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/* Startup code for ARM & ELF
Copyright (C) 1995, 1996, 1997, 1998 Free Software Foundation, Inc.
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 Library General Public License as
published by the Free Software Foundation; either version 2 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
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. 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.
Note that the code in the .init section has already been run.
This includes _init and _libc_init
At this entry point, most registers' values are unspecified, except:
a1 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:
0(sp) argc
4(sp) argv[0]
...
(4*argc)(sp) NULL
(4*(argc+1))(sp) envp[0]
...
NULL
*/
.text
.globl _start
_start:
/* Clear the frame pointer since this is the outermost frame. */
mov fp, #0
/* Pop argc off the stack and save a pointer to argv */
ldmfd sp!, {a2}
mov a3, sp
/* Push the last arguments to main() onto the stack */
stmfd sp!, {a1}
ldr a1, =_fini
stmfd sp!, {a1}
/* Set up the other arguments for main() that go in registers */
ldr a1, =main
ldr a4, =_init
/* __libc_start_main (main, argc, argv, init, fini, rtld_fini) */
/* Let the libc call main and exit with its return code. */
bl __libc_start_main
/* should never get here....*/
bl abort
/* 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
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