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Elixir Cross Referencer

dnl  ARM64 mpn_cnd_add_n, mpn_cnd_sub_n

dnl  Contributed to the GNU project by Torbjörn Granlund.

dnl  Copyright 2012, 2013, 2017 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 Cortex-A53	3.87-4.37
C Cortex-A57	 1.75
C X-Gene	 2.0

changecom(blah)

define(`cnd',	`x0')
define(`rp',	`x1')
define(`up',	`x2')
define(`vp',	`x3')
define(`n',	`x4')

ifdef(`OPERATION_cnd_add_n', `
  define(`ADDSUBC',	adcs)
  define(`CLRCY',	`cmn	xzr, xzr')
  define(`RETVAL',	`cset	x0, cs')
  define(`func',	mpn_cnd_add_n)')
ifdef(`OPERATION_cnd_sub_n', `
  define(`ADDSUBC',	sbcs)
  define(`CLRCY',	`cmp	xzr, xzr')
  define(`RETVAL',	`cset	x0, cc')
  define(`func',	mpn_cnd_sub_n)')

MULFUNC_PROLOGUE(mpn_cnd_add_n mpn_cnd_sub_n)

ASM_START()
PROLOGUE(func)
	cmp	cnd, #1
	sbc	cnd, cnd, cnd

	CLRCY

	lsr	x18, n, #2
	tbz	n, #0, L(bx0)

L(bx1):	ldr	x13, [vp]
	ldr	x11, [up]
	bic	x7, x13, cnd
	ADDSUBC	x9, x11, x7
	str	x9, [rp]
	tbnz	n, #1, L(b11)

L(b01):	cbz	x18, L(rt)
	ldp	x12, x13, [vp,#8]
	ldp	x10, x11, [up,#8]
	sub	up, up, #8
	sub	vp, vp, #8
	sub	rp, rp, #24
	b	L(mid)

L(b11):	ldp	x12, x13, [vp,#8]!
	ldp	x10, x11, [up,#8]!
	sub	rp, rp, #8
	cbz	x18, L(end)
	b	L(top)

L(bx0):	ldp	x12, x13, [vp]
	ldp	x10, x11, [up]
	tbnz	n, #1, L(b10)

L(b00):	sub	up, up, #16
	sub	vp, vp, #16
	sub	rp, rp, #32
	b	L(mid)

L(b10):	sub	rp, rp, #16
	cbz	x18, L(end)

	ALIGN(16)
L(top):	bic	x6, x12, cnd
	bic	x7, x13, cnd
	ldp	x12, x13, [vp,#16]
	ADDSUBC	x8, x10, x6
	ADDSUBC	x9, x11, x7
	ldp	x10, x11, [up,#16]
	stp	x8, x9, [rp,#16]
L(mid):	bic	x6, x12, cnd
	bic	x7, x13, cnd
	ldp	x12, x13, [vp,#32]!
	ADDSUBC	x8, x10, x6
	ADDSUBC	x9, x11, x7
	ldp	x10, x11, [up,#32]!
	stp	x8, x9, [rp,#32]!
	sub	x18, x18, #1
	cbnz	x18, L(top)

L(end):	bic	x6, x12, cnd
	bic	x7, x13, cnd
	ADDSUBC	x8, x10, x6
	ADDSUBC	x9, x11, x7
	stp	x8, x9, [rp,#16]
L(rt):	RETVAL
	ret
EPILOGUE()