/*      $NetBSD: compat_setjmp.S,v 1.1 2005/10/15 22:11:22 uwe Exp $    */

/*
 * Copyright (c) 1992, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * This software was developed by the Computer Systems Engineering group
 * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
 * contributed to Berkeley.
 *
 * 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. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
 *
 * from: Header: setjmp.s,v 1.2 92/06/25 03:18:43 torek Exp
 */

#include <machine/asm.h>
#if defined(LIBC_SCCS) && !defined(lint)
#if 0
        .asciz "@(#)setjmp.s    8.1 (Berkeley) 6/4/93"
#else
        RCSID("$NetBSD: compat_setjmp.S,v 1.1 2005/10/15 22:11:22 uwe Exp $")
#endif
#endif /* LIBC_SCCS and not lint */

/*
 * C library -- setjmp, longjmp
 *
 *      longjmp(a,v)
 * will generate a "return(v)" from
 * the last call to
 *      setjmp(a)
 * by restoring registers from the stack,
 * and a struct sigcontext, see <signal.h>
 */

#include "SYS.h"

ENTRY(setjmp)
        /*
         * We use the caller's `arg dump' area (%sp+0x44; there are 6 ints
         * reserved there for us) to avoid having to allocate stack space
         * here.
         */
        mov     %o0, %o2        /* build sigcontext in [%o2] */
        mov     1, %o0          /* SIG_BLOCK */
        mov     SYS_compat_13_sigprocmask13, %g1
        clr     %o1             /* sigprocmask(SIG_BLOCK, (sigset_t *)NULL) */
        t       ST_SYSCALL
        st      %o0, [%o2 + 4]  /* sc.sc_mask = current mask; */
        mov     SYS___sigaltstack14, %g1
        clr     %o0             /* sigaltstack(NULL, &foo) */
        add     %sp, 0x48, %o1  /* (foo being in arg dump area) */
        t       ST_SYSCALL
        ld      [%sp + 0x50], %o0       /* foo.ss_flags */
        and     %o0, 1, %o1     /* onstack = foo.ss_flags & 1; */
        st      %o0, [%o2 + 0]  /* sc.sc_onstack = current onstack; */
        st      %sp, [%o2 + 8]  /* sc.sc_sp = sp (both ours and caller's) */
        add     %o7, 8, %o0
        st      %o0, [%o2 + 12] /* sc.sc_pc = return_pc */
        add     %o7, 12, %o0
        st      %o0, [%o2 + 16] /* sc.sc_npc = return_pc + 4 */
        st      %g0, [%o2 + 20] /* sc.sc_psr = (clean psr) */
        st      %fp, [%o2 + 24] /* sc.sc_g1 = %fp (misuse, but what the heck) */
                                /* sc.sc_o0 = random(), set in longjmp */
        retl                    /* return 0 */
         clr    %o0

/*
 * All we need to do here is force sigreturn to load a new stack pointer,
 * new <pc,npc>, and appropriate %o0 return value from the sigcontext built
 * in setjmp.  The %i and %l registers will be reloaded from the place to
 * which %sp points, due to sigreturn() semantics (sigreturn does not modify
 * the window pointer in the psr, hence it must force all windows to reload).
 */
ENTRY(longjmp)
        save    %sp, -96, %sp
        ld      [%i0 + 8], %o2  /* make sure sc->sc_sp, sc->sc_fp nonzero */
        ld      [%i0 + 24], %o3
        orcc    %o2, %o3, %g0
        bz      Lbotch
         tst    %i1             /* if (v == 0) v = 1; */
        bz,a    1f
         mov    1, %i1
1:
        st      %i1, [%i0 + 28] /* sc.sc_o0 = v; */
        mov     SYS_compat_13_sigreturn13, %g1
        mov     %i0, %o0
        t       ST_SYSCALL      /* sigreturn(scp); */

Lbotch:
        /* oops, caller botched it */
        call    _C_LABEL(longjmperror)
         nop
        unimp   0