Hi Manos,
> -----Original Message-----
> From: Manos Anagnostakis <manos.anagnosta...@vrull.eu>
> Sent: Tuesday, September 26, 2023 2:52 PM
> To: gcc-patches@gcc.gnu.org
> Cc: Kyrylo Tkachov <kyrylo.tkac...@arm.com>; Tamar Christina
> <tamar.christ...@arm.com>; Philipp Tomsich <philipp.toms...@vrull.eu>;
> Manos Anagnostakis <manos.anagnosta...@vrull.eu>
> Subject: [PATCH v4] aarch64: Fine-grained policies to control ldp-stp
> formation.
>
> This patch implements the following TODO in gcc/config/aarch64/aarch64.cc
> to provide the requested behaviour for handling ldp and stp:
>
> /* Allow the tuning structure to disable LDP instruction formation
> from combining instructions (e.g., in peephole2).
> TODO: Implement fine-grained tuning control for LDP and STP:
> 1. control policies for load and store separately;
> 2. support the following policies:
> - default (use what is in the tuning structure)
> - always
> - never
> - aligned (only if the compiler can prove that the
> load will be aligned to 2 * element_size) */
>
> It provides two new and concrete target-specific command-line parameters
> -param=aarch64-ldp-policy= and -param=aarch64-stp-policy=
> to give the ability to control load and store policies seperately as
> stated in part 1 of the TODO.
>
> The accepted values for both parameters are:
> - default: Use the policy of the tuning structure (default).
> - always: Emit ldp/stp regardless of alignment.
> - never: Do not emit ldp/stp.
> - aligned: In order to emit ldp/stp, first check if the load/store will
> be aligned to 2 * element_size.
>
> Bootstrapped and regtested aarch64-linux.
>
> gcc/ChangeLog:
> * config/aarch64/aarch64-opts.h (enum aarch64_ldp_policy): New
> enum type.
> (enum aarch64_stp_policy): New enum type.
> * config/aarch64/aarch64-protos.h (struct tune_params): Add
> appropriate enums for the policies.
> (aarch64_mem_ok_with_ldpstp_policy_model): New declaration.
> * config/aarch64/aarch64-tuning-flags.def
> (AARCH64_EXTRA_TUNING_OPTION): Remove superseded tuning
> options.
> * config/aarch64/aarch64.cc (aarch64_parse_ldp_policy): New
> function to parse ldp-policy parameter.
> (aarch64_parse_stp_policy): New function to parse stp-policy
> parameter.
> (aarch64_override_options_internal): Call parsing functions.
> (aarch64_mem_ok_with_ldpstp_policy_model): New function.
> (aarch64_operands_ok_for_ldpstp): Add call to
> aarch64_mem_ok_with_ldpstp_policy_model for parameter-value
> check and alignment check and remove superseded ones.
> (aarch64_operands_adjust_ok_for_ldpstp): Add call to
> aarch64_mem_ok_with_ldpstp_policy_model for parameter-value
> check and alignment check and remove superseded ones.
> * config/aarch64/aarch64.opt: Add parameters.
> * doc/invoke.texi: Document the parameters accordingly.
The ChangeLog entry should name the new parameters. For example:
* config/aarch64/aarch64.opt (aarch64-ldp-policy): New param.
Ok with the fixed ChangeLog.
Thank you for the work!
Kyrill
>
> gcc/testsuite/ChangeLog:
> * gcc.target/aarch64/ampere1-no_ldp_combine.c: Removed.
> * gcc.target/aarch64/ldp_aligned.c: New test.
> * gcc.target/aarch64/ldp_always.c: New test.
> * gcc.target/aarch64/ldp_never.c: New test.
> * gcc.target/aarch64/stp_aligned.c: New test.
> * gcc.target/aarch64/stp_always.c: New test.
> * gcc.target/aarch64/stp_never.c: New test.
>
> Signed-off-by: Manos Anagnostakis <manos.anagnosta...@vrull.eu>
> ---
> Changes in v4:
> - Changed the parameters to accept enum instead of an
> integer and updated documentation in doc/invoke.texi.
> - Packed all the new checks in aarch64_operands_ok_for_ldpstp/
> aarch64_operands_adjust_ok_for_ldpstp in a new function
> called aarch64_mem_ok_with_ldpstp_policy_model.
>
> gcc/config/aarch64/aarch64-opts.h | 16 ++
> gcc/config/aarch64/aarch64-protos.h | 25 +++
> gcc/config/aarch64/aarch64-tuning-flags.def | 8 -
> gcc/config/aarch64/aarch64.cc | 212 +++++++++++++-----
> gcc/config/aarch64/aarch64.opt | 38 ++++
> gcc/doc/invoke.texi | 20 ++
> .../aarch64/ampere1-no_ldp_combine.c | 11 -
> .../gcc.target/aarch64/ldp_aligned.c | 66 ++++++
> gcc/testsuite/gcc.target/aarch64/ldp_always.c | 66 ++++++
> gcc/testsuite/gcc.target/aarch64/ldp_never.c | 66 ++++++
> .../gcc.target/aarch64/stp_aligned.c | 60 +++++
> gcc/testsuite/gcc.target/aarch64/stp_always.c | 60 +++++
> gcc/testsuite/gcc.target/aarch64/stp_never.c | 60 +++++
> 13 files changed, 632 insertions(+), 76 deletions(-)
> delete mode 100644 gcc/testsuite/gcc.target/aarch64/ampere1-
> no_ldp_combine.c
> create mode 100644 gcc/testsuite/gcc.target/aarch64/ldp_aligned.c
> create mode 100644 gcc/testsuite/gcc.target/aarch64/ldp_always.c
> create mode 100644 gcc/testsuite/gcc.target/aarch64/ldp_never.c
> create mode 100644 gcc/testsuite/gcc.target/aarch64/stp_aligned.c
> create mode 100644 gcc/testsuite/gcc.target/aarch64/stp_always.c
> create mode 100644 gcc/testsuite/gcc.target/aarch64/stp_never.c
>
> diff --git a/gcc/config/aarch64/aarch64-opts.h b/gcc/config/aarch64/aarch64-
> opts.h
> index 7e8f1babed8..db8348507a3 100644
> --- a/gcc/config/aarch64/aarch64-opts.h
> +++ b/gcc/config/aarch64/aarch64-opts.h
> @@ -108,4 +108,20 @@ enum aarch64_key_type {
> AARCH64_KEY_B
> };
>
> +/* Load pair policy type. */
> +enum aarch64_ldp_policy {
> + LDP_POLICY_DEFAULT,
> + LDP_POLICY_ALWAYS,
> + LDP_POLICY_NEVER,
> + LDP_POLICY_ALIGNED
> +};
> +
> +/* Store pair policy type. */
> +enum aarch64_stp_policy {
> + STP_POLICY_DEFAULT,
> + STP_POLICY_ALWAYS,
> + STP_POLICY_NEVER,
> + STP_POLICY_ALIGNED
> +};
> +
> #endif
> diff --git a/gcc/config/aarch64/aarch64-protos.h
> b/gcc/config/aarch64/aarch64-protos.h
> index 70303d6fd95..3c8f4186689 100644
> --- a/gcc/config/aarch64/aarch64-protos.h
> +++ b/gcc/config/aarch64/aarch64-protos.h
> @@ -568,6 +568,30 @@ struct tune_params
> /* Place prefetch struct pointer at the end to enable type checking
> errors when tune_params misses elements (e.g., from erroneous merges).
> */
> const struct cpu_prefetch_tune *prefetch;
> +/* An enum specifying how to handle load pairs using a fine-grained policy:
> + - LDP_POLICY_ALIGNED: Emit ldp if the source pointer is aligned
> + to at least double the alignment of the type.
> + - LDP_POLICY_ALWAYS: Emit ldp regardless of alignment.
