glibc/sysdeps/aarch64/dl-start.S

54 lines
1.6 KiB
ArmAsm

/* ld.so _start code.
Copyright (C) 2022-2024 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.
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>
ENTRY (_start)
/* Create an initial frame with 0 LR and FP */
cfi_undefined (x30)
mov x29, #0
mov x30, #0
mov x0, sp
PTR_ARG (0)
bl _dl_start
/* Returns user entry point in x0. */
mov PTR_REG (21), PTR_REG (0)
.globl _dl_start_user
.type _dl_start_user, %function
_dl_start_user:
/* Get argc. */
ldr PTR_REG (1), [sp]
/* Get argv. */
add x2, sp, PTR_SIZE
/* Compute envp. */
add PTR_REG (3), PTR_REG (2), PTR_REG (1), lsl PTR_LOG_SIZE
add PTR_REG (3), PTR_REG (3), PTR_SIZE
adrp x16, _rtld_local
add PTR_REG (16), PTR_REG (16), :lo12:_rtld_local
ldr PTR_REG (0), [x16]
bl _dl_init
/* Load the finalizer function. */
adrp x0, _dl_fini
add PTR_REG (0), PTR_REG (0), :lo12:_dl_fini
/* Jump to the user's entry point. */
mov x16, x21
br x16
END (_start)