xref: /arch/m68k/lib/divsi3.S

/* libgcc1 routines for 68000 w/o floating-point hardware.
   Copyright (C) 1994, 1996, 1997, 1998 Free Software Foundation, Inc.

This file is part of GNU CC.

GNU CC 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, or (at your option) any
later version.

In addition to the permissions in the GNU General Public License, the
Free Software Foundation gives you unlimited permission to link the
compiled version of this file with other programs, and to distribute
those programs without any restriction coming from the use of this
file.  (The General Public License restrictions do apply in other
respects; for example, they cover modification of the file, and
distribution when not linked into another program.)

This file 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 this program; see the file COPYING.  If not, write to
the Free Software Foundation, 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA.  */

/* As a special exception, if you link this library with files
   compiled with GCC to produce an executable, this does not cause
   the resulting executable to be covered by the GNU General Public License.
   This exception does not however invalidate any other reasons why
   the executable file might be covered by the GNU General Public License.  */

/* Use this one for any 680x0; assumes no floating point hardware.
   The trailing " '" appearing on some lines is for ANSI preprocessors.  Yuk.
   Some of this code comes from MINIX, via the folks at ericsson.
   D. V. Henkel-Wallace (gumby@cygnus.com) Fete Bastille, 1992
*/

/* These are predefined by new versions of GNU cpp.  */

#ifndef __USER_LABEL_PREFIX__
#define __USER_LABEL_PREFIX__ _
#endif

#ifndef __REGISTER_PREFIX__
#define __REGISTER_PREFIX__
#endif

#ifndef __IMMEDIATE_PREFIX__
#define __IMMEDIATE_PREFIX__ #
#endif

/* ANSI concatenation macros.  */

#define CONCAT1(a, b) CONCAT2(a, b)
#define CONCAT2(a, b) a ## b

/* Use the right prefix for global labels.  */

#define SYM(x) CONCAT1 (__USER_LABEL_PREFIX__, x)

/* Use the right prefix for registers.  */

#define REG(x) CONCAT1 (__REGISTER_PREFIX__, x)

/* Use the right prefix for immediate values.  */

#define IMM(x) CONCAT1 (__IMMEDIATE_PREFIX__, x)

#define d0 REG (d0)
#define d1 REG (d1)
#define d2 REG (d2)
#define d3 REG (d3)
#define d4 REG (d4)
#define d5 REG (d5)
#define d6 REG (d6)
#define d7 REG (d7)
#define a0 REG (a0)
#define a1 REG (a1)
#define a2 REG (a2)
#define a3 REG (a3)
#define a4 REG (a4)
#define a5 REG (a5)
#define a6 REG (a6)
#define fp REG (fp)
#define sp REG (sp)

	.text
	.proc
	.globl	SYM (__divsi3)
SYM (__divsi3):
	movel	d2, sp@-

	moveq	IMM (1), d2	/* sign of result stored in d2 (=1 or =-1) */
	movel	sp@(12), d1	/* d1 = divisor */
	jpl	L1
	negl	d1
#if !(defined(__mcf5200__) || defined(__mcoldfire__))
	negb	d2		/* change sign because divisor <0  */
#else
	negl	d2		/* change sign because divisor <0  */
#endif
L1:	movel	sp@(8), d0	/* d0 = dividend */
	jpl	L2
	negl	d0
#if !(defined(__mcf5200__) || defined(__mcoldfire__))
	negb	d2
#else
	negl	d2
#endif

L2:	movel	d1, sp@-
	movel	d0, sp@-
	jbsr	SYM (__udivsi3)	/* divide abs(dividend) by abs(divisor) */
	addql	IMM (8), sp

	tstb	d2
	jpl	L3
	negl	d0

L3:	movel	sp@+, d2
	rts