> + - LDP_POLICY_NEVER: Do not emit ldp. */
> +
> + enum aarch64_ldp_policy_model
> + {
> + LDP_POLICY_ALIGNED,
> + LDP_POLICY_ALWAYS,
> + LDP_POLICY_NEVER
> + } ldp_policy_model;
> +/* An enum specifying how to handle store pairs using a fine-grained policy:
> + - STP_POLICY_ALIGNED: Emit stp if the source pointer is aligned
> + to at least double the alignment of the type.
> + - STP_POLICY_ALWAYS: Emit stp regardless of alignment.
> + - STP_POLICY_NEVER: Do not emit stp. */
> +
> + enum aarch64_stp_policy_model
> + {
> + STP_POLICY_ALIGNED,
> + STP_POLICY_ALWAYS,
> + STP_POLICY_NEVER
> + } stp_policy_model;
> };
>
> /* Classifies an address.
> @@ -1015,6 +1039,7 @@ bool extract_base_offset_in_addr (rtx mem, rtx
> *base, rtx *offset);
> bool aarch64_mergeable_load_pair_p (machine_mode, rtx, rtx);
> bool aarch64_operands_ok_for_ldpstp (rtx *, bool, machine_mode);
> bool aarch64_operands_adjust_ok_for_ldpstp (rtx *, bool, machine_mode);
> +bool aarch64_mem_ok_with_ldpstp_policy_model (rtx, bool,
> machine_mode);
> void aarch64_swap_ldrstr_operands (rtx *, bool);
>
> extern void aarch64_asm_output_pool_epilogue (FILE *, const char *,
> diff --git a/gcc/config/aarch64/aarch64-tuning-flags.def
> b/gcc/config/aarch64/aarch64-tuning-flags.def
> index 52112ba7c48..774568e9106 100644
> --- a/gcc/config/aarch64/aarch64-tuning-flags.def
> +++ b/gcc/config/aarch64/aarch64-tuning-flags.def
> @@ -30,11 +30,6 @@
>
> AARCH64_EXTRA_TUNING_OPTION ("rename_fma_regs",
> RENAME_FMA_REGS)
>
> -/* Don't create non-8 byte aligned load/store pair. That is if the
> -two load/stores are not at least 8 byte aligned don't create load/store
> -pairs. */
> -AARCH64_EXTRA_TUNING_OPTION ("slow_unaligned_ldpw",
> SLOW_UNALIGNED_LDPW)
> -
> /* Some of the optional shift to some arthematic instructions are
> considered cheap. Logical shift left <=4 with or without a
> zero extend are considered cheap. Sign extend; non logical shift left
> @@ -44,9 +39,6 @@ AARCH64_EXTRA_TUNING_OPTION
> ("cheap_shift_extend", CHEAP_SHIFT_EXTEND)
> /* Disallow load/store pair instructions on Q-registers. */
> AARCH64_EXTRA_TUNING_OPTION ("no_ldp_stp_qregs",
> NO_LDP_STP_QREGS)
>
> -/* Disallow load-pair instructions to be formed in combine/peephole. */
> -AARCH64_EXTRA_TUNING_OPTION ("no_ldp_combine", NO_LDP_COMBINE)
> -
> AARCH64_EXTRA_TUNING_OPTION ("rename_load_regs",
> RENAME_LOAD_REGS)
>
> AARCH64_EXTRA_TUNING_OPTION ("cse_sve_vl_constants",
> CSE_SVE_VL_CONSTANTS)
> diff --git a/gcc/config/aarch64/aarch64.cc b/gcc/config/aarch64/aarch64.cc
> index 219c4ee6d4c..f1e98ea1ab6 100644
> --- a/gcc/config/aarch64/aarch64.cc
> +++ b/gcc/config/aarch64/aarch64.cc
> @@ -1357,7 +1357,9 @@ static const struct tune_params generic_tunings =
> Neoverse V1. It does not have a noticeable effect on A64FX and should
> have at most a very minor effect on SVE2 cores. */
> (AARCH64_EXTRA_TUNE_CSE_SVE_VL_CONSTANTS), /* tune_flags. */
> - &generic_prefetch_tune
> + &generic_prefetch_tune,
> + tune_params::LDP_POLICY_ALWAYS, /* ldp_policy_model. */
> + tune_params::STP_POLICY_ALWAYS /* stp_policy_model. */
> };
>
> static const struct tune_params cortexa35_tunings =
> @@ -1391,7 +1393,9 @@ static const struct tune_params cortexa35_tunings
> =
> 0, /* max_case_values. */
> tune_params::AUTOPREFETCHER_WEAK, /* autoprefetcher_model. */
> (AARCH64_EXTRA_TUNE_NONE), /* tune_flags. */
> - &generic_prefetch_tune
> + &generic_prefetch_tune,
> + tune_params::LDP_POLICY_ALWAYS, /* ldp_policy_model. */
> + tune_params::STP_POLICY_ALWAYS /* stp_policy_model. */
> };
>
> static const struct tune_params cortexa53_tunings =
> @@ -1425,7 +1429,9 @@ static const struct tune_params cortexa53_tunings
> =
> 0, /* max_case_values. */
> tune_params::AUTOPREFETCHER_WEAK, /* autoprefetcher_model. */
> (AARCH64_EXTRA_TUNE_NONE), /* tune_flags. */
> - &generic_prefetch_tune
> + &generic_prefetch_tune,
> + tune_params::LDP_POLICY_ALWAYS, /* ldp_policy_model. */
> + tune_params::STP_POLICY_ALWAYS /* stp_policy_model. */
> };
>
> static const struct tune_params cortexa57_tunings =
> @@ -1459,7 +1465,9 @@ static const struct tune_params cortexa57_tunings
> =
> 0, /* max_case_values. */
> tune_params::AUTOPREFETCHER_WEAK, /* autoprefetcher_model. */
> (AARCH64_EXTRA_TUNE_RENAME_FMA_REGS), /* tune_flags. */
> - &generic_prefetch_tune
> + &generic_prefetch_tune,
> + tune_params::LDP_POLICY_ALWAYS, /* ldp_policy_model. */
> + tune_params::STP_POLICY_ALWAYS /* stp_policy_model. */
> };
>
> static const struct tune_params cortexa72_tunings =
> @@ -1493,7 +1501,9 @@ static const struct tune_params cortexa72_tunings
> =
> 0, /* max_case_values. */
> tune_params::AUTOPREFETCHER_WEAK, /* autoprefetcher_model. */
> (AARCH64_EXTRA_TUNE_NONE), /* tune_flags. */
> - &generic_prefetch_tune
> + &generic_prefetch_tune,
> + tune_params::LDP_POLICY_ALWAYS, /* ldp_policy_model. */
> + tune_params::STP_POLICY_ALWAYS /* stp_policy_model. */
> };
>
> static const struct tune_params cortexa73_tunings =
> @@ -1527,7 +1537,9 @@ static const struct tune_params cortexa73_tunings
> =
> 0, /* max_case_values. */
> tune_params::AUTOPREFETCHER_WEAK, /* autoprefetcher_model. */
> (AARCH64_EXTRA_TUNE_NONE), /* tune_flags. */
> - &generic_prefetch_tune
> + &generic_prefetch_tune,
> + tune_params::LDP_POLICY_ALWAYS, /* ldp_policy_model. */
> + tune_params::STP_POLICY_ALWAYS /* stp_policy_model. */
> };
>
>
> @@ -1562,7 +1574,9 @@ static const struct tune_params exynosm1_tunings
> =
> 48, /* max_case_values. */
