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/* crt0-efi-ia32.S - x86 EFI startup code.
   Copyright (C) 1999 Hewlett-Packard Co.
    Contributed by David Mosberger <davidm@hpl.hp.com>.

   This file is part of GNU-EFI, the GNU EFI development environment.

   GNU EFI is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2, or (at your option)
   any later version.

   GNU EFI is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with GNU EFI; see the file COPYING.  If not, write to the Free
   Software Foundation, 59 Temple Place - Suite 330, Boston, MA
   02111-1307, USA. */

    .text
    .align 4

    .globl _start
_start:
    pushl %ebp
    movl %esp,%ebp

    pushl 12(%ebp)          # copy "image" argument
    pushl  8(%ebp)          # copy "systab" argument

    call 0f
0:  popl %eax
    movl %eax,%ebx

    addl $ImageBase-0b,%eax     # %eax = ldbase
    addl $_DYNAMIC-0b,%ebx      # %ebx = _DYNAMIC

    pushl %ebx          # pass _DYNAMIC as second argument
    pushl %eax          # pass ldbase as first argument
    call _relocate
    popl %ebx
    popl %ebx
    testl %eax,%eax
    jne .exit
  
    call efi_main           # call app with "image" and "systab" argument

.exit:  leave
    ret
 
    // hand-craft a dummy .reloc section so EFI knows it's a relocatable executable:
 
    .data
dummy:  .long   0

#define IMAGE_REL_ABSOLUTE  0
    .section .reloc, "a"
    .long   dummy                   // Page RVA
    .long   10                  // Block Size (2*4+2)
    .word   (IMAGE_REL_ABSOLUTE<<12) +  0       // reloc for dummy