dnl  SPARC mpn_add_n -- Add two limb vectors of the same length > 0 and store
dnl  sum in a third limb vector.

dnl  Copyright 1995, 1996, 2000 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 INPUT PARAMETERS
define(res_ptr,%o0)
define(s1_ptr,%o1)
define(s2_ptr,%o2)
define(n,%o3)

ASM_START()
PROLOGUE(mpn_add_n)
	xor	s2_ptr,res_ptr,%g1
	andcc	%g1,4,%g0
	bne	L(1)			C branch if alignment differs
	nop
C **  V1a  **
L(0):	andcc	res_ptr,4,%g0		C res_ptr unaligned? Side effect: cy=0
	be	L(v1)			C if no, branch
	nop
C Add least significant limb separately to align res_ptr and s2_ptr
	ld	[s1_ptr],%g4
	add	s1_ptr,4,s1_ptr
	ld	[s2_ptr],%g2
	add	s2_ptr,4,s2_ptr
	add	n,-1,n
	addcc	%g4,%g2,%o4
	st	%o4,[res_ptr]
	add	res_ptr,4,res_ptr
L(v1):	addx	%g0,%g0,%o4		C save cy in register
	cmp	n,2			C if n < 2 ...
	bl	L(end2)			C ... branch to tail code
	subcc	%g0,%o4,%g0		C restore cy

	ld	[s1_ptr+0],%g4
	addcc	n,-10,n
	ld	[s1_ptr+4],%g1
	ldd	[s2_ptr+0],%g2
	blt	L(fin1)
	subcc	%g0,%o4,%g0		C restore cy
C Add blocks of 8 limbs until less than 8 limbs remain
L(loop1):
	addxcc	%g4,%g2,%o4
	ld	[s1_ptr+8],%g4
	addxcc	%g1,%g3,%o5
	ld	[s1_ptr+12],%g1
	ldd	[s2_ptr+8],%g2
	std	%o4,[res_ptr+0]
	addxcc	%g4,%g2,%o4
	ld	[s1_ptr+16],%g4
	addxcc	%g1,%g3,%o5
	ld	[s1_ptr+20],%g1
	ldd	[s2_ptr+16],%g2
	std	%o4,[res_ptr+8]
	addxcc	%g4,%g2,%o4
	ld	[s1_ptr+24],%g4
	addxcc	%g1,%g3,%o5
	ld	[s1_ptr+28],%g1
	ldd	[s2_ptr+24],%g2
	std	%o4,[res_ptr+16]
	addxcc	%g4,%g2,%o4
	ld	[s1_ptr+32],%g4
	addxcc	%g1,%g3,%o5
	ld	[s1_ptr+36],%g1
	ldd	[s2_ptr+32],%g2
	std	%o4,[res_ptr+24]
	addx	%g0,%g0,%o4		C save cy in register
	addcc	n,-8,n
	add	s1_ptr,32,s1_ptr
	add	s2_ptr,32,s2_ptr
	add	res_ptr,32,res_ptr
	bge	L(loop1)
	subcc	%g0,%o4,%g0		C restore cy

L(fin1):
	addcc	n,8-2,n
	blt	L(end1)
	subcc	%g0,%o4,%g0		C restore cy
C Add blocks of 2 limbs until less than 2 limbs remain
L(loope1):
	addxcc	%g4,%g2,%o4
	ld	[s1_ptr+8],%g4
	addxcc	%g1,%g3,%o5
	ld	[s1_ptr+12],%g1
	ldd	[s2_ptr+8],%g2
	std	%o4,[res_ptr+0]
	addx	%g0,%g0,%o4		C save cy in register
	addcc	n,-2,n
	add	s1_ptr,8,s1_ptr
	add	s2_ptr,8,s2_ptr
	add	res_ptr,8,res_ptr
	bge	L(loope1)
	subcc	%g0,%o4,%g0		C restore cy
L(end1):
	addxcc	%g4,%g2,%o4
	addxcc	%g1,%g3,%o5
	std	%o4,[res_ptr+0]
	addx	%g0,%g0,%o4		C save cy in register

	andcc	n,1,%g0
	be	L(ret1)
	subcc	%g0,%o4,%g0		C restore cy
C Add last limb
	ld	[s1_ptr+8],%g4
	ld	[s2_ptr+8],%g2
	addxcc	%g4,%g2,%o4
	st	%o4,[res_ptr+8]

