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/* Startup code for ARM & ELF
Copyright (C) 1995, 1996, 1997, 1998, 2001, 2002 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 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., 51 Franklin Street, Fifth Floor, Boston,
MA 02110-1301, 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
.type _start,#function
_start:
/* Clear the frame pointer since this is the outermost frame. */
addi x8, x0, 0
ld a2, (sp)
addi sp, sp, 4
/* Pop argc off the stack and save a pointer to argv */
la x5, operatingsystem_parameter_argc
la x6,operatingsystem_parameter_argv
sd a2, (x5)
/* calc envp */
addi a4,a2,1
slli a4,a4,3
add a4,sp,a4
la x5, operatingsystem_parameter_envp
sd sp,(a3)
sd a4,(x5)
/* Save initial stackpointer */
la x5,__stkptr
sd sp, (x5)
/* Initialize gmon */
mov r2,#1
ldr r1,=_etext
ldr r0,=_start
bl __monstartup
ldr r0,=_mcleanup
bl atexit
/* argc already loaded to a2*/
ldr ip, =operatingsystem_parameter_argc
ldr a2,[ip]
/* Fetch address of fini */
ldr ip, =_fini
/* load argv */
mov a3, sp
/* Push stack limit */
str a3, [sp, #-4]!
/* Push rtld_fini */
str a1, [sp, #-4]!
/* Set up the other arguments in registers */
ldr a1, =PASCALMAIN
ldr a4, =_init
/* Push fini */
str ip, [sp, #-4]!
/* __libc_start_main (main, argc, argv, init, fini, rtld_fini, stack_end) */
/* Let the libc call main and exit with its return code. */
bl __libc_start_main
/* should never get here....*/
bl abort
.globl _haltproc
.type _haltproc,#function
_haltproc:
ldr r0,=operatingsystem_result
ldrb r0,[r0]
swi 0x900001
b _haltproc
.globl _haltproc_eabi
.type _haltproc_eabi,#function
_haltproc_eabi:
bl exit /* libc exit */
ldr r0,=operatingsystem_result
ldrb r0,[r0]
mov r7,#248
swi 0x0
b _haltproc_eabi
/* 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
.bss
.comm __stkptr,4
.comm operatingsystem_parameter_envp,4
.comm operatingsystem_parameter_argc,4
.comm operatingsystem_parameter_argv,4
.section ".comment"
.byte 0
.ascii "generated by FPC http://www.freepascal.org\0"
/* We need this stuff to make gdb behave itself, otherwise
gdb will chokes with SIGILL when trying to debug apps.
*/
.section ".note.ABI-tag", "a"
.align 4
.long 1f - 0f
.long 3f - 2f
.long 1
0: .asciz "GNU"
1: .align 4
2: .long 0
.long 2,0,0
3: .align 4
.section .note.GNU-stack,"",%progbits
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