mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-14 09:01:07 +00:00
121 lines
3.7 KiB
ArmAsm
121 lines
3.7 KiB
ArmAsm
/* Copyright (C) 1995-2023 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
|