1/* libgcc1 routines for 68000 w/o floating-point hardware.
2 Copyright (C) 1994, 1996, 1997, 1998 Free Software Foundation, Inc.
3
4This file is part of GNU CC.
5
6GNU CC is free software; you can redistribute it and/or modify it
7under the terms of the GNU General Public License as published by the
8Free Software Foundation; either version 2, or (at your option) any
9later version.
10
11In addition to the permissions in the GNU General Public License, the
12Free Software Foundation gives you unlimited permission to link the
13compiled version of this file with other programs, and to distribute
14those programs without any restriction coming from the use of this
15file. (The General Public License restrictions do apply in other
16respects; for example, they cover modification of the file, and
17distribution when not linked into another program.)
18
19This file is distributed in the hope that it will be useful, but
20WITHOUT ANY WARRANTY; without even the implied warranty of
21MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
22General Public License for more details. */
23
24/* As a special exception, if you link this library with files
25 compiled with GCC to produce an executable, this does not cause
26 the resulting executable to be covered by the GNU General Public License.
27 This exception does not however invalidate any other reasons why
28 the executable file might be covered by the GNU General Public License. */
29
30/* Use this one for any 680x0; assumes no floating point hardware.
31 The trailing " '" appearing on some lines is for ANSI preprocessors. Yuk.
32 Some of this code comes from MINIX, via the folks at ericsson.
33 D. V. Henkel-Wallace (gumby@cygnus.com) Fete Bastille, 1992
34*/
35
36#include <linux/export.h>
37
38/* These are predefined by new versions of GNU cpp. */
39
40#ifndef __USER_LABEL_PREFIX__
41#define __USER_LABEL_PREFIX__ _
42#endif
43
44#ifndef __REGISTER_PREFIX__
45#define __REGISTER_PREFIX__
46#endif
47
48#ifndef __IMMEDIATE_PREFIX__
49#define __IMMEDIATE_PREFIX__ #
50#endif
51
52/* ANSI concatenation macros. */
53
54#define CONCAT1(a, b) CONCAT2(a, b)
55#define CONCAT2(a, b) a ## b
56
57/* Use the right prefix for global labels. */
58
59#define SYM(x) CONCAT1 (__USER_LABEL_PREFIX__, x)
60
61/* Use the right prefix for registers. */
62
63#define REG(x) CONCAT1 (__REGISTER_PREFIX__, x)
64
65/* Use the right prefix for immediate values. */
66
67#define IMM(x) CONCAT1 (__IMMEDIATE_PREFIX__, x)
68
69#define d0 REG (d0)
70#define d1 REG (d1)
71#define d2 REG (d2)
72#define d3 REG (d3)
73#define d4 REG (d4)
74#define d5 REG (d5)
75#define d6 REG (d6)
76#define d7 REG (d7)
77#define a0 REG (a0)
78#define a1 REG (a1)
79#define a2 REG (a2)
80#define a3 REG (a3)
81#define a4 REG (a4)
82#define a5 REG (a5)
83#define a6 REG (a6)
84#define fp REG (fp)
85#define sp REG (sp)
86
87 .text
88 .proc
89 .globl SYM (__divsi3)
90SYM (__divsi3):
91 movel d2, sp@-
92
93 moveq IMM (1), d2 /* sign of result stored in d2 (=1 or =-1) */
94 movel sp@(12), d1 /* d1 = divisor */
95 jpl L1
96 negl d1
97#if !(defined(__mcf5200__) || defined(__mcoldfire__))
98 negb d2 /* change sign because divisor <0 */
99#else
100 negl d2 /* change sign because divisor <0 */
101#endif
102L1: movel sp@(8), d0 /* d0 = dividend */
103 jpl L2
104 negl d0
105#if !(defined(__mcf5200__) || defined(__mcoldfire__))
106 negb d2
107#else
108 negl d2
109#endif
110
111L2: movel d1, sp@-
112 movel d0, sp@-
113 jbsr SYM (__udivsi3) /* divide abs(dividend) by abs(divisor) */
114 addql IMM (8), sp
115
116 tstb d2
117 jpl L3
118 negl d0
119
120L3: movel sp@+, d2
121 rts
122
123 EXPORT_SYMBOL(__divsi3)
124

source code of linux/arch/m68k/lib/divsi3.S