L(ret1):
	retl
	addx	%g0,%g0,%o0	C return carry-out from most sign. limb

L(1):	xor	s1_ptr,res_ptr,%g1
	andcc	%g1,4,%g0
	bne	L(2)
	nop
C **  V1b  **
	mov	s2_ptr,%g1
	mov	s1_ptr,s2_ptr
	b	L(0)
	mov	%g1,s1_ptr

C **  V2  **
C If we come here, the alignment of s1_ptr and res_ptr as well as the
C alignment of s2_ptr and res_ptr differ.  Since there are only two ways
C things can be aligned (that we care about) we now know that the alignment
C of s1_ptr and s2_ptr are the same.

L(2):	cmp	n,1
	be	L(jone)
	nop
	andcc	s1_ptr,4,%g0		C s1_ptr unaligned? Side effect: cy=0
	be	L(v2)			C if no, branch
	nop
C Add least significant limb separately to align s1_ptr and s2_ptr
	ld	[s1_ptr],%g4
	add	s1_ptr,4,s1_ptr
	ld	[s2_ptr],%g2
	add	s2_ptr,4,s2_ptr
	add	n,-1,n
	addcc	%g4,%g2,%o4
	st	%o4,[res_ptr]
	add	res_ptr,4,res_ptr

L(v2):	addx	%g0,%g0,%o4		C save cy in register
	addcc	n,-8,n
	blt	L(fin2)
	subcc	%g0,%o4,%g0		C restore cy
C Add blocks of 8 limbs until less than 8 limbs remain
L(loop2):
	ldd	[s1_ptr+0],%g2
	ldd	[s2_ptr+0],%o4
	addxcc	%g2,%o4,%g2
	st	%g2,[res_ptr+0]
	addxcc	%g3,%o5,%g3
	st	%g3,[res_ptr+4]
	ldd	[s1_ptr+8],%g2
	ldd	[s2_ptr+8],%o4
	addxcc	%g2,%o4,%g2
	st	%g2,[res_ptr+8]
	addxcc	%g3,%o5,%g3
	st	%g3,[res_ptr+12]
	ldd	[s1_ptr+16],%g2
	ldd	[s2_ptr+16],%o4
	addxcc	%g2,%o4,%g2
	st	%g2,[res_ptr+16]
	addxcc	%g3,%o5,%g3
	st	%g3,[res_ptr+20]
	ldd	[s1_ptr+24],%g2
	ldd	[s2_ptr+24],%o4
	addxcc	%g2,%o4,%g2
	st	%g2,[res_ptr+24]
	addxcc	%g3,%o5,%g3
	st	%g3,[res_ptr+28]
	addx	%g0,%g0,%o4		C save cy in register
	addcc	n,-8,n
	add	s1_ptr,32,s1_ptr
	add	s2_ptr,32,s2_ptr
	add	res_ptr,32,res_ptr
	bge	L(loop2)
	subcc	%g0,%o4,%g0		C restore cy

L(fin2):
	addcc	n,8-2,n
	blt	L(end2)
	subcc	%g0,%o4,%g0		C restore cy
L(loope2):
	ldd	[s1_ptr+0],%g2
	ldd	[s2_ptr+0],%o4
	addxcc	%g2,%o4,%g2
	st	%g2,[res_ptr+0]
	addxcc	%g3,%o5,%g3
	st	%g3,[res_ptr+4]
	addx	%g0,%g0,%o4		C save cy in register
	addcc	n,-2,n
	add	s1_ptr,8,s1_ptr
	add	s2_ptr,8,s2_ptr
	add	res_ptr,8,res_ptr
	bge	L(loope2)
	subcc	%g0,%o4,%g0		C restore cy
L(end2):
	andcc	n,1,%g0
	be	L(ret2)
	subcc	%g0,%o4,%g0		C restore cy
C Add last limb
L(jone):
	ld	[s1_ptr],%g4
	ld	[s2_ptr],%g2
	addxcc	%g4,%g2,%o4
	st	%o4,[res_ptr]

L(ret2):
	retl
	addx	%g0,%g0,%o0	C return carry-out from most sign. limb
EPILOGUE(mpn_add_n)