Training courses

Kernel and Embedded Linux

Bootlin training courses

Embedded Linux, kernel,
Yocto Project, Buildroot, real-time,
graphics, boot time, debugging...

Bootlin logo

Elixir Cross Referencer

dnl  AMD64 mpn_addmul_1 and mpn_submul_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')

ifdef(`OPERATION_addmul_1',`
      define(`ADDSUB',        `add')
      define(`ADCSBB',        `adc')
      define(`func',  `mpn_addmul_1')
')
ifdef(`OPERATION_submul_1',`
      define(`ADDSUB',        `sub')
      define(`ADCSBB',        `sbb')
      define(`func',  `mpn_submul_1')
')

MULFUNC_PROLOGUE(mpn_addmul_1 mpn_submul_1)

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

ASM_START()
	TEXT
	ALIGN(16)
PROLOGUE(func)
	mov	(up), %r8

	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):	mulx	%r8, %rbx, %rax
	sub	$-1, n
	jz	L(wd1)
	mulx	(up,n,8), %r9, %r8
	mulx	8(up,n,8), %r11, %r10
	test	R32(%rax), R32(%rax)		C clear cy
	jmp	L(lo1)

L(b0):	mulx	%r8, %r9, %r8
	mulx	8(up,n,8), %r11, %r10
	mulx	16(up,n,8), %r13, %r12
	xor	R32(%rax), R32(%rax)
	jmp	L(lo0)

L(b3):	mulx	%r8, %r11, %r10
	mulx	8(up,n,8), %r13, %r12
	mulx	16(up,n,8), %rbx, %rax
	add	%r10, %r13
	adc	%r12, %rbx
	adc	$0, %rax
	sub	$-3, n
	jz	L(wd3)
	test	R32(%rax), R32(%rax)		C clear cy
	jmp	L(lo3)

L(b2):	mulx	%r8, %r13, %r12
	mulx	8(up,n,8), %rbx, %rax
	add	%r12, %rbx
	adc	$0, %rax
	sub	$-2, n
	jz	L(wd2)
	mulx	(up,n,8), %r9, %r8
	test	R32(%rax), R32(%rax)		C clear cy
	jmp	L(lo2)

L(top):	ADDSUB	%r9, (rp,n,8)
L(lo3):	mulx	(up,n,8), %r9, %r8
	ADCSBB	%r11, 8(rp,n,8)
L(lo2):	mulx	8(up,n,8), %r11, %r10
	ADCSBB	%r13, 16(rp,n,8)
L(lo1):	mulx	16(up,n,8), %r13, %r12
	ADCSBB	%rbx, 24(rp,n,8)
	adc	%rax, %r9
L(lo0):	mulx	24(up,n,8), %rbx, %rax
	adc	%r8, %r11
	adc	%r10, %r13
	adc	%r12, %rbx
	adc	$0, %rax		C rax = carry limb
	add	$4, n
	js	L(top)

L(end):	ADDSUB	%r9, (rp)
L(wd3):	ADCSBB	%r11, 8(rp)
L(wd2):	ADCSBB	%r13, 16(rp)
L(wd1):	ADCSBB	%rbx, 24(rp)
	adc	n, %rax
	pop	%r13
	pop	%r12
	pop	%rbx
	ret
EPILOGUE()
ASM_END()