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dnl  AMD64 mpn_copyi optimised for CPUs with fast SSE copying and SSSE3.

dnl  Copyright 2012, 2013, 2015 Free Software Foundation, Inc.

dnl  Contributed to the GNU project by Torbjörn Granlund.

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     cycles/limb     cycles/limb      good
C              aligned	      unaligned	      best seen	     for cpu?
C AMD K8,K9	 2.0		 illop		1.0/1.0		N
C AMD K10	 0.85		 illop				Y/N
C AMD bull	 0.70		 0.66				Y
C AMD pile	 0.68		 0.66				Y
C AMD steam	 ?		 ?
C AMD excavator	 ?		 ?
C AMD bobcat	 1.97		 8.16		1.5/1.5		N
C AMD jaguar	 0.77		 0.93		0.65/opt	N/Y
C Intel P4	 2.26		 illop				Y/N
C Intel core	 0.52		 0.64		opt/opt		Y
C Intel NHM	 0.52		 0.71		opt/opt		Y
C Intel SBR	 0.51		 0.54		opt/0.51	Y
C Intel IBR	 0.50		 0.54		opt/opt		Y
C Intel HWL	 0.50		 0.51		opt/opt		Y
C Intel BWL	 0.55		 0.55		opt/opt		Y
C Intel atom	 1.16		 1.61		opt/opt		Y
C Intel SLM	 1.02		 1.07		opt/opt		Y
C VIA nano	 1.09		 1.08		opt/opt		Y

C We use only 16-byte operations, except for unaligned top-most and bottom-most
C limbs.  We use the SSSE3 palignr instruction when rp - up = 8 (mod 16).  That
C instruction is better adapted to mpn_copyd's needs, we need to contort the
C code to use it here.
C
C For operands of < COPYI_SSE_THRESHOLD limbs, we use a plain 64-bit loop,
C taken from the x86_64 default code.

C INPUT PARAMETERS
define(`rp', `%rdi')
define(`up', `%rsi')
define(`n',  `%rdx')

C There are three instructions for loading an aligned 128-bit quantity.  We use
C movaps, since it has the shortest coding.
dnl define(`movdqa', ``movaps'')

ifdef(`COPYI_SSE_THRESHOLD',`',`define(`COPYI_SSE_THRESHOLD', 7)')

ASM_START()
	TEXT
	ALIGN(64)
PROLOGUE(mpn_copyi)
	FUNC_ENTRY(3)

	cmp	$COPYI_SSE_THRESHOLD, n
	jbe	L(bc)

	test	$8, R8(rp)		C is rp 16-byte aligned?
	jz	L(rp_aligned)		C jump if rp aligned

	movsq				C copy one limb
	dec	n

L(rp_aligned):
	test	$8, R8(up)
	jnz	L(uent)

ifelse(eval(COPYI_SSE_THRESHOLD >= 8),1,
`	sub	$8, n',
`	jmp	L(am)')

	ALIGN(16)
L(atop):movdqa	0(up), %xmm0
	movdqa	16(up), %xmm1
	movdqa	32(up), %xmm2
	movdqa	48(up), %xmm3
	lea	64(up), up
	movdqa	%xmm0, (rp)
	movdqa	%xmm1, 16(rp)
	movdqa	%xmm2, 32(rp)
	movdqa	%xmm3, 48(rp)
	lea	64(rp), rp
L(am):	sub	$8, n
	jnc	L(atop)

	test	$4, R8(n)
	jz	1f
	movdqa	(up), %xmm0
	movdqa	16(up), %xmm1
	lea	32(up), up
	movdqa	%xmm0, (rp)
	movdqa	%xmm1, 16(rp)
	lea	32(rp), rp

1:	test	$2, R8(n)
	jz	1f
	movdqa	(up), %xmm0
	lea	16(up), up
	movdqa	%xmm0, (rp)
	lea	16(rp), rp

1:	test	$1, R8(n)
	jz	1f
	mov	(up), %r8
	mov	%r8, (rp)

1:	FUNC_EXIT()
	ret

L(uent):
C Code handling up - rp = 8 (mod 16)

	cmp	$16, n
	jc	L(ued0)

IFDOS(`	add	$-56, %rsp	')
IFDOS(`	movdqa	%xmm6, (%rsp)	')
IFDOS(`	movdqa	%xmm7, 16(%rsp)	')
IFDOS(`	movdqa	%xmm8, 32(%rsp)	')

	movaps	120(up), %xmm7
	movaps	104(up), %xmm6
	movaps	88(up), %xmm5
	movaps	72(up), %xmm4
	movaps	56(up), %xmm3
	movaps	40(up), %xmm2
	lea	128(up), up
	sub	$32, n
	jc	L(ued1)

