This is the mail archive of the gcc-patches@gcc.gnu.org mailing list for the GCC project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

Re: [AArch64][PATCH 1/2] Fix addressing printing of LDP/STP


On 17/07/18 15:52, James Greenhalgh wrote:
> On Mon, Jun 25, 2018 at 03:48:13AM -0500, Andre Simoes Dias Vieira wrote:
>> On 18/06/18 09:08, Andre Simoes Dias Vieira wrote:
>>> Hi Richard,
>>>
>>> Sorry for the delay I have been on holidays.  I had a look and I think you are right.  With these changes Umq and Uml seem to have the same functionality though, so I would suggest using only one.  Maybe use a different name for both, removing both Umq and Uml in favour of Umn, where the n indicates it narrows the addressing mode.  How does that sound to you?
>>>
>>> I also had a look at Ump, but that one is used in the parallel pattern for STP/LDP which does not use this "narrowing". So we should leave that one as is.
>>>
>>> Cheers,
>>> Andre
>>>
>>> ________________________________________
>>> From: Richard Sandiford <richard.sandiford@arm.com>
>>> Sent: Thursday, June 14, 2018 12:28:16 PM
>>> To: Andre Simoes Dias Vieira
>>> Cc: gcc-patches@gcc.gnu.org; nd
>>> Subject: Re: [AArch64][PATCH 1/2] Fix addressing printing of LDP/STP
>>>
>>> Andre Simoes Dias Vieira <Andre.SimoesDiasVieira@arm.com> writes:
>>>> @@ -5716,10 +5717,17 @@ aarch64_classify_address (struct aarch64_address_info *info,
>>>>    unsigned int vec_flags = aarch64_classify_vector_mode (mode);
>>>>    bool advsimd_struct_p = (vec_flags == (VEC_ADVSIMD | VEC_STRUCT));
>>>>    bool load_store_pair_p = (type == ADDR_QUERY_LDP_STP
>>>> +                         || type == ADDR_QUERY_LDP_STP_N
>>>>                           || mode == TImode
>>>>                           || mode == TFmode
>>>>                           || (BYTES_BIG_ENDIAN && advsimd_struct_p));
>>>>
>>>> +  /* If we are dealing with ADDR_QUERY_LDP_STP_N that means the incoming mode
>>>> +     corresponds to the actual size of the memory being loaded/stored and the
>>>> +     mode of the corresponding addressing mode is half of that.  */
>>>> +  if (type == ADDR_QUERY_LDP_STP_N && known_eq (GET_MODE_SIZE (mode), 16))
>>>> +    mode = DFmode;
>>>> +
>>>>    bool allow_reg_index_p = (!load_store_pair_p
>>>>                           && (known_lt (GET_MODE_SIZE (mode), 16)
>>>>                               || vec_flags == VEC_ADVSIMD
>>>
>>> I don't know whether it matters in practice, but that description also
>>> applies to Umq, not just Uml.  It might be worth changing it too so
>>> that things stay consistent.
>>>
>>> Thanks,
>>> Richard
>>>
>> Hi all,
>>
>> This is a reworked patched, replacing Umq and Uml with Umn now.
>>
>> Bootstrapped and tested on aarch64-none-linux-gnu.
>>
>> Is this OK for trunk?
> 
> OK. Does this also need backporting to 8?

It doesn't __need__ to, as the failure this fixes has not been observed
on gcc-8, I assume that is because of our restrictive  LDP/STP
generation (see patch 2/2 of this series).  Though it wouldn't hurt
either I think.
> 
> Thanks,
> James
> 
>>
>> gcc
>> 2018-06-25  Andre Vieira  <andre.simoesdiasvieira@arm.com>
>>
>>         * config/aarch64/aarch64-simd.md (aarch64_simd_mov<VQ:mode>):
>> Replace
>>         Umq with Umn.
>>         (store_pair_lanes<mode>): Likewise.
>>         * config/aarch64/aarch64-protos.h (aarch64_addr_query_type): Add new
>>         enum value 'ADDR_QUERY_LDP_STP_N'.
>>         * config/aarch64/aarch64.c (aarch64_addr_query_type): Likewise.
>>         (aarch64_print_address_internal): Add declaration.
>>         (aarch64_print_ldpstp_address): Remove.
>>         (aarch64_classify_address): Adapt mode for 'ADDR_QUERY_LDP_STP_N'.
>>         (aarch64_print_operand): Change printing of 'y'.
>>         * config/aarch64/predicates.md (aarch64_mem_pair_lanes_operand): Use
>>         new enum value 'ADDR_QUERY_LDP_STP_N', don't hardcode mode and use
>>         'true' rather than '1'.
>>         * gcc/config/aarch64/constraints.md (Uml): Likewise.
>>         (Uml): Rename to Umn.
>>         (Umq): Remove.
> 


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]