Tamar Christina <tamar.christ...@arm.com> writes:
> Hi All,
>
> GCC 15 added two new fusions CMP+CSEL and CMP+CSET.
>
> This patch enables them for cores that support based on their Software
> Optimization Guides and generically on Armv9-A. Even if a core does not
> support it there's no negative performance impact.
>
>
> Bootstrapped Regtested on aarch64-none-linux-gnu and no issues.
>
> Ok for master?
>
> Thanks,
> Tamar
>
> gcc/ChangeLog:
>
> * config/aarch64/aarch64-fusion-pairs.def (AARCH64_FUSE_NEOVERSE_BASE):
> New.
> * config/aarch64/tuning_models/cortexx925.h: Use it.
> * config/aarch64/tuning_models/generic_armv9_a.h: Use it.
> * config/aarch64/tuning_models/neoverse512tvb.h: Use it.
> * config/aarch64/tuning_models/neoversen2.h: Use it.
> * config/aarch64/tuning_models/neoversen3.h: Use it.
> * config/aarch64/tuning_models/neoversev1.h: Use it.
> * config/aarch64/tuning_models/neoversev2.h: Use it.
> * config/aarch64/tuning_models/neoversev3.h: Use it.
> * config/aarch64/tuning_models/neoversev3ae.h: Use it.
>
> ---
>
> diff --git a/gcc/config/aarch64/aarch64-fusion-pairs.def
> b/gcc/config/aarch64/aarch64-fusion-pairs.def
> index
> f8413ab0c802c28290ebcc171bfd131622cb33be..0123430d988b96b20d20376df9ae7a196031286d
> 100644
> --- a/gcc/config/aarch64/aarch64-fusion-pairs.def
> +++ b/gcc/config/aarch64/aarch64-fusion-pairs.def
> @@ -45,4 +45,8 @@ AARCH64_FUSION_PAIR ("cmp+cset", CMP_CSET)
> /* Baseline fusion settings suitable for all cores. */
> #define AARCH64_FUSE_BASE (AARCH64_FUSE_CMP_BRANCH | AARCH64_FUSE_AES_AESMC)
>
> +/* Baseline fusion settings suitable for all Neoverse cores. */
> +#define AARCH64_FUSE_NEOVERSE_BASE (AARCH64_FUSE_BASE |
> AARCH64_FUSE_CMP_CSEL \
> + | AARCH64_FUSE_CMP_CSET)
> +
> #define AARCH64_FUSE_MOVK (AARCH64_FUSE_MOV_MOVK | AARCH64_FUSE_MOVK_MOVK)
> diff --git a/gcc/config/aarch64/tuning_models/cortexx925.h
> b/gcc/config/aarch64/tuning_models/cortexx925.h
> index
> eb9b89984b0472858bc08dba924c962ec4ba53bd..b3ae1576ade1f701b775496def277230e193d20f
> 100644
> --- a/gcc/config/aarch64/tuning_models/cortexx925.h
> +++ b/gcc/config/aarch64/tuning_models/cortexx925.h
> @@ -205,7 +205,7 @@ static const struct tune_params cortexx925_tunings =
> 2 /* store_pred. */
> }, /* memmov_cost. */
> 10, /* issue_rate */
> - AARCH64_FUSE_BASE, /* fusible_ops */
> + AARCH64_FUSE_NEOVERSE_BASE, /* fusible_ops */
> "32:16", /* function_align. */
> "4", /* jump_align. */
> "32:16", /* loop_align. */
> diff --git a/gcc/config/aarch64/tuning_models/generic_armv9_a.h
> b/gcc/config/aarch64/tuning_models/generic_armv9_a.h
> index
> 48353a59939d84647c6981d6d0551af7ce9df751..e971e645dfc4b805b7f994a15a5df7803ff4dc6c
> 100644
> --- a/gcc/config/aarch64/tuning_models/generic_armv9_a.h
> +++ b/gcc/config/aarch64/tuning_models/generic_armv9_a.h
> @@ -236,7 +236,7 @@ static const struct tune_params generic_armv9_a_tunings =
> 1 /* store_pred. */
> }, /* memmov_cost. */
> 3, /* issue_rate */
> - AARCH64_FUSE_BASE, /* fusible_ops */
> + AARCH64_FUSE_NEOVERSE_BASE, /* fusible_ops */
> "32:16", /* function_align. */
> "4", /* jump_align. */
> "32:16", /* loop_align. */
Having AARCH64_FUSE_NEOVERSE_BASE seems like a good thing, but I think
we have to be careful about using it for generic tuning. generic-armv9-a
mustn't become "generic Neoverse", since it's supposed to be good for
non-Neoverse (and non-Arm) Armv9-A cores as well.
