dnl  AMD64 mpn_mulmid_basecase

dnl  Contributed by David Harvey.

dnl  Copyright 2011, 2012 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 K8,K9:	 2.375  (2.5 when un - vn is "small")

C K10:		 ?

C P4:		 ?

C P6-15:	 ?

C INPUT PARAMETERS

define(`rp',      `%rdi')

define(`up',      `%rsi')

define(`un_param',`%rdx')

define(`vp_param',`%rcx')

define(`vn',      `%r8')

define(`v0', `%r12')

define(`v1', `%r9')

define(`w0', `%rbx')

define(`w1', `%rcx')

define(`w2', `%rbp')

define(`w3', `%r10')

define(`n',  `%r11')

define(`outer_addr', `%r14')

define(`un',  `%r13')

define(`vp',  `%r15')

define(`vp_inner', `%r10')

ABI_SUPPORT(DOS64)

ABI_SUPPORT(STD64)

ASM_START()

	TEXT

	ALIGN(16)

PROLOGUE(mpn_mulmid_basecase)

	FUNC_ENTRY(4)

IFDOS(`	mov	56(%rsp), %r8d	')

	push	%rbx

	push	%rbp

	push	%r12

	push	%r13

	push	%r14

	push	%r15

	mov	vp_param, vp

	C use un for row length (= un_param - vn + 1)

	lea	1(un_param), un

	sub	vn, un

	lea	(rp,un,8), rp

	cmp	$4, un		C TODO: needs tuning

	jc	L(diagonal)

	lea	(up,un_param,8), up

	test	$1, vn

	jz	L(mul_2)

C ===========================================================

C     mul_1 for vp[0] if vn is odd

L(mul_1):

	mov	R32(un), R32(w0)

	neg	un

	mov	(up,un,8), %rax

	mov	(vp), v0

	mul	v0

	and	$-4, un		C round down to multiple of 4

	mov	un, n

	and	$3, R32(w0)

	jz	L(mul_1_prologue_0)

	cmp	$2, R32(w0)

	jc	L(mul_1_prologue_1)

	jz	L(mul_1_prologue_2)

L(mul_1_prologue_3):

	mov	%rax, w3

	mov	%rdx, w0

	lea	L(addmul_prologue_3)(%rip), outer_addr

	jmp	L(mul_1_entry_3)

	ALIGN(16)

L(mul_1_prologue_0):

	mov	%rax, w2

	mov	%rdx, w3		C note already w0 == 0

	lea	L(addmul_prologue_0)(%rip), outer_addr

	jmp	L(mul_1_entry_0)

	ALIGN(16)

L(mul_1_prologue_1):

	add	$4, n

	mov	%rax, w1

	mov	%rdx, w2

	mov	$0, R32(w3)

	mov	(up,n,8), %rax

	lea	L(addmul_prologue_1)(%rip), outer_addr

	jmp	L(mul_1_entry_1)

	ALIGN(16)

L(mul_1_prologue_2):

	mov	%rax, w0

	mov	%rdx, w1

	mov	24(up,n,8), %rax

	mov	$0, R32(w2)

	mov	$0, R32(w3)

	lea	L(addmul_prologue_2)(%rip), outer_addr

	jmp	L(mul_1_entry_2)

	C this loop is 10 c/loop = 2.5 c/l on K8

	ALIGN(16)

L(mul_1_top):

	mov	w0, -16(rp,n,8)

	add	%rax, w1

	mov	(up,n,8), %rax

	adc	%rdx, w2

L(mul_1_entry_1):

	mov	$0, R32(w0)

	mul	v0

	mov	w1, -8(rp,n,8)

	add	%rax, w2

	adc	%rdx, w3

L(mul_1_entry_0):

	mov	8(up,n,8), %rax

	mul	v0

	mov	w2, (rp,n,8)

	add	%rax, w3

	adc	%rdx, w0

L(mul_1_entry_3):

	mov	16(up,n,8), %rax

	mul	v0

	mov	w3, 8(rp,n,8)

	mov	$0, R32(w2)		C zero

	mov	w2, w3			C zero

	add	%rax, w0

	mov	24(up,n,8), %rax

	mov	w2, w1			C zero

	adc	%rdx, w1

L(mul_1_entry_2):

	mul	v0

	add	$4, n

	js	L(mul_1_top)

	mov	w0, -16(rp)

	add	%rax, w1

	mov	w1, -8(rp)

	mov	w2, 8(rp)		C zero last limb of output

	adc	%rdx, w2

	mov	w2, (rp)

	dec	vn

	jz	L(ret)

	lea	-8(up), up

	lea	8(vp), vp

	mov	un, n

	mov	(vp), v0

	mov	8(vp), v1

	jmp	*outer_addr

C ===========================================================

C     mul_2 for vp[0], vp[1] if vn is even

	ALIGN(16)

