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Elixir Cross Referencer

dnl  AMD64 mpn_mul_1 for CPUs with mulx.

dnl  Copyright 2012, 2013 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 AMD K8,K9	 -
C AMD K10	 -
C AMD bd1	 -
C AMD bd2	 ?
C AMD bobcat	 -
C AMD jaguar	 ?
C Intel P4	 -
C Intel PNR	 -
C Intel NHM	 -
C Intel SBR	 -
C Intel HWL	 ?
C Intel BWL	 ?
C Intel atom	 -
C VIA nano	 -

define(`rp',      `%rdi')   C rcx
define(`up',      `%rsi')   C rdx
define(`n_param', `%rdx')   C r8
define(`v0_param',`%rcx')   C r9

define(`n',       `%rcx')
define(`v0',      `%rdx')

IFDOS(`	define(`up', ``%rsi'')	') dnl
IFDOS(`	define(`rp', ``%rcx'')	') dnl
IFDOS(`	define(`v0', ``%r9'')	') dnl
IFDOS(`	define(`r9', ``rdi'')	') dnl
IFDOS(`	define(`n',  ``%r8'')	') dnl
IFDOS(`	define(`r8', ``r11'')	') dnl

ASM_START()
	TEXT
	ALIGN(16)
PROLOGUE(mpn_mul_1c)
	jmp	L(ent)
EPILOGUE()
PROLOGUE(mpn_mul_1)
	xor	R32(%r8), R32(%r8)	C carry-in limb
L(ent):	mov	(up), %r9

	push	%rbx
	push	%r12
	push	%r13

	lea	(up,n_param,8), up
	lea	-32(rp,n_param,8), rp
	mov	R32(n_param), R32(%rax)
	xchg	v0_param, v0		C FIXME: is this insn fast?

	neg	n

	and	$3, R8(%rax)
	jz	L(b0)
	cmp	$2, R8(%rax)
	jz	L(b2)
	jg	L(b3)

L(b1):	mov	%r8, %r12
	mulx	%r9, %rbx, %rax
	sub	$-1, n
	jz	L(wd1)
	mulx	(up,n,8), %r9, %r8
	mulx	8(up,n,8), %r11, %r10
	add	%r12, %rbx
	jmp	L(lo1)

L(b3):	mulx	%r9, %r11, %r10
	mulx	8(up,n,8), %r13, %r12
	mulx	16(up,n,8), %rbx, %rax
	sub	$-3, n
	jz	L(wd3)
	add	%r8, %r11
	jmp	L(lo3)

L(b2):	mov	%r8, %r10		C carry-in limb
	mulx	%r9, %r13, %r12
	mulx	8(up,n,8), %rbx, %rax
	sub	$-2, n
	jz	L(wd2)
	mulx	(up,n,8), %r9, %r8
	add	%r10, %r13
	jmp	L(lo2)

L(b0):	mov	%r8, %rax		C carry-in limb
	mulx	%r9, %r9, %r8
	mulx	8(up,n,8), %r11, %r10
	mulx	16(up,n,8), %r13, %r12
	add	%rax, %r9
	jmp	L(lo0)

L(top):	jrcxz	L(end)
	adc	%r8, %r11
	mov	%r9, (rp,n,8)
L(lo3):	mulx	(up,n,8), %r9, %r8
	adc	%r10, %r13
	mov	%r11, 8(rp,n,8)
L(lo2):	mulx	8(up,n,8), %r11, %r10
	adc	%r12, %rbx
	mov	%r13, 16(rp,n,8)
L(lo1):	mulx	16(up,n,8), %r13, %r12
	adc	%rax, %r9
	mov	%rbx, 24(rp,n,8)
L(lo0):	mulx	24(up,n,8), %rbx, %rax
	lea	4(n), n
	jmp	L(top)

L(end):	mov	%r9, (rp)
L(wd3):	adc	%r8, %r11
	mov	%r11, 8(rp)
L(wd2):	adc	%r10, %r13
	mov	%r13, 16(rp)
L(wd1):	adc	%r12, %rbx
	adc	n, %rax
	mov	%rbx, 24(rp)

	pop	%r13
	pop	%r12
	pop	%rbx
	ret
EPILOGUE()
ASM_END()