1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
|
/* Startup code compliant to the ELF MN10300 ABI.
Copyright (C) 1995,1996,1997,1998,2000,2001 Free Software Foundation, Inc.
Contributed by Alexandre Oliva <aoliva@redhat.com>
Based on ../../i386/elf/start.S.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
/* This is the canonical entry point, usually the first thing in the text
segment. The SVR4/i386 ABI (pages 3-31, 3-32) says that when the entry
point runs, most registers' values are unspecified, except for:
a0 Contains a function pointer to be registered with `atexit'.
This is how the dynamic linker arranges to have DT_FINI
functions called for shared libraries that have been loaded
before this code runs.
sp The stack contains the arguments and environment:
(4,sp) argc
(8,sp) argv[0]
...
(4*(argc+1),sp) NULL
(4*(argc+2),sp) envp[0]
...
NULL
*/
#include "bp-sym.h"
.text
.globl _start
.type _start,@function
_start:
/* Extract the arguments as encoded on the stack and set up
the arguments for `main': argc, argv. envp will be determined
later in __libc_start_main. */
mov sp,a3
add -32,sp
mov a3,(28,sp) /* stack_end. */
mov d0,(24,sp) /* rtld_fini. */
mov _fini, d3
mov d3,(20,sp) /* fini. */
mov _init, d2
mov d2,(16,sp) /* init. */
inc4 a3
mov a3,(12,sp) /* argv. */
/* Set the initial frame pointer as 0, so that the bottom of
the stack is clearly marked. */
mov 0,a3
mov (32,sp), d1 /* argc. */
mov BP_SYM (main), d0 /* main. */
/* Call the user's main function, and exit with its value.
But let the libc call main. */
call BP_SYM (__libc_start_main),[],0
call BP_SYM (abort),[],0 /* Crash if somehow `exit' does return. */
/* Define a symbol for the first piece of initialized data. */
.data
.globl __data_start
__data_start:
.long 0
.weak data_start
data_start = __data_start
|
