From d8c4c75cab618f21a7f3d4cdccc37f190d9de3c4 Mon Sep 17 00:00:00 2001 From: wilco Date: Wed, 11 Jan 2017 16:38:42 +0000 Subject: [PATCH] My previous change to the Cortex-A53 scheduler resulted in a 13% regression on a proprietary benchmark. This turned out to be due to non-optimal scheduling of int to float conversions. This patch separates int to FP transfers from int to float conversions based on experiments to determine the best schedule. As a result of these tweaks the performance of the benchmark improves by 20%. gcc/ * config/arm/cortex-a53.md: Add bypasses for cortex_a53_r2f_cvt. (cortex_a53_r2f): Only use for transfers. (cortex_a53_f2r): Likewise. (cortex_a53_r2f_cvt): Add reservation for conversions. (cortex_a53_f2r_cvt): Likewise. git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@244322 138bc75d-0d04-0410-961f-82ee72b054a4 --- gcc/ChangeLog | 9 +++++++++ gcc/config/arm/cortex-a53.md | 37 ++++++++++++++++++++++++++----------- 2 files changed, 35 insertions(+), 11 deletions(-) diff --git a/gcc/ChangeLog b/gcc/ChangeLog index bdf19ee6947..d0aae19cc41 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,12 @@ +2017-01-11 Wilco Dijkstra + + * config/arm/cortex-a53.md: Add bypasses for + cortex_a53_r2f_cvt. + (cortex_a53_r2f): Only use for transfers. + (cortex_a53_f2r): Likewise. + (cortex_a53_r2f_cvt): Add reservation for conversions. + (cortex_a53_f2r_cvt): Likewise. + 2017-01-11 Tamar Christina * config/arm/arm_neon.h: Add __artificial__ and gnu_inline diff --git a/gcc/config/arm/cortex-a53.md b/gcc/config/arm/cortex-a53.md index fbec5df1126..7cf5fc5a0cd 100644 --- a/gcc/config/arm/cortex-a53.md +++ b/gcc/config/arm/cortex-a53.md @@ -260,9 +260,18 @@ "cortex_a53_r2f") (define_bypass 1 "cortex_a53_mul, - cortex_a53_load*" + cortex_a53_load1, + cortex_a53_load2" "cortex_a53_r2f") +(define_bypass 2 "cortex_a53_alu*" + "cortex_a53_r2f_cvt") + +(define_bypass 3 "cortex_a53_mul, + cortex_a53_load1, + cortex_a53_load2" + "cortex_a53_r2f_cvt") + ;; Model flag forwarding to branches. (define_bypass 0 "cortex_a53_alu*,cortex_a53_shift*" @@ -522,19 +531,25 @@ ;; Floating-point to/from core transfers. ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; -(define_insn_reservation "cortex_a53_r2f" 6 +(define_insn_reservation "cortex_a53_r2f" 2 + (and (eq_attr "tune" "cortexa53") + (eq_attr "type" "f_mcr,f_mcrr")) + "cortex_a53_slot_any,cortex_a53_fp_alu") + +(define_insn_reservation "cortex_a53_f2r" 4 + (and (eq_attr "tune" "cortexa53") + (eq_attr "type" "f_mrc,f_mrrc")) + "cortex_a53_slot_any,cortex_a53_fp_alu") + +(define_insn_reservation "cortex_a53_r2f_cvt" 4 (and (eq_attr "tune" "cortexa53") - (eq_attr "type" "f_mcr,f_mcrr,f_cvti2f, - neon_from_gp, neon_from_gp_q")) - "cortex_a53_slot_any,cortex_a53_store, - nothing,cortex_a53_fp_alu") + (eq_attr "type" "f_cvti2f, neon_from_gp, neon_from_gp_q")) + "cortex_a53_slot_any,cortex_a53_fp_alu") -(define_insn_reservation "cortex_a53_f2r" 6 +(define_insn_reservation "cortex_a53_f2r_cvt" 5 (and (eq_attr "tune" "cortexa53") - (eq_attr "type" "f_mrc,f_mrrc,f_cvtf2i, - neon_to_gp, neon_to_gp_q")) - "cortex_a53_slot_any,cortex_a53_fp_alu, - nothing,cortex_a53_store") + (eq_attr "type" "f_cvtf2i, neon_to_gp, neon_to_gp_q")) + "cortex_a53_slot_any,cortex_a53_fp_alu") ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;; ;; Floating-point flag transfer. -- 2.11.4.GIT