xref: /linux/arch/m68k/lib/divsi3.S (revision bb9707077b4ee5f77bc9939b057ff8a0d410296f)
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/* These are predefined by new versions of GNU cpp.  */
37
38#ifndef __USER_LABEL_PREFIX__
39#define __USER_LABEL_PREFIX__ _
40#endif
41
42#ifndef __REGISTER_PREFIX__
43#define __REGISTER_PREFIX__
44#endif
45
46#ifndef __IMMEDIATE_PREFIX__
47#define __IMMEDIATE_PREFIX__ #
48#endif
49
50/* ANSI concatenation macros.  */
51
52#define CONCAT1(a, b) CONCAT2(a, b)
53#define CONCAT2(a, b) a ## b
54
55/* Use the right prefix for global labels.  */
56
57#define SYM(x) CONCAT1 (__USER_LABEL_PREFIX__, x)
58
59/* Use the right prefix for registers.  */
60
61#define REG(x) CONCAT1 (__REGISTER_PREFIX__, x)
62
63/* Use the right prefix for immediate values.  */
64
65#define IMM(x) CONCAT1 (__IMMEDIATE_PREFIX__, x)
66
67#define d0 REG (d0)
68#define d1 REG (d1)
69#define d2 REG (d2)
70#define d3 REG (d3)
71#define d4 REG (d4)
72#define d5 REG (d5)
73#define d6 REG (d6)
74#define d7 REG (d7)
75#define a0 REG (a0)
76#define a1 REG (a1)
77#define a2 REG (a2)
78#define a3 REG (a3)
79#define a4 REG (a4)
80#define a5 REG (a5)
81#define a6 REG (a6)
82#define fp REG (fp)
83#define sp REG (sp)
84
85	.text
86	.proc
87	.globl	SYM (__divsi3)
88SYM (__divsi3):
89	movel	d2, sp@-
90
91	moveq	IMM (1), d2	/* sign of result stored in d2 (=1 or =-1) */
92	movel	sp@(12), d1	/* d1 = divisor */
93	jpl	L1
94	negl	d1
95#if !(defined(__mcf5200__) || defined(__mcoldfire__))
96	negb	d2		/* change sign because divisor <0  */
97#else
98	negl	d2		/* change sign because divisor <0  */
99#endif
100L1:	movel	sp@(8), d0	/* d0 = dividend */
101	jpl	L2
102	negl	d0
103#if !(defined(__mcf5200__) || defined(__mcoldfire__))
104	negb	d2
105#else
106	negl	d2
107#endif
108
109L2:	movel	d1, sp@-
110	movel	d0, sp@-
111	jbsr	SYM (__udivsi3)	/* divide abs(dividend) by abs(divisor) */
112	addql	IMM (8), sp
113
114	tstb	d2
115	jpl	L3
116	negl	d0
117
118L3:	movel	sp@+, d2
119	rts
120
121