root/usr/src/cmd/mdb/intel/amd64/libstand/setjmp.S
/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License, Version 1.0 only
 * (the "License").  You may not use this file except in compliance
 * with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */
/*
 * Copyright 2004 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

#if defined(__lint)
#include <setjmp.h>
#endif

#include <sys/asm_linkage.h>

/*
 *      longjmp(env, val)
 * will generate a "return(val)" from
 * the last call to
 *      setjmp(env)
 * by restoring registers rip rsp rbp rbx r12 r13 r14 r15 from 'env'
 * and doing a return.
 *
 * entry    reg   offset
 * env[0] = %rbx  0     register variables
 * env[1] = %r12  8
 * env[2] = %r13  16
 * env[3] = %r14  24
 * env[4] = %r15  32
 * env[5] = %rbp  40    stack frame
 * env[6] = %rsp  48
 * env[7] = %rip  56
 */

#if defined(__lint)
/*ARGSUSED*/
int
setjmp(jmp_buf env)
{
        return (0);
}

/*ARGSUSED*/
int
sigsetjmp(sigjmp_buf env, int savemask)
{
        return (0);
}
#else   /* __lint */

        ENTRY(setjmp)
        ALTENTRY(sigsetjmp)
        movq    %rbx, 0(%rdi)
        movq    %r12, 8(%rdi)
        movq    %r13, 16(%rdi)
        movq    %r14, 24(%rdi)
        movq    %r15, 32(%rdi)
        movq    %rbp, 40(%rdi)
        popq    %rdx            /* return address */
        movq    %rsp, 48(%rdi)
        movq    %rdx, 56(%rdi)
        xorl    %eax, %eax      /* return 0 */
        jmp     *%rdx
        SET_SIZE(sigsetjmp)
        SET_SIZE(setjmp)

#endif  /* __lint */

#if defined(__lint)
/*ARGSUSED*/
void
longjmp(jmp_buf env, int val)
{
}

/*ARGSUSED*/
void
siglongjmp(sigjmp_buf env, int val)
{
}
#else   /* __lint */

        ENTRY(longjmp)
        ALTENTRY(siglongjmp)
        movq    0(%rdi), %rbx
        movq    8(%rdi), %r12
        movq    16(%rdi), %r13
        movq    24(%rdi), %r14
        movq    32(%rdi), %r15
        movq    40(%rdi), %rbp
        movq    48(%rdi), %rsp
        movl    %esi, %eax
        test    %eax, %eax      /* if val != 0          */
        jnz     1f              /*      return val      */
        incl    %eax            /* else return 1        */
1:
        movq    56(%rdi), %rdx  /* return to caller of setjmp */
        jmp     *%rdx
        SET_SIZE(siglongjmp)
        SET_SIZE(longjmp)

#endif  /* __lint */