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;; Scheduling description for the Xilinx PowerPC 405 APU Floating Point Unit.

;; Copyright (C) 2008 Free Software Foundation, Inc.

;; Contributed by Michael Eager (eager@eagercon.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

;; .

;;----------------------------------------------------

;; Xilinx APU FPU Pipeline Description

;;

;;  - attr 'type' and 'fp_type' should definitely

;;    be cleaned up at some point in the future.

;;    ddiv,sdiv,dmul,smul etc are quite confusing.

;;    Should use consistent fp* attrs. 'fp_type'

;;    should also go away, leaving us only with 'fp'

;;

;;----------------------------------------------------

;; -------------------------------------------------------------------------

;; Latencies

;; Latest latency figures (all in FCB cycles). PowerPC to FPU frequency ratio

;; assumed to be 1/2. (most common deployment)

;; Add 2 PPC cycles for (register file access + wb) and 2 PPC cycles

;; for issue (from PPC)

;;                          SP          DP

;; Loads:                    4           6

;; Stores:                   1           2      (from availability of data)

;; Move/Abs/Neg:             1           1

;; Add/Subtract:             5           7

;; Multiply:                 4          11

;; Multiply-add:            10          19

;; Convert (any):            4           6

;; Divide/Sqrt:             27          56

;; Compares:                 1           2

;;

;; bypasses needed for forwarding capability of the FPU.

;; Add this at some future time.

;; -------------------------------------------------------------------------

(define_automaton "Xfpu")

(define_cpu_unit "Xfpu_issue,Xfpu_addsub,Xfpu_mul,Xfpu_div,Xfpu_sqrt" "Xfpu")

(define_insn_reservation "fp-default" 2

  (and (and

        (eq_attr "type" "fp")

        (eq_attr "fp_type" "fp_default"))

       (eq_attr "cpu" "ppc405"))

  "Xfpu_issue*2")

(define_insn_reservation "fp-compare" 6

  (and (eq_attr "type" "fpcompare")                     ;; Inconsistent naming

       (eq_attr "cpu" "ppc405"))

  "Xfpu_issue*2,Xfpu_addsub")

(define_insn_reservation "fp-addsub-s" 14

  (and (and

        (eq_attr "type" "fp")

        (eq_attr "fp_type" "fp_addsub_s"))

       (eq_attr "cpu" "ppc405"))

  "Xfpu_issue*2,Xfpu_addsub")

(define_insn_reservation "fp-addsub-d" 18

  (and (and

        (eq_attr "type" "fp")

        (eq_attr "fp_type" "fp_addsub_d"))

       (eq_attr "cpu" "ppc405"))

  "Xfpu_issue*2,Xfpu_addsub")

(define_insn_reservation "fp-mul-s" 12

  (and (and

        (eq_attr "type" "fp")

        (eq_attr "fp_type" "fp_mul_s"))

       (eq_attr "cpu" "ppc405"))

  "Xfpu_issue*2,Xfpu_mul")

(define_insn_reservation "fp-mul-d" 16    ;; Actually 28. Long latencies are killing the automaton formation. Need to figure out why.

  (and (and

        (eq_attr "type" "fp")

        (eq_attr "fp_type" "fp_mul_d"))

       (eq_attr "cpu" "ppc405"))

  "Xfpu_issue*2,Xfpu_mul")

(define_insn_reservation "fp-div-s" 24                   ;; Actually 34

   (and (eq_attr "type" "sdiv")                          ;; Inconsistent attr naming

        (eq_attr "cpu" "ppc405"))

   "Xfpu_issue*2,Xfpu_div*10")                           ;; Unpipelined

(define_insn_reservation "fp-div-d" 34                   ;; Actually 116

  (and (eq_attr "type" "ddiv")

       (eq_attr "cpu" "ppc405"))                         ;; Inconsistent attr naming

  "Xfpu_issue*2,Xfpu_div*10")                            ;; Unpipelined

(define_insn_reservation "fp-maddsub-s" 24

  (and (and

        (eq_attr "type" "fp")

        (eq_attr "fp_type" "fp_maddsub_s"))

       (eq_attr "cpu" "ppc405"))

  "Xfpu_issue*2,Xfpu_mul,nothing*7,Xfpu_addsub")

(define_insn_reservation "fp-maddsub-d" 34              ;; Actually 42

  (and (and

        (eq_attr "type" "dmul")                         ;; Inconsistent attr naming

        (eq_attr "fp_type" "fp_maddsub_d"))

       (eq_attr "cpu" "ppc405"))

  "Xfpu_issue*2,Xfpu_mul,nothing*7,Xfpu_addsub")

(define_insn_reservation "fp-load" 10                   ;; FIXME. Is double/single precision the same ?

  (and (eq_attr "type" "fpload, fpload_ux, fpload_u")

       (eq_attr "cpu" "ppc405"))

  "Xfpu_issue*10")

(define_insn_reservation "fp-store" 4

  (and (eq_attr "type" "fpstore, fpstore_ux, fpstore_u")

       (eq_attr "cpu" "ppc405"))

  "Xfpu_issue*4")

(define_insn_reservation "fp-sqrt-s" 24         ;; Actually 56

  (and (eq_attr "type" "ssqrt")

       (eq_attr "cpu" "ppc405"))

  "Xfpu_issue*2,Xfpu_sqrt*10")                  ;; Unpipelined

(define_insn_reservation "fp-sqrt-d" 34         ;; Actually 116

  (and (eq_attr "type" "dsqrt")

       (eq_attr "cpu" "ppc405"))

  "Xfpu_issue*2,Xfpu_sqrt*10")                  ;; Unpipelined