Re: [PATCH v2 10/10] Remove reg2 section from Aarch64 SVE cores

[Simon Marchi <simark@simark.ca>]

On 2018-06-06 11:16 AM, Alan Hayward wrote:
> reg2 sections in SVE binaries will cause gdb to segfault on loading
> due to miscalculating the register size.
> 
> For now, simply remove reg2 from SVE core files. This results in
> core files without any vector/float register. Full core support
> for SVE will come in a later set of patches.
> 
> 2018-06-06  Alan Hayward  <alan.hayward@arm.com>
> 
> gdb/
> 	* aarch64-linux-tdep.c
> 	(aarch64_linux_iterate_over_regset_sections): Check for SVE.
> ---
>  gdb/aarch64-linux-tdep.c | 7 +++++--
>  1 file changed, 5 insertions(+), 2 deletions(-)
> 
> diff --git a/gdb/aarch64-linux-tdep.c b/gdb/aarch64-linux-tdep.c
> index 96dc8a1132..b05bb49ae8 100644
> --- a/gdb/aarch64-linux-tdep.c
> +++ b/gdb/aarch64-linux-tdep.c
> @@ -227,10 +227,13 @@ aarch64_linux_iterate_over_regset_sections (struct gdbarch *gdbarch,
>  					    void *cb_data,
>  					    const struct regcache *regcache)
>  {
> +  struct gdbarch_tdep *tdep = gdbarch_tdep (gdbarch);
> +
>    cb (".reg", AARCH64_LINUX_SIZEOF_GREGSET, &aarch64_linux_gregset,
>        NULL, cb_data);
> -  cb (".reg2", AARCH64_LINUX_SIZEOF_FPREGSET, &aarch64_linux_fpregset,
> -      NULL, cb_data);
> +  if (!tdep->has_sve ())
> +    cb (".reg2", AARCH64_LINUX_SIZEOF_FPREGSET, &aarch64_linux_fpregset,
> +	NULL, cb_data);
>  }
>  
>  /* Implement the "core_read_description" gdbarch method.  SVE not yet
> 

IIUC, this doesn't remove existing features?  If a program was using the neon
registers, they will still be available?

If so, this LGTM.

Simon