minix/lib/nbsd_libc/arch/m68k/gen/resumecontext.S
Gianluca Guida b6cbf7203b Import unmodified NetBSD libc in trunk
This patch imports the unmodified current version of NetBSD libc.
The NetBSD includes are in /nbsd_include, while the libc code itself is 
split between lib/nbsd_libc and common/lib/libc.
2011-02-14 19:36:03 +00:00

59 lines
2.3 KiB
ArmAsm

/* $NetBSD: resumecontext.S,v 1.5 2008/04/28 20:22:56 martin Exp $ */
/*-
* Copyright (c) 2001 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Klaus Klein.
*
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``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 FOUNDATION OR CONTRIBUTORS
* 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: resumecontext.S,v 1.5 2008/04/28 20:22:56 martin Exp $")
#endif /* LIBC_SCCS && !lint */
/*
* This assembly-language implementation differs from the (obvious)
* C-language implementation only in not clobbering the previous
* function's return address (us), which is the point of the exercise.
*/
ENTRY(_resumecontext)
subl #(4 + 1024),%sp /* retaddr preservation + ucontext_t */
lea %sp@,%a0
movl %a0,%sp@-
jbsr PIC_PLT(_C_LABEL(_getcontext))
movl %sp@(4 + 4),%sp@ /* uc_link */
tstl %sp@ /* check for NULL */
jne 1f
jbsr PIC_PLT(_C_LABEL(exit)) /* cleanly exit(0) */
jmp 2f
1: jbsr PIC_PLT(_C_LABEL(setcontext))
/* NOTREACHED */
/* But just in case... */
2: movl #-1,%sp@
jbsr PIC_PLT(_C_LABEL(_exit))
/* NOTREACHED */