dnl  mc68020 mpn_add_n, mpn_sub_n -- add or subtract limb vectors

dnl  Copyright 1992, 1994, 1996, 1999-2003, 2005 Free Software Foundation, Inc.

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 modify

dnl  it under the terms of either:

dnl

dnl    * the GNU Lesser General Public License as published by the Free

dnl      Software Foundation; either version 3 of the License, or (at your

dnl      option) any later version.

dnl

dnl  or

dnl

dnl    * the GNU General Public License as published by the Free Software

dnl      Foundation; either version 2 of the License, or (at your option) any

dnl      later version.

dnl

dnl  or both in parallel, as here.

dnl

dnl  The GNU MP Library is distributed in the hope that it will be useful, but

dnl  WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY

dnl  or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

dnl  for more details.

dnl

dnl  You should have received copies of the GNU General Public License and the

dnl  GNU Lesser General Public License along with the GNU MP Library.  If not,

dnl  see https://www.gnu.org/licenses/.

include(`../config.m4')

C         cycles/limb

C 68040:      6

ifdef(`OPERATION_add_n',`

  define(M4_inst,       addxl)

  define(M4_function_n, mpn_add_n)

',`ifdef(`OPERATION_sub_n',`

  define(M4_inst,       subxl)

  define(M4_function_n, mpn_sub_n)

',

`m4_error(`Need OPERATION_add_n or OPERATION_sub_n

')')')

MULFUNC_PROLOGUE(mpn_add_n mpn_sub_n)

C INPUT PARAMETERS

C res_ptr	(sp + 4)

C s1_ptr	(sp + 8)

C s2_ptr	(sp + 12)

C size		(sp + 16)

PROLOGUE(M4_function_n)

C Save used registers on the stack.

	movel	d2, M(-,sp)

	movel	a2, M(-,sp)

C Copy the arguments to registers.  Better use movem?

	movel	M(sp,12), a2

	movel	M(sp,16), a0

	movel	M(sp,20), a1

	movel	M(sp,24), d2

	eorw	#1, d2

	lsrl	#1, d2

	bcc	L(L1)

	subql	#1, d2	C clears cy as side effect

L(Loop):

	movel	M(a0,+), d0

	movel	M(a1,+), d1

	M4_inst	d1, d0

	movel	d0, M(a2,+)

L(L1):	movel	M(a0,+), d0

	movel	M(a1,+), d1

	M4_inst	d1, d0

	movel	d0, M(a2,+)

	dbf	d2, L(Loop)		C loop until 16 lsb of %4 == -1

	subxl	d0, d0			C d0 <= -cy; save cy as 0 or -1 in d0

	subl	#0x10000, d2

	bcs	L(L2)

	addl	d0, d0			C restore cy

	bra	L(Loop)

L(L2):

	negl	d0

C Restore used registers from stack frame.

	movel	M(sp,+), a2

	movel	M(sp,+), d2

	rts

EPILOGUE(M4_function_n)