So perhaps here we should expand the macro. Alternatively, we could add
a comment saying that fusion macros for other CPUs can be added here as
well, if they are unlikely to have a negative impact on other cores.
Perhaps we should expand the macro for cortex-x925 as well.
LGTM otherwise, but let's see whether there are any other comments.
Thanks,
Richard
> diff --git a/gcc/config/aarch64/tuning_models/neoverse512tvb.h
> b/gcc/config/aarch64/tuning_models/neoverse512tvb.h
> index
> c407b89a22f1aecbfd594b493be4fbaf1f9b0437..f72505918f3aa64200aa596dbe2d7d4a3de9c08c
> 100644
> --- a/gcc/config/aarch64/tuning_models/neoverse512tvb.h
> +++ b/gcc/config/aarch64/tuning_models/neoverse512tvb.h
> @@ -143,7 +143,7 @@ static const struct tune_params neoverse512tvb_tunings =
> 1 /* store_pred. */
> }, /* memmov_cost. */
> 3, /* issue_rate */
> - AARCH64_FUSE_BASE, /* fusible_ops */
> + AARCH64_FUSE_NEOVERSE_BASE, /* fusible_ops */
> "32:16", /* function_align. */
> "4", /* jump_align. */
> "32:16", /* loop_align. */
> diff --git a/gcc/config/aarch64/tuning_models/neoversen2.h
> b/gcc/config/aarch64/tuning_models/neoversen2.h
> index
> 18199ac206c6cbfcef8695b497401b78a8f77f38..47d861232951f92bebbd09fbca8b1ff8624949fc
> 100644
> --- a/gcc/config/aarch64/tuning_models/neoversen2.h
> +++ b/gcc/config/aarch64/tuning_models/neoversen2.h
> @@ -205,7 +205,7 @@ static const struct tune_params neoversen2_tunings =
> 1 /* store_pred. */
> }, /* memmov_cost. */
> 5, /* issue_rate */
> - AARCH64_FUSE_BASE, /* fusible_ops */
> + AARCH64_FUSE_NEOVERSE_BASE, /* fusible_ops */
> "32:16", /* function_align. */
> "4", /* jump_align. */
> "32:16", /* loop_align. */
> diff --git a/gcc/config/aarch64/tuning_models/neoversen3.h
> b/gcc/config/aarch64/tuning_models/neoversen3.h
> index
> 4da85cfac0d185a5d59439f6d19d90ace0354e8f..356b5f8cc83b69e74ddac70db7a3883bc1b7a29b
> 100644
> --- a/gcc/config/aarch64/tuning_models/neoversen3.h
> +++ b/gcc/config/aarch64/tuning_models/neoversen3.h
> @@ -205,7 +205,7 @@ static const struct tune_params neoversen3_tunings =
> 2 /* store_pred. */
> }, /* memmov_cost. */
> 5, /* issue_rate */
> - AARCH64_FUSE_BASE, /* fusible_ops */
> + AARCH64_FUSE_NEOVERSE_BASE, /* fusible_ops */
> "32:16", /* function_align. */
> "4", /* jump_align. */
> "32:16", /* loop_align. */
> diff --git a/gcc/config/aarch64/tuning_models/neoversev1.h
> b/gcc/config/aarch64/tuning_models/neoversev1.h
> index
> dd9120eee48ae4fa30d589173788389c2413cdfe..9698f135a4f86a74c19cc601508ca9cb948f9298
