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/* Startup code for SH & ELF.
Copyright (C) 1999-2021 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/>. */
/* 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:
r4 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
4(sp) argv[0]
...
(4*argc)(sp) NULL
(4*(argc+1))(sp) envp[0]
...
NULL
*/
.text
.globl _start
.type _start,@function
_start:
/* Clear the frame pointer since this is the outermost frame. */
mov #0, r14
/* Pop argc off the stack and save a pointer to argv */
mov.l @r15+,r5
mov r15, r6
/* Push the last arguments to main() onto the stack */
mov.l r4,@-r15
mov.l L_fini,r0
mov.l r0,@-r15
/* Set up the other arguments for main() that go in registers */
mov.l L_main,r4
mov.l L_init,r7
/* __libc_start_main (main, argc, argv, init, fini, rtld_fini) */
/* Let the libc call main and exit with its return code. */
mov.l L_libc_start_main,r1
jsr @r1
nop
/* should never get here....*/
mov.l L_abort,r1
jsr @r1
nop
.align 2
L_main:
.long main
L_init:
.long __libc_csu_init
L_fini:
.long __libc_csu_fini
L_libc_start_main:
.long __libc_start_main
L_abort:
.long 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
.global __fpscr_values
__fpscr_values:
.long 0
.long 0x80000
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