/*      $NetBSD: contextspfunc.S,v 1.2 2025/04/21 12:06:08 riastradh Exp $      */

/*-
* Copyright (c) 2025 The NetBSD Foundation, 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.
*
* 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.
*/

#define _LOCORE

#include <machine/asm.h>

RCSID("$NetBSD: contextspfunc.S,v 1.2 2025/04/21 12:06:08 riastradh Exp $")

/*
* contextspfunc()
*
*      makecontext(3) function.  Store the stack pointer on entry at
*      the global variable contextsp and call contextdone.
*/
LEAF_ENTRY(contextspfunc)
       addil   LT%_C_LABEL(contextdone), %r19  /* r20 := contextdone */
       ldw     RT%_C_LABEL(contextdone)(%r1), %r20
       addil   LT%_C_LABEL(contextsp), %r19    /* r21 := &contextsp */
       ldw     RT%_C_LABEL(contextsp)(%r1), %r21
       bv      %r0(%r20)                       /* jump to contextdone */
        stw    %sp, 0(%r21)                    /* contextsp := sp */
EXIT(contextspfunc)