/tc-aarch64.h (tc_fde_entry_extras, tc_cie_entry_extras,
>  Â Â Â  tc_fde_entry_init_extra, tc_output_cie_extra, 
> tc_cie_fde_equivalent_extra,
>  Â Â Â  tc_cie_entry_init_extra): Define.
>  Â Â Â  * dw2gencfi.h (struct fde_entry): Add tc_fde_entry_extras invocation.
>  Â Â Â  (pointer_auth_key): Define.
>  Â Â Â  (frch_cfi_data, cfa_save_data): Move from dwgencfi.c.
> 
> gas/doc/
> 
> 2018-11-20  Sam Tebbs  <sam.tebbs@arm.com>
> 
>  Â Â Â  * c-aarch64.texi (.cfi_b_key_frame): Add documentation.

Note - changelog entries for gas/doc actually go into gas/ChangeLog...

> gas/testsuite
> 
> 2018-11-20  Sam Tebbs  <sam.tebbs@arm.com>
> 
>  Â Â Â  * gas/aarch64/(pac_ab_key.d, pac_ab_key.s): New file.
> 

Likewise - this should be in gas/ChangeLog...

Patch approved with updates to the changelog as mentioned above.  Please apply.

Cheers
  Nick