> tune_params::AUTOPREFETCHER_WEAK, /* autoprefetcher_model. */
> (AARCH64_EXTRA_TUNE_NONE), /* tune_flags. */
> - &exynosm1_prefetch_tune
> + &exynosm1_prefetch_tune,
> + tune_params::LDP_POLICY_ALWAYS, /* ldp_policy_model. */
> + tune_params::STP_POLICY_ALWAYS /* stp_policy_model. */
> };
>
> static const struct tune_params thunderxt88_tunings =
> @@ -1594,8 +1608,10 @@ static const struct tune_params
> thunderxt88_tunings =
> 2, /* min_div_recip_mul_df. */
> 0, /* max_case_values. */
> tune_params::AUTOPREFETCHER_OFF, /* autoprefetcher_model. */
> - (AARCH64_EXTRA_TUNE_SLOW_UNALIGNED_LDPW), /* tune_flags. */
> - &thunderxt88_prefetch_tune
> + (AARCH64_EXTRA_TUNE_NONE), /* tune_flags. */
> + &thunderxt88_prefetch_tune,
> + tune_params::LDP_POLICY_ALIGNED, /* ldp_policy_model. */
> + tune_params::STP_POLICY_ALIGNED /* stp_policy_model. */
> };
>
> static const struct tune_params thunderx_tunings =
> @@ -1627,9 +1643,10 @@ static const struct tune_params thunderx_tunings
> =
> 2, /* min_div_recip_mul_df. */
> 0, /* max_case_values. */
> tune_params::AUTOPREFETCHER_OFF, /* autoprefetcher_model. */
> - (AARCH64_EXTRA_TUNE_SLOW_UNALIGNED_LDPW
> - | AARCH64_EXTRA_TUNE_CHEAP_SHIFT_EXTEND), /* tune_flags. */
> - &thunderx_prefetch_tune
> + (AARCH64_EXTRA_TUNE_CHEAP_SHIFT_EXTEND), /* tune_flags. */
> + &thunderx_prefetch_tune,
> + tune_params::LDP_POLICY_ALIGNED, /* ldp_policy_model. */
> + tune_params::STP_POLICY_ALIGNED /* stp_policy_model. */
> };
>
> static const struct tune_params tsv110_tunings =
> @@ -1663,7 +1680,9 @@ static const struct tune_params tsv110_tunings =
> 0, /* max_case_values. */
> tune_params::AUTOPREFETCHER_WEAK, /* autoprefetcher_model. */
> (AARCH64_EXTRA_TUNE_NONE), /* tune_flags. */
> - &tsv110_prefetch_tune
> + &tsv110_prefetch_tune,
> + tune_params::LDP_POLICY_ALWAYS, /* ldp_policy_model. */
> + tune_params::STP_POLICY_ALWAYS /* stp_policy_model. */
> };
>
> static const struct tune_params xgene1_tunings =
> @@ -1696,7 +1715,9 @@ static const struct tune_params xgene1_tunings =
> 17, /* max_case_values. */
> tune_params::AUTOPREFETCHER_OFF, /* autoprefetcher_model. */
> (AARCH64_EXTRA_TUNE_NO_LDP_STP_QREGS), /* tune_flags. */
> - &xgene1_prefetch_tune
> + &xgene1_prefetch_tune,
> + tune_params::LDP_POLICY_ALWAYS, /* ldp_policy_model. */
> + tune_params::STP_POLICY_ALWAYS /* stp_policy_model. */
> };
>
> static const struct tune_params emag_tunings =
> @@ -1729,7 +1750,9 @@ static const struct tune_params emag_tunings =
> 17, /* max_case_values. */
> tune_params::AUTOPREFETCHER_OFF, /* autoprefetcher_model. */
> (AARCH64_EXTRA_TUNE_NO_LDP_STP_QREGS), /* tune_flags. */
> - &xgene1_prefetch_tune
> + &xgene1_prefetch_tune,
> + tune_params::LDP_POLICY_ALWAYS, /* ldp_policy_model. */
> + tune_params::STP_POLICY_ALWAYS /* stp_policy_model. */
> };
>
> static const struct tune_params qdf24xx_tunings =
> @@ -1763,7 +1786,9 @@ static const struct tune_params qdf24xx_tunings =
> 0, /* max_case_values. */
> tune_params::AUTOPREFETCHER_WEAK, /* autoprefetcher_model. */
> AARCH64_EXTRA_TUNE_RENAME_LOAD_REGS, /* tune_flags. */
> - &qdf24xx_prefetch_tune
> + &qdf24xx_prefetch_tune,
> + tune_params::LDP_POLICY_ALWAYS, /* ldp_policy_model. */
> + tune_params::STP_POLICY_ALWAYS /* stp_policy_model. */
> };
>
> /* Tuning structure for the Qualcomm Saphira core. Default to falkor values
> @@ -1799,7 +1824,9 @@ static const struct tune_params saphira_tunings =
> 0, /* max_case_values. */
> tune_params::AUTOPREFETCHER_WEAK, /* autoprefetcher_model. */
> (AARCH64_EXTRA_TUNE_NONE), /* tune_flags. */
> - &generic_prefetch_tune
> + &generic_prefetch_tune,
> + tune_params::LDP_POLICY_ALWAYS, /* ldp_policy_model. */
> + tune_params::STP_POLICY_ALWAYS /* stp_policy_model. */
> };
>
> static const struct tune_params thunderx2t99_tunings =
> @@ -1833,7 +1860,9 @@ static const struct tune_params
> thunderx2t99_tunings =
> 0, /* max_case_values. */
> tune_params::AUTOPREFETCHER_WEAK, /* autoprefetcher_model. */
> (AARCH64_EXTRA_TUNE_NONE), /* tune_flags. */
> - &thunderx2t99_prefetch_tune
> + &thunderx2t99_prefetch_tune,
> + tune_params::LDP_POLICY_ALWAYS, /* ldp_policy_model. */
> + tune_params::STP_POLICY_ALWAYS /* stp_policy_model. */
> };
>
> static const struct tune_params thunderx3t110_tunings =
> @@ -1867,7 +1896,9 @@ static const struct tune_params
> thunderx3t110_tunings =
> 0, /* max_case_values. */
> tune_params::AUTOPREFETCHER_WEAK, /* autoprefetcher_model. */
> (AARCH64_EXTRA_TUNE_NONE), /* tune_flags. */
> - &thunderx3t110_prefetch_tune
> + &thunderx3t110_prefetch_tune,
> + tune_params::LDP_POLICY_ALWAYS, /* ldp_policy_model. */
> + tune_params::STP_POLICY_ALWAYS /* stp_policy_model. */
> };
>
> static const struct tune_params neoversen1_tunings =
> @@ -1900,7 +1931,9 @@ static const struct tune_params
> neoversen1_tunings =
> 0, /* max_case_values. */
> tune_params::AUTOPREFETCHER_WEAK, /* autoprefetcher_model. */
> (AARCH64_EXTRA_TUNE_CHEAP_SHIFT_EXTEND), /* tune_flags. */
> - &generic_prefetch_tune
> + &generic_prefetch_tune,
> + tune_params::LDP_POLICY_ALWAYS, /* ldp_policy_model. */
> + tune_params::STP_POLICY_ALWAYS /* stp_policy_model. */
> };
>
> static const struct tune_params ampere1_tunings =
> @@ -1936,8 +1969,10 @@ static const struct tune_params ampere1_tunings
> =
> 2, /* min_div_recip_mul_df. */
> 0, /* max_case_values. */
> tune_params::AUTOPREFETCHER_WEAK, /* autoprefetcher_model. */
> - (AARCH64_EXTRA_TUNE_NO_LDP_COMBINE), /* tune_flags. */
> - &ere1_prefetch_tune
