minix/lib/libc/arch/m68k/string/memccpy.S
Ben Gras 2fe8fb192f Full switch to clang/ELF. Drop ack. Simplify.
There is important information about booting non-ack images in
docs/UPDATING. ack/aout-format images can't be built any more, and
booting clang/ELF-format ones is a little different. Updating to the
new boot monitor is recommended.

Changes in this commit:

	. drop boot monitor -> allowing dropping ack support
	. facility to copy ELF boot files to /boot so that old boot monitor
	  can still boot fairly easily, see UPDATING
	. no more ack-format libraries -> single-case libraries
	. some cleanup of OBJECT_FMT, COMPILER_TYPE, etc cases
	. drop several ack toolchain commands, but not all support
	  commands (e.g. aal is gone but acksize is not yet).
	. a few libc files moved to netbsd libc dir
	. new /bin/date as minix date used code in libc/
	. test compile fix
	. harmonize includes
	. /usr/lib is no longer special: without ack, /usr/lib plays no
	  kind of special bootstrapping role any more and bootstrapping
	  is done exclusively through packages, so releases depend even
	  less on the state of the machine making them now.
	. rename nbsd_lib* to lib*
	. reduce mtree
2012-02-14 14:52:02 +01:00

82 lines
2.9 KiB
ArmAsm

/* $NetBSD: memccpy.S,v 1.1 2001/02/05 00:17:22 scottr Exp $ */
/*
* Copyright (C) 1999 Scott Reynolds. 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. 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.
*/
#include <machine/asm.h>
#if defined(LIBC_SCCS) && !defined(lint)
RCSID("$NetBSD: memccpy.S,v 1.1 2001/02/05 00:17:22 scottr Exp $")
#endif /* LIBC_SCCS and not lint */
ENTRY(memccpy)
movl %sp@(16),%d0 | count
jeq Lmcbail | nothing to do
movl %sp@(4),%a0 | a0 = toaddr
subql #1,%d0 | prepare count for DBcc loop
movl %sp@(8),%a1 | a1 = fromaddr
movl %sp@(12),%d1 | d1 = terminator
jeq Lmcloop | handle ASCII NUL specially
movl %d2,%sp@- | save scratch register
Lmcnzloop:
movb %a1@+,%d2 | move a byte
movb %d2,%a0@+
cmpb %d2,%d1 | found the terminator?
dbeq %d0,Lmcnzloop | if not, keep transferring,
jeq Lmcnzdone | otherwise done
clrw %d0 | check to see if more to do
subql #1,%d0
jcc Lmcnzloop | yes, keep going...
movl %sp@+,%d2 | restore scratch register
movql #0,%d0 | no terminator found, return NULL
#ifdef __SVR4_ABI__
movl %d0,%a0 | XXX maybe use lea to avoid stall?
#endif
rts
Lmcloop:
movb %a1@+,%a0@+ | move a byte; was it NUL?
dbeq %d0,Lmcloop | if not, keep transferring,
jeq Lmcdone | otherwise done
clrw %d0 | check to see if more to do
subql #1,%d0
jcc Lmcloop | yes, keep going...
| Note: %d0 is now -1!
movql #0,%d0 | no terminator found, return NULL
Lmcbail:
#ifdef __SVR4_ABI__
movl %d0,%a0 | XXX maybe use lea to avoid stall?
#endif
rts
Lmcnzdone:
movl %sp@+,%d2 | restore scratch register
Lmcdone:
movl %a0,%d0
rts