dnl  AMD64 MULX/ADX simulation support.

dnl  Contributed to the GNU project by Torbjörn Granlund.

dnl  Copyright 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')

ASM_START()

C Fake the MULX instruction

C

C Accept the single explicit parameter on the stack, return the two result

C words on the stack.  This calling convention means that we need to move the

C return address up.

C

PROLOGUE(__gmp_mulx)

	lea	-8(%rsp), %rsp

	push	%rax

	push	%rdx

	pushfq				C preserve all flags

	mov	32(%rsp), %rax		C move retaddr...

	mov	%rax, 24(%rsp)		C ...up the stack

	mov	40(%rsp), %rax		C input parameter

	mul	%rdx

	mov	%rax, 32(%rsp)

	mov	%rdx, 40(%rsp)

	popfq				C restore eflags

	pop	%rdx

	pop	%rax

	ret

EPILOGUE()

PROTECT(__gmp_mulx)

C Fake the ADOX instruction

C

C Accept the two parameters on the stack, return the result word on the stack.

C This calling convention means that we need to move the return address down.

C

PROLOGUE(__gmp_adox)

	push	%rcx

	push	%rbx

	push	%rax

	mov	32(%rsp), %rcx		C src2

	mov	24(%rsp), %rax		C move retaddr...

	mov	%rax, 32(%rsp)		C ...down the stack

	pushfq

C copy 0(%rsp):11 to 0(%rsp):0

	mov	(%rsp), %rbx

	shr	%rbx

	bt	$10, %rbx

	adc	%rbx, %rbx

	push	%rbx

C put manipulated flags into eflags, execute a plain adc

	popfq

	adc	%rcx, 48(%rsp)

C copy CF to 0(%rsp):11

	pop	%rbx

	sbb	R32(%rax), R32(%rax)

	and	$0x800, R32(%rax)

	and	$0xfffffffffffff7ff, %rbx

	or	%rax, %rbx

	push	%rbx

C put manipulated flags into eflags

	popfq

	pop	%rax

	pop	%rbx

	pop	%rcx

	lea	8(%rsp), %rsp

	ret

EPILOGUE()

PROTECT(__gmp_adox)

C Fake the ADCX instruction

C

C Accept the two parameters on the stack, return the result word on the stack.

C This calling convention means that we need to move the return address down.

C

PROLOGUE(__gmp_adcx)

	push	%rcx

	push	%rbx

	push	%rax

	mov	32(%rsp), %rcx		C src2

	mov	24(%rsp), %rax		C move retaddr...

	mov	%rax, 32(%rsp)		C ...down the stack

	pushfq

	adc	%rcx, 48(%rsp)

	pop	%rbx

	sbb	R32(%rax), R32(%rax)

	and	$`'0xfffffffffffffffe, %rbx

	sub	%rax, %rbx

	push	%rbx

	popfq

	pop	%rax

	pop	%rbx

	pop	%rcx

	lea	8(%rsp), %rsp

	ret

EPILOGUE()

PROTECT(__gmp_adcx)

CF_PROT