On Fri, Jul 25, 2025 at 5:14 AM Jennifer Schmitz <jschm...@nvidia.com> wrote:
>
> This patch adds a new tuning model for the NVIDIA Olympus core.
> The values used here are based on the Software Optimization Guide
> that will be published imminently.
>
> Bootstrapped and tested on aarch64-linux-gnu, no regression.
>
> OK for trunk?
Ok from the trunk.
> OK to backport to GCC 15?
I think this should wait until after the release of GCC 15.2.0. RC1
comes out at the end of this coming week.
Thanks,
Andrew
>
> Signed-off-by: Jennifer Schmitz <jschm...@nvidia.com>
> Co-Authored-By: Dhruv Chawla <dhr...@nvidia.com>
>
> gcc/ChangeLog:
>
> * config/aarch64/aarch64-cores.def (olympus): Use olympus tuning
> model.
> * config/aarch64/aarch64.cc: Include olympus.h.
> * config/aarch64/tuning_models/olympus.h: New file.
> ---
> gcc/config/aarch64/aarch64-cores.def | 2 +-
> gcc/config/aarch64/aarch64.cc | 1 +
> gcc/config/aarch64/tuning_models/olympus.h | 210 +++++++++++++++++++++
> 3 files changed, 212 insertions(+), 1 deletion(-)
> create mode 100644 gcc/config/aarch64/tuning_models/olympus.h
>
> diff --git a/gcc/config/aarch64/aarch64-cores.def
> b/gcc/config/aarch64/aarch64-cores.def
> index 8040409d283..6f11cc0983a 100644
> --- a/gcc/config/aarch64/aarch64-cores.def
> +++ b/gcc/config/aarch64/aarch64-cores.def
> @@ -224,7 +224,7 @@ AARCH64_CORE("neoverse-v3ae", neoversev3ae, cortexa57,
> V9_2A, (SVE2_BITPERM, RNG
> AARCH64_CORE("demeter", demeter, cortexa57, V9A, (I8MM, BF16, SVE2_BITPERM,
> RNG, MEMTAG, PROFILE), neoversev2, 0x41, 0xd4f, -1)
>
> /* NVIDIA ('N') cores. */
> -AARCH64_CORE("olympus", olympus, cortexa57, V9_2A, (SVE2_BITPERM, RNG, LS64,
> MEMTAG, PROFILE, FAMINMAX, FP8FMA, FP8DOT2, FP8DOT4, LUT, SVE2_AES,
> SVE2_SHA3, SVE2_SM4), neoversev3, 0x4e, 0x10, -1)
> +AARCH64_CORE("olympus", olympus, cortexa57, V9_2A, (SVE2_BITPERM, RNG, LS64,
> MEMTAG, PROFILE, FAMINMAX, FP8FMA, FP8DOT2, FP8DOT4, LUT, SVE2_AES,
> SVE2_SHA3, SVE2_SM4), olympus, 0x4e, 0x10, -1)
>
> /* Armv9-A big.LITTLE processors. */
> AARCH64_CORE("gb10", gb10, cortexa57, V9_2A, (SVE2_BITPERM, SVE2_AES,
> SVE2_SHA3, SVE2_SM4, MEMTAG, PROFILE), cortexx925, 0x41, AARCH64_BIG_LITTLE
> (0xd85, 0xd87), -1)
> diff --git a/gcc/config/aarch64/aarch64.cc b/gcc/config/aarch64/aarch64.cc
> index 0485f695941..58fef7198ba 100644
> --- a/gcc/config/aarch64/aarch64.cc
> +++ b/gcc/config/aarch64/aarch64.cc
> @@ -429,6 +429,7 @@ static const struct aarch64_flag_desc
> aarch64_tuning_flags[] =
> #include "tuning_models/neoversev2.h"
> #include "tuning_models/neoversev3.h"
> #include "tuning_models/neoversev3ae.h"
> +#include "tuning_models/olympus.h"
> #include "tuning_models/a64fx.h"
> #include "tuning_models/fujitsu_monaka.h"
>
> diff --git a/gcc/config/aarch64/tuning_models/olympus.h
> b/gcc/config/aarch64/tuning_models/olympus.h
> new file mode 100644
> index 00000000000..268789db019
> --- /dev/null
> +++ b/gcc/config/aarch64/tuning_models/olympus.h
> @@ -0,0 +1,210 @@
> +/* Tuning model description for the NVIDIA Olympus core.
