;; ARM Cortex-A15 pipeline description ;; Copyright (C) 2011-2020 Free Software Foundation, Inc. ;; ;; Written by Matthew Gretton-Dann matthew.gretton-dann@arm.com
;; 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/.
(define_automaton “cortex_a15”)
;; The Cortex-A15 core is modelled as a triple issue pipeline that has ;; the following dispatch units. ;; 1. Two pipelines for simple integer operations: SX1, SX2 ;; 2. Individual units for Neon and FP operations as in cortex-a15-neon.md ;; 3. One pipeline for branch operations: BX ;; 4. One pipeline for integer multiply and divide operations: MX ;; 5. Two pipelines for load and store operations: LS1, LS2 ;; ;; We can issue into three pipelines per-cycle. ;; ;; We assume that where we have unit pairs xx1 is always filled before xx2.
;; The three issue units (define_cpu_unit “ca15_i0, ca15_i1, ca15_i2” “cortex_a15”)
(define_reservation “ca15_issue1” “(ca15_i0|ca15_i1|ca15_i2)”) (define_reservation “ca15_issue2” “((ca15_i0+ca15_i1)|(ca15_i1+ca15_i2))”) (define_reservation “ca15_issue3” “(ca15_i0+ca15_i1+ca15_i2)”) (final_presence_set “ca15_i1” “ca15_i0”) (final_presence_set “ca15_i2” “ca15_i1”)
;; The main dispatch units (define_cpu_unit “ca15_sx1, ca15_sx2” “cortex_a15”) (define_cpu_unit “ca15_ls1, ca15_ls2” “cortex_a15”) (define_cpu_unit “ca15_bx, ca15_mx” “cortex_a15”)
(define_reservation “ca15_ls” “(ca15_ls1|ca15_ls2)”)
;; The extended load-store pipeline (define_cpu_unit “ca15_ldr, ca15_str” “cortex_a15”)
;; The extended ALU pipeline (define_cpu_unit “ca15_sx1_alu, ca15_sx1_shf, ca15_sx1_sat” “cortex_a15”) (define_cpu_unit “ca15_sx2_alu, ca15_sx2_shf, ca15_sx2_sat” “cortex_a15”)
;; Simple Execution Unit: ;; ;; Simple ALU without shift (define_insn_reservation “cortex_a15_alu” 2 (and (eq_attr “tune” “cortexa15”) (eq_attr “type” “alu_imm,alus_imm,logic_imm,logics_imm,
alu_sreg,alus_sreg,logic_reg,logics_reg,
adc_imm,adcs_imm,adc_reg,adcs_reg,
adr,bfm,clz,rbit,rev,alu_dsp_reg,
shift_imm,shift_reg,
mov_imm,mov_reg,
mvn_imm,mvn_reg,
mrs,multiple”)) “ca15_issue1,(ca15_sx1,ca15_sx1_alu)|(ca15_sx2,ca15_sx2_alu)”)
;; ALU ops with immediate shift ;; crc is also included here so that appropriate scheduling of CRC32 ARMv8-A ;; instructions can be performed when tuning for the Cortex-A57 since that ;; core reuses the Cortex-A15 pipeline description for the moment. (define_insn_reservation “cortex_a15_alu_shift” 3 (and (eq_attr “tune” “cortexa15”) (eq_attr “type” “extend,
alu_shift_imm,alus_shift_imm,
crc,logic_shift_imm,logics_shift_imm,
mov_shift,mvn_shift”)) “ca15_issue1,(ca15_sx1,ca15_sx1+ca15_sx1_shf,ca15_sx1_alu)
|(ca15_sx2,ca15_sx2+ca15_sx2_shf,ca15_sx2_alu)”)
;; ALU ops with register controlled shift (define_insn_reservation “cortex_a15_alu_shift_reg” 3 (and (eq_attr “tune” “cortexa15”) (eq_attr “type” “alu_shift_reg,alus_shift_reg,
logic_shift_reg,logics_shift_reg,
mov_shift_reg,mvn_shift_reg”)) “(ca15_issue2,ca15_sx1+ca15_sx2,ca15_sx1_shf,ca15_sx2_alu)
|(ca15_issue1,(ca15_issue1+ca15_sx2,ca15_sx1+ca15_sx2_shf)
|(ca15_issue1+ca15_sx1,ca15_sx1+ca15_sx1_shf),ca15_sx1_alu)”)
