From 9d29ae83ed27a06cdd729cd7f0cceb12c28b91dc Mon Sep 17 00:00:00 2001 From: Wilco Dijkstra Date: Fri, 5 May 2017 09:40:01 +0000 Subject: [PATCH] Code scheduling for Cortex-A53 isn't as good as it could be. Code scheduling for Cortex-A53 isn't as good as it could be. It turns out code runs faster overall if we place loads and stores with a dependency closer together. To achieve this effect, this patch adds a bypass between cortex_a53_load1 and cortex_a53_load*/cortex_a53_store* if the result of an earlier load is used in an address calculation. This significantly improved benchmark scores in a proprietary benchmark suite. gcc/ * config/arm/aarch-common.c (arm_early_load_addr_dep_ptr): New function. (arm_early_store_addr_dep_ptr): Likewise. * config/arm/aarch-common-protos.h (arm_early_load_addr_dep_ptr): Add prototype. (arm_early_store_addr_dep_ptr): Likewise. * config/arm/cortex-a53.md: Add new bypasses. From-SVN: r247631 --- gcc/ChangeLog | 10 ++++++++ gcc/config/arm/aarch-common-protos.h | 2 ++ gcc/config/arm/aarch-common.c | 36 ++++++++++++++++++++++++++++ gcc/config/arm/cortex-a53.md | 10 ++++++++ 4 files changed, 58 insertions(+) diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 44df0d7ecdd..910658a970b 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,13 @@ +2017-05-05 Wilco Dijkstra + + * config/arm/aarch-common.c (arm_early_load_addr_dep_ptr): + New function. + (arm_early_store_addr_dep_ptr): Likewise. + * config/arm/aarch-common-protos.h + (arm_early_load_addr_dep_ptr): Add prototype. + (arm_early_store_addr_dep_ptr): Likewise. + * config/arm/cortex-a53.md: Add new bypasses. + 2017-05-05 Jakub Jelinek * tree.c (next_type_uid): Change type to unsigned. diff --git a/gcc/config/arm/aarch-common-protos.h b/gcc/config/arm/aarch-common-protos.h index 7c2bb4c2ed9..35d2d96c9fd 100644 --- a/gcc/config/arm/aarch-common-protos.h +++ b/gcc/config/arm/aarch-common-protos.h @@ -30,7 +30,9 @@ extern bool aarch_rev16_p (rtx); extern bool aarch_rev16_shleft_mask_imm_p (rtx, machine_mode); extern bool aarch_rev16_shright_mask_imm_p (rtx, machine_mode); extern int arm_early_load_addr_dep (rtx, rtx); +extern int arm_early_load_addr_dep_ptr (rtx, rtx); extern int arm_early_store_addr_dep (rtx, rtx); +extern int arm_early_store_addr_dep_ptr (rtx, rtx); extern int arm_mac_accumulator_is_mul_result (rtx, rtx); extern int arm_mac_accumulator_is_result (rtx, rtx); extern int arm_no_early_alu_shift_dep (rtx, rtx); diff --git a/gcc/config/arm/aarch-common.c b/gcc/config/arm/aarch-common.c index 742d2ff4c7b..6a04711335d 100644 --- a/gcc/config/arm/aarch-common.c +++ b/gcc/config/arm/aarch-common.c @@ -241,6 +241,24 @@ arm_early_load_addr_dep (rtx producer, rtx consumer) return reg_overlap_mentioned_p (value, addr); } +/* Return nonzero if the CONSUMER instruction (a load) does need + a Pmode PRODUCER's value to calculate the address. */ + +int +arm_early_load_addr_dep_ptr (rtx producer, rtx consumer) +{ + rtx value = arm_find_sub_rtx_with_code (PATTERN (producer), SET, false); + rtx addr = arm_find_sub_rtx_with_code (PATTERN (consumer), SET, false); + + if (!value || !addr || !MEM_P (SET_SRC (value))) + return 0; + + value = SET_DEST (value); + addr = SET_SRC (addr); + + return GET_MODE (value) == Pmode && reg_overlap_mentioned_p (value, addr); +} + /* Return nonzero if the CONSUMER instruction (an ALU op) does not have an early register shift value or amount dependency on the result of PRODUCER. */ @@ -336,6 +354,24 @@ arm_early_store_addr_dep (rtx producer, rtx consumer) return !arm_no_early_store_addr_dep (producer, consumer); } +/* Return nonzero if the CONSUMER instruction (a store) does need + a Pmode PRODUCER's value to calculate the address. */ + +int +arm_early_store_addr_dep_ptr (rtx producer, rtx consumer) +{ + rtx value = arm_find_sub_rtx_with_code (PATTERN (producer), SET, false); + rtx addr = arm_find_sub_rtx_with_code (PATTERN (consumer), SET, false); + + if (!value || !addr || !MEM_P (SET_SRC (value))) + return 0; + + value = SET_DEST (value); + addr = SET_DEST (addr); + + return GET_MODE (value) == Pmode && reg_overlap_mentioned_p (value, addr); +} + /* Return non-zero iff the consumer (a multiply-accumulate or a multiple-subtract instruction) has an accumulator dependency on the result of the producer and no other dependency on that result. It diff --git a/gcc/config/arm/cortex-a53.md b/gcc/config/arm/cortex-a53.md index 7cf5fc5a0cd..b7e0c9257f7 100644 --- a/gcc/config/arm/cortex-a53.md +++ b/gcc/config/arm/cortex-a53.md @@ -254,6 +254,16 @@ "cortex_a53_store*" "arm_no_early_store_addr_dep") +;; Model a bypass for load to load/store address. + +(define_bypass 3 "cortex_a53_load1" + "cortex_a53_load*" + "arm_early_load_addr_dep_ptr") + +(define_bypass 3 "cortex_a53_load1" + "cortex_a53_store*" + "arm_early_store_addr_dep_ptr") + ;; Model a GP->FP register move as similar to stores. (define_bypass 0 "cortex_a53_alu*,cortex_a53_shift*" -- 2.30.2