> + (AARCH64_EXTRA_TUNE_NONE), /* tune_flags. */
> + &ere1_prefetch_tune,
> + tune_params::LDP_POLICY_ALIGNED, /* ldp_policy_model. */
> + tune_params::STP_POLICY_ALIGNED /* stp_policy_model. */
> };
>
> static const struct tune_params ampere1a_tunings =
> @@ -1974,8 +2009,10 @@ static const struct tune_params ampere1a_tunings
> =
> 2, /* min_div_recip_mul_df. */
> 0, /* max_case_values. */
> tune_params::AUTOPREFETCHER_WEAK, /* autoprefetcher_model. */
> - (AARCH64_EXTRA_TUNE_NO_LDP_COMBINE), /* tune_flags. */
> - &ere1_prefetch_tune
> + (AARCH64_EXTRA_TUNE_NONE), /* tune_flags. */
> + &ere1_prefetch_tune,
> + tune_params::LDP_POLICY_ALIGNED, /* ldp_policy_model. */
> + tune_params::STP_POLICY_ALIGNED /* stp_policy_model. */
> };
>
> static const advsimd_vec_cost neoversev1_advsimd_vector_cost =
> @@ -2156,7 +2193,9 @@ static const struct tune_params
> neoversev1_tunings =
> | AARCH64_EXTRA_TUNE_USE_NEW_VECTOR_COSTS
> | AARCH64_EXTRA_TUNE_MATCHED_VECTOR_THROUGHPUT
> | AARCH64_EXTRA_TUNE_CHEAP_SHIFT_EXTEND), /* tune_flags. */
> - &generic_prefetch_tune
> + &generic_prefetch_tune,
> + tune_params::LDP_POLICY_ALWAYS, /* ldp_policy_model. */
> + tune_params::STP_POLICY_ALWAYS /* stp_policy_model. */
> };
>
> static const sve_vec_cost neoverse512tvb_sve_vector_cost =
> @@ -2293,7 +2332,9 @@ static const struct tune_params
> neoverse512tvb_tunings =
> (AARCH64_EXTRA_TUNE_CSE_SVE_VL_CONSTANTS
> | AARCH64_EXTRA_TUNE_USE_NEW_VECTOR_COSTS
> | AARCH64_EXTRA_TUNE_MATCHED_VECTOR_THROUGHPUT), /*
> tune_flags. */
> - &generic_prefetch_tune
> + &generic_prefetch_tune,
> + tune_params::LDP_POLICY_ALWAYS, /* ldp_policy_model. */
> + tune_params::STP_POLICY_ALWAYS /* stp_policy_model. */
> };
>
> static const advsimd_vec_cost neoversen2_advsimd_vector_cost =
> @@ -2483,7 +2524,9 @@ static const struct tune_params
> neoversen2_tunings =
> | AARCH64_EXTRA_TUNE_CSE_SVE_VL_CONSTANTS
> | AARCH64_EXTRA_TUNE_USE_NEW_VECTOR_COSTS
> | AARCH64_EXTRA_TUNE_MATCHED_VECTOR_THROUGHPUT), /*
> tune_flags. */
> - &generic_prefetch_tune
> + &generic_prefetch_tune,
> + tune_params::LDP_POLICY_ALWAYS, /* ldp_policy_model. */
> + tune_params::STP_POLICY_ALWAYS /* stp_policy_model. */
> };
>
> static const advsimd_vec_cost neoversev2_advsimd_vector_cost =
> @@ -2673,7 +2716,9 @@ static const struct tune_params
> neoversev2_tunings =
> | AARCH64_EXTRA_TUNE_CSE_SVE_VL_CONSTANTS
> | AARCH64_EXTRA_TUNE_USE_NEW_VECTOR_COSTS
> | AARCH64_EXTRA_TUNE_MATCHED_VECTOR_THROUGHPUT), /*
> tune_flags. */
> - &generic_prefetch_tune
> + &generic_prefetch_tune,
> + tune_params::LDP_POLICY_ALWAYS, /* ldp_policy_model. */
> + tune_params::STP_POLICY_ALWAYS /* stp_policy_model. */
> };
>
> static const struct tune_params a64fx_tunings =
> @@ -2706,7 +2751,9 @@ static const struct tune_params a64fx_tunings =
> 0, /* max_case_values. */
> tune_params::AUTOPREFETCHER_WEAK, /* autoprefetcher_model. */
> (AARCH64_EXTRA_TUNE_NONE), /* tune_flags. */
> - &a64fx_prefetch_tune
> + &a64fx_prefetch_tune,
> + tune_params::LDP_POLICY_ALWAYS, /* ldp_policy_model. */
> + tune_params::STP_POLICY_ALWAYS /* stp_policy_model. */
> };
>
> /* Support for fine-grained override of the tuning structures. */
> @@ -17819,6 +17866,36 @@ aarch64_parse_tune (const char *to_parse,
> const struct processor **res)
> return AARCH_PARSE_INVALID_ARG;
> }
>
> +/* Parse a command-line -param=aarch64-ldp-policy= parameter. VALUE is
> + the value of the parameter. */
> +
> +static void
> +aarch64_parse_ldp_policy (enum aarch64_ldp_policy value,
> + struct tune_params* tune)
> +{
> + if (value == LDP_POLICY_ALWAYS)
> + tune->ldp_policy_model = tune_params::LDP_POLICY_ALWAYS;
> + else if (value == LDP_POLICY_NEVER)
> + tune->ldp_policy_model = tune_params::LDP_POLICY_NEVER;
> + else if (value == LDP_POLICY_ALIGNED)
> + tune->ldp_policy_model = tune_params::LDP_POLICY_ALIGNED;
> +}
> +
> +/* Parse a command-line -param=aarch64-stp-policy= parameter. VALUE is
> + the value of the parameter. */
> +
> +static void
> +aarch64_parse_stp_policy (enum aarch64_stp_policy value,
> + struct tune_params* tune)
> +{
> + if (value == STP_POLICY_ALWAYS)
> + tune->stp_policy_model = tune_params::STP_POLICY_ALWAYS;
> + else if (value == STP_POLICY_NEVER)
> + tune->stp_policy_model = tune_params::STP_POLICY_NEVER;
> + else if (value == STP_POLICY_ALIGNED)
> + tune->stp_policy_model = tune_params::STP_POLICY_ALIGNED;
> +}
> +
> /* Parse TOKEN, which has length LENGTH to see if it is an option
> described in FLAG. If it is, return the index bit for that fusion type.
> If not, error (printing OPTION_NAME) and return zero. */
> @@ -18167,6 +18244,14 @@ aarch64_override_options_internal (struct
> gcc_options *opts)
> aarch64_parse_override_string (opts->x_aarch64_override_tune_string,
> &aarch64_tune_params);
>
> + if (opts->x_aarch64_ldp_policy_param)
> + aarch64_parse_ldp_policy (opts->x_aarch64_ldp_policy_param,
> + &aarch64_tune_params);
> +
> + if (opts->x_aarch64_stp_policy_param)
> + aarch64_parse_stp_policy (opts->x_aarch64_stp_policy_param,
> + &aarch64_tune_params);
> +
> /* This target defaults to strict volatile bitfields. */
> if (opts->x_flag_strict_volatile_bitfields < 0 && abi_version_at_least (2))
> opts->x_flag_strict_volatile_bitfields = 1;
> @@ -26457,6 +26542,43 @@ aarch64_mergeable_load_pair_p
> (machine_mode mode, rtx mem1, rtx mem2)
> return aarch64_check_consecutive_mems (&mem1, &mem2, nullptr);
> }
>
> +/* Return true if MEM agrees with the ldp-stp policy model.
