On Thu, Nov 18, 2021 at 5:55 PM apinski--- via Gcc-patches
<gcc-patches@gcc.gnu.org> wrote:
>
> From: Andrew Pinski <apin...@marvell.com>
>
> The problem here is that aarch64_expand_setmem does not change the alignment
> for strict alignment case. This is a simplified patch from what I had
> previously.
> So constraining copy_limit to the alignment of the mem in the case of strict
> align
> fixes the issue without checking to many other changes to the code.
>
> OK? Bootstrapped and tested on aarch64-linux-gnu with no regressions.
Ping?
>
> gcc/ChangeLog:
>
> * config/aarch64/aarch64.c (aarch64_expand_setmem): Constraint
> copy_limit to the alignment of the mem if STRICT_ALIGNMENT is
> true.
> ---
> gcc/config/aarch64/aarch64.c | 13 ++++++++++---
> 1 file changed, 10 insertions(+), 3 deletions(-)
>
> diff --git a/gcc/config/aarch64/aarch64.c b/gcc/config/aarch64/aarch64.c
> index 7389b5953dc..e9c2e89d8ce 100644
> --- a/gcc/config/aarch64/aarch64.c
> +++ b/gcc/config/aarch64/aarch64.c
> @@ -23744,9 +23744,16 @@ aarch64_expand_setmem (rtx *operands)
> /* Maximum amount to copy in one go. We allow 256-bit chunks based on the
> AARCH64_EXTRA_TUNE_NO_LDP_STP_QREGS tuning parameter. setmem expand
> pattern is only turned on for TARGET_SIMD. */
> - const int copy_limit = (aarch64_tune_params.extra_tuning_flags
> - & AARCH64_EXTRA_TUNE_NO_LDP_STP_QREGS)
> - ? GET_MODE_BITSIZE (TImode) : 256;
> + int copy_limit;
> +
> + if (aarch64_tune_params.extra_tuning_flags
> + & AARCH64_EXTRA_TUNE_NO_LDP_STP_QREGS)
> + copy_limit = GET_MODE_BITSIZE (TImode);
> + else
> + copy_limit = 256;
> +
> + if (STRICT_ALIGNMENT)
> + copy_limit = MIN (copy_limit, (int)MEM_ALIGN (dst));
>
> while (n > 0)
> {
> --
> 2.17.1
>
