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# -----------------------------------------------------------------------
#
# Copyright 2003-2008 H. Peter Anvin - All Rights Reserved
#
# Permission is hereby granted, free of charge, to any person
# obtaining a copy of this software and associated documentation
# files (the "Software"), to deal in the Software without
# restriction, including without limitation the rights to use,
# copy, modify, merge, publish, distribute, sublicense, and/or
# sell copies of the Software, and to permit persons to whom
# the Software is furnished to do so, subject to the following
# conditions:
#
# The above copyright notice and this permission notice shall
# be included in all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
# OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
# HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
# WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
# FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
# OTHER DEALINGS IN THE SOFTWARE.
#
# -----------------------------------------------------------------------
# COM32 start up code - must be linked first in the binary
.section ".text","ax"
.globl _start
_start:
# This first instruction acts as COM32 magic number
movl $0x21cd4cff,%eax
# Upwards string operations
cld
# Zero the .bss segment
xorl %eax,%eax
movl $__bss_start,%edi # Symbol provided by linker
movl $_end+3,%ecx # Symbol provided by linker
subl %edi,%ecx
shrl $2,%ecx
rep ; stosl
# Copy COM32 invocation parameters
leal 4(%esp),%esi # Argument list
movl $__com32,%edi
movl $6,%ecx
movl %esp,-4(%edi) # Save the initial stack ptr
cmpl (%esi),%ecx
jbe 1f
movl (%esi),%ecx
1: rep ; movsl
# Run program; we call this __start rather than main since we
# did not parse the command line or anything like that.
jmp __start
.section ".bss","aw"
.globl __entry_esp
__entry_esp: .space 4
.globl __com32
__com32: .space 4*6
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