mirror of
https://sourceware.org/git/glibc.git
synced 2024-11-23 13:30:06 +00:00
95 lines
2.5 KiB
ArmAsm
95 lines
2.5 KiB
ArmAsm
/* Copyright (C) 1995-2017 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, see
|
|
<http://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
|
|
.globl _start
|
|
.type _start,#function
|
|
_start:
|
|
/* Create an initial frame with 0 LR and FP */
|
|
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 SHARED
|
|
adrp x0, :got:main
|
|
ldr PTR_REG (0), [x0, #:got_lo12:main]
|
|
|
|
adrp x3, :got:__libc_csu_init
|
|
ldr PTR_REG (3), [x3, #:got_lo12:__libc_csu_init]
|
|
|
|
adrp x4, :got:__libc_csu_fini
|
|
ldr PTR_REG (4), [x4, #:got_lo12:__libc_csu_fini]
|
|
#else
|
|
/* Set up the other arguments in registers */
|
|
ldr PTR_REG (0), =main
|
|
ldr PTR_REG (3), =__libc_csu_init
|
|
ldr PTR_REG (4), =__libc_csu_fini
|
|
#endif
|
|
|
|
/* __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
|
|
|
|
/* 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
|