1;; Copyright 2010 Free Software Foundation, Inc. 2;; Contributed by Bernd Schmidt <bernds@codesourcery.com>. 3;; 4;; This program is free software; you can redistribute it and/or modify 5;; it under the terms of the GNU General Public License as published by 6;; the Free Software Foundation; either version 2 of the License, or 7;; (at your option) any later version. 8;; 9;; This program is distributed in the hope that it will be useful, 10;; but WITHOUT ANY WARRANTY; without even the implied warranty of 11;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 12;; GNU General Public License for more details. 13;; 14;; You should have received a copy of the GNU General Public License 15;; along with this program; if not, write to the Free Software 16;; Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. 17 18#include <linux/linkage.h> 19 20 ;; ABI considerations for the divide functions 21 ;; The following registers are call-used: 22 ;; __c6xabi_divi A0,A1,A2,A4,A6,B0,B1,B2,B4,B5 23 ;; __c6xabi_divu A0,A1,A2,A4,A6,B0,B1,B2,B4 24 ;; __c6xabi_remi A1,A2,A4,A5,A6,B0,B1,B2,B4 25 ;; __c6xabi_remu A1,A4,A5,A7,B0,B1,B2,B4 26 ;; 27 ;; In our implementation, divu and remu are leaf functions, 28 ;; while both divi and remi call into divu. 29 ;; A0 is not clobbered by any of the functions. 30 ;; divu does not clobber B2 either, which is taken advantage of 31 ;; in remi. 32 ;; divi uses B5 to hold the original return address during 33 ;; the call to divu. 34 ;; remi uses B2 and A5 to hold the input values during the 35 ;; call to divu. It stores B3 in on the stack. 36 37 .text 38 39ENTRY(__c6xabi_remi) 40 stw .d2t2 B3, *B15--[2] 41|| cmpgt .l1 0, A4, A1 42|| cmpgt .l2 0, B4, B2 43|| mv .s1 A4, A5 44|| call .s2 __c6xabi_divu 45 46 [A1] neg .l1 A4, A4 47|| [B2] neg .l2 B4, B4 48|| xor .s2x B2, A1, B0 49|| mv .d2 B4, B2 50 51 [B0] addkpc .s2 _divu_ret_1, B3, 1 52 [!B0] addkpc .s2 _divu_ret_2, B3, 1 53 nop 2 54_divu_ret_1: 55 neg .l1 A4, A4 56_divu_ret_2: 57 ldw .d2t2 *++B15[2], B3 58 59 mpy32 .m1x A4, B2, A6 60 nop 3 61 ret .s2 B3 62 sub .l1 A5, A6, A4 63 nop 4 64ENDPROC(__c6xabi_remi) 65