> + Copyright The GNU Toolchain Authors.
> +
> + This file is part of GCC.
> +
> + GCC is free software; you can redistribute it and/or modify it
> + under the terms of the GNU General Public License as published by
> + the Free Software Foundation; either version 3, or (at your option)
> + any later version.
> +
> + GCC is distributed in the hope that it will be useful, but
> + WITHOUT ANY WARRANTY; without even the implied warranty of
> + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
> + General Public License for more details.
> +
> + You should have received a copy of the GNU General Public License
> + along with GCC; see the file COPYING3. If not see
> + <http://www.gnu.org/licenses/>. */
> +
> +#ifndef GCC_AARCH64_H_OLYMPUS
> +#define GCC_AARCH64_H_OLYMPUS
> +
> +#include "generic.h"
> +
> +static struct cpu_regmove_cost olympus_regmove_cost =
> +{
> + 1, /* GP2GP */
> + /* Spilling to int<->fp instead of memory is recommended so set
> + realistic costs compared to memmov_cost. */
> + 3, /* GP2FP */
> + 3, /* FP2GP */
> + 2 /* FP2FP */
> +};
> +
> +static advsimd_vec_cost olympus_advsimd_vector_cost =
> +{
> + 2, /* int_stmt_cost */
> + 2, /* fp_stmt_cost */
> + 2, /* ld2_st2_permute_cost */
> + 2, /* ld3_st3_permute_cost */
> + 3, /* ld4_st4_permute_cost */
> + 2, /* permute_cost */
> + 5, /* reduc_i8_cost */
> + 3, /* reduc_i16_cost */
> + 3, /* reduc_i32_cost */
> + 2, /* reduc_i64_cost */
> + 4, /* reduc_f16_cost */
> + 4, /* reduc_f32_cost */
> + 4, /* reduc_f64_cost */
> + 2, /* store_elt_extra_cost */
> + 8, /* vec_to_scalar_cost */
> + 4, /* scalar_to_vec_cost */
> + 6, /* align_load_cost */
> + 6, /* unalign_load_cost */
> + 1, /* unalign_store_cost */
> + 1 /* store_cost */
> +};
> +
> +static sve_vec_cost olympus_sve_vector_cost =
> +{
> + {
> + 2, /* int_stmt_cost */
> + 2, /* fp_stmt_cost */
> + 2, /* ld2_st2_permute_cost */
> + 3, /* ld3_st3_permute_cost */
> + 3, /* ld4_st4_permute_cost */
> + 2, /* permute_cost */
> + 9, /* reduc_i8_cost */
> + 8, /* reduc_i16_cost */
> + 6, /* reduc_i32_cost */
> + 2, /* reduc_i64_cost */
> + 8, /* reduc_f16_cost */
> + 6, /* reduc_f32_cost */
> + 4, /* reduc_f64_cost */
> + 2, /* store_elt_extra_cost */
> + 8, /* vec_to_scalar_cost */
> + 4, /* scalar_to_vec_cost */
> + 4, /* align_load_cost */
> + 6, /* unalign_load_cost */
> + 1, /* unalign_store_cost */
> + 1 /* store_cost */
> + },
> + 3, /* clast_cost */
> + 10, /* fadda_f16_cost */
> + 6, /* fadda_f32_cost */
> + 4, /* fadda_f64_cost */
> + 14, /* gather_load_x32_cost */
> + 12, /* gather_load_x64_cost */
> + 42, /* gather_load_x32_init_cost */
> + 24, /* gather_load_x64_init_cost */
> + 1 /* scatter_store_elt_cost */
> +};
> +
> +static aarch64_scalar_vec_issue_info olympus_scalar_issue_info =
> +{
> + 4, /* loads_stores_per_cycle */
> + 2, /* stores_per_cycle */
> + 8, /* general_ops_per_cycle */
> + 0, /* fp_simd_load_general_ops */
> + 1 /* fp_simd_store_general_ops */
> +};
> +
> +static aarch64_advsimd_vec_issue_info olympus_advsimd_issue_info =
> +{
> + {
> + 3, /* loads_stores_per_cycle */