	ALIGN(16)
L(utop):movaps	-104(up), %xmm1
	sub	$16, n
	movaps	-120(up), %xmm0
	palignr($8, %xmm6, %xmm7)
	movaps	-136(up), %xmm8
	movdqa	%xmm7, 112(rp)
	palignr($8, %xmm5, %xmm6)
	movaps	120(up), %xmm7
	movdqa	%xmm6, 96(rp)
	palignr($8, %xmm4, %xmm5)
	movaps	104(up), %xmm6
	movdqa	%xmm5, 80(rp)
	palignr($8, %xmm3, %xmm4)
	movaps	88(up), %xmm5
	movdqa	%xmm4, 64(rp)
	palignr($8, %xmm2, %xmm3)
	movaps	72(up), %xmm4
	movdqa	%xmm3, 48(rp)
	palignr($8, %xmm1, %xmm2)
	movaps	56(up), %xmm3
	movdqa	%xmm2, 32(rp)
	palignr($8, %xmm0, %xmm1)
	movaps	40(up), %xmm2
	movdqa	%xmm1, 16(rp)
	palignr($8, %xmm8, %xmm0)
	lea	128(up), up
	movdqa	%xmm0, (rp)
	lea	128(rp), rp
	jnc	L(utop)

L(ued1):movaps	-104(up), %xmm1
	movaps	-120(up), %xmm0
	movaps	-136(up), %xmm8
	palignr($8, %xmm6, %xmm7)
	movdqa	%xmm7, 112(rp)
	palignr($8, %xmm5, %xmm6)
	movdqa	%xmm6, 96(rp)
	palignr($8, %xmm4, %xmm5)
	movdqa	%xmm5, 80(rp)
	palignr($8, %xmm3, %xmm4)
	movdqa	%xmm4, 64(rp)
	palignr($8, %xmm2, %xmm3)
	movdqa	%xmm3, 48(rp)
	palignr($8, %xmm1, %xmm2)
	movdqa	%xmm2, 32(rp)
	palignr($8, %xmm0, %xmm1)
	movdqa	%xmm1, 16(rp)
	palignr($8, %xmm8, %xmm0)
	movdqa	%xmm0, (rp)
	lea	128(rp), rp

IFDOS(`	movdqa	(%rsp), %xmm6	')
IFDOS(`	movdqa	16(%rsp), %xmm7	')
IFDOS(`	movdqa	32(%rsp), %xmm8	')
IFDOS(`	add	$56, %rsp	')

L(ued0):test	$8, R8(n)
	jz	1f
	movaps	56(up), %xmm3
	movaps	40(up), %xmm2
	movaps	24(up), %xmm1
	movaps	8(up), %xmm0
	movaps	-8(up), %xmm4
	palignr($8, %xmm2, %xmm3)
	movdqa	%xmm3, 48(rp)
	palignr($8, %xmm1, %xmm2)
	movdqa	%xmm2, 32(rp)
	palignr($8, %xmm0, %xmm1)
	movdqa	%xmm1, 16(rp)
	palignr($8, %xmm4, %xmm0)
	lea	64(up), up
	movdqa	%xmm0, (rp)
	lea	64(rp), rp

1:	test	$4, R8(n)
	jz	1f
	movaps	24(up), %xmm1
	movaps	8(up), %xmm0
	palignr($8, %xmm0, %xmm1)
	movaps	-8(up), %xmm3
	movdqa	%xmm1, 16(rp)
	palignr($8, %xmm3, %xmm0)
	lea	32(up), up
	movdqa	%xmm0, (rp)
	lea	32(rp), rp

1:	test	$2, R8(n)
	jz	1f
	movdqa	8(up), %xmm0
	movdqa	-8(up), %xmm3
	palignr($8, %xmm3, %xmm0)
	lea	16(up), up
	movdqa	%xmm0, (rp)
	lea	16(rp), rp

1:	test	$1, R8(n)
	jz	1f
	mov	(up), %r8
	mov	%r8, (rp)

1:	FUNC_EXIT()
	ret

C Basecase code.  Needed for good small operands speed, not for
C correctness as the above code is currently written.

L(bc):	lea	-8(rp), rp
	sub	$4, R32(n)
	jc	L(end)

	ALIGN(16)
L(top):	mov	(up), %r8
	mov	8(up), %r9
	lea	32(rp), rp
	mov	16(up), %r10
	mov	24(up), %r11
	lea	32(up), up
	mov	%r8, -24(rp)
	mov	%r9, -16(rp)
ifelse(eval(COPYI_SSE_THRESHOLD >= 8),1,
`	sub	$4, R32(n)')
	mov	%r10, -8(rp)
	mov	%r11, (rp)
ifelse(eval(COPYI_SSE_THRESHOLD >= 8),1,
`	jnc	L(top)')

L(end):	test	$1, R8(n)
	jz	1f
	mov	(up), %r8
	mov	%r8, 8(rp)
	lea	8(rp), rp
	lea	8(up), up
1:	test	$2, R8(n)
	jz	1f
	mov	(up), %r8
	mov	8(up), %r9
	mov	%r8, 8(rp)
	mov	%r9, 16(rp)
1:	FUNC_EXIT()
	ret
EPILOGUE()