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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:
.option push
.option norelax
1:auipc gp, %pcrel_hi(__global_pointer$)
addi gp, gp, %pcrel_lo(1b)
.option pop
/* Clear the frame pointer since this is the outermost frame. */
addi x8, x0, 0
ld a2, 0(sp)
addi sp, sp, 8
/* Pop argc off the stack and save a pointer to argv */
1:auipc x8,%pcrel_hi(operatingsystem_parameter_argc)
sd a2,%pcrel_lo(1b)(x8)
1:auipc x8,%pcrel_hi(operatingsystem_parameter_argv)
sd sp,%pcrel_lo(1b)(x8)
addi a4, a2, 1
slli a4, a4, 3
add a4, sp, a4
1:auipc x8,%pcrel_hi(operatingsystem_parameter_envp)
sd a4,%pcrel_lo(1b)(x8)
/* Save initial stackpointer */
1:auipc x8,%pcrel_hi(__stkptr)
sd sp,%pcrel_lo(1b)(x8)
/* Fetch address of fini */
1:auipc x8,%pcrel_hi(_fini)
addi a2,x8,%pcrel_lo(1b)
/* argc already loaded to a2*/
/* load argv */
addi a3, sp, 0
/* Push stack limit */
sd a3, -8(sp)
addi sp, sp, -8
/* Push rtld_fini */
sd a1, -8(sp)
addi sp, sp, -8
/* Set up the other arguments in registers */
1:auipc x8,%pcrel_hi(PASCALMAIN)
addi a1, x8, %pcrel_lo(1b)
1:auipc x8,%pcrel_hi(_init)
addi a4, x8, %pcrel_lo(1b)
/* Push fini */
sd a2, -8(sp)
addi sp, sp, -8
/* __libc_start_main (main, argc, argv, init, fini, rtld_fini, stack_end) */
/* Let the libc call main and exit with its return code. */
1:auipc x8,%pcrel_hi(__libc_start_main)
jalr ra, x8, %pcrel_lo(1b)
/* should never get here....*/
1:auipc x8,%pcrel_hi(abort)
jalr ra, x8, %pcrel_lo(1b)
.globl _haltproc
.type _haltproc,function
_haltproc:
1:auipc x8,%pcrel_hi(operatingsystem_result)
lbu x1,%pcrel_lo(1b)(x8)
addi x17, x0, 94
ecall
jal x0, _haltproc
/* 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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