1 #ident "$Id: entry.S,v 1.3 2004/12/21 02:47:08 hpa Exp $"
2 # -----------------------------------------------------------------------
4 # Copyright 2003-2004 H. Peter Anvin - All Rights Reserved
6 # Permission is hereby granted, free of charge, to any person
7 # obtaining a copy of this software and associated documentation
8 # files (the "Software"), to deal in the Software without
9 # restriction, including without limitation the rights to use,
10 # copy, modify, merge, publish, distribute, sublicense, and/or
11 # sell copies of the Software, and to permit persons to whom
12 # the Software is furnished to do so, subject to the following
15 # The above copyright notice and this permission notice shall
16 # be included in all copies or substantial portions of the Software.
18 # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
19 # EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
20 # OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
21 # NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
22 # HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
23 # WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
24 # FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
25 # OTHER DEALINGS IN THE SOFTWARE.
27 # -----------------------------------------------------------------------
29 # COM32 start up code - must be linked first in the binary
34 .type _start, @function
36 # This first instruction acts as COM32 magic number
39 # Upwards string operations
42 # Zero the .bss segment
44 movl $__bss_start,%edi # Symbol provided by linker
45 movl $_end+3,%ecx # Symbol provided by linker
50 # Copy COM32 invocation parameters
51 leal 4(%esp),%esi # Argument list
54 movl %esp,-4(%edi) # Save the initial stack ptr
60 # Parse the command line (assumes REGPARM)
61 movl __com32+4,%edx # Command line
62 pushl %edx # Make space for argv
65 pushl %eax # Save argc
67 # Look for library initialization functions
68 movl $__ctors_start, %esi
70 cmpl $__ctors_end, %esi
76 # Actually run main. This assumes REGPARM is used!!!!
82 call *(__exit_handler)
84 .size _start, .-_start