Re: [PATCH 1/2][AArch64] Implement AAPCS64 updates for alignment attribute

[Alan Lawrence <alan.lawrence@foss.arm.com>]

On 22/01/16 17:16, Alan Lawrence wrote:
>
> On 21/01/16 17:23, Alan Lawrence wrote:
>> On 18/01/16 17:10, Eric Botcazou wrote:
>>>
>>> Could you post the list of files that differ?  How do they differ exactly?
>>
>> Hmmm. Well, I definitely had this failing to bootstrap once. I repeated that, to
>> try to identify exactly what the differences were....and it succeeded even with
>> my pre-AAPCS64-update host compiler. So, this is probably a false alarm; I'm
>> bootstrapping again, after a rebase, to make sure...
>>
>> --Alan
>
> Ok, rebased onto a more recent build, and bootstrapping with Ada posed no
> problems. Sorry for the noise.
>
> However, I had to drop the assert that TYPE_FIELDS was non-null because of some
> C++ testcases.
>
> Is this version OK for trunk?
>
> --Alan
>
> gcc/ChangeLog:
>
> 	* gcc/config/aarch64/aarch64.c (aarch64_function_arg_alignment):
> 	Rewrite, looking one level down for records and arrays.
> ---
>   gcc/config/aarch64/aarch64.c | 31 ++++++++++++++++---------------
>   1 file changed, 16 insertions(+), 15 deletions(-)
>
> diff --git a/gcc/config/aarch64/aarch64.c b/gcc/config/aarch64/aarch64.c
> index 9142ac0..b084f83 100644
> --- a/gcc/config/aarch64/aarch64.c
> +++ b/gcc/config/aarch64/aarch64.c
> @@ -1925,22 +1925,23 @@ aarch64_vfp_is_call_candidate (cumulative_args_t pcum_v, machine_mode mode,
>   static unsigned int
>   aarch64_function_arg_alignment (machine_mode mode, const_tree type)
>   {
> -  unsigned int alignment;
> +  if (!type)
> +    return GET_MODE_ALIGNMENT (mode);
> +  if (integer_zerop (TYPE_SIZE (type)))
> +    return 0;
>
> -  if (type)
> -    {
> -      if (!integer_zerop (TYPE_SIZE (type)))
> -	{
> -	  if (TYPE_MODE (type) == mode)
> -	    alignment = TYPE_ALIGN (type);
> -	  else
> -	    alignment = GET_MODE_ALIGNMENT (mode);
> -	}
> -      else
> -	alignment = 0;
> -    }
> -  else
> -    alignment = GET_MODE_ALIGNMENT (mode);
> +  gcc_assert (TYPE_MODE (type) == mode);
> +
> +  if (!AGGREGATE_TYPE_P (type))
> +    return TYPE_ALIGN (TYPE_MAIN_VARIANT (type));
> +
> +  if (TREE_CODE (type) == ARRAY_TYPE)
> +    return TYPE_ALIGN (TREE_TYPE (type));
> +
> +  unsigned int alignment = 0;
> +
> +  for (tree field = TYPE_FIELDS (type); field; field = DECL_CHAIN (field))
> +    alignment = std::max (alignment, DECL_ALIGN (field));
>
>     return alignment;
>   }
>


Ping.

If this is not appropriate for GCC6, then is it OK for Stage 1 of GCC 7?

Thanks, Alan