x86_64/gen/swapcontext.S

1.7  riastrad /*	$NetBSD: swapcontext.S,v 1.7 2025/05/03 19:56:21 riastradh Exp $	*/
1.1      fvdl
1.1      fvdl /*
1.1      fvdl  * Copyright (c) 2003 Wasabi Systems, Inc.
1.1      fvdl  * All rights reserved.
1.1      fvdl  *
1.1      fvdl  * Written by Frank van der Linden for Wasabi Systems, Inc.
1.1      fvdl  *
1.1      fvdl  * Redistribution and use in source and binary forms, with or without
1.1      fvdl  * modification, are permitted provided that the following conditions
1.1      fvdl  * are met:
1.1      fvdl  * 1. Redistributions of source code must retain the above copyright
1.1      fvdl  *    notice, this list of conditions and the following disclaimer.
1.1      fvdl  * 2. Redistributions in binary form must reproduce the above copyright
1.1      fvdl  *    notice, this list of conditions and the following disclaimer in the
1.1      fvdl  *    documentation and/or other materials provided with the distribution.
1.1      fvdl  * 3. All advertising materials mentioning features or use of this software
1.1      fvdl  *    must display the following acknowledgement:
1.1      fvdl  *      This product includes software developed for the NetBSD Project by
1.1      fvdl  *      Wasabi Systems, Inc.
1.1      fvdl  * 4. The name of Wasabi Systems, Inc. may not be used to endorse
1.1      fvdl  *    or promote products derived from this software without specific prior
1.1      fvdl  *    written permission.
1.1      fvdl  *
1.1      fvdl  * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND
1.1      fvdl  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
1.1      fvdl  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
1.1      fvdl  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL WASABI SYSTEMS, INC
1.1      fvdl  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
1.1      fvdl  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
1.1      fvdl  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
1.1      fvdl  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
1.1      fvdl  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
1.1      fvdl  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
1.1      fvdl  * POSSIBILITY OF SUCH DAMAGE.
1.1      fvdl  */
1.1      fvdl
1.1      fvdl #include <machine/asm.h>
1.1      fvdl
1.1      fvdl #if defined(LIBC_SCCS) && !defined(lint)
1.7  riastrad 	RCSID("$NetBSD: swapcontext.S,v 1.7 2025/05/03 19:56:21 riastradh Exp $")
1.1      fvdl #endif /* LIBC_SCCS && !lint */
1.1      fvdl
1.1      fvdl /*
1.1      fvdl  * 56 == offsetof(ucontext_t, uc_mcontext)
1.1      fvdl  * 21 == _REG_RIP
1.1      fvdl  * 24 == _REG_URSP
1.1      fvdl  */
1.1      fvdl
1.1      fvdl ENTRY(swapcontext)
1.4     pooka 	pushq	%rdi				/* preserve oucp */
1.4     pooka 	pushq	%rsi				/* preserve ucp */
1.2    kleink 	call	PIC_PLT(_C_LABEL(_getcontext))
1.4     pooka 	popq	%rsi
1.4     pooka 	popq	%rdi
1.1      fvdl 	testl	%eax,%eax
1.1      fvdl 	jnz	2f
1.4     pooka 	movq	0(%rsp),%r11
1.4     pooka 	movq	%r11,(56 + 21 * 8)(%rdi)
1.4     pooka 	leaq	8(%rsp),%r11
1.4     pooka 	movq	%r11,(56 + 24 * 8)(%rdi)
1.4     pooka 	movq	%rsi,%rdi
1.1      fvdl 	call	PIC_PLT(_C_LABEL(setcontext))
1.1      fvdl 2:
1.1      fvdl 	ret
1.6  uebayasi END(swapcontext)