> + Otherwise, false. */
> +
> +bool
> +aarch64_mem_ok_with_ldpstp_policy_model (rtx mem, bool load,
> machine_mode mode)
> +{
> + /* If we have LDP_POLICY_NEVER, reject the load pair. */
> + if (load
> + && aarch64_tune_params.ldp_policy_model ==
> tune_params::LDP_POLICY_NEVER)
> + return false;
> +
> + /* If we have STP_POLICY_NEVER, reject the store pair. */
> + if (!load
> + && aarch64_tune_params.stp_policy_model ==
> tune_params::STP_POLICY_NEVER)
> + return false;
> +
> + /* If we have LDP_POLICY_ALIGNED,
> + do not emit the load pair unless the alignment is checked to be
> + at least double the alignment of the type. */
> + if (load
> + && aarch64_tune_params.ldp_policy_model ==
> tune_params::LDP_POLICY_ALIGNED
> + && !optimize_function_for_size_p (cfun)
> + && MEM_ALIGN (mem) < 2 * GET_MODE_ALIGNMENT (mode))
> + return false;
> +
> + /* If we have STP_POLICY_ALIGNED,
> + do not emit the store pair unless the alignment is checked to be
> + at least double the alignment of the type. */
> + if (!load
> + && aarch64_tune_params.stp_policy_model ==
> tune_params::STP_POLICY_ALIGNED
> + && !optimize_function_for_size_p (cfun)
> + && MEM_ALIGN (mem) < 2 * GET_MODE_ALIGNMENT (mode))
> + return false;
> +
> + return true;
> +}
> +
> /* Given OPERANDS of consecutive load/store, check if we can merge
> them into ldp/stp. LOAD is true if they are load instructions.
> MODE is the mode of memory operands. */
> @@ -26468,20 +26590,6 @@ aarch64_operands_ok_for_ldpstp (rtx
> *operands, bool load,
> enum reg_class rclass_1, rclass_2;
> rtx mem_1, mem_2, reg_1, reg_2;
>
> - /* Allow the tuning structure to disable LDP instruction formation
> - from combining instructions (e.g., in peephole2).
> - TODO: Implement fine-grained tuning control for LDP and STP:
> - 1. control policies for load and store separately;
> - 2. support the following policies:
> - - default (use what is in the tuning structure)
> - - always
> - - never
> - - aligned (only if the compiler can prove that the
> - load will be aligned to 2 * element_size) */
> - if (load && (aarch64_tune_params.extra_tuning_flags
> - & AARCH64_EXTRA_TUNE_NO_LDP_COMBINE))
> - return false;
> -
> if (load)
> {
> mem_1 = operands[1];
> @@ -26506,13 +26614,8 @@ aarch64_operands_ok_for_ldpstp (rtx
> *operands, bool load,
> if (MEM_VOLATILE_P (mem_1) || MEM_VOLATILE_P (mem_2))
> return false;
>
> - /* If we have SImode and slow unaligned ldp,
> - check the alignment to be at least 8 byte. */
> - if (mode == SImode
> - && (aarch64_tune_params.extra_tuning_flags
> - & AARCH64_EXTRA_TUNE_SLOW_UNALIGNED_LDPW)
> - && !optimize_size
> - && MEM_ALIGN (mem_1) < 8 * BITS_PER_UNIT)
> + /* Check if mem_1 is ok with the ldp-stp policy model. */
> + if (!aarch64_mem_ok_with_ldpstp_policy_model (mem_1, load, mode))
> return false;
>
> /* Check if the addresses are in the form of [base+offset]. */
> @@ -26729,13 +26832,8 @@ aarch64_operands_adjust_ok_for_ldpstp (rtx
> *operands, bool load,
> if (offvals[0] % msize != offvals[2] % msize)
> return false;
>
> - /* If we have SImode and slow unaligned ldp,
> - check the alignment to be at least 8 byte. */
> - if (mode == SImode
> - && (aarch64_tune_params.extra_tuning_flags
> - & AARCH64_EXTRA_TUNE_SLOW_UNALIGNED_LDPW)
> - && !optimize_size
> - && MEM_ALIGN (mem[0]) < 8 * BITS_PER_UNIT)
> + /* Check if mem[0] is ok with the ldp-stp policy model. */
> + if (!aarch64_mem_ok_with_ldpstp_policy_model (mem[0], load, mode))
> return false;
>
> return true;
> diff --git a/gcc/config/aarch64/aarch64.opt b/gcc/config/aarch64/aarch64.opt
> index 4a0580435a8..2101c5a23c4 100644
> --- a/gcc/config/aarch64/aarch64.opt
> +++ b/gcc/config/aarch64/aarch64.opt
> @@ -337,3 +337,41 @@ Constant memset size in bytes from which to start
> using MOPS sequence.
> -param=aarch64-vect-unroll-limit=
> Target Joined UInteger Var(aarch64_vect_unroll_limit) Init(4) Param
> Limit how much the autovectorizer may unroll a loop.
> +
> +-param=aarch64-ldp-policy=
> +Target Joined Var(aarch64_ldp_policy_param) Enum(aarch64_ldp_policy)
> Init(LDP_POLICY_DEFAULT) Param
> +--param=aarch64-ldp-policy=[default|always|never|aligned] Fine-grained
> policy for load pairs.
> +
> +Enum
> +Name(aarch64_ldp_policy) Type(enum aarch64_ldp_policy)
> UnknownError(unknown aarch64_ldp_policy mode %qs)
> +
> +EnumValue
> +Enum(aarch64_ldp_policy) String(default) Value(LDP_POLICY_DEFAULT)
> +
> +EnumValue
> +Enum(aarch64_ldp_policy) String(always) Value(LDP_POLICY_ALWAYS)
> +
> +EnumValue
> +Enum(aarch64_ldp_policy) String(never) Value(LDP_POLICY_NEVER)
> +
> +EnumValue
> +Enum(aarch64_ldp_policy) String(aligned) Value(LDP_POLICY_ALIGNED)
> +
> +-param=aarch64-stp-policy=
> +Target Joined Var(aarch64_stp_policy_param) Enum(aarch64_stp_policy)
> Init(STP_POLICY_DEFAULT) Param
> +--param=aarch64-stp-policy=[default|always|never|aligned] Fine-grained
> policy for store pairs.
> +
> +Enum
> +Name(aarch64_stp_policy) Type(enum aarch64_stp_policy)
> UnknownError(unknown aarch64_stp_policy mode %qs)
> +
> +EnumValue
> +Enum(aarch64_stp_policy) String(default) Value(STP_POLICY_DEFAULT)
> +
> +EnumValue
> +Enum(aarch64_stp_policy) String(always) Value(STP_POLICY_ALWAYS)
> +
> +EnumValue
> +Enum(aarch64_stp_policy) String(never) Value(STP_POLICY_NEVER)
> +
> +EnumValue
> +Enum(aarch64_stp_policy) String(aligned) Value(STP_POLICY_ALIGNED)
> diff --git a/gcc/doc/invoke.texi b/gcc/doc/invoke.texi
> index 146b40414b0..c844a58b508 100644
> --- a/gcc/doc/invoke.texi
> +++ b/gcc/doc/invoke.texi
> @@ -16508,6 +16508,26 @@ Use both Advanced SIMD and SVE. Prefer SVE
> when the costs are deemed equal.
> @end table
> The default value is 0.
>
> +@item aarch64-ldp-policy
> +Fine-grained policy for load pairs.
> +With @option{--param=aarch64-ldp-policy=default}, use the policy of the
> +tuning structure. This is the current default.
> +With @option{--param=aarch64-ldp-policy=always}, emit ldp regardless
> +of alignment.
> +With @option{--param=aarch64-ldp-policy=never}, do not emit ldp.
> +With @option{--param=aarch64-ldp-policy=aligned}, emit ldp only if the
> +source pointer is aligned to at least double the alignment of the type.
> +
> +@item aarch64-stp-policy
> +Fine-grained policy for store pairs.
> +With @option{--param=aarch64-stp-policy=default}, use the policy of the
> +tuning structure. This is the current default.
> +With @option{--param=aarch64-stp-policy=always}, emit stp regardless
> +of alignment.
