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/* Startup code compliant to the ELF CRIS ABI (to-be-written).
Copyright (C) 2001, 2002 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, 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 __libc_csu_init:PLTG,r13
add.d r0,r13
move.d __libc_csu_fini:PLTG,r9
add.d r0,r9
move.d main:PLTG,r10
add.d r0,r10
#else
move.d __libc_csu_init,r13
move.d __libc_csu_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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