NetBSD/sys/lib/libkern/i386/strcpy.S
1994-02-15 13:42:30 +00:00

96 lines
2.8 KiB
ArmAsm

/*
* Copyright (c) 1993,94 Winning Strategies, Inc.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by Winning Strategies, Inc.
* 4. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* $Id: strcpy.S,v 1.3 1994/02/15 13:42:33 mycroft Exp $
*/
#if defined(LIBC_SCCS)
.text
.asciz "$Id: strcpy.S,v 1.3 1994/02/15 13:42:33 mycroft Exp $"
#endif
#include "DEFS.h"
/*
* strcpy (dst, src)
* copy the string src to dst.
*
* Written by:
* J.T. Conklin (jtc@wimsey.com), Winning Strategies, Inc.
*/
/*
* I've unrolled the loop eight times: large enough to make a
* significant difference, and small enough not to totally trash the
* cache.
*/
ENTRY(strcpy)
movl 4(%esp),%ecx /* dst address */
movl 8(%esp),%edx /* src address */
pushl %ecx /* push dst address */
.align 2,0x90
L1: movb (%edx),%al /* unroll loop, but not too much */
movb %al,(%ecx)
testb %al,%al
jz L2
movb 1(%edx),%al
movb %al,1(%ecx)
testb %al,%al
jz L2
movb 2(%edx),%al
movb %al,2(%ecx)
testb %al,%al
jz L2
movb 3(%edx),%al
movb %al,3(%ecx)
testb %al,%al
jz L2
movb 4(%edx),%al
movb %al,4(%ecx)
testb %al,%al
jz L2
movb 5(%edx),%al
movb %al,5(%ecx)
testb %al,%al
jz L2
movb 6(%edx),%al
movb %al,6(%ecx)
testb %al,%al
jz L2
movb 7(%edx),%al
movb %al,7(%ecx)
addl $8,%edx
addl $8,%ecx
testb %al,%al
jnz L1
L2: popl %eax /* pop dst address */
ret