> +With @option{--param=aarch64-stp-policy=never}, do not emit stp.
> +With @option{--param=aarch64-stp-policy=aligned}, emit stp only if the
> +source pointer is aligned to at least double the alignment of the type.
> +
> @item aarch64-loop-vect-issue-rate-niters
> The tuning for some AArch64 CPUs tries to take both latencies and issue
> rates into account when deciding whether a loop should be vectorized
> diff --git a/gcc/testsuite/gcc.target/aarch64/ampere1-no_ldp_combine.c
> b/gcc/testsuite/gcc.target/aarch64/ampere1-no_ldp_combine.c
> deleted file mode 100644
> index bc871f4481d..00000000000
> --- a/gcc/testsuite/gcc.target/aarch64/ampere1-no_ldp_combine.c
> +++ /dev/null
> @@ -1,11 +0,0 @@
> -/* { dg-options "-O3 -mtune=ampere1" } */
> -
> -long
> -foo (long a[])
> -{
> - return a[0] + a[1];
> -}
> -
> -/* We should see two ldrs instead of one ldp. */
> -/* { dg-final { scan-assembler {\tldr\t} } } */
> -/* { dg-final { scan-assembler-not {\tldp\t} } } */
> diff --git a/gcc/testsuite/gcc.target/aarch64/ldp_aligned.c
> b/gcc/testsuite/gcc.target/aarch64/ldp_aligned.c
> new file mode 100644
> index 00000000000..f44f9616366
> --- /dev/null
> +++ b/gcc/testsuite/gcc.target/aarch64/ldp_aligned.c
> @@ -0,0 +1,66 @@
> +/* { dg-options "-O2 --param=aarch64-ldp-policy=aligned -mcpu=generic" }
> */
> +
> +#include <stdlib.h>
> +#include <stdint.h>
> +
> +typedef int v4si __attribute__ ((vector_size (16)));
> +
> +#define LDP_TEST_ALIGNED(TYPE) \
> +TYPE ldp_aligned_##TYPE(char* ptr){ \
> + TYPE a_0, a_1; \
> + TYPE *arr = (TYPE*) ((uintptr_t)ptr & ~(2 * 8 * _Alignof(TYPE) - 1)); \
> + a_0 = arr[0]; \
> + a_1 = arr[1]; \
> + return a_0 + a_1; \
> +}
> +
> +#define LDP_TEST_UNALIGNED(TYPE) \
> +TYPE ldp_unaligned_##TYPE(char* ptr){ \
> + TYPE a_0, a_1; \
> + TYPE *arr = (TYPE*) ((uintptr_t)ptr & ~(2 * 8 * _Alignof(TYPE) - 1)); \
> + TYPE *a = arr+1; \
> + a_0 = a[0]; \
> + a_1 = a[1]; \
> + return a_0 + a_1; \
> +}
> +
> +#define LDP_TEST_ADJUST_ALIGNED(TYPE) \
> +TYPE ldp_aligned_adjust_##TYPE(char* ptr){ \
> + TYPE a_0, a_1, a_2, a_3, a_4; \
> + TYPE *arr = (TYPE*) ((uintptr_t)ptr & ~(2 * 8 * _Alignof(TYPE) - 1)); \
> + a_0 = arr[100]; \
> + a_1 = arr[101]; \
> + a_2 = arr[102]; \
> + a_3 = arr[103]; \
> + a_4 = arr[110]; \
> + return a_0 + a_1 + a_2 + a_3 + a_4; \
> +}
> +
> +#define LDP_TEST_ADJUST_UNALIGNED(TYPE) \
> +TYPE ldp_unaligned_adjust_##TYPE(char* ptr){ \
> + TYPE a_0, a_1, a_2, a_3, a_4; \
> + TYPE *arr = (TYPE*) ((uintptr_t)ptr & ~(2 * 8 * _Alignof(TYPE) - 1)); \
> + TYPE *a = arr+1; \
> + a_0 = a[100]; \
> + a_1 = a[101]; \
> + a_2 = a[102]; \
> + a_3 = a[103]; \
> + a_4 = a[110]; \
> + return a_0 + a_1 + a_2 + a_3 + a_4; \
> +}
> +
> +LDP_TEST_ALIGNED(int32_t);
> +LDP_TEST_ALIGNED(int64_t);
> +LDP_TEST_ALIGNED(v4si);
> +LDP_TEST_UNALIGNED(int32_t);
> +LDP_TEST_UNALIGNED(int64_t);
> +LDP_TEST_UNALIGNED(v4si);
> +LDP_TEST_ADJUST_ALIGNED(int32_t);
> +LDP_TEST_ADJUST_ALIGNED(int64_t);
> +LDP_TEST_ADJUST_UNALIGNED(int32_t);
> +LDP_TEST_ADJUST_UNALIGNED(int64_t);
> +
> +/* { dg-final { scan-assembler-times "ldp\tw\[0-9\]+, w\[0-9\]" 3 } } */
> +/* { dg-final { scan-assembler-times "ldp\tx\[0-9\]+, x\[0-9\]" 3 } } */
> +/* { dg-final { scan-assembler-times "ldp\tq\[0-9\]+, q\[0-9\]" 1 } } */
> +
> diff --git a/gcc/testsuite/gcc.target/aarch64/ldp_always.c
> b/gcc/testsuite/gcc.target/aarch64/ldp_always.c
> new file mode 100644
> index 00000000000..9cada57db89
> --- /dev/null
> +++ b/gcc/testsuite/gcc.target/aarch64/ldp_always.c
> @@ -0,0 +1,66 @@
> +/* { dg-options "-O2 --param=aarch64-ldp-policy=always -mcpu=generic" } */
> +
> +#include <stdlib.h>
> +#include <stdint.h>
> +
> +typedef int v4si __attribute__ ((vector_size (16)));
> +
> +#define LDP_TEST_ALIGNED(TYPE) \
> +TYPE ldp_aligned_##TYPE(char* ptr){ \
> + TYPE a_0, a_1; \
> + TYPE *arr = (TYPE*) ((uintptr_t)ptr & ~(2 * 8 * _Alignof(TYPE) - 1)); \
> + a_0 = arr[0]; \
> + a_1 = arr[1]; \
> + return a_0 + a_1; \
> +}
> +
> +#define LDP_TEST_UNALIGNED(TYPE) \
> +TYPE ldp_unaligned_##TYPE(char* ptr){ \
> + TYPE a_0, a_1; \
> + TYPE *arr = (TYPE*) ((uintptr_t)ptr & ~(2 * 8 * _Alignof(TYPE) - 1)); \
> + TYPE *a = arr+1; \
> + a_0 = a[0]; \
> + a_1 = a[1]; \
> + return a_0 + a_1; \
> +}
> +
> +#define LDP_TEST_ADJUST_ALIGNED(TYPE) \
> +TYPE ldp_aligned_adjust_##TYPE(char* ptr){ \
> + TYPE a_0, a_1, a_2, a_3, a_4; \
> + TYPE *arr = (TYPE*) ((uintptr_t)ptr & ~(2 * 8 * _Alignof(TYPE) - 1)); \
> + a_0 = arr[100]; \
> + a_1 = arr[101]; \
> + a_2 = arr[102]; \
> + a_3 = arr[103]; \
> + a_4 = arr[110]; \
> + return a_0 + a_1 + a_2 + a_3 + a_4; \
> +}
> +
> +#define LDP_TEST_ADJUST_UNALIGNED(TYPE) \
> +TYPE ldp_unaligned_adjust_##TYPE(char* ptr){ \
