gcc/gmp/mpn/m68k/mc68020/mul_1.asm

dnl  mc68020 mpn_mul_1 -- mpn by limb multiply

dnl  Copyright 1992, 1994, 1996, 1999, 2000, 2001, 2002 Free Software
dnl  Foundation, Inc.
dnl
dnl  This file is part of the GNU MP Library.
dnl
dnl  The GNU MP Library is free software; you can redistribute it and/or
dnl  modify it under the terms of the GNU Lesser General Public License as
dnl  published by the Free Software Foundation; either version 3 of the
dnl  License, or (at your option) any later version.
dnl
dnl  The GNU MP Library is distributed in the hope that it will be useful,
dnl  but WITHOUT ANY WARRANTY; without even the implied warranty of
dnl  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
dnl  Lesser General Public License for more details.
dnl
dnl  You should have received a copy of the GNU Lesser General Public License
dnl  along with the GNU MP Library.  If not, see http://www.gnu.org/licenses/.

include(`../config.m4')

C         cycles/limb
C 68040:     24

C INPUT PARAMETERS
C res_ptr	(sp + 4)
C s1_ptr	(sp + 8)
C s1_size	(sp + 12)
C s2_limb	(sp + 16)


define(res_ptr, `a0')
define(s1_ptr,  `a1')
define(s1_size, `d2')
define(s2_limb, `d4')


PROLOGUE(mpn_mul_1)

C Save used registers on the stack.
	moveml	d2-d4, M(-,sp)

C	movel	d2, M(-,sp)
C	movel	d3, M(-,sp)
C	movel	d4, M(-,sp)

C Copy the arguments to registers.  Better use movem?
	movel	M(sp,16), res_ptr
	movel	M(sp,20), s1_ptr
	movel	M(sp,24), s1_size
	movel	M(sp,28), s2_limb

	eorw	#1, s1_size
	clrl	d1
	lsrl	#1, s1_size
	bcc	L(L1)
	subql	#1, s1_size
	subl	d0, d0		C (d0,cy) <= (0,0)

L(Loop):
	movel	M(s1_ptr,+), d3
	mulul	s2_limb, d1:d3
	addxl	d0, d3
	movel	d3, M(res_ptr,+)
L(L1):	movel	M(s1_ptr,+), d3
	mulul	s2_limb, d0:d3
	addxl	d1, d3
	movel	d3, M(res_ptr,+)

	dbf	s1_size, L(Loop)
	clrl	d3
	addxl	d3, d0
	subl	#0x10000, s1_size
	bcc	L(Loop)

C Restore used registers from stack frame.
	moveml	M(sp,+), d2-d4

C	movel	M(sp,+),d4
C	movel	M(sp,+),d3
C	movel	M(sp,+),d2

	rts

EPILOGUE(mpn_mul_1)