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/* i80386 __mpn_sub_n -- Add two limb vectors of the same length > 0 and store
   sum in a third limb vector.

Copyright (C) 1992, 1994, 1995, 1996, 1999, 2000 Free Software Foundation,
Inc.

This file is part of the GNU MP Library.

The GNU MP Library is free software; you can redistribute it and/or modify
it under the terms of the GNU Library General Public License as published by
the Free Software Foundation; either version 2 of the License, or (at your
option) any later version.

The GNU MP Library is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Library General Public
License for more details.

You should have received a copy of the GNU Library General Public License
along with the GNU MP Library; see the file COPYING.LIB.  If not, write to
the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
MA 02111-1307, USA. */

/*
  INPUT PARAMETERS
  res_ptr	(sp + 4)
  s1_ptr	(sp + 8)
  s2_ptr	(sp + 12)
  size		(sp + 16)
*/

#include "asm-syntax.h"

.text
	ALIGN (3)
	.globl C_SYMBOL_NAME(__mpn_sub_nc)
C_SYMBOL_NAME(__mpn_sub_nc:)
	PROLOGUE(C_SYMBOL_NAME(__mpn_sub_nc))
	pushl %edi
	pushl %esi

	movl 12(%esp),%edi		/* res_ptr */
	movl 16(%esp),%esi		/* s1_ptr */
	movl 20(%esp),%edx		/* s2_ptr */
	movl 24(%esp),%ecx		/* size */

	movl	%ecx,%eax
	shrl	$3,%ecx			/* compute count for unrolled loop */
	negl	%eax
	andl	$7,%eax			/* get index where to start loop */
	jz	Loopgo			/* necessary special case for 0 */
	incl	%ecx			/* adjust loop count */
	shll	$2,%eax			/* adjustment for pointers... */
	subl	%eax,%edi		/* ... since they are offset ... */
	subl	%eax,%esi		/* ... by a constant when we ... */
	subl	%eax,%edx		/* ... enter the loop */
	shrl	$2,%eax			/* restore previous value */
#ifdef PIC
/* Calculate start address in loop for PIC.  Due to limitations in some
   assemblers, Loop-L0a-3 cannot be put into the leal */
	call	L0a
L0a:	leal	(%eax,%eax,8),%eax
	addl	(%esp),%eax
	addl	$(Loop-L0a-3),%eax
	addl	$4,%esp
#else
/* Calculate start address in loop for non-PIC.  */
 	leal	Loop-3(%eax,%eax,8),%eax
#endif
/* These lines initialize carry from the 5th parameter.  Should be possible to
   simplify.  */
	pushl	%ebp
	movl	32(%esp),%ebp
	shrl	$1,%ebp			/* shift bit 0 into carry */
	popl	%ebp

	jmp	*%eax			/* jump into loop */

	ALIGN (3)
	.globl C_SYMBOL_NAME(__mpn_sub_n)
C_SYMBOL_NAME(__mpn_sub_n:)
	PROLOGUE(C_SYMBOL_NAME(__mpn_sub_n))
	pushl %edi
	pushl %esi

	movl 12(%esp),%edi		/* res_ptr */
	movl 16(%esp),%esi		/* s1_ptr */
	movl 20(%esp),%edx		/* s2_ptr */
	movl 24(%esp),%ecx		/* size */

	movl	%ecx,%eax
	shrl	$3,%ecx			/* compute count for unrolled loop */
	negl	%eax
	andl	$7,%eax			/* get index where to start loop */
	jz	Loop			/* necessary special case for 0 */
	incl	%ecx			/* adjust loop count */
	shll	$2,%eax			/* adjustment for pointers... */
	subl	%eax,%edi		/* ... since they are offset ... */
	subl	%eax,%esi		/* ... by a constant when we ... */
	subl	%eax,%edx		/* ... enter the loop */
	shrl	$2,%eax			/* restore previous value */
#ifdef PIC
/* Calculate start address in loop for PIC.  Due to limitations in some
   assemblers, Loop-L0b-3 cannot be put into the leal */
	call	L0b
L0b:	leal	(%eax,%eax,8),%eax
	addl	(%esp),%eax
	addl	$(Loop-L0b-3),%eax
	addl	$4,%esp
#else
/* Calculate start address in loop for non-PIC.  */
 	leal	Loop-3(%eax,%eax,8),%eax
#endif
	jmp	*%eax			/* jump into loop */

Loopgo:	pushl	%ebp
	movl	32(%esp),%ebp
	shrl	$1,%ebp			/* shift bit 0 into carry */
	popl	%ebp

	ALIGN (3)
Loop:	movl	(%esi),%eax
	sbbl	(%edx),%eax
	movl	%eax,(%edi)
	movl	4(%esi),%eax
	sbbl	4(%edx),%eax
	movl	%eax,4(%edi)
	movl	8(%esi),%eax
	sbbl	8(%edx),%eax
	movl	%eax,8(%edi)
	movl	12(%esi),%eax
	sbbl	12(%edx),%eax
	movl	%eax,12(%edi)
	movl	16(%esi),%eax
	sbbl	16(%edx),%eax
	movl	%eax,16(%edi)
	movl	20(%esi),%eax
	sbbl	20(%edx),%eax
	movl	%eax,20(%edi)
	movl	24(%esi),%eax
	sbbl	24(%edx),%eax
	movl	%eax,24(%edi)
	movl	28(%esi),%eax
	sbbl	28(%edx),%eax
	movl	%eax,28(%edi)
	leal	32(%edi),%edi
	leal	32(%esi),%esi
	leal	32(%edx),%edx
	decl	%ecx
	jnz	Loop

	sbbl	%eax,%eax
	negl	%eax

	popl %esi
	popl %edi
	ret
	EPILOGUE(C_SYMBOL_NAME(__mpn_sub_nc))
	EPILOGUE(C_SYMBOL_NAME(__mpn_sub_n))