> + TYPE a_0, a_1, a_2, a_3, a_4; \
> + TYPE *arr = (TYPE*) ((uintptr_t)ptr & ~(2 * 8 * _Alignof(TYPE) - 1)); \
> + TYPE *a = arr+1; \
> + a_0 = a[100]; \
> + a_1 = a[101]; \
> + a_2 = a[102]; \
> + a_3 = a[103]; \
> + a_4 = a[110]; \
> + return a_0 + a_1 + a_2 + a_3 + a_4; \
> +}
> +
> +LDP_TEST_ALIGNED(int32_t);
> +LDP_TEST_ALIGNED(int64_t);
> +LDP_TEST_ALIGNED(v4si);
> +LDP_TEST_UNALIGNED(int32_t);
> +LDP_TEST_UNALIGNED(int64_t);
> +LDP_TEST_UNALIGNED(v4si);
> +LDP_TEST_ADJUST_ALIGNED(int32_t);
> +LDP_TEST_ADJUST_ALIGNED(int64_t);
> +LDP_TEST_ADJUST_UNALIGNED(int32_t);
> +LDP_TEST_ADJUST_UNALIGNED(int64_t);
> +
> +/* { dg-final { scan-assembler-times "ldp\tw\[0-9\]+, w\[0-9\]" 6 } } */
> +/* { dg-final { scan-assembler-times "ldp\tx\[0-9\]+, x\[0-9\]" 6 } } */
> +/* { dg-final { scan-assembler-times "ldp\tq\[0-9\]+, q\[0-9\]" 2 } } */
> +
> diff --git a/gcc/testsuite/gcc.target/aarch64/ldp_never.c
> b/gcc/testsuite/gcc.target/aarch64/ldp_never.c
> new file mode 100644
> index 00000000000..64f50439fe9
> --- /dev/null
> +++ b/gcc/testsuite/gcc.target/aarch64/ldp_never.c
> @@ -0,0 +1,66 @@
> +/* { dg-options "-O2 --param=aarch64-ldp-policy=never -mcpu=generic" } */
> +
> +#include <stdlib.h>
> +#include <stdint.h>
> +
> +typedef int v4si __attribute__ ((vector_size (16)));
> +
> +#define LDP_TEST_ALIGNED(TYPE) \
> +TYPE ldp_aligned_##TYPE(char* ptr){ \
> + TYPE a_0, a_1; \
> + TYPE *arr = (TYPE*) ((uintptr_t)ptr & ~(2 * 8 * _Alignof(TYPE) - 1)); \
> + a_0 = arr[0]; \
> + a_1 = arr[1]; \
> + return a_0 + a_1; \
> +}
> +
> +#define LDP_TEST_UNALIGNED(TYPE) \
> +TYPE ldp_unaligned_##TYPE(char* ptr){ \
> + TYPE a_0, a_1; \
> + TYPE *arr = (TYPE*) ((uintptr_t)ptr & ~(2 * 8 * _Alignof(TYPE) - 1)); \
> + TYPE *a = arr+1; \
> + a_0 = a[0]; \
> + a_1 = a[1]; \
> + return a_0 + a_1; \
> +}
> +
> +#define LDP_TEST_ADJUST_ALIGNED(TYPE) \
> +TYPE ldp_aligned_adjust_##TYPE(char* ptr){ \
> + TYPE a_0, a_1, a_2, a_3, a_4; \
> + TYPE *arr = (TYPE*) ((uintptr_t)ptr & ~(2 * 8 * _Alignof(TYPE) - 1)); \
> + a_0 = arr[100]; \
> + a_1 = arr[101]; \
> + a_2 = arr[102]; \
> + a_3 = arr[103]; \
> + a_4 = arr[110]; \
> + return a_0 + a_1 + a_2 + a_3 + a_4; \
> +}
> +
> +#define LDP_TEST_ADJUST_UNALIGNED(TYPE) \
> +TYPE ldp_unaligned_adjust_##TYPE(char* ptr){ \
> + TYPE a_0, a_1, a_2, a_3, a_4; \
> + TYPE *arr = (TYPE*) ((uintptr_t)ptr & ~(2 * 8 * _Alignof(TYPE) - 1)); \
> + TYPE *a = arr+1; \
> + a_0 = a[100]; \
> + a_1 = a[101]; \
> + a_2 = a[102]; \
> + a_3 = a[103]; \
> + a_4 = a[110]; \
> + return a_0 + a_1 + a_2 + a_3 + a_4; \
> +}
> +
> +LDP_TEST_ALIGNED(int32_t);
> +LDP_TEST_ALIGNED(int64_t);
> +LDP_TEST_ALIGNED(v4si);
> +LDP_TEST_UNALIGNED(int32_t);
> +LDP_TEST_UNALIGNED(int64_t);
> +LDP_TEST_UNALIGNED(v4si);
> +LDP_TEST_ADJUST_ALIGNED(int32_t);
> +LDP_TEST_ADJUST_ALIGNED(int64_t);
> +LDP_TEST_ADJUST_UNALIGNED(int32_t);
> +LDP_TEST_ADJUST_UNALIGNED(int64_t);
> +
> +/* { dg-final { scan-assembler-times "ldp\tw\[0-9\]+, w\[0-9\]" 0 } } */
> +/* { dg-final { scan-assembler-times "ldp\tx\[0-9\]+, x\[0-9\]" 0 } } */
> +/* { dg-final { scan-assembler-times "ldp\tq\[0-9\]+, q\[0-9\]" 0 } } */
> +
> diff --git a/gcc/testsuite/gcc.target/aarch64/stp_aligned.c
> b/gcc/testsuite/gcc.target/aarch64/stp_aligned.c
> new file mode 100644
> index 00000000000..ab9c2f42dd3
> --- /dev/null
> +++ b/gcc/testsuite/gcc.target/aarch64/stp_aligned.c
> @@ -0,0 +1,60 @@
> +/* { dg-options "-O2 --param=aarch64-stp-policy=aligned -mcpu=generic" }
> */
> +
> +#include <stdlib.h>
> +#include <stdint.h>
> +
> +typedef int v4si __attribute__ ((vector_size (16)));
> +
> +#define STP_TEST_ALIGNED(TYPE) \
> +TYPE *stp_aligned_##TYPE(char* ptr, TYPE x){ \
> + TYPE *arr = (TYPE*) ((uintptr_t)ptr & ~(2 * 8 * _Alignof(TYPE) - 1)); \
> + arr[0] = x; \
> + arr[1] = x; \
> + return arr; \
> +}
> +
> +#define STP_TEST_UNALIGNED(TYPE) \
> +TYPE *stp_unaligned_##TYPE(char* ptr, TYPE x){ \
> + TYPE *arr = (TYPE*) ((uintptr_t)ptr & ~(2 * 8 * _Alignof(TYPE) - 1)); \
> + TYPE *a = arr+1; \
> + a[0] = x; \
> + a[1] = x; \
> + return a; \
> +}
> +
> +#define STP_TEST_ADJUST_ALIGNED(TYPE) \
> +TYPE *stp_aligned_adjust_##TYPE(char* ptr, TYPE x){ \
> + TYPE *arr = (TYPE*) ((uintptr_t)ptr & ~(2 * 8 * _Alignof(TYPE) - 1)); \
> + arr[100] = x; \
> + arr[101] = x; \
> + arr[102] = x; \
> + arr[103] = x; \
> + return arr; \
> +}
> +
> +#define STP_TEST_ADJUST_UNALIGNED(TYPE) \
> +TYPE *stp_unaligned_adjust_##TYPE(char* ptr, TYPE x){ \
> + TYPE *arr = (TYPE*) ((uintptr_t)ptr & ~(2 * 8 * _Alignof(TYPE) - 1)); \
> + TYPE *a = arr+1; \
> + a[100] = x; \
> + a[101] = x; \
> + a[102] = x; \
> + a[103] = x; \
> + return a; \
> +}
> +
> +STP_TEST_ALIGNED(int32_t);
