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/* Copyright (C) 1995-2024 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.
In addition to the permissions in the GNU Lesser General Public
License, the Free Software Foundation gives you unlimited
permission to link the compiled version of this file with other
programs, and to distribute those programs without any restriction
coming from the use of this file. (The GNU Lesser General Public
License restrictions do apply in other respects; for example, they
cover modification of the file, and distribution when not linked
into another program.)
Note that people who make modified versions of this file are not
obligated to grant this special exception for their modified
versions; it is their choice whether to do so. The GNU Lesser
General Public License gives permission to release a modified
version without this exception; this exception also makes it
possible to release a modified version which carries forward this
exception.
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, see
<https://www.gnu.org/licenses/>. */
#include <sysdep.h>
/* 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:
x0/w0 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
8(sp) argv[0]
...
(8*argc)(sp) NULL
(8*(argc+1))(sp) envp[0]
...
NULL
*/
.text
ENTRY(_start)
/* Create an initial frame with 0 LR and FP */
cfi_undefined (x30)
mov x29, #0
mov x30, #0
/* Setup rtld_fini in argument register */
mov x5, x0
/* Load argc and a pointer to argv */
ldr PTR_REG (1), [sp, #0]
add x2, sp, #PTR_SIZE
/* Setup stack limit in argument register */
mov x6, sp
#ifdef PIC
# ifdef SHARED
adrp x0, :got:main
ldr PTR_REG (0), [x0, #:got_lo12:main]
# else
adrp x0, __wrap_main
add x0, x0, :lo12:__wrap_main
# endif
#else
/* Set up the other arguments in registers */
MOVL (0, main)
#endif
mov x3, #0 /* Used to be init. */
mov x4, #0 /* Used to be fini. */
/* __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
#if defined PIC && !defined SHARED
/* When main is not defined in the executable but in a shared library
then a wrapper is needed in crt1.o of the static-pie enabled libc,
because crt1.o and rcrt1.o share code and the later must avoid the
use of GOT relocations before __libc_start_main is called. */
__wrap_main:
BTI_C
b main
#endif
END(_start)
/* 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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