;; DFA-based pipeline descriptions for MIPS32 4K processor family ;; Contributed by Nigel Stephens (nigel@mips.com) ;; and David Ung (davidu@mips.com) ;; ;; References: ;; “MIPS32 4K Processor Core Family Software User's Manual, ;; Doc no: MD00016, Rev 1.18, Nov 15, 2004.” ;; ;; 4Kc - pipelined multiplier and translation lookaside buffer (TLB) ;; 4km - pipelined multiplier and block address translator (BAT) ;; 4kp - non-pipelined multiplier and block address translator (BAT) ;; ;; Copyright (C) 2005-2021 Free Software Foundation, Inc. ;; ;; 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 “r4k_cpu, r4k_mdu”)

;; Integer execution unit. (define_cpu_unit “r4k_ixu_arith” “r4k_cpu”) (define_cpu_unit “r4k_ixu_mpydiv” “r4k_mdu”)

(define_insn_reservation “r4k_int_load” 2 (and (eq_attr “cpu” “4kc,4kp”) (eq_attr “type” “load”)) “r4k_ixu_arith”)

(define_insn_reservation “r4k_int_prefetch” 1 (and (eq_attr “cpu” “4kc,4kp”) (eq_attr “type” “prefetch”)) “r4k_ixu_arith”)

(define_insn_reservation “r4k_int_store” 1 (and (eq_attr “cpu” “4kc,4kp”) (eq_attr “type” “store”)) “r4k_ixu_arith”)

;; 4Kc/4Km ;; unsigned divide - 8/16/24/32-bit operand have latencies 9/17/25/33 ;; signed divide - 8/16/24/32-bit operand have latencies 10/18/26/34 (define_insn_reservation “r4k_idiv_4kc” 34 (and (eq_attr “cpu” “4kc”) (and (eq_attr “type” “idiv”) (eq_attr “mode” “!DI”))) “r4k_ixu_arith+(r4k_ixu_mpydiv*34)”)

;; 4Kp ;; unsigned divide - 33 ;; signed divide - 33-35 (define_insn_reservation “r4k_idiv_4kp” 35 (and (eq_attr “cpu” “4kp”) (and (eq_attr “type” “idiv”) (eq_attr “mode” “!DI”))) “r4k_ixu_arith+(r4k_ixu_mpydiv*35)”)

;; 4Kc/4Km fast 32x32 multiply ;; 16x32 is faster, but there's no way to detect this (define_insn_reservation “r4k_mult_4kc” 2 (and (eq_attr “cpu” “4kc”) (and (eq_attr “type” “imul,imadd”) (eq_attr “mode” “SI”))) “r4k_ixu_arith+(r4k_ixu_mpydiv*2)”)

;; 4Kc/4Km MUL has 2 cycle latency, but has the special property that it will ;; stall the integer unit pipeline. MUL 16x16 or 32x16 forces 1 cycle stall, ;; while MUL 32x32 forces 2 cycle stall. If next insn use the result, an ;; additional stall is forced. (define_insn_reservation “r4k_mul_4kc” 4 (and (eq_attr “cpu” “4kc”) (and (eq_attr “type” “imul3”) (eq_attr “mode” “SI”))) “(r4k_ixu_arith+r4k_ixu_mpydiv)*3”)

;; 4Kp slow iterative 2-op MULT ;; Latency of 32 if next insn is MADD/MSUB,MFHI/MFLO. ;; Repeat rate of 33 cycles. (define_insn_reservation “r4k_mult_4kp” 32 (and (eq_attr “cpu” “4kp”) (and (eq_attr “type” “imul”) (eq_attr “mode” “SI”))) “r4k_ixu_arith+(r4k_ixu_mpydiv*32)”)

;; 4Kp slow iterative 3-op MUL ;; Latency of 32 cycles, but stalls the whole pipeline until complete. (define_insn_reservation “r4k_mul_4kp” 32 (and (eq_attr “cpu” “4kp”) (and (eq_attr “type” “imul3”) (eq_attr “mode” “SI”))) “(r4k_ixu_arith+r4k_ixu_mpydiv)*32”)

;; 4Kp slow iterative MADD ;; Latency of 34 if next use insn is MADD/MSUB,MFHI/MFLO. ;; Repeat rate of 35 cycles. (define_insn_reservation “r4k_madd_4kp” 34 (and (eq_attr “cpu” “4kp”) (and (eq_attr “type” “imadd”) (eq_attr “mode” “SI”))) “r4k_ixu_arith+(r4k_ixu_mpydiv*34)”)

;; Move to HI/LO -> MADD/MSUB,MFHI/MFLO has a 1 cycle latency. (define_insn_reservation “r4k_int_mthilo” 1 (and (eq_attr “cpu” “4kc,4kp”) (eq_attr “type” “mthi,mtlo”)) “r4k_ixu_arith+r4k_ixu_mpydiv”)

;; Move from HI/LO -> integer operation has a 2 cycle latency. (define_insn_reservation “r4k_int_mfhilo” 2 (and (eq_attr “cpu” “4kc,4kp”) (eq_attr “type” “mfhi,mflo”)) “r4k_ixu_arith+r4k_ixu_mpydiv”)

;; All other integer insns. (define_insn_reservation “r4k_int_alu” 1 (and (eq_attr “cpu” “4kc,4kp”) (eq_attr “type” “arith,condmove,const,logical,move,nop,shift,signext,slt”)) “r4k_ixu_arith”)

(define_insn_reservation “r4k_int_branch” 1 (and (eq_attr “cpu” “4kc,4kp”) (eq_attr “type” “branch”)) “r4k_ixu_arith”)

(define_insn_reservation “r4k_int_jump_4k” 1 (and (eq_attr “cpu” “4kc,4kp”) (eq_attr “type” “jump,call”)) “r4k_ixu_arith”)

;; mfcx/mtcx - non FPU ;; (Disabled until we add cop0 support) ;; (define_insn_reservation “r4k_int_cop” 2 ;; (and (eq_attr “cpu” “4kc,4kp”) ;; (eq_attr “type” “cop0”)) ;; “r4k_ixu_arith”)

;; Unknown or multi - single issue (define_insn_reservation “r4k_unknown” 1 (and (eq_attr “cpu” “4kc,4kp”) (eq_attr “type” “unknown,multi,atomic,syncloop”)) “r4k_ixu_arith+r4k_ixu_mpydiv”)