/* SPARC v9 __mpn_sub_n -- Subtract two limb vectors of the same length > 0

   and store difference in a third limb vector.

   Copyright (C) 1995-2018 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 Lesser General Public License as published by

   the Free Software Foundation; either version 2.1 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 Lesser General Public

   License for more details.

   You should have received a copy of the GNU Lesser General Public License

   along with the GNU MP Library; see the file COPYING.LIB.  If not,

   see <http://www.gnu.org/licenses/>.  */

#include <sysdep.h>

/* INPUT PARAMETERS

   res_ptr	%o0

   s1_ptr	%o1

   s2_ptr	%o2

   size		%o3  */

ENTRY(__mpn_sub_n)

	sub %g0,%o3,%g5

	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 %g5,3,%o5			! compute initial address index

1:	ldx [%o2+%o5],%g1		! load s2 limb

	add %g5,1,%g5			! increment loop count

	ldx [%o1+%o5],%o3		! 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 %o3,%g1,%g1		! subtract s1 limb from sum

	stx %g1,[%o0+%o5]		! store result

	add %o5,8,%o5			! increment address index

	brnz,pt %g5,1b

	 movcs %xcc,1,%o4		! if s1 subtract gave carry, record it

	retl

	 mov %o4,%o0

END(__mpn_sub_n)