/*      $NetBSD: setjmp.S,v 1.19 2025/05/03 19:55:32 riastradh Exp $    */

/*-
 * Copyright (c) 1990 The Regents of the University of California.
 * All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * William Jolitz.
 *
 * 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: @(#)setjmp.s      5.1 (Berkeley) 4/23/90
 */

#include <machine/asm.h>
#if defined(LIBC_SCCS)
        RCSID("$NetBSD: setjmp.S,v 1.19 2025/05/03 19:55:32 riastradh Exp $")
#endif

/*
 * 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.
 * The previous signal state is restored.
 */

/*
 * setjmp(jmp_buf env@esp[4,8))
 *
 * ELF symbol: __setjmp14, because the size of jmp_buf changed on some
 * platforms in 1.4.
 */
ENTRY(__setjmp14)
        /*
         * Save the callee-saves registers: %ebp, %ebx, %edi, %esi,
         * plus %esp and the return address on the stack since it
         * will be overwritten if the caller makes any subroutine
         * calls before longjmp.
         */
        movl    4(%esp),%ecx            /* ecx := env */
        movl    0(%esp),%edx            /* edx := return address */
        movl    %edx,0(%ecx)
        movl    %ebx,4(%ecx)
        movl    %esp,8(%ecx)
        movl    %ebp,12(%ecx)
        movl    %esi,16(%ecx)
        movl    %edi,20(%ecx)

        /* Get the signal mask. */
        leal    24(%ecx),%edx

        PIC_PROLOGUE
        pushl   %edx                    /* oset (signal mask saved to) */
        pushl   $0                      /* set := NULL */
        pushl   $0                      /* how := 0 (ignored) */
        call    PIC_PLT(_C_LABEL(__sigprocmask14))
        addl    $12,%esp                /* pop sigprocmask args */
        PIC_EPILOGUE

        xorl    %eax,%eax               /* return 0 first time around */
        ret
END(__setjmp14)

/*
 * longjmp(jmp_buf env@esp[4,8), int val@[8,12))
 *
 * ELF symbol: __longjmp14, because the size of jmp_buf changed on some
 * platforms in 1.4.
 */
ENTRY(__longjmp14)
        /*
         * Restore the callee-saves registers: %ebp, %ebx, %edi, %esi,
         * plus %esp and the return address on the stack.
         */
        movl    4(%esp),%edx            /* edx := env */
        movl    8(%esp),%eax            /* eax := val */
        movl    0(%edx),%ecx            /* ecx := return address */
        movl    4(%edx),%ebx
        movl    8(%edx),%esp
        movl    12(%edx),%ebp
        movl    16(%edx),%esi
        movl    20(%edx),%edi
        movl    %ecx,0(%esp)            /* restore return address */

        /* Restore the signal mask. */
        leal    24(%edx),%edx

        pushl   %eax                    /* save val@eax */

        PIC_PROLOGUE
        pushl   $0                      /* oset := NULL */
        pushl   %edx                    /* set (signal mask restored from) */
        pushl   $3                      /* how := SIG_SETMASK */
        call    PIC_PLT(_C_LABEL(__sigprocmask14))
        addl    $12,%esp                /* pop sigprocmask args */
        PIC_EPILOGUE

        popl    %eax                    /* restore val@eax */

        testl   %eax,%eax               /* val == 0? */
        jz      3f                      /* jump if val == 0 */
        ret                             /* return val@eax */

3:      incl    %eax                    /* val@eax := 1 */
        ret                             /* return val@eax */
END(__longjmp14)