Hey Kyrill,
I think it should be possible, I'll have a quick look.
Cheers,
Andre
________________________________________
From: Kyrill Tkachov <kyrylo.tkac...@foss.arm.com>
Sent: Wednesday, June 20, 2018 9:32:50 AM
To: Andre Simoes Dias Vieira; gcc-patches@gcc.gnu.org
Cc: nd; James Greenhalgh; Richard Earnshaw; Marcus Shawcroft
Subject: Re: [AArch64][PATCH 1/2] Make AES unspecs commutative
Hi Andre,
On 18/06/18 10:38, Andre Simoes Dias Vieira wrote:
> Hi,
>
> This patch teaches the AArch64 backend that the AESE and AESD unspecs are
> commutative (which correspond to the vaeseq_u8 and vaesdq_u8 intrinsics).
> This improves register allocation around their corresponding instructions
> avoiding unnecessary moves.
>
> For instance, with the old patterns code such as:
>
> uint8x16_t
> test0 (uint8x16_t a, uint8x16_t b)
> {
> uint8x16_t result;
> result = vaeseq_u8 (a, b);
> result = vaeseq_u8 (result, a);
> return result;
> }
>
> would lead to suboptimal register allocation such as:
> test0:
> mov v2.16b, v0.16b
> aese v2.16b, v1.16b
> mov v1.16b, v2.16b
> aese v1.16b, v0.16b
> mov v0.16b, v1.16b
> ret
>
> whereas with the new patterns we see:
> aese v1.16b, v0.16b
> aese v0.16b, v1.16b
> ret
>
>
> Bootstrapped and tested on aarch64-none-linux-gnu.
>
> Is this OK for trunk?
>
Nice one!
Do you think we can get an equivalent patch for arm?
Thanks,
Kyrill
> Cheers,
> Andre
>
>
> gcc
> 2018-06-18 Andre Vieira <andre.simoesdiasvie...@arm.com>
>
>
> * config/aarch64/aarch64-simd.md (aarch64_crypto_aes<aes_op>v16qi):
> Make operands of the unspec commutative.
>
> gcc/testsuite
> 2018-06-18 Andre Vieira <andre.simoesdiasvie...@arm.com>
>
> * gcc/target/aarch64/aes_2.c: New test.