> +STP_TEST_ALIGNED(int64_t);
> +STP_TEST_ALIGNED(v4si);
> +STP_TEST_UNALIGNED(int32_t);
> +STP_TEST_UNALIGNED(int64_t);
> +STP_TEST_UNALIGNED(v4si);
> +STP_TEST_ADJUST_ALIGNED(int32_t);
> +STP_TEST_ADJUST_ALIGNED(int64_t);
> +STP_TEST_ADJUST_UNALIGNED(int32_t);
> +STP_TEST_ADJUST_UNALIGNED(int64_t);
> +
> +/* { dg-final { scan-assembler-times "stp\tw\[0-9\]+, w\[0-9\]" 3 } } */
> +/* { dg-final { scan-assembler-times "stp\tx\[0-9\]+, x\[0-9\]" 3 } } */
> +/* { dg-final { scan-assembler-times "stp\tq\[0-9\]+, q\[0-9\]" 1 } } */
> +
> diff --git a/gcc/testsuite/gcc.target/aarch64/stp_always.c
> b/gcc/testsuite/gcc.target/aarch64/stp_always.c
> new file mode 100644
> index 00000000000..3787e239905
> --- /dev/null
> +++ b/gcc/testsuite/gcc.target/aarch64/stp_always.c
> @@ -0,0 +1,60 @@
> +/* { dg-options "-O2 --param=aarch64-stp-policy=always -mcpu=generic" } */
> +
> +#include <stdlib.h>
> +#include <stdint.h>
> +
> +typedef int v4si __attribute__ ((vector_size (16)));
> +
> +#define STP_TEST_ALIGNED(TYPE) \
> +TYPE *stp_aligned_##TYPE(char* ptr, TYPE x){ \
> + TYPE *arr = (TYPE*) ((uintptr_t)ptr & ~(2 * 8 * _Alignof(TYPE) - 1)); \
> + arr[0] = x; \
> + arr[1] = x; \
> + return arr; \
> +}
> +
> +#define STP_TEST_UNALIGNED(TYPE) \
> +TYPE *stp_unaligned_##TYPE(char* ptr, TYPE x){ \
> + TYPE *arr = (TYPE*) ((uintptr_t)ptr & ~(2 * 8 * _Alignof(TYPE) - 1)); \
> + TYPE *a = arr+1; \
> + a[0] = x; \
> + a[1] = x; \
> + return a; \
> +}
> +
> +#define STP_TEST_ADJUST_ALIGNED(TYPE) \
> +TYPE *stp_aligned_adjust_##TYPE(char* ptr, TYPE x){ \
> + TYPE *arr = (TYPE*) ((uintptr_t)ptr & ~(2 * 8 * _Alignof(TYPE) - 1)); \
> + arr[100] = x; \
> + arr[101] = x; \
> + arr[102] = x; \
> + arr[103] = x; \
> + return arr; \
> +}
> +
> +#define STP_TEST_ADJUST_UNALIGNED(TYPE) \
> +TYPE *stp_unaligned_adjust_##TYPE(char* ptr, TYPE x){ \
> + TYPE *arr = (TYPE*) ((uintptr_t)ptr & ~(2 * 8 * _Alignof(TYPE) - 1)); \
> + TYPE *a = arr+1; \
> + a[100] = x; \
> + a[101] = x; \
> + a[102] = x; \
> + a[103] = x; \
> + return a; \
> +}
> +
> +STP_TEST_ALIGNED(int32_t);
> +STP_TEST_ALIGNED(int64_t);
> +STP_TEST_ALIGNED(v4si);
> +STP_TEST_UNALIGNED(int32_t);
> +STP_TEST_UNALIGNED(int64_t);
> +STP_TEST_UNALIGNED(v4si);
> +STP_TEST_ADJUST_ALIGNED(int32_t);
> +STP_TEST_ADJUST_ALIGNED(int64_t);
> +STP_TEST_ADJUST_UNALIGNED(int32_t);
> +STP_TEST_ADJUST_UNALIGNED(int64_t);
> +
> +/* { dg-final { scan-assembler-times "stp\tw\[0-9\]+, w\[0-9\]" 6 } } */
> +/* { dg-final { scan-assembler-times "stp\tx\[0-9\]+, x\[0-9\]" 6 } } */
> +/* { dg-final { scan-assembler-times "stp\tq\[0-9\]+, q\[0-9\]" 2 } } */
> +
> diff --git a/gcc/testsuite/gcc.target/aarch64/stp_never.c
> b/gcc/testsuite/gcc.target/aarch64/stp_never.c
> new file mode 100644
> index 00000000000..f0f1ea53bbf
> --- /dev/null
> +++ b/gcc/testsuite/gcc.target/aarch64/stp_never.c
> @@ -0,0 +1,60 @@
> +/* { dg-options "-O2 --param=aarch64-stp-policy=never -mcpu=generic" } */
> +
> +#include <stdlib.h>
> +#include <stdint.h>
> +
> +typedef int v4si __attribute__ ((vector_size (16)));
> +
> +#define STP_TEST_ALIGNED(TYPE) \
> +TYPE *stp_aligned_##TYPE(char* ptr, TYPE x){ \
> + TYPE *arr = (TYPE*) ((uintptr_t)ptr & ~(2 * 8 * _Alignof(TYPE) - 1)); \
> + arr[0] = x; \
> + arr[1] = x; \
> + return arr; \
> +}
> +
> +#define STP_TEST_UNALIGNED(TYPE) \
> +TYPE *stp_unaligned_##TYPE(char* ptr, TYPE x){ \
> + TYPE *arr = (TYPE*) ((uintptr_t)ptr & ~(2 * 8 * _Alignof(TYPE) - 1)); \
> + TYPE *a = arr+1; \
> + a[0] = x; \
> + a[1] = x; \
> + return a; \
> +}
> +
> +#define STP_TEST_ADJUST_ALIGNED(TYPE) \
> +TYPE *stp_aligned_adjust_##TYPE(char* ptr, TYPE x){ \
> + TYPE *arr = (TYPE*) ((uintptr_t)ptr & ~(2 * 8 * _Alignof(TYPE) - 1)); \
> + arr[100] = x; \
> + arr[101] = x; \
> + arr[102] = x; \
> + arr[103] = x; \
> + return arr; \
> +}
> +
> +#define STP_TEST_ADJUST_UNALIGNED(TYPE) \
> +TYPE *stp_unaligned_adjust_##TYPE(char* ptr, TYPE x){ \
> + TYPE *arr = (TYPE*) ((uintptr_t)ptr & ~(2 * 8 * _Alignof(TYPE) - 1)); \
> + TYPE *a = arr+1; \
> + a[100] = x; \
> + a[101] = x; \
> + a[102] = x; \
> + a[103] = x; \
> + return a; \
> +}
> +
> +STP_TEST_ALIGNED(int32_t);
> +STP_TEST_ALIGNED(int64_t);
> +STP_TEST_ALIGNED(v4si);
> +STP_TEST_UNALIGNED(int32_t);
> +STP_TEST_UNALIGNED(int64_t);
> +STP_TEST_UNALIGNED(v4si);
> +STP_TEST_ADJUST_ALIGNED(int32_t);
> +STP_TEST_ADJUST_ALIGNED(int64_t);
> +STP_TEST_ADJUST_UNALIGNED(int32_t);
> +STP_TEST_ADJUST_UNALIGNED(int64_t);
> +
> +/* { dg-final { scan-assembler-times "stp\tw\[0-9\]+, w\[0-9\]" 0 } } */
> +/* { dg-final { scan-assembler-times "stp\tx\[0-9\]+, x\[0-9\]" 0 } } */
> +/* { dg-final { scan-assembler-times "stp\tq\[0-9\]+, q\[0-9\]" 0 } } */
> +
> --
> 2.40.1
