kern/switch_i386.s

   1 /*!
   2  * \file
   3  * <!--
   4  * Copyright 2004 Develer S.r.l. (http://www.develer.com/)
   5  * Copyright 1999,2000,2001 Bernardo Innocenti <bernie@develer.com>
   6  * This file is part of DevLib - See devlib/README for information.
   7  * -->
   8  *
   9  * \brief i386 context switch
  10  *
  11  * \version $Id$
  12  *
  13  * \author Bernardo Innocenti <bernie@develer.com>
  14  */
  15
  16 /* void asm_switch_context(void ** new_sp, void ** save_sp) */
  17 .globl asm_switch_context
  18 asm_switch_context:
  19         pushl   %eax
  20         pushl   %ebx
  21         pushl   %ecx
  22         pushl   %edx
  23         pushl   %esi
  24         pushl   %edi
  25         pushl   %ebp
  26         movl    0x24(%esp),%ebp         /* ebp = save_sp */
  27         movl    %esp,(%ebp)             /* *save_sp = esp */
  28         movl    0x20(%esp),%ebp         /* ebp = new_sp */
  29         movl    (%ebp),%esp             /* esp = *new_sp */
  30         popl    %ebp
  31         popl    %edi
  32         popl    %esi
  33         popl    %edx
  34         popl    %ecx
  35         popl    %ebx
  36         popl    %eax
  37         ret
  38
  39 /* int asm_switch_version(void) */
  40 .globl asm_switch_version
  41 asm_switch_version:
  42         mov     $1,%eax
  43         ret
  44