dnl  x86_64 mpn_bdiv_dbm1.

dnl  Copyright 2008, 2011, 2012 Free Software Foundation, Inc.

dnl  This file is part of the GNU MP Library.

dnl  The GNU MP Library is free software; you can redistribute it and/or modify
dnl  it under the terms of the GNU Lesser General Public License as published
dnl  by the Free Software Foundation; either version 3 of the License, or (at
dnl  your option) any later version.

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 Lesser General Public
dnl  License for more details.

dnl  You should have received a copy of the GNU Lesser General Public License
dnl  along with the GNU MP Library.  If not, see http://www.gnu.org/licenses/.

include(`../config.m4')

C	     cycles/limb
C AMD K8,K9	 2.25
C AMD K10	 2.25
C Intel P4	12.5
C Intel core2	 4
C Intel NHM	 3.75
C Intel SBR	 3.6
C Intel atom	20
C VIA nano	 4

C TODO
C  * Optimise feed-in code.

C INPUT PARAMETERS
define(`qp',	  `%rdi')
define(`up',	  `%rsi')
define(`n_param', `%rdx')
define(`bd',	  `%rcx')
define(`cy',	  `%r8')

define(`n',       `%r9')

ABI_SUPPORT(DOS64)
ABI_SUPPORT(STD64)

ASM_START()
	TEXT
	ALIGN(16)
PROLOGUE(mpn_bdiv_dbm1c)
	FUNC_ENTRY(4)
IFDOS(`	mov	56(%rsp), %r8	')
	mov	(up), %rax
	mov	n_param, n
	mov	R32(n_param), R32(%r11)
	mul	bd
	lea	(up,n,8), up
	lea	(qp,n,8), qp
	neg	n
	and	$3, R32(%r11)
	jz	L(lo0)
	lea	-4(n,%r11), n
	cmp	$2, R32(%r11)
	jc	L(lo1)
	jz	L(lo2)
	jmp	L(lo3)

	ALIGN(16)
L(top):	mov	(up,n,8), %rax
	mul	bd
L(lo0):	sub	%rax, %r8
	mov	%r8, (qp,n,8)
	sbb	%rdx, %r8
	mov	8(up,n,8), %rax
	mul	bd
L(lo3):	sub	%rax, %r8
	mov	%r8, 8(qp,n,8)
	sbb	%rdx, %r8
	mov	16(up,n,8), %rax
	mul	bd
L(lo2):	sub	%rax, %r8
	mov	%r8, 16(qp,n,8)
	sbb	%rdx, %r8
	mov	24(up,n,8), %rax
	mul	bd
L(lo1):	sub	%rax, %r8
	mov	%r8, 24(qp,n,8)
	sbb	%rdx, %r8
	add	$4, n
	jnz	L(top)

	mov	%r8, %rax
	FUNC_EXIT()
	ret
EPILOGUE()