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/* Machine-dependent ELF startup code. OpenRISC version.
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>
/* Initial entry point code for the dynamic linker.
The function _dl_start is the real entry point;
it's return value is the user program's entry point. */
ENTRY (_start)
/* Count arguments in r11 */
l.ori r3, r1, 0
l.movhi r11, 0
1:
l.addi r3, r3, 4
l.lwz r12, 0(r3)
l.sfnei r12, 0
l.addi r11, r11, 1
l.bf 1b
l.nop
l.addi r11, r11, -1
/* store argument counter to stack. */
l.sw 0(r1), r11
/* Load the PIC register. */
l.jal 0x8
l.movhi r16, gotpchi(_GLOBAL_OFFSET_TABLE_-4)
l.ori r16, r16, gotpclo(_GLOBAL_OFFSET_TABLE_+0)
l.add r16, r16, r9
l.ori r3, r1, 0
l.jal _dl_start
l.nop
/* Save user entry in a call saved reg. */
l.ori r22, r11, 0
/* Fall through to _dl_start_user. */
_dl_start_user:
/* Set up for _dl_init. */
/* Load _rtld_local (a.k.a _dl_loaded). */
l.lwz r12, got(_rtld_local)(r16)
l.lwz r3, 0(r12)
/* Load argc */
l.lwz r18, got(_dl_argc)(r16)
l.lwz r4, 0(r18)
/* Load argv */
l.lwz r20, got(_dl_argv)(r16)
l.lwz r5, 0(r20)
/* Load envp = &argv[argc + 1]. */
l.slli r6, r4, 2
l.addi r6, r6, 4
l.add r6, r6, r5
l.jal plt(_dl_init)
l.nop
/* Now set up for user entry.
The already defined ABI loads argc and argv from the stack.
argc = 0(r1)
argv = r1 + 4
*/
/* Load SP as argv - 4. */
l.lwz r3, 0(r20)
l.addi r1, r3, -4
/* Save argc. */
l.lwz r3, 0(r18)
l.sw 0(r1), r3
/* Pass _dl_fini function address to _start.
Next start.S will then pass this as rtld_fini to __libc_start_main. */
l.lwz r3, got(_dl_fini)(r16)
l.jr r22
l.nop
END (_start)
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