reactos/ntoskrnl/kdbg/i386/setjmp.S

   1         .file   "setjmp.S"
   2 /*
   3  * Copyright (C) 1998, 1999, Jonathan S. Shapiro.
   4  *
   5  * This file is part of the EROS Operating System.
   6  *
   7  * This program is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU General Public License
   9  * as published by the Free Software Foundation; either version 2,
  10  * or (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License
  18  * along with this program; if not, write to the Free Software
  19  * Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  20  */
  21
  22 /* #include <eros/i486/asm.h> */
  23
  24
  25         /*
  26          * typedef struct {
  27          *  unsigned long ebx, esi, edi;
  28          *  unsigned long ebp;
  29          *  unsigned long sp;
  30          *  unsigned long pc;
  31          * } jmp_buf[1];
  32          */
  33
  34         /*
  35          * On entry, the stack to setjmp looks like:
  36          *
  37          *     ptr to jmp_buf
  38          *     return PC
  39          */
  40 .globl _setjmp
  41 _setjmp:
  42         pushl   %ebp
  43         movl    %esp,%ebp
  44
  45         movl    0x8(%ebp),%eax          /* address of jmp_buf to eax */
  46         movl    %ebx,(%eax)             /* save %ebx */
  47         movl    %esi,4(%eax)            /* save %esi */
  48         movl    %edi,8(%eax)            /* save %edi */
  49         leal    8(%ebp),%edx            /* calling proc's esp, not ours! */
  50         movl    %edx,16(%eax)
  51         movl    4(%ebp), %edx           /* save return PC */
  52         movl    %edx,20(%eax)
  53         movl    0(%ebp),%edx            /* calling proc's ebp, not ours! */
  54         movl    %edx,12(%eax)
  55
  56         xorl    %eax,%eax               /* return 0 the first time */
  57         leave
  58         ret     $4
  59