L(mul_2):

	mov	R32(un), R32(w0)

	neg	un

	mov	-8(up,un,8), %rax

	mov	(vp), v0

	mov	8(vp), v1

	mul	v1

	and	$-4, un		C round down to multiple of 4

	mov	un, n

	and	$3, R32(w0)

	jz	L(mul_2_prologue_0)

	cmp	$2, R32(w0)

	jc	L(mul_2_prologue_1)

	jz	L(mul_2_prologue_2)

L(mul_2_prologue_3):

	mov	%rax, w1

	mov	%rdx, w2

	lea	L(addmul_prologue_3)(%rip), outer_addr

	jmp	L(mul_2_entry_3)

	ALIGN(16)

L(mul_2_prologue_0):

	mov	%rax, w0

	mov	%rdx, w1

	lea	L(addmul_prologue_0)(%rip), outer_addr

	jmp	L(mul_2_entry_0)

	ALIGN(16)

L(mul_2_prologue_1):

	mov	%rax, w3

	mov	%rdx, w0

	mov	$0, R32(w1)

	lea	L(addmul_prologue_1)(%rip), outer_addr

	jmp	L(mul_2_entry_1)

	ALIGN(16)

L(mul_2_prologue_2):

	mov	%rax, w2

	mov	%rdx, w3

	mov	$0, R32(w0)

	mov	16(up,n,8), %rax

	lea	L(addmul_prologue_2)(%rip), outer_addr

	jmp	L(mul_2_entry_2)

	C this loop is 18 c/loop = 2.25 c/l on K8

	ALIGN(16)

L(mul_2_top):

	mov     -8(up,n,8), %rax

	mul     v1

	add     %rax, w0

	adc     %rdx, w1

L(mul_2_entry_0):

	mov     $0, R32(w2)

	mov     (up,n,8), %rax

	mul     v0

	add     %rax, w0

	mov     (up,n,8), %rax

	adc     %rdx, w1

	adc     $0, R32(w2)

	mul     v1

	add     %rax, w1

	mov     w0, (rp,n,8)

	adc     %rdx, w2

L(mul_2_entry_3):

	mov     8(up,n,8), %rax

	mul     v0

	mov     $0, R32(w3)

	add     %rax, w1

	adc     %rdx, w2

	mov     $0, R32(w0)

	adc     $0, R32(w3)

	mov     8(up,n,8), %rax

	mov     w1, 8(rp,n,8)

	mul     v1

	add     %rax, w2

	mov     16(up,n,8), %rax

	adc     %rdx, w3

L(mul_2_entry_2):

	mov     $0, R32(w1)

	mul     v0

	add     %rax, w2

	mov     16(up,n,8), %rax

	adc     %rdx, w3

	adc     $0, R32(w0)

	mul     v1

	add     %rax, w3

	mov     w2, 16(rp,n,8)

	adc     %rdx, w0

L(mul_2_entry_1):

	mov     24(up,n,8), %rax

	mul     v0

	add     %rax, w3

	adc     %rdx, w0

	adc     $0, R32(w1)

	add     $4, n

	mov     w3, -8(rp,n,8)

	jnz     L(mul_2_top)

	mov	w0, (rp)

	mov	w1, 8(rp)

	sub	$2, vn

	jz	L(ret)

	lea	16(vp), vp

	lea	-16(up), up

	mov	un, n

	mov	(vp), v0

	mov	8(vp), v1

	jmp	*outer_addr

C ===========================================================

C     addmul_2 for remaining vp's

	ALIGN(16)

L(addmul_prologue_0):

	mov	-8(up,n,8), %rax

	mul	v1

	mov	%rax, w1

	mov	%rdx, w2

	mov	$0, R32(w3)

	jmp	L(addmul_entry_0)

	ALIGN(16)

L(addmul_prologue_1):

	mov	16(up,n,8), %rax

	mul	v1

	mov	%rax, w0

	mov	%rdx, w1

	mov	$0, R32(w2)

	mov	24(up,n,8), %rax

	jmp	L(addmul_entry_1)

	ALIGN(16)

L(addmul_prologue_2):

	mov	8(up,n,8), %rax

	mul	v1

	mov	%rax, w3

	mov	%rdx, w0

	mov	$0, R32(w1)

	jmp	L(addmul_entry_2)

	ALIGN(16)

L(addmul_prologue_3):

	mov	(up,n,8), %rax

	mul	v1

	mov	%rax, w2

	mov	%rdx, w3

	mov	$0, R32(w0)

	mov	$0, R32(w1)

	jmp	L(addmul_entry_3)

	C this loop is 19 c/loop = 2.375 c/l on K8

	ALIGN(16)

