blob: 6f2ca18c3f98b07005f4d5e0ec38bca9fc66c279 [file] [log] [blame]
;; Copyright 2010 Free Software Foundation, Inc.
;; Contributed by Bernd Schmidt <>.
;; This program 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 2 of the License, or
;; (at your option) any later version.
;; This program is distributed in the hope that it will be useful,
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;; GNU General Public License for more details.
;; You should have received a copy of the GNU General Public License
;; along with this program; if not, write to the Free Software
;; Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
#include <linux/linkage.h>
;; ABI considerations for the divide functions
;; The following registers are call-used:
;; __c6xabi_divi A0,A1,A2,A4,A6,B0,B1,B2,B4,B5
;; __c6xabi_divu A0,A1,A2,A4,A6,B0,B1,B2,B4
;; __c6xabi_remi A1,A2,A4,A5,A6,B0,B1,B2,B4
;; __c6xabi_remu A1,A4,A5,A7,B0,B1,B2,B4
;; In our implementation, divu and remu are leaf functions,
;; while both divi and remi call into divu.
;; A0 is not clobbered by any of the functions.
;; divu does not clobber B2 either, which is taken advantage of
;; in remi.
;; divi uses B5 to hold the original return address during
;; the call to divu.
;; remi uses B2 and A5 to hold the input values during the
;; call to divu. It stores B3 in on the stack.
stw .d2t2 B3, *B15--[2]
|| cmpgt .l1 0, A4, A1
|| cmpgt .l2 0, B4, B2
|| mv .s1 A4, A5
|| call .s2 __c6xabi_divu
[A1] neg .l1 A4, A4
|| [B2] neg .l2 B4, B4
|| xor .s2x B2, A1, B0
|| mv .d2 B4, B2
[B0] addkpc .s2 _divu_ret_1, B3, 1
[!B0] addkpc .s2 _divu_ret_2, B3, 1
nop 2
neg .l1 A4, A4
ldw .d2t2 *++B15[2], B3
mpy32 .m1x A4, B2, A6
nop 3
ret .s2 B3
sub .l1 A5, A6, A4
nop 4