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/* Startup code compliant to the ELF CRIS ABI (to-be-written).
Copyright (C) 2001 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 Library General Public License as
published by the Free Software Foundation; either version 2 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
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If not,
write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#include <sysdep.h>
/* This is the canonical entry point, usually the first thing in the text
segment. When the entry point runs, most registers' values are
unspecified, except for:
R10 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:
[SP] argc
[SP+4] argv[0]
...
[SP+4*argc] NULL
[SP+4*(argc+1)] envp[0]
...
NULL
*/
.syntax no_register_prefix
.text
.globl _start
.type _start,@function
_start:
/* Clear the frame pointer, to mark the outermost frame. */
moveq 0,r8
/* Move the shared library termination function to the right place
for __libc_main. */
move.d r10,r9
/* Extract the arguments as encoded on the stack and set up the
arguments for `main': argc, argv. envp will be determined
later in __libc_start_main. */
/* Get the argument count. */
move.d [sp],r11
/* Store the stack pointer as end of stack. We overwrite
the incoming argc. */
move.d sp,[sp]
/* The argument vector starts just after the argument count. */
move.d sp,r12
addq 4,r12
/* There are seven arguments to __libc_start_main:
r10: main - Address of it.
r11: argc
r12: argv
r13: init - Function to call.
[sp]: fini - Function to register with atexit.
[sp+4]: rtld_fini - Another function to register with atexit.
[sp+8]: stack_end - Top of stack (actually same as argv).
The last two are passed on stack. */
/* Store the fini function coming from the dynamic loader. */
push r9
/* Get the addresses of our own entry points to `.fini' and
`.init'. */
#ifdef __PIC__
/* If for some reason this program is compiled as PIC, set up R0. */
move.d pc,r0
sub.d .:GOTOFF,r0
move.d _init:PLTG,r13
add.d r0,r13
move.d _fini:PLTG,r9
add.d r0,r9
move.d main:PLTG,r10
add.d r0,r10
#else
move.d _init,r13
move.d _fini,r9
move.d main,r10
#endif
push r9
/* Call the user's main function, and exit with its value. But
let the libc call main. */
PLTCALL (__libc_start_main)
/* Crash if somehow `exit' does return. We have at least 8192
invalid addresses to choose from. */
test.d [6502]
/* Stop the unstoppable. */
0:
ba 0b
nop
/* 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
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