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/*
* Copyright (c) 1994-1998 University of Utah and the Flux Group.
* All rights reserved.
*
* This file is part of the Flux OSKit. The OSKit is free software, also known
* as "open source;" you can redistribute it and/or modify it under the terms
* of the GNU General Public License (GPL), version 2, as published by the Free
* Software Foundation (FSF). To explore alternate licensing terms, contact
* the University of Utah at csl-dist@cs.utah.edu or +1-801-585-3271.
*
* The OSKit 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 GPL for more details. You should have
* received a copy of the GPL along with the OSKit; see the file COPYING. If
* not, write to the FSF, 59 Temple Place #330, Boston, MA 02111-1307, USA.
*/
/*
* Mach Operating System
* Copyright (c) 1992,1991,1990,1989 Carnegie Mellon University
* All Rights Reserved.
*
* Permission to use, copy, modify and distribute this software and its
* documentation is hereby granted, provided that both the copyright
* notice and this permission notice appear in all copies of the
* software, derivative works or modified versions, and any portions
* thereof, and that both notices appear in supporting documentation.
*
* CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
* CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
* ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
*
* Carnegie Mellon requests users of this software to return to
*
* Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
* School of Computer Science
* Carnegie Mellon University
* Pittsburgh PA 15213-3890
*
* any improvements or extensions that they make and grant Carnegie Mellon
* the rights to redistribute these changes.
*/
#include <oskit/x86/asm.h>
#if 0 /* is this useful? */
/* l2rbcopy(from, to, bcount) */
ENTRY(l2rbcopy)
pushl %ebp
movl %esp,%ebp
pushl %edi
pushl %esi
movl B_ARG2,%edx
movl B_ARG1,%edi
movl B_ARG0,%esi
/* move longs */
0: cld
movl %edx,%ecx
sarl $2,%ecx
js 1f
rep
movsl
/* move bytes */
movl %edx,%ecx
andl $3,%ecx
rep
movsb
1:
popl %esi
popl %edi
leave
ret
#endif
/*
* bcopy - like l2rbcopy, but recognizes overlapping ranges and handles
* them correctly.
* bcopy(from, to, bytes)
* char *from, *to;
* int bytes;
*/
ENTRY(bcopy)
pushl %ebp
movl %esp,%ebp
pushl %edi
pushl %esi
movl B_ARG0,%esi
movl B_ARG1,%edi
bcopy_common:
movl B_ARG2,%edx
leal (%esi,%edx), %eax /* from + bytes */
cmpl %eax, %edi /* <= to */
jae 0f
leal (%edi,%edx), %eax /* to + bytes */
cmpl %eax, %esi /* <= from */
jae 0f
cmpl %esi, %edi /* from > to */
jb 0f
je 1f
addl %edx, %esi; decl %esi
addl %edx, %edi; decl %edi
std
movl %edx,%ecx
/* move bytes backwards */
rep
movsb
cld
1:
/* memcpy: return dest pointer */
movl B_ARG0,%eax
popl %esi
popl %edi
leave
ret
/* move words forwards */
0: cld
movl %edx,%ecx
sarl $2,%ecx
js 2f
rep
movsl
/* move bytes forwards */
movl %edx,%ecx
andl $3,%ecx
rep
movsb
2:
/* memcpy: return dest pointer */
movl B_ARG0,%eax
popl %esi
popl %edi
leave
ret
/* memcpy(to, from, count) */
/*
* memmove is just memcpy that deals with overlapping regions. Since
* our memcpy does that anyway, it's just an alternate entry point for
* it.
*/
ENTRY2(memcpy, memmove)
pushl %ebp
movl %esp,%ebp
pushl %edi
pushl %esi
movl B_ARG0,%edi
movl B_ARG1,%esi
jmp bcopy_common
#ifdef __ELF__
/*
* Since this file defines both bcopy and memcpy, a file in
* another library defining just bcopy will conflict with
* this file when linked in later to define memcpy (or vice versa).
* In ELF, we can avoid this probably easily using weak symbols.
*/
.weak bcopy
.weak memcpy
.weak memmove
#endif
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