;; Multiply Execution Unit: ;; ;; 32-bit multiplies (define_insn_reservation “cortex_a15_mult32” 3 (and (eq_attr “tune” “cortexa15”) (eq_attr “mul32” “yes”)) “ca15_issue1,ca15_mx”)
;; 64-bit multiplies (define_insn_reservation “cortex_a15_mult64” 4 (and (eq_attr “tune” “cortexa15”) (eq_attr “widen_mul64” “yes”)) “ca15_issue1,ca15_mx*2”)
;; Integer divide (define_insn_reservation “cortex_a15_udiv” 9 (and (eq_attr “tune” “cortexa15”) (eq_attr “type” “udiv”)) “ca15_issue1,ca15_mx”)
(define_insn_reservation “cortex_a15_sdiv” 10 (and (eq_attr “tune” “cortexa15”) (eq_attr “type” “sdiv”)) “ca15_issue1,ca15_mx”)
;; Block all issue pipes for a cycle (define_insn_reservation “cortex_a15_block” 1 (and (eq_attr “tune” “cortexa15”) (eq_attr “type” “block”)) “ca15_issue3”)
;; Branch execution Unit ;; ;; Branches take one issue slot. ;; No latency as there is no result (define_insn_reservation “cortex_a15_branch” 0 (and (eq_attr “tune” “cortexa15”) (eq_attr “type” “branch”)) “ca15_issue1,ca15_bx”)
;; Load-store execution Unit ;; ;; Loads of up to two words. (define_insn_reservation “cortex_a15_load1” 4 (and (eq_attr “tune” “cortexa15”) (eq_attr “type” “load_byte,load_4,load_8”)) “ca15_issue1,ca15_ls,ca15_ldr,nothing”)
;; Loads of three or four words. (define_insn_reservation “cortex_a15_load3” 5 (and (eq_attr “tune” “cortexa15”) (eq_attr “type” “load_12,load_16”)) “ca15_issue2,ca15_ls1+ca15_ls2,ca15_ldr,ca15_ldr,nothing”)
;; Stores of up to two words. (define_insn_reservation “cortex_a15_store1” 0 (and (eq_attr “tune” “cortexa15”) (eq_attr “type” “store_4,store_8”)) “ca15_issue1,ca15_ls,ca15_str”)
;; Stores of three or four words. (define_insn_reservation “cortex_a15_store3” 0 (and (eq_attr “tune” “cortexa15”) (eq_attr “type” “store_12,store_16”)) “ca15_issue2,ca15_ls1+ca15_ls2,ca15_str,ca15_str”)
;; We include Neon.md here to ensure that the branch can block the Neon units. (include “../arm/cortex-a15-neon.md”)
;; We lie with calls. They take up all issue slots, and form a block in the ;; pipeline. The result however is available the next cycle. (define_insn_reservation “cortex_a15_call” 1 (and (eq_attr “tune” “cortexa15”) (eq_attr “type” “call”)) “ca15_issue3,
ca15_sx1+ca15_sx2+ca15_bx+ca15_mx+ca15_cx_ij+ca15_cx_ik+ca15_ls1+ca15_ls2+
ca15_cx_imac1+ca15_cx_ialu1+ca15_cx_ialu2+ca15_cx_ishf+
ca15_cx_acc+ca15_cx_fmul1+ca15_cx_fmul2+ca15_cx_fmul3+ca15_cx_fmul4+
ca15_cx_falu1+ca15_cx_falu2+ca15_cx_falu3+ca15_cx_falu4+ca15_cx_vfp_i,
ca15_sx1_alu+ca15_sx1_shf+ca15_sx1_sat+ca15_sx2_alu+
ca15_sx2_shf+ca15_sx2_sat+ca15_ldr+ca15_str”)
;; Simple execution unit bypasses (define_bypass 1 “cortex_a15_alu” “cortex_a15_alu,cortex_a15_alu_shift,cortex_a15_alu_shift_reg”) (define_bypass 2 “cortex_a15_alu_shift” “cortex_a15_alu,cortex_a15_alu_shift,cortex_a15_alu_shift_reg”) (define_bypass 2 “cortex_a15_alu_shift_reg” “cortex_a15_alu,cortex_a15_alu_shift,cortex_a15_alu_shift_reg”) (define_bypass 1 “cortex_a15_alu” “cortex_a15_load1,cortex_a15_load3”) (define_bypass 2 “cortex_a15_alu_shift” “cortex_a15_load1,cortex_a15_load3”) (define_bypass 2 “cortex_a15_alu_shift_reg” “cortex_a15_load1,cortex_a15_load3”)