L(addmul_top):

	mov	$0, R32(w3)

	add	%rax, w0

	mov	-8(up,n,8), %rax

	adc	%rdx, w1

	adc	$0, R32(w2)

	mul	v1

	add	w0, -8(rp,n,8)

	adc	%rax, w1

	adc	%rdx, w2

L(addmul_entry_0):

	mov	(up,n,8), %rax

	mul	v0

	add	%rax, w1

	mov	(up,n,8), %rax

	adc	%rdx, w2

	adc	$0, R32(w3)

	mul	v1

	add	w1, (rp,n,8)

	mov	$0, R32(w1)

	adc	%rax, w2

	mov	$0, R32(w0)

	adc	%rdx, w3

L(addmul_entry_3):

	mov	8(up,n,8), %rax

	mul	v0

	add	%rax, w2

	mov	8(up,n,8), %rax

	adc	%rdx, w3

	adc	$0, R32(w0)

	mul	v1

	add	w2, 8(rp,n,8)

	adc	%rax, w3

	adc	%rdx, w0

L(addmul_entry_2):

	mov	16(up,n,8), %rax

	mul	v0

	add	%rax, w3

	mov	16(up,n,8), %rax

	adc	%rdx, w0

	adc	$0, R32(w1)

	mul	v1

	add	w3, 16(rp,n,8)

	nop			C don't ask...

	adc	%rax, w0

	mov	$0, R32(w2)

	mov	24(up,n,8), %rax

	adc	%rdx, w1

L(addmul_entry_1):

	mul	v0

	add	$4, n

	jnz	L(addmul_top)

	add	%rax, w0

	adc	%rdx, w1

	adc	$0, R32(w2)

	add	w0, -8(rp)

	adc	w1, (rp)

	adc	w2, 8(rp)

	sub	$2, vn

	jz	L(ret)

	lea	16(vp), vp

	lea	-16(up), up

	mov	un, n

	mov	(vp), v0

	mov	8(vp), v1

	jmp	*outer_addr

C ===========================================================

C     accumulate along diagonals if un - vn is small

	ALIGN(16)

L(diagonal):

	xor	R32(w0), R32(w0)

	xor	R32(w1), R32(w1)

	xor	R32(w2), R32(w2)

	neg	un

	mov	R32(vn), %eax

	and	$3, %eax

	jz	L(diag_prologue_0)

	cmp	$2, %eax

	jc	L(diag_prologue_1)

	jz	L(diag_prologue_2)

L(diag_prologue_3):

	lea	-8(vp), vp

	mov	vp, vp_inner

	add	$1, vn

	mov	vn, n

	lea	L(diag_entry_3)(%rip), outer_addr

	jmp	L(diag_entry_3)

L(diag_prologue_0):

	mov	vp, vp_inner

	mov	vn, n

	lea	0(%rip), outer_addr

	mov     -8(up,n,8), %rax

	jmp	L(diag_entry_0)

L(diag_prologue_1):

	lea	8(vp), vp

	mov	vp, vp_inner

	add	$3, vn

	mov	vn, n

	lea	0(%rip), outer_addr

	mov     -8(vp_inner), %rax

	jmp	L(diag_entry_1)

L(diag_prologue_2):

	lea	-16(vp), vp

	mov	vp, vp_inner

	add	$2, vn

	mov	vn, n

	lea	0(%rip), outer_addr

	mov	16(vp_inner), %rax

	jmp	L(diag_entry_2)

	C this loop is 10 c/loop = 2.5 c/l on K8

	ALIGN(16)

L(diag_top):

	add     %rax, w0

	adc     %rdx, w1

	mov     -8(up,n,8), %rax

	adc     $0, w2

L(diag_entry_0):

	mulq    (vp_inner)

	add     %rax, w0

	adc     %rdx, w1

	adc     $0, w2

L(diag_entry_3):

	mov     -16(up,n,8), %rax

	mulq    8(vp_inner)

	add     %rax, w0

	mov     16(vp_inner), %rax

	adc     %rdx, w1

	adc     $0, w2

L(diag_entry_2):

	mulq    -24(up,n,8)

	add     %rax, w0

	mov     24(vp_inner), %rax

	adc     %rdx, w1

	lea     32(vp_inner), vp_inner

	adc     $0, w2

L(diag_entry_1):

	mulq    -32(up,n,8)

	sub     $4, n

	jnz	L(diag_top)

	add	%rax, w0

	adc	%rdx, w1

	adc	$0, w2

	mov	w0, (rp,un,8)

	inc	un

	jz	L(diag_end)

	mov	vn, n

	mov	vp, vp_inner

	lea	8(up), up

	mov	w1, w0

	mov	w2, w1

	xor	R32(w2), R32(w2)

	jmp	*outer_addr

L(diag_end):

	mov	w1, (rp)

	mov	w2, 8(rp)

L(ret):	pop	%r15

	pop	%r14

	pop	%r13

	pop	%r12

	pop	%rbp

	pop	%rbx

	FUNC_EXIT()

	ret

EPILOGUE()