glibc/sysdeps/sparc/sparc64/start.S

101 lines
3.5 KiB
ArmAsm

/* Startup code for elf64-sparc
Copyright (C) 1997-2020 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Richard Henderson <richard@gnu.ai.mit.edu>, 1997.
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>
.section ".text"
.align 4
.global _start
.type _start,#function
_start:
#ifdef PIC
SETUP_PIC_REG(l7)
#endif
/* Terminate the stack frame, and reserve space for functions to
drop their arguments. */
mov %g0, %fp
sub %sp, 6*8, %sp
/* Extract the arguments and environment as encoded on the stack. The
argument info starts after one register window (16 words) past the SP,
plus the bias we added, plus the magic v9 STACK_BIAS. */
ldx [%sp+STACK_BIAS+22*8], %o1
add %sp, STACK_BIAS+23*8, %o2
/* Load the addresses of the user entry points. */
#ifndef PIC
sethi %hi(main), %o0
sethi %hi(__libc_csu_init), %o3
sethi %hi(__libc_csu_fini), %o4
or %o0, %lo(main), %o0
or %o3, %lo(__libc_csu_init), %o3
or %o4, %lo(__libc_csu_fini), %o4
#else
sethi %gdop_hix22(main), %o0
sethi %gdop_hix22(__libc_csu_init), %o3
sethi %gdop_hix22(__libc_csu_fini), %o4
xor %o0, %gdop_lox10(main), %o0
xor %o3, %gdop_lox10(__libc_csu_init), %o3
xor %o4, %gdop_lox10(__libc_csu_fini), %o4
ldx [%l7 + %o0], %o0, %gdop(main)
ldx [%l7 + %o3], %o3, %gdop(__libc_csu_init)
ldx [%l7 + %o4], %o4, %gdop(__libc_csu_fini)
#endif
/* When starting a binary via the dynamic linker, %g1 contains the
address of the shared library termination function, which will be
registered with atexit(). If we are statically linked, this will
be NULL. */
mov %g1, %o5
/* Let libc do the rest of the initialization, and call main. */
call __libc_start_main
nop
/* Die very horribly if exit returns. */
illtrap 0
.size _start, .-_start
/* Define a symbol for the first piece of initialized data. */
.data
.globl __data_start
__data_start:
.long 0
weak_alias (__data_start, data_start)