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! Z8000 __mpn_mul_1 -- Multiply a limb vector with a limb and store
! the result in a second limb vector.

! Copyright (C) 1993, 1994, 1995 Free Software Foundation, Inc.

! This file is part of the GNU MP Library.

! The GNU MP Library is free software; you can redistribute it and/or modify
! it under the terms of the GNU Library General Public License as published by
! the Free Software Foundation; either version 2 of the License, or (at your
! option) any later version.

! The GNU MP Library 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 Library General Public
! License for more details.

! You should have received a copy of the GNU Library General Public License
! along with the GNU MP Library; see the file COPYING.LIB.  If not, write to
! the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.


! INPUT PARAMETERS
! res_ptr	r7
! s1_ptr	r6
! size		r5
! s2_limb	r4

	unseg
	.text
	even
	global ___mpn_mul_1
___mpn_mul_1:
	sub	r2,r2		! zero carry limb
	and	r4,r4
	jr	mi,Lneg

Lpos:	pop	r1,@r6
	ld	r9,r1
	mult	rr8,r4
	and	r1,r1		! shift msb of loaded limb into cy
	jr	mi,Lp		! branch if loaded limb's msb is set
	add	r8,r4		! hi_limb += sign_comp2
Lp:	add	r9,r2		! lo_limb += cy_limb
	xor	r2,r2
	adc	r2,r8
	ld	@r7,r9
	inc	r7,#2
	dec	r5
	jr	ne,Lpos
	ret t

Lneg:	pop	r1,@r6
	ld	r9,r1
	mult	rr8,r4
	add	r8,r1		! hi_limb += sign_comp1
	and	r1,r1
	jr	mi,Ln
	add	r8,r4		! hi_limb += sign_comp2
Ln:	add	r9,r2		! lo_limb += cy_limb
	xor	r2,r2
	adc	r2,r8
	ld	@r7,r9
	inc	r7,#2
	dec	r5
	jr	ne,Lneg
	ret t