> 100644
> --- a/gcc/config/aarch64/tuning_models/neoversev1.h
> +++ b/gcc/config/aarch64/tuning_models/neoversev1.h
> @@ -214,7 +214,7 @@ static const struct tune_params neoversev1_tunings =
> 1 /* store_pred. */
> }, /* memmov_cost. */
> 3, /* issue_rate */
> - AARCH64_FUSE_BASE, /* fusible_ops */
> + AARCH64_FUSE_NEOVERSE_BASE, /* fusible_ops */
> "32:16", /* function_align. */
> "4", /* jump_align. */
> "32:16", /* loop_align. */
> diff --git a/gcc/config/aarch64/tuning_models/neoversev2.h
> b/gcc/config/aarch64/tuning_models/neoversev2.h
> index
> 1369de73991cb9413ea3ea8fb292b7589420bab2..7e812d26556690f2e46e86fabcf5f63144370ac0
> 100644
> --- a/gcc/config/aarch64/tuning_models/neoversev2.h
> +++ b/gcc/config/aarch64/tuning_models/neoversev2.h
> @@ -218,7 +218,7 @@ static const struct tune_params neoversev2_tunings =
> 2 /* store_pred. */
> }, /* memmov_cost. */
> 5, /* issue_rate */
> - (AARCH64_FUSE_BASE | AARCH64_FUSE_CMP_CSEL | AARCH64_FUSE_CMP_CSET), /*
> fusible_ops */
> + AARCH64_FUSE_NEOVERSE_BASE, /* fusible_ops */
> "32:16", /* function_align. */
> "4", /* jump_align. */
> "32:16", /* loop_align. */
> diff --git a/gcc/config/aarch64/tuning_models/neoversev3.h
> b/gcc/config/aarch64/tuning_models/neoversev3.h
> index
> d8c82255378c81d4d2437412d41f3cbbd456f9c3..f100d484e6b2f1e63b5aedeee14bddcd29c917c9
> 100644
> --- a/gcc/config/aarch64/tuning_models/neoversev3.h
> +++ b/gcc/config/aarch64/tuning_models/neoversev3.h
> @@ -205,7 +205,7 @@ static const struct tune_params neoversev3_tunings =
> 2 /* store_pred. */
> }, /* memmov_cost. */
> 10, /* issue_rate */
> - AARCH64_FUSE_BASE, /* fusible_ops */
> + AARCH64_FUSE_NEOVERSE_BASE, /* fusible_ops */
> "32:16", /* function_align. */
> "4", /* jump_align. */
> "32:16", /* loop_align. */
> diff --git a/gcc/config/aarch64/tuning_models/neoversev3ae.h
> b/gcc/config/aarch64/tuning_models/neoversev3ae.h
> index
> 7f050501ede7108e1109ea0b5efae355380d07dc..1f59865ceadb37817def0529bdcc4b3530fef99a
> 100644
> --- a/gcc/config/aarch64/tuning_models/neoversev3ae.h
> +++ b/gcc/config/aarch64/tuning_models/neoversev3ae.h
> @@ -205,7 +205,7 @@ static const struct tune_params neoversev3ae_tunings =
> 2 /* store_pred. */
> }, /* memmov_cost. */
> 10, /* issue_rate */
> - AARCH64_FUSE_BASE, /* fusible_ops */
> + AARCH64_FUSE_NEOVERSE_BASE, /* fusible_ops */
> "32:16", /* function_align. */
> "4", /* jump_align. */
> "32:16", /* loop_align. */
