/* SPARC v9 __mpn_sub_n -- Subtract two limb vectors of the same length > 0
   and store difference in a third limb vector.

   Copyright (C) 1995, 1996 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., 59 Temple Place - Suite 330, Boston,
   MA 02111-1307, USA.  */

#include <sysdep.h>

/* INPUT PARAMETERS
   res_ptr	%o0
   s1_ptr	%o1
   s2_ptr	%o2
   size		%o3  */

ENTRY(__mpn_sub_n)

	sub %g0,%o3,%g3
	sllx %o3,3,%g1
	add %o1,%g1,%o1			! make s1_ptr point at end
	add %o2,%g1,%o2			! make s2_ptr point at end
	add %o0,%g1,%o0			! make res_ptr point at end
	mov 0,%o4			! clear carry variable
	sllx %g3,3,%o5			! compute initial address index

1:	ldx [%o2+%o5],%g1		! load s2 limb
	add %g3,1,%g3			! increment loop count
	ldx [%o1+%o5],%g2		! load s1 limb
	addcc %g1,%o4,%g1		! add s2 limb and carry variable
	movcc %xcc,0,%o4		! if carry-out, o4 was 1; clear it
	subcc %g1,%g2,%g1		! subtract s1 limb from sum
	stx %g1,[%o0+%o5]		! store result
	add %o5,8,%o5			! increment address index
	brnz,pt %g3,1b
	 movcs %xcc,1,%o4		! if s1 subtract gave carry, record it

	retl
	 mov %o4,%o0

END(__mpn_sub_n)