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/*
* Copyright (C) 2004-2007 Atmel Corporation
*
* This file is subject to the terms and conditions of the GNU Lesser General
* Public License. See the file "COPYING.LIB" in the main directory of this
* archive for more details.
*
* When we enter _start, the stack looks like this:
* argc argument counter
* argv[0] pointer to program name
* argv[1..argc-1] pointers to program args
* NULL
* env[0..N] pointers to environment variables
* NULL
*
* r12 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.
*
* We're going to call the following function:
* __uClibc_main(int (*main)(int, char **, char **), int argc,
* char **argv, void (*app_init)(void), void (*app_fini)(void),
* void (*rtld_fini)(void), void *stack_end)
*
* So we need to set up things as follows:
* r12 = address of main
* r11 = argc
* r10 = &argv[0]
* r9 = address of _init
* r8 = address of _fini
* sp[0] = whatever we got passed in r12
*/
#include <features.h>
.text
.global _start
.type _start, @function
_start:
/* Clear the frame pointer and link register since this is the outermost frame. */
mov r7, 0
mov lr, 0
ld.w r11, sp++ /* argc */
mov r10, sp /* &argv[0] */
st.w --sp, r10 /* stack_end */
st.w --sp, r12 /* rtld_fini */
#ifdef __PIC__
lddpc r6, .L_GOT
.L_RGOT:
rsub r6, pc
lda.w r9, _init
lda.w r8, _fini
lda.w r12, main
/* Ok, now run uClibc's main() -- should not return */
call __uClibc_main
.align 2
.L_GOT:
.long .L_RGOT - _GLOBAL_OFFSET_TABLE_
#else
lddpc r9, __init_addr /* app_init */
lddpc r8, __fini_addr /* app_fini */
lddpc r12, __main_addr /* main */
/* Ok, now run uClibc's main() -- should not return */
lddpc pc, ___uClibc_main_addr
.align 2
__init_addr:
.long _init
__fini_addr:
.long _fini
__main_addr:
.long main
___uClibc_main_addr:
.long __uClibc_main
#endif
.size _start, . - _start
/*
* The LSB says we need this.
*/
.section ".note.ABI-tag", "a"
.align 4
.long 2f - 1f /* namesz */
.long 4f - 3f /* descsz */
.long 1 /* type */
1: .asciz "GNU" /* name */
2: .align 4
3: .long 0 /* Linux executable */
.long 2,6,0 /* Earliest compatible kernel */
4: .align 4
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