>> OK.
Thanks. Committed.
>> Note load/store-lanes is specifically pre-empting SLP if all
>> loads/stores of a SLP intance can support that. Not sure if this
>> heuristic is good for load/store lanes with high stride?
Yeah, I understand your concern.
Emmmmm, I am sure too.
But RVV ISA define lanes load/store from 2 to 8 and LLVM already supported.
I think we can fully support them, then let RISC-V COST model decide it whether
it is profitable or not.
Also, I found RVV can vectorize a TSVC case with stride = 5
lane_load/lane_store:
tsvc-s353.c:
-/* { dg-final { scan-tree-dump "vectorized 1 loops" "vect" { xfail *-*-* } } }
*/
+/* { dg-final { scan-tree-dump "vectorized 1 loops" "vect" { xfail { ! riscv_v
} } } } */
https://gcc.gnu.org/pipermail/gcc-patches/2023-October/632213.html
So, I think overall it is beneficial we support high stride lane load/store
which can help us vectorize more cases.
juzhe.zh...@rivai.ai
From: Richard Biener
Date: 2023-10-09 20:41
To: Juzhe-Zhong
CC: gcc-patches; jeffreyalaw
Subject: Re: [PATCH] RISC-V Regression test: Fix FAIL of fast-math-slp-38.c for
RVV
On Mon, 9 Oct 2023, Juzhe-Zhong wrote:
> Reference: https://godbolt.org/z/G9jzf5Grh
>
> RVV is able to vectorize this case using SLP. However, with
> -fno-vect-cost-model, RVV vectorize it by vec_load_lanes with stride 6.
OK. Note load/store-lanes is specifically pre-empting SLP if all
loads/stores of a SLP intance can support that. Not sure if this
heuristic is good for load/store lanes with high stride?
> gcc/testsuite/ChangeLog:
>
> * gcc.dg/vect/fast-math-slp-38.c: Add ! vect_strided6.
>
> ---
> gcc/testsuite/gcc.dg/vect/fast-math-slp-38.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/gcc/testsuite/gcc.dg/vect/fast-math-slp-38.c
> b/gcc/testsuite/gcc.dg/vect/fast-math-slp-38.c
> index 7c7acd5bab6..96751faae7f 100644
> --- a/gcc/testsuite/gcc.dg/vect/fast-math-slp-38.c
> +++ b/gcc/testsuite/gcc.dg/vect/fast-math-slp-38.c
> @@ -18,4 +18,4 @@ foo (void)
> }
>
> /* { dg-final { scan-tree-dump-times "vectorized 1 loops" 1 "vect" } } */
> -/* { dg-final { scan-tree-dump-times "vectorizing stmts using SLP" 1 "vect"
> } } */
> +/* { dg-final { scan-tree-dump-times "vectorizing stmts using SLP" 1 "vect"
> { target { ! vect_strided6 } } } } */
>
--
Richard Biener <rguent...@suse.de>
SUSE Software Solutions Germany GmbH,
Frankenstrasse 146, 90461 Nuernberg, Germany;
GF: Ivo Totev, Andrew McDonald, Werner Knoblich; (HRB 36809, AG Nuernberg)