> + 2, /* stores_per_cycle */
> + 6, /* general_ops_per_cycle */
> + 0, /* fp_simd_load_general_ops */
> + 1 /* fp_simd_store_general_ops */
> + },
> + 2, /* ld2_st2_general_ops */
> + 2, /* ld3_st3_general_ops */
> + 3 /* ld4_st4_general_ops */
> +};
> +
> +static aarch64_sve_vec_issue_info olympus_sve_issue_info =
> +{
> + {
> + {
> + 3, /* loads_stores_per_cycle */
> + 2, /* stores_per_cycle */
> + 6, /* general_ops_per_cycle */
> + 0, /* fp_simd_load_general_ops */
> + 1 /* fp_simd_store_general_ops */
> + },
> + 2, /* ld2_st2_general_ops */
> + 2, /* ld3_st3_general_ops */
> + 3 /* ld4_st4_general_ops */
> + },
> + 2, /* pred_ops_per_cycle */
> + 1, /* while_pred_ops */
> + 0, /* int_cmp_pred_ops */
> + 0, /* fp_cmp_pred_ops */
> + 1, /* gather_scatter_pair_general_ops */
> + 1 /* gather_scatter_pair_pred_ops */
> +};
> +
> +static aarch64_vec_issue_info olympus_vec_issue_info =
> +{
> + &olympus_scalar_issue_info,
> + &olympus_advsimd_issue_info,
> + &olympus_sve_issue_info
> +};
> +
> +/* Olympus costs for vector insn classes. */
> +static struct cpu_vector_cost olympus_vector_cost =
> +{
> + 1, /* scalar_int_stmt_cost */
> + 2, /* scalar_fp_stmt_cost */
> + 4, /* scalar_load_cost */
> + 1, /* scalar_store_cost */
> + 1, /* cond_taken_branch_cost */
> + 1, /* cond_not_taken_branch_cost */
> + &olympus_advsimd_vector_cost, /* advsimd */
> + &olympus_sve_vector_cost, /* sve */
> + &olympus_vec_issue_info /* issue_info */
> +};
> +
> +/* Olympus prefetch settings (which disable prefetch). */
> +static cpu_prefetch_tune olympus_prefetch_tune =
> +{
> + 0, /* num_slots */
> + -1, /* l1_cache_size */
> + 64, /* l1_cache_line_size */
> + -1, /* l2_cache_size */
> + true, /* prefetch_dynamic_strides */
> + -1, /* minimum_stride */
> + -1 /* default_opt_level */
> +};
> +
> +static struct tune_params olympus_tunings =
> +{
> + &cortexa76_extra_costs,
> + &generic_armv9_a_addrcost_table,
> + &olympus_regmove_cost,
> + &olympus_vector_cost,
> + &generic_branch_cost,
> + &generic_approx_modes,
> + SVE_128, /* sve_width */
> + { 4, /* load_int. */
> + 1, /* store_int. */
> + 6, /* load_fp. */
> + 3, /* store_fp. */
> + 5, /* load_pred. */
> + 1 /* store_pred. */
> + }, /* memmov_cost. */
> + 10, /* issue_rate */
> + AARCH64_FUSE_NEOVERSE_BASE, /* fusible_ops */
> + "32:16", /* function_align. */
> + "4", /* jump_align. */
> + "32:16", /* loop_align. */
> + 8, /* int_reassoc_width. */
> + 6, /* fp_reassoc_width. */
> + 4, /* fma_reassoc_width. */
> + 6, /* vec_reassoc_width. */
> + 2, /* min_div_recip_mul_sf. */
> + 2, /* min_div_recip_mul_df. */
> + 0, /* max_case_values. */
> + tune_params::AUTOPREFETCHER_WEAK, /* autoprefetcher_model. */
> + (AARCH64_EXTRA_TUNE_BASE
> + | AARCH64_EXTRA_TUNE_CSE_SVE_VL_CONSTANTS
> + | AARCH64_EXTRA_TUNE_MATCHED_VECTOR_THROUGHPUT
> + | AARCH64_EXTRA_TUNE_AVOID_PRED_RMW), /* tune_flags. */
> + &olympus_prefetch_tune,
> + AARCH64_LDP_STP_POLICY_ALWAYS, /* ldp_policy_model. */
> + AARCH64_LDP_STP_POLICY_ALWAYS /* stp_policy_model. */
> +};
> +
> +#endif /* GCC_AARCH64_H_OLYMPUS. */
> --
> 2.34.1
>
